Designing timber highway bridge superstructures using AASHTO?LRFD specifications

Treesearch

James P. Wacker; James S. Groenier

2007-01-01

The allowable-stress design methodology that has been used for decades to design timber bridge superstructures is being replaced in the near future. Beginning in October 2007, bridge designers will be required by the Federal Highway Administration (FHWA) to utilize the Load and Resistance Factor Design (LRFD) design specifications published by the American Association...

Project 2d: Calibration of Load and Resistance Factors in LRFD Foundation Design Specifications

DOT National Transportation Integrated Search

2011-02-01

This report summarizes the findings and recommendations on the impact of foundation settlements on the reliability of bridge superstructures. As a : collaborative effort of an overall initiative for the development of LRFD foundation design specifica...

Development of LRFD procedures for bridge pile foundations in Iowa - volume III : recommended resistance factors with consideration of construction control and setup.

DOT National Transportation Integrated Search

2012-02-01

The Federal Highway Administration (FHWA) mandated utilizing the Load and Resistance Factor Design (LRFD) approach for all new bridges initiated in the United States after October 1, 2007. As a result, there has been a progressive move among state De...

Recalibration of the GRLWEAP LRFD resistance factor for Oregon DOT.

DOT National Transportation Integrated Search

2011-02-01

The Bridge Section of the Oregon Department of Transportation (ODOT) is responsible for the design of all bridge structures and routinely uses GRLWEAP for controlling pile driving stresses and establishing capacity from the bearing graph. The LRFD re...

Comparative analysis of design codes for timber bridges in Canada, the United States, and Europe

Treesearch

James Wacker; James (Scott) Groenier

2010-01-01

The United States recently completed its transition from the allowable stress design code to the load and resistance factor design (LRFD) reliability-based code for the design of most highway bridges. For an international perspective on the LRFD-based bridge codes, a comparative analysis is presented: a study addressed national codes of the United States, Canada, and...

Correlation of shear design between AASHTO LRFD bridge design specifications and AASHTO Guide Specifications for the LRFD Seismic Bridge Design.

DOT National Transportation Integrated Search

2017-01-05

This report presents the analytical study of the shear capacity of reinforced concrete columns using both the AASHTO LRFD Bridge Design Specifications and the AASHTO Guide Specifications for the LRFD Seismic Bridge Design. The study investigates vari...

Development of LRFD design procedures for bridge piles in Iowa : field testing of steel H-piles in clay, sand, and mixed soils and data analysis (volume II).

DOT National Transportation Integrated Search

2011-09-01

In response to the mandate on Load and Resistance Factor Design (LRFD) implementations by the Federal Highway Administration : (FHWA) on all new bridge projects initiated after October 1, 2007, the Iowa Highway Research Board (IHRB) sponsored these r...

Resistance factors for 100% dynamic testing, with and without static load tests.

DOT National Transportation Integrated Search

2011-05-01

Current department of transportation (DOT) and Federal Highway Administration (FHWA) practice has highly : variable load and resistance factor design (LRFD) resistance factors, , for driven piles from design (e.g., Standard : Penetration Tests (SPT...

Development of recommended resistance factors for drilled shafts in weak rocks based on o-cell tests.

DOT National Transportation Integrated Search

2010-03-01

From October 1, 2007, the new bridges on federal-aid funded projects are mandated to be designed to meet : American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design : (LRFD) Bridge Design Specificat...

Calibration of resistance factors for drilled shafts for the new FHWA design method.

DOT National Transportation Integrated Search

2013-01-01

The Load and Resistance Factor Design (LRFD) calibration of deep foundation in Louisiana was first completed for driven piles (LTRC Final Report 449) in May 2009 and then for drilled shafts using 1999 FHWA design method (ONeill and Reese method) (...

Development of recommended resistance factors for drilled shafts in weak rocks based on o-cell tests : [technical summary].

DOT National Transportation Integrated Search

2010-03-01

Since October 1st 2007, federal-funded projects including new bridges have been mandated to be designed to meet American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design (LRFD) Bridge Design Specifi...

Resistance factors for 100% dynamic testing, with and without static load tests : [summary].

DOT National Transportation Integrated Search

2011-01-01

The Federal Highway Administration (FHWA) and : most state departments of transportation have : adopted the Load and Resistance Factor (LRFD) : approach to design. Critical to the design of : piles in this approach is the development of a : resistanc...

Update of bridge design standards in Alabama for AASHTO LRFD seismic design requirements.

DOT National Transportation Integrated Search

2013-11-01

The Alabama Department of Transportation (ALDOT) has been required to update their bridge design to the LRFD Bridge Design Specifications. This transition has resulted in changes to the seismic design standards of bridges in the state. Multiple bridg...

Calibration of Resistance Factors Needed in the LRFD Design of Driven Piles : LTRC technical summary report 449.

DOT National Transportation Integrated Search

2009-05-01

The allowable stress design (ASD) method had been used for many years in the design of bridges, which involves : applying a factor of safety (FS) to account for uncertainties in applied loads and soil resistance. The magnitude of : FS depends on the ...

Development of preliminary load and resistance factor design of drilled shafts in Iowa.

DOT National Transportation Integrated Search

2014-10-01

The Federal Highway Administration (FHWA) mandated utilizing the Load and Resistance Factor Design (LRFD) approach for all new : bridges initiated in the United States after October 1, 2007. To achieve part of this goal, a database for Drilled SHAft ...

Influence of the new LRFD seismic guidelines on the design of bridges in Virginia.

DOT National Transportation Integrated Search

2004-01-01

The Virginia Department of Transportation is currently using the AASHTO Standard Specifications for Highway Bridges, with some modifications, for its seismic highway bridge design. In April 2001, the Recommended LRFD Guidelines for the Seismic Design...

Evaluation of finger plate and flat plate connection design.

DOT National Transportation Integrated Search

2016-01-01

This project investigates the cause(s) of premature deterioration of MoDOT finger plate and flat plate expansion devices : under high traffic volumes and then uses that information to design new Load and Resistance Factor Design (LRFD) : finger plate...

LRFD software for design and actual ultimate capacity of confined rectangular columns : [technical summary].

DOT National Transportation Integrated Search

2013-04-01

Columns are considered the most critical elements in structures. The unconfined analysis for columns is well established in the literature. Structural design codes dictate reduction factors for safety. It wasnt until very recently that design spec...

Condition factor calibration for load and resistance factor rating of steel girder bridges : final report.

DOT National Transportation Integrated Search

2016-06-01

Load and Resistance Factor Rating (LRFR) is a reliability-based rating procedure complementary to Load and Resistance Factor Design (LRFD). The intent of LRFR is to provide consistent reliability for all bridges regardless of in-situ condition. The p...

Serviceability-related issues for bridge live load deflection and construction closure pours : [research summary].

DOT National Transportation Integrated Search

2015-06-01

The Load and Resistance Factor Design (LRFD) method has evolved to become a : more reliable approach to bridge design in the past century. Nevertheless, safety is : always the number one concern in the design of bridge structures. Equally important, ...

Embedded data collector (EDC) phase II load and resistance factor design (LRFD) : [summary].

DOT National Transportation Integrated Search

2015-07-01

Piles that support bridge structures are designed for the specific site characteristics and loads : that the piles are expected to bear. In Florida, driven piles are monitored during installation : (dynamically tested) to assess resistance, com...

Load and resistance factor design of drilled shafts in shale for lateral loading.

DOT National Transportation Integrated Search

2014-04-01

A research project involving 32 drilled shaft load tests was undertaken to establish LRFD procedures for : design of drilled shafts subjected to lateral loads. Tests were performed at two Missouri Department of : Transportation (MoDOT) geotechnical r...

Designing timber bridge superstructures : a comparison of U.S. and Canadian bridge codes.

Treesearch

James Scott Groenier; James P. Wacker

2008-01-01

Several changes relating to timber bridges have been incorporated into the AASHTO-LRFD Bridge Design Specifications recently. In addition, the Federal Highway Administration is strongly encouraging an LRFD-based design approach for all new bridges in the United States. The Bridge Design Code in Canada was one of the first to adopt the limit states design philosophy,...

LRFD Resistance Factor Calibration for Axially Loaded Drilled Shafts in the Las Vegas Valley

DOT National Transportation Integrated Search

2016-07-19

Resistance factors for LRFD of axially loaded drilled shafts in the Las Vegas Valley are calibrated using data from 41 field load tests. In addition to the traditional implementation of Monte Carlo (MC) simulations for calibration, a more robust tech...

Analysis of large truck collisions with bridge piers : phase 1, report of guidelines for designing bridge piers and abutments for vehicle collisions.

DOT National Transportation Integrated Search

2010-05-01

The American Association of State Highway and Transportation Officials (AASHTO) Load and : Resistance Factor Design (LRFD) Bridge Design Specifications require that abutments and piers located : within a distance of 30.0 ft of the edge of the road...

Synthesis and evaluation of lightweight concrete research relevant to the AASHTO LRFD bridge design specifications : potential revisions for definition and mechanical properties.

DOT National Transportation Integrated Search

2012-11-01

Much of the fundamental basis for the current lightweight concrete provisions in the AASHTO LRFD Bridge : Design Specifications is based on research of lightweight concrete (LWC) from the 1960s. The LWC that was : part of this research used tradition...

Price trends for federal-aid highway construction : 1987 base, second quarter 1997

DOT National Transportation Integrated Search

1999-03-01

This summary report highlights the March 1998 Federal Highway Administration (FHWA) scanning team organized to review and document developments in load and resistance factor design (LRFD) methods and alternative contracting practices related to geote...

Modification of LRFD resistance factors based on site variability : final report, November 2009.

DOT National Transportation Integrated Search

2009-11-01

Current practice by the Florida Department of Transportation (FDOT), Federal Highway Administration (FHWA), and American Association of State Highway Transportation Officials (AASHTO) for deep foundation design is to use a constant load and resistanc...

Calibration of region-specific gates equation for LRFD.

DOT National Transportation Integrated Search

2014-02-01

The objectives of this research are to recalibrate the FHWA-modi ed Gates equation : and update the associated LRFD resistance factor for pile types and local soil conditions : encountered in Louisiana. This research is consistent with FHWA recomm...

Synthesis and evaluation of lightweight concrete research relevant to the AASHTO LRFD bridge design specifications : identification of articles for further evaluation and potential revision.

DOT National Transportation Integrated Search

2012-11-01

Much of the fundamental basis for the current lightweight concrete provisions in the AASHTO LRFD Bridge : Design Specifications is based on research of lightweight concrete (LWC) from the 1960s. The LWC that was : part of this research used tradition...

Software for AASHTO LRFD combined shear and torsion computations using modified compression field theory and 3D truss analogy.

DOT National Transportation Integrated Search

2011-10-01

The shear provisions of the AASHTO LRFD Bridge Design Specifications (2008), as well as the simplified : AASHTO procedure for prestressed and non-prestressed reinforced concrete members were investigated and compared : to their equivalent ACI 318-08 ...

Assessment of current AASHTO LRFD methods for static pile capacity analysis in Rhode Island soils.

DOT National Transportation Integrated Search

2013-07-01

This report presents an assessment of current AASHTO LRFD methods for static pile capacity analysis in Rhode : Island soils. Current static capacity methods and associated resistance factors are based on pile load test data in sands : and clays. Some...

Geotechnical LFRD calculations of settlement and bearing capacity of GDOT shallow bridge foundations and retaining walls.

DOT National Transportation Integrated Search

2016-08-09

The AASHTO codes for Load Resistance Factored Design (LRFD) regarding shallow bridge foundations : and walls have been implemented into a set of spreadsheet algorithms to facilitate the calculations of bearing : capacity and footing settlements on na...

Embedded data collector (EDC) phase II load and resistance factor design (LRFD).

DOT National Transportation Integrated Search

2015-09-01

A total of 16 static load test results was collected in Florida and Louisiana. New static load tests on five test piles : in Florida (four of which were voided) were monitored with Embedded Data Collector (EDC) instrumentation and : contributed to th...

Software for AASHTO LRFD combined shear and torsion computations using modified compression field theory and 3D truss analogy : technical summary.

DOT National Transportation Integrated Search

2011-10-01

The shear provisions of the AASHTO LRFD Bridge Design Specifications (2008), as well as the simplified AASHTO procedure for prestressed and non-prestressed reinforced concrete members were investigated and compared to their equivalent ACI 318-08 prov...

Moving Aerospace Structural Design Practice to a Load and Resistance Factor Approach

NASA Technical Reports Server (NTRS)

Larsen, Curtis E.; Raju, Ivatury S.

2016-01-01

Aerospace structures are traditionally designed using the factor of safety (FOS) approach. The limit load on the structure is determined and the structure is then designed for FOS times the limit load - the ultimate load. Probabilistic approaches utilize distributions for loads and strengths. Failures are predicted to occur in the region of intersection of the two distributions. The load and resistance factor design (LRFD) approach judiciously combines these two approaches by intensive calibration studies on loads and strength to result in structures that are efficient and reliable. This paper discusses these three approaches.

Refinement of Strut-and-Tie Model for Reinforced Concrete Deep Beams

PubMed Central

Panjehpour, Mohammad; Chai, Hwa Kian; Voo, Yen Lei

2015-01-01

Deep beams are commonly used in tall buildings, offshore structures, and foundations. According to many codes and standards, strut-and-tie model (STM) is recommended as a rational approach for deep beam analyses. This research focuses on the STM recommended by ACI 318-11 and AASHTO LRFD and uses experimental results to modify the strut effectiveness factor in STM for reinforced concrete (RC) deep beams. This study aims to refine STM through the strut effectiveness factor and increase result accuracy. Six RC deep beams with different shear span to effective-depth ratios (a/d) of 0.75, 1.00, 1.25, 1.50, 1.75, and 2.00 were experimentally tested under a four-point bending set-up. The ultimate shear strength of deep beams obtained from non-linear finite element modeling and STM recommended by ACI 318-11 as well as AASHTO LRFD (2012) were compared with the experimental results. An empirical equation was proposed to modify the principal tensile strain value in the bottle-shaped strut of deep beams. The equation of the strut effectiveness factor from AASHTTO LRFD was then modified through the aforementioned empirical equation. An investigation on the failure mode and crack propagation in RC deep beams subjected to load was also conducted. PMID:26110268

Appendix G : end region design models.

DOT National Transportation Integrated Search

2013-03-01

The 2007 AASHTO LRFD Bridge Design Specifications contain prescriptive : requirements for the quantity and placement of confinement reinforcement located in the bottom : flange of pretensioned concrete I-girders. This chapter proposes a rational mode...

Structural design parameters of current WSDOT mixtures.

DOT National Transportation Integrated Search

2013-06-01

The AASHTO LRFD, as well as other design manuals, has specifications that estimate the structural performance of a concrete mixture with regard to compressive strength, tensile strength, and deformation-related properties such as the modulus of elast...

UDOT calibration of AASHTO's new prestress loss design equations.

DOT National Transportation Integrated Search

2009-07-01

In the next edition of the AASHTO LRFD Bridge Design Specifications the procedure to calculate prestress losses will change dramatically. The new equations are empirically based on high performance concrete from four states (Nebraska, New Hampshire, ...

UDOT's calibration of AASHTO's new prestress loss design equations.

DOT National Transportation Integrated Search

2009-07-01

In the next edition of the AASHTO LRFD Bridge Design Specifications the procedure to calculate prestress losses will change dramatically. The new equations are empirically based on high performance concrete from four states (Nebraska, New Hampshire, ...

Development of multimedia resource and short courses for LRFD design.

DOT National Transportation Integrated Search

2011-03-01

Multimedia technology is an essential instrument in the development of graduate engineers. This : multimedia package provides an exclusive background and an in-depth understanding of the new : technological advances in the design of concrete, steel a...

Appendix B : small beam tests.

DOT National Transportation Integrated Search

2013-03-01

The AASHTO LRFD Bridge Design Specifications (2007) require that confinement : reinforcement be placed around prestressing strands in the bottom bulb of pretensioned concrete : beams. Although the AASHTO specifications contain prescriptive requiremen...

Seismic Design Considerations : Volume I, Technical Approaches and Results; Volume II, Appendices II-VIII

DOT National Transportation Integrated Search

2012-03-01

NJDOT has adopted AASHTO Guide Specifications for LRFD Seismic Bridge Design approved by the Highway : Subcommittee on Bridges and Structures in 2007. The main objective of research presented in this report has : been to resolve following issue...

Design of mechanically stabilized earth wall connections and end of walls subjected to seismic loads.

DOT National Transportation Integrated Search

2014-01-01

The 4th Edition of the AASHTO LRFD Bridge Design Specifications requires all states to design for a 1,000- : year return period earthquake, as opposed to earlier editions 500-year return period. In response to this : requirement, the Colorado Depa...

High skew link slab bridge system with deck sliding over backwall or backwall sliding over abutments : appendices.

DOT National Transportation Integrated Search

2011-09-01

AASHTO LRFD (2010) requires combined live and thermal load effects for the service : limit state design. The Design Procedure described in the appendix will follow the : rationale developed by Ulku et al. (2009). Link slab design moments are calculat...

Statistical analysis of weigh-in-motion data for bridge design in Vermont.

DOT National Transportation Integrated Search

2014-10-01

This study investigates the suitability of the HL-93 live load model recommended by AASHTO LRFD Specifications : for its use in the analysis and design of bridges in Vermont. The method of approach consists in performing a : statistical analysis of w...

Association of Patient-Reported Readiness for Discharge and Hospital Consumer Assessment of Health Care Providers and Systems Patient Satisfaction Scores: A Retrospective Analysis.

PubMed

Schmocker, Ryan K; Holden, Sara E; Vang, Xia; Leverson, Glen E; Cherney Stafford, Linda M; Winslow, Emily R

2015-12-01

Patient-reported outcomes (PRO) have been increasingly emphasized, however, determining clinically valuable PRO has been problematic and investigation limited. This study examines the association of readiness for discharge, which has been described previously, with patient satisfaction and readmission. Data from adult patients admitted to our institution from 2009 to 2012 who completed both the Hospital Consumer Assessment of Healthcare Providers and Systems and the Press Ganey surveys post discharge were extracted from an existing database of patients (composed of 220 patients admitted for small bowel obstruction and 98 patients with hospital stays ≥ 21 days). Using the survey question, "Did you feel ready for discharge?" (RFD), 2 groups were constructed, those RFD and those with lesser degrees of readiness (ie, less ready for discharge [LRFD]) using topbox methodology. Outcomes, readmission rates, and satisfaction were compared between RFD and LRFD groups. Three hundred and eighteen patients met the inclusion criteria; 45% were female and 94% were Caucasian. Median age was 62.3 years (interquartile range 52.5 to 70.8 year). Median length of stay was 10 days (interquartile range 6.0 to 24.0 days) and 69.2% were admitted with small bowel obstruction. The 30-day readmission rate was 14.3% and 55% indicated they were RFD. Those RFD and LRFD had similar demographics, comorbidity scores, and rates of surgery. Those RFD had higher overall hospital satisfaction (87.3% RFD vs 62.4% LRFD; p < 0.001), higher physician communication scores (median 3.0 RFD vs 2.0 LRFD; p < 0.001), and higher nursing communication scores (median 3.0 RFD vs 2.0 LRFD, p < 0.001). Readmission rates were similar between the groups (11.4% RFD vs 18.2% LRFD; p = 0.09). Readiness for discharge appears to be a clinically useful patient-reported metric, as those RFD have higher satisfaction with the hospital and physicians. Prospective investigation into variables affecting patient satisfaction in those LRFD is needed. Copyright © 2015 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Development of LRFD procedures for bridge pile foundations in Iowa - volume I : an electronic database for PIle LOad Tests (PILOT).

DOT National Transportation Integrated Search

2011-01-01

For well over 100 years, the Working Stress Design (WSD) approach has been the traditional basis for geotechnical design with regard to settlements or failure conditions. However, considerable effort has been put forth over the past couple of decades...

Rock mass classification system : transition from RMR to GSI.

DOT National Transportation Integrated Search

2013-11-01

The AASHTO LRFD Bridge Design Specifications is expected to replace the rock mass rating : (RMR) system with the Geological Strength Index (GSI) system for classifying and estimating : engineering properties of rock masses. This transition is motivat...

LRFD software for design and actual ultimate capacity of confined rectangular columns.

DOT National Transportation Integrated Search

2013-04-01

The analysis of concrete columns using unconfined concrete models is a well established practice. On the : other hand, prediction of the actual ultimate capacity of confined concrete columns requires specialized nonlinear : analysis. Modern codes and...

Comprehensive evaluation of fracture critical bridges.

DOT National Transportation Integrated Search

2014-02-01

Two-girder steel bridges are classified as fracture critical bridges based on the definition given in the AASHTO LRFD Bridge Design Specifications. In a fracture critical bridge a failure of a tension member leads to collapse of the bridge. However, ...

Upgrade of axially loaded pile-soil modeling with the implementation of LRFD design procedure.

DOT National Transportation Integrated Search

2012-02-01

This report and the accompanying computer code (Software, WBUZPILE) describe the : characterization and analysis of piles under axial loads. A combination of different formulas : obtained from ALDOT long time experience along with fundamental equatio...

Evaluation of long-term prestress losses in post-tensioned box-girder bridges.

DOT National Transportation Integrated Search

2011-03-01

Most of the recent highway bridges built in California have post-tensioned, cast-in-place, concrete box-girder superstructures rigidly connected to bridge columns. However, methods provided in the current (2007 and 2010) AASHTO LRFD Bridge Design Spe...

Safety Identifying of Integral Abutment Bridges under Seismic and Thermal Loads

PubMed Central

Easazadeh Far, Narges; Barghian, Majid

2014-01-01

Integral abutment bridges (IABs) have many advantages over conventional bridges in terms of strength and maintenance cost. Due to the integrity of these structures uniform thermal and seismic loads are known important ones on the structure performance. Although all bridge design codes consider temperature and earthquake loads separately in their load combinations for conventional bridges, the thermal load is an “always on” load and, during the occurrence of an earthquake, these two important loads act on bridge simultaneously. Evaluating the safety level of IABs under combination of these loads becomes important. In this paper, the safety of IABs—designed by AASHTO LRFD bridge design code—under combination of thermal and seismic loads is studied. To fulfill this aim, first the target reliability indexes under seismic load have been calculated. Then, these analyses for the same bridge under combination of thermal and seismic loads have been repeated and the obtained reliability indexes are compared with target indexes. It is shown that, for an IAB designed by AASHTO LRFD, the indexes have been reduced under combined effects. So, the target level of safety during its design life is not provided and the code's load combination should be changed. PMID:25405232

Managing Florida's fracture critical bridges - phases 1 and 2 : final report.

DOT National Transportation Integrated Search

2016-05-01

Based on the definition given in the AASHTO LRFD Bridge Design Specifications, twin steel box-girder bridges are : classified as bridges with fracture critical members (FCMs), in which a failure of a tension member is expected to : lead to a collapse...

High Strength Reinforcing Steel Bars : Concrete Shear Friction Interface : final report : Part A.

DOT National Transportation Integrated Search

2017-03-01

High-strength steel (HSS) reinforcement, specifically ASTM A706 Grade 80 (550), is now permitted by the AASHTO LRFD Bridge Design Specifications for use in reinforced concrete bridge components in non-seismic regions. Using Grade 80 (550) steel reinf...

High strength reinforcing steel bars : concrete shear friction interface : final report : Part A.

DOT National Transportation Integrated Search

2017-03-01

High-strength steel (HSS) reinforcement, specifically ASTM A706 Grade 80 (550), is now permitted by the AASHTO LRFD Bridge Design Specifications for use in reinforced concrete bridge components in non-seismic regions. Using Grade 80 (550) steel reinf...

High strength reinforcing steel bars : low cycle fatigue behavior : final report - part B.

DOT National Transportation Integrated Search

2017-03-01

High-strength steel (HSS) reinforcing steel, specifically ASTM A706 Grade 80 (550), is now permitted by the AASHTO LRFD Bridge Design Specifications for use in reinforced concrete bridge components in non-seismic regions. Using Grade 80 (550) reinfor...

High strength reinforcing steel bars : low-cycle fatigue behavior : final report - part B.

DOT National Transportation Integrated Search

2017-03-01

High-strength steel (HSS) reinforcing steel, specifically ASTM A706 Grade 80 (550), is now permitted by the AASHTO LRFD Bridge Design Specifications for use in reinforced concrete bridge components in non-seismic regions. Using Grade 80 (550) reinfor...

Effects of increasing the allowable compressive stress at release on the shear strength of prestressed concrete girders.

DOT National Transportation Integrated Search

2008-09-01

In recent years, several research projects have been conducted to study the feasibility of increasing the allowable : compressive stress in concrete at prestress transfer, currently defined as 0.60f'ci in the AASHTO LRFD Bridge : Design Specification...

Investigation of pile setup (freeze) in Alabama : development of a setup prediction method and implementation into LRFD driven pile design.

DOT National Transportation Integrated Search

2015-06-01

The Alabama Department of Transportation (ALDOT) often uses deep foundations : consisting of driven piles, particularly in the southern half of the state, to support bridges or other : highway structures. In the fiscal year 2012, a total of 22 bridge...

Dynamic Load on Continuous Multi-Lane Bridge Deck from Moving Vehicles

NASA Astrophysics Data System (ADS)

ZHU, X. Q.; LAW, S. S.

2002-04-01

The dynamic loading on a multi-lane continuous bridge deck due to vehicles moving on top at a constant velocity is investigated. The bridge is modelled as a multi-span continuous orthotropic rectangular plate with line rigid intermediate supports. The vehicle is simulated as a two-axle three-dimensional vehicle model with seven degrees of freedom according to the H20-44 vehicle design loading (AASHTO LRFD Bridge Design Specifications 1998 American Association of State Highway and Transportation Officials [1]). The dynamic behavior of the bridge deck under single and several vehicles moving in different lanes is analyzed using the orthotropic plate theory and modal superposition technique. The dynamic loading is studied in terms of the dynamic impact factor of the bridge deck. The impact factor is found varying in an opposite trend as the dynamic responses for the different loading cases under study.

Design optimization of steel frames using an enhanced firefly algorithm

NASA Astrophysics Data System (ADS)

Carbas, Serdar

2016-12-01

Mathematical modelling of real-world-sized steel frames under the Load and Resistance Factor Design-American Institute of Steel Construction (LRFD-AISC) steel design code provisions, where the steel profiles for the members are selected from a table of steel sections, turns out to be a discrete nonlinear programming problem. Finding the optimum design of such design optimization problems using classical optimization techniques is difficult. Metaheuristic algorithms provide an alternative way of solving such problems. The firefly algorithm (FFA) belongs to the swarm intelligence group of metaheuristics. The standard FFA has the drawback of being caught up in local optima in large-sized steel frame design problems. This study attempts to enhance the performance of the FFA by suggesting two new expressions for the attractiveness and randomness parameters of the algorithm. Two real-world-sized design examples are designed by the enhanced FFA and its performance is compared with standard FFA as well as with particle swarm and cuckoo search algorithms.

Limit states and reliability-based pipeline design. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zimmerman, T.J.E.; Chen, Q.; Pandey, M.D.

1997-06-01

This report provides the results of a study to develop limit states design (LSD) procedures for pipelines. Limit states design, also known as load and resistance factor design (LRFD), provides a unified approach to dealing with all relevant failure modes combinations of concern. It explicitly accounts for the uncertainties that naturally occur in the determination of the loads which act on a pipeline and in the resistance of the pipe to failure. The load and resistance factors used are based on reliability considerations; however, the designer is not faced with carrying out probabilistic calculations. This work is done during developmentmore » and periodic updating of the LSD document. This report provides background information concerning limits states and reliability-based design (Section 2), gives the limit states design procedures that were developed (Section 3) and provides results of the reliability analyses that were undertaken in order to partially calibrate the LSD method (Section 4). An appendix contains LSD design examples in order to demonstrate use of the method. Section 3, Limit States Design has been written in the format of a recommended practice. It has been structured so that, in future, it can easily be converted to a limit states design code format. Throughout the report, figures and tables are given at the end of each section, with the exception of Section 3, where to facilitate understanding of the LSD method, they have been included with the text.« less

Probabilistic model of bridge vehicle loads in port area based on in-situ load testing

NASA Astrophysics Data System (ADS)

Deng, Ming; Wang, Lei; Zhang, Jianren; Wang, Rei; Yan, Yanhong

2017-11-01

Vehicle load is an important factor affecting the safety and usability of bridges. An statistical analysis is carried out in this paper to investigate the vehicle load data of Tianjin Haibin highway in Tianjin port of China, which are collected by the Weigh-in- Motion (WIM) system. Following this, the effect of the vehicle load on test bridge is calculated, and then compared with the calculation result according to HL-93(AASHTO LRFD). Results show that the overall vehicle load follows a distribution with a weighted sum of four normal distributions. The maximum vehicle load during the design reference period follows a type I extremum distribution. The vehicle load effect also follows a weighted sum of four normal distributions, and the standard value of the vehicle load is recommended as 1.8 times that of the calculated value according to HL-93.

Bending and Shear Behavior of Pultruded Glass Fiber Reinforced Polymer Composite Beams With Closed and Open Sections

NASA Astrophysics Data System (ADS)

Estep, Daniel Douglas

Several advantages, such as high strength-to-weight ratio, high stiffness, superior corrosion resistance, and high fatigue and impact resistance, among others, make FRPs an attractive alternative to conventional construction materials for use in developing new structures as well as rehabilitating in-service infrastructure. As the number of infrastructure applications using FRPs grows, the need for the development of a uniform Load and Resistance Factor Design (LRFD) approach, including design procedures and examples, has become paramount. Step-by-step design procedures and easy-to-use design formulas are necessary to assure the quality and safety of FRP structural systems by reducing the possibility of design and construction errors. Since 2008, the American Society of Civil Engineers (ASCE), in coordination with the American Composites Manufacturers Association (ACMA), has overseen the development of the Pre-Standard for Load and Resistance Factor Design (LRFD) of Pultruded Fiber Reinforced Polymer (FRP) Structures using probability-based limit states design. The fifth chapter of the pre-standard focuses on the design of members in flexure and shear under different failure modes, where the current failure load prediction models proposed within have been shown to be highly inaccurate based on experimental data and evaluation performed by researchers at the West Virginia University Constructed Facilities Center. A new prediction model for determining the critical flexural load capacity of pultruded GFRP square and rectangular box beams is presented within. This model shows that the type of failure can be related to threshold values of the beam span-to-depth ratio (L/h) and total flange width-to-thickness ratio (bf /t), resulting in three governing modes of failure: local buckling failure in the compression flange (4 ≤ L/h < 6), combined strain failure at the web-flange junction (6 ≤ L/h ≤ 10), and bending failure in the tension flange (10 < L/h ≤ 42). Broadly, the proposed equations are predicting critical flexural load capacities within +/-22.3% of experimental data for all cases, with over 70% of all experimental data with within +/-10% error. A second prediction model was developed for predicting the critical lateral-torsional buckling (LTB) load for pultruded GFRP open sections, including wide flange (WF) sections and channels. Multiple LTB equations from several sources were considered and applied but yielded inaccurate results, leading to the development of this new critical buckling load prediction model based on the well-established elastic LTB strength equation for steel. By making a series of modifications to equations for calculating the weak axis moment of inertia, torsional warping constant, and torsion constant for open sections, as well as recognizing the influence of the shear lag phenomenon, the critical LTB load is predicted within +/-15.2% of experimental data for all channel and WF specimens tested and evaluated in the study.

A Methodology for Multihazards Load Combinations of Earthquake and Heavy Trucks for Bridges

PubMed Central

Wang, Xu; Sun, Baitao

2014-01-01

Issues of load combinations of earthquakes and heavy trucks are important contents in multihazards bridge design. Current load resistance factor design (LRFD) specifications usually treat extreme hazards alone and have no probabilistic basis in extreme load combinations. Earthquake load and heavy truck load are considered as random processes with respective characteristics, and the maximum combined load is not the simple superimposition of their maximum loads. Traditional Ferry Borges-Castaneda model that considers load lasting duration and occurrence probability well describes random process converting to random variables and load combinations, but this model has strict constraint in time interval selection to obtain precise results. Turkstra's rule considers one load reaching its maximum value in bridge's service life combined with another load with its instantaneous value (or mean value), which looks more rational, but the results are generally unconservative. Therefore, a modified model is presented here considering both advantages of Ferry Borges-Castaneda's model and Turkstra's rule. The modified model is based on conditional probability, which can convert random process to random variables relatively easily and consider the nonmaximum factor in load combinations. Earthquake load and heavy truck load combinations are employed to illustrate the model. Finally, the results of a numerical simulation are used to verify the feasibility and rationality of the model. PMID:24883347

Calibration of region-specific gates pile driving formula for LRFD : final report 561.

DOT National Transportation Integrated Search

2016-05-01

This research project proposes new DOTD pile driving formulas for pile capacity verification using pile driving blow : counts obtained at either end-of-initial driving (EOID) or at the beginning-of-restrike (BOR). The pile driving : formulas were dev...

75 FR 27428 - Safety Standards for Steel Erection

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-17

... in National Highway System construction projects to comply with a number of standards, policies, and...://www.fhwa.dot.gov/bridge/lrfd/index.htm .) For projects involving bridge construction (e.g., temporary... of these requirements will enhance the safety of employees operating on or near structural steel...

Development of a real-time bridge structural monitoring and warning system: a case study in Thailand

NASA Astrophysics Data System (ADS)

Khemapech, I.; Sansrimahachai, W.; Toachoodee, M.

2017-04-01

Regarded as one of the physical aspects under societal and civil development and evolution, engineering structure is required to support growth of the nation. It also impacts life quality and safety of the civilian. Despite of its own weight (dead load) and live load, structural members are also significantly affected by disaster and environment. Proper inspection and detection are thus crucial both during regular and unsafe events. An Enhanced Structural Health Monitoring System Using Stream Processing and Artificial Neural Network Techniques (SPANNeT) has been developed and is described in this paper. SPANNeT applies wireless sensor network, real-time data stream processing and artificial neural network based upon the measured bending strains. Major contributions include an effective, accurate and energy-aware data communication and damage detection of the engineering structure. Strain thresholds have been defined according to computer simulation results and the AASHTO (American Association of State Highway and Transportation Officials) LRFD (Load and Resistance Factor Design) Bridge Design specifications for launching several warning levels. SPANNeT has been tested and evaluated by means of computer-based simulation and on-site levels. According to the measurements, the observed maximum values are 25 to 30 microstrains during normal operation. The given protocol provided at least 90% of data communication reliability. SPANNeT is capable of real-time data report, monitoring and warning efficiently conforming to the predefined thresholds which can be adjusted regarding user's requirements and structural engineering characteristics.

Evaluation of seismic design spectrum based on UHS implementing fourth-generation seismic hazard maps of Canada

NASA Astrophysics Data System (ADS)

Ahmed, Ali; Hasan, Rafiq; Pekau, Oscar A.

2016-12-01

Two recent developments have come into the forefront with reference to updating the seismic design provisions for codes: (1) publication of new seismic hazard maps for Canada by the Geological Survey of Canada, and (2) emergence of the concept of new spectral format outdating the conventional standardized spectral format. The fourth -generation seismic hazard maps are based on enriched seismic data, enhanced knowledge of regional seismicity and improved seismic hazard modeling techniques. Therefore, the new maps are more accurate and need to incorporate into the Canadian Highway Bridge Design Code (CHBDC) for its next edition similar to its building counterpart National Building Code of Canada (NBCC). In fact, the code writers expressed similar intentions with comments in the commentary of CHBCD 2006. During the process of updating codes, NBCC, and AASHTO Guide Specifications for LRFD Seismic Bridge Design, American Association of State Highway and Transportation Officials, Washington (2009) lowered the probability level from 10 to 2% and 10 to 5%, respectively. This study has brought five sets of hazard maps corresponding to 2%, 5% and 10% probability of exceedance in 50 years developed by the GSC under investigation. To have a sound statistical inference, 389 Canadian cities are selected. This study shows the implications of the changes of new hazard maps on the design process (i.e., extent of magnification or reduction of the design forces).

A Brillouin smart FRP material and a strain data post processing software for structural health monitoring through laboratory testing and field application on a highway bridge

NASA Astrophysics Data System (ADS)

Bastianini, Filippo; Matta, Fabio; Galati, Nestore; Nanni, Antonio

2005-05-01

Strain and temperature sensing obtained through frequency shift evaluation of Brillouin scattered light is a technology that seems extremely promising for Structural Health Monitoring (SHM). Due to the intrinsic distributed sensing capability, Brillouin can measure the deformation of any individual segment of huge lengths of inexpensive single-mode fiber. In addition, Brillouin retains other typical advantages of Fiber Optic Sensors (FOS), such as harsh environment durability and interference rejection. Despite these advantages, the diffusion of Brillouin for SHM is constrained by different factors, such as the high equipment cost, the commercial unavailability of specific SHM oriented fiber products and even some prejudices on the required sensitivity performances. In the present work, a complete SHM pilot application was developed, installed and successfully operated during a diagnostic load test on the High Performance Steel (HPS) bridge A6358 located at the Lake of the Ozarks (Miller County, MO, USA). Four out of five girders were extensively instrumented with a "smart" Glass Fiber Reinforced Polymer (GFRP) tape having embedded fibers for strain sensing and thermal compensation. Data collected during a diagnostic load test were elaborated through a specific post-processing software, and the strain profiles retrieved were compared to traditional strain gauges and theoretical results based on the AASHTO LRFD Bridge Design Specifications for structural assessment purposes. The excellent results obtained confirm the effectiveness of Brillouin SHM systems for the monitoring of real applications.

Improved Simplified Methods for Effective Seismic Analysis and Design of Isolated and Damped Bridges in Western and Eastern North America

NASA Astrophysics Data System (ADS)

Koval, Viacheslav

The seismic design provisions of the CSA-S6 Canadian Highway Bridge Design Code and the AASHTO LRFD Seismic Bridge Design Specifications have been developed primarily based on historical earthquake events that have occurred along the west coast of North America. For the design of seismic isolation systems, these codes include simplified analysis and design methods. The appropriateness and range of application of these methods are investigated through extensive parametric nonlinear time history analyses in this thesis. It was found that there is a need to adjust existing design guidelines to better capture the expected nonlinear response of isolated bridges. For isolated bridges located in eastern North America, new damping coefficients are proposed. The applicability limits of the code-based simplified methods have been redefined to ensure that the modified method will lead to conservative results and that a wider range of seismically isolated bridges can be covered by this method. The possibility of further improving current simplified code methods was also examined. By transforming the quantity of allocated energy into a displacement contribution, an idealized analytical solution is proposed as a new simplified design method. This method realistically reflects the effects of ground-motion and system design parameters, including the effects of a drifted oscillation center. The proposed method is therefore more appropriate than current existing simplified methods and can be applicable to isolation systems exhibiting a wider range of properties. A multi-level-hazard performance matrix has been adopted by different seismic provisions worldwide and will be incorporated into the new edition of the Canadian CSA-S6-14 Bridge Design code. However, the combined effect and optimal use of isolation and supplemental damping devices in bridges have not been fully exploited yet to achieve enhanced performance under different levels of seismic hazard. A novel Dual-Level Seismic Protection (DLSP) concept is proposed and developed in this thesis which permits to achieve optimum seismic performance with combined isolation and supplemental damping devices in bridges. This concept is shown to represent an attractive design approach for both the upgrade of existing seismically deficient bridges and the design of new isolated bridges.

Simultaneous Detection and Classification of Acoustic Emissions in Integrated Diagnostics with Yield in Aluminum

NASA Astrophysics Data System (ADS)

Parmar, Devendra

2006-04-01

Acoustic emission (AE) experiments were conducted on a strained aluminum (10 cm x 9 cm x 0.25 cm) specimen. Studies were conducted with the goal to characterize AE associated with material yield developed due to high loading and to correlate the course of the yield with AE signals. The American Association of State Highway and Transport Officials (AASHTO) listed aluminum as one of the structural components of highway brides^1 with unit weight of 2800 kg.m-3. The specimen, mounted on the load frame, was held on each end by the wedge grips and was electromechanically tested in a tension mode at rates of extension of 0.0333 mm/s and 0.0666 mm/s. Load was applied to the test frame via moving cross heads. A load transducer (load cell) mounted in series with the specimen measured the applied load by converting it into an electrical signal. Results are analyzed using defect zone model in which location of the defect is determined from the measurement of the arrival time of the signal at two different sensors placed at strategically around the source of emission from the test object. The sensor that detects the signal first is identified to be in the defect zone. ^1AASHTO LRFD Bridge Design Specifications, 1994.

Experimental design methods for bioengineering applications.

PubMed

Keskin Gündoğdu, Tuğba; Deniz, İrem; Çalışkan, Gülizar; Şahin, Erdem Sefa; Azbar, Nuri

2016-01-01

Experimental design is a form of process analysis in which certain factors are selected to obtain the desired responses of interest. It may also be used for the determination of the effects of various independent factors on a dependent factor. The bioengineering discipline includes many different areas of scientific interest, and each study area is affected and governed by many different factors. Briefly analyzing the important factors and selecting an experimental design for optimization are very effective tools for the design of any bioprocess under question. This review summarizes experimental design methods that can be used to investigate various factors relating to bioengineering processes. The experimental methods generally used in bioengineering are as follows: full factorial design, fractional factorial design, Plackett-Burman design, Taguchi design, Box-Behnken design and central composite design. These design methods are briefly introduced, and then the application of these design methods to study different bioengineering processes is analyzed.

The telerobot workstation testbed for the shuttle aft flight deck: A project plan for integrating human factors into system design

NASA Technical Reports Server (NTRS)

Sauerwein, Timothy

1989-01-01

The human factors design process in developing a shuttle orbiter aft flight deck workstation testbed is described. In developing an operator workstation to control various laboratory telerobots, strong elements of human factors engineering and ergonomics are integrated into the design process. The integration of human factors is performed by incorporating user feedback at key stages in the project life-cycle. An operator centered design approach helps insure the system users are working with the system designer in the design and operation of the system. The design methodology is presented along with the results of the design and the solutions regarding human factors design principles.

Satisfiers and Dissatisfiers: A Two-Factor Model for Website Design and Evaluation.

ERIC Educational Resources Information Center

Zhang, Ping; von Dran, Gisela M.

2000-01-01

Investigates Web site design factors and their impact from a theoretical perspective. Presents a two-factor model that can guide Web site design and evaluation. According to the model, there are two types of design factors: hygiene and motivator. Results showed that the two-factor model provides a means for Web-user interface studies. Provides…

33 CFR 156.230 - Factors considered in designating lightering zones.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Factors considered in designating... Lightering of Oil and Hazardous Material Cargoes § 156.230 Factors considered in designating lightering zones. The following factors are considered in designating a lightering zone: (a) The findings of the...

33 CFR 156.230 - Factors considered in designating lightering zones.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Factors considered in designating... Lightering of Oil and Hazardous Material Cargoes § 156.230 Factors considered in designating lightering zones. The following factors are considered in designating a lightering zone: (a) The findings of the...

33 CFR 156.230 - Factors considered in designating lightering zones.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Factors considered in designating... Lightering of Oil and Hazardous Material Cargoes § 156.230 Factors considered in designating lightering zones. The following factors are considered in designating a lightering zone: (a) The findings of the...

33 CFR 156.230 - Factors considered in designating lightering zones.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Factors considered in designating... Lightering of Oil and Hazardous Material Cargoes § 156.230 Factors considered in designating lightering zones. The following factors are considered in designating a lightering zone: (a) The findings of the...

33 CFR 156.230 - Factors considered in designating lightering zones.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Factors considered in designating... Lightering of Oil and Hazardous Material Cargoes § 156.230 Factors considered in designating lightering zones. The following factors are considered in designating a lightering zone: (a) The findings of the...

Design for Deconstruction (DfD): Critical success factors for diverting end-of-life waste from landfills.

PubMed

Akinade, Olugbenga O; Oyedele, Lukumon O; Ajayi, Saheed O; Bilal, Muhammad; Alaka, Hafiz A; Owolabi, Hakeem A; Bello, Sururah A; Jaiyeoba, Babatunde E; Kadiri, Kabir O

2017-02-01

The aim of this paper is to identify Critical Success Factors (CSF) needed for effective material recovery through Design for Deconstruction (DfD). The research approach employed in this paper is based on a sequential exploratory mixed method strategy. After a thorough review of literature and conducting four Focus Group Discussion (FGDs), 43 DfD factors were identified and put together in a questionnaire survey. Data analyses include Cronbach's alpha reliability analysis, mean testing using significance index, and exploratory factor analysis. The result of the factor analysis reveals that an underlying factor structure of five DfD factors groups that include 'stringent legislation and policy', 'deconstruction design process and competencies', 'design for material recovery', 'design for material reuse', and 'design for building flexibility'. These groups of DfD factor groups show that the requirements for DfD goes beyond technical competencies and that non-technical factors such as stringent legislation and policy and design process and competency for deconstruction are key in designing deconstructable buildings. Paying attention to the factors identified in all of these categories will help to tackle impediments that could hinder the effectiveness of DfD. The results of this study would help design and project managers to understand areas of possible improvement in employing DfD as a strategy for diverting waste from landfills. Copyright © 2016 Elsevier Ltd. All rights reserved.

24 CFR 598.305 - Designation factors.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 24 Housing and Urban Development 3 2014-04-01 2013-04-01 true Designation factors. 598.305 Section 598.305 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued... § 598.305 Designation factors. In choosing among nominated urban areas eligible for designation, the...

24 CFR 598.305 - Designation factors.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 24 Housing and Urban Development 3 2013-04-01 2013-04-01 false Designation factors. 598.305 Section 598.305 Housing and Urban Development Regulations Relating to Housing and Urban Development... Designation Process § 598.305 Designation factors. In choosing among nominated urban areas eligible for...

24 CFR 598.305 - Designation factors.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 24 Housing and Urban Development 3 2012-04-01 2012-04-01 false Designation factors. 598.305 Section 598.305 Housing and Urban Development Regulations Relating to Housing and Urban Development... Designation Process § 598.305 Designation factors. In choosing among nominated urban areas eligible for...

A Rule Based Approach to ISS Interior Volume Control and Layout

NASA Technical Reports Server (NTRS)

Peacock, Brian; Maida, Jim; Fitts, David; Dory, Jonathan

2001-01-01

Traditional human factors design involves the development of human factors requirements based on a desire to accommodate a certain percentage of the intended user population. As the product is developed human factors evaluation involves comparison between the resulting design and the specifications. Sometimes performance metrics are involved that allow leniency in the design requirements given that the human performance result is satisfactory. Clearly such approaches may work but they give rise to uncertainty and negotiation. An alternative approach is to adopt human factors design rules that articulate a range of each design continuum over which there are varying outcome expectations and interactions with other variables, including time. These rules are based on a consensus of human factors specialists, designers, managers and customers. The International Space Station faces exactly this challenge in interior volume control, which is based on anthropometric, performance and subjective preference criteria. This paper describes the traditional approach and then proposes a rule-based alternative. The proposed rules involve spatial, temporal and importance dimensions. If successful this rule-based concept could be applied to many traditional human factors design variables and could lead to a more effective and efficient contribution of human factors input to the design process.

Practicing universal design to actual hand tool design process.

PubMed

Lin, Kai-Chieh; Wu, Chih-Fu

2015-09-01

UD evaluation principles are difficult to implement in product design. This study proposes a methodology for implementing UD in the design process through user participation. The original UD principles and user experience are used to develop the evaluation items. Difference of product types was considered. Factor analysis and Quantification theory type I were used to eliminate considered inappropriate evaluation items and to examine the relationship between evaluation items and product design factors. Product design specifications were established for verification. The results showed that converting user evaluation into crucial design verification factors by the generalized evaluation scale based on product attributes as well as the design factors applications in product design can improve users' UD evaluation. The design process of this study is expected to contribute to user-centered UD application. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Analytic Couple Modeling Introducing Device Design Factor, Fin Factor, Thermal Diffusivity Factor, and Inductance Factor

NASA Technical Reports Server (NTRS)

Mackey, Jon; Sehirlioglu, Alp; Dynys, Fred

2014-01-01

A set of convenient thermoelectric device solutions have been derived in order to capture a number of factors which are previously only resolved with numerical techniques. The concise conversion efficiency equations derived from governing equations provide intuitive and straight-forward design guidelines. These guidelines allow for better device design without requiring detailed numerical modeling. The analytical modeling accounts for factors such as i) variable temperature boundary conditions, ii) lateral heat transfer, iii) temperature variable material properties, and iv) transient operation. New dimensionless parameters, similar to the figure of merit, are introduced including the device design factor, fin factor, thermal diffusivity factor, and inductance factor. These new device factors allow for the straight-forward description of phenomenon generally only captured with numerical work otherwise. As an example a device design factor of 0.38, which accounts for thermal resistance of the hot and cold shoes, can be used to calculate a conversion efficiency of 2.28 while the ideal conversion efficiency based on figure of merit alone would be 6.15. Likewise an ideal couple with efficiency of 6.15 will be reduced to 5.33 when lateral heat is accounted for with a fin factor of 1.0.

Revisiting classical design in engineering from a perspective of frugality.

PubMed

Rao, Balkrishna C

2017-05-01

The conservative nature of design in engineering has typically unleashed products fabricated with generous amounts of raw materials. This is epitomized by the factor of safety whose values higher than unity suggests various uncertainties of design that are tackled through material padding. This effort proposes a new factor of safety called the factor of frugality that could be used in ecodesign and which addresses both rigors of the classical design process and quantification of savings in materials going into a product. An example of frugal shaft design together with some other cases has been presented to explain the working of the factor of frugality . Adoption of the frugality factor would entail a change in design philosophy whereby designers would constantly make avail of a rigorous design process coupled with material-saving schemes for realizing products that are benign to the environment. Such a change in the foundations of design would abet the stewardship of earth in avoiding planetary boundaries since engineering influences a significant proportion of human endeavors.

Factors That Shape Design Thinking

ERIC Educational Resources Information Center

Gray, Colin M.

2013-01-01

A wide range of design literature discusses the role of the studio and its related pedagogy in the development of design thinking. Scholars in a variety of design disciplines pose a number of factors that potentially affect this development process, but a full understanding of these factors as experienced from a critical pedagogy or student…

FACTORS INFLUENCING THE DESIGN OF BIOACCUMULATION FACTOR AND BIOTA-SEDIMENT ACCUMULATION FACTOR FIELD STUDIES

EPA Science Inventory

A series of modeling simulations were performed to develop an understanding of the underlying factors and principles involved in developing field sampling designs for measuring bioaccumulation factors (BAFs) and biota-sediment accumulation factors (BSAFs. These simulations reveal...

Human Factors Considerations in System Design

NASA Technical Reports Server (NTRS)

Mitchell, C. M. (Editor); Vanbalen, P. M. (Editor); Moe, K. L. (Editor)

1983-01-01

Human factors considerations in systems design was examined. Human factors in automated command and control, in the efficiency of the human computer interface and system effectiveness are outlined. The following topics are discussed: human factors aspects of control room design; design of interactive systems; human computer dialogue, interaction tasks and techniques; guidelines on ergonomic aspects of control rooms and highly automated environments; system engineering for control by humans; conceptual models of information processing; information display and interaction in real time environments.

Introduction to human factors considerations in system design

NASA Technical Reports Server (NTRS)

Chapanis, A.

1983-01-01

A definition for human factors or ergonomics and its industrial and domestic application is presented. Human factors engineering, which discovers and applies information about human abilities, limitations, and other characteristics to the design of tools, machines, systems, tasks, jobs, and environments for safe, comfortable, and effective human use, is outlined. The origins of human factors and ergonomics, the philosophy of human factors, goals and objectives, systems development and design, are reviewed.

FACTORS INFLUENCING THE DESIGN OF BIOACCUMULATION FACTOR AND BIOTA-SEDIMENT ACCUMULATION FACTOR FIELD STUDIES

EPA Science Inventory

General guidance for designing field studies to measure bioaccumulation factors (BAFs) and biota-sediment accumulation factors (BSAFs) is not available. To develop such guidance, a series of modeling simulations were performed to evaluate the underlying factors and principles th...

Applications of Human Factors in Space

NASA Technical Reports Server (NTRS)

Rajulu, Sudhakar; Margerum, Sarah

2008-01-01

The main question for human factors practitioners is to determine if the user population can be accommodated within a design. Given the wide range of variables feeding into a design, just one of which is human factors, oftentimes designers will have restrictions that may potentially impact the level of accommodation. This paper focuses on two case studies where there have been impacts at the design level that may be detrimental to the ability of the design to meet certain criteria. The studies use novel approaches to determine what, if any, changes in population accommodation levels have occurred and what factors are important when manipulating the design in the future. The results of these studies provide a backbone for future analyses when working with design considerations.

Risk factors and study designs used in research of youths' suicide behaviour-an epidemiological discussion with focus on level of evidence.

PubMed

Christiansen, Erik; Larsen, Kim Juul; Agerbo, Esben; Bilenberg, Niels; Stenager, Elsebeth

2014-11-01

Abstract Introduction: Many different epidemiology study designs have been used to analyse risk factors for suicide behaviour. The purpose of this study was to obtain an insight into the current study design used in research on youths' risk factors for suicide behaviour and to rank the studies according to level of evidence (LoE). We searched PubMed and psycINFO in order to identify relevant individual studies. We included 36 studies of children and youth on suicidal behaviour and ideation-many rank low on LoE. For suicide, cohort design was often used, and mental illness (depression, substance abuse and severity of mental illness) was the most common risk factor. Cohort studies are ranked 2b, which is high according to LoE. For suicide attempts, survey was often used, and psychopathology, substance abuse and being exposed to suicidal behaviour were the most common risk factors. For suicidal ideation, survey was the only design used, and substance abuse and psychopathology the most common risk factors. Surveys are ranked 4, which are low according to LoE. Many risk factors were broad and unspecific, and standard definitions of outcome and exposure were rarely used. A good study of risk factors for suicidal behaviour would need a high LoE, as a high-powered longitudinal epidemiological study (cohort or case-control) of very specific risk factors. The factors would have high prevention potential, compared with more broad and unspecific risk factors, to which many people are exposed. We would recommend a cohort design (in high-risk populations) or a case-control design to identify risk factors, using clinical and/or register data instead of self-reported information, reporting adjusted estimates and using standard definition of suicidal outcome and risk factors.

Human-factors engineering control-room design review/audit: Waterford 3 SES Generating Station, Louisiana Power and Light Company

DOE Office of Scientific and Technical Information (OSTI.GOV)

Savage, J.W.

1983-03-10

A human factors engineering design review/audit of the Waterford-3 control room was performed at the site on May 10 through May 13, 1982. The report was prepared on the basis of the HFEB's review of the applicant's Preliminary Human Engineering Discrepancy (PHED) report and the human factors engineering design review performed at the site. This design review was carried out by a team from the Human Factors Engineering Branch, Division of Human Factors Safety. The review team was assisted by consultants from Lawrence Livermore National Laboratory (University of California), Livermore, California.

Securing Public Safety Vehicles: Reducing Vulnerabilities by Leveraging Smart Technology and Design Strategies

DTIC Science & Technology

2013-12-01

Protective Equipment Sizing and Design ,” Human Factors: The Journal of the Human Factors and Ergonomics Society 55, no. 1 (2013): 6–35; Hsiao...firefighters. The information will be used to improve apparatus design , revise NFPA 1901 Standard for Automotive Fire Apparatus, and improve cab, seat ... Design .” Human Factors: The Journal of the Human Factors and Ergonomics Society 55, no. 1 (2013): 6–35. ———. Sizing Firefighters and Fire Apparatus

Form Factor Evaluation of Open Body Area Network (OBAN) Physiological Status Monitoring (PSM) System Prototype Designs

DTIC Science & Technology

2018-05-11

SYSTEM PROTOTYPE DESIGNS DISCLAIMERS The opinions or assertions contained herein are the private views of the author(s) and are not to be construed as...FORM FACTOR EVALUATION OF OPEN BODY AREA NETWORK (OBAN) PHYSIOLOGICAL STATUS MONITORING (PSM) SYSTEM PROTOTYPE DESIGNS William J...security; and is designed to function for 72 hours or more. The test described in this report assesses proposed form-factor designs . Feedback using

Human factors of intelligent computer aided display design

NASA Technical Reports Server (NTRS)

Hunt, R. M.

1985-01-01

Design concepts for a decision support system being studied at NASA Langley as an aid to visual display unit (VDU) designers are described. Ideally, human factors should be taken into account by VDU designers. In reality, although the human factors database on VDUs is small, such systems must be constantly developed. Human factors are therefore a secondary consideration. An expert system will thus serve mainly in an advisory capacity. Functions can include facilitating the design process by shortening the time to generate and alter drawings, enhancing the capability of breaking design requirements down into simpler functions, and providing visual displays equivalent to the final product. The VDU system could also discriminate, and display the difference, between designer decisions and machine inferences. The system could also aid in analyzing the effects of designer choices on future options and in ennunciating when there are data available on a design selections.

INCOMMANDS TDP: Human Factors Evaluation of the Command Decision Support Capability Prototype

DTIC Science & Technology

2009-03-01

CDSC) design with guidelines and principles stipulated in the INCOMMANDS TDP Human Factors Design and Evaluation Guide. 2. Usability and Utility...INCOMMANDS CDSC. The Heuristic Evaluation helps to ensure that the design of system is compliant with HCI best practices. Whereas the Usability and...implemented to confirm compliance with the INCOMMANDS TDP Human Factors Design and Evaluation Guide

Human Factors Checklist for the Design and Evaluation of Air Traffic Control Systems

DOT National Transportation Integrated Search

1995-04-01

This document presents human factors issues that should bo considered in tho : design and evaluation of air traffic control (ATC! systoms and subsystems. Tho : checklist is a companion document to Human Factors in tho Design and Evaluation of : Air T...

NASA Space Flight Human System Standards

NASA Technical Reports Server (NTRS)

Tillman, Barry; Pickett, Lynn; Russo, Dane; Stroud, Ken; Connolly, Jan; Foley, Tico

2007-01-01

NASA has begun a new approach to human factors design standards. For years NASA-STD-3000, Manned Systems Integration Standards, has been a source of human factors design guidance for space systems. In order to better meet the needs of the system developers, NASA is revising its human factors standards system. NASA-STD-3000 will be replaced by two documents: set of broad human systems specifications (including both human factors and medical topics) and a human factors design handbook

The Factors of Design on Playing Equipment in Young Children Schools by Viewpoint of Young Children Behavioral Development

ERIC Educational Resources Information Center

Kuo, Chuen-tzay

2009-01-01

The main purpose of this study was to explore the care-givers of preschool education institutions whose cognition on playing equipment functions, conditions of both setting and using, and the main factors which should beware of design. Besides, not only constructed the factors of design, but also provided suggestions about setting and designing of…

Assessment of seismic design response factors of concrete wall buildings

NASA Astrophysics Data System (ADS)

Mwafy, Aman

2011-03-01

To verify the seismic design response factors of high-rise buildings, five reference structures, varying in height from 20- to 60-stories, were selected and designed according to modern design codes to represent a wide range of concrete wall structures. Verified fiber-based analytical models for inelastic simulation were developed, considering the geometric nonlinearity and material inelasticity of the structural members. The ground motion uncertainty was accounted for by employing 20 earthquake records representing two seismic scenarios, consistent with the latest understanding of the tectonic setting and seismicity of the selected reference region (UAE). A large number of Inelastic Pushover Analyses (IPAs) and Incremental Dynamic Collapse Analyses (IDCAs) were deployed for the reference structures to estimate the seismic design response factors. It is concluded that the factors adopted by the design code are adequately conservative. The results of this systematic assessment of seismic design response factors apply to a wide variety of contemporary concrete wall buildings with various characteristics.

Preliminary Sizing Study of Ares-I and Ares-V Liquid Hydrogen Tanks

NASA Technical Reports Server (NTRS)

Oliver, Stanley T.; Harper, David W.

2012-01-01

A preliminary sizing study of two cryogenic propellant tanks was performed using a FORTRAN optimization program to determine weight efficient orthogrid designs for the tank barrels sections only. Various tensile and compressive failure modes were considered, including general buckling of cylinders with a shell buckling knockdown factor. Eight independent combinations of three design requirements were also considered and their effects on the tanks weight. The approach was to investigate each design case with a variable shell buckling knockdown factor, determining the most weight efficient combination of orthogrid design parameters. Numerous optimization analyses were performed, and the results presented herein compare the effects of the different design requirements and shell buckling knockdown factor. Through a series of comparisons between design requirements or shell buckling knockdown factors, the relative change in overall tank barrel weights is shown. The findings indicate that the design requirements can substantually increase the tank weight while a less conservative shell buckling knockdown factor can modestly reduce the tank weight.

Human factors aspects of control room design: Guidelines and annotated bibliography

NASA Technical Reports Server (NTRS)

Mitchell, C. M.; Stewart, L. J.; Bocast, A. K.; Murphy, E. D.

1982-01-01

A human factors analysis of the workstation design for the Earth Radiation Budget Satellite mission operation room is discussed. The relevance of anthropometry, design rules, environmental design goals, and the social-psychological environment are discussed.

Parametric design of pressure-relieving foot orthosis using statistics-based finite element method.

PubMed

Cheung, Jason Tak-Man; Zhang, Ming

2008-04-01

Custom-molded foot orthoses are frequently prescribed in routine clinical practice to prevent or treat plantar ulcers in diabetes by reducing the peak plantar pressure. However, the design and fabrication of foot orthosis vary among clinical practitioners and manufacturers. Moreover, little information about the parametric effect of different combinations of design factors is available. As an alternative to the experimental approach, therefore, computational models of the foot and footwear can provide efficient evaluations of different combinations of structural and material design factors on plantar pressure distribution. In this study, a combined finite element and Taguchi method was used to identify the sensitivity of five design factors (arch type, insole and midsole thickness, insole and midsole stiffness) of foot orthosis on peak plantar pressure relief. From the FE predictions, the custom-molded shape was found to be the most important design factor in reducing peak plantar pressure. Besides the use of an arch-conforming foot orthosis, the insole stiffness was found to be the second most important factor for peak pressure reduction. Other design factors, such as insole thickness, midsole stiffness and midsole thickness, contributed to less important roles in peak pressure reduction in the given order. The statistics-based FE method was found to be an effective approach in evaluating and optimizing the design of foot orthosis.

Bayes factor design analysis: Planning for compelling evidence.

PubMed

Schönbrodt, Felix D; Wagenmakers, Eric-Jan

2018-02-01

A sizeable literature exists on the use of frequentist power analysis in the null-hypothesis significance testing (NHST) paradigm to facilitate the design of informative experiments. In contrast, there is almost no literature that discusses the design of experiments when Bayes factors (BFs) are used as a measure of evidence. Here we explore Bayes Factor Design Analysis (BFDA) as a useful tool to design studies for maximum efficiency and informativeness. We elaborate on three possible BF designs, (a) a fixed-n design, (b) an open-ended Sequential Bayes Factor (SBF) design, where researchers can test after each participant and can stop data collection whenever there is strong evidence for either [Formula: see text] or [Formula: see text], and (c) a modified SBF design that defines a maximal sample size where data collection is stopped regardless of the current state of evidence. We demonstrate how the properties of each design (i.e., expected strength of evidence, expected sample size, expected probability of misleading evidence, expected probability of weak evidence) can be evaluated using Monte Carlo simulations and equip researchers with the necessary information to compute their own Bayesian design analyses.

29 CFR 1918.62 - Miscellaneous auxiliary gear.

Code of Federal Regulations, 2010 CFR

2010-07-01

... appendix II to this part. A design safety factor of at least five shall be maintained for the common sizes... cranes, designed to be used with lesser wire rope safety factors; (ii) According to design factors in... pre-slung drafts. (3) Eye splices shall consist of at least three full tucks. Short splices shall...

29 CFR 1918.62 - Miscellaneous auxiliary gear.

Code of Federal Regulations, 2011 CFR

2011-07-01

... appendix II to this part. A design safety factor of at least five shall be maintained for the common sizes... cranes, designed to be used with lesser wire rope safety factors; (ii) According to design factors in... pre-slung drafts. (3) Eye splices shall consist of at least three full tucks. Short splices shall...

Organizational Learning and Product Design Management: Towards a Theoretical Model.

ERIC Educational Resources Information Center

Chiva-Gomez, Ricardo; Camison-Zornoza, Cesar; Lapiedra-Alcami, Rafael

2003-01-01

Case studies of four Spanish ceramics companies were used to construct a theoretical model of 14 factors essential to organizational learning. One set of factors is related to the conceptual-analytical phase of the product design process and the other to the creative-technical phase. All factors contributed to efficient product design management…

Design and Analysis of Subscale and Full-Scale Buckling-Critical Cylinders for Launch Vehicle Technology Development

NASA Technical Reports Server (NTRS)

Hilburger, Mark W.; Lovejoy, Andrew E.; Thornburgh, Robert P.; Rankin, Charles

2012-01-01

NASA s Shell Buckling Knockdown Factor (SBKF) project has the goal of developing new analysis-based shell buckling design factors (knockdown factors) and design and analysis technologies for launch vehicle structures. Preliminary design studies indicate that implementation of these new knockdown factors can enable significant reductions in mass and mass-growth in these vehicles. However, in order to validate any new analysis-based design data or methods, a series of carefully designed and executed structural tests are required at both the subscale and full-scale levels. This paper describes the design and analysis of three different orthogrid-stiffeNed metallic cylindrical-shell test articles. Two of the test articles are 8-ft-diameter, 6-ft-long test articles, and one test article is a 27.5-ft-diameter, 20-ft-long Space Shuttle External Tank-derived test article.

24 CFR 598.305 - Designation factors.

Code of Federal Regulations, 2010 CFR

2010-04-01

... (Continued) OFFICE OF ASSISTANT SECRETARY FOR COMMUNITY PLANNING AND DEVELOPMENT, DEPARTMENT OF HOUSING AND... Designation Process § 598.305 Designation factors. In choosing among nominated urban areas eligible for designation, the Secretary will consider: (a) Quality of strategic plan. The quality of the strategic plan...

Manpower Systems Integration Factors for Frigate Design in the Turkish Navy

DTIC Science & Technology

2016-12-01

factors for frigate design in the Turkish Navy. The qualitative and quantitative analyses of the correlation between ship design specifications and...frigates. The correlation between the ship design characteristics and the manpower requirements is supported by the quantitative analysis. This... design in the Turkish Navy. The qualitative and quantitative analyses of the correlation between ship design specifications and manpower requirements

Developing the Next Generation Shell Buckling Design Factors and Technologies

NASA Technical Reports Server (NTRS)

Hilburger, Mark W.

2012-01-01

NASA s Shell Buckling Knockdown Factor (SBKF) Project was established in the spring of 2007 by the NASA Engineering and Safety Center (NESC) in collaboration with the Constellation Program and Exploration Systems Mission Directorate. The SBKF project has the current goal of developing less-conservative, robust shell buckling design factors (a.k.a. knockdown factors) and design and analysis technologies for light-weight stiffened metallic launch vehicle (LV) structures. Preliminary design studies indicate that implementation of these new knockdown factors can enable significant reductions in mass and mass-growth in these vehicles and can help mitigate some of NASA s LV development and performance risks. In particular, it is expected that the results from this project will help reduce the reliance on testing, provide high-fidelity estimates of structural performance, reliability, robustness, and enable increased payload capability. The SBKF project objectives and approach used to develop and validate new design technologies are presented, and provide a glimpse into the future of design of the next generation of buckling-critical launch vehicle structures.

24 CFR 597.301 - Selection factors for designation of nominated urban areas.

Code of Federal Regulations, 2010 CFR

2010-04-01

... to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR COMMUNITY PLANNING AND... ENTERPRISE COMMUNITIES: ROUND ONE DESIGNATIONS Designation Process § 597.301 Selection factors for... for designation, the Secretary shall consider: (1) The effectiveness of the strategic plan in...

Influences of Display Design and Task Management Strategy on Situation Awareness, Performance, and Workload in Process Control Environments

DTIC Science & Technology

2014-12-26

and Ergonomics Society 54th Annual Meeting (pp. 284-288). Human Factors and Ergonomics Society. Miller, C. A., & Parasuraman, R. (2007). Designing ...Factors and Ergonomics Society, 37 (1), 32-64. Gould, J. (1988). How to design usable systems (excerpt). IBM Research Center Hawthorne. In M...Research Past, Present, and Future. Ergonomics in Design : The Quarterly of Human Factors Applications , 21(2), pp. 9-14. Handal, C., & Ikuma, L. H

Designing learning environments to promote student learning: ergonomics in all but name.

PubMed

Smith, Thomas J

2013-01-01

This report introduces evidence for the conclusion that a common theme underlies almost all proposed solutions for improving the performance of K-12 students, namely their reliance on the design of educational system environments, features and operations. Two categories of design factors impacting such performance are addressed: (1) 9 factors reliably shown to have a strong influence - namely environmental design of classroom and building facilities, longer exposure to learning, cooperative learning designs, early childhood education, teaching quality, nutritional adequacy, participation in physical activity, good physical fitness, and school-community integration; and (2) 11 factors with an equivocal, varied or weak influence - classroom technology, online learning environments, smaller class size, school choice, school funding, school size, school start times, teacher training level, amount of homework, student self-confidence and informal learning. It is concluded that: (1) student learning outcomes, and more broadly the edifice of education itself, are largely defined in terms of an extensive system of design factors and conditions; (2) the time is long overdue for the educational system to acknowledge the central role of E/HF design as the major influence on student performance and learning; and (3) K-12 educators and administrators should emphasize allocation of resources to design factors reliably shown to have a strongly positive impact on student performance, but should treat expenditure on factors with equivocal, varied or weak influence on such performance with more caution and/or skepticism.

A cautionary note on the use of the Analysis of Covariance (ANCOVA) in classification designs with and without within-subject factors

PubMed Central

Schneider, Bruce A.; Avivi-Reich, Meital; Mozuraitis, Mindaugas

2015-01-01

A number of statistical textbooks recommend using an analysis of covariance (ANCOVA) to control for the effects of extraneous factors that might influence the dependent measure of interest. However, it is not generally recognized that serious problems of interpretation can arise when the design contains comparisons of participants sampled from different populations (classification designs). Designs that include a comparison of younger and older adults, or a comparison of musicians and non-musicians are examples of classification designs. In such cases, estimates of differences among groups can be contaminated by differences in the covariate population means across groups. A second problem of interpretation will arise if the experimenter fails to center the covariate measures (subtracting the mean covariate score from each covariate score) whenever the design contains within-subject factors. Unless the covariate measures on the participants are centered, estimates of within-subject factors are distorted, and significant increases in Type I error rates, and/or losses in power can occur when evaluating the effects of within-subject factors. This paper: (1) alerts potential users of ANCOVA of the need to center the covariate measures when the design contains within-subject factors, and (2) indicates how they can avoid biases when one cannot assume that the expected value of the covariate measure is the same for all of the groups in a classification design. PMID:25954230

A guide to structural factors for advanced composites used on spacecraft

NASA Technical Reports Server (NTRS)

Vanwagenen, Robert

1989-01-01

The use of composite materials in spacecraft systems is constantly increasing. Although the areas of composite design and fabrication are maturing, they remain distinct from the same activities performed using conventional materials and processes. This has led to some confusion regarding the precise meaning of the term 'factor of safety' as it applies to these structures. In addition, composite engineering introduces terms such as 'knock-down factors' to further modify material properties for design purposes. This guide is intended to clarify these terms as well as their use in the design of composite structures for spacecraft. It is particularly intended to be used by the engineering community not involved in the day-to-day composites design process. An attempt is also made to explain the wide range of factors of safety encountered in composite designs as well as their relationship to the 1.4 factor of safety conventionally applied to metallic structures.

Preliminary human factors guidelines for automated highway system designers. Volume 1 : guidelines for AHS designers

DOT National Transportation Integrated Search

1998-04-01

Human factors can be defined as "designing to match the capabilities and limitations of the human user." The objectives of this human-centered design process are to maximize the effectiveness and efficiency of system performance, ensure a high level ...

Cultural factors influencing safety need to be addressed in design and operation of technology.

PubMed

Meshkati, N

1996-10-01

Cultural factors which influence aviation safety in aircraft design, air traffic control, and human factors training are examined. Analysis of the Avianca Flight 052 crash in New York in January, 1990, demonstrates the catastrosphic effects cultural factors can play. Cultural factors include attitude toward work and technology, organizational hierarchy, religion, and population stereotyping.

Report: Optimization study of the preparation factors for argan oil microcapsule based on hybrid-level orthogonal array design via SPSS modeling.

PubMed

Zhao, Xi; Wu, Xiaoli; Zhou, Hui; Jiang, Tao; Chen, Chun; Liu, Mingshi; Jin, Yuanbao; Yang, Dongsheng

2014-11-01

To optimize the preparation factors for argan oil microcapsule using complex coacervation of chitosan cross-linked with gelatin based on hybrid-level orthogonal array design via SPSS modeling. Eight relatively significant factors were firstly investigated and selected as calculative factors for the orthogonal array design from the total of ten factors effecting the preparation of argan oil microcapsule by utilizing the single factor variable method. The modeling of hybrid-level orthogonal array design was built in these eight factors with the relevant levels (9, 9, 9, 9, 7, 6, 2 and 2 respectively). The preparation factors for argan oil microcapsule were investigated and optimized according to the results of hybrid-level orthogonal array design. The priorities order and relevant optimum levels of preparation factors standard to base on the percentage of microcapsule with the diameter of 30~40 μm via SPSS. Experimental data showed that the optimum factors were controlling the chitosan/gelatin ratio, the systemic concentration and the core/shell ratio at 1:2, 1.5% and 1:7 respectively, presetting complex coacervation pH at 6.4, setting cross-linking time and complex coacervation at 75 min and 30 min, using the glucose-delta lactone as the type of cross-linking agent, and selecting chitosan with the molecular weight of 2000～3000.

Engineering Margin Factors Used in the Design of the VVER Fuel Cycles

NASA Astrophysics Data System (ADS)

Lizorkin, M. P.; Shishkov, L. K.

2017-12-01

The article describes methods for determination of the engineering margin factors currently used to estimate the uncertainties of the VVER reactor design parameters calculated via the KASKAD software package developed at the National Research Center Kurchatov Institute. These margin factors ensure the meeting of the operating (design) limits and a number of other restrictions under normal operating conditions.

Reengineering the JPL Spacecraft Design Process

NASA Technical Reports Server (NTRS)

Briggs, C.

1995-01-01

This presentation describes the factors that have emerged in the evolved process of reengineering the unmanned spacecraft design process at the Jet Propulsion Laboratory in Pasadena, California. Topics discussed include: New facilities, new design factors, new system-level tools, complex performance objectives, changing behaviors, design integration, leadership styles, and optimization.

Preliminary Human Factors Guidelines for Automated Highway System Designers, Second Edition - Volume 1: Guidelines for AHS Designers

DOT National Transportation Integrated Search

1998-04-01

Human factors can be defined as "designing to match the capabilities and limitations of the human user." The objectives of this human-centered design process are to maximize the effectiveness and efficiency of system performance, ensure a high level ...

Construction, Analysis, and Data-Driven Augmentation of Supersaturated Designs

DTIC Science & Technology

2013-09-01

guidelines and considerations. 27 Table 7. Supersaturated Design Example with 8 Runs and 14 Factors Design Factors Run x1 x2 x3 x4 x5 x6 x7 x8 x9 x10 x11...much larger than the guidelines proposed by Marley 55 and Woods (2010). They recommend the factor-to-run ratio should be less than 2. Because our ratio...established approach in experimental design: Box (1992) provided general guidelines to consider, and traditional augmentation strategies like fold-over

Towards viable, useful and usable human factors design guidance.

PubMed

Burns, C M; Vicente, K J; Christoffersen, K; Pawlak, W S

1997-01-01

This paper investigates the factors relevant to producing effective human factors design guidance, using the Engineering Data Compendium (EDC) as a research vehicle. A series of three exploratory experiments focusing on the factors that affect the usability, usefulness and viability of human factors handbooks was conducted. The results of these studies were interpreted in the context of the process by which the EDC was developed, leading to the following recommendations: (a) human factors guidance should be organized in a manner that is stepped in context; (b) human factors guidance should be based on an explicit requirements analysis; (c) the calibration of designers' perceptions of the cost of obtaining human factors information must be improved; (d) organizational policies must be changed to induce more effective information search behaviour.

49 CFR 192.111 - Design factor (F) for steel pipe.

Code of Federal Regulations, 2010 CFR

2010-10-01

... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Pipe Design § 192.111 Design factor (F... street, or a railroad; (3) Is supported by a vehicular, pedestrian, railroad, or pipeline bridge; or (4...

A review of human factors principles for the design and implementation of medication safety alerts in clinical information systems.

PubMed

Phansalkar, Shobha; Edworthy, Judy; Hellier, Elizabeth; Seger, Diane L; Schedlbauer, Angela; Avery, Anthony J; Bates, David W

2010-01-01

The objective of this review is to describe the implementation of human factors principles for the design of alerts in clinical information systems. First, we conduct a review of alarm systems to identify human factors principles that are employed in the design and implementation of alerts. Second, we review the medical informatics literature to provide examples of the implementation of human factors principles in current clinical information systems using alerts to provide medication decision support. Last, we suggest actionable recommendations for delivering effective clinical decision support using alerts. A review of studies from the medical informatics literature suggests that many basic human factors principles are not followed, possibly contributing to the lack of acceptance of alerts in clinical information systems. We evaluate the limitations of current alerting philosophies and provide recommendations for improving acceptance of alerts by incorporating human factors principles in their design.

The impact of visual layout factors on performance in Web pages: a cross-language study.

PubMed

Parush, Avi; Shwarts, Yonit; Shtub, Avy; Chandra, M Jeya

2005-01-01

Visual layout has a strong impact on performance and is a critical factor in the design of graphical user interfaces (GUIs) and Web pages. Many design guidelines employed in Web page design were inherited from human performance literature and GUI design studies and practices. However, few studies have investigated the more specific patterns of performance with Web pages that may reflect some differences between Web page and GUI design. We investigated interactions among four visual layout factors in Web page design (quantity of links, alignment, grouping indications, and density) in two experiments: one with pages in Hebrew, entailing right-to-left reading, and the other with English pages, entailing left-to-right reading. Some performance patterns (measured by search times and eye movements) were similar between languages. Performance was particularly poor in pages with many links and variable densities, but it improved with the presence of uniform density. Alignment was not shown to be a performance-enhancing factor. The findings are discussed in terms of the similarities and differences in the impact of layout factors between GUIs and Web pages. Actual or potential applications of this research include specific guidelines for Web page design.

Identifying crash contributory factors at urban roundabouts and using association rules to explore their relationships to different crash types.

PubMed

Montella, Alfonso

2011-07-01

The use of roundabouts improves intersection safety by eliminating or altering conflict types, reducing crash severity, and causing drivers to reduce speeds. However, roundabout performances can degrade if precautions are not taken during either the design or the operation phase. Therefore, additional information on the safety of the roundabouts is extremely helpful for planners and designers in identifying existing deficiencies and in refining the design criteria currently being used. The aim of the paper was to investigate the crash contributory factors in 15 urban roundabouts located in Italy and to study the interdependences between these factors. The crash data refer to the period 2003-2008. The identification of the crash contributory factors was based on site inspections and rigorous analyses performed by a team of specialists with a relevant road safety engineering background. Each roundabout was inspected once every year from 2004 to 2009, both in daytime and in nighttime. Overall, 62 different contributory factors and 2156 total contributory factors were identified. In 51 crashes, a single contributory factor was found, whereas in the other 223 crashes, a combination of contributory factors was identified. Given the large amount of data, the interdependences between the contributory factors and between the contributory factors and the different crash types were explored by an association discovery. Association discovery is the identification of sets of items (i.e., crash contributory factors and crash types in our study) that occur together in a given event (i.e., a crash in our study). The rules were filtered by support, confidence, and lift. As a result, 112 association rules were discovered. Overall, numerous contributory factors related to the road and environment deficiencies but not related to the road user or to the vehicle were identified. The most important factors related to geometric design were the radius of deflection and the deviation angle. In existing roundabouts, the improvement of these factors might be quite expensive, but the crucial role of a moderate radius of deflection and a large deviation angle in the design of new roundabouts was stressed. Many of the contributory factors were related to markings and signs, and these factors could be easily removed with low-cost safety measures. Furthermore, because of the association between the markings, signs, and geometric design contributory factors, the study results suggest that the improvement in markings and signs might also have a significant effect in the sites where geometric design deficiencies were identified as contributory factors. Copyright © 2011 Elsevier Ltd. All rights reserved.

ENVIRONMENTAL COMPARISON METRICS FOR LIFE CYCLE IMPACT ASSESSMENT AND PROCESS DESIGN

EPA Science Inventory

Metrics (potentials, potency factors, equivalency factors or characterization factors) are available to support the environmental comparison of alternatives in application domains like proces design and product life-cycle assessment (LCA). These metrics typically provide relative...

Designing action games for appealing to buyers.

PubMed

Hsu, Shang Hwa; Lee, Feng-Liang; Wu, Muh-Cherng

2005-12-01

This study aims to identify design features for action games that would appeal to game-buyers, rather than game-players. Sixteen frequent-buyers of computer games identified 39 design features that appeal to buyers by contrasting different versions of Pacman games. Twenty-eight versions of Pacman were then evaluated in terms of the identified design features by 45 participants (27 male and 18 female college students). Qnet2000 neural network software was used to determine the relative importance of these design features. The results indicated that the top 10 most important design features could account for more than 50% of "perceived fun" among these 39 design features. The feature of avatar is important to game-buyers, yet not revealed in previous player-oriented studies. Moreover, six design factors underlying the 39 features were identified through factor analysis. These factors included "novelty and powerfulness," "appealing presentation," "interactivity," "challenging," "sense of control," and "rewarding," and could account for 54% of total variance. Among these six factors, appealing presentation has not been emphasized by player-oriented research. Implications of the findings were discussed.

Effects of Spatial Experiences & Cognitive Styles in the Solution Process of Space-Based Design Problems in the First Year of Architectural Design Education

ERIC Educational Resources Information Center

Erkan Yazici, Yasemin

2013-01-01

There are many factors that influence designers in the architectural design process. Cognitive style, which varies according to the cognitive structure of persons, and spatial experience, which is created with spatial data acquired during life are two of these factors. Designers usually refer to their spatial experiences in order to find solutions…

Structural design/margin assessment

NASA Technical Reports Server (NTRS)

Ryan, R. S.

1993-01-01

Determining structural design inputs and the structural margins following design completion is one of the major activities in space exploration. The end result is a statement of these margins as stability, safety factors on ultimate and yield stresses, fracture limits (fracture control), fatigue lifetime, reuse criteria, operational criteria and procedures, stability factors, deflections, clearance, handling criteria, etc. The process is normally called a load cycle and is time consuming, very complex, and involves much more than structures. The key to successful structural design is the proper implementation of the process. It depends on many factors: leadership and management of the process, adequate analysis and testing tools, data basing, communications, people skills, and training. This process and the various factors involved are discussed.

Identifying Key Factors Relevant for Base Camp Siting

DTIC Science & Technology

2017-12-01

designated by other authorized documents. DESTROY THIS REPORT WHEN NO LONGER NEEDED. DO NOT RETURN IT TO THE ORIGINATOR. ERDC TR-17-17 iii Contents...Criteria Framework .......................................................................................... 6 3.1 Design templates...18 Tables Table 1. Design choice factors. Each

Calibration of Resistance Factors for Drilled Shafts for the New FHWA Design Method : Research Project Capsule

DOT National Transportation Integrated Search

2011-02-01

The Federal Highway Administration (FHWA) and American Association of State : Highway and Transportation Offi cials (AASHTO) require that all federally funded : bridges including substructures be designed using the load and resistance : factor design...

High-throughput spectrometer designs in a compact form-factor: principles and applications

NASA Astrophysics Data System (ADS)

Norton, S. M.

2013-05-01

Many compact, portable Raman spectrometers have entered the market in the past few years with applications in narcotics and hazardous material identification, as well as verification applications in pharmaceuticals and security screening. Often, the required compact form-factor has forced designers to sacrifice throughput and sensitivity for portability and low-cost. We will show that a volume phase holographic (VPH)-based spectrometer design can achieve superior throughput and thus sensitivity over conventional Czerny-Turner reflective designs. We will look in depth at the factors influencing throughput and sensitivity and illustrate specific VPH-based spectrometer examples that highlight these design principles.

Integrating ergonomics in design processes: a case study within an engineering consultancy firm.

PubMed

Sørensen, Lene Bjerg; Broberg, Ole

2012-01-01

This paper reports on a case study within an engineering consultancy firm, where engineering designers and ergonomists were working together on the design of a new hospital sterile processing plant. The objective of the paper is to gain a better understanding of the premises for integrating ergonomics into engineering design processes and how different factors either promote or limit the integration. Based on a grounded theory approach a model illustrating these factors is developed and different hypotheses about how these factors either promote and/or limit the integration of ergonomics into design processes is presented along with the model.

Factors that affect the fatigue strength of power transmission shafting and their impact on design

NASA Technical Reports Server (NTRS)

Leowenthal, S. H.

1986-01-01

A long standing objective in the design of power transmission shafting is to eliminate excess shaft material without compromising operational reliability. A shaft design method is presented which accounts for variable amplitude loading histories and their influence on limited life designs. The effects of combined bending and torsional loading are considered along with a number of application factors known to influence the fatigue strength of shafting materials. Among the factors examined are surface condition, size, stress concentration, residual stress and corrosion fatigue.

Human factors issues and approaches in the spatial layout of a space station control room, including the use of virtual reality as a design analysis tool

NASA Technical Reports Server (NTRS)

Hale, Joseph P., II

1994-01-01

Human Factors Engineering support was provided for the 30% design review of the late Space Station Freedom Payload Control Area (PCA). The PCA was to be the payload operations control room, analogous to the Spacelab Payload Operations Control Center (POCC). This effort began with a systematic collection and refinement of the relevant requirements driving the spatial layout of the consoles and PCA. This information was used as input for specialized human factors analytical tools and techniques in the design and design analysis activities. Design concepts and configuration options were developed and reviewed using sketches, 2-D Computer-Aided Design (CAD) drawings, and immersive Virtual Reality (VR) mockups.

Guidelines for the design and evaluation of human factors aspects of automated guideway transit systems

DOT National Transportation Integrated Search

1979-03-01

This report is a summary of human factors considerations for the planning, : deSign, construction, and implementation of Automated Guideway Transit (AGT) Systems : including Downtown People Mover (DPM) systems. Design concepts such as passenger : saf...

Hybrid PV/diesel solar power system design using multi-level factor analysis optimization

NASA Astrophysics Data System (ADS)

Drake, Joshua P.

Solar power systems represent a large area of interest across a spectrum of organizations at a global level. It was determined that a clear understanding of current state of the art software and design methods, as well as optimization methods, could be used to improve the design methodology. Solar power design literature was researched for an in depth understanding of solar power system design methods and algorithms. Multiple software packages for the design and optimization of solar power systems were analyzed for a critical understanding of their design workflow. In addition, several methods of optimization were studied, including brute force, Pareto analysis, Monte Carlo, linear and nonlinear programming, and multi-way factor analysis. Factor analysis was selected as the most efficient optimization method for engineering design as it applied to solar power system design. The solar power design algorithms, software work flow analysis, and factor analysis optimization were combined to develop a solar power system design optimization software package called FireDrake. This software was used for the design of multiple solar power systems in conjunction with an energy audit case study performed in seven Tibetan refugee camps located in Mainpat, India. A report of solar system designs for the camps, as well as a proposed schedule for future installations was generated. It was determined that there were several improvements that could be made to the state of the art in modern solar power system design, though the complexity of current applications is significant.

The study design elements employed by researchers in preclinical animal experiments from two research domains and implications for automation of systematic reviews.

PubMed

O'Connor, Annette M; Totton, Sarah C; Cullen, Jonah N; Ramezani, Mahmood; Kalivarapu, Vijay; Yuan, Chaohui; Gilbert, Stephen B

2018-01-01

Systematic reviews are increasingly using data from preclinical animal experiments in evidence networks. Further, there are ever-increasing efforts to automate aspects of the systematic review process. When assessing systematic bias and unit-of-analysis errors in preclinical experiments, it is critical to understand the study design elements employed by investigators. Such information can also inform prioritization of automation efforts that allow the identification of the most common issues. The aim of this study was to identify the design elements used by investigators in preclinical research in order to inform unique aspects of assessment of bias and error in preclinical research. Using 100 preclinical experiments each related to brain trauma and toxicology, we assessed design elements described by the investigators. We evaluated Methods and Materials sections of reports for descriptions of the following design elements: 1) use of comparison group, 2) unit of allocation of the interventions to study units, 3) arrangement of factors, 4) method of factor allocation to study units, 5) concealment of the factors during allocation and outcome assessment, 6) independence of study units, and 7) nature of factors. Many investigators reported using design elements that suggested the potential for unit-of-analysis errors, i.e., descriptions of repeated measurements of the outcome (94/200) and descriptions of potential for pseudo-replication (99/200). Use of complex factor arrangements was common, with 112 experiments using some form of factorial design (complete, incomplete or split-plot-like). In the toxicology dataset, 20 of the 100 experiments appeared to use a split-plot-like design, although no investigators used this term. The common use of repeated measures and factorial designs means understanding bias and error in preclinical experimental design might require greater expertise than simple parallel designs. Similarly, use of complex factor arrangements creates novel challenges for accurate automation of data extraction and bias and error assessment in preclinical experiments.

Smart home design and operation preferences of Americans and Koreans.

PubMed

Jeong, Kyeong-Ah; Salvendy, Gavriel; Proctor, Robert W

2010-05-01

The purpose of the present study was to generate both culture-specific and universal design and operational guidelines for smart homes. Questionnaire surveys were performed in the USA and South Korea to collect data on preferences for various aspects of the design and operation of smart homes. The factors that the survey participants considered most important were derived through factor analyses of the survey data and the responses of Americans and Koreans were compared to generate culture-specific guidelines. The five factors derived were: 1) environmental connection and control; 2) smart devices (appliances) and their control; 3) physical safety and security concerns; 4) comfort and relaxation issues; 5) control restriction issues. The two cultures showed different preference structures with statistical significance for all five factors. Prediction capability of the derived factors was also examined through multiple regressions for buying intention, interest, self-vision of living, moving intention, living satisfaction and perceived time and effort savings. 'Environmental connection and control' and 'smart devices (appliances) and their control' seemed to be the most influential factors for Americans and Koreans, respectively. STATEMENT OF RELEVANCE: Analysis of a survey of design and operational preferences for smart homes yielded five factors on which US and South Korean respondents differed. These factors form the basis for culture-specific guidelines, which, along with universal guidelines, should be followed in design of user-centred smart homes.

Factorial Design: An Eight Factor Experiment Using Paper Helicopters

NASA Technical Reports Server (NTRS)

Kozma, Michael

1996-01-01

The goal of this paper is to present the analysis of the multi-factor experiment (factorial design) conducted in EG490, Junior Design at Loyola College in Maryland. The discussion of this paper concludes the experimental analysis and ties the individual class papers together.

Human Factors Design Guide For Acquisition of Commercial-Off-The-Shelf Subsystems, Non-Developmental Items, and Developmental Systems

DOT National Transportation Integrated Search

1996-01-15

The Human Factors Design Guide (HFDG) provides reference information to assist : in the selection, analysis, design, development, and evaluation of new and m : odified Federal Aviation Administration (FAA) systems and equipment. A : preliminary editi...

Design of Experiments with Multiple Independent Variables: A Resource Management Perspective on Complete and Reduced Factorial Designs

PubMed Central

Collins, Linda M.; Dziak, John J.; Li, Runze

2009-01-01

An investigator who plans to conduct experiments with multiple independent variables must decide whether to use a complete or reduced factorial design. This article advocates a resource management perspective on making this decision, in which the investigator seeks a strategic balance between service to scientific objectives and economy. Considerations in making design decisions include whether research questions are framed as main effects or simple effects; whether and which effects are aliased (confounded) in a particular design; the number of experimental conditions that must be implemented in a particular design and the number of experimental subjects the design requires to maintain the desired level of statistical power; and the costs associated with implementing experimental conditions and obtaining experimental subjects. In this article four design options are compared: complete factorial, individual experiments, single factor, and fractional factorial designs. Complete and fractional factorial designs and single factor designs are generally more economical than conducting individual experiments on each factor. Although relatively unfamiliar to behavioral scientists, fractional factorial designs merit serious consideration because of their economy and versatility. PMID:19719358

What Informs Practice and What Is Valued in Corporate Instructional Design? A Mixed Methods Study

ERIC Educational Resources Information Center

Thompson-Sellers, Ingrid N.

2012-01-01

This study used a two-phased explanatory mixed-methods design to explore in-depth what factors are perceived by Instructional Design and Technology (IDT) professionals as impacting instructional design practice, how these factors are valued in the field, and what differences in perspectives exist between IDT managers and non-managers. For phase 1…

Design considerations for lunar base photovoltaic power systems

NASA Technical Reports Server (NTRS)

Hickman, J. Mark; Curtis, Henry B.; Landis, Geoffrey A.

1990-01-01

A survey was made of factors that may affect the design of photovoltaic arrays for a lunar base. These factors, which include the lunar environment and system design criteria, are examined. A photovoltaic power system design with a triangular array geometry is discussed and compared to a nuclear reactor power systems and a power system utilizing both nuclear and solar power sources.

Multi-Function Displays: A Guide for Human Factors Evaluation

DTIC Science & Technology

2013-11-01

mental workload in rotary wing aircraft . Ergonomics , 36, 1121 - 40. Smith, S., & Mosier, J. (1984). Design guidelines for the user interface for...Monterey Technologies, Inc., except one designated by (*), who is from CAMI. 16. Abstract This guide is designed to assist aircraft ...section. 17. Key Words 18. Distribution Statement Multi-Function Displays, Display Design , Avionics, Human Factors Criteria, Aircraft

Design Factors Affecting the Reaction Time for Identifying Toilet Signs: A Preliminary Study.

PubMed

Chen, Yi-Lang; Sie, Cai-Cin

2016-04-01

This study focused on the manner in which design factors affect the reaction time for identifying toilet signs. Taiwanese university students and staff members (50 men, 50 women; M age = 23.5 year, SD = 5.7) participated in the study. The 36 toilet signs were modified on three factors (six presenting styles, two figure-ground exchanges, and three colors), and the reaction time data of all participants were collected when the signs were presented in a simulation onscreen. Participants were quickest when reading Chinese text, followed by graphics and English texts. The findings also showed that men and women had different reaction times across various design combinations. These findings can serve as a reference for practically designing toilet signs, since design factors can lead to difficulties with comprehension based on reaction time measurements. © The Author(s) 2016.

Human Factors Society, Annual Meeting, 35th, San Francisco, CA, Sept. 2-6, 1991, Proceedings. Vols. 1 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

These proceedings discuss human factor issues related to aerospace systems, aging, communications, computer systems, consumer products, education and forensic topics, environmental design, industrial ergonomics, international technology transfer, organizational design and management, personality and individual differences in human performance, safety, system development, test and evaluation, training, and visual performance. Particular attention is given to HUDs, attitude indicators, and sensor displays; human factors of space exploration; behavior and aging; the design and evaluation of phone-based interfaces; knowledge acquisition and expert systems; handwriting, speech, and other input techniques; interface design for text, numerics, and speech; and human factor issues in medicine. Also discussedmore » are cumulative trauma disorders, industrial safety, evaluative techniques for automation impacts on the human operators, visual issues in training, and interpreting and organizing human factor concepts and information.« less

Human factors and the FDA's goals: improved medical device design.

PubMed

Burlington, D B

1996-01-01

The Food and Drug Administration's new human factors design requirements for medical devices were previewed by the director of the FDA's Center for Devices and Radiological Health (CDRH) at AAMI/FDA's Human Factors in Medical Devices Conference held in September 1995. Director Bruce Burlington, MD, said the FDA plans to take a closer look at how new medical devices are designed to ensure proper attention has been paid to human error prevention. As a medical practitioner who has witnessed use-related deaths and injuries, Burlington stressed the importance of the medical community's reporting use errors as they occur and manufacturers' creating easy-to-use labeling and packaging. He also called for simplicity and quality of design in medical products, and asked for a consolidated effort of all professionals involved in human factors issues to help implement and further the FDA's new human factors program. An edited version of his presentation appears here.

Preliminary Human Factors Guidelines for Automated Highway System Designers, Second Edition - Volume 2: User-System Transactions

DOT National Transportation Integrated Search

1998-04-01

Human factors can be defined as "designing to match the capabilities and limitations of the human user." The objectives of this human-centered design process are to maximize the effectiveness and efficiency of system performance, ensure a high level ...

Revitalising Assessment Design: What Is Holding New Lecturers Back?

ERIC Educational Resources Information Center

Norton, Lin; Norton, Bill; Shannon, Lee

2013-01-01

This paper reports on a survey study exploring new lecturers' views on assessment design (using a questionnaire called the Assessment Design Inventory) with 586 newly qualified or still qualifying lecturers from UK universities. A factor analysis established two factors labelled "desirable practice" and "constraints".…

Characterization and development of truck load spectra and growth factors for current and future pavement design practices in Louisiana.

DOT National Transportation Integrated Search

2011-07-01

For pavement design practices, several factors must be considered to ensure good pavement performance over the anticipated life cycle. : Such factors include, but are not limited to, the type of paving materials, traffic loading characteristics, prev...

Human Health/Human Factors Considerations in Trans-Lunar Space

NASA Technical Reports Server (NTRS)

Moore, E. Cherice; Howard, Robert; Mendeck, Gavin

2014-01-01

The human factors insights of how they are incorporated into the vehicle are crucial towards designing and planning the internal designs necessary for future spacecraft and missions. The adjusted mission concept of supporting the Asteroid Redirect Crewed Mission will drive some human factors changes on how the Orion will be used and will be reassessed so as to best contribute to missions success. Recognizing what the human factors and health functional needs are early in the design process and how to integrate them will improve this and future generations of space vehicles to achieve mission success and continue to minimize risks.

Design for human factors (DfHF): a grounded theory for integrating human factors into production design processes.

PubMed

Village, Judy; Searcy, Cory; Salustri, Filipo; Patrick Neumann, W

2015-01-01

The 'design for human factors' grounded theory explains 'how' human factors (HF) went from a reactive, after-injury programme in safety, to being proactively integrated into each step of the production design process. In this longitudinal case study collaboration with engineers and HF Specialists in a large electronics manufacturer, qualitative data (e.g. meetings, interviews, observations and reflections) were analysed using a grounded theory methodology. The central tenet in the theory is that when HF Specialists acclimated to the engineering process, language and tools, and strategically aligned HF to the design and business goals of the organisation, HF became a means to improve business performance. This led to engineers 'pulling' HF Specialists onto their team. HF targets were adopted into engineering tools to communicate HF concerns quantitatively, drive continuous improvement, visibly demonstrate change and lead to benchmarking. Senior management held engineers accountable for HF as a key performance indicator, thus integrating HF into the production design process. Practitioner Summary: Research and practice lack explanations about how HF can be integrated early in design of production systems. This three-year case study and the theory derived demonstrate how ergonomists changed their focus to align with design and business goals to integrate HF into the design process.

Designing Feature and Data Parallel Stochastic Coordinate Descent Method forMatrix and Tensor Factorization

DTIC Science & Technology

2016-05-11

AFRL-AFOSR-JP-TR-2016-0046 Designing Feature and Data Parallel Stochastic Coordinate Descent Method for Matrix and Tensor Factorization U Kang Korea...maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or   any other aspect...Designing Feature and Data Parallel Stochastic Coordinate Descent Method for Matrix and Tensor Factorization 5a.  CONTRACT NUMBER 5b.  GRANT NUMBER FA2386

Two-Stage Design Method for Enhanced Inductive Energy Transmission with Q-Constrained Planar Square Loops.

PubMed

Eteng, Akaa Agbaeze; Abdul Rahim, Sharul Kamal; Leow, Chee Yen; Chew, Beng Wah; Vandenbosch, Guy A E

2016-01-01

Q-factor constraints are usually imposed on conductor loops employed as proximity range High Frequency Radio Frequency Identification (HF-RFID) reader antennas to ensure adequate data bandwidth. However, pairing such low Q-factor loops in inductive energy transmission links restricts the link transmission performance. The contribution of this paper is to assess the improvement that is reached with a two-stage design method, concerning the transmission performance of a planar square loop relative to an initial design, without compromise to a Q-factor constraint. The first stage of the synthesis flow is analytical in approach, and determines the number and spacing of turns by which coupling between similar paired square loops can be enhanced with low deviation from the Q-factor limit presented by an initial design. The second stage applies full-wave electromagnetic simulations to determine more appropriate turn spacing and widths to match the Q-factor constraint, and achieve improved coupling relative to the initial design. Evaluating the design method in a test scenario yielded a more than 5% increase in link transmission efficiency, as well as an improvement in the link fractional bandwidth by more than 3%, without violating the loop Q-factor limit. These transmission performance enhancements are indicative of a potential for modifying proximity HF-RFID reader antennas for efficient inductive energy transfer and data telemetry links.

7 CFR 25.301 - Selection factors for designation of nominated rural areas.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 7 Agriculture 1 2012-01-01 2012-01-01 false Selection factors for designation of nominated rural areas. 25.301 Section 25.301 Agriculture Office of the Secretary of Agriculture RURAL EMPOWERMENT ZONES... rural areas. In choosing among nominated rural areas eligible for designation as Empowerment Zone...

7 CFR 25.301 - Selection factors for designation of nominated rural areas.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 1 2013-01-01 2013-01-01 false Selection factors for designation of nominated rural areas. 25.301 Section 25.301 Agriculture Office of the Secretary of Agriculture RURAL EMPOWERMENT ZONES... rural areas. In choosing among nominated rural areas eligible for designation as Empowerment Zone...

7 CFR 25.301 - Selection factors for designation of nominated rural areas.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 1 2014-01-01 2014-01-01 false Selection factors for designation of nominated rural areas. 25.301 Section 25.301 Agriculture Office of the Secretary of Agriculture RURAL EMPOWERMENT ZONES... rural areas. In choosing among nominated rural areas eligible for designation as Empowerment Zone...

7 CFR 25.301 - Selection factors for designation of nominated rural areas.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 1 2010-01-01 2010-01-01 false Selection factors for designation of nominated rural areas. 25.301 Section 25.301 Agriculture Office of the Secretary of Agriculture RURAL EMPOWERMENT ZONES... rural areas. In choosing among nominated rural areas eligible for designation as Empowerment Zone...

7 CFR 25.301 - Selection factors for designation of nominated rural areas.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 1 2011-01-01 2011-01-01 false Selection factors for designation of nominated rural areas. 25.301 Section 25.301 Agriculture Office of the Secretary of Agriculture RURAL EMPOWERMENT ZONES... rural areas. In choosing among nominated rural areas eligible for designation as Empowerment Zone...

Human factors design guide update (report number DOT/FAA/CT-96/01) : a revision to chapter 5--automation guidelines.

DOT National Transportation Integrated Search

2001-12-01

This document contains an updated and expanded version of the Automation chapter of the Human Factors Design Guide. A research : team of human factors experts evaluated the existing guidelines for relevance, clarity, and usability. The research team ...

Analysis and Design of Power Factor Pre-Regulator Based on a Symmetrical Charge Pump Circuit Applied to Electronic Ballast

NASA Astrophysics Data System (ADS)

Lazcano Olea, Miguel; Ramos Astudillo, Reynaldo; Sanhueza Robles, René; Rodriguez Rubke, Leopoldo; Ruiz-Caballero, Domingo Antonio

This paper presents the analysis and design of a power factor pre-regulator based on a symmetrical charge pump circuit applied to electronic ballast. The operation stages of the circuit are analyzed and its main design equations are obtained. Simulation and experimental results are presented in order to show the design methodology feasibility.

Investigation of structural factors of safety for the space shuttle

NASA Technical Reports Server (NTRS)

1972-01-01

A study was made of the factors governing the structural design of the fully reusable space shuttle booster to establish a rational approach to select optimum structural factors of safety. The study included trade studies of structural factors of safety versus booster service life, weight, cost, and reliability. Similar trade studies can be made on other vehicles using the procedures developed. The major structural components of a selected baseline booster were studied in depth, each being examined to determine the fatigue life, safe-life, and fail-safe capabilities of the baseline design. Each component was further examined to determine its reliability and safety requirements, and the change of structural weight with factors of safety. The apparent factors of safety resulting from fatigue, safe-life, proof test, and fail-safe requirements were identified. The feasibility of reduced factors of safety for design loads such as engine thrust, which are well defined, was examined.

Bio-Medical Factors and External Hazards in Space Station Design

NASA Technical Reports Server (NTRS)

Olling, Edward H.

1966-01-01

The design of space-station configurations is influenced by many factors, Probably the most demanding and critical are the biomedical and external hazards requirements imposed to provide the proper environment and supporting facilities for the crew and the adequate protective measures necessary to provide a configuration in which the crew can live and work efficiently in relative comfort and safety. The major biomedical factors, such as physiology, psychology, nutrition, personal hygiene, waste management, and recreation, all impose their own peculiar requirements. The commonality and integration of these requirements demand the utmost ingenuity and inventiveness be exercised in order to achieve effective configuration compliance. The relationship of biomedical factors for the internal space-station environment will be explored with respect to internal atmospheric constituency, atmospheric pressure levels, oxygen positive pressure, temperature, humidity, CO2 concentration, and atmospheric contamination. The range of these various parameters and the recommended levels for design use will be analyzed. Requirements and criteria for specific problem areas such as zero and artificial gravity and crew private quarters will be reviewed and the impact on the design of representative solutions will be presented. In the areas of external hazards, the impact of factors such as meteoroids, radiation, vacuum, temperature extremes, and cycling on station design will be evaluated. Considerations with respect to operational effectiveness and crew safety will be discussed. The impact of such factors on spacecraft design to achieve acceptable launch and reentry g levels, crew rotation intervals, etc., will be reviewed. Examples of configurations, subsystems, and internal a arrangement and installations to comply with such biomedical factor requirements will ber presented. The effects of solutions to certain biomedical factors on configuration weight, operational convenience, and program costs will be compared.

Human factors in spacecraft design

NASA Technical Reports Server (NTRS)

Harrison, Albert A.; Connors, Mary M.

1990-01-01

This paper describes some of the salient implications of evolving mission parameters for spacecraft design. Among the requirements for future spacecraft are new, higher standards of living, increased support of human productivity, and greater accommodation of physical and cultural variability. Design issues include volumetric allowances, architecture and layouts, closed life support systems, health maintenance systems, recreational facilities, automation, privacy, and decor. An understanding of behavioral responses to design elements is a precondition for critical design decisions. Human factors research results must be taken into account early in the course of the design process.

Factors that affect the fatigue strength of power transmission shafting

NASA Technical Reports Server (NTRS)

Loewenthal, S. H.

1984-01-01

A long standing objective in the design of power transmission shafting is to eliminate excess shaft material without compromising operational reliability. A shaft design method is presented which accounts for variable amplitude loading histories and their influence on limited life designs. The effects of combined bending and torsional loading are considered along with a number of application factors known to influence the fatigue strength of shafting materials. Among the factors examined are surface condition, size, stress concentration, residual stress and corrosion fatigue.

First-order reliability application and verification methods for semistatic structures

NASA Astrophysics Data System (ADS)

Verderaime, V.

1994-11-01

Escalating risks of aerostructures stimulated by increasing size, complexity, and cost should no longer be ignored in conventional deterministic safety design methods. The deterministic pass-fail concept is incompatible with probability and risk assessments; stress audits are shown to be arbitrary and incomplete, and the concept compromises the performance of high-strength materials. A reliability method is proposed that combines first-order reliability principles with deterministic design variables and conventional test techniques to surmount current deterministic stress design and audit deficiencies. Accumulative and propagation design uncertainty errors are defined and appropriately implemented into the classical safety-index expression. The application is reduced to solving for a design factor that satisfies the specified reliability and compensates for uncertainty errors, and then using this design factor as, and instead of, the conventional safety factor in stress analyses. The resulting method is consistent with current analytical skills and verification practices, the culture of most designers, and the development of semistatic structural designs.

Enhancing the Human Factors Engineering Role in an Austere Fiscal Environment

NASA Technical Reports Server (NTRS)

Stokes, Jack W.

2003-01-01

An austere fiscal environment in the aerospace community creates pressures to reduce program costs, often minimizing or sometimes even deleting the human interface requirements from the design process. With an assumption that the flight crew can recover real time from a poorly human factored space vehicle design, the classical crew interface requirements have been either not included in the design or not properly funded, though carried as requirements. Cost cuts have also affected quality of retained human factors engineering personnel. In response to this concern, planning is ongoing to correct the acting issues. Herein are techniques for ensuring that human interface requirements are integrated into a flight design, from proposal through verification and launch activation. This includes human factors requirements refinement and consolidation across flight programs; keyword phrases in the proposals; closer ties with systems engineering and other classical disciplines; early planning for crew-interface verification; and an Agency integrated human factors verification program, under the One NASA theme. Importance is given to communication within the aerospace human factors discipline, and utilizing the strengths of all government, industry, and academic human factors organizations in an unified research and engineering approach. A list of recommendations and concerns are provided in closing.

Enhancing healthcare process design with human factors engineering and reliability science, part 1: setting the context.

PubMed

Boston-Fleischhauer, Carol

2008-01-01

The design and implementation of efficient, effective, and safe processes are never-ending challenges in healthcare. Less than optimal performance levels and rising concerns about patient safety suggest that traditional process design methods are insufficient to meet design requirements. In this 2-part series, the author presents human factors engineering and reliability science as important knowledge to enhance existing operational and clinical process design methods in healthcare. An examination of these theories, application approaches, and examples are presented.

The Future Outlook for School Facilities Planning and Design.

ERIC Educational Resources Information Center

Brubaker, C. William

School design is influenced by four major factors: the education program, the community site, education technology, and building technology. Schools of the future are discussed in relation to the factors affecting school design. It is probable that future schools will be involved in a broader spectrum of programs and will serve a more diverse…

Hermes CX-7: Air transport system design simulation

NASA Technical Reports Server (NTRS)

Amer, Brian; Barter, John; Colucci, Jay; Foley, Caryn; Kockler, James; Rapp, David; Zeiger, Matthew

1992-01-01

The Hermes CX-7 has been designed to service the overnight parcel package delivery needs of the cities of Aeroworld as determined in the G-Dome Enterprises market survey. The design optimization centers on the prime goal of servicing the needs of these cities as efficiently and profitably as possible. The greatest factors which affect the design of an aircraft for the mission outlined in the Request for Proposal are cost, construction feasibility and effectiveness of the design. Other influencing factors are given by the constraints of the market, including a maximum takeoff and landing distance of 60 feet, storage capability in a container of size 5 ft. x 3 ft. x 2 ft., cargo packages of 2 inch and 4 inch cubes, and ability to turn with a radius no larger than 60 feet. Safety considerations such as flying at or below Mach one (30 ft/s) and controllability and maintainability of the aircraft must also be designed into the aircraft. Another influential factor is the efficiency of the aircraft which involves optimizations and tradeoffs of such factors as weight, lifting surface sizing, structural redundancy, and material costs.

Design evaluation in technology assessment: Illustrated by auditory impedance and sound distribution problems

NASA Technical Reports Server (NTRS)

Halldane, J. F.

1972-01-01

Technology is considered as a culture for changing a physical world and technology assessment questions the inherent cultural capability to modify power and material in support of living organisms. A comprehensive goal-parameter-synthesis-criterion specification is presented as a basis for a rational assessment of technology. The thesis queries the purpose of the assessed problems, the factors considered, the relationships between factors, and the values assigned those factors to accomplish the appropriate purpose. Stationary and sequential evaluation of enviro-organismic systems are delegated to the responsible personalities involved in design; from promoter/designer through contractor to occupant. Discussion includes design goals derived from organismic factors, definitions of human responses which establish viable criteria and relevant correlation models, linking stimulus parameters, and parallel problem-discipline centered design organization. A consistent concept of impedance, as a degradation in the performance of a specified parameter, is introduced to overcome the arbitrary inoperative connotations of terms like noise, discomfort, and glare. Applications of the evaluative specification are illustrated through design problems related to auditory impedance and sound distribution.

The influence of stem design on critical squeaking friction with ceramic bearings.

PubMed

Fan, Na; Morlock, Michael M; Bishop, Nicholas E; Huber, Gerd; Hoffmann, Norbert; Ciavarella, Michele; Chen, Guang X; Hothan, Arne; Witt, Florian

2013-10-01

Ceramic-on-ceramic hip joints have been reported to squeak, a phenomenon that may occur in compromised lubrication conditions. One factor related to the incidence of in vivo squeaking is the stem design. However, it has not yet been possible to relate stem design to squeaking in deteriorating lubrication conditions. The purpose of this study was to determine critical friction factors for different stem designs. A hip simulator was used to measure the friction factor of a ceramic bearing with different stem designs and gradually deteriorating lubrication represented by evaporation of a volatile fluid lubricant. The critical squeaking friction factor was measured at the onset of squeaking for each stem. Critical friction was higher for the long cobalt chrome (0.32 ± 0.02) and short titanium stems (0.39 ± 0.02) in comparison with a long titanium stem (0.29 ± 0.02). The onset of squeaking occurred at a friction factor lower than that measured for dry conditions, in which squeaking is usually investigated experimentally. The results suggest that shorter or heavier stems might limit the possibility of squeaking as lubrication deteriorates. The method developed can be used to investigate the influence of design parameters on squeaking probability. Copyright © 2013 Orthopaedic Research Society.

Sensitivity study on durability variables of marine concrete structures

NASA Astrophysics Data System (ADS)

Zhou, Xin'gang; Li, Kefei

2013-06-01

In order to study the influence of parameters on durability of marine concrete structures, the parameter's sensitivity analysis was studied in this paper. With the Fick's 2nd law of diffusion and the deterministic sensitivity analysis method (DSA), the sensitivity factors of apparent surface chloride content, apparent chloride diffusion coefficient and its time dependent attenuation factor were analyzed. The results of the analysis show that the impact of design variables on concrete durability was different. The values of sensitivity factor of chloride diffusion coefficient and its time dependent attenuation factor were higher than others. Relative less error in chloride diffusion coefficient and its time dependent attenuation coefficient induces a bigger error in concrete durability design and life prediction. According to probability sensitivity analysis (PSA), the influence of mean value and variance of concrete durability design variables on the durability failure probability was studied. The results of the study provide quantitative measures of the importance of concrete durability design and life prediction variables. It was concluded that the chloride diffusion coefficient and its time dependent attenuation factor have more influence on the reliability of marine concrete structural durability. In durability design and life prediction of marine concrete structures, it was very important to reduce the measure and statistic error of durability design variables.

Psychosocial Factors as Predictors of Mentoring among Nurses in Southwestern Nigeria

ERIC Educational Resources Information Center

Salami, Samuel O.

2008-01-01

Purpose: The purpose of this paper is to examine the psychosocial factors that predict mentoring among nurses. Design/methodology/approach: This study adopted a survey research design. Questionnaires were used to collect data on self-esteem, locus of control, emotional intelligence and demographic factors from 480 nurses (males 230; females = 250)…

[Impact of anchorage implant design factors on its primary stability].

PubMed

Zhang, J N; Lu, H P; Zhong, C

2017-08-09

During the past decade, the anchorage implants have been widely used in the orthodontic treatment. Many scholars have studied the influence of different factors on anchorage implant's primary stability, including anchorage implant's material properties, structural design, surgical procedure, bone condition, loading force's magnitude and direction. This article is to review the influence of anchorage implant's shape, dimension, neck design and thread design on its primary stability.

A Human Factors Evaluation of the Space Shuttle Cockpit Avionics Upgrade

DTIC Science & Technology

2012-09-01

cockpit design . This study assesses the CAU design employing human factors principles, evaluates baseline and CAU simulation data, and traces MW and SA...differences back to CAU design modifications. Significant improvements were found in all measures and across all conditions. These improvements were...found to be greater for ascent scenarios than for entry. From the findings, recommendations for the design and evaluation of future spacecraft

Human factors issues in the design of user interfaces for planning and scheduling

NASA Technical Reports Server (NTRS)

Murphy, Elizabeth D.

1991-01-01

The purpose is to provide and overview of human factors issues that impact the effectiveness of user interfaces to automated scheduling tools. The following methods are employed: (1) a survey of planning and scheduling tools; (2) the identification and analysis of human factors issues; (3) the development of design guidelines based on human factors literature; and (4) the generation of display concepts to illustrate guidelines.

Maximum projection designs for computer experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joseph, V. Roshan; Gul, Evren; Ba, Shan

Space-filling properties are important in designing computer experiments. The traditional maximin and minimax distance designs only consider space-filling in the full dimensional space. This can result in poor projections onto lower dimensional spaces, which is undesirable when only a few factors are active. Restricting maximin distance design to the class of Latin hypercubes can improve one-dimensional projections, but cannot guarantee good space-filling properties in larger subspaces. We propose designs that maximize space-filling properties on projections to all subsets of factors. We call our designs maximum projection designs. As a result, our design criterion can be computed at a cost nomore » more than a design criterion that ignores projection properties.« less

Maximum projection designs for computer experiments

DOE PAGES

Joseph, V. Roshan; Gul, Evren; Ba, Shan

2015-03-18

Space-filling properties are important in designing computer experiments. The traditional maximin and minimax distance designs only consider space-filling in the full dimensional space. This can result in poor projections onto lower dimensional spaces, which is undesirable when only a few factors are active. Restricting maximin distance design to the class of Latin hypercubes can improve one-dimensional projections, but cannot guarantee good space-filling properties in larger subspaces. We propose designs that maximize space-filling properties on projections to all subsets of factors. We call our designs maximum projection designs. As a result, our design criterion can be computed at a cost nomore » more than a design criterion that ignores projection properties.« less

Robust modular product family design

NASA Astrophysics Data System (ADS)

Jiang, Lan; Allada, Venkat

2001-10-01

This paper presents a modified Taguchi methodology to improve the robustness of modular product families against changes in customer requirements. The general research questions posed in this paper are: (1) How to effectively design a product family (PF) that is robust enough to accommodate future customer requirements. (2) How far into the future should designers look to design a robust product family? An example of a simplified vacuum product family is used to illustrate our methodology. In the example, customer requirements are selected as signal factors; future changes of customer requirements are selected as noise factors; an index called quality characteristic (QC) is set to evaluate the product vacuum family; and the module instance matrix (M) is selected as control factor. Initially a relation between the objective function (QC) and the control factor (M) is established, and then the feasible M space is systemically explored using a simplex method to determine the optimum M and the corresponding QC values. Next, various noise levels at different time points are introduced into the system. For each noise level, the optimal values of M and QC are computed and plotted on a QC-chart. The tunable time period of the control factor (the module matrix, M) is computed using the QC-chart. The tunable time period represents the maximum time for which a given control factor can be used to satisfy current and future customer needs. Finally, a robustness index is used to break up the tunable time period into suitable time periods that designers should consider while designing product families.

Factors impeding flexible inpatient unit design.

PubMed

Pati, Debajyoti; Evans, Jennie; Harvey, Thomas E; Bazuin, Doug

2012-01-01

To identify and examine factors extraneous to the design decision-making process that could impede the optimization of flexibility on inpatient units. A 2006 empirical study to identify domains of design decisions that affect flexibility on inpatient units found some indication in the context of the acuity-adaptable operational model that factors extraneous to the design process could have negatively influenced the successful implementation of the model. This raised questions regarding extraneous factors that might influence the successful optimization of flexibility. An exploratory, qualitative method was adopted to examine the question. Stakeholders from five recently built acute care inpatient units participated in the study, which involved three types of data collection: (1) verbal protocol data from a gaming session; (2) in-depth semi-structured interviews; and (3) shadowing frontline personnel. Data collection was conducted between June 2009 and November 2010. The study revealed at least nine factors extraneous to the design process that have the potential to hinder the optimization of flexibility in four domains: (1) systemic; (2) cultural; (3) human; and (4) financial. Flexibility is critical to hospital operations in the new healthcare climate, where cost reduction constitutes a vital target. From this perspective, flexibility and efficiency strategies can be influenced by (1) return on investment, (2) communication, (3) culture change, and (4) problem definition. Extraneous factors identified in this study could also affect flexibility in other care settings; therefore, these findings may be viewed from the overall context of hospital design.

Bio-Medical Factors and External Hazards in Space Station Design

NASA Technical Reports Server (NTRS)

Olling, E. H.

1966-01-01

The design of space-station configurations is influenced by many factors. Probably the most demanding and critical are the biomedical and external hazards requirements imposed to provide the proper environment and supporting facilities for the crew and the adequate protective measures necessary to provide a configuration'in which the crew can live and work efficiently in relative comfort and safety. The major biomedical factors, such as physiology, psychology, nutrition, personal hygiene, waste management, and recreation, all impose their own peculiar requirements. The commonality and integration of these requirements demand the utmost ingenuity and inventiveness be exercised in order to achieve effective configuration compliance. The relationship of biomedical factors for the internal space-station environment will be explored with respect to internal atmospheric constituency, atmospheric pressure levels, oxygen positive pressure, temperature, humidity, CO2 concentration, and atmospheric contamination. The range of these various parameters and the recommended levels for design use will be analyzed. Requirements and criteria for specific problem areas such as zero and artificial gravity and crew private quarters will be reviewed and the impact on the design of representative solutions will be presented. In the areas of external hazards, the impact of factors such as meteoroids, radiation, vacuum, temperature extremes, and cycling on station design will be evaluated. Considerations with respect to operational effectiveness and crew safety will be discussed. The impact of such factors on spacecraft design to achieve acceptable launch and reentry g levels, crew rotation intervals, etc., will be reviewed.

Design of 8-ft-Diameter Barrel Test Article Attachment Rings for Shell Buckling Knockdown Factor Project

NASA Technical Reports Server (NTRS)

Lovejoy, Andrew E.; Hilburger, Mark W.

2010-01-01

The Shell Buckling Knockdown Factor (SBKF) project includes the testing of sub-scale cylinders to validate new shell buckling knockdown factors for use in the design of the Ares-I and Ares-V launch vehicles. Test article cylinders represent various barrel segments of the Ares-I and Ares-V vehicles, and also include checkout test articles. Testing will be conducted at Marshall Space Flight Center (MSFC) for test articles having an eight-foot diameter outer mold line (OML) and having lengths that range from three to ten feet long. Both ends of the test articles will be connected to the test apparatus using attachment rings. Three multiple-piece and one single-piece design for the attachment rings were developed and analyzed. The single-piece design was chosen and will be fabricated from either steel or aluminum (Al) depending on the required safety factors (SF) for test hardware. This report summarizes the design and analysis of these attachment ring concepts.

Beyond Magnet® Designation: Perspectives From Nurse Managers on Factors of Sustainability and High-Performance Programming.

PubMed

Hayden, Margaret A; Wolf, Gail A; Zedreck-Gonzalez, Judith F

2016-10-01

The aim of this study was to identify patterns of high-performing behaviors and nurse manager perceptions of the factors of Magnet® sustainability at a multidesignated Magnet organization. The Magnet program recognizes exemplary professional nursing practice and is challenging to achieve and sustain. Only 10% (n = 42) of Magnet hospitals sustained designation for 12 years or longer. This study explored the perspectives of Magnet nurse managers regarding high-performing teams and the sustainability of Magnet designation. A qualitative study of nurse managers was conducted at 1 multidesignated Magnet organization (n = 13). Interview responses were analyzed using pattern recognition of Magnet model domains and characteristics of high-performing teams and then related to factors of Magnet sustainability. Transformational leadership is both an essential factor for sustainability and a potential barrier to sustainability of Magnet designation. Transformational nursing leaders lead high-performing teams and should be in place at all levels as an essential factor in sustaining Magnet redesignation.

The Study of the Relationship between Probabilistic Design and Axiomatic Design Methodology. Volume 2

NASA Technical Reports Server (NTRS)

Onwubiko, Chin-Yere; Onyebueke, Landon

1996-01-01

The structural design, or the design of machine elements, has been traditionally based on deterministic design methodology. The deterministic method considers all design parameters to be known with certainty. This methodology is, therefore, inadequate to design complex structures that are subjected to a variety of complex, severe loading conditions. A nonlinear behavior that is dependent on stress, stress rate, temperature, number of load cycles, and time is observed on all components subjected to complex conditions. These complex conditions introduce uncertainties; hence, the actual factor of safety margin remains unknown. In the deterministic methodology, the contingency of failure is discounted; hence, there is a use of a high factor of safety. It may be most useful in situations where the design structures are simple. The probabilistic method is concerned with the probability of non-failure performance of structures or machine elements. It is much more useful in situations where the design is characterized by complex geometry, possibility of catastrophic failure, sensitive loads and material properties. Also included: Comparative Study of the use of AGMA Geometry Factors and Probabilistic Design Methodology in the Design of Compact Spur Gear Set.

Effects of Buckling Knockdown Factor, Internal Pressure and Material on the Design of Stiffened Cylinders

NASA Technical Reports Server (NTRS)

Lovejoy, Andrew E.; Hilburger, Mark W.; Chunchu, Prasad B.

2010-01-01

A design study was conducted to investigate the effect shell buckling knockdown factor (SBKF), internal pressure and aluminum alloy material selection on the structural weight of stiffened cylindrical shells. Two structural optimization codes were used for the design study to determine the optimum minimum-weight design for a series of design cases, and included an in-house developed genetic algorithm (GA) code and PANDA2. Each design case specified a unique set of geometry, material, knockdown factor combinations and loads. The resulting designs were examined and compared to determine the effects of SBKF, internal pressure and material selection on the acreage design weight and controlling failure mode. This design study shows that use of less conservative SBKF values, including internal pressure, and proper selection of material alloy can result in significant weight savings for stiffened cylinders. In particular, buckling-critical cylinders with integrally machined stiffener construction can benefit from the use of thicker plate material that enables taller stiffeners, even when the stiffness, strength and density properties of these materials appear to be inferior.

Evaluation and optimization of hepatocyte culture media factors by design of experiments (DoE) methodology

PubMed Central

Dong, Jia; Lübberstedt, Marc; Urbaniak, Thomas; Nüssler, Andreas K.N.; Knobeloch, Daniel; Gerlach, Jörg C.; Zeilinger, Katrin

2008-01-01

Optimization of cell culture media based on statistical experimental design methodology is a widely used approach for improving cultivation conditions. We applied this methodology to refine the composition of an established culture medium for growth of a human hepatoma cell line, C3A. A selection of growth factors and nutrient supplements were systematically screened according to standard design of experiments (DoE) procedures. The results of the screening indicated that the medium additives hepatocyte growth factor, oncostatin M, and fibroblast growth factor 4 significantly influenced the metabolic activities of the C3A cell line. Surface response methodology revealed that the optimum levels for these factors were 30 ng/ml for hepatocyte growth factor and 35 ng/ml for oncostatin M. Additional experiments on primary human hepatocyte cultures showed high variance in metabolic activities between cells from different individuals, making determination of optimal levels of factors more difficult. Still, it was possible to conclude that hepatocyte growth factor, epidermal growth factor, and oncostatin M had decisive effects on the metabolic functions of primary human hepatocytes. PMID:19003182

Evaluation and optimization of hepatocyte culture media factors by design of experiments (DoE) methodology.

PubMed

Dong, Jia; Mandenius, Carl-Fredrik; Lübberstedt, Marc; Urbaniak, Thomas; Nüssler, Andreas K N; Knobeloch, Daniel; Gerlach, Jörg C; Zeilinger, Katrin

2008-07-01

Optimization of cell culture media based on statistical experimental design methodology is a widely used approach for improving cultivation conditions. We applied this methodology to refine the composition of an established culture medium for growth of a human hepatoma cell line, C3A. A selection of growth factors and nutrient supplements were systematically screened according to standard design of experiments (DoE) procedures. The results of the screening indicated that the medium additives hepatocyte growth factor, oncostatin M, and fibroblast growth factor 4 significantly influenced the metabolic activities of the C3A cell line. Surface response methodology revealed that the optimum levels for these factors were 30 ng/ml for hepatocyte growth factor and 35 ng/ml for oncostatin M. Additional experiments on primary human hepatocyte cultures showed high variance in metabolic activities between cells from different individuals, making determination of optimal levels of factors more difficult. Still, it was possible to conclude that hepatocyte growth factor, epidermal growth factor, and oncostatin M had decisive effects on the metabolic functions of primary human hepatocytes.

Controlled Release Strategies for Bone, Cartilage, and Osteochondral Engineering—Part I: Recapitulation of Native Tissue Healing and Variables for the Design of Delivery Systems

PubMed Central

Santo, Vítor E.; Mano, João F.; Reis, Rui L.

2013-01-01

The potential of growth factors to stimulate tissue healing through the enhancement of cell proliferation, migration, and differentiation is undeniable. However, critical parameters on the design of adequate carriers, such as uncontrolled spatiotemporal presence of bioactive factors, inadequate release profiles, and supraphysiological dosages of growth factors, have impaired the translation of these systems onto clinical practice. This review describes the healing cascades for bone, cartilage, and osteochondral interface, highlighting the role of specific growth factors for triggering the reactions leading to tissue regeneration. Critical criteria on the design of carriers for controlled release of bioactive factors are also reported, focusing on the need to provide a spatiotemporal control over the delivery and presentation of these molecules. PMID:23268651

Considerations for the design of safe and effective consumer health IT applications in the home.

PubMed

Zayas-Cabán, Teresa; Dixon, Brian E

2010-10-01

Consumer health IT applications have the potential to improve quality, safety and efficiency of consumers' interactions with the healthcare system. Yet little attention has been paid to human factors and ergonomics in the design of consumer health IT, potentially limiting the ability of health IT to achieve these goals. This paper presents the results of an analysis of human factors and ergonomics issues encountered by five projects during the design and implementation of home-based consumer health IT applications. Agency for Healthcare Research and Quality-funded consumer health IT research projects, where patients used the IT applications in their homes, were reviewed. Project documents and discussions with project teams were analysed to identify human factors and ergonomic issues considered or addressed by project teams. The analysis focused on system design and design processes used as well as training, implementation and use of the IT intervention. A broad range of consumer health IT applications and diverse set of human factors and ergonomics issues were identified. The design and implementation processes used resulted in poor fit with some patients' healthcare tasks and the home environment and, in some cases, resulted in lack of use. Clinician interaction with patients and the information provided through health IT applications appeared to positively influence adoption and use. Consumer health IT application design would benefit from the use of human factors and ergonomics design and evaluation methods. Considering the context in which home-based consumer health IT applications are used will likely affect the ability of these applications to positively impact the quality, safety and efficiency of patient care.

Teaching fractional factorial experiments via course delegate designed experiments.

PubMed

Coleman, S; Antony, J

1999-01-01

Industrial experiments are fundamental in enhancing the understanding and knowledge of a process and product behavior. Designed industrial experiments assist people in understanding, investigating, and improving their processes. The purpose of a designed experiment is to understand which factors might influence the process output and then to determine those factor settings that optimize the process output. Teaching "design of experiments" using textbook examples does not fully shed light on how to identify and formulate the problem, identify factors, and determine the performance of the physical experiment. Presented here is an example of how to teach fractional factorial experiments in a course on designed experiments. Also presented is a practical, hands-on experiment that has been found to be extremely successful in instilling confidence and motivation in course delegates. The experiment provides a great stimulus to the delegates for the application of experimental design in their own work environment.

First Order Reliability Application and Verification Methods for Semistatic Structures

NASA Technical Reports Server (NTRS)

Verderaime, Vincent

1994-01-01

Escalating risks of aerostructures stimulated by increasing size, complexity, and cost should no longer be ignored by conventional deterministic safety design methods. The deterministic pass-fail concept is incompatible with probability and risk assessments, its stress audits are shown to be arbitrary and incomplete, and it compromises high strength materials performance. A reliability method is proposed which combines first order reliability principles with deterministic design variables and conventional test technique to surmount current deterministic stress design and audit deficiencies. Accumulative and propagation design uncertainty errors are defined and appropriately implemented into the classical safety index expression. The application is reduced to solving for a factor that satisfies the specified reliability and compensates for uncertainty errors, and then using this factor as, and instead of, the conventional safety factor in stress analyses. The resulting method is consistent with current analytical skills and verification practices, the culture of most designers, and with the pace of semistatic structural designs.

A Method for the Constrained Design of Natural Laminar Flow Airfoils

NASA Technical Reports Server (NTRS)

Green, Bradford E.; Whitesides, John L.; Campbell, Richard L.; Mineck, Raymond E.

1996-01-01

A fully automated iterative design method has been developed by which an airfoil with a substantial amount of natural laminar flow can be designed, while maintaining other aerodynamic and geometric constraints. Drag reductions have been realized using the design method over a range of Mach numbers, Reynolds numbers and airfoil thicknesses. The thrusts of the method are its ability to calculate a target N-Factor distribution that forces the flow to undergo transition at the desired location; the target-pressure-N-Factor relationship that is used to reduce the N-Factors in order to prolong transition; and its ability to design airfoils to meet lift, pitching moment, thickness and leading-edge radius constraints while also being able to meet the natural laminar flow constraint. The method uses several existing CFD codes and can design a new airfoil in only a few days using a Silicon Graphics IRIS workstation.

Estimation of sample size and testing power (part 6).

PubMed

Hu, Liang-ping; Bao, Xiao-lei; Guan, Xue; Zhou, Shi-guo

2012-03-01

The design of one factor with k levels (k ≥ 3) refers to the research that only involves one experimental factor with k levels (k ≥ 3), and there is no arrangement for other important non-experimental factors. This paper introduces the estimation of sample size and testing power for quantitative data and qualitative data having a binary response variable with the design of one factor with k levels (k ≥ 3).

Owens Community College: A Case Study on the Effects of Politics, Economics, Social Factors, and Technological Factors on Future Educational Delivery Strategies, Space Needs, and Design

ERIC Educational Resources Information Center

Paskvan, Brian A.

2011-01-01

The purpose of this case study was to explore the influence of four factors--politics, economics, society, and technology--on educational delivery strategies, space needs, and design at Owens Community College. The future effects of these factors on the college were predicted four to six years from the time the study was conducted. The researcher…

A survey of scientific literacy to provide a foundation for designing science communication in Japan.

PubMed

Kawamoto, Shishin; Nakayama, Minoru; Saijo, Miki

2013-08-01

There are various definitions and survey methods for scientific literacy. Taking into consideration the contemporary significance of scientific literacy, we have defined it with an emphasis on its social aspects. To acquire the insights needed to design a form of science communication that will enhance the scientific literacy of each individual, we conducted a large-scale random survey within Japan of individuals older than 18 years, using a printed questionnaire. The data thus acquired were analyzed using factor analysis and cluster analysis to create a 3-factor/4-cluster model of people's interest and attitude toward science, technology and society and their resulting tendencies. Differences were found among the four clusters in terms of the three factors: scientific factor, social factor, and science-appreciating factor. We propose a plan for designing a form of science communication that is appropriate to this current status of scientific literacy in Japan.

Automating a human factors evaluation of graphical user interfaces for NASA applications: An update on CHIMES

NASA Technical Reports Server (NTRS)

Jiang, Jian-Ping; Murphy, Elizabeth D.; Bailin, Sidney C.; Truszkowski, Walter F.

1993-01-01

Capturing human factors knowledge about the design of graphical user interfaces (GUI's) and applying this knowledge on-line are the primary objectives of the Computer-Human Interaction Models (CHIMES) project. The current CHIMES prototype is designed to check a GUI's compliance with industry-standard guidelines, general human factors guidelines, and human factors recommendations on color usage. Following the evaluation, CHIMES presents human factors feedback and advice to the GUI designer. The paper describes the approach to modeling human factors guidelines, the system architecture, a new method developed to convert quantitative RGB primaries into qualitative color representations, and the potential for integrating CHIMES with user interface management systems (UIMS). Both the conceptual approach and its implementation are discussed. This paper updates the presentation on CHIMES at the first International Symposium on Ground Data Systems for Spacecraft Control.

Dimensions of Culturally Sensitive Factors in the Design and Development of Learning Objects

ERIC Educational Resources Information Center

Qi, Mei; Boyle, Tom

2010-01-01

Open educational resources (OERs) are designed to be globally reusable. Yet comparatively little attention has been given to the cultural issues. This paper addresses the issue of culturally sensitive factors that may influence the design of reusable learning objects. These influences are often subtle and hard to manage. The paper proposes a…

Transforming Interaction and Social Presence through Course Design: Authentic Implementation of Threaded Discussion Tools

ERIC Educational Resources Information Center

Pierce, Richard

2013-01-01

This study investigated course design factors influencing social presence and the development of ICT self-efficacy. Instructional design factors that promoted authentic uses of threaded discussions as a vehicle to establish social presence, self-directed learning and cooperative learning resulted in 900 posts in a semester, when no posts were…

DESIGN GUIDELINES FOR GOOD HEARING CONDITIONS AND EFFECTIVE NOISE CONTROL IN SCHOOL CLASSROOMS.

ERIC Educational Resources Information Center

KINGSBURY, H.F.; TAYLOR, D.W.

TWO OF THE MOST IMPORTANT OPERATIVE DESIGN FACTORS GOVERNING SPEECH PERCEPTION IN CLASSROOMS HAVE BEEN EXAMINED AND GUIDELINES IN THE FORM OF GRAPHS, ETC. CONSTRUCTED THAT SHOULD BE UNDERSTANDABLE TO AND USABLE BY THOSE ASSOCIATED WITH SCHOOL PLANNING AND DESIGN. THE TWO FACTORS CONSIDERED ARE--(1) PROVISION FOR OPTIMUM REVERBERATION TIME, AND (2)…

HERE'S HOW TO DESIGN A SCHOOL CAFETERIA.

ERIC Educational Resources Information Center

POWERS, ALICE

A DISCUSSION IS PRESENTED OF THE FACTORS INVOLVED IN DESIGNING A SYSTEM OF "UNIT KITCHENS." REASONS FOR CHOICE OF A UNIT SYSTEM OVER A CENTRAL KITCHEN ARE GIVEN, AND A DETAILED ANALYSIS OF THE FACTORS INVOLVED IN DESIGNING AND EQUIPPING SUCH FACILITIES IS PRESENTED. THIS ARTICLE APPEARED IN THE NOVEMBER-DECEMBER 1964 ISSUE OF THE SCHOOL LUNCH…

Space Human Factors: Research to Application

NASA Technical Reports Server (NTRS)

Woolford, Barbara

2008-01-01

Human Factors has been instrumental in preventing potential on-orbit hazards and increasing overall crew safety. Poor performance & operational learning curves on-orbit are mitigated. Human-centered design is applied to optimize design and minimize potentially hazardous conditions, especially with larger crew sizes and habitat constraints. Lunar and Mars requirements and design developments are enhanced, based on ISS Lessons Learned.

Manufacturing and Cost Considerations in Multidisciplinary Aircraft Design (Research on Mathematical Modeling of Manufacturability Factors)

NASA Technical Reports Server (NTRS)

Rais-Rohani, Masoud

1996-01-01

The identification of airframe Manufacturability Factors/Cost Drivers (MFCD) and the method by which the relationships between MFCD and designer-controlled parameters could be properly modeled are described.

Impact of Study Design on Reported Incidences of Acute Mountain Sickness: A Systematic Review.

PubMed

Waeber, Baptiste; Kayser, Bengt; Dumont, Lionel; Lysakowski, Christopher; Tramèr, Martin R; Elia, Nadia

2015-09-01

Published incidences of acute mountain sickness (AMS) vary widely. Reasons for this variation, and predictive factors of AMS, are not well understood. We aimed to identify predictive factors that are associated with the occurrence of AMS, and to test the hypothesis that study design is an independent predictive factor of AMS incidence. We did a systematic search (Medline, bibliographies) for relevant articles in English or French, up to April 28, 2013. Studies of any design reporting on AMS incidence in humans without prophylaxis were selected. Data on incidence and potential predictive factors were extracted by two reviewers and crosschecked by four reviewers. Associations between predictive factors and AMS incidence were sought through bivariate and multivariate analyses for different study designs separately. Association between AMS incidence and study design was assessed using multiple linear regression. We extracted data from 53,603 subjects from 34 randomized controlled trials, 44 cohort studies, and 33 cross-sectional studies. In randomized trials, the median of AMS incidences without prophylaxis was 60% (range, 16%-100%); mode of ascent and population were significantly associated with AMS incidence. In cohort studies, the median of AMS incidences was 51% (0%-100%); geographical location was significantly associated with AMS incidence. In cross-sectional studies, the median of AMS incidences was 32% (0%-68%); mode of ascent and maximum altitude were significantly associated with AMS incidence. In a multivariate analysis, study design (p=0.012), mode of ascent (p=0.003), maximum altitude (p<0.001), population (p=0.002), and geographical location (p<0.001) were significantly associated with AMS incidence. Age, sex, speed of ascent, duration of exposure, or history of AMS were inconsistently reported and therefore not further analyzed. Reported incidences and identifiable predictive factors of AMS depend on study design.

Review: Factors affecting fouling in conventional pens for slaughter pigs.

PubMed

Larsen, M L V; Bertelsen, M; Pedersen, L J

2018-02-01

This review assesses factors affecting fouling in conventional pens for slaughter pigs. Fouling of the pen happens when pigs change their excretory behaviour from occurring in the designated dunging area to the lying area. This can result in a lower hygiene, bad air quality, extra work for the farmer, disturbance of the pigs' resting behaviour and an increase in agonistic interactions. A systematic search was conducted and results narrowed down to 21 articles. Four factors were found to affect fouling directly: insufficient space allowance, the flooring design of the pen, the thermal climate and pigs' earlier experience. Further, these primary factors are affected by secondary factors such as the shape of the pen, the weight of the pigs and especially the heat balance of the pigs, which is affected by several tertiary factors including, for example, temperature, humidity and draught. Results indicate that the most important factor to control when trying to prevent fouling of a pen is the pen climate. An appropriate climate may be accomplished through floor cooling in the designated lying area, sprinklers above the designated dunging area and by ensuring a more optimal ambient temperature curve that also fits the weight of the pigs in different stages of the production. All in all, fouling of the pen in conventional slaughter pigs is a multifactorial problem, but it is important to focus on increasing the comfortability, and especially the climate, of the designated lying area.

Results of Education Program of “Training of Designers for Town Renovation”

NASA Astrophysics Data System (ADS)

Nitta, Yasutsugu; Inoi, Hiroto

The paper introduces the outline and results of the education program of “Training of designers for town renovation”, which has been done for two years in Osaka University, sponsored by the Ministry of education, culture, sports, science and technology. The program has three main aims as follows ; to understand three factors of town planning, “Shape”, “System” and “Mind” and master the design skills for realizing three factors, to master the design skills integrating three factors which are “Environment”, “Social” and “Economic”, and to perceive various people living, improve the ability of communicating and enhance the desire of participating town planning process.

Best practices of Building Information Modelling (BIM) implementation in design phase for construction project

NASA Astrophysics Data System (ADS)

Kasim, N.; Zainal Abidin, N. A.; Zainal, R.; Sarpin, N.; Rahim, M. H. I. Abd; Saikah, M.

2017-11-01

Implementation of Building Information Modelling (BIM) was expected to bring improvement in current practices of Malaysian construction industry. In the design phase, there is a lack of a ready pool of skilled workers who are able to develop BIM strategic plan and effectively utilise it. These create boundaries for BIM nature in Malaysian construction industry specifically in the design phase to achieve its best practices. Therefore, the objectives of this research are to investigate the current practices of BIM implementation in the design phase as well as the best practices factors of BIM implementation in the design phase. The qualitative research approach is carried out through semi-structured interviews with the designers of different organisations which adopt BIM in the design phase. Data collection is analysed by executing content analysis method. From the findings, the best practices factors of BIM implementation in design phase such as the incentive for BIM training, formal approach to monitoring automated Level of Detailing (LOD), run a virtual meeting and improve Industry Foundation Class (IFC). Thus, best practices factors which lead to practices improvements in the design phase of project development which subsequently improves the implementation of BIM in the design phase of Malaysian construction industry.

Air and Space Operations Center (AOC) Facility Design Guidelines: A Human Factors Engineering Perspective

DTIC Science & Technology

2006-07-01

31 July 1995 3. Human Engineering Guide to Equipment Design, Department of Defense, Washington D.C., 1972 4. American National Standard for Human Factors Engineering of Visual Display Terminal Workstations , ANSI

Buckling Design and Imperfection Sensitivity of Sandwich Composite Launch-Vehicle Shell Structures

NASA Technical Reports Server (NTRS)

Schultz, Marc R.; Sleight, David W.; Myers, David E.; Waters, W. Allen, Jr.; Chunchu, Prasad B.; Lovejoy, Andrew W.; Hilburger, Mark W.

2016-01-01

Composite materials are increasingly being considered and used for launch-vehicle structures. For shell structures, such as interstages, skirts, and shrouds, honeycomb-core sandwich composites are often selected for their structural efficiency. Therefore, it is becoming increasingly important to understand the structural response, including buckling, of sandwich composite shell structures. Additionally, small geometric imperfections can significantly influence the buckling response, including considerably reducing the buckling load, of shell structures. Thus, both the response of the theoretically perfect structure and the buckling imperfection sensitivity must be considered during the design of such structures. To address the latter, empirically derived design factors, called buckling knockdown factors (KDFs), were developed by NASA in the 1960s to account for this buckling imperfection sensitivity during design. However, most of the test-article designs used in the development of these recommendations are not relevant to modern launch-vehicle constructions and material systems, and in particular, no composite test articles were considered. Herein, a two-part study on composite sandwich shells to (1) examine the relationship between the buckling knockdown factor and the areal mass of optimized designs, and (2) to interrogate the imperfection sensitivity of those optimized designs is presented. Four structures from recent NASA launch-vehicle development activities are considered. First, designs optimized for both strength and stability were generated for each of these structures using design optimization software and a range of buckling knockdown factors; it was found that the designed areal masses varied by between 6.1% and 19.6% over knockdown factors ranging from 0.6 to 0.9. Next, the buckling imperfection sensitivity of the optimized designs is explored using nonlinear finite-element analysis and the as-measured shape of a large-scale composite cylindrical shell. When compared with the current buckling design recommendations, the results suggest that the current recommendations are overly conservative and that the development of new recommendations could reduce the acreage areal mass of many composite sandwich shell designs by between 4% and 19%, depending on the structure.

Human factors certification in the development of future air traffic control systems

NASA Technical Reports Server (NTRS)

Evans, Alyson E.

1994-01-01

If human factors certification of aviation technologies aims to encompass the wide range of issues which need to be addressed for any new system, then human factors involvement must be present throughout the whole design process in a manner which relates to final certification. A certification process cannot simply be applied to the final product of design. Standards and guidelines will be required by designers at the outset of design for reference in preparing for certification. The most effective use of human factors principles, methods, and measures is made as part of an iterative design process, leading to a system which reflects these as far as possible. This particularly applies where the technology is complex and may be represented by a number of components or sub-systems. Some aspects of the system are best certified during early prototyping, when there is still scope to make changes to software or hardware. At this stage in design, financial and/or time pressures will not rule out the possibility of necessary changes, as may be the case later. Other aspects of the system will be best certified during the final phases of design when the system is in a more complete form and in a realistic environment.

Ontogenetic changes in size, allometry, and mechanical design of tropical rain forest trees.

PubMed

Sterck, F; Bongers, F

1998-02-01

Size, allometry, and mechanical design were measured for trees of three canopy species in a tropical rain forest in French Guiana. Mechanical design was expressed as the safety factor, using the elastic-stability model, and the wind resistance factor, using the constant-stress model. Changes with ontogeny were described as regressions using stem diameter as the independent variable, and they were compared between species. Height, crown size, and the wind resistance factor increased with ontogeny. The safety factor decreased to a minimum and then increased continuously in thicker trees. The crown width/height ratio did not change with ontogeny. Interspecific differences in allometry and mechanical design were related to the adult stature of the species, and not to shade tolerance. The short stature species (Vouacapoua americana) was less slender (height:DBH [stem diameter at 1.3 m] ratio) and had a higher crown width/height ratio than the tall stature species (Goupia glabra and Dicorynia guianensis). Vouacapoua had a higher safety factor, but a similar wind resistance factor. The safety factors of our study species were lower than those of two temperate tree species because of a higher slenderness. Differences in safety factors between tropical and temperate trees may result from unrealistic assumptions of the elastic-stability model, and may also be related to lower light levels and-or wind rates in the tropics.

Design of a transverse-flux permanent-magnet linear generator and controller for use with a free-piston stirling engine

NASA Astrophysics Data System (ADS)

Zheng, Jigui; Huang, Yuping; Wu, Hongxing; Zheng, Ping

2016-07-01

Transverse-flux with high efficiency has been applied in Stirling engine and permanent magnet synchronous linear generator system, however it is restricted for large application because of low and complex process. A novel type of cylindrical, non-overlapping, transverse-flux, and permanent-magnet linear motor(TFPLM) is investigated, furthermore, a high power factor and less process complexity structure research is developed. The impact of magnetic leakage factor on power factor is discussed, by using the Finite Element Analysis(FEA) model of stirling engine and TFPLM, an optimization method for electro-magnetic design of TFPLM is proposed based on magnetic leakage factor. The relation between power factor and structure parameter is investigated, and a structure parameter optimization method is proposed taking power factor maximum as a goal. At last, the test bench is founded, starting experimental and generating experimental are performed, and a good agreement of simulation and experimental is achieved. The power factor is improved and the process complexity is decreased. This research provides the instruction to design high-power factor permanent-magnet linear generator.

An Analysis of Factors that Inhibit Business Use of User-Centered Design Principles: A Delphi Study

ERIC Educational Resources Information Center

Hilton, Tod M.

2010-01-01

The use of user-centered design (UCD) principles has a positive impact on the use of web-based interactive systems in customer-centric organizations. User-centered design methodologies are not widely adopted in organizations due to intraorganizational factors. A qualitative study using a modified Delphi technique was used to identify the factors…

49 CFR 192.111 - Design factor (F) for steel pipe.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 3 2012-10-01 2012-10-01 false Design factor (F) for steel pipe. 192.111 Section...) for steel pipe. (a) Except as otherwise provided in paragraphs (b), (c), and (d) of this section, the... less must be used in the design formula in § 192.105 for steel pipe in Class 1 locations that: (1...

49 CFR 192.111 - Design factor (F) for steel pipe.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 3 2013-10-01 2013-10-01 false Design factor (F) for steel pipe. 192.111 Section...) for steel pipe. (a) Except as otherwise provided in paragraphs (b), (c), and (d) of this section, the... less must be used in the design formula in § 192.105 for steel pipe in Class 1 locations that: (1...

49 CFR 192.111 - Design factor (F) for steel pipe.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 3 2014-10-01 2014-10-01 false Design factor (F) for steel pipe. 192.111 Section...) for steel pipe. (a) Except as otherwise provided in paragraphs (b), (c), and (d) of this section, the... less must be used in the design formula in § 192.105 for steel pipe in Class 1 locations that: (1...

49 CFR 192.111 - Design factor (F) for steel pipe.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Design factor (F) for steel pipe. 192.111 Section...) for steel pipe. (a) Except as otherwise provided in paragraphs (b), (c), and (d) of this section, the... less must be used in the design formula in § 192.105 for steel pipe in Class 1 locations that: (1...

Team-Centered Perspective for Adaptive Automation Design

NASA Technical Reports Server (NTRS)

Prinzel, Lawrence J., III

2003-01-01

Automation represents a very active area of human factors research. The journal, Human Factors, published a special issue on automation in 1985. Since then, hundreds of scientific studies have been published examining the nature of automation and its interaction with human performance. However, despite a dramatic increase in research investigating human factors issues in aviation automation, there remain areas that need further exploration. This NASA Technical Memorandum describes a new area of automation design and research, called adaptive automation. It discusses the concepts and outlines the human factors issues associated with the new method of adaptive function allocation. The primary focus is on human-centered design, and specifically on ensuring that adaptive automation is from a team-centered perspective. The document shows that adaptive automation has many human factors issues common to traditional automation design. Much like the introduction of other new technologies and paradigm shifts, adaptive automation presents an opportunity to remediate current problems but poses new ones for human-automation interaction in aerospace operations. The review here is intended to communicate the philosophical perspective and direction of adaptive automation research conducted under the Aerospace Operations Systems (AOS), Physiological and Psychological Stressors and Factors (PPSF) project.

Optimization of the Ion Source-Mass Spectrometry Parameters in Non-Steroidal Anti-Inflammatory and Analgesic Pharmaceuticals Analysis by a Design of Experiments Approach

NASA Astrophysics Data System (ADS)

Paíga, Paula; Silva, Luís M. S.; Delerue-Matos, Cristina

2016-10-01

The flow rates of drying and nebulizing gas, heat block and desolvation line temperatures and interface voltage are potential electrospray ionization parameters as they may enhance sensitivity of the mass spectrometer. The conditions that give higher sensitivity of 13 pharmaceuticals were explored. First, Plackett-Burman design was implemented to screen significant factors, and it was concluded that interface voltage and nebulizing gas flow were the only factors that influence the intensity signal for all pharmaceuticals. This fractionated factorial design was projected to set a full 22 factorial design with center points. The lack-of-fit test proved to be significant. Then, a central composite face-centered design was conducted. Finally, a stepwise multiple linear regression and subsequently an optimization problem solving were carried out. Two main drug clusters were found concerning the signal intensities of all runs of the augmented factorial design. p-Aminophenol, salicylic acid, and nimesulide constitute one cluster as a result of showing much higher sensitivity than the remaining drugs. The other cluster is more homogeneous with some sub-clusters comprising one pharmaceutical and its respective metabolite. It was observed that instrumental signal increased when both significant factors increased with maximum signal occurring when both codified factors are set at level +1. It was also found that, for most of the pharmaceuticals, interface voltage influences the intensity of the instrument more than the nebulizing gas flowrate. The only exceptions refer to nimesulide where the relative importance of the factors is reversed and still salicylic acid where both factors equally influence the instrumental signal.

Best Bang for the Buck: Part 2 – Choosing Between Different Sized Designs

DOE PAGES

Anderson-Cook, Christine Michaela; Lu, Lu

2016-11-01

Last month, we considered four potential designs of varying sizes and a variety of their attributes for an engineering problem involving a screening design with seven factors. The engineer’s original request was to find a design with 14 runs that could estimate all of the main effects, as well as have some potential for finding important two-factor interactions and possibly curvature in the underlying surface. This assessment was that the proposed size of design was potentially a bit too ambitious for the experiment’s goals, so we explored three other competing designs that had slightly larger sizes but were able tomore » improve several aspects of the design.« less

Best Bang for the Buck: Part 2 – Choosing Between Different Sized Designs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson-Cook, Christine Michaela; Lu, Lu

Last month, we considered four potential designs of varying sizes and a variety of their attributes for an engineering problem involving a screening design with seven factors. The engineer’s original request was to find a design with 14 runs that could estimate all of the main effects, as well as have some potential for finding important two-factor interactions and possibly curvature in the underlying surface. This assessment was that the proposed size of design was potentially a bit too ambitious for the experiment’s goals, so we explored three other competing designs that had slightly larger sizes but were able tomore » improve several aspects of the design.« less

Interface design and human factors considerations for model-based tight glycemic control in critical care.

PubMed

Ward, Logan; Steel, James; Le Compte, Aaron; Evans, Alicia; Tan, Chia-Siong; Penning, Sophie; Shaw, Geoffrey M; Desaive, Thomas; Chase, J Geoffrey

2012-01-01

Tight glycemic control (TGC) has shown benefits but has been difficult to implement. Model-based methods and computerized protocols offer the opportunity to improve TGC quality and compliance. This research presents an interface design to maximize compliance, minimize real and perceived clinical effort, and minimize error based on simple human factors and end user input. The graphical user interface (GUI) design is presented by construction based on a series of simple, short design criteria based on fundamental human factors engineering and includes the use of user feedback and focus groups comprising nursing staff at Christchurch Hospital. The overall design maximizes ease of use and minimizes (unnecessary) interaction and use. It is coupled to a protocol that allows nurse staff to select measurement intervals and thus self-manage workload. The overall GUI design is presented and requires only one data entry point per intervention cycle. The design and main interface are heavily focused on the nurse end users who are the predominant users, while additional detailed and longitudinal data, which are of interest to doctors guiding overall patient care, are available via tabs. This dichotomy of needs and interests based on the end user's immediate focus and goals shows how interfaces must adapt to offer different information to multiple types of users. The interface is designed to minimize real and perceived clinical effort, and ongoing pilot trials have reported high levels of acceptance. The overall design principles, approach, and testing methods are based on fundamental human factors principles designed to reduce user effort and error and are readily generalizable. © 2012 Diabetes Technology Society.

Interface Design and Human Factors Considerations for Model-Based Tight Glycemic Control in Critical Care

PubMed Central

Ward, Logan; Steel, James; Le Compte, Aaron; Evans, Alicia; Tan, Chia-Siong; Penning, Sophie; Shaw, Geoffrey M; Desaive, Thomas; Chase, J Geoffrey

2012-01-01

Introduction Tight glycemic control (TGC) has shown benefits but has been difficult to implement. Model-based methods and computerized protocols offer the opportunity to improve TGC quality and compliance. This research presents an interface design to maximize compliance, minimize real and perceived clinical effort, and minimize error based on simple human factors and end user input. Method The graphical user interface (GUI) design is presented by construction based on a series of simple, short design criteria based on fundamental human factors engineering and includes the use of user feedback and focus groups comprising nursing staff at Christchurch Hospital. The overall design maximizes ease of use and minimizes (unnecessary) interaction and use. It is coupled to a protocol that allows nurse staff to select measurement intervals and thus self-manage workload. Results The overall GUI design is presented and requires only one data entry point per intervention cycle. The design and main interface are heavily focused on the nurse end users who are the predominant users, while additional detailed and longitudinal data, which are of interest to doctors guiding overall patient care, are available via tabs. This dichotomy of needs and interests based on the end user's immediate focus and goals shows how interfaces must adapt to offer different information to multiple types of users. Conclusions The interface is designed to minimize real and perceived clinical effort, and ongoing pilot trials have reported high levels of acceptance. The overall design principles, approach, and testing methods are based on fundamental human factors principles designed to reduce user effort and error and are readily generalizable. PMID:22401330

Study of Fuze Structure and Reliability Design Based on the Direct Search Method

NASA Astrophysics Data System (ADS)

Lin, Zhang; Ning, Wang

2017-03-01

Redundant design is one of the important methods to improve the reliability of the system, but mutual coupling of multiple factors is often involved in the design. In my study, Direct Search Method is introduced into the optimum redundancy configuration for design optimization, in which, the reliability, cost, structural weight and other factors can be taken into account simultaneously, and the redundant allocation and reliability design of aircraft critical system are computed. The results show that this method is convenient and workable, and applicable to the redundancy configurations and optimization of various designs upon appropriate modifications. And this method has a good practical value.

Meaning profiles of dwellings, pathways, and metaphors in design: implications for education

NASA Astrophysics Data System (ADS)

Casakin, Hernan; Kreitler, Shulamith

2017-11-01

The study deals with the roles and interrelations of the meaning-based assessments of dwellings, pathways and metaphors in design performance. It is grounded in the Meaning Theory [Kreitler, S., and H. Kreitler. 1990. The Cognitive Foundations of Personality Traits. New York: Plenum], which enables identifying the cognitive contents and processes underlying cognitive performance in different domains, thus rendering them more accessible to educational training. The objectives were to identify the components of the meaning profiles of dwellings, pathways, and metaphors as perceived by design students; to analyse their interrelations; and to examine which of the identified components of these constructs serve as best predictors of design performance aided by the use of metaphors. Participants were administered a design task and questionnaires about the Dimensional Profiles of Dwellings, Pathways, and Metaphors, based on the meaning system. Factors based on the factor analyses of the responses to the three questionnaires were used in regression analyses as predictors of the performance score in a design task. The following three factors of the dimensional meaning profiles of metaphors were significant predictors of design performance: sensory, functional, and structural evaluations. Implications for design education are discussed, primarily concerning the important role of metaphor in design problem-solving.

Engineering synthetic TALE and CRISPR/Cas9 transcription factors for regulating gene expression.

PubMed

Kabadi, Ami M; Gersbach, Charles A

2014-09-01

Engineered DNA-binding proteins that can be targeted to specific sites in the genome to manipulate gene expression have enabled many advances in biomedical research. This includes generating tools to study fundamental aspects of gene regulation and the development of a new class of gene therapies that alter the expression of endogenous genes. Designed transcription factors have entered clinical trials for the treatment of human diseases and others are in preclinical development. High-throughput and user-friendly platforms for designing synthetic DNA-binding proteins present innovative methods for deciphering cell biology and designing custom synthetic gene circuits. We review two platforms for designing synthetic transcription factors for manipulating gene expression: Transcription activator-like effectors (TALEs) and the RNA-guided clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 system. We present an overview of each technology and a guide for designing and assembling custom TALE- and CRISPR/Cas9-based transcription factors. We also discuss characteristics of each platform that are best suited for different applications. Copyright © 2014 Elsevier Inc. All rights reserved.

Double-stranded RNA transcribed from vector-based oligodeoxynucleotide acts as transcription factor decoy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiao, Xiao; Gang, Yi; Department of Infectious Diseases, Tangdu Hospital, Fourth Military Medical University, Xi’an 710038, Shaanxi Province

2015-02-06

Highlights: • A shRNA vector based transcription factor decoy, VB-ODN, was designed. • VB-ODN for NF-κB inhibited cell viability in HEK293 cells. • VB-ODN inhibited expression of downstream genes of target transcription factors. • VB-ODN may enhance nuclear entry ratio for its feasibility of virus production. - Abstract: In this study, we designed a short hairpin RNA vector-based oligodeoxynucleotide (VB-ODN) carrying transcription factor (TF) consensus sequence which could function as a decoy to block TF activity. Specifically, VB-ODN for Nuclear factor-κB (NF-κB) could inhibit cell viability and decrease downstream gene expression in HEK293 cells without affecting expression of NF-κB itself.more » The specific binding between VB-ODN produced double-stranded RNA and NF-κB was evidenced by electrophoretic mobility shift assay. Moreover, similar VB-ODNs designed for three other TFs also inhibit their downstream gene expression but not that of themselves. Our study provides a new design of decoy for blocking TF activity.« less

Human factors engineering approaches to patient identification armband design.

PubMed

Probst, C Adam; Wolf, Laurie; Bollini, Mara; Xiao, Yan

2016-01-01

The task of patient identification is performed many times each day by nurses and other members of the care team. Armbands are used for both direct verification and barcode scanning during patient identification. Armbands and information layout are critical to reducing patient identification errors and dangerous workarounds. We report the effort at two large, integrated healthcare systems that employed human factors engineering approaches to the information layout design of new patient identification armbands. The different methods used illustrate potential pathways to obtain standardized armbands across healthcare systems that incorporate human factors principles. By extension, how the designs have been adopted provides examples of how to incorporate human factors engineering into key clinical processes. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Determination of Parachute Joint Factors using Seam and Joint Testing

NASA Technical Reports Server (NTRS)

Mollmann, Catherine

2015-01-01

This paper details the methodology for determining the joint factor for all parachute components. This method has been successfully implemented on the Capsule Parachute Assembly System (CPAS) for the NASA Orion crew module for use in determining the margin of safety for each component under peak loads. Also discussed are concepts behind the joint factor and what drives the loss of material strength at joints. The joint factor is defined as a "loss in joint strength...relative to the basic material strength" that occurs when "textiles are connected to each other or to metals." During the CPAS engineering development phase, a conservative joint factor of 0.80 was assumed for each parachute component. In order to refine this factor and eliminate excess conservatism, a seam and joint testing program was implemented as part of the structural validation. This method split each of the parachute structural joints into discrete tensile tests designed to duplicate the loading of each joint. Breaking strength data collected from destructive pull testing was then used to calculate the joint factor in the form of an efficiency. Joint efficiency is the percentage of the base material strength that remains after degradation due to sewing or interaction with other components; it is used interchangeably with joint factor in this paper. Parachute materials vary in type-mainly cord, tape, webbing, and cloth -which require different test fixtures and joint sample construction methods. This paper defines guidelines for designing and testing samples based on materials and test goals. Using the test methodology and analysis approach detailed in this paper, the minimum joint factor for each parachute component can be formulated. The joint factors can then be used to calculate the design factor and margin of safety for that component, a critical part of the design verification process.

Ranking factors affecting emissions of GHG from incubated agricultural soils.

PubMed

García-Marco, S; Ravella, S R; Chadwick, D; Vallejo, A; Gregory, A S; Cárdenas, L M

2014-07-01

Agriculture significantly contributes to global greenhouse gas (GHG) emissions and there is a need to develop effective mitigation strategies. The efficacy of methods to reduce GHG fluxes from agricultural soils can be affected by a range of interacting management and environmental factors. Uniquely, we used the Taguchi experimental design methodology to rank the relative importance of six factors known to affect the emission of GHG from soil: nitrate (NO 3 - ) addition, carbon quality (labile and non-labile C), soil temperature, water-filled pore space (WFPS) and extent of soil compaction. Grassland soil was incubated in jars where selected factors, considered at two or three amounts within the experimental range, were combined in an orthogonal array to determine the importance and interactions between factors with a L 16 design, comprising 16 experimental units. Within this L 16 design, 216 combinations of the full factorial experimental design were represented. Headspace nitrous oxide (N 2 O), methane (CH 4 ) and carbon dioxide (CO 2 ) concentrations were measured and used to calculate fluxes. Results found for the relative influence of factors (WFPS and NO 3 - addition were the main factors affecting N 2 O fluxes, whilst glucose, NO 3 - and soil temperature were the main factors affecting CO 2 and CH 4 fluxes) were consistent with those already well documented. Interactions between factors were also studied and results showed that factors with little individual influence became more influential in combination. The proposed methodology offers new possibilities for GHG researchers to study interactions between influential factors and address the optimized sets of conditions to reduce GHG emissions in agro-ecosystems, while reducing the number of experimental units required compared with conventional experimental procedures that adjust one variable at a time.

Ranking factors affecting emissions of GHG from incubated agricultural soils

PubMed Central

García-Marco, S; Ravella, S R; Chadwick, D; Vallejo, A; Gregory, A S; Cárdenas, L M

2014-01-01

Agriculture significantly contributes to global greenhouse gas (GHG) emissions and there is a need to develop effective mitigation strategies. The efficacy of methods to reduce GHG fluxes from agricultural soils can be affected by a range of interacting management and environmental factors. Uniquely, we used the Taguchi experimental design methodology to rank the relative importance of six factors known to affect the emission of GHG from soil: nitrate (NO3−) addition, carbon quality (labile and non-labile C), soil temperature, water-filled pore space (WFPS) and extent of soil compaction. Grassland soil was incubated in jars where selected factors, considered at two or three amounts within the experimental range, were combined in an orthogonal array to determine the importance and interactions between factors with a L16 design, comprising 16 experimental units. Within this L16 design, 216 combinations of the full factorial experimental design were represented. Headspace nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) concentrations were measured and used to calculate fluxes. Results found for the relative influence of factors (WFPS and NO3− addition were the main factors affecting N2O fluxes, whilst glucose, NO3− and soil temperature were the main factors affecting CO2 and CH4 fluxes) were consistent with those already well documented. Interactions between factors were also studied and results showed that factors with little individual influence became more influential in combination. The proposed methodology offers new possibilities for GHG researchers to study interactions between influential factors and address the optimized sets of conditions to reduce GHG emissions in agro-ecosystems, while reducing the number of experimental units required compared with conventional experimental procedures that adjust one variable at a time. PMID:25177207

Human Factors in the Design and Evaluation of Air Traffic Control Systems

DOT National Transportation Integrated Search

1995-04-01

This document presents human factors issues that should be considered in the design and evaluation of air traffic : control (ATC) systems and subsystems. It provides background material on the capabilities and limitations of humans as : information p...

Factors affecting consumer usage and acceptance of child restraints

DOT National Transportation Integrated Search

1983-09-01

This study was designed to focus on two factors with potential relevance to the child restraint device (CRD) usage problem: CRD design and directions for use; problems of initial users and repeated users were targeted for consideration. Ultimate obje...

A Human Factors Framework for Payload Display Design

NASA Technical Reports Server (NTRS)

Dunn, Mariea C.; Hutchinson, Sonya L.

1998-01-01

During missions to space, one charge of the astronaut crew is to conduct research experiments. These experiments, referred to as payloads, typically are controlled by computers. Crewmembers interact with payload computers by using visual interfaces or displays. To enhance the safety, productivity, and efficiency of crewmember interaction with payload displays, particular attention must be paid to the usability of these displays. Enhancing display usability requires adoption of a design process that incorporates human factors engineering principles at each stage. This paper presents a proposed framework for incorporating human factors engineering principles into the payload display design process.

Helicopter Transparent Enclosures. Volume 1. Design Handbook

DTIC Science & Technology

1979-01-01

Armour Research Foundation, "Engineering Design Factors for Laminated Aircraft Windshields, Part 2," WADC-TR-53-99, Wright Air Devel- opment Center...77L~i- -- - -- References .. l,. Islir~ger, Armour Research Foundation, "Engineering Design Factors for Laminated Aircraft Windshields, Parts 1 ahd I...of having separate heating and forming devices, often used with acrylic, will rarely be feasible with polycarbonates. 29.7 Forming Methods Drape

A Comparative Analysis of the Effects of Instructional Design Factors on Student Success in E-Learning: Multiple-Regression versus Neural Networks

ERIC Educational Resources Information Center

Cebeci, Halil Ibrahim; Yazgan, Harun Resit; Geyik, Abdulkadir

2009-01-01

This study explores the relationship between the student performance and instructional design. The research was conducted at the E-Learning School at a university in Turkey. A list of design factors that had potential influence on student success was created through a review of the literature and interviews with relevant experts. From this, the…

Reliability-based criteria for load and resistance factor design code for wood bridges

Treesearch

Chris Eamon; Andrzej S. Nowak; Michael A. Ritter; Joe Murphy

2000-01-01

Recently AASHTO adopted a load and resistance factor design code for highway bridges. The new code provides a rational basis for the design of steel and concrete structures. However, the calibration was not done for wood bridges. Therefore, there is a need to fill this gap. The development of statistical models for wood bridge structures is discussed. Recent test...

Biological, social, and urban design factors affecting young street tree mortality in New York City

Treesearch

Jacqueline W.T. Lu; Erika S. Svendsen; Lindsay K. Campbell; Jennifer Greenfeld; Jessie Braden; Kristen King; Nancy Falxa-Raymond

2010-01-01

In dense metropolitan areas, there are many factors including traffic congestion, building development and social organizations that may impact the health of street trees. The focus of this study is to better understand how social, biological and urban design factors affect the mortality rates of newly planted street trees. Prior analyses of street trees planted by the...

The Work Design Method for Human Friendly

NASA Astrophysics Data System (ADS)

Harada, Narumi; Sasaki, Masatoshi; Ichikawa, Masami

In order to realize “the product life cycle with respect for human nature". we ought to make work design so that work environment should be configured to be sound in mind and body, with due consideration of not only physical but also mental factors from the viewpoint of workers. The former includes too heavy work, unreasonable working posture, local fatigue of the body, the safety, and working comfort, and the latter includes work motivation, work worthiness, stress, etc. For the purpose of evaluating the degree of working comfort and safety at human-oriented production lines, we acknowledged, for the work design, the effectiveness of the work designing technique with working time variation duly considered. And, we formulated a model for a mental factor experienced by workers from the degree of working delays. This study covers a work design technique we developed with the effect of the factor as the value of evaluation.

Research on design method of the full form ship with minimum thrust deduction factor

NASA Astrophysics Data System (ADS)

Zhang, Bao-ji; Miao, Ai-qin; Zhang, Zhu-xin

2015-04-01

In the preliminary design stage of the full form ships, in order to obtain a hull form with low resistance and maximum propulsion efficiency, an optimization design program for a full form ship with the minimum thrust deduction factor has been developed, which combined the potential flow theory and boundary layer theory with the optimization technique. In the optimization process, the Sequential Unconstrained Minimization Technique (SUMT) interior point method of Nonlinear Programming (NLP) was proposed with the minimum thrust deduction factor as the objective function. An appropriate displacement is a basic constraint condition, and the boundary layer separation is an additional one. The parameters of the hull form modification function are used as design variables. At last, the numerical optimization example for lines of after-body of 50000 DWT product oil tanker was provided, which indicated that the propulsion efficiency was improved distinctly by this optimal design method.

Mapping lexical-semantic networks and determining hemispheric language dominance: Do task design, sex, age, and language performance make a difference?

PubMed

Chang, Yu-Hsuan A; Javadi, Sogol S; Bahrami, Naeim; Uttarwar, Vedang S; Reyes, Anny; McDonald, Carrie R

2018-04-01

Blocked and event-related fMRI designs are both commonly used to localize language networks and determine hemispheric dominance in research and clinical settings. We compared activation profiles on a semantic monitoring task using one of the two designs in a total of 43 healthy individual to determine whether task design or subject-specific factors (i.e., age, sex, or language performance) influence activation patterns. We found high concordance between the two designs within core language regions, including the inferior frontal, posterior temporal, and basal temporal region. However, differences emerged within inferior parietal cortex. Subject-specific factors did not influence activation patterns, nor did they interact with task design. These results suggest that despite high concordance within perisylvian regions that are robust to subject-specific factors, methodological differences between blocked and event-related designs may contribute to parietal activations. These findings provide important information for researchers incorporating fMRI results into meta-analytic studies, as well as for clinicians using fMRI to guide pre-surgical planning. Copyright © 2018 Elsevier Inc. All rights reserved.

46 CFR 11.305 - Radar-Observer certificates and qualifying courses.

Code of Federal Regulations, 2011 CFR

2011-10-01

... appropriate curriculum as follows: (1) Radar Observer (Unlimited). Classroom instruction—including... conditions. (D) Limitations of radar resulting from design factors. (E) Safety precautions associated with...) Limitations of radar resulting from design factors. (E) Safety precautions associated with use and maintenance...

Aragon workers' health study - design and cohort description

USDA-ARS?s Scientific Manuscript database

Spain, a Mediterranean country with relatively low rates of coronary heart disease, has a high prevalence of traditional cardiovascular risk factors and is experiencing a severe epidemic of overweight/obesity. We designed the Aragon Workers' Health Study (AWHS) to characterize the factors associated...

Analysis of time domain reflectometry data from LTPP seasonal monitoring program test sections

DOT National Transportation Integrated Search

1996-07-01

This report documents an approach for designing an Advanced Traffic Management System (ATMS) from a human factors perspective. In designing the ATMS from a human factors perspective, a user-centered top-down system analysis was conducted. Methodologi...

Hardware-Based Non-Optimum Factors for Launch Vehicle Structural Design

NASA Technical Reports Server (NTRS)

Wu, K. Chauncey; Cerro, Jeffrey A.

2010-01-01

During aerospace vehicle conceptual and preliminary design, empirical non-optimum factors are typically applied to predicted structural component weights to account for undefined manufacturing and design details. Non-optimum factors are developed here for 32 aluminum-lithium 2195 orthogrid panels comprising the liquid hydrogen tank barrel of the Space Shuttle External Tank using measured panel weights and manufacturing drawings. Minimum values for skin thickness, axial and circumferential blade stiffener thickness and spacing, and overall panel thickness are used to estimate individual panel weights. Panel non-optimum factors computed using a coarse weights model range from 1.21 to 1.77, and a refined weights model (including weld lands and skin and stiffener transition details) yields non-optimum factors of between 1.02 and 1.54. Acreage panels have an average 1.24 non-optimum factor using the coarse model, and 1.03 with the refined version. The observed consistency of these acreage non-optimum factors suggests that relatively simple models can be used to accurately predict large structural component weights for future launch vehicles.

Controlling gene networks and cell fate with precision-targeted DNA-binding proteins and small-molecule-based genome readers

PubMed Central

Eguchi, Asuka; Lee, Garrett O.; Wan, Fang; Erwin, Graham S.; Ansari, Aseem Z.

2014-01-01

Transcription factors control the fate of a cell by regulating the expression of genes and regulatory networks. Recent successes in inducing pluripotency in terminally differentiated cells as well as directing differentiation with natural transcription factors has lent credence to the efforts that aim to direct cell fate with rationally designed transcription factors. Because DNA-binding factors are modular in design, they can be engineered to target specific genomic sequences and perform pre-programmed regulatory functions upon binding. Such precision-tailored factors can serve as molecular tools to reprogramme or differentiate cells in a targeted manner. Using different types of engineered DNA binders, both regulatory transcriptional controls of gene networks, as well as permanent alteration of genomic content, can be implemented to study cell fate decisions. In the present review, we describe the current state of the art in artificial transcription factor design and the exciting prospect of employing artificial DNA-binding factors to manipulate the transcriptional networks as well as epigenetic landscapes that govern cell fate. PMID:25145439

Investigation of Fundamental Modeling and Thermal Performance Issues for a Metallic Thermal Protection System Design

NASA Technical Reports Server (NTRS)

Blosser, Max L.

2002-01-01

A study was performed to develop an understanding of the key factors that govern the performance of metallic thermal protection systems for reusable launch vehicles. A current advanced metallic thermal protection system (TPS) concept was systematically analyzed to discover the most important factors governing the thermal performance of metallic TPS. A large number of relevant factors that influence the thermal analysis and thermal performance of metallic TPS were identified and quantified. Detailed finite element models were developed for predicting the thermal performance of design variations of the advanced metallic TPS concept mounted on a simple, unstiffened structure. The computational models were also used, in an automated iterative procedure, for sizing the metallic TPS to maintain the structure below a specified temperature limit. A statistical sensitivity analysis method, based on orthogonal matrix techniques used in robust design, was used to quantify and rank the relative importance of the various modeling and design factors considered in this study. Results of the study indicate that radiation, even in small gaps between panels, can reduce significantly the thermal performance of metallic TPS, so that gaps should be eliminated by design if possible. Thermal performance was also shown to be sensitive to several analytical assumptions that should be chosen carefully. One of the factors that was found to have the greatest effect on thermal performance is the heat capacity of the underlying structure. Therefore the structure and TPS should be designed concurrently.

Time-oriented experimental design method to optimize hydrophilic matrix formulations with gelation kinetics and drug release profiles.

PubMed

Shin, Sangmun; Choi, Du Hyung; Truong, Nguyen Khoa Viet; Kim, Nam Ah; Chu, Kyung Rok; Jeong, Seong Hoon

2011-04-04

A new experimental design methodology was developed by integrating the response surface methodology and the time series modeling. The major purposes were to identify significant factors in determining swelling and release rate from matrix tablets and their relative factor levels for optimizing the experimental responses. Properties of tablet swelling and drug release were assessed with ten factors and two default factors, a hydrophilic model drug (terazosin) and magnesium stearate, and compared with target values. The selected input control factors were arranged in a mixture simplex lattice design with 21 experimental runs. The obtained optimal settings for gelation were PEO, LH-11, Syloid, and Pharmacoat with weight ratios of 215.33 (88.50%), 5.68 (2.33%), 19.27 (7.92%), and 3.04 (1.25%), respectively. The optimal settings for drug release were PEO and citric acid with weight ratios of 191.99 (78.91%) and 51.32 (21.09%), respectively. Based on the results of matrix swelling and drug release, the optimal solutions, target values, and validation experiment results over time were similar and showed consistent patterns with very small biases. The experimental design methodology could be a very promising experimental design method to obtain maximum information with limited time and resources. It could also be very useful in formulation studies by providing a systematic and reliable screening method to characterize significant factors in the sustained release matrix tablet. Copyright © 2011 Elsevier B.V. All rights reserved.

A designed screening study with prespecified combinations of factor settings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson-cook, Christine M; Robinson, Timothy J

2009-01-01

In many applications, the experimenter has limited options about what factor combinations can be chosen for a designed study. Consider a screening study for a production process involving five input factors whose levels have been previously established. The goal of the study is to understand the effect of each factor on the response, a variable that is expensive to measure and results in destruction of the part. From an inventory of available parts with known factor values, we wish to identify a best collection of factor combinations with which to estimate the factor effects. Though the observational nature of themore » study cannot establish a causal relationship involving the response and the factors, the study can increase understanding of the underlying process. The study can also help determine where investment should be made to control input factors during production that will maximally influence the response. Because the factor combinations are observational, the chosen model matrix will be nonorthogonal and will not allow independent estimation of factor effects. In this manuscript we borrow principles from design of experiments to suggest an 'optimal' selection of factor combinations. Specifically, we consider precision of model parameter estimates, the issue of replication, and abilities to detect lack of fit and to estimate two-factor interactions. Through an example, we present strategies for selecting a subset of factor combinations that simultaneously balance multiple objectives, conduct a limited sensitivity analysis, and provide practical guidance for implementing our techniques across a variety of quality engineering disciplines.« less

Optimization of the Ion Source-Mass Spectrometry Parameters in Non-Steroidal Anti-Inflammatory and Analgesic Pharmaceuticals Analysis by a Design of Experiments Approach.

PubMed

Paíga, Paula; Silva, Luís M S; Delerue-Matos, Cristina

2016-10-01

The flow rates of drying and nebulizing gas, heat block and desolvation line temperatures and interface voltage are potential electrospray ionization parameters as they may enhance sensitivity of the mass spectrometer. The conditions that give higher sensitivity of 13 pharmaceuticals were explored. First, Plackett-Burman design was implemented to screen significant factors, and it was concluded that interface voltage and nebulizing gas flow were the only factors that influence the intensity signal for all pharmaceuticals. This fractionated factorial design was projected to set a full 2(2) factorial design with center points. The lack-of-fit test proved to be significant. Then, a central composite face-centered design was conducted. Finally, a stepwise multiple linear regression and subsequently an optimization problem solving were carried out. Two main drug clusters were found concerning the signal intensities of all runs of the augmented factorial design. p-Aminophenol, salicylic acid, and nimesulide constitute one cluster as a result of showing much higher sensitivity than the remaining drugs. The other cluster is more homogeneous with some sub-clusters comprising one pharmaceutical and its respective metabolite. It was observed that instrumental signal increased when both significant factors increased with maximum signal occurring when both codified factors are set at level +1. It was also found that, for most of the pharmaceuticals, interface voltage influences the intensity of the instrument more than the nebulizing gas flowrate. The only exceptions refer to nimesulide where the relative importance of the factors is reversed and still salicylic acid where both factors equally influence the instrumental signal. Graphical Abstract ᅟ.

Design of Critical Components

NASA Technical Reports Server (NTRS)

Hendricks, Robert C.; Zaretsky, Erwin V.

2001-01-01

Critical component design is based on minimizing product failures that results in loss of life. Potential catastrophic failures are reduced to secondary failures where components removed for cause or operating time in the system. Issues of liability and cost of component removal become of paramount importance. Deterministic design with factors of safety and probabilistic design address but lack the essential characteristics for the design of critical components. In deterministic design and fabrication there are heuristic rules and safety factors developed over time for large sets of structural/material components. These factors did not come without cost. Many designs failed and many rules (codes) have standing committees to oversee their proper usage and enforcement. In probabilistic design, not only are failures a given, the failures are calculated; an element of risk is assumed based on empirical failure data for large classes of component operations. Failure of a class of components can be predicted, yet one can not predict when a specific component will fail. The analogy is to the life insurance industry where very careful statistics are book-kept on classes of individuals. For a specific class, life span can be predicted within statistical limits, yet life-span of a specific element of that class can not be predicted.

The Effect of Visual Cueing and Control Design on Children's Reading Achievement of Audio E-Books with Tablet Computers

ERIC Educational Resources Information Center

Wang, Pei-Yu; Huang, Chung-Kai

2015-01-01

This study aims to explore the impact of learner grade, visual cueing, and control design on children's reading achievement of audio e-books with tablet computers. This research was a three-way factorial design where the first factor was learner grade (grade four and six), the second factor was e-book visual cueing (word-based, line-based, and…

Human Factors Engineering Guidelines for Overhead Cranes

NASA Technical Reports Server (NTRS)

Chandler, Faith; Delgado, H. (Technical Monitor)

2001-01-01

This guideline provides standards for overhead crane cabs that can be applied to the design and modification of crane cabs to reduce the potential for human error due to design. This guideline serves as an aid during the development of a specification for purchases of cranes or for an engineering support request for crane design modification. It aids human factors engineers in evaluating existing cranes during accident investigations or safety reviews.

Pilot Cueing Synergies for Degraded Visual Environments

DTIC Science & Technology

2016-02-19

Tactile displays: Guidance for their design and application. Human Factors: The Journal of the Human Factors and Ergonomics Society, 90-111. Kenny, C. W... designated to request documents from DTIC. Change of Address Organizations receiving reports from the U.S. Army Aeromedical Research Laboratory on...author(s) and should not be construed as an official Department of the Army position, policy, or decision, unless so designated by other official

An alternative method for centrifugal compressor loading factor modelling

NASA Astrophysics Data System (ADS)

Galerkin, Y.; Drozdov, A.; Rekstin, A.; Soldatova, K.

2017-08-01

The loading factor at design point is calculated by one or other empirical formula in classical design methods. Performance modelling as a whole is out of consideration. Test data of compressor stages demonstrates that loading factor versus flow coefficient at the impeller exit has a linear character independent of compressibility. Known Universal Modelling Method exploits this fact. Two points define the function - loading factor at design point and at zero flow rate. The proper formulae include empirical coefficients. A good modelling result is possible if the choice of coefficients is based on experience and close analogs. Earlier Y. Galerkin and K. Soldatova had proposed to define loading factor performance by the angle of its inclination to the ordinate axis and by the loading factor at zero flow rate. Simple and definite equations with four geometry parameters were proposed for loading factor performance calculated for inviscid flow. The authors of this publication have studied the test performance of thirteen stages of different types. The equations are proposed with universal empirical coefficients. The calculation error lies in the range of plus to minus 1,5%. The alternative model of a loading factor performance modelling is included in new versions of the Universal Modelling Method.

Survey of factors influencing learner engagement with simulation debriefing among nursing students.

PubMed

Roh, Young Sook; Jang, Kie In

2017-12-01

Simulation-based education has escalated worldwide, yet few studies have rigorously explored predictors of learner engagement with simulation debriefing. The purpose of this cross-sectional, descriptive survey was to identify factors that determine learner engagement with simulation debriefing among nursing students. A convenience sample of 296 Korean nursing students enrolled in the simulation-based course completed the survey. A total of five instruments were used: (i) Characteristics of Debriefing; (ii) Debriefing Assessment for Simulation in Healthcare - Student Version; (iii) The Korean version of the Simulation Design Scale; (iv) Communication Skills Scale; and (v) Clinical-Based Stress Scale. Multiple regression analysis was performed using the variables to investigate the influencing factors. The results indicated that influencing factors of learning engagement with simulation debriefing were simulation design, confidentiality, stress, and number of students. Simulation design was the most important factor. Video-assisted debriefing was not a significant factor affecting learner engagement. Educators should organize and conduct debriefing activities while considering these factors to effectively induce learner engagement. Further study is needed to identify the effects of debriefing sessions targeting learners' needs and considering situational factors on learning outcomes. © 2017 John Wiley & Sons Australia, Ltd.

Analysis of a Preloaded Bolted Joint in a Ceramic Composite Combustor

NASA Technical Reports Server (NTRS)

Hissam, D. Andy; Bower, Mark V.

2003-01-01

This paper presents the detailed analysis of a preloaded bolted joint incorporating ceramic materials. The objective of this analysis is to determine the suitability of a joint design for a ceramic combustor. The analysis addresses critical factors in bolted joint design including preload, preload uncertainty, and load factor. The relationship between key joint variables is also investigated. The analysis is based on four key design criteria, each addressing an anticipated failure mode. The criteria are defined in terms of margin of safety, which must be greater than zero for the design criteria to be satisfied. Since the proposed joint has positive margins of safety, the design criteria are satisfied. Therefore, the joint design is acceptable.

Proceedings of the Human Factors Society 35th annual meeting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1991-01-01

These volumes cover the proceedings of the 35th annual meeting of the Human Factors Society. Topics include: designing for the future of nuclear power plants international perspectives on advanced control room design; human performance assessment in the nuclear power industry; validity of strength tests for predicting endurance of coal miners, psychosocial issues in hazard management and nuclear power plants; and human factors at the DOE's national laboratories.

12 CFR 1320.10 - Factors for consideration in designations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... FINANCIAL MARKET UTILITIES Consultations, Determinations and Hearings § 1320.10 Factors for consideration in designations. In making any proposed or final determination with respect to whether a financial market utility... consideration: (a) The aggregate monetary value of transactions processed by the financial market utility...

12 CFR 1320.10 - Factors for consideration in designations.

Code of Federal Regulations, 2012 CFR

2012-01-01

... MARKET UTILITIES Consultations, Determinations and Hearings § 1320.10 Factors for consideration in designations. In making any proposed or final determination with respect to whether a financial market utility... consideration: (a) The aggregate monetary value of transactions processed by the financial market utility...

12 CFR 1320.10 - Factors for consideration in designations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... MARKET UTILITIES Consultations, Determinations and Hearings § 1320.10 Factors for consideration in designations. In making any proposed or final determination with respect to whether a financial market utility... consideration: (a) The aggregate monetary value of transactions processed by the financial market utility...

Guidelines for the design and evaluation of human factors aspects of automated guideway transit systems

DOT National Transportation Integrated Search

1979-03-01

This document has been compiled to provide guidance in the planning, design, fabrication, and evaluation of human factors aspects of Automated Guideway Transit (AGT) Systems, including Downtown People Mover (DPM) systems. It is based on the present s...

DESIGN OF FIELD STUDIES FOR THE MEASUREMENT OF BAFS AND BSAFS.

EPA Science Inventory

Bioaccumulation factors (BAFs) and biota-sediment accumulation factors (BSAFs) for aquatic organisms are necessary parameters for assessing the ecological risks of nonpolar organic chemicals in aquatic ecosystems. In designing a field study to measure BAFs and/or BSAFs, one of th...

Research and implementation of role-playing teaching mode supported by gamification

NASA Astrophysics Data System (ADS)

Cui, Xu; Zhang, Zhenglei; Sun, Lei

2017-08-01

The paper designs a Role-playing Teaching Mode Supported by Gamification to stimulate the interest of learners. In the process of creating the teaching mode, the factors of incentive factors, teaching mode and course selection are the most important factors gained by investigate and research. Then under the guidance of the three factors, a leaning framework of role-playing teaching mode which is called Gamification Learning Framework (GM1.0) is determined. In the design of GM1.0, First, collect problem cases which students interested in and select three courses which are Algorithm Design, Data Structure and Program Design. Then, extract the knowledge points of the three courses and merge into the problem cases to form game maps. Last, Learners gain a role-playing actor to join games with the support of game maps and finish selected tasks reaching a higher task level by upgrade checkpoints, experience promotions and award medals changing. After that, learners’ enthusiasm for learning can be stimulated and the innovation abilities can also be improved gradually.

A broader consideration of human factor to enhance sustainable building design.

PubMed

Attaianese, Erminia

2012-01-01

The link between ergonomic/human factor and sustainability seems to be clearly evidenced mainly in relation to social dimension of sustainability, in order to contribute to assure corporate social responsibility and global value creation. But the will to establish an equilibrated connection among used resources in human activities, supported by the sustainability perspective, evidences that the contribution of ergonomics/human factors can be effectively enlarged to other aspects, especially in relation to building design. In fact a sustainable building is meant to be a building that contributes, through its characteristics and attribute, to a sustainable development by assuring, in the same time, a decrease of resources use and environmental impact and an increase of health, safety and comfort of the occupants. The purpose of this paper is to analyze in a broader sense the contribution of ergonomic/human factor to design of sustainable building, focusing how ergonomics principles, methodology and techniques can improve building design, enhancing its sustainability performance during all phases of building lifecycle.

Design principles for therapeutic angiogenic materials

NASA Astrophysics Data System (ADS)

Briquez, Priscilla S.; Clegg, Lindsay E.; Martino, Mikaël M.; Gabhann, Feilim Mac; Hubbell, Jeffrey A.

2016-01-01

Despite extensive research, pro-angiogenic drugs have failed to translate clinically, and therapeutic angiogenesis, which has potential in the treatment of various cardiovascular diseases, remains a major challenge. Physiologically, angiogenesis — the process of blood-vessel growth from existing vasculature — is regulated by a complex interplay of biophysical and biochemical cues from the extracellular matrix (ECM), angiogenic factors and multiple cell types. The ECM can be regarded as the natural 3D material that regulates angiogenesis. Here, we leverage knowledge of ECM properties to derive design rules for engineering pro-angiogenic materials. We propose that pro-angiogenic materials should be biomimetic, incorporate angiogenic factors and mimic cooperative interactions between growth factors and the ECM. We highlight examples of material designs that demonstrate these principles and considerations for designing better angiogenic materials.

Human Factors Analysis to Improve the Processing of Ares-1 Launch Vehicle

NASA Technical Reports Server (NTRS)

Stambolian, Damon B.; Dippolito, Gregory M.; Nyugen, Bao; Dischinger, Charles; Tran, Donald; Henderson, Gena; Barth, Tim

2011-01-01

This slide presentation reviews the use of Human Factors analysis in improving the ground processing procedures for the Ares-1 launch vehicle. The light vehicle engineering designers for Ares-l launch vehicle had to design the flight vehicle for effective, efficient and safe ground operations in the cramped dimensions in a rocket design. The use of a mockup of the area where the technician would be required to work proved to be a very effective method to promote the collaboration between the Ares-1 designers and the ground operations personnel.

Global sustainability and key needs in future automotive design.

PubMed

McAuley, John W

2003-12-01

The number of light vehicle registrations is forecast to increase worldwide by a factor of 3-5 over the next 50 years. This will dramatically increase environmental impacts worldwide of automobiles and light trucks. If light vehicles are to be environmentally sustainable globally, the automotive industry must implement fundamental changes in future automotive design. Important factors in assessing automobile design needs include fuel economy and reduced emissions. Many design parameters can impact vehicle air emissions and energy consumption including alternative fuel or engine technologies, rolling resistance, aerodynamics, drive train design, friction, and vehicle weight. Of these, vehicle weight is key and will translate into reduced energy demand across all energy distribution elements. A new class of vehicles is needed that combines ultra-light design with a likely hybrid or fuel cell engine technology. This could increase efficiency by a factor of 3-5 and reduce air emissions as well. Advanced lightweight materials, such as plastics or composites, will need to overtake the present metal-based infrastructure. Incorporating design features to facilitate end-of-life recycling and recovery is also important. The trend will be towards fewer materials and parts in vehicle design, combined with ease of disassembly. Mono-material construction can create vehicle design with improved recyclability as well as reduced numbers of parts and weight.

Evaluation of the flood risk factor in the design of box culverts, volume 1 : theoretical development.

DOT National Transportation Integrated Search

1979-09-01

"The work presented in this report represents a preliminary effort to integrate economic factors with the physics of highway drainage. Conventional culvert design rests on the selection of a flood peak flow having a particular return period; for exam...

Factors Influencing the Design, Establishment, Administration, and Governance of Correctional Education for Females

ERIC Educational Resources Information Center

Ellis, Johnica; McFadden, Cheryl; Colaric, Susan

2008-01-01

This article summarizes the results of a study conducted to investigate factors influencing the organizational design, establishment, administration, and governance of correctional education for females. The research involved interviews with correctional and community college administrators and practitioners representing North Carolina female…

A Holistic Approach to Systems Development

NASA Technical Reports Server (NTRS)

Wong, Douglas T.

2008-01-01

Introduces a Holistic and Iterative Design Process. Continuous process but can be loosely divided into four stages. More effort spent early on in the design. Human-centered and Multidisciplinary. Emphasis on Life-Cycle Cost. Extensive use of modeling, simulation, mockups, human subjects, and proven technologies. Human-centered design doesn t mean the human factors discipline is the most important Disciplines should be involved in the design: Subsystem vendors, configuration management, operations research, manufacturing engineering, simulation/modeling, cost engineering, hardware engineering, software engineering, test and evaluation, human factors, electromagnetic compatibility, integrated logistics support, reliability/maintainability/availability, safety engineering, test equipment, training systems, design-to-cost, life cycle cost, application engineering etc. 9

A new experimental design method to optimize formulations focusing on a lubricant for hydrophilic matrix tablets.

PubMed

Choi, Du Hyung; Shin, Sangmun; Khoa Viet Truong, Nguyen; Jeong, Seong Hoon

2012-09-01

A robust experimental design method was developed with the well-established response surface methodology and time series modeling to facilitate the formulation development process with magnesium stearate incorporated into hydrophilic matrix tablets. Two directional analyses and a time-oriented model were utilized to optimize the experimental responses. Evaluations of tablet gelation and drug release were conducted with two factors x₁ and x₂: one was a formulation factor (the amount of magnesium stearate) and the other was a processing factor (mixing time), respectively. Moreover, different batch sizes (100 and 500 tablet batches) were also evaluated to investigate an effect of batch size. The selected input control factors were arranged in a mixture simplex lattice design with 13 experimental runs. The obtained optimal settings of magnesium stearate for gelation were 0.46 g, 2.76 min (mixing time) for a 100 tablet batch and 1.54 g, 6.51 min for a 500 tablet batch. The optimal settings for drug release were 0.33 g, 7.99 min for a 100 tablet batch and 1.54 g, 6.51 min for a 500 tablet batch. The exact ratio and mixing time of magnesium stearate could be formulated according to the resulting hydrophilic matrix tablet properties. The newly designed experimental method provided very useful information for characterizing significant factors and hence to obtain optimum formulations allowing for a systematic and reliable experimental design method.

Improving social connection through a communities-of-practice-inspired cognitive work analysis approach.

PubMed

Euerby, Adam; Burns, Catherine M

2014-03-01

Increasingly, people work in socially networked environments. With growing adoption of enterprise social network technologies, supporting effective social community is becoming an important factor in organizational success. Relatively few human factors methods have been applied to social connection in communities. Although team methods provide a contribution, they do not suit design for communities. Wenger's community of practice concept, combined with cognitive work analysis, provided one way of designing for community. We used a cognitive work analysis approach modified with principles for supporting communities of practice to generate a new website design. Over several months, the community using the site was studied to examine their degree of social connectedness and communication levels. Social network analysis and communications analysis, conducted at three different intervals, showed increases in connections between people and between people and organizations, as well as increased communication following the launch of the new design. In this work, we suggest that human factors approaches can be effective in social environments, when applied considering social community principles. This work has implications for the development of new human factors methods as well as the design of interfaces for sociotechnical systems that have community building requirements.

Piezoresistive Cantilever Performance—Part I: Analytical Model for Sensitivity

PubMed Central

Park, Sung-Jin; Doll, Joseph C.; Pruitt, Beth L.

2010-01-01

An accurate analytical model for the change in resistance of a piezoresistor is necessary for the design of silicon piezoresistive transducers. Ion implantation requires a high-temperature oxidation or annealing process to activate the dopant atoms, and this treatment results in a distorted dopant profile due to diffusion. Existing analytical models do not account for the concentration dependence of piezoresistance and are not accurate for nonuniform dopant profiles. We extend previous analytical work by introducing two nondimensional factors, namely, the efficiency and geometry factors. A practical benefit of this efficiency factor is that it separates the process parameters from the design parameters; thus, designers may address requirements for cantilever geometry and fabrication process independently. To facilitate the design process, we provide a lookup table for the efficiency factor over an extensive range of process conditions. The model was validated by comparing simulation results with the experimentally determined sensitivities of piezoresistive cantilevers. We performed 9200 TSUPREM4 simulations and fabricated 50 devices from six unique process flows; we systematically explored the design space relating process parameters and cantilever sensitivity. Our treatment focuses on piezoresistive cantilevers, but the analytical sensitivity model is extensible to other piezoresistive transducers such as membrane pressure sensors. PMID:20336183

Piezoresistive Cantilever Performance-Part I: Analytical Model for Sensitivity.

PubMed

Park, Sung-Jin; Doll, Joseph C; Pruitt, Beth L

2010-02-01

An accurate analytical model for the change in resistance of a piezoresistor is necessary for the design of silicon piezoresistive transducers. Ion implantation requires a high-temperature oxidation or annealing process to activate the dopant atoms, and this treatment results in a distorted dopant profile due to diffusion. Existing analytical models do not account for the concentration dependence of piezoresistance and are not accurate for nonuniform dopant profiles. We extend previous analytical work by introducing two nondimensional factors, namely, the efficiency and geometry factors. A practical benefit of this efficiency factor is that it separates the process parameters from the design parameters; thus, designers may address requirements for cantilever geometry and fabrication process independently. To facilitate the design process, we provide a lookup table for the efficiency factor over an extensive range of process conditions. The model was validated by comparing simulation results with the experimentally determined sensitivities of piezoresistive cantilevers. We performed 9200 TSUPREM4 simulations and fabricated 50 devices from six unique process flows; we systematically explored the design space relating process parameters and cantilever sensitivity. Our treatment focuses on piezoresistive cantilevers, but the analytical sensitivity model is extensible to other piezoresistive transducers such as membrane pressure sensors.

A Probabilistic Design Method Applied to Smart Composite Structures

NASA Technical Reports Server (NTRS)

Shiao, Michael C.; Chamis, Christos C.

1995-01-01

A probabilistic design method is described and demonstrated using a smart composite wing. Probabilistic structural design incorporates naturally occurring uncertainties including those in constituent (fiber/matrix) material properties, fabrication variables, structure geometry and control-related parameters. Probabilistic sensitivity factors are computed to identify those parameters that have a great influence on a specific structural reliability. Two performance criteria are used to demonstrate this design methodology. The first criterion requires that the actuated angle at the wing tip be bounded by upper and lower limits at a specified reliability. The second criterion requires that the probability of ply damage due to random impact load be smaller than an assigned value. When the relationship between reliability improvement and the sensitivity factors is assessed, the results show that a reduction in the scatter of the random variable with the largest sensitivity factor (absolute value) provides the lowest failure probability. An increase in the mean of the random variable with a negative sensitivity factor will reduce the failure probability. Therefore, the design can be improved by controlling or selecting distribution parameters associated with random variables. This can be implemented during the manufacturing process to obtain maximum benefit with minimum alterations.

Sociotechnical attributes of safe and unsafe work systems.

PubMed

Kleiner, Brian M; Hettinger, Lawrence J; DeJoy, David M; Huang, Yuang-Hsiang; Love, Peter E D

2015-01-01

Theoretical and practical approaches to safety based on sociotechnical systems principles place heavy emphasis on the intersections between social-organisational and technical-work process factors. Within this perspective, work system design emphasises factors such as the joint optimisation of social and technical processes, a focus on reliable human-system performance and safety metrics as design and analysis criteria, the maintenance of a realistic and consistent set of safety objectives and policies, and regular access to the expertise and input of workers. We discuss three current approaches to the analysis and design of complex sociotechnical systems: human-systems integration, macroergonomics and safety climate. Each approach emphasises key sociotechnical systems themes, and each prescribes a more holistic perspective on work systems than do traditional theories and methods. We contrast these perspectives with historical precedents such as system safety and traditional human factors and ergonomics, and describe potential future directions for their application in research and practice. The identification of factors that can reliably distinguish between safe and unsafe work systems is an important concern for ergonomists and other safety professionals. This paper presents a variety of sociotechnical systems perspectives on intersections between social--organisational and technology--work process factors as they impact work system analysis, design and operation.

Unbalanced and Minimal Point Equivalent Estimation Second-Order Split-Plot Designs

NASA Technical Reports Server (NTRS)

Parker, Peter A.; Kowalski, Scott M.; Vining, G. Geoffrey

2007-01-01

Restricting the randomization of hard-to-change factors in industrial experiments is often performed by employing a split-plot design structure. From an economic perspective, these designs minimize the experimental cost by reducing the number of resets of the hard-to- change factors. In this paper, unbalanced designs are considered for cases where the subplots are relatively expensive and the experimental apparatus accommodates an unequal number of runs per whole-plot. We provide construction methods for unbalanced second-order split- plot designs that possess the equivalence estimation optimality property, providing best linear unbiased estimates of the parameters; independent of the variance components. Unbalanced versions of the central composite and Box-Behnken designs are developed. For cases where the subplot cost approaches the whole-plot cost, minimal point designs are proposed and illustrated with a split-plot Notz design.

Scientific, statistical, practical, and regulatory considerations in design space development.

PubMed

Debevec, Veronika; Srčič, Stanko; Horvat, Matej

2018-03-01

The quality by design (QbD) paradigm guides the pharmaceutical industry towards improved understanding of products and processes, and at the same time facilitates a high degree of manufacturing and regulatory flexibility throughout the establishment of the design space. This review article presents scientific, statistical and regulatory considerations in design space development. All key development milestones, starting with planning, selection of factors, experimental execution, data analysis, model development and assessment, verification, and validation, and ending with design space submission, are presented and discussed. The focus is especially on frequently ignored topics, like management of factors and CQAs that will not be included in experimental design, evaluation of risk of failure on design space edges, or modeling scale-up strategy. Moreover, development of a design space that is independent of manufacturing scale is proposed as the preferred approach.

Human factor roles in design of teleoperator systems

NASA Technical Reports Server (NTRS)

Janow, C.; Malone, T. B.

1973-01-01

Teleoperator systems are considered, giving attention to types of teleoperators, a manned space vehicle attached manipulator, a free-flying teleoperator, a surface exploration roving vehicle, the human factors role in total system design, the manipulator system, the sensor system, the communication system, the control system, and the mobility system. The role of human factors in the development of teleoperator systems is also discussed, taking into account visual systems, an operator control station, and the manipulators.

A novel method for multifactorial bio-chemical experiments design based on combinational design theory.

PubMed

Wang, Xun; Sun, Beibei; Liu, Boyang; Fu, Yaping; Zheng, Pan

2017-01-01

Experimental design focuses on describing or explaining the multifactorial interactions that are hypothesized to reflect the variation. The design introduces conditions that may directly affect the variation, where particular conditions are purposely selected for observation. Combinatorial design theory deals with the existence, construction and properties of systems of finite sets whose arrangements satisfy generalized concepts of balance and/or symmetry. In this work, borrowing the concept of "balance" in combinatorial design theory, a novel method for multifactorial bio-chemical experiments design is proposed, where balanced templates in combinational design are used to select the conditions for observation. Balanced experimental data that covers all the influencing factors of experiments can be obtianed for further processing, such as training set for machine learning models. Finally, a software based on the proposed method is developed for designing experiments with covering influencing factors a certain number of times.

Design and analysis of sustainable paper bicycle

NASA Astrophysics Data System (ADS)

Roni Sahroni, Taufik; Nasution, Januar

2017-12-01

This paper presents the design of sustainable paper bicycle which describes the stage by stage in the production of paper bicycle. The objective of this project is to design a sustainable paper bicycles to be used for children under five years old. The design analysis emphasizes in screening method to ensure the design fulfil the safety purposes. The evaluation concept is presented in designing a sustainable paper bicycle to determine highest rating. Project methodology is proposed for developing a sustainable paper bicycle. Design analysis of pedal, front and rear wheel, seat, and handle were presented using AutoCAD software. The design optimization was performed to fulfil the safety factors by modifying the material size and dimension. Based on the design analysis results, it is found that the optimization results met the factor safety. As a result, a sustainable paper bicycle was proposed for children under five years old.

Spaceflight Human System Standards

NASA Technical Reports Server (NTRS)

Holubec, Keith; Tillman, Barry; Connolly, Jan

2009-01-01

NASA created a new approach for human system integration and human performance standards. NASA created two documents a standard and a reference handbook. The standard is titled NASA Space Flight Human-System Standard (SFHSS) and consists of two-volumes: Volume 1- Crew Health This volume covers standards needed to support astronaut health (medical care, nutrition, sleep, exercise, etc.) Volume 2 Human Factors, Habitability and Environmental Health This volume covers the standards for system design that will maintain astronaut performance (ie., environmental factors, design of facilities, layout of workstations, and lighting requirements). It includes classic human factors requirements. The new standards document is written in terms so that it is applicable to a broad range of present and future NASA systems. The document states that all new programs prepare system-specific requirements that will meet the general standards. For example, the new standard does not specify a design should accommodate specific percentiles of a defined population. Rather, NASA-STD-3001, Volume 2 states that all programs shall prepare program-specific requirements that define the user population and their size ranges. The design shall then accommodate the full size range of those users. The companion reference handbook, Human Integration Design Handbook (HIDH), was developed to capture the design consideration information from NASA-STD-3000, and adds spaceflight lessons learned, gaps in knowledge, example solutions, and suggests research to further mature specific disciplines. The HIDH serves two major purposes: HIDH is the reference document for writing human factors requirements for specific systems. HIDH contains design guidance information that helps insure that designers create systems which safely and effectively accommodate the capabilities and limitations of space flight crews.

How Learning Environments Can Stimulate Student Imagination

ERIC Educational Resources Information Center

Liang, Chaoyun; Hsu, Yuling; Huang, Yinghsiu; Chen, Sheng-Chih

2012-01-01

The purpose of this study was to investigate an array of environmental factors that can stimulate imagination and explore how these factors manifest in different design phases. The participants of this study were students in the field of educational technology from four universities across Taiwan. The instructional design process was divided into…

Association between Lifestyle and School Attendance in Japanese Medical Students: A Pilot Study

ERIC Educational Resources Information Center

Tanaka, Masaaki; Watanabe, Yasuyoshi

2012-01-01

Objective: Lifestyle factors are thought to be associated with students' academic performance. Whether lifestyle factors were associated with medical students' school attendance was determined. Design: Cross-sectional design. Setting: The study group consisted of 157 healthy second-year medical students attending Osaka City University Graduate…

Factors Affecting the Acceptability of Microforms as a Reading Medium.

ERIC Educational Resources Information Center

Spencer, Herbert; Reynolds, Linda

Based on visits to representative microform users and an extensive survey of relevant literature, a study was undertaken to assess the relative importance of factors affecting the acceptability of microforms as reading mediums. The following variables were considered: (1) microform characteristics; (2) equipment design; (3) work station design;…

Non-Linear Modeling of Growth Prerequisites in a Finnish Polytechnic Institution of Higher Education

ERIC Educational Resources Information Center

Nokelainen, Petri; Ruohotie, Pekka

2009-01-01

Purpose: This study aims to examine the factors of growth-oriented atmosphere in a Finnish polytechnic institution of higher education with categorical exploratory factor analysis, multidimensional scaling and Bayesian unsupervised model-based visualization. Design/methodology/approach: This study was designed to examine employee perceptions of…

Mistreatment in Assisted Living Facilities: Complaints, Substantiations, and Risk Factors

ERIC Educational Resources Information Center

Phillips, Linda R.; Guo, Guifang

2011-01-01

Purpose of the Study: Use archived public data from Arizona to explore relationships among selected institutional and resident risk and situation-specific factors and complaints and substantiated allegations of various types of mistreatment in assisted living facilities (ALFs). Design and Methods: An exploratory/descriptive 2-group design was…

Discovery of novel aminobenzisoxazole derivatives as orally available factor IXa inhibitors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sakurada, Isao; Endo, Toshiya; Hikita, Katsuyoshi

2017-06-01

Using structure based drug design, novel aminobenzisoxazoles as coagulation factor IXa inhibitors were designed and synthesized. Highly selective inhibition of FIXa over FXa was demonstrated. Anticoagulation profile of selected compounds was evaluated by aPTT and PT tests. In vitro ADMET and pharmacokinetic (PK) profiles were also evaluated.

Factors Influencing Teachers' Engagement in Informal Learning Activities

ERIC Educational Resources Information Center

Lohman, Margaret C.

2006-01-01

Purpose: The purpose of this study is to examine factors influencing the engagement of public school teachers in informal learning activities. Design/methodology/approach: This study used a survey research design. Findings: Analysis of the data found that teachers rely to a greater degree on interactive than on independent informal learning…

Space Station Human Factors Research Review. Volume 4: Inhouse Advanced Development and Research

NASA Technical Reports Server (NTRS)

Tanner, Trieve (Editor); Clearwater, Yvonne A. (Editor); Cohen, Marc M. (Editor)

1988-01-01

A variety of human factors studies related to space station design are presented. Subjects include proximity operations and window design, spatial perceptual issues regarding displays, image management, workload research, spatial cognition, virtual interface, fault diagnosis in orbital refueling, and error tolerance and procedure aids.

Factors Influencing Residents' Satisfaction in Residential Aged Care

ERIC Educational Resources Information Center

Chou, Shu-Chiung; Boldy, Duncan P.; Lee, Andy H.

2003-01-01

Purpose: The aim of this study was to identify the important factors influencing residents' satisfaction in residential aged care and to provide a better understanding of their interrelationships. Design and Methods: A cross-sectional survey design was used to collect the required information, including resident satisfaction, resident dependency…

Human factors considerations in the design and evaluation of electronic flight bags (EFBs) : version 2

DOT National Transportation Integrated Search

2003-09-01

Electronic Flight Bags (EFBs) are coming into the flight deck, bringing along with them a wide range of human factors considerations. In order to understand and assess the full impact of an EFB, designers and evaluators require an understanding of ho...

Human factors considerations in the design and evaluation of electronic flight bags (EFBs), version 1 : basic functions

DOT National Transportation Integrated Search

2003-09-01

Electronic Flight Bags (EFBs) are coming into the flight deck, bringing along with them a wide range of human factors considerations. In order to understand and assess the full impact of an EFB, designers and evaluators require an understanding of ho...

An investigation of the speeding-related crash designation through crash narrative reviews sampled via logistic regression.

PubMed

Fitzpatrick, Cole D; Rakasi, Saritha; Knodler, Michael A

2017-01-01

Speed is one of the most important factors in traffic safety as higher speeds are linked to increased crash risk and higher injury severities. Nearly a third of fatal crashes in the United States are designated as "speeding-related", which is defined as either "the driver behavior of exceeding the posted speed limit or driving too fast for conditions." While many studies have utilized the speeding-related designation in safety analyses, no studies have examined the underlying accuracy of this designation. Herein, we investigate the speeding-related crash designation through the development of a series of logistic regression models that were derived from the established speeding-related crash typologies and validated using a blind review, by multiple researchers, of 604 crash narratives. The developed logistic regression model accurately identified crashes which were not originally designated as speeding-related but had crash narratives that suggested speeding as a causative factor. Only 53.4% of crashes designated as speeding-related contained narratives which described speeding as a causative factor. Further investigation of these crashes revealed that the driver contributing code (DCC) of "driving too fast for conditions" was being used in three separate situations. Additionally, this DCC was also incorrectly used when "exceeding the posted speed limit" would likely have been a more appropriate designation. Finally, it was determined that the responding officer only utilized one DCC in 82% of crashes not designated as speeding-related but contained a narrative indicating speed as a contributing causal factor. The use of logistic regression models based upon speeding-related crash typologies offers a promising method by which all possible speeding-related crashes could be identified. Published by Elsevier Ltd.

Resolution V fractional factorial design for screening of factors affecting weakly basic drugs liposomal systems.

PubMed

Nageeb El-Helaly, Sara; Habib, Basant A; Abd El-Rahman, Mohamed K

2018-07-01

This study aims to investigate factors affecting weakly basic drugs liposomal systems. Resolution V fractional factorial design (2 V 5-1 ) is used as an example of screening designs that would better be used as a wise step before proceeding with detailed factors effects or optimization studies. Five factors probable to affect liposomal systems of weakly basic drugs were investigated using Amisulpride as a model drug. Factors studied were; A: Preparation technique B: Phosphatidyl choline (PhC) amount (mg) C: Cholesterol: PhC molar ratio, D: Hydration volume (ml) and E: Sonication type. Levels investigated were; Ammonium sulphate-pH gradient technique or Transmembrane zinc chelation-pH gradient technique, 200 or 400 mg, 0 or 0.5, 10 or 20 ml and bath or probe sonication for A, B, C, D and E respectively. Responses measured were Particle size (PS) (nm), Zeta potential (ZP) (mV) and Entrapment efficiency percent (EE%). Ion selective electrode was used as a novel method for measuring unentrapped drug concentration and calculating entrapment efficiency without the need for liposomal separation. Factors mainly affecting the studied responses were Cholesterol: PhC ratio and hydration volume for PS, preparation technique for ZP and preparation technique and hydration volume for EE%. The applied 2 V 5-1 design enabled the use of only 16 trial combinations for screening the influence of five factors on weakly basic drugs liposomal systems. This clarifies the value of the use of screening experiments before extensive investigation of certain factors in detailed optimization studies. Copyright © 2018 Elsevier B.V. All rights reserved.

How system designers think: a study of design thinking in human factors engineering.

PubMed

Papantonopoulos, Sotiris

2004-11-01

The paper presents a descriptive study of design thinking in human factors engineering. The objective of the study is to analyse the role of interpretation in design thinking and the role of design practice in guiding interpretation. The study involved 10 system designers undertaking the allocation of cognitive functions in three production planning and control task scenarios. Allocation decisions were recorded and verbal protocols of the design process were collected to elicit the subjects' thought processes. Verbal protocol analysis showed that subjects carried out the design of cognitive task allocation as a problem of applying a selected automation technology from their initial design deliberations. This design strategy stands in contrast to the predominant view of system design that stipulates that user requirements should be thoroughly analysed prior to making any decisions about technology. Theoretical frameworks from design research and ontological design showed that the system design process may be better understood by recognizing the role of design hypotheses in system design, as well as the diverse interactions between interpretation and practice, means and ends, and design practice and the designer's pre-understanding which shape the design process. Ways to balance the bias exerted on the design process were discussed.

Participatory ergonomics for psychological factors evaluation in work system design.

PubMed

Wang, Lingyan; Lau, Henry Y K

2012-01-01

It is a well recognized understanding that workers whose voice needs to be heard should be actively encouraged as full participants and involved in the early design stages of new ergonomic work system which encompass the development and implementation of new tools, workplaces, technologies or organizations. This paper presents a novel participatory strategy to evaluate three key psychological factors which are respectively mental fatigue, spiritual stress, and emotional satisfaction in work system design based on a modified version of Participatory Ergonomics (PE). In specific, it integrates a PE technique with a formulation view by combining the parallel development of PE strategies, frameworks and functions throughout the coverage of the entire work system design process, so as to bridge the gap between qualitative and quantitative analysis of psychological factors which can cause adverse or advantageous effects on worker's physiological and behavioral performance.

Application of uniform design to improve dental implant system.

PubMed

Cheng, Yung-Chang; Lin, Deng-Huei; Jiang, Cho-Pei

2015-01-01

This paper introduces the application of uniform experimental design to improve dental implant systems subjected to dynamic loads. The dynamic micromotion of the Zimmer dental implant system is calculated and illustrated by explicit dynamic finite element analysis. Endogenous and exogenous factors influence the success rate of dental implant systems. Endogenous factors include: bone density, cortical bone thickness and osseointegration. Exogenous factors include: thread pitch, thread depth, diameter of implant neck and body size. A dental implant system with a crest module was selected to simulate micromotion distribution and stress behavior under dynamic loads using conventional and proposed methods. Finally, the design which caused minimum micromotion was chosen as the optimal design model. The micromotion of the improved model is 36.42 μm, with an improvement is 15.34% as compared to the original model.

Human factor implications of the Eurocopter AS332L-1 Super Puma cockpit

NASA Technical Reports Server (NTRS)

Padfield, R. Randall

1993-01-01

The purpose of this paper is to identify and describe some of the human factor problems which can occur in the cockpit of a modern civilian helicopter. After examining specific hardware and software problems in the cockpit design of the Eurocopter (Aerospatiale) AS332L-1 Super Puma, the author proposes several principles that can be used to avoid similar human factors problems in the design of future cockpits. These principles relate to the use and function of warning lights, the design of autopilots in two-pilot aircraft, and the labeling of switches and warning lights, specifically with respect to abbreviations and translations from languages other than English. In the final section of the paper, the author describes current trends in society which he suggests should be taken into consideration when designing future aircraft cockpits.

The importance of operations, risk, and cost assessment to space transfer systems design

NASA Technical Reports Server (NTRS)

Ball, J. M.; Komerska, R. J.; Rowell, L. F.

1992-01-01

This paper examines several methodologies which contribute to comprehensive subsystem cost estimation. The example of a space-based lunar space transfer vehicle (STV) design is used to illustrate how including both primary and secondary factors into cost affects the decision of whether to use aerobraking or propulsion for earth orbit capture upon lunar return. The expected dominant cost factor in this decision is earth-to-orbit launch cost driven by STV mass. However, to quantify other significant cost factors, this cost comparison included a risk analysis to identify development and testing costs, a Taguchi design of experiments to determine a minimum mass aerobrake design, and a detailed operations analysis. As a result, the predicted cost advantage of aerobraking, while still positive, was subsequently reduced by about 30 percent compared to the simpler mass-based cost estimates.

Subscale and Full-Scale Testing of Buckling-Critical Launch Vehicle Shell Structures

NASA Technical Reports Server (NTRS)

Hilburger, Mark W.; Haynie, Waddy T.; Lovejoy, Andrew E.; Roberts, Michael G.; Norris, Jeffery P.; Waters, W. Allen; Herring, Helen M.

2012-01-01

New analysis-based shell buckling design factors (aka knockdown factors), along with associated design and analysis technologies, are being developed by NASA for the design of launch vehicle structures. Preliminary design studies indicate that implementation of these new knockdown factors can enable significant reductions in mass and mass-growth in these vehicles and can help mitigate some of NASA s launch vehicle development and performance risks by reducing the reliance on testing, providing high-fidelity estimates of structural performance, reliability, robustness, and enable increased payload capability. However, in order to validate any new analysis-based design data or methods, a series of carefully designed and executed structural tests are required at both the subscale and full-scale level. This paper describes recent buckling test efforts at NASA on two different orthogrid-stiffened metallic cylindrical shell test articles. One of the test articles was an 8-ft-diameter orthogrid-stiffened cylinder and was subjected to an axial compression load. The second test article was a 27.5-ft-diameter Space Shuttle External Tank-derived cylinder and was subjected to combined internal pressure and axial compression.

Selecting a proper design period for heliostat field layout optimization using Campo code

NASA Astrophysics Data System (ADS)

Saghafifar, Mohammad; Gadalla, Mohamed

2016-09-01

In this paper, different approaches are considered to calculate the cosine factor which is utilized in Campo code to expand the heliostat field layout and maximize its annual thermal output. Furthermore, three heliostat fields containing different number of mirrors are taken into consideration. Cosine factor is determined by considering instantaneous and time-average approaches. For instantaneous method, different design days and design hours are selected. For the time average method, daily time average, monthly time average, seasonally time average, and yearly time averaged cosine factor determinations are considered. Results indicate that instantaneous methods are more appropriate for small scale heliostat field optimization. Consequently, it is proposed to consider the design period as the second design variable to ensure the best outcome. For medium and large scale heliostat fields, selecting an appropriate design period is more important. Therefore, it is more reliable to select one of the recommended time average methods to optimize the field layout. Optimum annual weighted efficiency for heliostat fields (small, medium, and large) containing 350, 1460, and 3450 mirrors are 66.14%, 60.87%, and 54.04%, respectively.

Piloting Vertical Flight Aircraft: A Conference on Flying Qualities and Human Factors

NASA Technical Reports Server (NTRS)

Blanken, Christopher L. (Editor); Whalley, Matthew S. (Editor)

1993-01-01

This document contains papers from a specialists' meeting entitled 'Piloting Vertical Flight Aircraft: A Conference on Flying Qualities and Human Factors.' Vertical flight aircraft, including helicopters and a variety of Vertical Takeoff and Landing (VTOL) concepts, place unique requirements on human perception, control, and performance for the conduct of their design missions. The intent of this conference was to examine, for these vehicles, advances in: (1) design of flight control systems for ADS-33C standards; (2) assessment of human factors influences of cockpit displays and operational procedures; (3) development of VTOL design and operational criteria; and (4) development of theoretical methods or models for predicting pilot/vehicle performance and mission suitability. A secondary goal of the conference was to provide an initial venue for enhanced interaction between human factors and handling qualities specialists.

Participatory Design, User Involvement and Health IT Evaluation.

PubMed

Kushniruk, Andre; Nøhr, Christian

2016-01-01

End user involvement and input into the design and evaluation of information systems has been recognized as being a critical success factor in the adoption of information systems. Nowhere is this need more critical than in the design of health information systems. Consistent with evidence from the general software engineering literature, the degree of user input into design of complex systems has been identified as one of the most important factors in the success or failure of complex information systems. The participatory approach goes beyond user-centered design and co-operative design approaches to include end users as more active participants in design ideas and decision making. Proponents of participatory approaches argue for greater end user participation in both design and evaluative processes. Evidence regarding the effectiveness of increased user involvement in design is explored in this contribution in the context of health IT. The contribution will discuss several approaches to including users in design and evaluation. Challenges in IT evaluation during participatory design will be described and explored along with several case studies.

Engineering Technical Review Planning Briefing

NASA Technical Reports Server (NTRS)

Gardner, Terrie

2012-01-01

The general topics covered in the engineering technical planning briefing are 1) overviews of NASA, Marshall Space Flight Center (MSFC), and Engineering, 2) the NASA Systems Engineering(SE) Engine and its implementation , 3) the NASA Project Life Cycle, 4) MSFC Technical Management Branch Services in relation to the SE Engine and the Project Life Cycle , 5) Technical Reviews, 6) NASA Human Factor Design Guidance , and 7) the MSFC Human Factors Team. The engineering technical review portion of the presentation is the primary focus of the overall presentation and will address the definition of a design review, execution guidance, the essential stages of a technical review, and the overall review planning life cycle. Examples of a technical review plan content, review approaches, review schedules, and the review process will be provided and discussed. The human factors portion of the presentation will focus on the NASA guidance for human factors. Human factors definition, categories, design guidance, and human factor specialist roles will be addressed. In addition, the NASA Systems Engineering Engine description, definition, and application will be reviewed as background leading into the NASA Project Life Cycle Overview and technical review planning discussion.

Aviation occupant survival factors: an empirical study of the SQ006 accident.

PubMed

Chang, Yu-Hern; Yang, Hui-Hua

2010-03-01

We present an empirical study of Singapore Airline (SIA) flight SQ006 to illustrate the critical factors that influence airplane occupant survivability. The Fuzzy Delphi Method was used to identify and rank the survival factors that may reduce injury and fatality in potentially survivable accidents. This is the first attempt by a group from both the public and private sectors in Taiwan to focus on cabin-safety issues related to survival factors. We designed a comprehensive survey based on our discussions with aviation safety experts. We next designed an array of important cabin-safety dimensions and then investigated and selected the critical survival factors for each dimension. Our findings reveal important cabin safety and survivability information that should provide a valuable reference for developing and evaluating aviation safety programs. We also believe that the results will be practical for designing cabin-safety education material for air travelers. Finally, the major contribution of this research is that it has identified 47 critical factors that influence accident survivability; therefore, it may encourage improvements that will promote more successful cabin-safety management. Copyright 2009 Elsevier Ltd. All rights reserved.

Visualization tool for human-machine interface designers

NASA Astrophysics Data System (ADS)

Prevost, Michael P.; Banda, Carolyn P.

1991-06-01

As modern human-machine systems continue to grow in capabilities and complexity, system operators are faced with integrating and managing increased quantities of information. Since many information components are highly related to each other, optimizing the spatial and temporal aspects of presenting information to the operator has become a formidable task for the human-machine interface (HMI) designer. The authors describe a tool in an early stage of development, the Information Source Layout Editor (ISLE). This tool is to be used for information presentation design and analysis; it uses human factors guidelines to assist the HMI designer in the spatial layout of the information required by machine operators to perform their tasks effectively. These human factors guidelines address such areas as the functional and physical relatedness of information sources. By representing these relationships with metaphors such as spring tension, attractors, and repellers, the tool can help designers visualize the complex constraint space and interacting effects of moving displays to various alternate locations. The tool contains techniques for visualizing the relative 'goodness' of a configuration, as well as mechanisms such as optimization vectors to provide guidance toward a more optimal design. Also available is a rule-based design checker to determine compliance with selected human factors guidelines.

Concrete pavement mixture design and analysis (MDA) : factors influencing drying shrinkage.

DOT National Transportation Integrated Search

2014-10-01

This literature review focuses on factors influencing drying shrinkage of concrete. Although the factors are normally interrelated, they : can be categorized into three groups: paste quantity, paste quality, and other factors.

The development and application of a multi-criteria optimization method to the design of a 20-seat regional jet airliner

NASA Astrophysics Data System (ADS)

Au, How Meng

The aircraft design process traditionally starts with a given set of top-level requirements. These requirements can be aircraft performance related such as the fuel consumption, cruise speed, or takeoff field length, etc., or aircraft geometry related such as the cabin height or cabin volume, etc. This thesis proposes a new aircraft design process in which some of the top-level requirements are not explicitly specified. Instead, these previously specified parameters are now determined through the use of the Price-Per-Value-Factor (PPVF) index. This design process is well suited for design projects where general consensus of the top-level requirements does not exist. One example is the design of small commuter airliners. The above mentioned value factor is comprised of productivity, cabin volume, cabin height, cabin pressurization, mission fuel consumption, and field length, each weighted to a different exponent. The relative magnitude and positive/negative signs of these exponents are in agreement with general experience. The value factors of the commuter aircraft are shown to have improved over a period of four decades. In addition, the purchase price is shown to vary linearly with the value factor. The initial aircraft sizing process can be manpower intensive if the calculations are done manually. By incorporating automation into the process, the design cycle can be shortened considerably. The Fortran program functions and subroutines in this dissertation, in addition to the design and optimization methodologies described above, contribute to the reduction of manpower required for the initial sizing process. By combining the new design process mentioned above and the PPVF as the objective function, an optimization study is conducted on the design of a 20-seat regional jet. Handbook methods for aircraft design are written into a Fortran code. A genetic algorithm is used as the optimization scheme. The result of the optimization shows that aircraft designed to this PPVF index can be competitive compared to existing turboprop commuter aircraft. The process developed can be applied to other classes of aircraft with the designer modifying the cost function based upon the design goals.

Universal Design: Process, Principles, and Applications

ERIC Educational Resources Information Center

Burgstahler, Sheryl

2009-01-01

Designing any product or environment involves the consideration of many factors, including aesthetics, engineering options, environmental issues, safety concerns, industry standards, and cost. Typically, designers focus their attention on the average user. In contrast, universal design (UD), according to the Center for Universal Design," is…

Effect of a workplace design and training intervention on individual performance, group effectiveness and collaboration: the role of environmental control.

PubMed

Robertson, Michelle M; Huang, Yueng-Hsiang

2006-01-01

The effects of a workplace design and training intervention and the relationships between perceived satisfaction of office workplace design factors (layout and storage) and work performance measures (individual performance, group collaboration and effectiveness) were studied with 120 office workers using the Workplace Environment Questionnaire. Further, we examined whether environmental control had a direct effect on work performance, and then explored whether environmental control mediated or moderated the relationship between workplace design factors and work performance. Results showed a significant, positive impact of the intervention on environmental satisfaction for workstation layout. Satisfaction with workstation layout had a significant relationship with individual performance, group collaboration and effectiveness; and satisfaction with workstation storage had a significant relationship with individual performance and group collaboration. Environmental control had a direct impact on individual performance and group collaboration; whereas, the mediating and moderating effects of environmental control on the relationship between workplace design factors and outcome variables were not significant.

Working memory and the design of health materials: a cognitive factors perspective.

PubMed

Wilson, Elizabeth A H; Wolf, Michael S

2009-03-01

Working memory and other supportive cognitive processes involved in learning are reviewed in the context of developing patient education materials. We specifically focus on the impact of certain design factors such as text format and syntax, the inclusion of images, and the choice of modality on individuals' ability to understand and remember health information. A selective review of relevant cognitive and learning theories is discussed with regard to their potential impact on the optimal design of health materials. Working memory is measured as an individual's capacity to hold and manipulate information in active consciousness. It is limited by necessity, and well-designed health materials can effectively minimize extraneous cognitive demands placed on individuals, making working memory resources more available to better process content-related information. Further research is needed to evaluate specific design principles and identify ideal uses of print versus video-based forms of communication for conveying information. The process of developing health materials should account for the cognitive demands that extrinsic factors such as modality place on patients.

Pros and Cons of the Interpenetrating Panel Design

Treesearch

Paul C. Van Deusen

2000-01-01

The interpenetrating sample design has been selected for the USDA Forest Service's Annual Forest Inventory System. The advantages and disadvantages of this design are discussed by considering alternatives such as the formerly used periodic design, a concentrated grid design, and disturbance based sampling. Factors considered for each design include fulfilling 1998...

Conceptual design and analysis of a dynamic scale model of the Space Station Freedom

NASA Technical Reports Server (NTRS)

Davis, D. A.; Gronet, M. J.; Tan, M. K.; Thorne, J.

1994-01-01

This report documents the conceptual design study performed to evaluate design options for a subscale dynamic test model which could be used to investigate the expected on-orbit structural dynamic characteristics of the Space Station Freedom early build configurations. The baseline option was a 'near-replica' model of the SSF SC-7 pre-integrated truss configuration. The approach used to develop conceptual design options involved three sets of studies: evaluation of the full-scale design and analysis databases, conducting scale factor trade studies, and performing design sensitivity studies. The scale factor trade study was conducted to develop a fundamental understanding of the key scaling parameters that drive design, performance and cost of a SSF dynamic scale model. Four scale model options were estimated: 1/4, 1/5, 1/7, and 1/10 scale. Prototype hardware was fabricated to assess producibility issues. Based on the results of the study, a 1/4-scale size is recommended based on the increased model fidelity associated with a larger scale factor. A design sensitivity study was performed to identify critical hardware component properties that drive dynamic performance. A total of 118 component properties were identified which require high-fidelity replication. Lower fidelity dynamic similarity scaling can be used for non-critical components.

Design Guidelines and Criteria for User/Operator Transactions with Battlefield Automated Systems. Volume I. Executive Summary

DTIC Science & Technology

1981-02-01

SUMMARY Robert N. Parrish, Jesse L. Gates, and Sarah J. Munger SYNECTICS CORPORATION HUMAN FACTORS TECHNICAL AREA L.. .iU. S. Army Research Institute for...of the Human Factors Technical Area, ARI, is the Contracting Officer’s Representative (COR) for this project. 19. KEY WORDS (Continue on reverse...aide It neceeary ad Identify by block number) Battlefield automated systems Human -computer interaction Design criteria System analysis Design guidelines

Evaluating the Properties of Poly(lactic-co-glycolic acid) Nanoparticle Formulations Encapsulating a Hydrophobic Drug by Using the Quality by Design Approach.

PubMed

Kozaki, Masato; Kobayashi, Shin-Ichiro; Goda, Yukihiro; Okuda, Haruhiro; Sakai-Kato, Kumiko

2017-01-01

We applied the Quality by Design (QbD) approach to the development of poly(lactic-co-glycolic acid) (PLGA) nanoparticle formulations encapsulating triamcinolone acetonide, and the critical process parameters (CPPs) were identified to clarify the correlations between critical quality attributes and CPPs. Quality risk management was performed by using an Ishikawa diagram and experiments with a fractional factorial design (ANOVA). The CPPs for particle size were PLGA concentration and rotation speed, and the CPP for relative drug loading efficiency was the poor solvent to good solvent volume ratio. By assessing the mutually related factors in the form of ratios, many factors could be efficiently considered in the risk assessment. We found a two-factor interaction between rotation speed and rate of addition of good solvent by using a fractional factorial design with resolution V. The system was then extended by using a central composite design, and the results obtained were visualized by using the response surface method to construct a design space. Our research represents a case study of the application of the QbD approach to pharmaceutical development, including formulation screening, by taking actual production factors into consideration. Our findings support the feasibility of using a similar approach to nanoparticle formulations under development. We could establish an efficient method of analyzing the CPPs of PLGA nanoparticles by using a QbD approach.

An Empirically Derived Taxonomy of Factors Affecting Physicians' Willingness to Disclose Medical Errors

PubMed Central

Kaldjian, Lauris C; Jones, Elizabeth W; Rosenthal, Gary E; Tripp-Reimer, Toni; Hillis, Stephen L

2006-01-01

BACKGROUND Physician disclosure of medical errors to institutions, patients, and colleagues is important for patient safety, patient care, and professional education. However, the variables that may facilitate or impede disclosure are diverse and lack conceptual organization. OBJECTIVE To develop an empirically derived, comprehensive taxonomy of factors that affects voluntary disclosure of errors by physicians. DESIGN A mixed-methods study using qualitative data collection (structured literature search and exploratory focus groups), quantitative data transformation (sorting and hierarchical cluster analysis), and validation procedures (confirmatory focus groups and expert review). RESULTS Full-text review of 316 articles identified 91 impeding or facilitating factors affecting physicians' willingness to disclose errors. Exploratory focus groups identified an additional 27 factors. Sorting and hierarchical cluster analysis organized factors into 8 domains. Confirmatory focus groups and expert review relocated 6 factors, removed 2 factors, and modified 4 domain names. The final taxonomy contained 4 domains of facilitating factors (responsibility to patient, responsibility to self, responsibility to profession, responsibility to community), and 4 domains of impeding factors (attitudinal barriers, uncertainties, helplessness, fears and anxieties). CONCLUSIONS A taxonomy of facilitating and impeding factors provides a conceptual framework for a complex field of variables that affects physicians' willingness to disclose errors to institutions, patients, and colleagues. This taxonomy can be used to guide the design of studies to measure the impact of different factors on disclosure, to assist in the design of error-reporting systems, and to inform educational interventions to promote the disclosure of errors to patients. PMID:16918739

Specifications for and preliminary design of a plant growth chamber for orbital experimental experiments

NASA Technical Reports Server (NTRS)

Sweet, H. C.; Simmonds, R. C.

1976-01-01

It was proposed that plant experiments be performed on board the space shuttle. To permit the proper execution of most tests, the craft must contain a plant growth chamber which is adequately designed to control those environmental factors which can induce changes in a plant's physiology and morphology. The various needs of, and environmental factors affecting, plants are identified. The permissilbe design, construction and performance limits for a plant-growth chamber are set, and tentative designs were prepared for units which are compatible with both the botanical requirements and the constraints imposed by the space shuttle.

Human performance models for computer-aided engineering

NASA Technical Reports Server (NTRS)

Elkind, Jerome I. (Editor); Card, Stuart K. (Editor); Hochberg, Julian (Editor); Huey, Beverly Messick (Editor)

1989-01-01

This report discusses a topic important to the field of computational human factors: models of human performance and their use in computer-based engineering facilities for the design of complex systems. It focuses on a particular human factors design problem -- the design of cockpit systems for advanced helicopters -- and on a particular aspect of human performance -- vision and related cognitive functions. By focusing in this way, the authors were able to address the selected topics in some depth and develop findings and recommendations that they believe have application to many other aspects of human performance and to other design domains.

Maximize, minimize or target - optimization for a fitted response from a designed experiment

DOE PAGES

Anderson-Cook, Christine Michaela; Cao, Yongtao; Lu, Lu

2016-04-01

One of the common goals of running and analyzing a designed experiment is to find a location in the design space that optimizes the response of interest. Depending on the goal of the experiment, we may seek to maximize or minimize the response, or set the process to hit a particular target value. After the designed experiment, a response model is fitted and the optimal settings of the input factors are obtained based on the estimated response model. Furthermore, the suggested optimal settings of the input factors are then used in the production environment.

A voyage to Mars: A challenge to collaboration between man and machines

NASA Technical Reports Server (NTRS)

Statler, Irving C.

1991-01-01

A speech addressing the design of man machine systems for exploration of space beyond Earth orbit from the human factors perspective is presented. Concerns relative to the design of automated and intelligent systems for the NASA Space Exploration Initiative (SEI) missions are largely based on experiences with integrating humans and comparable systems in aviation. The history, present status, and future prospect, of human factors in machine design are discussed in relation to a manned voyage to Mars. Three different cases for design philosophy are presented. The use of simulation is discussed. Recommendations for required research are given.

Cold-air investigation of a 31/2-stage fan-drive turbine with a stage loading factor of 4 designed for an integral lift engine. 2: Performance of 2-, 3- and 3 1/2-stage configurations

NASA Technical Reports Server (NTRS)

Whitney, W. J.

1977-01-01

The stage work distribution among the three stages was very close to the design value. The specific work output-mass flow characteristics of the three stages were closely matched. The efficiency of the 3 1/2 stage turbine at design specific work output and design speed was within 0.008 of the estimated value, and this agreement was felt to demonstrate the adequacy of the prediction method in the high stage loading factor regime.

Human Factors and the International Space Station

NASA Technical Reports Server (NTRS)

Peacock, Brian; Rajulu, Sudhakar; Novak, Jennifer; Rathjen, Thomas; Whitmore, Mihriban; Maida, James; Woolford, Barbara

2001-01-01

The purposes of this panel are to inform the human factors community regarding the challenges of designing the International Space Station (ISS) and to stimulate the broader human factors community into participating in the various basic and applied research opportunities associated with the ISS. This panel describes the variety of techniques used to plan and evaluate human factors for living and working in space. The panel members have contributed to many different aspects of the ISS design and operations. Architecture, equipment, and human physical performance requirements for various tasks have all been tailored to the requirements of operating in microgravity.

Design Process Improvement for Electric CAR Harness

NASA Astrophysics Data System (ADS)

Sawatdee, Thiwarat; Chutima, Parames

2017-06-01

In an automobile parts design company, the customer satisfaction is one of the most important factors for product design. Therefore, the company employs all means to focus its product design process based on the various requirements of customers resulting in high number of design changes. The objective of this research is to improve the design process of the electric car harness that effects the production scheduling by using Fault Tree Analysis (FTA) and Failure Mode and Effect Analysis (FMEA) as the main tools. FTA is employed for root cause analysis and FMEA is used to ranking a High Risk Priority Number (RPN) which is shows the priority of factors in the electric car harness that have high impact to the design of the electric car harness. After the implementation, the improvements are realized significantly since the number of design change is reduced from 0.26% to 0.08%.

Cold air investigation of 4 1/2-stage turbine with stage loading factor of 4.66 and high specific work output. 1: Overall performance

NASA Technical Reports Server (NTRS)

Whitney, W. J.; Behning, F. P.; Moffitt, T. P.; Hotz, G. M.

1977-01-01

The turbine developed design specific work output at design speed at a total pressure ratio of 6.745 with a corresponding efficiency of 0.855. The efficiency (0.855)was 3.1 points lower than the estimated efficiency quoted by the contractor in the design report and 0.7 of a point lower than that determined by a reference prediction method. The performance of the turbine, which was a forced vortex design, agreed with the performance determined by the prediction method to about the same extent as did the performance of three reference high stage loading factor turbines, which were free vortex designs.

Workforce Diversity: Monitoring Employment Trends in Public Organizations.

ERIC Educational Resources Information Center

Guajardo, Salomon A.

1999-01-01

Presents the use of research designs that can be used by human resource specialists to evaluate and monitor work force diversity and minority employment. Compares results of Repeated Measure Analyses of Variance with One Within-subjects Factor design with Repeated Measure Analyses of Variance with One Within-subjects Factor by job category. (JOW)

The Five-Factor Model Personality Assessment for Improved Student Design Team Performance

ERIC Educational Resources Information Center

Ogot, Madara; Okudan, Gul E.

2006-01-01

Researchers have long noted the correlation of various personality traits and team performance. Studies relating aggregate team personality traits to team performance are scattered in the literature and may not always be relevant to engineering design teams. This paper synthesizes the results from applicable Five-Factor Model (FFM)-based…

Factor Structure of the Behavior Flexibility Rating Scale (BFRS)

ERIC Educational Resources Information Center

Pituch, Keenan A.; Green, Vanessa A.; Sigafoos, Jeff; Itchon, Jonathan; O'Reilly, Mark; Lancioni, Giulio E.; Didden, Robert

2007-01-01

The Behavior Flexibility Rating Scale (BFRS) is designed to assess insistence on sameness or lack of behavioral flexibility, which is often associated with autism and other developmental disabilities. This study was designed to assess the factor structure of this scale for a sample of 968 individuals with autism, Asperger's syndrome, and Down…

Designing propagation environments in forest and native plant nurseries

Treesearch

Thomas D. Landis

2013-01-01

Propagation environments are areas that have been modified for plant growth, and can be designed using the law of limiting factors. Identifying critical factors that are most limiting to optimal plant growth is helpful when developing both bareroot and container nurseries. Propagation environments can be categorized into minimally-controlled, semi-controlled, and fully...

Designing a Visual Factors-Based Screen Display Interface: The New Role of the Graphic Technologist.

ERIC Educational Resources Information Center

Faiola, Tony; DeBloois, Michael L.

1988-01-01

Discusses the role of the graphic technologist in preparing computer screen displays for interactive videodisc systems, and suggests screen design guidelines. Topics discussed include the grid system; typography; visual factors research; color; course mobility through branching and software menus; and a model of course integration. (22 references)…

Motivational Factors and Teachers Commitment in Public Secondary Schools in Mbale Municipality

ERIC Educational Resources Information Center

Olurotimi, Ogunlade Joseph; Asad, Kamonges Wahab; Abdulrauf, Abdulkadir

2015-01-01

The study investigated the influence of motivational factors on teachers' commitment in public Secondary School in Mbale Municipality. The study employed Cross-sectional survey design. The sampling technique used to select was simple random sampling technique. The instrument used to collect data was a self designed questionnaire. The data…

NASA-STD-3001, Space Flight Human-System Standard and the Human Integration Design Handbook

NASA Technical Reports Server (NTRS)

Whitmore, Mihriban; Boyer, Jennifer; Holubec, Keith

2012-01-01

NASA-STD-3001 Space Flight Human-System Standard Volume 1, Crew Health, Volume 2, Human Factors, Habitability and Environmental Health, and the Human Integration Design Handbook (HIDH) have replaced the Man-Systems Integration Standards (MSIS), NASA-STD-3000. For decades, NASA-STD-3000 was a significant contribution to human spaceflight programs and to human-systems integration. However, with research program and project results being realized, advances in technology, and the availability of new information in a variety of topic areas, the time had arrived to update this extensive suite of standards and design information. NASA-STD-3001, Volume 2 contains the Agency level standards from the human and environmental factors disciplines that ensure human spaceflight operations are performed safely, efficiently, and effectively. The HIDH is organized in the same sequence and serves as the companion document to NASA-STD-3001, Volume 2, providing a compendium of human spaceflight history and knowledge. The HIDH is intended to aid interpretation of NASA-STD-3001, Volume 2 standards and to provide guidance for requirement writers and vehicle and habitat designers. Keywords Human Factors, Standards, Environmental Factors, NASA

Human Factors Considerations for Area Navigation Departure and Arrival Procedures

NASA Technical Reports Server (NTRS)

Barhydt, Richard; Adams, Catherine A.

2006-01-01

Area navigation (RNAV) procedures are being implemented in the United States and around the world as part of a transition to a performance-based navigation system. These procedures are providing significant benefits and have also caused some human factors issues to emerge. Under sponsorship from the Federal Aviation Administration (FAA), the National Aeronautics and Space Administration (NASA) has undertaken a project to document RNAV-related human factors issues and propose areas for further consideration. The component focusing on RNAV Departure and Arrival Procedures involved discussions with expert users, a literature review, and a focused review of the NASA Aviation Safety Reporting System (ASRS) database. Issues were found to include aspects of air traffic control and airline procedures, aircraft systems, and procedure design. Major findings suggest the need for specific instrument procedure design guidelines that consider the effects of human performance. Ongoing industry and government activities to address air-ground communication terminology, design improvements, and chart-database commonality are strongly encouraged. A review of factors contributing to RNAV in-service errors would likely lead to improved system design and operational performance.

Robust controller design for flexible structures using normalized coprime factor plant descriptions

NASA Technical Reports Server (NTRS)

Armstrong, Ernest S.

1993-01-01

Stabilization is a fundamental requirement in the design of feedback compensators for flexible structures. The search for the largest neighborhood around a given design plant for which a single controller produces closed-loop stability can be formulated as an H(sub infinity) control problem. The use of normalized coprime factor plant descriptions, in which the plant perturbations are defined as additive modifications to the coprime factors, leads to a closed-form expression for the maximum neighborhood boundary allowing optimal and suboptimal H(sub infinity) compensators to be computed directly without the usual gamma iteration. A summary of the theory on robust stabilization using normalized coprime factor plant descriptions is presented, and the application of the theory to the computation of robustly stable compensators for the phase version of the Control-Structures Interaction (CSI) Evolutionary Model is described. Results from the application indicate that the suboptimal version of the theory has the potential of providing the bases for the computation of low-authority compensators that are robustly stable to expected variations in design model parameters and additive unmodeled dynamics.

Lunar lander stage requirements based on the Civil Needs Data Base

NASA Technical Reports Server (NTRS)

Mulqueen, John A.

1992-01-01

This paper examines the lunar lander stages that will be necessary for the future exploration and development of the Moon. Lunar lander stage sizing is discussed based on the projected lunar payloads listed in the Civil Needs Data Base. Factors that will influence the lander stage design are identified and discussed. Some of these factors are (1) lunar orbiting and lunar surface lander bases; (2) implications of direct landing trajectories and landing from a parking orbit; (3) implications of landing site and parking orbit; (4) implications of landing site and parking orbit selection; (5) the use of expendable and reusable lander stages; and (6) the descent/ascent trajectories. Data relating the lunar lander stage design requirements to each of the above factors and others are presented in parametric form. These data will provide useful design data that will be applicable to future mission model modifications and design studies.

Morphology of Design of Aerospace Systems with Inclusion of Human Factors

DTIC Science & Technology

1977-08-01

Alternatives," AFHRL-TR-71-52, AD-741 766. Wright- Patterson AFB, OH: Advanced Systems Division, Air Force Human Resources Iaboratory; December 1971. 3...Askren, W.B., "Human Resources and Personnel Cost Deta in System Design Tradeoffs," AFHRL-TR-73-46, AD-770 737, Wright- Patterson AFB, OH: Advanced...Studies," Human Factors, February 1975, 17(0), pp. 4-12. 5 Askren, W.B., "Human Resources as Engineering Design Criteria," AFHRL-TR-76-1, Wright- Patterson

Human Factors Engineering. Part 2. HEDGE (Human Factors Engineering Data Guide for Evaluation)

DTIC Science & Technology

1983-11-30

Use.Condit ions 0 7ý est Item ComoentsTask Categories EPurposes 2 ;c . INDEX TO THE INDEX MAN/ITEM TASK SHEET DETAILED DESIGN CONSIDERATION The purpose of...The use of these materials, in addition to standard Task and Design Checklists and Questionnaires, will enable you to tailor your FIFE subtest to a...specific Con item. The These materials have been prepared especially for you: I. They are intended to support test engineers not design engineers. 2

Human factors dimensions in the evolution of increasingly automated control rooms for near-earth satellites

NASA Technical Reports Server (NTRS)

Mitchell, C. M.

1982-01-01

The NASA-Goddard Space Flight Center is responsible for the control and ground support for all of NASA's unmanned near-earth satellites. Traditionally, each satellite had its own dedicated mission operations room. In the mid-seventies, an integration of some of these dedicated facilities was begun with the primary objective to reduce costs. In this connection, the Multi-Satellite Operations Control Center (MSOCC) was designed. MSOCC represents currently a labor intensive operation. Recently, Goddard has become increasingly aware of human factors and human-machine interface issues. A summary is provided of some of the attempts to apply human factors considerations in the design of command and control environments. Current and future activities with respect to human factors and systems design are discussed, giving attention to the allocation of tasks between human and computer, and the interface for the human-computer dialogue.

[Eco-epidemiology: towards epidemiology of complexity].

PubMed

Bizouarn, Philippe

2016-05-01

In order to solve public health problems posed by the epidemiology of risk factors centered on the individual and neglecting the causal processes linking the risk factors with the health outcomes, Mervyn Susser proposed a multilevel epidemiology called eco-epidemiology, addressing the interdependence of individuals and their connection with molecular, individual, societal, environmental levels of organization participating in the causal disease processes. The aim of this epidemiology is to integrate more than a level of organization in design, analysis and interpretation of health problems. After presenting the main criticisms of risk-factor epidemiology focused on the individual, we will try to show how eco-epidemiology and its development could help to understand the need for a broader and integrative epidemiology, in which studies designed to identify risk factors would be balanced by studies designed to answer other questions equally vital to public health. © 2016 médecine/sciences – Inserm.

[Optimization of Polysaccharide Extraction from Spirodela polyrrhiza by Plackett-Burman Design Combined with Box-Behnken Response Surface Methodology].

PubMed

Jiang, Zheng; Wang, Hong; Wu, Qi-nan

2015-06-01

To optimize the processing of polysaccharide extraction from Spirodela polyrrhiza. Five factors related to extraction rate of polysaccharide were optimized by the Plackett-Burman design. Based on this study, three factors, including alcohol volume fraction, extraction temperature and ratio of material to liquid, were regarded as investigation factors by Box-Behnken response surface methodology. The effect order of three factors on the extraction rate of polysaccharide from Spirodela polyrrhiza were as follows: extraction temperature, alcohol volume fraction,ratio of material to liquid. According to Box-Behnken response, the best extraction conditions were: alcohol volume fraction of 81%, ratio of material to liquid of 1:42, extraction temperature of 100 degrees C, extraction time of 60 min for four times. Plackett-Burman design and Box-Behnken response surface methodology used to optimize the extraction process for the polysaccharide in this study is effective and stable.

Reliability Estimating Procedures for Electric and Thermochemical Propulsion Systems. Volume 2

DTIC Science & Technology

1977-02-01

final form. For some components, the parameters are calculated from design factors (e.g., design life) that must be input when requested. Each component...Components Components are regarded as statis- tically identical if they are drawn from the same production lot because the initial and sub- sequent...table yields b 0.0023 The - factors are obtained from Tables 2.2.4-1 through 2.2.4-5: Factor Value rE Space, flight 1 JANTXV quality 0.5 7A Small signal

Enhanced/Synthetic Vision Systems - Human factors research and implications for future systems

NASA Technical Reports Server (NTRS)

Foyle, David C.; Ahumada, Albert J.; Larimer, James; Sweet, Barbara T.

1992-01-01

This paper reviews recent human factors research studies conducted in the Aerospace Human Factors Research Division at NASA Ames Research Center related to the development and usage of Enhanced or Synthetic Vision Systems. Research discussed includes studies of field of view (FOV), representational differences of infrared (IR) imagery, head-up display (HUD) symbology, HUD advanced concept designs, sensor fusion, and sensor/database fusion and evaluation. Implications for the design and usage of Enhanced or Synthetic Vision Systems are discussed.

Universal Design in Postsecondary Education: Process, Principles, and Applications

ERIC Educational Resources Information Center

Burgstahler, Sheryl

2009-01-01

Designing any product or environment involves the consideration of many factors, including aesthetics, engineering options, environmental issues, safety concerns, industry standards, and cost. Typically, designers focus their attention on the average user. In contrast, universal design (UD), according to the Center for Universal Design, "is…

Musculoskeletal Problems in Iranian Hand-Woven Shoe-Sole Making Operation and Developing Guidelines for Workstation Design.

PubMed

Veisi, H; Choobineh, A R; Ghaem, H

2016-04-01

Musculoskeletal disorders (MSDs) are among important health problems in working population. Because of performing difficult physical activities, hand-woven shoe-sole makers are at risk of developing various types of MSDs. To determine the prevalence of musculoskeletal symptoms in different body areas of hand-woven shoe-sole makers, assess workers' postures and workstations, evaluate ergonomic and individual factors associated with MSDs, and develop guidelines for designing hand-woven shoe-sole making workstation. In this cross-sectional study, the prevalence of MSDs symptoms and their risk factors were studied among 240 hand-woven shoe-sole makers. Working posture and workstations were ergonomically assessed as well. The data were collected through interviewing and using Nordic musculoskeletal questionnaire and by direct observation of posture using RULA method. Logistic regression analysis was used to determine risk factors associated with MSDs symptoms. The prevalence and severity of MSDs symptoms were high among the study population. Ergonomic factors including daily working time, working posture, and force exertion, as well as individual factors, such as age, job tenure, and education were significantly associated with MSDs symptoms. It seems that the majority of ergonomics shortcomings originate from poorly designed workstation. Some general guidelines for designing shoe-sole making workstation are presented.

Sociotechnical attributes of safe and unsafe work systems

PubMed Central

Kleiner, Brian M.; Hettinger, Lawrence J.; DeJoy, David M.; Huang, Yuang-Hsiang; Love, Peter E.D.

2015-01-01

Theoretical and practical approaches to safety based on sociotechnical systems principles place heavy emphasis on the intersections between social–organisational and technical–work process factors. Within this perspective, work system design emphasises factors such as the joint optimisation of social and technical processes, a focus on reliable human–system performance and safety metrics as design and analysis criteria, the maintenance of a realistic and consistent set of safety objectives and policies, and regular access to the expertise and input of workers. We discuss three current approaches to the analysis and design of complex sociotechnical systems: human–systems integration, macroergonomics and safety climate. Each approach emphasises key sociotechnical systems themes, and each prescribes a more holistic perspective on work systems than do traditional theories and methods. We contrast these perspectives with historical precedents such as system safety and traditional human factors and ergonomics, and describe potential future directions for their application in research and practice. Practitioner Summary: The identification of factors that can reliably distinguish between safe and unsafe work systems is an important concern for ergonomists and other safety professionals. This paper presents a variety of sociotechnical systems perspectives on intersections between social–organisational and technology–work process factors as they impact work system analysis, design and operation. PMID:25909756

Anthropometric data reduction using confirmatory factor analysis.

PubMed

Rohani, Jafri Mohd; Olusegun, Akanbi Gabriel; Rani, Mat Rebi Abdul

2014-01-01

The unavailability of anthropometric data especially in developing countries has remained a limiting factor towards the design of learning facilities with sufficient ergonomic consideration. Attempts to use anthropometric data from developed countries have led to provision of school facilities unfit for the users. The purpose of this paper is to use factor analysis to investigate the suitability of the collected anthropometric data as a database for school design in Nigerian tertiary institutions. Anthropometric data were collected from 288 male students in a Federal Polytechnic in North-West of Nigeria. Their age is between 18-25 years. Nine vertical anthropometric dimensions related to heights were collected using the conventional traditional equipment. Exploratory factor analysis was used to categorize the variables into a model consisting of two factors. Thereafter, confirmatory factor analysis was used to investigate the fit of the data to the proposed model. A just identified model, made of two factors, each with three variables was developed. The variables within the model accounted for 81% of the total variation of the entire data. The model was found to demonstrate adequate validity and reliability. Various measuring indices were used to verify that the model fits the data properly. The final model reveals that stature height and eye height sitting were the most stable variables for designs that have to do with standing and sitting construct. The study has shown the application of factor analysis in anthropometric data analysis. The study highlighted the relevance of these statistical tools to investigate variability among anthropometric data involving diverse population, which has not been widely used for analyzing previous anthropometric data. The collected data is therefore suitable for use while designing for Nigerian students.

Applying human factors principles to alert design increases efficiency and reduces prescribing errors in a scenario-based simulation

PubMed Central

Russ, Alissa L; Zillich, Alan J; Melton, Brittany L; Russell, Scott A; Chen, Siying; Spina, Jeffrey R; Weiner, Michael; Johnson, Elizabette G; Daggy, Joanne K; McManus, M Sue; Hawsey, Jason M; Puleo, Anthony G; Doebbeling, Bradley N; Saleem, Jason J

2014-01-01

Objective To apply human factors engineering principles to improve alert interface design. We hypothesized that incorporating human factors principles into alerts would improve usability, reduce workload for prescribers, and reduce prescribing errors. Materials and methods We performed a scenario-based simulation study using a counterbalanced, crossover design with 20 Veterans Affairs prescribers to compare original versus redesigned alerts. We redesigned drug–allergy, drug–drug interaction, and drug–disease alerts based upon human factors principles. We assessed usability (learnability of redesign, efficiency, satisfaction, and usability errors), perceived workload, and prescribing errors. Results Although prescribers received no training on the design changes, prescribers were able to resolve redesigned alerts more efficiently (median (IQR): 56 (47) s) compared to the original alerts (85 (71) s; p=0.015). In addition, prescribers rated redesigned alerts significantly higher than original alerts across several dimensions of satisfaction. Redesigned alerts led to a modest but significant reduction in workload (p=0.042) and significantly reduced the number of prescribing errors per prescriber (median (range): 2 (1–5) compared to original alerts: 4 (1–7); p=0.024). Discussion Aspects of the redesigned alerts that likely contributed to better prescribing include design modifications that reduced usability-related errors, providing clinical data closer to the point of decision, and displaying alert text in a tabular format. Displaying alert text in a tabular format may help prescribers extract information quickly and thereby increase responsiveness to alerts. Conclusions This simulation study provides evidence that applying human factors design principles to medication alerts can improve usability and prescribing outcomes. PMID:24668841

Applying human factors principles to alert design increases efficiency and reduces prescribing errors in a scenario-based simulation.

PubMed

Russ, Alissa L; Zillich, Alan J; Melton, Brittany L; Russell, Scott A; Chen, Siying; Spina, Jeffrey R; Weiner, Michael; Johnson, Elizabette G; Daggy, Joanne K; McManus, M Sue; Hawsey, Jason M; Puleo, Anthony G; Doebbeling, Bradley N; Saleem, Jason J

2014-10-01

To apply human factors engineering principles to improve alert interface design. We hypothesized that incorporating human factors principles into alerts would improve usability, reduce workload for prescribers, and reduce prescribing errors. We performed a scenario-based simulation study using a counterbalanced, crossover design with 20 Veterans Affairs prescribers to compare original versus redesigned alerts. We redesigned drug-allergy, drug-drug interaction, and drug-disease alerts based upon human factors principles. We assessed usability (learnability of redesign, efficiency, satisfaction, and usability errors), perceived workload, and prescribing errors. Although prescribers received no training on the design changes, prescribers were able to resolve redesigned alerts more efficiently (median (IQR): 56 (47) s) compared to the original alerts (85 (71) s; p=0.015). In addition, prescribers rated redesigned alerts significantly higher than original alerts across several dimensions of satisfaction. Redesigned alerts led to a modest but significant reduction in workload (p=0.042) and significantly reduced the number of prescribing errors per prescriber (median (range): 2 (1-5) compared to original alerts: 4 (1-7); p=0.024). Aspects of the redesigned alerts that likely contributed to better prescribing include design modifications that reduced usability-related errors, providing clinical data closer to the point of decision, and displaying alert text in a tabular format. Displaying alert text in a tabular format may help prescribers extract information quickly and thereby increase responsiveness to alerts. This simulation study provides evidence that applying human factors design principles to medication alerts can improve usability and prescribing outcomes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Which intervention design factors influence performance of community health workers in low- and middle-income countries? A systematic review

PubMed Central

Kok, Maryse C; Dieleman, Marjolein; Taegtmeyer, Miriam; Broerse, Jacqueline EW; Kane, Sumit S; Ormel, Hermen; Tijm, Mandy M; de Koning, Korrie AM

2015-01-01

Community health workers (CHWs) are increasingly recognized as an integral component of the health workforce needed to achieve public health goals in low- and middle-income countries (LMICs). Many factors influence CHW performance. A systematic review was conducted to identify intervention design related factors influencing performance of CHWs. We systematically searched six databases for quantitative and qualitative studies that included CHWs working in promotional, preventive or curative primary health services in LMICs. One hundred and forty studies met the inclusion criteria, were quality assessed and double read to extract data relevant to the design of CHW programmes. A preliminary framework containing factors influencing CHW performance and characteristics of CHW performance (such as motivation and competencies) guided the literature search and review. A mix of financial and non-financial incentives, predictable for the CHWs, was found to be an effective strategy to enhance performance, especially of those CHWs with multiple tasks. Performance-based financial incentives sometimes resulted in neglect of unpaid tasks. Intervention designs which involved frequent supervision and continuous training led to better CHW performance in certain settings. Supervision and training were often mentioned as facilitating factors, but few studies tested which approach worked best or how these were best implemented. Embedment of CHWs in community and health systems was found to diminish workload and increase CHW credibility. Clearly defined CHW roles and introduction of clear processes for communication among different levels of the health system could strengthen CHW performance. When designing community-based health programmes, factors that increased CHW performance in comparable settings should be taken into account. Additional intervention research to develop a better evidence base for the most effective training and supervision mechanisms and qualitative research to inform policymakers in development of CHW interventions are needed. PMID:25500559

Development of Non-Optimum Factors for Launch Vehicle Propellant Tank Bulkhead Weight Estimation

NASA Technical Reports Server (NTRS)

Wu, K. Chauncey; Wallace, Matthew L.; Cerro, Jeffrey A.

2012-01-01

Non-optimum factors are used during aerospace conceptual and preliminary design to account for the increased weights of as-built structures due to future manufacturing and design details. Use of higher-fidelity non-optimum factors in these early stages of vehicle design can result in more accurate predictions of a concept s actual weights and performance. To help achieve this objective, non-optimum factors are calculated for the aluminum-alloy gores that compose the ogive and ellipsoidal bulkheads of the Space Shuttle Super-Lightweight Tank propellant tanks. Minimum values for actual gore skin thicknesses and weld land dimensions are extracted from selected production drawings, and are used to predict reference gore weights. These actual skin thicknesses are also compared to skin thicknesses predicted using classical structural mechanics and tank proof-test pressures. Both coarse and refined weights models are developed for the gores. The coarse model is based on the proof pressure-sized skin thicknesses, and the refined model uses the actual gore skin thicknesses and design detail dimensions. To determine the gore non-optimum factors, these reference weights are then compared to flight hardware weights reported in a mass properties database. When manufacturing tolerance weight estimates are taken into account, the gore non-optimum factors computed using the coarse weights model range from 1.28 to 2.76, with an average non-optimum factor of 1.90. Application of the refined weights model yields non-optimum factors between 1.00 and 1.50, with an average non-optimum factor of 1.14. To demonstrate their use, these calculated non-optimum factors are used to predict heavier, more realistic gore weights for a proposed heavy-lift launch vehicle s propellant tank bulkheads. These results indicate that relatively simple models can be developed to better estimate the actual weights of large structures for future launch vehicles.

The impact of human factors, crashworthiness and optical performance design requirements on helmet-mounted display development from the 1970s to the present

NASA Astrophysics Data System (ADS)

Harding, Thomas H.; Rash, Clarence E.; McLean, William E.; Martin, John S.

2015-05-01

Driven by the operational needs of modern warfare, the helmet-mounted display (HMD) has matured from a revolutionary, but impractical, World War I era idea for an infantry marksman's helmet-mounted weapon delivery system to a sophisticated and ubiquitous display and targeting system that dominates current night warfighting operations. One of the most demanding applications for HMD designs has been in Army rotary-wing aviation, where HMDs offer greater direct access to visual information and increased situational awareness in an operational environment where information availability is critical on a second-to-second basis. However, over the past 40 years of extensive HMD development, a myriad of crashworthiness, optical, and human factors issues have both frustrated and challenged designers. While it may be difficult to attain a full consensus on which are the most important HMD design factors, certainly head-supported weight (HSW), exit pupil size, field-of-view, image resolution and physical eye relief have been among the most critical. A confounding factor has been the interrelationship between the many design issues, such as early attempts to use non-glass optical elements to lower HSW, but at the cost of image quality, and hence, pilot visual performance. This paper traces how the role of the demanding performance requirements placed on HMDs by the U.S. Army aviation community has impacted the progress of HMD designs towards the Holy Grail of HMD design: a wide field-of-view, high resolution, binocular, full-color, totally crashworthy system.

On the application of motivation theory to human factors/ergonomics: motivational design principles for human-technology interaction.

PubMed

Szalma, James L

2014-12-01

Motivation is a driving force in human-technology interaction. This paper represents an effort to (a) describe a theoretical model of motivation in human technology interaction, (b) provide design principles and guidelines based on this theory, and (c) describe a sequence of steps for the. evaluation of motivational factors in human-technology interaction. Motivation theory has been relatively neglected in human factors/ergonomics (HF/E). In both research and practice, the (implicit) assumption has been that the operator is already motivated or that motivation is an organizational concern and beyond the purview of HF/E. However, technology can induce task-related boredom (e.g., automation) that can be stressful and also increase system vulnerability to performance failures. A theoretical model of motivation in human-technology interaction is proposed, based on extension of the self-determination theory of motivation to HF/E. This model provides the basis for both future research and for development of practical recommendations for design. General principles and guidelines for motivational design are described as well as a sequence of steps for the design process. Human motivation is an important concern for HF/E research and practice. Procedures in the design of both simple and complex technologies can, and should, include the evaluation of motivational characteristics of the task, interface, or system. In addition, researchers should investigate these factors in specific human-technology domains. The theory, principles, and guidelines described here can be incorporated into existing techniques for task analysis and for interface and system design.

A Quality by Experimental Design Approach to Assess the Effect of Formulation and Process Variables on the Extrusion and Spheronization of Drug-Loaded Pellets Containing Polyplasdone® XL-10.

PubMed

Saripella, Kalyan K; Loka, Nikhil C; Mallipeddi, Rama; Rane, Anuja M; Neau, Steven H

2016-04-01

Successful pellet production has been reported in literature with cross-linked poly(vinylpyrrolidone), Polyplasdone® XL-10 and INF-10. In the present study, a quality by experimental design approach was used to assess several formulation and process parameter effects on the characteristics of Polyplasdone® XL-10 pellets, including pellet size, shape, yield, usable yield, friability, and number of fines. The hypothesis is that design of experiments and appropriate data analysis allow optimization of the Polyplasdone product. High drug loading was achieved using caffeine, a moderately soluble drug to allow in vitro release studies. A five-factor, two-level, half-fractional factorial design (Resolution V) with center point batches allowed mathematical modeling of the influence of the factors and their two-factor interactions on five of the responses. The five factors were Polyplasdone® level in the powder blend, volume of water in the wet massing step, wet mixing time, spheronizer speed, and spheronization time. Each factor and/or its two-factor interaction with another factor influenced pellet characteristics. The behavior of these materials under various processing conditions and component levels during extrusion-spheronization have been assessed, discussed, and explained based on the results. Numerical optimization with a desirability of 0.974 was possible because curvature and lack of fit were not significant with any of the model equations. The values predicted by the optimization described well the observed responses. The hypothesis was thus supported.

Integration of the Response Surface Methodology with the Compromise Decision Support Problem in Developing a General Robust Design Procedure

NASA Technical Reports Server (NTRS)

Chen, Wei; Tsui, Kwok-Leung; Allen, Janet K.; Mistree, Farrokh

1994-01-01

In this paper we introduce a comprehensive and rigorous robust design procedure to overcome some limitations of the current approaches. A comprehensive approach is general enough to model the two major types of robust design applications, namely, robust design associated with the minimization of the deviation of performance caused by the deviation of noise factors (uncontrollable parameters), and robust design due to the minimization of the deviation of performance caused by the deviation of control factors (design variables). We achieve mathematical rigor by using, as a foundation, principles from the design of experiments and optimization. Specifically, we integrate the Response Surface Method (RSM) with the compromise Decision Support Problem (DSP). Our approach is especially useful for design problems where there are no closed-form solutions and system performance is computationally expensive to evaluate. The design of a solar powered irrigation system is used as an example. Our focus in this paper is on illustrating our approach rather than on the results per se.

Development of local calibration factors and design criteria values for mechanistic-empirical pavement design.

DOT National Transportation Integrated Search

2015-08-01

A mechanistic-empirical (ME) pavement design procedure allows for analyzing and selecting pavement structures based : on predicted distress progression resulting from stresses and strains within the pavement over its design life. The Virginia : Depar...

Development of Alabama traffic factors for use in mechanistic-empirical pavement design.

DOT National Transportation Integrated Search

2015-02-01

The pavement engineering community is moving toward design practices that use mechanistic-empirical (M-E) approaches to the design and analysis of pavement structures. This effort is : embodied in the Mechanistic-Empirical Pavement Design Guide (MEPD...

Designing the Instructional Interface.

ERIC Educational Resources Information Center

Lohr, L. L.

2000-01-01

Designing the instructional interface is a challenging endeavor requiring knowledge and skills in instructional and visual design, psychology, human-factors, ergonomic research, computer science, and editorial design. This paper describes the instructional interface, the challenges of its development, and an instructional systems approach to its…

Antinomies of Semiotics in Graphic Design

ERIC Educational Resources Information Center

Storkerson, Peter

2010-01-01

The following paper assesses the roles played by semiotics in graphic design and in graphic design education, which both reflects and shapes practice. It identifies a series of factors; graphic design education methods and culture; semiotic theories themselves and their application to graphic design; the two wings of Peircian semiotics and…

CURRENT PRACTICES OBSERVED IN DESIGN AND DRAFTING OCCUPATIONS.

ERIC Educational Resources Information Center

SQUIRES, CARL E.

DATA WHICH HAD SIGNIFICANCE FOR DESIGN AND DRAFTING CURRICULUMS WERE COLLECTED BY DIRECT OBSERVATION OF 21 DESIGN AND DRAFTING FACTORS WITHIN 16 SELECTED INDUSTRIAL COMPANIES EMPLOYING 869 DESIGNERS AND DRAFTSMEN. OBSERVATIONS COVERED (1) THE NUMBER OF DESIGN AND DRAFTING EMPLOYEES, (2) THE SYSTEM OF DRAFTING ROOM ORGANIZATION, (3) JOB…

Designers' models of the human-computer interface

NASA Technical Reports Server (NTRS)

Gillan, Douglas J.; Breedin, Sarah D.

1993-01-01

Understanding design models of the human-computer interface (HCI) may produce two types of benefits. First, interface development often requires input from two different types of experts: human factors specialists and software developers. Given the differences in their backgrounds and roles, human factors specialists and software developers may have different cognitive models of the HCI. Yet, they have to communicate about the interface as part of the design process. If they have different models, their interactions are likely to involve a certain amount of miscommunication. Second, the design process in general is likely to be guided by designers' cognitive models of the HCI, as well as by their knowledge of the user, tasks, and system. Designers do not start with a blank slate; rather they begin with a general model of the object they are designing. The author's approach to a design model of the HCI was to have three groups make judgments of categorical similarity about the components of an interface: human factors specialists with HCI design experience, software developers with HCI design experience, and a baseline group of computer users with no experience in HCI design. The components of the user interface included both display components such as windows, text, and graphics, and user interaction concepts, such as command language, editing, and help. The judgments of the three groups were analyzed using hierarchical cluster analysis and Pathfinder. These methods indicated, respectively, how the groups categorized the concepts, and network representations of the concepts for each group. The Pathfinder analysis provides greater information about local, pairwise relations among concepts, whereas the cluster analysis shows global, categorical relations to a greater extent.

Critical Factors Affecting Students' Satisfaction with Higher Education in Sri Lanka

ERIC Educational Resources Information Center

Weerasinghe, I. M. S.; Fernando, R. L. S.

2018-01-01

Purpose: The purpose of this study is to explain critical factors affecting student satisfaction levels in selected state universities in Sri Lanka. Design/methodology/approach: The study has applied an quantitative survey design guided by six hypotheses. A conceptual framework has been developed to address the research questions on the basis of a…

Development of human factors guidelines for advanced traveler information systems and commercial vehicle operations : identification of the strengths and weaknesses of alternative information display formats

DOT National Transportation Integrated Search

1998-10-01

This report is one of a series produced as part of a contract designed to develop precise, detailed, human factors design guidelines for Advanced Traveler Information Systems (ATIS) and Commercial Vehicle Operations (CVO). The goals of the work cover...

Stroke-Related Knowledge, Lifestyle Behaviours and Health Beliefs in Singaporean Chinese: Implications for Health Education

ERIC Educational Resources Information Center

Wong, Wai Pong; Yeung, Meredith; Loh, Susan; Lee, Mina; Ghazali, F.; Chan, C. J.; Feng, S.; Liew, Y. V.; Seah, P. F.; Wee, J.; Wang, J.; Huang, X.; Dean, Elizabeth

2013-01-01

Objective: The objective of the present study was to describe stroke-related knowledge (risk factors, warning signs and emergency response), lifestyle behaviours and health beliefs among Singaporean Chinese, and to identify any factors associated with such knowledge, behaviours and beliefs. Design: This was a cross-sectional study design employing…

Critical Success Factors in Crafting Strategic Architecture for E-Learning at HP University

ERIC Educational Resources Information Center

Sharma, Kunal; Pandit, Pallvi; Pandit, Parul

2011-01-01

Purpose: The purpose of this paper is to outline the critical success factors for crafting a strategic architecture for e-learning at HP University. Design/methodology/approach: A descriptive survey type of research design was used. An empirical study was conducted on students enrolled with the International Centre for Distance and Open Learning…

Human Factors in the Design of a Computer-Assisted Instruction System. Technical Progress Report.

ERIC Educational Resources Information Center

Mudge, J. C.

A research project built an author-controlled computer-assisted instruction (CAI) system to study ease-of-use factors in student-system, author-system, and programer-system interfaces. Interfaces were designed and observed in use and systematically revised. Development of course material by authors, use by students, and administrative tasks were…

Designing Their Own: Increasing Urban High School Teacher Capacity for Creating Interim Assessments

ERIC Educational Resources Information Center

Ado, Kathryn

2013-01-01

This case study analyzes and documents factors that affect teacher learning and instructional practices in connection to the design your own (DYO) interim or periodic assessment process at one newly developed high school in New York City. Examining these factors through Riggan and Nabors Olah's (2011) conceptual framework offers insights into the…

Herzberg's Theory of Motivation as Applied to Community College Full-Time and Adjunct Online Faculty

ERIC Educational Resources Information Center

Gullickson, Larry

2011-01-01

This study was designed to identify the factors that influence full-time and adjunct faculty perceptions regarding job satisfaction and dissatisfaction. It was also designed to determine if those factors relate differently to full-time and adjunct faculty. It is anticipated that this information will aid administrators in improving morale and…

24 CFR 1000.162 - How will a recipient know that non-dwelling structures assisted under the IHBG program meet the...

Code of Federal Regulations, 2010 CFR

2010-04-01

..., design, features, amenities, performance or other factors. The standards for such structures must be able to support the reasonableness and necessity for these factors and to clearly identify the affordable... change; (vi) Cultural relevance of design; (vii) Size and scope supported by population and need; (viii...

Risk Factors for Road Transport-Related Injury among Pedestrians in Rural Ghana: Implications for Road Safety Education

ERIC Educational Resources Information Center

Teye-Kwadjo, Enoch

2017-01-01

Objectives: Injuries and mortality resulting from pedestrian road traffic crashes are a major public health problem in Ghana. This study investigated risk factors for road transport-related injury among pedestrians in rural Ghana. Design: Case study design using qualitative data. Method: In-depth interviews were conducted with pedestrians.…

HEALTHY study rationale, design and methods: Moderating risk of type 2 diabetes in multi-ethnic middle school students

USDA-ARS?s Scientific Manuscript database

The HEALTHY primary prevention trial was designed and implemented in response to the growing numbers of children and adolescents being diagnosed with type 2 diabetes. The objective was to moderate risk factors for type 2 diabetes. Modifiable risk factors measured were indicators of adiposity and gly...

Designing a Mobile Training System in Rural Areas with Bayesian Factor Models

ERIC Educational Resources Information Center

Omidi Najafabadi, Maryam; Mirdamadi, Seyed Mehdi; Payandeh Najafabadi, Amir Teimour

2014-01-01

The facts that the wireless technologies (1) are more convenient; and (2) need less skill than desktop computers, play a crucial role to decrease digital gap in rural areas. This study employed the Bayesian Confirmatory Factor Analysis (CFA) to design a mobile training system in rural areas of Iran. It categorized challenges, potential, and…

The Design of Transportation Equipment in Terms of Human Capabilities. The Role of Engineering Psychology in Transport Safety.

ERIC Educational Resources Information Center

McFarland, Ross A.

Human factors engineering is considered with regard to the design of safety factors for aviation and highway transportation equipment. Current trends and problem areas are identified for jet air transportation and for highway transportation. Suggested solutions to transportation safety problems are developed by applying the techniques of human…

An Exploratory Study of Interactivity in Visualization Tools: "Flow" of Interaction

ERIC Educational Resources Information Center

Liang, Hai-Ning; Parsons, Paul C.; Wu, Hsien-Chi; Sedig, Kamran

2010-01-01

This paper deals with the design of interactivity in visualization tools. There are several factors that can be used to guide the analysis and design of the interactivity of these tools. One such factor is flow, which is concerned with the duration of interaction with visual representations of information--interaction being the actions performed…

Analysis of Factors Influencing Creative Personality of Elementary School Students

ERIC Educational Resources Information Center

Park, Jongman; Kim, Minkee; Jang, Shinho

2017-01-01

This quantitative research examined factors that affect elementary students' creativity and how those factors correlate. Aiming to identify significant factors that affect creativity and to clarify the relationship between these factors by path analysis, this research was designed to be a stepping stone for creativity enhancement studies. Data…

14 CFR 25.619 - Special factors.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Special factors. 25.619 Section 25.619... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction General § 25.619 Special factors. The factor of safety prescribed in § 25.303 must be multiplied by the highest pertinent special factor of safety...

A Review of CEFA Software: Comprehensive Exploratory Factor Analysis Program

ERIC Educational Resources Information Center

Lee, Soon-Mook

2010-01-01

CEFA 3.02(Browne, Cudeck, Tateneni, & Mels, 2008) is a factor analysis computer program designed to perform exploratory factor analysis. It provides the main properties that are needed for exploratory factor analysis, namely a variety of factoring methods employing eight different discrepancy functions to be minimized to yield initial…

Study of simple CFRP-metal joint failure

NASA Astrophysics Data System (ADS)

Cheng, Jingquan; Rodriguez, Antonio; Emerson, Nicolas; Symmes, Arthur

2008-07-01

In millimeter wavelength telescope design and construction, there have been a number of mysterious failures of simple CFRF-metal joints. Telescope designers have not had satisfactory interpretations of these failures. In this paper, factors which may influence the failure of joints are discussed. These include stress concentration, material creep, joint fatigue, reasons related to chemical process and manufacture process. Extrapolation formulas for material creep, joint fatigue, and differential thermal stresses are derived in this paper. Detailed chemical and manufacturing factors are also discussed. All these issues are the causes of a number of early failures under a loading which is significantly lower than the strength of adhesives used. For ensuring reliability of a precision instrument structure joint, the designer should have a thorough understanding of all these factors.

Optimal experimental design in an epidermal growth factor receptor signalling and down-regulation model.

PubMed

Casey, F P; Baird, D; Feng, Q; Gutenkunst, R N; Waterfall, J J; Myers, C R; Brown, K S; Cerione, R A; Sethna, J P

2007-05-01

We apply the methods of optimal experimental design to a differential equation model for epidermal growth factor receptor signalling, trafficking and down-regulation. The model incorporates the role of a recently discovered protein complex made up of the E3 ubiquitin ligase, Cbl, the guanine exchange factor (GEF), Cool-1 (beta -Pix) and the Rho family G protein Cdc42. The complex has been suggested to be important in disrupting receptor down-regulation. We demonstrate that the model interactions can accurately reproduce the experimental observations, that they can be used to make predictions with accompanying uncertainties, and that we can apply ideas of optimal experimental design to suggest new experiments that reduce the uncertainty on unmeasurable components of the system.

Human factors in telemanipulation: Perspectives from the Oak Ridge National Laboratory experience

DOE Office of Scientific and Technical Information (OSTI.GOV)

Draper, J.V.

1994-01-01

Personnel at the Robotics and Process Systems Division (RPSD) of the Oak Ridge National Laboratory (ORNL) have extensive experience designing, building, and operating teleoperators for a variety of settings, including space, battlefields, nuclear fuel reprocessing plants, and hazardous waste retrieval. In the course of the last decade and a half, the RPSD designed, built, and operated 4 telemanipulators (M-2, ASM, LTM, CESAR arm) and operated another half dozen (M-8, Model 50, TOS SM-229, RM-10, PaR 5000, BilArm 83A). During this period, human factors professionals have been closely integrated with RPSD design teams, investigating telemanipulator feedback and feed forward, designing cockpitsmore » and control rooms, training users and designers, and helping to develop performance specifications for telemanipulators. This paper presents a brief review of this and other work, with an aim towards providing perspectives on some of the human factors aspects of telemanipulation. The first section of the paper examines user tasks during supervisory control and discusses how telemanipulator responsiveness determines the appropriate control metaphor for continuous manual control. The second section provides an ecological perspective on telemanipulator feedback and feed-forward. The third section briefly describes the RPSD control room design approach and how design projects often serve as systems integrators.« less

A framework for reporting on human factor/usability studies of health information technologies.

PubMed

Peute, Linda W; Driest, Keiko F; Marcilly, Romaric; Bras Da Costa, Sabrina; Beuscart-Zephir, Marie-Catherine; Jaspers, Monique W M

2013-01-01

Increasingly, studies are being published on the potential negative effect of introducing poor designed Health Information Technology (HIT) into clinical settings, relating to technology-induced errors and adverse events. Academic research on HIT design and evaluation is an extremely important source of information in providing new insights into factors contributing to successful system (re)design efforts, system user-friendliness and usability issues and safety critical aspects of HIT design. However, these studies have been inconsistent and incomprehensive in their reporting, complicating the appraisal of outcomes, generalizability of study findings, meta-analysis and harmonization of the available evidence. To improve identification of type of use errors and safety related issues regarding design and implementation of HIT, consensus on issues to be reported on in scientific publications is a necessary step forward. This study presents the first approach to a framework providing a set of principles to follow for comprehensive and unambiguous reporting of HIT design and usability evaluation studies with the objective to reduce variation, improve on the publication reporting quality and proper indexation of these studies. This framework may be helpful in expanding the knowledge base not only concerning the application of Human Factors (HF)/Usability studies of HIT but also improve the knowledge base of how to (re)design and implement effective, efficient and safe HIT.

Measuring and Advancing Experimental Design Ability in an Introductory Course without Altering Existing Lab Curriculum.

PubMed

Shanks, Ryan A; Robertson, Chuck L; Haygood, Christian S; Herdliksa, Anna M; Herdliska, Heather R; Lloyd, Steven A

2017-01-01

Introductory biology courses provide an important opportunity to prepare students for future courses, yet existing cookbook labs, although important in their own way, fail to provide many of the advantages of semester-long research experiences. Engaging, authentic research experiences aid biology students in meeting many learning goals. Therefore, overlaying a research experience onto the existing lab structure allows faculty to overcome barriers involving curricular change. Here we propose a working model for this overlay design in an introductory biology course and detail a means to conduct this lab with minimal increases in student and faculty workloads. Furthermore, we conducted exploratory factor analysis of the Experimental Design Ability Test (EDAT) and uncovered two latent factors which provide valid means to assess this overlay model's ability to increase advanced experimental design abilities. In a pre-test/post-test design, we demonstrate significant increases in both basic and advanced experimental design abilities in an experimental and comparison group. We measured significantly higher gains in advanced experimental design understanding in students in the experimental group. We believe this overlay model and EDAT factor analysis contribute a novel means to conduct and assess the effectiveness of authentic research experiences in an introductory course without major changes to the course curriculum and with minimal increases in faculty and student workloads.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Skochko, G.W.; Herrmann, T.P.

Axial load cycling fatigue tests of threaded fasteners are useful in determining fastener fatigue failure or design properties. By using appropriate design factors between the failure and design fatigue strengths, such tests are used to establish fatigue failure and design parameters of fasteners for axial and bending cyclic load conditions. This paper reviews the factors which influence the fatigue strength of low Alloy steel threaded fasteners, identifies those most significant to fatigue strength, and provides design guidelines based on the direct evaluation of fatigue tests of threaded fasteners. Influences on fatigue strength of thread manufacturing process (machining and rolling ofmore » threads), effect of fastener membrane and bending stresses, thread root radii, fastener sizes, fastener tensile strength, stress relaxation, mean stress, and test temperature are discussed.« less

Design engineer perceptions and attitudes regarding human factors application to nuclear power plant design

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, R.; Jones, J. M.

2006-07-01

With the renewed interest in nuclear power and the possibility of constructing new reactors within the next decade in the U.S., there are several challenges for the regulators, designers, and vendors. One challenge is to ensure that Human Factors Engineering (HFE) is involved, and correctly applied in the life-cycle design of the Nuclear Power Plant (NPP). As an important part of the effort, people would ask: 'is the system-design engineer effectively incorporating HFE in the NPPs design?' The present study examines the sagacity of Instrumentation and Control design engineers on issues relating to awareness, attitude, and application of HFE inmore » NPP design. A questionnaire was developed and distributed, focusing on the perceptions and attitudes of the design engineers. The responses revealed that, while the participants had a relatively high positive attitude about HFE, their awareness and application of HFE were moderate. The results also showed that senior engineers applied HFE more frequently in their design work than young engineers. This study provides some preliminary results and implications for improved HFE education and application in NPP design. (authors)« less

Designing to Control Flight Crew Errors

NASA Technical Reports Server (NTRS)

Schutte, Paul C.; Willshire, Kelli F.

1997-01-01

It is widely accepted that human error is a major contributing factor in aircraft accidents. There has been a significant amount of research in why these errors occurred, and many reports state that the design of flight deck can actually dispose humans to err. This research has led to the call for changes in design according to human factors and human-centered principles. The National Aeronautics and Space Administration's (NASA) Langley Research Center has initiated an effort to design a human-centered flight deck from a clean slate (i.e., without constraints of existing designs.) The effort will be based on recent research in human-centered design philosophy and mission management categories. This design will match the human's model of the mission and function of the aircraft to reduce unnatural or non-intuitive interfaces. The product of this effort will be a flight deck design description, including training and procedures, and a cross reference or paper trail back to design hypotheses, and an evaluation of the design. The present paper will discuss the philosophy, process, and status of this design effort.

Extravehicular Activity training and hardware design considerations

NASA Technical Reports Server (NTRS)

Thuot, Pierre J.; Harbaugh, Gregory J.

1993-01-01

Designing hardware that can be successfully operated by EVA astronauts for EVA tasks required to assemble and maintain Space Station Freedom requires a thorough understanding of human factors and of the capabilities and limitations of the space-suited astronaut, as well as of the effect of microgravity environment on the crew member's capabilities and on the overhead associated with EVA. This paper describes various training methods and facilities that are being designed for training EVA astronauts for Space Station assembly and maintenance, taking into account the above discussed factors. Particular attention is given to the user-friendly hardware design for EVA and to recent EVA flight experience.

Temperature control of the Mariner class spacecraft - A seven mission summary.

NASA Technical Reports Server (NTRS)

Dumas, L. N.

1973-01-01

Mariner spacecraft have completed five missions of scientific investigation of the planets. Two additional missions are planned. A description of the thermal design of these seven spacecraft is given herein. The factors which have influenced the thermal design include the mission requirements and constraints, the flight environment, certain programmatic considerations and the experience gained as each mission is completed. These factors are reviewed and the impact of each on thermal design and developmental techniques is assessed. It is concluded that the flight success of these spacecraft indicates that adequate temperature control has been obtained, but that improvements in design data, hardware performance and analytical techniques are needed.

Total Dose Effects in Conventional Bipolar Transistors

NASA Technical Reports Server (NTRS)

Johnston, A. H.; Swift, G. W.; Rax, B. G.

1994-01-01

This paper examines various factors in bipolar device construction and design, and discusses their impact on radiation hardness. The intent of the paper is to improve understanding of the underlying mechanisms for practical devices without special test structures, and to provide (1) guidance in ways to select transistor designs that are more resistant to radiation damage, and (2) methods to estimate the maximum amount of damage that might be expected from a basic transistor design. The latter factor is extremely important in assessing the risk that future lots of devices will be substantially below design limits, which are usually based on test data for older devices.

Wide band design on the scaled absorbing material filled with flaky CIPs

NASA Astrophysics Data System (ADS)

Xu, Yonggang; Yuan, Liming; Gao, Wei; Wang, Xiaobing; Liang, Zichang; Liao, Yi

2018-02-01

The scaled target measurement is an important method to get the target characteristic. Radar absorbing materials are widely used in the low detectable target, considering the absorbing material frequency dispersion characteristics, it makes designing and manufacturing scaled radar absorbing materials on the scaled target very difficult. This paper proposed a wide band design method on the scaled absorbing material of the thin absorption coating with added carbonyl iron particles. According to the theoretical radar cross section (RCS) of the plate, the reflection loss determined by the permittivity and permeability was chosen as the main design factor. Then, the parameters of the scaled absorbing materials were designed using the effective medium theory, and the scaled absorbing material was constructed. Finally, the full-size coating plate and scaled coating plates (under three different scale factors) were simulated; the RCSs of the coating plates were numerically calculated and measured at 4 GHz and a scale factor of 2. The results showed that the compensated RCS of the scaled coating plate was close to that of the full-size coating plate, that is, the mean deviation was less than 0.5 dB, and the design method for the scaled material was very effective.

Human factors engineering verification and validation for APR1400 computerized control room

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shin, Y. C.; Moon, H. K.; Kim, J. H.

2006-07-01

This paper introduces the Advanced Power Reactor 1400 (APR1400) HFE V and V activities the Korea Hydro Nuclear Plant Co. LTD. (KHNP) has performed for the last 10 years and some of the lessons learned through these activities. The features of APR1400 main control room include large display panel, redundant compact workstations, computer-based procedure, and safety console. Several iterations of human factors evaluations have been performed from small scale proof of concept tests to large scale integrated system tests for identifying human engineering deficiencies in the human system interface design. Evaluations in the proof of concept test were focused onmore » checking the presence of any show stopper problems in the design concept. Later evaluations were mostly for finding design problems and for assuring the resolution of human factors issues of advanced control room. The results of design evaluations were useful not only for refining the control room design, but also for licensing the standard design. Several versions of APR1400 mock-ups with dynamic simulation models of currently operating Korea Standard Nuclear Plant (KSNP) have been used for the evaluations with the participation of operators from KSNP plants. (authors)« less

Energy efficiency façade design in high-rise apartment buildings using the calculation of solar heat transfer through windows with shading devices

NASA Astrophysics Data System (ADS)

Ha, P. T. H.

2018-04-01

The architectural design orientation at the first design stage plays a key role and has a great impact on the energy consumption of a building throughout its life-cycle. To provide designers with a simple and useful tool in quantitatively determining and simply optimizing the energy efficiency of a building at the very first stage of conceptual design, a factor namely building envelope energy efficiency (Khqnl ) should be investigated and proposed. Heat transfer through windows and other glazed areas of mezzanine floors accounts for 86% of overall thermal transfer through building envelope, so the factor Khqnl of high-rise buildings largely depends on shading solutions. The author has established tables and charts to make reference to the values of Khqnl factor in certain high-rise apartment buildings in Hanoi calculated with a software program subject to various inputs including: types and sizes of shading devices, building orientations and at different points of time to be respectively analyzed. It is possible and easier for architects to refer to these tables and charts in façade design for a higher level of energy efficiency.

Development of an Integrated Human Factors Toolkit

NASA Technical Reports Server (NTRS)

Resnick, Marc L.

2003-01-01

An effective integration of human abilities and limitations is crucial to the success of all NASA missions. The Integrated Human Factors Toolkit facilitates this integration by assisting system designers and analysts to select the human factors tools that are most appropriate for the needs of each project. The HF Toolkit contains information about a broad variety of human factors tools addressing human requirements in the physical, information processing and human reliability domains. Analysis of each tool includes consideration of the most appropriate design stage, the amount of expertise in human factors that is required, the amount of experience with the tool and the target job tasks that are needed, and other factors that are critical for successful use of the tool. The benefits of the Toolkit include improved safety, reliability and effectiveness of NASA systems throughout the agency. This report outlines the initial stages of development for the Integrated Human Factors Toolkit.

Design Guidelines and Criteria for User/Operator Transactions with Battlefield Automated Systems. Volume III-A. Human Factors Analyses of User/ Operator Transactions with TACFIRE - The Tactical Fire Direction System

DTIC Science & Technology

1981-02-01

7. Reseaarch Product 81-26 - DESIGN GUIDELINES AND CRITERIA FOR USER/ I;. I’OPERATOR TRANSACTIONS WITH BATTLEFIELD AUTOMIATED SYSTEMS I’ /HVtAN...FACTORS XWLYSES :’F K~R/ OPERATOR TRANSACTIONS WTHT TACFIRE - THE TACTICAL FIRE DiRECTION SY2T3EM A HUMAN FACTORS TECHNICAL AREA L~h~h K L-J 1’ U~~i~ ll...Battlefield Auto- Inter : Oct 1979-Feb 1981 mated Systems Volume III-A: Human Factors 4t C/ Analyses of User/Operator Transactions with 6. PERFORMING

Automatic Speech Recognition in Air Traffic Control: a Human Factors Perspective

NASA Technical Reports Server (NTRS)

Karlsson, Joakim

1990-01-01

The introduction of Automatic Speech Recognition (ASR) technology into the Air Traffic Control (ATC) system has the potential to improve overall safety and efficiency. However, because ASR technology is inherently a part of the man-machine interface between the user and the system, the human factors issues involved must be addressed. Here, some of the human factors problems are identified and related methods of investigation are presented. Research at M.I.T.'s Flight Transportation Laboratory is being conducted from a human factors perspective, focusing on intelligent parser design, presentation of feedback, error correction strategy design, and optimal choice of input modalities.

Real-time PCR probe optimization using design of experiments approach.

PubMed

Wadle, S; Lehnert, M; Rubenwolf, S; Zengerle, R; von Stetten, F

2016-03-01

Primer and probe sequence designs are among the most critical input factors in real-time polymerase chain reaction (PCR) assay optimization. In this study, we present the use of statistical design of experiments (DOE) approach as a general guideline for probe optimization and more specifically focus on design optimization of label-free hydrolysis probes that are designated as mediator probes (MPs), which are used in reverse transcription MP PCR (RT-MP PCR). The effect of three input factors on assay performance was investigated: distance between primer and mediator probe cleavage site; dimer stability of MP and target sequence (influenza B virus); and dimer stability of the mediator and universal reporter (UR). The results indicated that the latter dimer stability had the greatest influence on assay performance, with RT-MP PCR efficiency increased by up to 10% with changes to this input factor. With an optimal design configuration, a detection limit of 3-14 target copies/10 μl reaction could be achieved. This improved detection limit was confirmed for another UR design and for a second target sequence, human metapneumovirus, with 7-11 copies/10 μl reaction detected in an optimum case. The DOE approach for improving oligonucleotide designs for real-time PCR not only produces excellent results but may also reduce the number of experiments that need to be performed, thus reducing costs and experimental times.

The science of human factors: separating fact from fiction

PubMed Central

Russ, Alissa L; Fairbanks, Rollin J; Karsh, Ben-Tzion; Militello, Laura G; Saleem, Jason J; Wears, Robert L

2013-01-01

Background Interest in human factors has increased across healthcare communities and institutions as the value of human centred design in healthcare becomes increasingly clear. However, as human factors is becoming more prominent, there is growing evidence of confusion about human factors science, both anecdotally and in scientific literature. Some of the misconceptions about human factors may inadvertently create missed opportunities for healthcare improvement. Methods The objective of this article is to describe the scientific discipline of human factors and provide common ground for partnerships between healthcare and human factors communities. Results The primary goal of human factors science is to promote efficiency, safety and effectiveness by improving the design of technologies, processes and work systems. As described in this article, human factors also provides insight on when training is likely (or unlikely) to be effective for improving patient safety. Finally, we outline human factors specialty areas that may be particularly relevant for improving healthcare delivery and provide examples to demonstrate their value. Conclusions The human factors concepts presented in this article may foster interdisciplinary collaborations to yield new, sustainable solutions for healthcare quality and patient safety. PMID:23592760

Design and prediction of new anticoagulants as a selective Factor IXa inhibitor via three-dimensional quantitative structure-property relationships of amidinobenzothiophene derivatives.

PubMed

Gao, Jia-Suo; Tong, Xu-Peng; Chang, Yi-Qun; He, Yu-Xuan; Mei, Yu-Dan; Tan, Pei-Hong; Guo, Jia-Liang; Liao, Guo-Chao; Xiao, Gao-Keng; Chen, Wei-Min; Zhou, Shu-Feng; Sun, Ping-Hua

2015-01-01

Factor IXa (FIXa), a blood coagulation factor, is specifically inhibited at the initiation stage of the coagulation cascade, promising an excellent approach for developing selective and safe anticoagulants. Eighty-four amidinobenzothiophene antithrombotic derivatives targeting FIXa were selected to establish three-dimensional quantitative structure-activity relationship (3D-QSAR) and three-dimensional quantitative structure-selectivity relationship (3D-QSSR) models using comparative molecular field analysis and comparative similarity indices analysis methods. Internal and external cross-validation techniques were investigated as well as region focusing and bootstrapping. The satisfactory q (2) values of 0.753 and 0.770, and r (2) values of 0.940 and 0.965 for 3D-QSAR and 3D-QSSR, respectively, indicated that the models are available to predict both the inhibitory activity and selectivity on FIXa against Factor Xa, the activated status of Factor X. This work revealed that the steric, hydrophobic, and H-bond factors should appropriately be taken into account in future rational design, especially the modifications at the 2'-position of the benzene and the 6-position of the benzothiophene in the R group, providing helpful clues to design more active and selective FIXa inhibitors for the treatment of thrombosis. On the basis of the three-dimensional quantitative structure-property relationships, 16 new potent molecules have been designed and are predicted to be more active and selective than Compound 33, which has the best activity as reported in the literature.

Design and prediction of new anticoagulants as a selective Factor IXa inhibitor via three-dimensional quantitative structure-property relationships of amidinobenzothiophene derivatives

PubMed Central

Gao, Jia-Suo; Tong, Xu-Peng; Chang, Yi-Qun; He, Yu-Xuan; Mei, Yu-Dan; Tan, Pei-Hong; Guo, Jia-Liang; Liao, Guo-Chao; Xiao, Gao-Keng; Chen, Wei-Min; Zhou, Shu-Feng; Sun, Ping-Hua

2015-01-01

Factor IXa (FIXa), a blood coagulation factor, is specifically inhibited at the initiation stage of the coagulation cascade, promising an excellent approach for developing selective and safe anticoagulants. Eighty-four amidinobenzothiophene antithrombotic derivatives targeting FIXa were selected to establish three-dimensional quantitative structure–activity relationship (3D-QSAR) and three-dimensional quantitative structure–selectivity relationship (3D-QSSR) models using comparative molecular field analysis and comparative similarity indices analysis methods. Internal and external cross-validation techniques were investigated as well as region focusing and bootstrapping. The satisfactory q2 values of 0.753 and 0.770, and r2 values of 0.940 and 0.965 for 3D-QSAR and 3D-QSSR, respectively, indicated that the models are available to predict both the inhibitory activity and selectivity on FIXa against Factor Xa, the activated status of Factor X. This work revealed that the steric, hydrophobic, and H-bond factors should appropriately be taken into account in future rational design, especially the modifications at the 2′-position of the benzene and the 6-position of the benzothiophene in the R group, providing helpful clues to design more active and selective FIXa inhibitors for the treatment of thrombosis. On the basis of the three-dimensional quantitative structure–property relationships, 16 new potent molecules have been designed and are predicted to be more active and selective than Compound 33, which has the best activity as reported in the literature. PMID:25848211

How Universal Are Universal Symbols? An Estimation of Cross-Cultural Adoption of Universal Healthcare Symbols.

PubMed

Joy Lo, Chih-Wei; Yien, Huey-Wen; Chen, I-Ping

2016-04-01

To evaluate the effectiveness of universal health symbol usage and to analyze the factors influencing the adoption of those symbols in Taiwan. Universal symbols are an important innovative tool for health facility wayfinding systems. Hablamos Juntos, a universal healthcare symbol system developed in the United States, is a thoughtful, well-designed, and thoroughly tested symbol system that facilitates communication across languages and cultures. We designed a questionnaire to test how well the selected graphic symbols were understood by Taiwanese participants and determined factors related to successful symbol decoding, including participant-related factors, stimulation factors, and the interaction between stimulation and participants. Additionally, we further established a design principle for future development of localized healthcare symbols. (1) Eleven symbols were identified as highly comprehensible and effective symbols that can be directly adopted in Taiwanese healthcare settings. Sixteen symbols were deemed incomprehensible or confusing and thus had to be redesigned. Finally, 14 were identified as relatively incomprehensible and could thus be redesigned and then have their effectiveness evaluated again. (2) Three factors were found to influence the participants' differing levels of comprehension of the Hablamos Juntos symbols. In order to prevent the three aforementioned factors from causing difficulty in interpreting symbols, we suggest that the local symbol designers should (1) use more iconic images, (2) carefully evaluate the indexical and symbolic meaning of graphic symbols, and (3) collect the consensus of Taiwanese people with different educational backgrounds. © The Author(s) 2016.

The Role of Healthy Social Interaction and Communications in Provoking Creativity in the Design Studio

ERIC Educational Resources Information Center

Sidawi, Bhzad

2016-01-01

Design is a social phenomenon and researchers suggest that negotiations and communications between designers are essential to initiate creativity. Within the design studio environment, a number of factors affect the healthy social interaction and design negotiations, such as the teaching style of tutors and the culture that governs a design studio…

CONCEPTUAL DESIGNS FOR A NEW HIGHWAY VEHICLE EMISSIONS ESTIMATION METHODOLOGY

EPA Science Inventory

The report discusses six conceptual designs for a new highway vehicle emissions estimation methodology and summarizes the recommendations of each design for improving the emissions and activity factors in the emissions estimation process. he complete design reports are included a...

Factor Structure of the Penn State Worry Questionnaire: Examination of a Method Factor

ERIC Educational Resources Information Center

Hazlett-Stevens, Holly; Ullman, Jodie B.; Craske, Michelle G.

2004-01-01

The Penn State Worry Questionnaire (PSWQ) was originally designed as a unifactorial measure of pathological trait worry. However, recent studies supported a two-factor solution with positively worded items loading on the first factor and reverse-scored items loading on a second factor. The current study compared this two-factor model to a negative…

14 CFR 27.337 - Limit maneuvering load factor.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factor. 27.337... Limit maneuvering load factor. The rotorcraft must be designed for— (a) A limit maneuvering load factor... load factor not less than 2.0 and any negative limit maneuvering load factor of not less than −0.5 for...

14 CFR 29.337 - Limit maneuvering load factor.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factor. 29.337... Limit maneuvering load factor. The rotorcraft must be designed for— (a) A limit maneuvering load factor... load factor not less than 2.0 and any negative limit maneuvering load factor of not less than −0.5 for...

Schools to Scale.

ERIC Educational Resources Information Center

Gisolfi, Peter A.

1999-01-01

A firm that has designed many preschool and elementary school projects identifies three factors that are vital to successful design for young children: protection, interaction, and scale. Accompanying drawings of three projects illustrate these design principles. (MLF)

Affordable passive solar homes - low-cost, compact designs. [Glossary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crowther, R.L.

1984-01-01

The designs and plans of this book present total, integrative, energy design. They carefully integrate site, architecture, and interior for various population segments that meet a frugal budget. The book is divided into two sections. The first part gives data concerning design, construction, site, climatic factors, materials, interiors, financing, and other home ownership factors that enhance affordability. Basic information on the design assumptions and considerations incorporate into the homes is presented, along with passive solar systems descriptions. The second part presents designs and plans with a brief review of considerations that serve defined human living needs, as well single-family, attached,more » or multiple residential configurations. The plans are based on a dimensional grid using 4-foot and 2-foot (1.2 meter and .61 meter) increments compatible with economic standard lumber and materials sizes.« less

Anatomical Thin Titanium Mesh Plate Structural Optimization for Zygomatic-Maxillary Complex Fracture under Fatigue Testing.

PubMed

Wang, Yu-Tzu; Huang, Shao-Fu; Fang, Yu-Ting; Huang, Shou-Chieh; Cheng, Hwei-Fang; Chen, Chih-Hao; Wang, Po-Fang; Lin, Chun-Li

2018-01-01

This study performs a structural optimization of anatomical thin titanium mesh (ATTM) plate and optimal designed ATTM plate fabricated using additive manufacturing (AM) to verify its stabilization under fatigue testing. Finite element (FE) analysis was used to simulate the structural bending resistance of a regular ATTM plate. The Taguchi method was employed to identify the significance of each design factor in controlling the deflection and determine an optimal combination of designed factors. The optimal designed ATTM plate with patient-matched facial contour was fabricated using AM and applied to a ZMC comminuted fracture to evaluate the resting maxillary micromotion/strain under fatigue testing. The Taguchi analysis found that the ATTM plate required a designed internal hole distance to be 0.9 mm, internal hole diameter to be 1 mm, plate thickness to be 0.8 mm, and plate height to be 10 mm. The designed plate thickness factor primarily dominated the bending resistance up to 78% importance. The averaged micromotion (displacement) and strain of the maxillary bone showed that ZMC fracture fixation using the miniplate was significantly higher than those using the AM optimal designed ATTM plate. This study concluded that the optimal designed ATTM plate with enough strength to resist the bending effect can be obtained by combining FE and Taguchi analyses. The optimal designed ATTM plate with patient-matched facial contour fabricated using AM provides superior stabilization for ZMC comminuted fractured bone segments.

How shall we design the future vehicle for Chinese market.

PubMed

Chen, Fang; Wang, Minjuan; Zhu, Xi Chan; Li, Jiaqi

2012-01-01

Surface transportation system is developing very fast in China and the number of vehicles is increasing quickly as well. This development creates a lot of problems on traffic safety and the number of accident is also increasing. In this paper, we made deep analysis of different possible causes of safety problems through three aspects: the traffic environment and infrastructure, in-vehicle information system design and the characteristics of drivers. There are many factors in each aspects may contribute to the transportation safety problems. Problems with infrastructure design and traffic design contribute over 50% of the traffic accident. Another important factor is that people has very little traffic safety concept and very weak on understanding the important of right behavior on the road. This paper has pointed the urgent needs to study the human factors in road and transportation system and vehicle HMI design, as there are very few such studies available in literature based on Chinese situation. The paper also proposed the needs to develop proactive educational system that can promote driver's understanding of traffic safety and to take the right action during drive.

Previous experience in manned space flight: A survey of human factors lessons learned

NASA Technical Reports Server (NTRS)

Chandlee, George O.; Woolford, Barbara

1993-01-01

Previous experience in manned space flight programs can be used to compile a data base of human factors lessons learned for the purpose of developing aids in the future design of inhabited spacecraft. The objectives are to gather information available from relevant sources, to develop a taxonomy of human factors data, and to produce a data base that can be used in the future for those people involved in the design of manned spacecraft operations. A study is currently underway at the Johnson Space Center with the objective of compiling, classifying, and summarizing relevant human factors data bearing on the lessons learned from previous manned space flights. The research reported defines sources of data, methods for collection, and proposes a classification for human factors data that may be a model for other human factors disciplines.

Leveraging Health Care Simulation Technology for Human Factors Research: Closing the Gap Between Lab and Bedside.

PubMed

Deutsch, Ellen S; Dong, Yue; Halamek, Louis P; Rosen, Michael A; Taekman, Jeffrey M; Rice, John

2016-11-01

We describe health care simulation, designed primarily for training, and provide examples of how human factors experts can collaborate with health care professionals and simulationists-experts in the design and implementation of simulation-to use contemporary simulation to improve health care delivery. The need-and the opportunity-to apply human factors expertise in efforts to achieve improved health outcomes has never been greater. Health care is a complex adaptive system, and simulation is an effective and flexible tool that can be used by human factors experts to better understand and improve individual, team, and system performance within health care. Expert opinion is presented, based on a panel delivered during the 2014 Human Factors and Ergonomics Society Health Care Symposium. Diverse simulators, physically or virtually representing humans or human organs, and simulation applications in education, research, and systems analysis that may be of use to human factors experts are presented. Examples of simulation designed to improve individual, team, and system performance are provided, as are applications in computational modeling, research, and lifelong learning. The adoption or adaptation of current and future training and assessment simulation technologies and facilities provides opportunities for human factors research and engineering, with benefits for health care safety, quality, resilience, and efficiency. Human factors experts, health care providers, and simulationists can use contemporary simulation equipment and techniques to study and improve health care delivery. © 2016, Human Factors and Ergonomics Society.

Calculation Method of Lateral Strengths and Ductility Factors of Constructions with Shear Walls of Different Ductility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamaguchi, Nobuyoshi; Nakao, Masato; Murakami, Masahide

2008-07-08

For seismic design, ductility-related force modification factors are named R factor in Uniform Building Code of U.S, q factor in Euro Code 8 and Ds (inverse of R) factor in Japanese Building Code. These ductility-related force modification factors for each type of shear elements are appeared in those codes. Some constructions use various types of shear walls that have different ductility, especially for their retrofit or re-strengthening. In these cases, engineers puzzle the decision of force modification factors of the constructions. Solving this problem, new method to calculate lateral strengths of stories for simple shear wall systems is proposed andmore » named 'Stiffness--Potential Energy Addition Method' in this paper. This method uses two design lateral strengths for each type of shear walls in damage limit state and safety limit state. Two lateral strengths of stories in both limit states are calculated from these two design lateral strengths for each type of shear walls in both limit states. Calculated strengths have the same quality as values obtained by strength addition method using many steps of load-deformation data of shear walls. The new method to calculate ductility factors is also proposed in this paper. This method is based on the new method to calculate lateral strengths of stories. This method can solve the problem to obtain ductility factors of stories with shear walls of different ductility.« less

The study on length and diameter ratio of nail as preliminary design for slope stabilization

NASA Astrophysics Data System (ADS)

Gunawan, Indra; Silmi Surjandari, Niken; Muslih Purwana, Yusep

2017-11-01

Soil nailing technology has been widely applied in practice for reinforced slope. The number of studies for the effective design of nail-reinforced slopes has also increased. However, most of the previous study was focused on a safety factor of the slope; the ratio of length and diameter itself has likely never been studied before. The aim of this study is to relate the length and diameter ratio of the nail with the safety factor of the 20 m height of sand slope in the various angle of friction and steepness of the slope. Simplified Bishop method was utilized to analyze the safety factor of the slope. This study is using data simulation to calculate the safety factor of the slope with soil nailing reinforcement. The results indicate that safety factor of slope stability increases with the increase of length and diameter ratio of the nail. At any angle of friction and steepness of the slope, certain effective length and diameter ratio was obtain. These results may be considered as a preliminary design for slope stabilization.

Power inversion design for ocean wave energy harvesting

NASA Astrophysics Data System (ADS)

Talebani, Anwar N.

The needs for energy sources are increasing day by day because of several factors, such as oil depletion, and global climate change due to the higher level of CO2, so the exploration of various renewable energy sources is very promising area of study. The available ocean waves can be utilized as free source of energy as the water covers 70% of the earth surface. This thesis presents the ocean wave energy as a source of renewable energy. By addressing the problem of designing efficient power electronics system to deliver 5 KW from the induction generator to the grid with less possible losses and harmonics as possible and to control current fed to the grid to successfully harvest ocean wave energy. We design an AC-DC full bridge rectifier converter, and a DC-DC boost converter to harvest wave energy from AC to regulated DC. In order to increase the design efficiency, we need to increase the power factor from (0.5-0.6) to 1. This is accomplished by designing the boost converter with power factor correction in continues mode with RC circuit as an input to the boost converter power factor correction. This design results in a phase shift between the input current and voltage of the full bridge rectifier to generate a small reactive power. The reactive power is injected to the induction generator to maintain its functionality by generating a magnetic field in its stator. Next, we design a single-phase pulse width modulator full bridge voltage source DC-AC grid-tied mode inverter to harvest regulated DC wave energy to AC. The designed inverter is modulated by inner current loop, to control current injected to the grid with minimal filter component to maintain power quality at the grid. The simulation results show that our design successfully control the current level fed to the grid. It is noteworthy that the simulated efficiency is higher than the calculated one since we used an ideal switch in the simulated circuit.

Mobile Applications for Patient-centered Care Coordination: A Review of Human Factors Methods Applied to their Design, Development, and Evaluation

PubMed Central

Westbrook, J. I.

2015-01-01

Summary Objectives To examine if human factors methods were applied in the design, development, and evaluation of mobile applications developed to facilitate aspects of patient-centered care coordination. Methods We searched MEDLINE and EMBASE (2013-2014) for studies describing the design or the evaluation of a mobile health application that aimed to support patients’ active involvement in the coordination of their care. Results 34 papers met the inclusion criteria. Applications ranged from tools that supported self-management of specific conditions (e.g. asthma) to tools that provided coaching or education. Twelve of the 15 papers describing the design or development of an app reported the use of a human factors approach. The most frequently used methods were interviews and surveys, which often included an exploration of participants’ current use of information technology. Sixteen papers described the evaluation of a patient application in practice. All of them adopted a human factors approach, typically an examination of the use of app features and/or surveys or interviews which enquired about patients’ views of the effects of using the app on their behaviors (e.g. medication adherence), knowledge, and relationships with healthcare providers. No study in our review assessed the impact of mobile applications on health outcomes. Conclusion The potential of mobile health applications to assist patients to more actively engage in the management of their care has resulted in a large number of applications being developed. Our review showed that human factors approaches are nearly always adopted to some extent in the design, development, and evaluation of mobile applications. PMID:26293851

The role of incentive design, incentive value, communications strategy, and worksite culture on health risk assessment participation.

PubMed

Seaverson, Erin L D; Grossmeier, Jessica; Miller, Toni M; Anderson, David R

2009-01-01

To examine the impact of financial incentives, communications strategy, and worksite culture on health risk assessment (HRA) participation rates. A cross-sectional study design was used to examine factors that influence employee participation, including incentive value, incentive design, communications strategy, and worksite culture. Large private-sector and public-sector employers. Thirty-six employers (n = 559,988 employees) that provided financial incentives to promote employee HRA participation. Organizations implemented the HRA as part of a more comprehensive worksite health promotion strategy that included follow-up interventions and a variety of other components. The primary outcome of interest was employee HRA participation. Information on program design and structure, as well as on HRA eligibility and participation, was collected for each organization via standard client report and semistructured interviews with account managers. General linear regression models were used to examine the extent to which factors influence HRA participation independently and when controlled for other factors. Incentive value (r2 = .433; p < .000), benefits-integrated incentive design (r2 = .184; p = .009), culture (r2 = .113; p = .045), and communications strategy (r = .300; p = .001) had positive bivariate associations with HRA participation rates. When all factors were included in the model, incentive value (p = .001) and communications strategy (p = .023) were significantly associated with HRA participation. Variance accounted for by all factors combined was R12 = .584. This study suggests that incentive value, incentive type, supportive worksite culture, and comprehensive communications strategy may all play a role in increasing HRA participation.

Bridging the Gap between Experts in Designing Multimedia-Based Instructional Media for Learning

ERIC Educational Resources Information Center

Razak, Rafiza Abdul

2013-01-01

The research identified and explored the cognitive knowledge among the instructional multimedia design and development experts comprising of multimedia designer, graphic designer, subject-matter expert and instructional designer. A critical need exists for a solid understanding of the factors that influence team decision making and performance in…

Multiobjective robust design of the double wishbone suspension system based on particle swarm optimization.

PubMed

Cheng, Xianfu; Lin, Yuqun

2014-01-01

The performance of the suspension system is one of the most important factors in the vehicle design. For the double wishbone suspension system, the conventional deterministic optimization does not consider any deviations of design parameters, so design sensitivity analysis and robust optimization design are proposed. In this study, the design parameters of the robust optimization are the positions of the key points, and the random factors are the uncertainties in manufacturing. A simplified model of the double wishbone suspension is established by software ADAMS. The sensitivity analysis is utilized to determine main design variables. Then, the simulation experiment is arranged and the Latin hypercube design is adopted to find the initial points. The Kriging model is employed for fitting the mean and variance of the quality characteristics according to the simulation results. Further, a particle swarm optimization method based on simple PSO is applied and the tradeoff between the mean and deviation of performance is made to solve the robust optimization problem of the double wishbone suspension system.

Shape design of an optimal comfortable pillow based on the analytic hierarchy process method

PubMed Central

Liu, Shuo-Fang; Lee, Yann-Long; Liang, Jung-Chin

2011-01-01

Objective Few studies have analyzed the shapes of pillows. The purpose of this study was to investigate the relationship between the pillow shape design and subjective comfort level for asymptomatic subjects. Methods Four basic pillow designs factors were selected on the basis of literature review and recombined into 8 configurations for testing the rank of degrees of comfort. The data were analyzed by the analytic hierarchy process method to determine the most comfortable pillow. Results Pillow number 4 was the most comfortable pillow in terms of head, neck, shoulder, height, and overall comfort. The design factors of pillow number 4 were using a combination of standard, cervical, and shoulder pillows. A prototype of this pillow was developed on the basis of the study results for designing future pillow shapes. Conclusions This study investigated the comfort level of particular users and redesign features of a pillow. A deconstruction analysis would simplify the process of determining the most comfortable pillow design and aid designers in designing pillows for groups. PMID:22654680

The Impact of Environmental Design on Teamwork and Communication in Healthcare Facilities: A Systematic Literature Review.

PubMed

Gharaveis, Arsalan; Hamilton, D Kirk; Pati, Debajyoti

2018-01-01

The purpose of this systematic review is to investigate the current knowledge about the impact of healthcare facility design on teamwork and communication by exploring the relevant literature. Teamwork and communication are behavioral factors that are impacted by physical design. However, the effects of environmental factors on teamwork and communication have not been investigated extensively in healthcare design literature. There are no published systematic reviews on the current topic. Searches were conducted in PubMed and Google Scholar databases in addition to targeted design journals including Health Environmental Research & Design, Environment and Behavior, Environmental Psychology, and Applied Ergonomics. Inclusion criteria were (a) full-text English language articles related to teamwork and communication and (b) involving any healthcare built environment and space design published in peer-reviewed journals between 1984 and 2017. Studies were extracted using defined inclusion and exclusion criteria. In the first phase, 26 of the 195 articles most relevant to teamwork and 19 studies of the 147 were identified and reviewed to understand the impact of communication in healthcare facilities. The literature regarding the impact of built environment on teamwork and communication were reviewed and explored in detail. Eighteen studies were selected and succinctly summarized as the final product of this review. Environmental design, which involves nurses, support staff, and physicians, is one of the critical factors that promotes the efficiency of teamwork and collaborative communication. Layout design, visibility, and accessibility levels are the most cited aspects of design which can affect the level of communication and teamwork in healthcare facilities.

From Human Factors to Human Actors to Human Crafters: A Meta-Design Inspired Participatory Framework for Designing in Use

ERIC Educational Resources Information Center

Maceli, Monica Grace

2012-01-01

Meta-design theory emphasizes that system designers can never anticipate all future uses of their system at design time, when systems are being developed. Rather, end users shape their environments in response to emerging needs at use time. Meta-design theory suggests that systems should therefore be designed to adapt to future conditions in the…

14 CFR 31.43 - Fitting factor.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Fitting factor. 31.43 Section 31.43... STANDARDS: MANNED FREE BALLOONS Design Construction § 31.43 Fitting factor. (a) A fitting factor of at least... structure. This factor applies to all parts of the fitting, the means of attachment, and the bearing on the...

The Unfortunate Human Factor: A Selective History of Human Factors for Technical Communicators.

ERIC Educational Resources Information Center

Johnson, Robert R.

1994-01-01

Reviews moments in the history of human factors that are especially relevant to the field of technical communications. Discusses human factors research that is applicable to technical communications. Focuses on qualitative usability research, minimalism, and human activity interface design. (HB)

Development of a prediction model for crash occurrence by analyzing traffic crash and citation data : final report.

DOT National Transportation Integrated Search

2017-04-30

It is commonly acknowledged that factors such as human factors, vehicle characteristics, road design and environmental factors highly contribute to the occurrence of traffic crashes (WHO, 2004). Since human factors usually have the most significant i...

Ultrasound-enhanced bioscouring of greige cotton: regression analysis of process factors

USDA-ARS?s Scientific Manuscript database

Process factors of enzyme concentration, time, power and frequency were investigated for ultrasound-enhanced bioscouring of greige cotton. A fractional factorial experimental design and subsequent regression analysis of the process factors were employed to determine the significance of each factor a...

The Role of Exercise Self-Efficacy, Perceived Exertion, Event-Related Stress, and Demographic Factors in Predicting Physical Activity among College Freshmen

ERIC Educational Resources Information Center

Brannagan, Kim

2011-01-01

Objectives: The focus of this study was to examine the relationship among precursors to physical activity, including exercise self-efficacy, perceived exertion, stress, and demographic factors, among college students. Design: This study employed an associational design. Setting: The study population was college freshmen in southeast Louisiana who…

Survey of piloting factors in V/STOL aircraft with implications for flight control system design

NASA Technical Reports Server (NTRS)

Ringland, R. F.; Craig, S. J.

1977-01-01

Flight control system design factors involved for pilot workload relief are identified. Major contributors to pilot workload include configuration management and control and aircraft stability and response qualities. A digital fly by wire stability augmentation, configuration management, and configuration control system is suggested for reduction of pilot workload during takeoff, hovering, and approach.

Factors Affecting the Management of Women Groups' Micro and Small Enterprises in Kakamega District, Kenya

ERIC Educational Resources Information Center

Wawire, Nelson H. W.; Nafukho, Fredrick M.

2010-01-01

Purpose: The purpose of this study is to highlight the main factors that affect the management of the WGs' Micro and Small Enterprises (MSEs) in Kakamega District and Africa in general. Design/methodology/approach: The study adopted a descriptive research design. This is because the study was concerned about a univariate question in which the…

Using Experimental Design and Data Analysis to Study the Enlisted Specialty Model for the U.S. Army G1

DTIC Science & Technology

2010-06-01

RECOMMENDATIONS FOR FUTURE STUDY ..................43 APPENDIX. OBJECTIVE FUNTION COEFFICIENTS ...................47 LIST OF REFERENCES...experiments are designed so an analyst can conduct simultaneous examination of multiple factors and explore these factors and their relationship to output...or more components. 46 THIS PAGE INTENTIONALLY LEFT BLANK 47 APPENDIX. OBJECTIVE FUNTION COEFFICIENTS

Roles of Personality, Vocational Interests, Academic Achievement and Socio-Cultural Factors in Educational Aspirations of Secondary School Adolescents in Southwestern Nigeria

ERIC Educational Resources Information Center

Salami, Samuel O.

2008-01-01

Purpose: This paper seeks to examine the roles of personality, vocational interests, academic achievement and some socio-cultural factors in educational aspirations of secondary school adolescents in southwestern Nigeria. Design/methodology/approach: A survey research design was adopted. The sample comprised 430 (males = 220, females = 210)…

From Design and Implementation to Impact of Quality Assurance: An Overview of Some Studies into What Impacts Improvement

ERIC Educational Resources Information Center

Westerheijden, Don F.; Hulpiau, Veerle; Waeytens, Kim

2007-01-01

Attention shifted in recent years from design and implementation to use and usefulness of quality assurance. Scientific studies focus increasingly on quality assurance's impact on curricula and individual teachers. Which factors influence follow-up activities and what is their relation to improvement of education? One factor that we single out is…

Human Factors Design Criteria for Future Systems. FAADS Design Criteria Evolving from the Sgt. York Follow-On Evaluation 1

DTIC Science & Technology

1989-05-01

and MIL-., TD -11172C. These are the most widely used documents providing human factors design criteria for the development of military systems through...4) 4bd 4)(.E c4- z - v -. r-f .r40 m 0 S -( OD Q) 0k .1 .o1 u .d 44). o- C.~) V QCf 44)) :0 J0 Al4 L .4Uv.-4 C4)LI.-44(U(E *4)4)( U . S- M 0 a *-P 4

Human Factors in Accidents Involving Remotely Piloted Aircraft

NASA Technical Reports Server (NTRS)

Merlin, Peter William

2013-01-01

This presentation examines human factors that contribute to RPA mishaps and provides analysis of lessons learned. RPA accident data from U.S. military and government agencies were reviewed and analyzed to identify human factors issues. Common contributors to RPA mishaps fell into several major categories: cognitive factors (pilot workload), physiological factors (fatigue and stress), environmental factors (situational awareness), staffing factors (training and crew coordination), and design factors (human machine interface).

[Analysing the defect of control design of acupuncture: taking RCTs of treating simple obesity with acupuncture for example].

PubMed

Zeng, Yi; Qi, Shulan; Meng, Xing; Chen, Yinyin

2018-03-12

By analysing the defect of control design in randomized controlled trials (RCTs) of simple obesity treated with acupuncture and using acupuncture as the contrast, presenting the essential factors which should be taken into account as designing the control of clinical trial to further improve the clinical research. Setting RCTs of acupuncture treating simple obesity as a example, we searched RCTs of acupuncture treating simple obesity with acupuncture control. According to the characteristics of acupuncture therapy, this research sorted and analysed the control approach of intervention from aspects of acupoint selection, the penetration of needle, the depth of insertion, etc, then calculated the amount of difference factor between the two groups and analyzed the rationality. In 15 RCTs meeting the inclusion criterias, 7 published in English, 8 in Chinese, the amount of difference factors between two groups greater than 1 was 6 (40%), 4 published in English abroad, 2 in Chinese, while only 1 was 9 (60%), 3 published in English, 6 in Chinese. Control design of acupuncture in some clinical RCTs is unreasonable for not considering the amount of difference factors between the two groups.

Performance-based design factors for pile foundations.

DOT National Transportation Integrated Search

2014-10-01

The seismic design of pile foundations is currently performed in a relatively simple, deterministic manner. This : report describes the development of a performance-based framework to create seismic designs of pile group : foundations that consider a...

Omitted variable bias in crash reduction factors.

DOT National Transportation Integrated Search

2015-09-01

Transportation planners and traffic engineers are increasingly turning to crash reduction factors to evaluate changes in road : geometric and design features in order to reduce crashes. Crash reduction factors are typically estimated based on segment...

Design of admission medication reconciliation technology: a human factors approach to requirements and prototyping.

PubMed

Lesselroth, Blake J; Adams, Kathleen; Tallett, Stephanie; Wood, Scott D; Keeling, Amy; Cheng, Karen; Church, Victoria L; Felder, Robert; Tran, Hanna

2013-01-01

Our objectives were to (1) develop an in-depth understanding of the workflow and information flow in medication reconciliation, and (2) design medication reconciliation support technology using a combination of rapid-cycle prototyping and human-centered design. Although medication reconciliation is a national patient safety goal, limitations both of physical environment and in workflow can make it challenging to implement durable systems. We used several human factors techniques to gather requirements and develop a new process to collect a medication history at hospital admission. We completed an ethnography and time and motion analysis of pharmacists in order to illustrate the processes used to reconcile medications. We then used the requirements to design prototype multimedia software for collecting a bedside medication history. We observed how pharmacists incorporated the technology into their physical environment and documented usability issues. Admissions occurred in three phases: (1) list compilation, (2) order processing, and (3) team coordination. Current medication reconciliation processes at the hospital average 19 minutes to complete and do not include a bedside interview. Use of our technology during a bedside interview required an average of 29 minutes. The software represents a viable proof-of-concept to automate parts of history collection and enhance patient communication. However, we discovered several usability issues that require attention. We designed a patient-centered technology to enhance how clinicians collect a patient's medication history. By using multiple human factors methods, our research team identified system themes and design constraints that influence the quality of the medication reconciliation process and implementation effectiveness of new technology. Evidence-based design, human factors, patient-centered care, safety, technology.

The use of modified scaling factors in the design of high-power, non-linear, transmitting rod-core antennas

NASA Astrophysics Data System (ADS)

Jordan, Jared Williams; Dvorak, Steven L.; Sternberg, Ben K.

2010-10-01

In this paper, we develop a technique for designing high-power, non-linear, transmitting rod-core antennas by using simple modified scale factors rather than running labor-intensive numerical models. By using modified scale factors, a designer can predict changes in magnetic moment, inductance, core series loss resistance, etc. We define modified scale factors as the case when all physical dimensions of the rod antenna are scaled by p, except for the cross-sectional area of the individual wires or strips that are used to construct the core. This allows one to make measurements on a scaled-down version of the rod antenna using the same core material that will be used in the final antenna design. The modified scale factors were derived from prolate spheroidal analytical expressions for a finite-length rod antenna and were verified with experimental results. The modified scaling factors can only be used if the magnetic flux densities within the two scaled cores are the same. With the magnetic flux density constant, the two scaled cores will operate with the same complex permeability, thus changing the non-linear problem to a quasi-linear problem. We also demonstrate that by holding the number of turns times the drive current constant, while changing the number of turns, the inductance and core series loss resistance change by the number of turns squared. Experimental measurements were made on rod cores made from varying diameters of black oxide, low carbon steel wires and different widths of Metglas foil. Furthermore, we demonstrate that the modified scale factors work even in the presence of eddy currents within the core material.

Work design and management in the manufacturing sector: development and validation of the Work Organisation Assessment Questionnaire.

PubMed

Griffiths, A; Cox, T; Karanika, M; Khan, S; Tomás, J M

2006-10-01

To examine the factor structure, reliability, and validity of a new context-specific questionnaire for the assessment of work and organisational factors. The Work Organisation Assessment Questionnaire (WOAQ) was developed as part of a risk assessment and risk reduction methodology for hazards inherent in the design and management of work in the manufacturing sector. Two studies were conducted. Data were collected from 524 white- and blue-collar employees from a range of manufacturing companies. Exploratory factor analysis was carried out on 28 items that described the most commonly reported failures of work design and management in companies in the manufacturing sector. Concurrent validity data were also collected. A reliability study was conducted with a further 156 employees. Principal component analysis, with varimax rotation, revealed a strong 28-item, five factor structure. The factors were named: quality of relationships with management, reward and recognition, workload, quality of relationships with colleagues, and quality of physical environment. Analyses also revealed a more general summative factor. Results indicated that the questionnaire has good internal consistency and test-retest reliability and validity. Being associated with poor employee health and changes in health related behaviour, the WOAQ factors are possible hazards. It is argued that the strength of those associations offers some estimation of risk. Feedback from the organisations involved indicated that the WOAQ was easy to use and meaningful for them as part of their risk assessment procedures. The studies reported here describe a model of the hazards to employee health and health related behaviour inherent in the design and management of work in the manufacturing sector. It offers an instrument for their assessment. The scales derived which form the WOAQ were shown to be reliable, valid, and meaningful to the user population.

2014 Space Human Factors Engineering Standing Review Panel

NASA Technical Reports Server (NTRS)

Steinberg, Susan

2014-01-01

The 2014 Space Human Factors Engineering (SHFE) Standing Review Panel (from here on referred to as the SRP) participated in a WebEx/teleconference with members of the Space Human Factors and Habitability (SHFH) Element, representatives from the Human Research Program (HRP), the National Space Biomedical Research Institute (NSBRI), and NASA Headquarters on November 17, 2014 (list of participants is in Section XI of this report). The SRP reviewed the updated research plans for the Risk of Incompatible Vehicle/Habitat Design (HAB Risk) and the Risk of Performance Errors Due to Training Deficiencies (Train Risk). The SRP also received a status update on the Risk of Inadequate Critical Task Design (Task Risk), the Risk of Inadequate Design of Human and Automation/Robotic Integration (HARI Risk), and the Risk of Inadequate Human-Computer Interaction (HCI Risk).

Collaborating with human factors when designing an electronic textbook

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ratner, J.A.; Zadoks, R.I.; Attaway, S.W.

The development of on-line engineering textbooks presents new challenges to authors to effectively integrate text and tools in an electronic environment. By incorporating human factors principles of interface design and cognitive psychology early in the design process, a team at Sandia National Laboratories was able to make the end product more usable and shorten the prototyping and editing phases. A critical issue was simultaneous development of paper and on-line versions of the textbook. In addition, interface consistency presented difficulties with distinct goals and limitations for each media. Many of these problems were resolved swiftly with human factors input using templates,more » style guides and iterative usability testing of both paper and on-line versions. Writing style continuity was also problematic with numerous authors contributing to the text.« less

Comparative effectiveness of colony-stimulating factors in febrile neutropenia prophylaxis: how results are affected by research design.

PubMed

Henk, Henry J; Li, Xiaoyan; Becker, Laura K; Xu, Hairong; Gong, Qi; Deeter, Robert G; Barron, Richard L

2015-01-01

To examine the impact of research design on results in two published comparative effectiveness studies. Guidelines for comparative effectiveness research have recommended incorporating disease process in study design. Based on the recommendations, we develop a checklist of considerations and apply the checklist in review of two published studies on comparative effectiveness of colony-stimulating factors. Both studies used similar administrative claims data, but different methods, which resulted in directionally different estimates. Major design differences between the two studies include: whether the timing of intervention in disease process was identified and whether study cohort and outcome assessment period were defined based on this temporal relationship. Disease process and timing of intervention should be incorporated into the design of comparative effectiveness studies.

Simplified Design Method for Tension Fasteners

NASA Astrophysics Data System (ADS)

Olmstead, Jim; Barker, Paul; Vandersluis, Jonathan

2012-07-01

Tension fastened joints design has traditionally been an iterative tradeoff between separation and strength requirements. This paper presents equations for the maximum external load that a fastened joint can support and the optimal preload to achieve this load. The equations, based on linear joint theory, account for separation and strength safety factors and variations in joint geometry, materials, preload, load-plane factor and thermal loading. The strength-normalized versions of the equations are applicable to any fastener and can be plotted to create a "Fastener Design Space", FDS. Any combination of preload and tension that falls within the FDS represents a safe joint design. The equation for the FDS apex represents the optimal preload and load capacity of a set of joints. The method can be used for preliminary design or to evaluate multiple pre-existing joints.

Human Factors Guidance for Control Room and Digital Human-System Interface Design and Modification, Guidelines for Planning, Specification, Design, Licensing, Implementation, Training, Operation and Maintenance

DOE Office of Scientific and Technical Information (OSTI.GOV)

R. Fink, D. Hill, J. O'Hara

2004-11-30

Nuclear plant operators face a significant challenge designing and modifying control rooms. This report provides guidance on planning, designing, implementing and operating modernized control rooms and digital human-system interfaces.

Design and performance of an 0.8 hub-tip ratio axial flow pump rotor with a blade tip diffusion factor of 0.55

NASA Technical Reports Server (NTRS)

Urasek, D. C.

1972-01-01

A 22.9-centimeter diameter axial flow rotor with a 0.8 hub-tip radius ratio, a design flow coefficient of 0.466, and a blade tip design diffusion factor of 0.55 was tested in cold water under both cavitating and noncavitating conditions. Radial surveys of the flow conditions at the rotor inlet and outlet were made. At design flow, the rotor produced an overall headrise coefficient of 0.360 with an overall efficiency of 95.0 percent. The efficiency remained greater than 88 percent over the entire flow coefficient range which varied from 0.350 to 0.615.

Development of low-level liquid-waste-treatment systems, October 1981 - March 1982

NASA Astrophysics Data System (ADS)

Williams, M. K.; Colvin, C. M.

1982-05-01

A plant design for a reverse osmosis (RO) membrane unit was completed. The design includes a conceptual diagram, specifications for a RO unit producing 40 gal/min of permeated product, a list of radioisotopes tested on RO units and the rejections achieved, a discussion of the principle of RO, a discussion of the upper limits of cation and anion concentrations (there are no lower limits), a discussion of membrane configurations and porosities, a discussion of factors affecting membranes, a section on calculating the membrane area needed for a particular application, and capital and operating cost calculations. The three factors found to affect the adsorption of cobalt on ion exchange resins were investigated in an interaction effects design experiment. These factors are solution pH, and sulfite and ammonium concentrations. Greater than 99% of the cobalt can usually be removed from solutions at a pH between 3 and 6. A design for an ion-exchange pilot plant was completed.

Denoising Sparse Images from GRAPPA using the Nullspace Method (DESIGN)

PubMed Central

Weller, Daniel S.; Polimeni, Jonathan R.; Grady, Leo; Wald, Lawrence L.; Adalsteinsson, Elfar; Goyal, Vivek K

2011-01-01

To accelerate magnetic resonance imaging using uniformly undersampled (nonrandom) parallel imaging beyond what is achievable with GRAPPA alone, the Denoising of Sparse Images from GRAPPA using the Nullspace method (DESIGN) is developed. The trade-off between denoising and smoothing the GRAPPA solution is studied for different levels of acceleration. Several brain images reconstructed from uniformly undersampled k-space data using DESIGN are compared against reconstructions using existing methods in terms of difference images (a qualitative measure), PSNR, and noise amplification (g-factors) as measured using the pseudo-multiple replica method. Effects of smoothing, including contrast loss, are studied in synthetic phantom data. In the experiments presented, the contrast loss and spatial resolution are competitive with existing methods. Results for several brain images demonstrate significant improvements over GRAPPA at high acceleration factors in denoising performance with limited blurring or smoothing artifacts. In addition, the measured g-factors suggest that DESIGN mitigates noise amplification better than both GRAPPA and L1 SPIR-iT (the latter limited here by uniform undersampling). PMID:22213069

Designing Printed Instructional Materials.

ERIC Educational Resources Information Center

Burbank, Lucille; Pett, Dennis

1986-01-01

Discusses the importance of identifying the audience and determining specific objectives when designing printed instructional materials that will communicate effectively and provides detailed guidelines for dealing with such design factors as content, writing style, typography, illustrations, and page organization. (MBR)

Soil-cement design study : interim report No. 1.

DOT National Transportation Integrated Search

1971-05-01

Soil-cement base course materials design in Louisiana is based upon durability and compressive strength criteria, with the compressive strength requirements being the controlling factor in 95 percent of the designs. The findings to data have provided...

GPS User-Interface Design Problems

DOT National Transportation Integrated Search

1999-04-01

This paper is a review of human factors problems associated with the user-interface design of a set of Global Positioning : System (GPS) receivers, certified for use in aircraft for instrument non-precision approaches. The paper focuses on : design p...

Correlation of causal factors that influence construction safety performance: A model.

PubMed

Rodrigues, F; Coutinho, A; Cardoso, C

2015-01-01

The construction sector has presented positive development regarding the decrease in occupational accident rates in recent years. Regardless, the construction sector stands out systematically from other industries due to its high number of fatalities. The aim of this paper is to deeply understand the causality of construction accidents from the early design phase through a model. This study reviewed several research papers presenting various analytical models that correlate the contributing factors to occupational accidents in this sector. This study also analysed different construction projects and conducted a survey of design and site supervision teams. This paper proposes a model developed from the analysis of existing ones, which correlates the causal factors through all the construction phases. It was concluded that effective risk prevention can only be achieved by a global correlation of causal factors including not only production ones but also client requirements, financial climate, design team competence, project and risk management, financial capacity, health and safety policy and early planning. Accordingly, a model is proposed.

Usable Interface Design for Everyone

NASA Astrophysics Data System (ADS)

de Castro Lozano, Carlos; Salcines, Enrique García; Sainz de Abajo, Beatriz; Burón Fernández, F. Javier; Ramírez, José Miguel; Recellado, José Gabriel Zato; Montoya, Rafael Sanchez; Bell, John; Marin, Francisco Alcantud

When designing "interfaces for everyone" for interactive systems, it is important to consider factors such as cost, the intended market, the state of the environment, etc. User interfaces are fundamental for the developmental process in any application, and its design must be contemplated from the start. Of the distinct parts of a system (hardware and software), it is the interface that permits the user access to computer resources. The seven principles of "Universal Design" or "Design for Everyone" focus on a universal usable design, but at the same time acknowledge the influences of internal and external factors. Structural changes in social and health services could provide an increase in the well-being of a country's citizens through the use of self-care programming and proactive management/prevention of disease. Automated home platforms can act as an accessibility instrument which permits users to avoid, compensate, mitigate, or neutralize the deficiencies and dependencies caused by living alone.

Towards Universal Design Hotels in Denmark.

PubMed

Grangaard, Sidse

2016-01-01

Based on the research project 'Accessible Hotel Rooms' that studies the balance between the experience of supply and demand regarding accessibility features in Danish hotel rooms, this paper demonstrates factors having an influence on Universal Design hotels in Denmark. The research project was financed by the Danish Transport and Construction Agency. Different notions in the hotel sector of the current supply and demand for Universal Design hotel rooms are identified, as well as future demand. Despite supplying accessible rooms, some hotels do not advertise their accessibility features on their website. There exists an attitude in the hotel sector that functions as a barrier for Universal Design: if there are enough guests, for example business travellers, then why market the hotel on Universal Design? The paper points out the coherence between the understanding of the users and the view of demand. Another important factor is Corporate Social Responsibility, which can be regarded as a strategy or platform towards Universal Design hotels.

Multi-function displays : a guide for human factors evaluation.

DOT National Transportation Integrated Search

2013-11-01

This guide is designed to assist aircraft certification personnel and avionics : manufacturers in evaluating the human factors aspects of Multi-function Displays : (MFDs) for FAA certification. The guide focuses specifically on human factors and : do...

Design of psychosocial factors questionnaires: a systematic measurement approach

PubMed Central

Vargas, Angélica; Felknor, Sarah A

2012-01-01

Background Evaluation of psychosocial factors requires instruments that measure dynamic complexities. This study explains the design of a set of questionnaires to evaluate work and non-work psychosocial risk factors for stress-related illnesses. Methods The measurement model was based on a review of literature. Content validity was performed by experts and cognitive interviews. Pilot testing was carried out with a convenience sample of 132 workers. Cronbach’s alpha evaluated internal consistency and concurrent validity was estimated by Spearman correlation coefficients. Results Three questionnaires were constructed to evaluate exposure to work and non-work risk factors. Content validity improved the questionnaires coherence with the measurement model. Internal consistency was adequate (α=0.85–0.95). Concurrent validity resulted in moderate correlations of psychosocial factors with stress symptoms. Conclusions Questionnaires´ content reflected a wide spectrum of psychosocial factors sources. Cognitive interviews improved understanding of questions and dimensions. The structure of the measurement model was confirmed. PMID:22628068

The effect of job and environmental factors on job satisfaction in automotive industries.

PubMed

Dawal, Siti Zawiah Md; Taha, Zahari

2006-01-01

A methodology was developed for diagnosing industrial work, which includes questionnaire, observation, measurements, data collection and statistical analysis. A survey was conducted to investigate the relationship between job satisfaction and factors that affect work design in 2 automotives manufacturing companies in Malaysia. A basic work design model was proposed. The aim of this model was to determine the factors that influence employees' perception towards their work. A set of multiple-choice questionnaires was developed and data was collected by interviewing employees at a production plant. The survey focused on job and environmental factors. The results supported the proposed model and showed that job and environmental factors were significantly related to job satisfaction. They highlighted the significant influence of age, work experience and marital status on job satisfaction. Further, environmental factors, especially the surroundings, context dependence and the building's function, also had a significant impact on job satisfaction.

Do we need sustainability as a new approach in human factors and ergonomics?

PubMed

Zink, Klaus J; Fischer, Klaus

2013-01-01

The International Ergonomics Association Technical Committee 'Human Factors and Sustainable Development' was established to contribute to a broad discourse about opportunities and risks resulting from current societal 'mega-trends' and their impacts on the interactions among humans and other elements of a system, e.g. in work systems. This paper focuses on the underlying key issues: how do the sustainability paradigm and human factors/ergonomics interplay and interact, and is sustainability necessary as a new approach for our discipline? Based on a discussion of the sustainability concept, some general principles for designing new and enhancing existent approaches of human factors and ergonomics regarding their orientation towards sustainability are proposed. The increasing profile of sustainability on the international stage presents new opportunities for human factors/ergonomics. Positioning of the sustainability paradigm within human factors/ergonomics is discussed. Approaches to incorporating sustainability in the design of work systems are considered.

Measuring and Advancing Experimental Design Ability in an Introductory Course without Altering Existing Lab Curriculum†

PubMed Central

Shanks, Ryan A.; Robertson, Chuck L.; Haygood, Christian S.; Herdliksa, Anna M.; Herdliska, Heather R.; Lloyd, Steven A.

2017-01-01

Introductory biology courses provide an important opportunity to prepare students for future courses, yet existing cookbook labs, although important in their own way, fail to provide many of the advantages of semester-long research experiences. Engaging, authentic research experiences aid biology students in meeting many learning goals. Therefore, overlaying a research experience onto the existing lab structure allows faculty to overcome barriers involving curricular change. Here we propose a working model for this overlay design in an introductory biology course and detail a means to conduct this lab with minimal increases in student and faculty workloads. Furthermore, we conducted exploratory factor analysis of the Experimental Design Ability Test (EDAT) and uncovered two latent factors which provide valid means to assess this overlay model’s ability to increase advanced experimental design abilities. In a pre-test/post-test design, we demonstrate significant increases in both basic and advanced experimental design abilities in an experimental and comparison group. We measured significantly higher gains in advanced experimental design understanding in students in the experimental group. We believe this overlay model and EDAT factor analysis contribute a novel means to conduct and assess the effectiveness of authentic research experiences in an introductory course without major changes to the course curriculum and with minimal increases in faculty and student workloads. PMID:28904647

An Architecture for Designing Content Agnostic Game Mechanics for Educational Burst Games

ERIC Educational Resources Information Center

Baron, Tyler

2017-01-01

Currently, educational games are designed with the educational content as the primary factor driving the design of the game. While this may seem to be the optimal approach, this design paradigm causes multiple issues. For one, the games themselves are often not engaging as game design principles were put aside in favor of increasing the…

Assessing Reflective Thinking in Solving Design Problems: The Development of a Questionnaire

ERIC Educational Resources Information Center

Hong, Yi-Chun; Choi, Ikseon

2015-01-01

Reflection is a critical factor in solving design problems. Using good methods to observe designers' reflection is essential to inform the design of the learning environments that support the development of design problem-solving skills. In this study, we have developed and validated a novel self-reporting questionnaire as an efficient instrument…

Generalized Subset Designs in Analytical Chemistry.

PubMed

Surowiec, Izabella; Vikström, Ludvig; Hector, Gustaf; Johansson, Erik; Vikström, Conny; Trygg, Johan

2017-06-20

Design of experiments (DOE) is an established methodology in research, development, manufacturing, and production for screening, optimization, and robustness testing. Two-level fractional factorial designs remain the preferred approach due to high information content while keeping the number of experiments low. These types of designs, however, have never been extended to a generalized multilevel reduced design type that would be capable to include both qualitative and quantitative factors. In this Article we describe a novel generalized fractional factorial design. In addition, it also provides complementary and balanced subdesigns analogous to a fold-over in two-level reduced factorial designs. We demonstrate how this design type can be applied with good results in three different applications in analytical chemistry including (a) multivariate calibration using microwave resonance spectroscopy for the determination of water in tablets, (b) stability study in drug product development, and (c) representative sample selection in clinical studies. This demonstrates the potential of generalized fractional factorial designs to be applied in many other areas of analytical chemistry where representative, balanced, and complementary subsets are required, especially when a combination of quantitative and qualitative factors at multiple levels exists.

On the Accuracy of Probabilistic Bucking Load Prediction

NASA Technical Reports Server (NTRS)

Arbocz, Johann; Starnes, James H.; Nemeth, Michael P.

2001-01-01

The buckling strength of thin-walled stiffened or unstiffened, metallic or composite shells is of major concern in aeronautical and space applications. The difficulty to predict the behavior of axially compressed thin-walled cylindrical shells continues to worry design engineers as we enter the third millennium. Thanks to extensive research programs in the late sixties and early seventies and the contributions of many eminent scientists, it is known that buckling strength calculations are affected by the uncertainties in the definition of the parameters of the problem such as definition of loads, material properties, geometric variables, edge support conditions, and the accuracy of the engineering models and analysis tools used in the design phase. The NASA design criteria monographs from the late sixties account for these design uncertainties by the use of a lump sum safety factor. This so-called 'empirical knockdown factor gamma' usually results in overly conservative design. Recently new reliability based probabilistic design procedure for buckling critical imperfect shells have been proposed. It essentially consists of a stochastic approach which introduces an improved 'scientific knockdown factor lambda(sub a)', that is not as conservative as the traditional empirical one. In order to incorporate probabilistic methods into a High Fidelity Analysis Approach one must be able to assess the accuracy of the various steps that must be executed to complete a reliability calculation. In the present paper the effect of size of the experimental input sample on the predicted value of the scientific knockdown factor lambda(sub a) calculated by the First-Order, Second-Moment Method is investigated.

Firefighting to Innovation: Using Human Factors and Ergonomics to Tackle Slip, Trip, and Fall Risks in Hospitals.

PubMed

Hignett, Sue; Wolf, Laurie; Taylor, Ellen; Griffiths, Paula

2015-11-01

The aim of this study was to use a theoretical model (bench) for human factors and ergonomics (HFE) and a comparison with occupational slips, trips, and falls (STFs) risk management to discuss patient STF interventions (bedside). Risk factors for patient STFs have been identified and reported since the 1950s and are mostly unchanged in the 2010s. The prevailing clinical view has been that STF events indicate underlying frailty or illness, and so many of the interventions over the past 60 years have focused on assessing and treating physiological factors (dizziness, illness, vision/hearing, medicines) rather than designing interventions to reduce risk factors at the time of the STF. Three case studies are used to discuss how HFE has been, or could be, applied to STF risk management as (a) a design-based (building) approach to embed safety into the built environment, (b) a staff- (and organization-) based approach, and (c) a patient behavior-based approach to explore and understand patient perspectives of STF events. The results from the case studies suggest taking a similar HFE integration approach to other industries, that is, a sustainable design intervention for the person who experiences the STF event-the patient. This paper offers a proactive problem-solving approach to reduce STFs by patients in acute hospitals. Authors of the three case studies use HFE principles (bench/book) to understand the complex systems for facility and equipment design and include the perspective of all stakeholders (bedside). © 2015, Human Factors and Ergonomics Society.

NASA Human Integration Design Handbook (HIDH): Revitalization of Space-Related Human Factors, Environmental, and Habitability Data and Design Guidance

NASA Technical Reports Server (NTRS)

Stroud, Kenneth; Pickett, Lynn; Tillman, Barry

2008-01-01

This poster presentation reviews the Human Integration Design Handbook (HIDH). It provides guidance and data to aid vehicle / habitat designers in human-system integration It also aids requirements writers in development of human-system integration requirements from SFHSS Standards

So, Just Select Some Furniture....

ERIC Educational Resources Information Center

Michaels, David L.

1995-01-01

Discusses factors that affect the process of furnishing a library: different areas require different designs, patron demand for aesthetic design, laws governing furniture choice, incorporating technology into design, and the need for market appeal. A list of design criteria is provided to aid in selecting library furniture and an appendix lists…

The effect of environmental factors on the implementation of the Mechanistic-empirical pavement design guide (MEPDG).

DOT National Transportation Integrated Search

2011-07-01

Current pavement design based on the AASHTO Design Guide uses an empirical approach from the results of the AASHO Road Test conducted in 1958. To address some of the limitations of the original design guide, AASHTO developed a new guide: Mechanistic ...

Effects of Screen Designs in CBI Environments.

ERIC Educational Resources Information Center

Ikegulu, Patricia R.

This article focuses on the effectiveness of computer-based instruction (CBI) screen designs, including their benefits and limitations, as well as human constraints in designing effective CBI. The paper begins with an overview of what comprises an effective CBI screen design, including characteristics of human factors, how information must be…

Development of Design Expertise by Architecture Students

ERIC Educational Resources Information Center

Oluwatayo, Adedapo Adewunmi; Ezema, Isidore; Opoko, Akunnaya

2017-01-01

What constitutes design ability and design expertise in architecture? Which categories of design expertise can be identified amongst architecture students? And which input factors differentiate one level of expertise from another? These questions were addressed in a survey of architecture students in Nigeria. Based on the results, students were…

Understanding Decision Making in Teachers' Curriculum Design Approaches

ERIC Educational Resources Information Center

Boschman, Ferry; McKenney, Susan; Voogt, Joke

2014-01-01

The goal of this study was to reach a better understanding of the intuitive decisions teachers make when designing a technology-rich learning environment. A multiple case-study design was employed to examine what kinds of factors (external priorities, existing orientations or practical concerns) influence design interactions of teams of…

Afro-Caribbean and African American Students, Family Factors, and the Influence on Science Performance in the United States: The Untold Story

ERIC Educational Resources Information Center

Pinder, Patrice Juliet

2012-01-01

The primary objectives of this research were to explore achievement pattern differences and the influence of family factors on the achievement patterns of Afro-Caribbean and African American students within the United States (U.S.). The study utilized two research designs; a causal-comparative and a correlational design. A student family…