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1

Fuzzy QSARs for predicting logKoc of persistent organic pollutants.  

PubMed

Fuzzy regression methodology has been employed in this study to develop a relationship for logKoc for persistent organic pollutants (POPs) using other property and molecular descriptors. Fuzzy regression is distinct from statistical regression and is used to characterize the imprecision arising from limited data and/or incomplete model descriptions. The study is based on the premise that statistically based QSARs do not fully account for all the sorbate-sorbent interactions pertinent to the partitioning of POPs and as such these relationships have inherent fuzziness associated with them. A comparison between the statistical and fuzzy logKow-logKoc relationship indicated that the fuzzy regression model enveloped all scatter in the data and provided a tighter fit around the mid-point values (least-square estimates). In addition, fuzzy regression was also employed to characterize imprecision associated with a three parameter QSAR that employs molecular connectivity indicies. A comparison between fuzzy and statistical regression analysis indicated that the fuzziness in this model was primarily associated with characterization of local (atomic) scale interactions while statistical randomness manifested at both local and global (molecular) scales. Experimental and estimation artifacts appear to have a higher impact on statistical regression than fuzzy regression. However, the superiority of the fuzzy regression seems to diminish with increasing correlation between the inputs and the output variable. PMID:14602110

Uddameri, Venkatesh; Kuchanur, Muthukumar

2004-02-01

2

Dissolved Concentrations of PAHs and PCBs Are Often Over-predicted Using Sediment Concentrations and Literature Koc Values  

EPA Science Inventory

There is an increasing amount of chemical and biological evidence that using sediment concentrations and commonly applied Koc values frequently overpredicts interstitial water concentrations of HOCs, and thereby overestimates uptake and/or effects of those chemicals on exposed or...

3

LFERs for soil organic carbon-water distribution coefficients (Koc) at environmentally relevant sorbate concentrations.  

PubMed

Organic carbon-water distribution coefficients, Koc, for organic compounds at environmentally relevant, low sorbate concentrations may substantially differ from those at higher concentrations due to nonlinear sorption to soil organic matter. However, prediction methods for Koc such as linear free energy relationships (LFERs) are currently only available for high sorbate concentrations (i.e., near solubility limits), reflecting the lack of a set of consistent experimental data in an environmentally more relevant concentration range (i.e., orders of magnitude lower than solubilities). In this study, we determined Koc for two model sorbents of soil organic matter, peat and lignite, at sorbate concentrations of 4.3 and 19 mg/kg-organic-carbon, respectively, in batch suspensions. The measured Koc values for organic sorbates (51 for peat, 58 for lignite) of varying sizes and polarities were modeled successfully with polyparameter linear free energy relationships (PP-LFERs). The resulting PP-LFER for peat was significantly different from the PP-LFERs in the literature determined at near aqueous solubility limits of sorbates. The literature PP-LFERs were found to underestimate the measured Koc values for peat at the low concentration by up to 1 order of magnitude. The extent of underestimation highly depends on the sorbate properties and can be explained by differing sorption nonlinearities of the sorbates as predicted by a reported empirical relationship between the nonlinearity in peat and the sorbate dipolarity/polarizability parameter S. Lignite appearsto be a stronger sorbent toward many sorbates than typical soil organic matter irrespective of the concentration range and thus may not be representative for organic matter with regard to the magnitude of Koc. The present study offers the first PP-LFER equation for log Koc in soil organic matter at typical environmental sorbate concentrations. PMID:19534119

Endo, Satoshi; Grathwohl, Peter; Haderlein, Stefan B; Schmidt, Torsten C

2009-05-01

4

The effect of different log P algorithms on the modeling of the soil sorption coefficient of nonionic pesticides.  

PubMed

Collecting data on the effects of pesticides on the environment is a slow and costly process. Therefore, significant efforts have been focused on the development of models that predict physical, chemical or biological properties of environmental interest. The soil sorption coefficient normalized to the organic carbon content (Koc) is a key parameter that is used in environmental risk assessments. Thus, several log Koc prediction models that use the hydrophobic parameter log P as a descriptor have been reported in the literature. Often, algorithms are used to calculate the value of log P due to the lack of experimental values for this property. Despite the availability of various algorithms, previous studies fail to describe the procedure used to select the appropriate algorithm. In this study, models that correlate log Koc with log P were developed for a heterogeneous group of nonionic pesticides using different freeware algorithms. The statistical qualities and predictive power of all of the models were evaluated. Thus, this study was conducted to assess the effect of the log P algorithm choice on log Koc modeling. The results clearly demonstrate that the lack of a selection criterion may result in inappropriate prediction models. Seven algorithms were tested, of which only two (ALOGPS and KOWWIN) produced good results. A sensible choice may result in simple models with statistical qualities and predictive power values that are comparable to those of more complex models. Therefore, the selection of the appropriate log P algorithm for modeling log Koc cannot be arbitrary but must be based on the chemical structure of compounds and the characteristics of the available algorithms. PMID:23886539

Dos Reis, Ralpho Rinaldo; Sampaio, Silvio César; de Melo, Eduardo Borges

2013-07-05

5

Informal Undergraduate Polymer Research Program at Koc University Chemistry Department  

Microsoft Academic Search

Koc University (KU) is a private, non-profit university established in 1993 and is located on the European side of Istanbul, Turkey. The Chemistry Department accepts 12 freshmen every year, 8 with full, 4 with half merit-scholarships. Students accepted rank in the top 2% of Turkish high school graduates. Students participate in research activities starting their freshman years. Polymer research group

Iskender Yilgor; Emel Yilgor

2008-01-01

6

The high value of logged tropical forests: lessons from northern Borneo  

Microsoft Academic Search

The carbon storage and conservation value of old-growth tropical forests is clear, but the value of logged forest is less\\u000a certain. Here we analyse >100,000 observations of individuals from 11 taxonomic groups and >2,500 species, covering up to\\u000a 19 years of post-logging regeneration, and quantify the impacts of logging on carbon storage and biodiversity within lowland\\u000a dipterocarp forests of Sabah, Borneo.

Nicholas J. Berry; Oliver L. Phillips; Simon L. Lewis; Jane K. Hill; David P. Edwards; Noel B. Tawatao; Norhayati Ahmad; David Magintan; Chey V. Khen; M. Maryati; Robert C. Ong; Keith C. Hamer

2010-01-01

7

The value of rehabilitating logged rainforest for birds.  

PubMed

The recent advent of carbon crediting has led to a rapid rise in biosequestration projects that seek to remove carbon from the atmosphere through afforestation and forest rehabilitation. Such projects also present an important potential opportunity to reverse biodiversity losses resulting from deforestation and forest degradation, but the biodiversity benefits of different forms of biosequestration have not been considered adequately. We captured birds in mist nets to examine the effects of rehabilitation of logged forest on birds in Sabah, Borneo, and to test the hypothesis that rehabilitation restores avian assemblages within regenerating forest to a condition closer to that seen in unlogged forest. Species richness and diversity were similar in unlogged and rehabilitated forest, but significantly lower in naturally regenerating forest. Rehabilitation resulted in a relatively rapid recovery of populations of insectivores within logged forest, especially those species that forage by sallying, but had a marked adverse effect on frugivores and possibly reduced the overall abundance of birds within regenerating forest. In view of these results, we advocate increased management for heterogeneity within rehabilitated forests, but we strongly urge an increased role for forest rehabilitation in the design and implementation of a biodiversity-friendly carbon-offsetting market. PMID:19775274

Edwards, David P; Ansell, Felicity A; Ahmad, Abdul H; Nilus, Reuben; Hamer, Keith C

2009-09-22

8

Logging system adds value to field rejuvenation efforts  

SciTech Connect

As with any rejuvenation scheme, the first step is always identification and evaluation of potential producible reserves. But economic and physical factors made evaluation using traditional logging techniques problematic. The constraints that inhibited earlier logging tools have been addressed by a new, compact integrated system called Platform Express (PEX). Oil companies operating in two of the most mature producing regions of the US, the Hugoton-Panhandle Field and the Southwest Nena Lucia Field in West Texas, discuss the physical and economic advantages they are reaping using PEX technologies. Hugoton-Panhandle Field, discovered around 1920, sprawls across parts of three south-central states and has been one of the world`s largest gas producers. Despite continuing pressure declines in this aging gas giant, the entire region has undergone restoration in the last few years. In its Kansas portions, a modest oil production has almost doubled since 1990 and a steep gas decline has been completely turned around. These production gains have come from an active program of recompletions, the deepening of old holes and new drilling. The story in the southwest Nena Lucia Field is much the same. Operator Oryx Energy has been active in the field, located west of Abilene, Texas, since its discovery in the 1950s. The goal with this field is to use advanced technologies to reverse the production declines that began years ago. Such a reversal began in mid-1996 and has been sustained thus far.

Peters, D.; Bartenhagen, K. [Schlumberger Wireline and Testing, Sugar Land, TX (United States); Santolamazza, A. [Schlumberger Wireline and Testing, Liberal, KS (United States)

1997-11-01

9

Use of well logs to provide formation design values for hydraulic fracture treatments  

SciTech Connect

This study presnts wireline tool usage in providing proper design parameter values for hydraulic fracture treatments and in evaluating the success of such a treatment. Examples of logging suites are provided and methods are presented for converting log measurements into design values. Techniques are discussed and a matrix chart has been developed for relating tool capabilities with design requirements. It is shown how the formation design parameter values provided by well logging can be used for computer-based numerical simulations aimed at analyzing fracture treatment and post-fracture performance of oil wells. Refs.

Ameri, S.; Rieke, H.H. III

1981-01-01

10

Calculating inverse cv, skew and pwm functions for pearson3, log-normal, extreme-value and log-logistic distributions  

Microsoft Academic Search

Equations are presented to calculate inverse CV, skew and PWM functions for the Pearson-3, log-normal, extreme-value and log-logistic distributions. Such inverse functions are used for moment and PWM estimates. Close numerical approximations are derived for the inverse functions that do not exist explicitly. This is intended to overcome the intractable nature of moment and PWM estimates.

R. W. Donaldson

1996-01-01

11

Load Resistance Value Changes Affect on the Plane Log-periodic Dipole Printed Antenna Characteristics  

Microsoft Academic Search

The paper mainly use Ansoft HFSS electromagnetic field simulation software for the simulation of simple plane log-periodic dipole printed antennas, focused on whether the changes of the far-end loading resistor value impact on such antenna radiation characteristics, using wires patches ~ a feature theoretical calculations of a few approximate phase center equivalent methods. The certification of the accuracy of the

Kong Rong; Su Donglin

2006-01-01

12

INCREASING THE ACCURACY OF COMPUTER CALCULATED LOG P (OCT/WATER) VALUES  

EPA Science Inventory

Like many "expert systems," the CLOGP program incorporates a set of empirically derived rules which are supported by accepted theoretical concepts but which cannot be derived directly from these concepts. igher log P values are expected whenever a larger effective solute cavity i...

13

Deriving TDS values in coarse sediments from long normal and electromagnetic logs.  

PubMed

This paper presents an empirical relationship of quantitatively linked electromagnetic (EM) borehole recordings of the total dissolved solids (TDS) in pore water in the Quaternary deposits of the Belgian coastal plain. First, the long normal (LN) logs are linked to EM logs, then the already developed relationships between LN resistivity measurements and the TDS values are rewritten for EM recordings. The main parameter in these equations is the formation factor, which is derived from ground water analyses and LN logs through Archie's law. The EM recording has several advantages compared to the LN logs. The EM analysis allows measuring in PVC-cased wells and is not hindered by the invasion zone around the well. Furthermore, it has a high vertical resolution. LN logs can be measured only once, after drilling a well; EM recordings can be repeated several times in monitoring wells, which allows the gathering of time-dependent data over a complete vertical cross section. Such data could be obtained with LN logs only in wells with screens over the full-depth interval, which causes a hydraulic short circuit. This short circuit can result in a large artificial flow through the well between different levels, resulting in a salinity profile, which is no longer representative for the studied site. Remediation against short circuiting is a reduction of the screened interval, which strongly reduces the gathered information. The application of the derived equations is one of setting up a monitoring network along the Belgian coast to monitor the trend in salinity levels and comparing present salinity levels with older LN recordings to investigate the salinity changes in the last 30 years. Deep wells already present in the Belgiancoastal plain can then be used to monitor both the fresh water head changes and the salt water evolution. The technique has also been used for parameter identification for which real concentration measurements were needed. PMID:12533073

Van Meir, Nathalie; Lebbe, Luc

14

The weighted log-rank class of permutation tests: P-values and confidence intervals using saddlepoint methods  

Microsoft Academic Search

Test statistics from the weighted log-rank class are commonly used to compare treatment with control when there is right censoring. This paper uses saddlepoint methods to determine mid-p-values from the null permutation distributions of tests from the weighted log-rank class. Analytical saddlepoint computations replace the permutation simulations and provide mid-p-values that are virtually exact for all practical purposes. The speed

Ehab F. Abd-Elfattah; Ronald W. Butler

2007-01-01

15

Technology Transfer via Value-Added Log Processing. Final Report, September 1994-December 1995.  

National Technical Information Service (NTIS)

There are roughly 500,000 electric logs (ES-logs) for wells in the U.S. Many of these are in cased wells, precluding the possibility of further resistivity logging. Software has been developed to predict an earth model directly for the individual curves i...

W. W. Whitman

1995-01-01

16

Unfavorable successional pathways and the conservation value of logged tropical forest  

Microsoft Academic Search

Conservation agencies are increasingly advocating that the survival of many tropical forest species may depend on disturbed forests and are directing scarce conservation resources to managing logged forests. This requires critical evaluation. In this 10-year study, we quantify tree community dynamics in three selectively logged areas harvested at different intensities and compare their recovery to two unlogged areas in Kibale

Colin A. Chapman; Lauren J. Chapman

2004-01-01

17

From Access Points to Materials: A Transaction Log Analysis of Access Point Value for Online Catalog Users.  

ERIC Educational Resources Information Center

|Describes a study that investigated the value of various access points in online catalog records by determining their usefulness to searchers who requested location information for items. Results of a transaction log analysis of the Illinois Library Computer Systems Office online union catalog for 45 academic libraries are discussed. (LRW)|

Wyly, Brendan J.

1996-01-01

18

Global QSAR modeling of logP values of phenethylamines acting as adrenergic alpha-1 receptor agonists.  

PubMed

Global QSAR models predict biological response of molecular structures which are generic in particular class. A global QSAR dataset admits structural features derived from larger chemical space, intricate to model but more applicable in medicinal chemistry. The present work is global in either sense of structural diversity in QSAR dataset or large number of descriptor input. Forty phenethylamine structure derivatives were selected from a large pool (904) of similar phenethylamines available in Pubchem database. LogP values of selected candidates were collected from physical properties database (PHYSPROP) determined in identical set of conditions. Attempts to model logP value have produced significant QSAR models. MLR aided linear one-variable and two-variable QSAR models with their respective R(2) (0.866, 0.937), R(2)A (0.862, 0.932), F-stat (181.936, 199.812) and Standard Error (0.365, 0.255) are statistically fit and found predictive after internal validation and external validation. The descriptors chosen after improvisation and optimization reveal mechanistic part of work in terms of Verhaar model of Fish base-line toxicity from MLOGP, i.e. (BLTF96) and 3D-MoRSE -signal 15 /unweighted molecular descriptor calculated by summing atom weights viewed by a different angular scattering function (Mor15u) are crucial in regulation of logP values of phenethylamines. PMID:23740397

Yadav, Mukesh; Joshi, Shobha; Nayarisseri, Anuraj; Jain, Anuja; Hussain, Aabid; Dubey, Tushar

2013-06-06

19

Deriving Criteria-supporting Benchmark Values from Empirical Response Relationships: Comparison of Statistical Techniques and Effect of Log-transforming the Nutrient Variable  

EPA Science Inventory

In analyses supporting the development of numeric nutrient criteria, multiple statistical techniques can be used to extract critical values from stressor response relationships. However there is little guidance for choosing among techniques, and the extent to which log-transfor...

20

Validation and long-term assessment of an approach for the high throughput determination of lipophilicity (logPOW) values using multiplexed, absorbance-based capillary electrophoresis  

Microsoft Academic Search

A critical evaluation of the use of 96-capillary multiplexed microemulsion electrokinetic chromatography (MMEEKC) for the indirect determination of octanol- water partition coefficients (logPOW values) for a wide range of structurally different compounds is presented. The various components of the microemulsion solution were evaluated and optimized for use in a multiplexed capillary format. A six-component calibration mixture and 23 different solutes

Kit-Sum Wong; Jeremy Kenseth; Roy Strasburg

2004-01-01

21

Improved Ti I log(gf) Values and New Titanium Abundances in the Sun and the Metal-Poor Star HD 84937  

NASA Astrophysics Data System (ADS)

New atomic transition probability measurements for 948 lines of Ti I are reported. Branching fractions from Fourier transform spectra and from spectra recorded using a 3 m echelle spectrometer are combined with published radiative lifetimes from laser induced fluorescence measurements to determine these transition probabilities. Generally good agreement is found in comparisons to the NIST Atomic Spectra Database. These Ti I transition probability data are applied to high-resolution visible and UV spectra of the Sun and the very metal-poor main-sequence turnoff dwarf star HD 84937 to provide new, more accurate values of their titanium abundances. For the solar photosphere we use 168 lines to derive <log ?(Ti)> = 4.97 (? = 0.04), in good agreement with the Ti abundance recommended in previous solar abundance reviews. For HD 84937 we derive <log ?(Ti)> = 3.12 (? = 0.05, 54 lines), or [Ti/H] -1.85. We also determine a new HD 84937 iron metallicity from over 400 Fe I lines in the NIST atomic spectra database, obtaining <log ?(Fe)> = 5.18 (? = 0.08) or [Fe/H] = -2.32. Combining these two results, for HD 84937 we derive [Ti/Fe] = +0.47. This work has been supported by grants NSF AST-0908978 and AST-1211585 (CS), AST-1211055 (JEL), and AST-1004881 (REU at University of Wisconsin).

Sneden, Christopher; Guzman, A.; Lawler, J. E.; Wood, M. P.; Cowan, J. J.

2013-01-01

22

Rare variant collapsing in conjunction with mean log p-value and gradient boosting approaches applied to Genetic Analysis Workshop 17 data  

PubMed Central

In addition to methods that can identify common variants associated with susceptibility to common diseases, there has been increasing interest in approaches that can identify rare genetic variants. We use the simulated data provided to the participants of Genetic Analysis Workshop 17 (GAW17) to identify both rare and common single-nucleotide polymorphisms and pathways associated with disease status. We apply a rare variant collapsing approach and the usual association tests for common variants to identify candidates for further analysis using pathway-based and tree-based ensemble approaches. We use the mean log p-value approach to identify a top set of pathways and compare it to those used in simulation of GAW17 dataset. We conclude that the mean log p-value approach is able to identify those pathways in the top list and also related pathways. We also use the stochastic gradient boosting approach for the selected subset of single-nucleotide polymorphisms. When compared the result of this tree-based method with the list of single-nucleotide polymorphisms used in dataset simulation, in addition to correct SNPs we observe number of false positives.

2011-01-01

23

Transaction Logging.  

ERIC Educational Resources Information Center

|Discusses the use of transaction logging in Okapi-related projects to allow search algorithms and user interfaces to be investigated, evaluated, and compared. A series of examples is presented, illustrating logging software for character-based and graphical user interface systems, and demonstrating the usefulness of relational database management…

Jones, S.; And Others

1997-01-01

24

Transaction Logging.  

ERIC Educational Resources Information Center

Discusses the use of transaction logging in Okapi-related projects to allow search algorithms and user interfaces to be investigated, evaluated, and compared. A series of examples is presented, illustrating logging software for character-based and graphical user interface systems, and demonstrating the usefulness of relational database management…

Jones, S.; And Others

1997-01-01

25

Well logging II - Electric and acoustic logging  

SciTech Connect

This book covers electric logging, log interpretation and electromagnetic principles. The book also discuss principles of acoustic logging and details of acoustic log interpretation, including effects of amplitude attenuation devices and investigation of interval transit times.

Jorden, J.R.; Campbell, F.L.

1986-01-01

26

Improved log(gf) Values Of Selected Lines In Mn I And Mn II For Studies Of Non-equilibrium Effects In Stellar Photospheres  

NASA Astrophysics Data System (ADS)

The work presents transition probabilities with very low uncertainties for a selected set of multiplets of Mn I and Mn II. Multiplets are chosen which are accessible to ground-based observation, are relatively unblended and unsaturated in stellar spectra and which are amenable to accurate branching fraction determination. These lab measurements provide a foundation for studies of non-LTE and 3-dimensional effects in stellar photospheres. We report on new radiative lifetime measurements for 22 levels of Mn I from the e8D, z6P, z6D, z4F, e8S and e6S multiplets and 3 levels of Mn II from the z5P multiplet using time-resolved laser-induced fluorescence on a slow atomic beam. New branching fractions for transitions from these levels, measured using a Fourier-transform spectrometer, are also reported. When combined, these measurements yield transition probabilities for 47 transitions of Mn I and 12 transitions of Mn II. Comparisons are made to data from the literature and to simple Russell-Saunders or LS theory. Final recommended values, which are weighted averages of all available modern measurements and in some cases LS theory, are given for the transition probabilities. These recommended log(gf) values are accurate to +/- 0.02 dex with high ( 2 sigma) confidence. The companion paper applies these new lab results to studies of departures from both LTE in Mn I and Saha equilibrium between Mn I and Mn II on a variety of stellar photospheres. This research is supported in part by NASA Grant NNX08AQ09G and NSF Grant AST-0907732.

Den Hartog, Elizabeth; Lawler, J. E.; Sobeck, J.; Sneden, C.; Cowan, J. J.; Asplund, M.

2010-01-01

27

Micellar electrokinetic chromatography: a new simple tool for the analysis of synthetic cannabinoids in herbal blends and for the rapid estimation of their logP values.  

PubMed

For the first time a capillary separation based on micellar electrokinetic chromatography (MEKC) with diode array detection (DAD) was developed and validated for the rapid determination of synthetic cannabinoids in herbal blends. Separations were carried out on a 30 ?m(ID) × 40 cm uncoated fused silica capillaries. The optimized buffer electrolyte was composed of 25 mM sodium tetraborate pH 8.0, 30 mM SDS and n-propanol 20% (v/v). Separations were performed at 30 kV. Sample injection conditions were 0.5 psi, 10s. Diazepam and JWH-015 were used as internal standards. The determination of the analytes was based on the UV signal recorded at 220 nm, corresponding to the maximum wavelength of absorbance of the molecules, whereas peak identification and purity check were also performed on the basis of the acquisition of UV spectra between 200 and 400 nm wavelengths. Under the described conditions, the separation of the compounds was achieved in 25 min without any significant interference from the matrix. Linearity was assessed within a concentration range from 5 to 100 ?g/mL. The intra-day and inter-day imprecision values were below 2.45% for relative migration times and below 10.75% for relative peak areas. The present method was successfully applied to the direct determination of synthetic cannabinoids in 15 different herbal blend samples requiring only sample dilution. In addition, the developed MEKC separation was also applied to estimate the octanol/water partition coefficients (logP) of these new and poorly known molecules. PMID:23022243

Gottardo, Rossella; Bertaso, Anna; Pascali, Jennifer; Sorio, Daniela; Musile, Giacomo; Trapani, Elisa; Seri, Catia; Serpelloni, Giovanni; Tagliaro, Franco

2012-09-13

28

Log sampling methods and software for stand and landscape ...  

Treesearch

Nov 16, 2010 ... Description: We describe methods for efficient, accurate sampling of logs at ... that have low log abundance compared to values in a land management plan. ... Analysis of log data requires SnagPRO, a user-friendly software ...

29

Logs to Soil  

NSDL National Science Digital Library

In this outdoor activity, learners cut through and investigate rotten logs and then make log-profile puzzles for each other. Learners cut through the limb to expose a vertical profile, study the pattern of decay, and find evidence for the treeâs life history. This activity calls for learners to saw logs, but for younger groups, adults can do the sawing.

Science, Lawrence H.

1982-01-01

30

Well log formation evaluation  

Microsoft Academic Search

A discussion of well logging tools, techniques, and well logging analysis principles is presented. Because no single well logging tool has been developed to measure all the physical properties of rock needed for detailed analysis, tool combinations that will measure porosity, water saturation, hydrocarbons in place, etc. have been developed for various geologic targets. Recently, computers have played an increasingly

Merkel

1979-01-01

31

Log N-log S is inconclusive  

SciTech Connect

The log N-log S data acquired by the Pioneer Venus Orbiter Gamma Burst Detector (PVO) are presented and compared to similar data from the Soviet KONUS experiment. Although the PVO data are consistent with and suggestive of a -3/2 power law distribution, the results are not adequate at this state of observations to differentiate between a -3/2 and a -1 power law slope.

Klebesadel, R.W.; Fenimore, E.E.; Laros, J.

1983-01-01

32

Protect user anonymity in query log  

Microsoft Academic Search

The query logs provide to the research community a large amount of data which reflect the natural behavior of the user on the web. These data have many values and risks on user privacy. The use of these data has prompted several questions: The query logs owners are concerned by the security of their customers. But, academic, governmental and commercial

Anissa Mimi; Safia Nait Bahloul

2010-01-01

33

Low Latency Logging.  

National Technical Information Service (NTIS)

Many database and file systems use a disk log for fast crash recovery. Some of the latency in transaction commit is due to the rotational latency of the disk. The paper shows a design that gives excellent average latency for logging. (Copyright (c) 1991 X...

R. B. Hagmann

1991-01-01

34

6. Log calving barn. Interior view showing log postandbeam support ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. Log calving barn. Interior view showing log post-and-beam support system and animal stalls. - William & Lucina Bowe Ranch, Log Calving Barn, 230 feet south-southwest of House, Melrose, Silver Bow County, MT

35

Transfer Log.xls  

Cancer.gov

ANIMAL TRANSFER LOG Date of Move: ________________ Cage Type C = Auto Water NOTES: B = Water Bottle S = SMZ M = Microisolator ASP # PI GROUP NAME # CAGES [+] ROOM TO DOB COMMENTS STRAIN CODE NEW GROUP NAME NEW ROOM CAGE TYPE PEDIGREE # EAR

36

Influence of chemical characteristics of humic substances on the partition coefficient of a chlorinated dioxin.  

PubMed

The partition coefficients (Koc) of 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (HpCDD) with respect to a variety of humic substances (HSs) were evaluated by a method involving solid-phase microextraction and gas chromatography-electron capture detection. The log Koc values for each of the HS samples were in the range of 6.4-7.7. The log Koc values for HAs from tropical peat, brown forest and ando soils were in the range of 7.3-7.6, similar to the calculated value for the octanol-water partition coefficient (log Koc=7.56). In contrast, the log Koc values for FAs and peat HAs were 0.5-1 unit lower than the calculated value. The parameters for the polarity of HSs, as calculated from (N+O)/C, O/C atomic ratios and the carboxyl group content, were numerically similar related to the log Koc for HpCDD. These results show that the Koc values for HpCDD are significantly influenced by the polarity of HSs. PMID:15686749

Tanaka, Fumiko; Fukushima, Masami; Kikuchi, Atsunori; Yabuta, Hikaru; Ichikawa, Hiroyasu; Tatsumi, Kenji

2005-03-01

37

Modes of log gravity  

SciTech Connect

The physical modes of a recently proposed D-dimensional 'critical gravity', linearized about its anti-de Sitter vacuum, are investigated. All 'log mode' solutions, which we categorize as 'spin-2' or 'Proca', arise as limits of the massive spin-2 modes of the noncritical theory. The linearized Einstein tensor of a spin-2 log mode is itself a 'nongauge' solution of the linearized Einstein equations whereas the linearized Einstein tensor of a Proca mode takes the form of a linearized general coordinate transformation. Our results suggest the existence of a holographically dual logarithmic conformal field theory.

Bergshoeff, Eric A.; Rosseel, Jan [Centre for Theoretical Physics, University of Groningen, Nijenborgh 4, 9747 AG Groningen (Netherlands); Hohm, Olaf [Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Townsend, Paul K. [Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom)

2011-05-15

38

Log of Apollo 11.  

ERIC Educational Resources Information Center

The major events of the first manned moon landing mission, Apollo 11, are presented in chronological order from launch time until arrival of the astronauts aboard the U.S.S. Hornet. The log is descriptive, non-technical, and includes numerous color photographs of the astronauts on the moon. (PR)

National Aeronautics and Space Administration, Washington, DC.

39

Interactive Reflective Logs  

ERIC Educational Resources Information Center

|The authors created an interactive reflective log (IRL) to provide teachers with an opportunity to use a journal approach to record, evaluate, and communicate student understanding of science concepts. Unlike a traditional journal, the IRL incorporates prompts to encourage students to discuss their understanding of science content and science…

Deaton, Cynthia Minchew; Deaton, Benjamin E.; Leland, Katina

2010-01-01

40

Borehole Geophysical Logging  

USGS Multimedia Gallery

USGS hydrologist conducts borehole geophysical logging as part of an applied research project to evaluate the use of new hydrogeophysical tools to remotely monitor and visualize bioremediation of contaminated groundwater. This research is being conducted at the Brandywine Defense Reutilization and M...

2009-03-20

41

Well logging for the nontechnical person  

SciTech Connect

The contents of this book are: Introduction to logging; Reading logs; Formation parameters; Mud logging; Resistivity measurements; Porosity measurements; Putting it all together; detailed interpretations; Computer-generated logs; Specialty logs.

Johnson, D.E.; Pile, K.E.

1988-01-01

42

Newly developed technology for array resistivity logging  

NASA Astrophysics Data System (ADS)

Resistivity logging tools are run in boreholes to locate and quantify the presence of hydrocarbons (oil and gas) in porous rocks. In order to get better reservoir description, three key formation parameters need to be obtained from resistivity logging: (1) formation resistivity Rt; (2) invaded zone resistivity Rxo; (3) invaded length Lxo. None of the conventional resistivity logging tools, normal, lateral, and dual laterolog (DLL), can provide all three parameters with a single run. The newly developed array resistivity logging tool or High-Definition Lateral Log (HDLL, a product developed by Baker Atlas) resistivity tool addresses limitations of existing dual laterolog systems and provides all three parameters with a single run. The key developments in this dissertation are: (1) deep (up to 50 inches from borehole wall) Synthetic Focused Resistivity (SFR) logs from HDLL measurements; (2) shallow (close to 10 inches from borehole wall) SFR logs from HDLL measurements; (3) robust computation of SFR via array processing; (4) inverse vertical resolution matching (IRM) method for SFR; (5) inversion of HDLL array data in both vertical and highly deviated wells. The wellsite interpretation for array resistivity logging is developed by synthesizing focused resistivity logs from the raw HDLL data. The developed SFRs provide a better resolution of the resistivity distribution in both vertical and radial directions than DLL logs. The array processing method is developed to detect and correct errors in the raw measurements, and to evaluate the quality of the data. With the newly developed inverse vertical resolution matching method, we succeed in the resolution matching for the HDLL SFR logs. The HDLL inversion process developed in this study has three major steps: (1) estimating shallow resistivity structure; (2) estimating deep resistivity structure; and, (3) combining the results of the previous steps to produce the entire true resistivity structure. The results in a final model have a constant Rxo, Lxo, and Rt values in each layer. In the presented cases, HDLL-based interpretations show not only improved delineation of the known reservoirs but also extra pay intervals overlooked by DLL-based interpretations.

Zhou, Zhiqiang

43

Review of Log Sort Yards.  

National Technical Information Service (NTIS)

This report provides a general overview of current log sort yard operations in the United States, including an extensive literature review and information collected during on-site visits to several operations throughout the nation. Log sort yards provide ...

J. R. Dramm G. L. Jackson J. Wong

2002-01-01

44

Analysis of open hole logs in the Miocene Stevens Sands  

SciTech Connect

The analysis of open-hole logs in the Stevens Sands is difficult because of the mineralogical composition of the sands and the corresponding effects on the logging tools. Logging parameters presumed in other sandstone reservoirs may not be appropriate to the Stevens and may cause the log analysis to underestimate productive zones. Without the integration of full core data and knowledge of the mineralogy of the Stevens Sands, the results of log analysis can be very misleading. As shown in the example used in this paper, the net pay footage calculated using conventional cutoffs can be improved from 10 to 45 ft by using the core measured rather than the commonly assumed valued for logging parameters. The increased pay footage is achieved by changing the mean water saturation from 70%, calculated using commonly assumed parameters, to a mean value of 48% calculated using core measured parameters.

Morrow, J.

1991-02-01

45

FCC Logging and Operator Rules  

Microsoft Academic Search

The Federal Communications Commission has adopted new rules concerning the qualifications of operators of broadcast stations. The transmitting equipment of each station will be subject to periodic inspections and a maintenance log pertaining thereto will be kept. Clarifications are listed concerning present entries in the operating log of a station. In case the station contemplates the use of automatic logging

Harold Kassens

1964-01-01

46

Grid Logging: Best Practices Guide  

SciTech Connect

The purpose of this document is to help developers of Grid middleware and application software generate log files that will be useful to Grid administrators, users, developers and Grid middleware itself. Currently, most of the currently generated log files are only useful to the author of the program. Good logging practices are instrumental to performance analysis, problem diagnosis, and security auditing tasks such as incident tracing and damage assessment. This document does not discuss the issue of a logging API. It is assumed that a standard log API such as syslog (C), log4j (Java), or logger (Python) is being used. Other custom logging API or even printf could be used. The key point is that the logs must contain the required information in the required format. At a high level of abstraction, the best practices for Grid logging are: (1) Consistently structured, typed, log events; (2) A standard high-resolution timestamp; (3) Use of logging levels and categories to separate logs by detail and purpose; (4) Consistent use of global and local identifiers; and (5) Use of some regular, newline-delimited ASCII text format. The rest of this document describes each of these recommendations in detail.

Tierney, Brian L; Tierney, Brian L; Gunter, Dan

2008-04-01

47

Log evaluation of oil-bearing igneous rocks  

SciTech Connect

The evaluation of porosity, water saturation and clay content of oilbearing igneous rocks with well logs is difficult due to the mineralogical complexity of this type of rocks. The log responses to rhyolite and rhyolite tuff; andesite, dacite and zeolite tuff; diabase and basalt have been studied from examples in western Argentina and compared with values observed in other countries. Several field examples show how these log responses can be used in a complex lithology program to make a complete evaluation.

Khatchikian, A.

1983-12-01

48

The Lincoln Log  

NSDL National Science Digital Library

What exactly was Abraham Lincoln doing on June 11, 1850? As it turns out, he was writing a letter to one Nathaniel Hay, describing the details of a potential home-improvement project. If you're looking for more details on Lincoln's daily doings, click on over to The Lincoln Log. The information on the site was compiled by the Lincoln Sesquicentennial Commission, and in 2003, the materials were redesigned by the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign. Visitors to the site can find out what Lincoln was doing on a particular day by using the drop-down menus on the homepage, and they can also browse by year or click on the "Today's Date in Lincoln's Life" section. Also, visitors can use the "Browse New Entries" to look over newly added materials.

49

Research on Privacy Preserving Data in Web Log Mining  

Microsoft Academic Search

Researches on preserving private data in the application of web data mining possess practical value. Through introducing basic concepts of web log mining and private data protection, this paper analyzes the status quo of privacy preservation in web log mining, and then it puts forward privacy preserving mining model based on evolutionary algorithm of cloud model, combining with evolutionary algorithm

Chang-bin Jiang; Li Chen

2010-01-01

50

Applying the log-normal distribution to target detection  

NASA Astrophysics Data System (ADS)

Holst and Pickard experimentally determined that MRT responses tend to follow a log-normal distribution. The log normal distribution appeared reasonable because nearly all visual psychological data is plotted on a logarithmic scale. It has the additional advantage that it is bounded to positive values; an important consideration since probability of detection is often plotted in linear coordinates. Review of published data suggests that the log-normal distribution may have universal applicability. Specifically, the log-normal distribution obtained from MRT tests appears to fit the target transfer function and the probability of detection of rectangular targets.

Holst, Gerald C.

1992-09-01

51

Logging for carbon tetrachloride contamination  

SciTech Connect

Neutron activation logging systems were used to prospect for residual saturations of carbon tetrachloride contamination at a nuclear weapons production facility. Logging was performed in wells near a former disposal trench, where up to 30,000 l were discharged between 1955 and 1962. The majority of this contamination has not been accounted for. To test for the presence of chlorine, a geochemical logging system was use to record capture gamma-ray spectra.

Grau, J.A.; Ellis, D.V. [Schlumberger-Doll, Ridgefield, CT (United States); Lewis, R.E. [Battelle-Pacific Northwest Lab., Richland, WA (United States)] [and others

1995-12-31

52

Log-domain wave filters  

Microsoft Academic Search

A systematic method for designing log-domain wave filters is presented. Wave filters simulate topologically and functionally passive doubly terminated LC ladder prototype filters of low sensitivity. The design in the log-domain is based on a transposition of the signal flow graph (SFG) that corresponds to the wave equivalent of elementary two-port blocks in the linear domain, to the corresponding log-domain

C. Psychalinos; N. Fragoulis; I. Haritantis

2004-01-01

53

Acoustic paramagnetic logging tool  

SciTech Connect

New methods and apparatus are disclosed which allow measurement of the presence of oil and water in geological formations using a new physical effect called the Acoustic Paramagnetic Logging Effect (APLE). The presence of petroleum in formation causes a slight increase in the earth's magnetic field in the vicinity of the reservoir. This is the phenomena of paramagnetism. Application of an acoustic source to a geological formation at the Larmor frequency of the nucleons present causes the paramagnetism of the formation to disappear. This results in a decrease in the earth3 s magnetic field in the vicinity of the oil bearing formation. Repetitively frequency sweeping the acoustic source through the Larmor frequency of the nucleons present (approx. 2 kHz) causes an amplitude modulation of the earth's magnetic field which is a consequence of the APLE. The amplitude modulation of the earth's magnetic field is measured with an induction coil gradiometer and provides a direct measure of the amount of oil and water in the excitation zone of the formation . The phase of the signal is used to infer the longitudinal relaxation times of the fluids present, which results in the ability in general to separate oil and water and to measure the viscosity of the oil present. Such measurements may be preformed in open boreholes and in cased well bores.

Vail, III, William B. (Bothell, WA)

1988-01-01

54

Well Logging and Logging Analysis of UHP metamorphic Rocks in CCSD Main Hole (0-2000m)  

NASA Astrophysics Data System (ADS)

CCSD logging engineering gather many modern high technologies and employs various advanced logging tools to survey the sidewall continuously. This can obtain various physical, chemical, geometrical, etc in-situ information of the borehole's profile. So well logging is one of the most important parts and pivotal technologies in the project of CCSD. The main logging methods in CCSD-MH(0-2000m) are laterolog (Rd,Rs), gamma ray(GR), nature gamma spectrometry(U, TH, K), density(DEN), photo electric section exponent (Pe), compensated neutron(CNL), multipole array acoustic (Vp, Vs, Vst), Simultaneous Acoustic-Resistivity-image(Star-II), temperature(T),magnetic susceptibility(MS), three component borehole magnetic and redox potential log,etc. The various metamorphic rocks can be classified by logging curves,and their physical parameters can be acquired by analyzing the response characters of various metamorphic rocks and by statistics. According to the logging cross plot, We can research the clustering of metamorphite's physical property. Five lithologic segments can be obtainend by logging curves. The GR, Th, U, K logging values of segment 1 is lower than the third, fourth and fiveth segment, higher than segment 2; The DEN, Pe values of segment 1 higher than the third, fourth and fiveth segments. The main rocks in segment 1,2,3,4,5 are eclogites, serpentinites, paragneiss, orthogneiss, and eclogites(containing silicon and muscovite ) respectively. Generally, eclogite contain rutile, silicon, muscovite, etc. minerals. These minerals have response obviously on log curves.There are rutile,ilmenite, pyrite mineralized, etc. Making use of DEN, Pe, susceptibility log values, these mineralized layers can be goodly demarcation. For example, on the rutile mineralzed layer, the logging curve response characters are of high density and Pe obviously. The key data of the synthetical seismic record is wave impedance. In this paper, Utilize the data of AC, DEN curves to calculate the wave impedance and compare with the VSP profile, finally analyze the reflectors of the CCSD-MH. Imaging log has a positioning system and very good vertical resolution, and can describe the geological features in detail. Various structure parameters (the size and occurrences of foliation, fracture, fault & vein) have been given by image logging. The main work of logging interpretation of CCSD have done as follows: 1) Character analysis of logging response and restoring the lithologic profile;2) Depth correction and Restoring orientation of cores; 3) Interpretation of imaging geological feature; 4) Research of rock's mechanics character, sonic anisotropy and formation stress; 5) Comparison wave impedance with the VSP profile,analyzing the reflectors; 6)The interpretation of magnetic susceptibility and temperature log. The logging analysis results of UHP metamorphic rocks in CCSD-MH(0-2000m) show that responses of logs curve are abundant, the physical properties of various metamorphic rocks are visibly different;image logging has a positioning system and very good vertical resolution, and can describe the geological features in detail;lithologic segments and mineralized layers can be goodly demarcation by log curves;the log curves can be used for standardizing the geophysical survey, for example, mark out the reflected interface of seismic wave;comparing the results of log curves value with core laboratory analysis,they have good consistency;and so on.

Pan, H.; Niu, Y.; Wang, W.; Zhu, L.; Xu, D.; Wu, H.; Li, S.; Luo, M.

2004-12-01

55

Malware, Viruses and Log Visualisation  

Microsoft Academic Search

This paper will look at the current state of visualization in relation to mainly malware collector logs, network logs and the possibility of visualizing their payloads. We will show that this type of visualization of activity on the network can help us in the forensic investigation of the traffic, which may contain unwanted pieces of cod, and may identify any

Iain Swanson

2008-01-01

56

Sonic log prediction in carbonates  

NASA Astrophysics Data System (ADS)

This work is conducted to study the complications associated with the sonic log prediction in carbonate logs and to investigate the possible solutions to accurately predict the sonic logs in Traverse Limestone. Well logs from fifty different wells were analyzed to define the mineralogy of the Traverse Limestone by using conventional 4-mineral and 3-mineral identification approaches. We modified the conventional 3-mineral identification approach (that completely neglects the gamma ray response) to correct the shale effects on the basis of gamma ray log before employing the 3-mineral identification. This modification helped to get the meaningful insight of the data when a plot was made between DGA (dry grain density) and UMA (Photoelectric Volumetric Cross-section) with the characteristic ternary diagram of the quartz, calcite and dolomite. The results were then compared with the 4-mineral identification approach. Contour maps of the average mineral fractions present in the Traverse Limestone were prepared to see the basin wide mineralogy of Traverse Limestone. In the second part, sonic response of Traverse Limestone was predicted in fifty randomly distributed wells. We used the modified time average equation that accounts for the shale effects on the basis of gamma ray log, and used it to predict the sonic behavior from density porosity and average porosity. To account for the secondary porosity of dolomite, we subtracted the dolomitic fraction of clean porosity from the total porosity. The pseudo-sonic logs were then compared with the measured sonic logs on the root mean square (RMS) basis. Addition of dolomite correction in modified time average equation improved the results of sonic prediction from neutron porosity and average porosity. The results demonstrated that sonic logs could be predicted in carbonate rocks with a root mean square error of about 4isec/ft. We also attempted the use of individual mineral components for sonic log prediction but the ambiguities in mineral fractions and in the sonic properties of the minerals limited the accuracy of the results.

Islam, Nayyer

57

A new approach for deriving pseudovelocity logs from resistivity logs  

SciTech Connect

This paper describes a method of generating pseudovelocity logs using measurements of electrical resistivity. A theoretical relation between electrical resistivity and transit time, which is applicable to a wide range of lithologies, has been developed. The application of this relation using a method which defines lithoresistivity zones as lithological intervals related to the same formation and showing small resistivity variations, has been tested in the Reconcavo sedimentary basin in Bahia, Brazil. A comparison of derived pseudovelocity logs with actual sonic logs for five wells shows the validity of the present approach.

Dos Santos, W.L.B.; Ulrych, T.J.; De Lima, O.A.L.

1988-01-01

58

Improved grading system for structural logs for log homes  

Treesearch

... diameter than would be required if a more precise grading method were available. ... The logs were tested in bending and in compression parallel to grain . ... to be the best single predictor of static strength and modulus of elasticity (MOE ).

59

A regularity-based modeling of oil borehole logs  

NASA Astrophysics Data System (ADS)

Multifractional Brownian motions (mBms) are successfully used to describe borehole logs behavior. These local fractal models allow to investigate the depth-evolution of regularity of the logs, quantified by the Hölder exponent (H). In this study, a regularity analysis is carried out on datasets recorded in Algerian oil boreholes located in different geological settings. The obtained regularity profiles show a clear correlation with lithology. Each lithological discontinuity corresponds to a jump in H value. Moreover, for a given borehole, all the regularity logs are significantly correlated and lead to similar lithological segmentations. Therefore, the Hölderian regularity is a robust property which can be used to characterize lithological heterogeneities. However, this study does not draw any relation between the recorded physical property and its estimated regularity degree for all the analyzed logs. Keywords: well logs, regularity, Hölder exponent, multifractional Brownian motion

Gaci, Said; Zaourar, Naima

2013-04-01

60

Well logging data transmission system  

SciTech Connect

A telemetering system provides improved cable utilization and bi-directional digital communication between a logging sonde and surface electronics over a single balanced transmission line of a multi-conductor logging cable, with significant signal crosstalk reductions. Receiver circuitry downhole decodes pulses delivered on the line from a surface logic generator which fire transmitter-receiver pairs of an acoustic logging tool in an order defined by the pulses. A PCM transmitter in the sonde thereafter samples data generated by other logging instruments, encodes this information into digital data frames, and transmits the data on the same line to a surface PCM receiver. Circuitry limits surface and downhole receiver response to PCM transmitter and logic generator pulses, respectively. A center tap of the same transmission line also provides for simultaneous noise-free transmission of sensitive low level signals such as remote surface potential and the like to the sonde.

Flagg, J.J.

1983-11-15

61

Animal Room Log.xls  

Cancer.gov

ANIMAL ROOM LOG Room Number: __________ Cage Type Death Cause C = Auto Water EU = Euthanized NOTES: B = Water Bottle FD = Found Dead S = SMZ DR = Drowned M = Microisolator MI = Missing TO = Transfer Out DEATH CAUSE STRAIN CODE GROUP NAME # ? # ? COMMENTS

62

Lacunarity of geophysical well logs in the Cantarell oil field, Gulf of Mexico  

Microsoft Academic Search

Lacunarity and fractal variations in geophysical well logs are associated with stratigraphic and petrophysical properties of the naturally fractured Cantarell field in the Gulf of Mexico. Neutron porosity (NPHI), density (RHOB, DRHO, PEF), resistivity (LLD, LLS, MSFL), natural radioactivity (GR, CGR, URAN, POTA, THOR) and caliper (CALI) logs are studied. The resistivity logs yielded remarkably high lacunarity values, especially in

Rubén Darío Arizabalo; Klavdia Oleschko; Gabor Korvin; Manuel Lozada; Ricardo Castrejón; Gerardo Ronquillo

2006-01-01

63

Numerical simulation of responses for cased-hole density logging  

NASA Astrophysics Data System (ADS)

Stabilizing or stimulating oil production in old oil fields requires density logging in cased holes where open-hole logging data are either missing or of bad quality. However, measured values from cased-hole density logging are more severely influenced by factors such as fluid, casing, cement sheath and the outer diameter of the open-hole well compared with those from open-hole logging. To correctly apply the cased-hole formation density logging data, one must eliminate these influences on the measured values and study the characteristics of how the cased-hole density logging instrument responds to these factors. In this paper, a Monte Carlo numerical simulation technique was used to calculate the responses of the far detector of a cased-hole density logging instrument to in-hole fluid, casing wall thickness, cement sheath density and the formation and thus to obtain influence rules and response coefficients. The obtained response of the detector is a function of in-hole liquid, casing wall thickness, the casing's outer diameter, cement sheath density, open-hole well diameter and formation density. The ratio of the counting rate of the detector in the calibration well to that in the measurement well was used to get a fairly simple detector response equation and the coefficients in the equation are easy to acquire. These provide a new way of calculating cased-hole density through forward modelling methods.

Wu, Wensheng; Fu, Yaping; Niu, Wei

2013-10-01

64

Evaluation of waste mushroom logs as a potential biomass resource for the production of bioethanol  

Microsoft Academic Search

In order to investigate the possibility of using waste mushroom logs as a biomass resource for alternative energy production, the chemical and physical characteristics of normal wood and waste mushroom logs were examined. Size reduction of normal wood (145kWh\\/tone) required significantly higher energy consumption than waste mushroom logs (70kWh\\/tone). The crystallinity value of waste mushroom logs was dramatically lower (33%)

Jae-Won Lee; Bon-Wook Koo; Joon-Weon Choi; Don-Ha Choi; In-Gyu Choi

2008-01-01

65

47 CFR 87.109 - Station logs.  

Code of Federal Regulations, 2011 CFR

...Procedures Operating Procedures § 87.109 Station logs. (a) A station at a fixed location in the international aeronautical mobile service must maintain a log in accordance with Annex 10 of the ICAO Convention. (b) A station log must...

2011-10-01

66

DOE/Simplec Magnetic Susceptibility Logging System.  

National Technical Information Service (NTIS)

A magnetic susceptibility logging system has been developed which is relatively stable under normal field logging conditions and which produces logs that accurately represent in situ variations in magnetic susceptibility. However, both field and laborator...

D. A. Emilia J. W. Allen R. B. Chessmore R. B. Wilson

1981-01-01

67

Degraded lands worth protecting: the biological importance of Southeast Asia's repeatedly logged forests.  

PubMed

Southeast Asia is a hotspot of imperiled biodiversity, owing to extensive logging and forest conversion to oil palm agriculture. The degraded forests that remain after multiple rounds of intensive logging are often assumed to be of little conservation value; consequently, there has been no concerted effort to prevent them from being converted to oil palm. However, no study has quantified the biodiversity of repeatedly logged forests. We compare the species richness and composition of birds and dung beetles within unlogged (primary), once-logged and twice-logged forests in Sabah, Borneo. Logging had little effect on the overall richness of birds. Dung beetle richness declined following once-logging but did not decline further after twice-logging. The species composition of bird and dung beetle communities was altered, particularly after the second logging rotation, but globally imperiled bird species (IUCN Red List) did not decline further after twice-logging. Remarkably, over 75 per cent of bird and dung beetle species found in unlogged forest persisted within twice-logged forest. Although twice-logged forests have less biological value than primary and once-logged forests, they clearly provide important habitat for numerous bird and dung beetle species. Preventing these degraded forests from being converted to oil palm should be a priority of policy-makers and conservationists. PMID:20685713

Edwards, David P; Larsen, Trond H; Docherty, Teegan D S; Ansell, Felicity A; Hsu, Wayne W; Derhé, Mia A; Hamer, Keith C; Wilcove, David S

2010-08-04

68

Degraded lands worth protecting: the biological importance of Southeast Asia's repeatedly logged forests  

PubMed Central

Southeast Asia is a hotspot of imperilled biodiversity, owing to extensive logging and forest conversion to oil palm agriculture. The degraded forests that remain after multiple rounds of intensive logging are often assumed to be of little conservation value; consequently, there has been no concerted effort to prevent them from being converted to oil palm. However, no study has quantified the biodiversity of repeatedly logged forests. We compare the species richness and composition of birds and dung beetles within unlogged (primary), once-logged and twice-logged forests in Sabah, Borneo. Logging had little effect on the overall richness of birds. Dung beetle richness declined following once-logging but did not decline further after twice-logging. The species composition of bird and dung beetle communities was altered, particularly after the second logging rotation, but globally imperilled bird species (IUCN Red List) did not decline further after twice-logging. Remarkably, over 75 per cent of bird and dung beetle species found in unlogged forest persisted within twice-logged forest. Although twice-logged forests have less biological value than primary and once-logged forests, they clearly provide important habitat for numerous bird and dung beetle species. Preventing these degraded forests from being converted to oil palm should be a priority of policy-makers and conservationists.

Edwards, David P.; Larsen, Trond H.; Docherty, Teegan D. S.; Ansell, Felicity A.; Hsu, Wayne W.; Derhe, Mia A.; Hamer, Keith C.; Wilcove, David S.

2011-01-01

69

APS logDaemon and client library  

SciTech Connect

This document serves as a User`s Manual and Reference for the logDaemon and client library. This package provides a general distributed message logging system. A logDaemon may be started anywhere on a subnet. A client which has linked in the client library is provided functions to open a connection to the logDaemon, log messages, and close the connection. The logDaemon maintains one or more log files (in simple ASCII or SDDS format) and an e-mail list based on specifications in a configuration file. Incoming messages are logged to the appropriate file and/or result in e-mail being sent.

Saunders, C.; Kowalkowski, J.

1995-12-13

70

Logging damage during planned and unplanned logging operations in the eastern Amazon  

Microsoft Academic Search

In the Paragominas region of eastern Amazonia, we compared the damage in unplanned and planned logging operations associated with each of five logging phases: (1) tree felling, (2) machine maneuvering to attach felled boles to chokers, (3) skidding boles to log landings, (4) constructing log landings and (5) constructing logging roads. Planned logging was conducted with a rubber-wheeled skidder or

Jennifer S. Johns; Paulo Barreto; Christopher Uhl

1996-01-01

71

Quantitative Literacy: Working with Log Graphs  

NASA Astrophysics Data System (ADS)

The need for working with and understanding different types of graphs is a common occurrence in everyday life. Examples include anything having to do investments, being an educated juror in a case that involves evidence presented graphically, and understanding many aspect of our current political discourse. Within a science class graphs play a crucial role in presenting and interpreting data. In astronomy, where the range of graphed values is many orders of magnitude, log-axes must be used and understood. Experience shows that students do not understand how to read and interpret log-axes or how they differ from linear. Alters (1996), in a study of college students in an algebra-based physics class, found little understanding of log plotting. The purpose of this poster is to show the method and progression I have developed for use in my “ASTRO 101” class, with the goal being to help students better understand the H-R diagram, mass-luminosity relationship, and digital spectra.

Shawl, S.

2013-04-01

72

Well-logging activities in Russia  

SciTech Connect

The report is a brief survey of the current state of well-logging service in Russia (number and types of crews, structure of well-logging jobs, types of techniques used, well-logging equipment, auxiliary downhole jobs, etc.). Types and peculiarities of well data acquisition and processing hardware and software are discussed (petrophysics included). New well-logging technologies used in Russia (new methods of electric logging data processing, electromagnetic logging, pulse neutron logging, nuclear magnetic resonance logging, acoustic tomography, logging-testing-logging technique, etc.) are surveyed. Comparison of the Tengiz field (Kazakhstan) well data obtained by Schlumberger and Neftegazgeofizika Association crews is given. Several problems and drawbacks in equipment and technology used by well-logging crews in Russia are discussed.

Savostyanov, N.A. (Neftegazgeofizika, Moscow (Russian Federation))

1993-09-01

73

Determination of the distribution coefficient (log K d) of oxytetracycline, tylosin A, olaquindox and metronidazole in manure  

Microsoft Academic Search

Olaquindox (logKow=?2.3) and metronidazole (logKow=?0.1) both have low tendencies to sorp to particles in manure. This corresponds with the negative logKow values of these antibiotics. Tylosin (logKow=1.63) and oxytetracycline (logKow=?1.12) sorp relatively strongly to the manure particles and have logKd values between 1.5 and 2.0. The tendency to bind to manure was ranked after increasing binding as follows: metronidazole

Marie-Louise Loke; Jette Tjørnelund; Bent Halling-Sørensen

2002-01-01

74

A New Approach to Logging.  

ERIC Educational Resources Information Center

In response to high numbers of preventable fatal accidents in the logging industry, the Occupational Safety and Health Administration (OSHA) developed a week-long logger safety training program that includes hands-on learning of safety techniques in the woods. Reaching small operators has been challenging; outreach initiatives in Maine, North…

Miles, Donna

2001-01-01

75

Continuous shear wave logging apparatus  

SciTech Connect

Apparatus for continuous shear wave logging of a borehole consisting of a sonde instrument having retractable, expandable coupling arms for rigidly engaging the borehole wall to exert repetitive torqueing action while continuously moving uphole. The sonde includes spaced detector coupling arms in continual contact with the borehole wall and polarized for detection of the repetitive propagated shear waves.

Brown, G. L.

1985-10-29

76

Outdoor Education Student Log Book.  

ERIC Educational Resources Information Center

|A student log book for outdoor education was developed to aid Oakland County (Michigan) teachers and supervisors of outdoor education in preparing student campers for their role and responsibilities in the total program. A sample letter to sixth graders explains the purpose of the booklet. General camp rules (10) are presented, followed by 6…

Garbutt, Barbara; And Others.

77

Downhole Memory-Logging Tools  

SciTech Connect

Logging technologies developed for hydrocarbon resource evaluation have not migrated into geothermal applications even though data so obtained would strengthen reservoir characterization efforts. Two causative issues have impeded progress: (1) there is a general lack of vetted, high-temperature instrumentation, and (2) the interpretation of log data generated in a geothermal formation is in its infancy. Memory-logging tools provide a path around the first obstacle by providing quality data at a low cost. These tools feature onboard computers that process and store data, and newer systems may be programmed to make ''decisions''. Since memory tools are completely self-contained, they are readily deployed using the slick line found on most drilling locations. They have proven to be rugged, and a minimum training program is required for operator personnel. Present tools measure properties such as temperature and pressure, and the development of noise, deviation, and fluid conductivity logs based on existing hardware is relatively easy. A more complex geochemical tool aimed at a quantitative analysis of potassium, uranium and thorium will be available in about one year, and it is expandable into all nuclear measurements common in the hydrocarbon industry. A second tool designed to sample fluids at conditions exceeding 400 C (752 F) is in the proposal stage. Partnerships are being formed between the geothermal industry, scientific drilling programs, and the national laboratories to define and develop inversion algorithms relating raw tool data to more pertinent information.

Lysne, Peter

1992-03-24

78

Stable pairs and log flips  

Microsoft Academic Search

This paper has two parts. In the first part, we review stable pairs and triples on curves, leading up to Thaddeus' diagram of flips and contractions starting from the blow-up of projective space along a curve embedded by a complete linear series of the form K + ample. In the second part, we identify log canonical divisors which exhibit Thaddeus'

Aaron Bertram

1997-01-01

79

A New Approach to Logging.  

ERIC Educational Resources Information Center

|In response to high numbers of preventable fatal accidents in the logging industry, the Occupational Safety and Health Administration (OSHA) developed a week-long logger safety training program that includes hands-on learning of safety techniques in the woods. Reaching small operators has been challenging; outreach initiatives in Maine, North…

Miles, Donna

2001-01-01

80

Improving Voting System Event Logs  

Microsoft Academic Search

Federal standards require that electronic voting machines log information about the voting system behavior to support post-election audits and investigations. Our study examines what additional voter interaction information should be collected to allow investigation of human factors issues of the voting systems used in an election, while at the same time preserving voter privacy. We have focused on simulating touch

Andrea L. Mascher; Paul T. Cotton; Douglas W. Jones

2009-01-01

81

Statistical log analysis made practical  

SciTech Connect

This paper discusses the advantages of a statistical approach to log analysis. Statistical techniques use inverse methods to calculate formation parameters. The use of statistical techniques has been limited, however, by the complexity of the mathematics and lengthy computer time required to minimize traditionally used nonlinear equations.

Mitchell, W.K.; Nelson, R.J. (Oryx Energy Co., Dallas, TX (US))

1991-06-01

82

An innovative OSCE clinical log station: a quantitative study of its influence on Log use by medical students  

PubMed Central

Background A Clinical Log was introduced as part of a medical student learning portfolio, aiming to develop a habit of critical reflection while learning was taking place, and provide feedback to students and the institution on learning progress. It was designed as a longitudinal self-directed structured record of student learning events, with reflection on these for personal and professional development, and actions planned or taken for learning. As incentive was needed to encourage student engagement, an innovative Clinical Log station was introduced in the OSCE, an assessment format with established acceptance at the School. This study questions: How does an OSCE Clinical Log station influence Log use by students? Methods The Log station was introduced into the formative, and subsequent summative, OSCEs with careful attention to student and assessor training, marking rubrics and the standard setting procedure. The scoring process sought evidence of educational use of the log, and an ability to present and reflect on key learning issues in a concise and coherent manner. Results Analysis of the first cohort’s Log use over the four-year course (quantified as number of patient visits entered by all students) revealed limited initial use. Usage was stimulated after introduction of the Log station early in third year, with some improvement during the subsequent year-long integrated community-based clerkship. Student reflection, quantified by the mean number of characters in the ‘reflection’ fields per entry, peaked just prior to the final OSCE (mid-Year 4). Following this, very few students continued to enter and reflect on clinical experience using the Log. Conclusion While the current study suggested that we can’t assume students will self-reflect unless such an activity is included in an assessment, ongoing work has focused on building learner and faculty confidence in the value of self-reflection as part of being a competent physician.

2012-01-01

83

Geomicrobial Optical Logging Detectors (GOLD)  

Microsoft Academic Search

We will present concepts for downhole instrumentation that could be used in the Deep Underground Science and Engineering Laboratory (DUSEL). We envision optical borehole-logging instruments that could monitor bacterial concentration, mineralogy, aromatic organics, temperature and oxygen concentration, allowing for the in situ monitoring of time-dependent microbial and short-scale geologic processes and provide valuable in situ data on stratigraphy to supplement

N. E. Bramall; C. R. Stoker; P. B. Price; J. D. Coates; L. J. Allamandola; A. L. Mattioda

2008-01-01

84

Keep a "SLOG" (Sleep Log)  

NSDL National Science Digital Library

In this activity (1st on the page), learners keep a "SLOG" or Sleep Log to study their sleep patterns. Learners keep track of their sleep behavior and the dreams that they have each night on the "Dream Journal Worksheet" and "Sleep Journal Worksheet" included in this activity guide. This guide also includes twenty questions for learners to consider when recording and analyzing their dreams.

Chudler, Eric H.

2009-01-01

85

Chemical logging of geothermal wells  

DOEpatents

The presence of geothermal aquifers can be detected while drilling in geothermal formations by maintaining a chemical log of the ratio of the concentrations of calcium to carbonate and bicarbonate ions in the return drilling fluid. A continuous increase in the ratio of the concentrations of calcium to carbonate and bicarbonate ions is indicative of the existence of a warm or hot geothermal aquifer at some increased depth.

Allen, Charles A. (Idaho Falls, ID); McAtee, Richard E. (Idaho Falls, ID)

1981-01-01

86

Log-periodic crashes revisited  

NASA Astrophysics Data System (ADS)

We revisit the finding that crashes can be deterministic and governed by log-periodic formulas [D. Sornette, A. Johansen, Significance of log-periodic precursors to financial crashes, Quant. Finance 1 (2001) 452 471; D. Sornette, W.X. Zhou, The US 2000 2002 market descent: how much longer and deeper?, Quant. Finance 2 (2002) 468 481]. One- and two-harmonic equations are usually employed to fit daily data during bubble episodes. But a three-harmonics has been shown to fit anti-bubbles [A. Johansen, D. Sornette, Financial “anti-bubbles”: log-periodicity in gold and Nikkei collapses, Int. J. Mod. Phys. C 10 (1999) 563 575]. Here we show that the three-harmonic formula can work for bubble episodes as well as anti-bubbles. This is illustrated with daily data from the Brazilian real-US dollar exchange rate. And we also show that the three-harmonics can fit an intraday data set from that foreign exchange rate.

Matsushita, Raul; da Silva, Sergio; Figueiredo, Annibal; Gleria, Iram

2006-05-01

87

29 CFR 42.7 - Complaint/directed action logs.  

Code of Federal Regulations, 2010 CFR

...Complaint/directed action logs. 42.7 Section 42.7...Complaint/directed action logs. (a) To facilitate...oversee the operation of a system of coordinated Complaint/Directed Action Logs (logs ). The logs...

2009-07-01

88

29 CFR 42.7 - Complaint/directed action logs.  

Code of Federal Regulations, 2010 CFR

...Complaint/directed action logs. 42.7 Section 42.7...Complaint/directed action logs. (a) To facilitate...oversee the operation of a system of coordinated Complaint/Directed Action Logs (logs ). The logs...

2010-07-01

89

Log-Euclidean free-form deformation  

NASA Astrophysics Data System (ADS)

The Free-Form Deformation (FFD) algorithm is a widely used method for non-rigid registration. Modifications have previously been proposed to ensure topology preservation and invertibility within this framework. However, in practice, none of these yield the inverse transformation itself, and one loses the parsimonious B-spline parametrisation. We present a novel log-Euclidean FFD approach in which a spline model of a stationary velocity field is exponentiated to yield a diffeomorphism, using an efficient scaling-and-squaring algorithm. The log-Euclidean framework allows easy computation of a consistent inverse transformation, and offers advantages in group-wise atlas building and statistical analysis. We optimise the Normalised Mutual Information plus a regularisation term based on the Jacobian determinant of the transformation, and we present a novel analytical gradient of the latter. The proposed method has been assessed against a fast FFD implementation (F3D) using simulated T1- and T2-weighted magnetic resonance brain images. The overlap measures between propagated grey matter tissue probability maps used in the simulations show similar results for both approaches; however, our new method obtains more reasonable Jacobian values, and yields inverse transformations.

Modat, Marc; Ridgway, Gerard R.; Daga, Pankaj; Cardoso, M. J.; Hawkes, David J.; Ashburner, John; Ourselin, Sébastien

2011-03-01

90

Geophysical Logging of the Harwell Boreholes.  

National Technical Information Service (NTIS)

A comprehensive geophysical borehole logging survey was carried out on each of three deep boreholes drilled at the Harwell research site. KOALA and PETRA computer programs were used to analyse and interpret the logs to obtain continuous quantitative estim...

M. A. Brightman

1983-01-01

91

Data transmission system for downhole logging tools  

SciTech Connect

This patent describes a data transmission system for use with a multiple conductor logging cable on a cable reel connecting a downhole tool to a logging truck. It comprises cable jacket around the multiple conductor logging cable; means for producing data signals from the logging truck; means for modulating the data signals on a radio frequency carrier wave; means for inductively coupling the modulated data signals to the cable jacket for conduction along the cable; and means for receiving the modulated data signals.

Stiner, T.R.

1992-08-18

92

Coal log pipeline pilot plant construction and tests: An update  

Microsoft Academic Search

Coal log pipeline (CLP) is an emerging technology for coal transportation that has many potential values including: (a) it transports twice the amount of coal transported by a coal slurry pipeline of the same diameter; (b) it uses only one-third to one-fourth the water used by a coal slurry pipeline for transporting the same amount of coal; (c) it does

H. Liu; C. W. Lenau; Y. Lin; B. Burkett

1999-01-01

93

Shape of a Towed Boom of Logs  

Microsoft Academic Search

An analysis has been made of the shape of a towed boom of logs in which the logs are treated as a continuum which transmits only normal stresses. If the skin friction between the bottom of the logs and the water is assumed to be constant, the shape of the boom is shown to be one of a single-parameter family

B. G. Newman

1975-01-01

94

BRIDGING THE GREAT DIVIDE - Building Log Books  

Microsoft Academic Search

Summary Better information leads to better buildings! UK Building Regulations now require building log books in new and refurbished buildings. This paper describes the role of building log books in improving buildings by bringing together the design and facilities management communities. It outlines what a log book should include, as indicated by CIBSE TM31, and how they might be used

P G Jones

95

29 CFR 1917.18 - Log handling.  

Code of Federal Regulations, 2013 CFR

...avoid sling damage. (b) Two or more binders or equivalently safe means of containment shall remain on logging trucks and railcars to secure logs during movement of the truck or car within the terminal. During unloading, logs shall be prevented from...

2013-07-01

96

Illegal Logging in Common Property Forests  

Microsoft Academic Search

Community-based forestry has the potential to improve forest management in the commons. Unfortunately, the ease with which logging interests are able to ignore community decisions and steal timber remains troubling. This article analyzes how illegal logging is highly erosive to community cohesiveness and institutions in the context of community forestry in Mexico. It analyzes the modus operandi of clandestine logging

Jordi Honey-Rosés

2009-01-01

97

Learning Logs: Assessment or Research Method?  

Microsoft Academic Search

Learning logs are an increasingly popular mode assessment. They record learning, experience and reflection. This paper considers learning logs as a research method, where researchers wish to gain a deep understanding of the processes of learning, reflection and experience as they occur in individuals over a period of time. Techniques are offered for implementing logs as a research method, analysing

Tim Friesner; Mike Hart

98

Porosity calibration of neutron logs, SACROC unit  

SciTech Connect

A major field study has been initiated at the Scurry Area Canyon Reef Operators Committee (SACROC) unit to provide a detailed geologic description of the reservoir. To supply porosity information to the digital database, a new technique has been developed that transforms neutron deflection logs into accurate neutron porosity logs. The technique uses computer programs to analyze statistically the neutron log to be rescaled as well as nearby modern porosity logs. An equations is derived that transforms neutron log deflection into porosity. Once the porosity response of a particular tool is determined in areas of good porosity control, that response can be applied successfully in areas of little or no control.

Swulius, T.M.

1986-04-01

99

Integrating MDT, NMR log and conventional logs for one-well evaluation  

Microsoft Academic Search

This paper presents a case study for one-well evaluation integrating MDT, NMR logs and conventional logs. MDT, NMR logs and conventional logs provide formation permeability in different ways though the parameter can be derived in the three kinds of data. Integrating the three kinds of data and comparing the change trends among the data, the heterogeneity of reservoir and tiger

Liu Tangyan; Ma Zaitian; Wang Junxiao; Lv Hongzhi

2005-01-01

100

Multi-rate flowing Wellbore electric conductivity logging method  

SciTech Connect

The flowing wellbore electric conductivity logging method involves the replacement of wellbore water by de-ionized or constant-salinity water, followed by constant pumping with rate Q, during which a series of fluid electric conductivity logs are taken. The logs can be analyzed to identify depth locations of inflow, and evaluate the transmissivity and electric conductivity (salinity) of the fluid at each inflow point. The present paper proposes the use of the method with two or more pumping rates. In particular it is recommended that the method be applied three times with pumping rates Q, Q /2, and 2Q. Then a combined analysis of the multi-rate data allows an efficient means of determining transmissivity and salinity values of all inflow points along a well with a confidence measure, as well as their inherent or far-field pressure heads. The method is illustrated by a practical example.

Tsang, Chin-Fu; Doughty, Christine

2003-04-22

101

Log interpretation of shaly sandstones  

SciTech Connect

The determination of water saturation from electrical resistivity measurements to evaluate the potential of reservoirs is a fundamental tool of the oil industry. Shaly sandstones are difficult to evaluate because clays are conductive and they lower the resistivity of the rock. A review of shaly-sandstone research concerning ''volume-of-shale'' equations reveals three theoretical categories: (1) laminated clay equations, (2) dispersed clay equations, and (3) equations that assume that the effect of the clays on the conductivity measurement is directly related to water saturation. A new model for predicting the relative amounts of laminated and dispersed shales and accounting for their effects according to their abundance can be used for any sandstone, clean or shaly. Equations representing each of the three theoretical categories and the new equation were tested on cored Wilcox sandstones from two wells. Cores were analyzed to determine the volume and distribution of clays and to correlate porosity with the well logs.

Baker, J.F.

1988-01-01

102

Analysis of Web Proxy Logs  

NASA Astrophysics Data System (ADS)

Network forensics involves capturing, recording and analysing network audit trails. A crucial part of network forensics is to gather evidence at the server level, proxy level and from other sources. A web proxy relays URL requests from clients to a server. Analysing web proxy logs can give unobtrusive insights to the browsing behavior of computer users and provide an overview of the Internet usage in an organisation. More importantly, in terms of network forensics, it can aid in detecting anomalous browsing behavior. This paper demonstrates the use of a self-organising map (SOM), a powerful data mining technique, in network forensics. In particular, it focuses on how a SOM can be used to analyse data gathered at the web proxy level.

Fei, Bennie; Eloff, Jan; Olivier, Martin; Venter, Hein

103

Leak checker data logging system  

DOEpatents

A portable, high speed, computer-based data logging system for field testing systems or components located some distance apart employs a plurality of spaced mass spectrometers and is particularly adapted for monitoring the vacuum integrity of a long string of a superconducting magnets such as used in high energy particle accelerators. The system provides precise tracking of a gas such as helium through the magnet string when the helium is released into the vacuum by monitoring the spaced mass spectrometers allowing for control, display and storage of various parameters involved with leak detection and localization. A system user can observe the flow of helium through the magnet string on a real-time basis hour the exact moment of opening of the helium input valve. Graph reading can be normalized to compensate for magnet sections that deplete vacuum faster than other sections between testing to permit repetitive testing of vacuum integrity in reduced time.

Gannon, Jeffrey C. (Arlington, TX); Payne, John J. (Waterman, IL)

1996-01-01

104

Pulsed neutron-log applications in California - improved capability via borehole decay correction  

Microsoft Academic Search

In the past, pulsed neutron logs were distorted by fresh water in California oil reservoirs. A new pulsed neutron tool, the TMD, was introduced several years ago. A two-decay-component method is used to calculate the formation capture cross section (sigma). Log examples in California show that fresh water causes low formation sigma values. Large, fresh boreholes also exhibit low borehole

1986-01-01

105

LogTM: log-based transactional memory  

Microsoft Academic Search

Transactional memory (TM) simplifies parallel program- ming by guaranteeing that transactions appear to execute atomically and in isolation. Implementing these properties includes providing data version management for the simul- taneous storage of both new (visible if the transaction com- mits) and old (retained if the transaction aborts) values. Most (hardware) TM systems leave old values \\

Kevin E. Moore; Jayaram Bobba; Michelle J. Moravan; Mark D. Hill; David A. Wood

2006-01-01

106

Log-periodic self-similarity: an emerging financial law?  

NASA Astrophysics Data System (ADS)

A hypothesis that the financial log-periodicity, cascading self-similarly through various time scales, carries signatures of a law is pursued. It is shown that the most significant historical financial events can be classified amazingly well using a single and unique value of the preferred scaling factor /?=2, which indicates that its real value should be close to this number. This applies even to a declining decelerating log-periodic phase. Crucial in this connection is identification of a ``super-bubble'' (bubble on bubble) phenomenon. Identifying a potential ``universal'' preferred scaling factor, as undertaken here, may significantly improve the predictive power of the corresponding methodology. Several more specific related results include evidence that: the real end of the high technology bubble on the stock market started (with a decelerating log-periodic draw down) in the beginning of September 2000; a parallel 2000-2002 decline seen in the Standard & Poor's 500 from the log-periodic perspective is already of the same significance as the one of the early 1930s and of the late 1970s; all this points to a much more serious global crash in around 2025, of course from a level much higher (at least one order of magnitude) than in 2000.

Dro?d?, S.; Grümmer, F.; Ruf, F.; Speth, J.

2003-06-01

107

Log-amplitude statistics for Beck-Cohen superstatistics  

NASA Astrophysics Data System (ADS)

As a possible generalization of Beck-Cohen superstatistical processes, we study non-Gaussian processes with temporal heterogeneity of local variance. To characterize the variance heterogeneity, we define log-amplitude cumulants and log-amplitude autocovariance and derive closed-form expressions of the log-amplitude cumulants for ?2, inverse ?2, and log-normal superstatistical distributions. Furthermore, we show that ?2 and inverse ?2 superstatistics with degree 2 are closely related to an extreme value distribution, called the Gumbel distribution. In these cases, the corresponding superstatistical distributions result in the q-Gaussian distribution with q=5/3 and the bilateral exponential distribution, respectively. Thus, our finding provides a hypothesis that the asymptotic appearance of these two special distributions may be explained by a link with the asymptotic limit distributions involving extreme values. In addition, as an application of our approach, we demonstrated that non-Gaussian fluctuations observed in a stock index futures market can be well approximated by the ?2 superstatistical distribution with degree 2.

Kiyono, Ken; Konno, Hidetoshi

2013-05-01

108

Log-amplitude statistics for Beck-Cohen superstatistics.  

PubMed

As a possible generalization of Beck-Cohen superstatistical processes, we study non-Gaussian processes with temporal heterogeneity of local variance. To characterize the variance heterogeneity, we define log-amplitude cumulants and log-amplitude autocovariance and derive closed-form expressions of the log-amplitude cumulants for ?(2), inverse ?(2), and log-normal superstatistical distributions. Furthermore, we show that ?(2) and inverse ?(2) superstatistics with degree 2 are closely related to an extreme value distribution, called the Gumbel distribution. In these cases, the corresponding superstatistical distributions result in the q-Gaussian distribution with q=5/3 and the bilateral exponential distribution, respectively. Thus, our finding provides a hypothesis that the asymptotic appearance of these two special distributions may be explained by a link with the asymptotic limit distributions involving extreme values. In addition, as an application of our approach, we demonstrated that non-Gaussian fluctuations observed in a stock index futures market can be well approximated by the ?(2) superstatistical distribution with degree 2. PMID:23767484

Kiyono, Ken; Konno, Hidetoshi

2013-05-06

109

QX(hyq-bar mesons in the leading-log and leading-log-log models  

SciTech Connect

We use a renormalization-group-improved local effective action of QCD to describe mesons that contain one heavy quark (D,F,B,F/sub b/,T,F/sub t/). We find a self-consistent Abelian solution to the classical equations of motion. The wave function of the light quark is obtained from solving the Dirac equation in the Abelian Coulomb-type field of the heavy quark, with the boundary condition psi-barpsiVertical Bar/sub R/ = 0. The radius R is obtained from the minimization of the total energy of the system U(R). The recoil of the heavy quark as well as its color-magnetic moment are treated as small perturbations. The only parameters are the unavoidable: the quark masses and ..lambda../sub MS$/, where MS is the modified minimal subtraction scheme. Our system exhibits linear confinement. For ..lambda../sub MS$/ = 270 MeV, our string tension is sigmaequivalentdU/d(/sup 1/2/)Vertical Bar/sub Rarrow-rightinfinity/ = ( 378 MeV)/sup 2/ in the log-log model. We obtain good agreement with all known spectroscopy using m/sub u/ = m/sub d/ = 0, m/sub s/ = 0.215 GeV, m/sub c/ = 1.60 GeV, and m/sub b/ = 5.00 GeV. Predictions are made for as yet unobserved spectroscopy as well as for the rms radii of the mesons. We estimate the rates for electromagnetic transitions (M(..-->..M+..gamma..), leptonic decays (M..-->..l..nu..), and single-pion emission (M(..-->..M+..pi..). Good agreement is found for the rates that have been measured.

Margolis, B.; Mendel, R.R.; Trottier, H.D.

1986-05-01

110

Frac packs complicate PNC log evaluation  

SciTech Connect

Borate-crosslinked fluids and/or ceramic proppants commonly included in frac-pack well completions can compliance pulsed neutron capture (PNC) log evaluation. PNC logs are routinely run in cased holes. Two common applications include identifying formation fluid and calculating the percent water saturation in the rock pore spaces near the well bore. The paper discusses PNC logs, a case history of a West Delta oil well, laboratory work, and results. Recommendations are given.

Bean, C.L.; Ali, S.A. [Chevron U.S.A. Production Co., New Orleans, LA (United States); Salaita, G.N. [Chevron Petroleum Technology Co., Houston, TX (United States)

1996-12-23

111

Frac packs complicate PNC log evaluation  

Microsoft Academic Search

Borate-crosslinked fluids and\\/or ceramic proppants commonly included in frac-pack well completions can compliance pulsed neutron capture (PNC) log evaluation. PNC logs are routinely run in cased holes. Two common applications include identifying formation fluid and calculating the percent water saturation in the rock pore spaces near the well bore. The paper discusses PNC logs, a case history of a West

C. L. Bean; S. A. Ali; G. N. Salaita

1996-01-01

112

Intelligent Technology for Well Logging Analysis  

Microsoft Academic Search

Well logging analysis plays an essential role in petroleum exploration and exploitation. It is used to identify the pay zones\\u000a of gas or oil in the reservoir formations. This paper applies intelligent technology for well logging analysis, particular\\u000a combining data mining and expert system together, and proposes an intelligent system for well log analysis called IntWeL Analyzer\\u000a in terms of

Zhongzhi Shil; Ping Luol; Yalei Hao; Guohe Li; Markus Stumptner; Qing He; Gerald Quirchmayr

2004-01-01

113

Coal log pipeline pilot plant construction and tests: An update  

SciTech Connect

Coal log pipeline (CLP) is an emerging technology for coal transportation that has many potential values including: (a) it transports twice the amount of coal transported by a coal slurry pipeline of the same diameter; (b) it uses only one-third to one-fourth the water used by a coal slurry pipeline for transporting the same amount of coal; (c) it does not require expensive slurry pumps; (d) dewatering of slurry at the pipeline outlet is much simpler for CLP than slurry pipelines; (e) there is no restart problem; (f) it is adaptable to drag reduction by using polymers and hence is energy efficient; (g) it eliminates air and land polluting problems caused by coal transportation by truck or train; (h) it completely eliminates spontaneous combustion during coal transportation and storage at power plants; (i) it eliminates highway congestion and accidents caused by coal trucks, and eliminates accidents and traffic jam at rail crossings caused by coal trains; (j) it is more economical to use CLP than to use truck and trains to transport coal in many circumstances. Since 1991, extensive research in CLP has been conducted at Capsule Pipeline Research Center (CPRC), University of Missouri-Columbia. The research has been sponsored by the National Science Foundation, U.S. Department of Energy, Missouri Department of Economic Development, Electric Power Research Institute (EPRI), and an industry consortium of two dozen companies. The R and D resulted in rapid advancement of the CLP technology. After a pilot plant testing of a complete CLP system, the CLP technology will be ready for commercial use. The pilot plant consists of: (a) A coal log machine that can mass produce 5.4-inch diameter coal logs; (b) A 6-inch-diameter steel pipe 3,000 ft long, equipped with a special pumping system that allows coal logs to bypass the pump unhindered (Being a closed loop, the pipeline can recirculate coal logs through the system indefinitely, for testing coal log abrasion resistance over any distance.); (c) A coal log injection system that can inject long trains (each consisting of 100 logs) into the pipe for testing; (d) A coal log ejection system that can eject the coal logs from the pipe after testing; and (e) An automatic control system for the pipeline, consisting of sensors and computers (PLCs and a SCADA). At the time of writing this abstract (November, 1998), the pilot plant is more than half completed the coal log machine has been built and the pipeline is under construction. The entire system will be completed in Spring 1999, followed by various tests. This paper, to be submitted in June 1999, will contain details on the CLP pilot plant construction and the results of preliminary tests. The test results will cover coal log manufacturing (compaction), coal log abrasion tests in the 6-inch pipe, and test of drag reduction in the 6-inch pipe.

Liu, H.; Lenau, C.W.; Lin, Y.; Burkett, B.

1999-07-01

114

Flow rate logging seepage meter  

NASA Astrophysics Data System (ADS)

An apparatus for remotely measuring and logging the flow rate of groundwater seepage into surface water bodies is described. As groundwater seeps into a cavity created by a bottomless housing, it displaces water through an inlet and into a waterproof sealed upper compartment, at which point, the water is collected by a collection bag, which is contained in a bag chamber. A magnet on the collection bag approaches a proximity switch as the collection bag fills, and eventually enables the proximity switch to activate a control circuit. The control circuit then rotates a three-way valve from the collection path to a discharge path, enables a data logger to record the time, and enables a pump, which discharges the water from the collection bag, through the three-way valve and pump, and into the sea. As the collection bag empties, the magnet leaves the proximity of the proximity switch, and the control circuit turns off the pump, resets the valve to provide a collection path, and restarts the collection cycle.

Reay, William G.; Walthall, Harry G.

1992-12-01

115

Trees and Logs Important to Wildlife in the Interior Columbia River Basin.  

National Technical Information Service (NTIS)

This publication provides qualitative and quantitative information on five distinct structures: living trees with decayed parts, trees with hollow chambers, trees with brooms, dead trees, and logs. Information is provided on the value of these structures ...

E. L. Bull C. G. Parks T. R. Torgersen

1997-01-01

116

Discover Presidential Log Cabins. Teacher's Discussion Guide.  

ERIC Educational Resources Information Center

|Discover Presidential Log Cabins is a set of materials designed to help educate 6-8 grade students about the significance of three log cabin sites occupied by George Washington, Ulysses Grant, Abraham Lincoln, and Theodore Roosevelt. This teacher's discussion guide is intended for use as part of a larger, comprehensive social studies program, and…

National Park Service (Dept. of Interior), Washington, DC.

117

Distortion in resistivity logging at shallow depth  

Microsoft Academic Search

Owing to the proximity of an insulating ground surface, normal resistivity logging at shallow depths (less than 30 m) can yield an apparent resistivity that exceeds 200% of the formation resistivity for a homogeneous medium. The distortion is more acute for long-normal than for short-normal logging. Three examples from a landfill site in southern California are presented to show such

Tien-Chang Lee; B. N. Damiata

1995-01-01

118

Field tests of cement bond logging tools  

Microsoft Academic Search

A field test of one company's various Cement Bond Log tools was run to evaluate the effect of varying signal frequencies and tool diameters. Two larger diameter sondes with different frequencies were run and results are presented. One higher frequency, smaller diameter tool was run and results are compared with the other logs. Problems that occurred during the test (and

P. E. Pilkington; W. H. Fertl

1975-01-01

119

29 CFR 1918.88 - Log operations.  

Code of Federal Regulations, 2013 CFR

...shall be provided as follows: 11 A âwalking stickâ is two logs bolted or otherwise secured together with two or three planks firmly attached on top that serves as a floating walking and working surface and that is used in the loading of logs onto...

2013-07-01

120

Learning Logs in Introductory Literature Courses  

ERIC Educational Resources Information Center

This article explores the beneficial and sometimes unpredictable implications of a daily reflective writing exercise for introductory literature courses: the learning log. Pseudonymous samples of student writing, coupled with instructor commentary, gesture toward ways in which the learning log's continual implementation and modification foster a…

Babcock, Matthew James

2007-01-01

121

Wideband, planar, log-periodic balun  

Microsoft Academic Search

This paper presents the design and performance characteristics of a new planar balun structure. The design is based on the log-periodic antenna theory. The design guidelines, as well as simulated and measured results are presented. It is shown that the new balun has greater than one octave bandwidth. The log-periodic balun will find applications in wireless communication circuits such as

Mahmoud Basraoui; S. N. Prasad

1998-01-01

122

People's Query Logs: Personal Information Management  

Microsoft Academic Search

In this position paper we propose that the challenge for query log analysis goes beyond mapping navigation patterns to provide interaction analysis tools to help people understand their own Web search and information behaviors. The relationship between personal information management and Web logs is also discussed. Further research issues are outlined.

Amanda Spink; Bernard J. Jansen

123

Data logging technology in ambulatory medical instrumentation  

Microsoft Academic Search

This paper reviews the advancements made in ambulatory data logging used in the study of human subjects since the inception of the analogue tape based data logger in the 1960s. Research into the area of ambulatory monitoring has been rejuvenated due to the development of novel storage technologies during the 1990s. Data logging systems that were previously impractical due to

R Anderson; G M Lyons

2001-01-01

124

User 4XXXXX9: Anonymizing Query Logs  

Microsoft Academic Search

The recent release of the American Online (AOL) Query Logs highlighted the remarkable amount of private and identifying information that users are willing to reveal to a search engine. The release of these types of log files therefore represents a significant liability and compromise of user privacy. However, without such data the academic community greatly suffers in their ability to

Eytan Adar

2007-01-01

125

Query log analysis: social and technological challenges  

Microsoft Academic Search

Analysis of search engine query logs is an important tool for developers and researchers. However, the potentially personal content of query logs raises a number of questions about the use of that data. Privacy advocates are concerned about potential misuse of personal data; search engine providers are interested in protecting their users while maintaining a competitive edge; and academic researchers

G. Craig Murray; Jaime Teevan

2007-01-01

126

Data logging and inquiry learning in science  

Microsoft Academic Search

This paper describes the postgraduate training of teachers in data logging and inquiry learning in science. Many of these teachers work at primary level and most have no background in science. Working in groups the teachers are given scientific questions of varying degrees of openness and personal relevance, that they are to investigate with the assistance of data logging. Although

John Gipps

2002-01-01

127

Permanence of the LOG-Normal Distribution.  

National Technical Information Service (NTIS)

The distribution of the sum of log-normal variates is shown for most cases of interest to be very accurately represented by a log-normal distribution instead of a normal or Rayleigh distribution that might be expected from the central limit theorem. As a ...

R. L. Mitchell

1968-01-01

128

Water production logging in horizontal wells  

Microsoft Academic Search

New technology has enabled operators to drill an increasing number of extended reach, lateral, and horizontal wells. In these highly deviated or horizontal wells, conventional production logging sensors can be ambiguous in resolving multiphase flows. The successful diagnosis and treatment of water or gas production problems requires the identification of these specific influx zones. Providing reliable production logging solutions in

C. W Morris; C. P Lenn; I. J Albertin

1999-01-01

129

Strong Approximation on LOG Dense Sets.  

National Technical Information Service (NTIS)

Extensions of classical probability limit theorems involving log average and log density are considered. The purpose is to extend Fisher's approximation theorem to i.i.d. sequences the set X(n) with EX (upper bound 2, lower bound 1) + infinity belonging t...

I. Berkes H. Dehling

1991-01-01

130

Coal-log pipeline system development  

SciTech Connect

Project tasks include: (1) Perform the necessary testing and development to demonstrate that the amount of binder in coal logs can be reduced to 8% or lower to produce logs with adequate strength to eliminate breakage during pipeline transportation, under conditions experienced in long distance pipeline systems. Prior to conducting any testing and demonstration, grantee shall perform an information search and make full determination of all previous attempts to extrude or briquette coal, upon which the testing and demonstration shall be based. (2) Perform the necessary development to demonstrate a small model of the most promising injection system for coal-logs, and tests the logs produced. (3) Conduct economic analysis of coal-log pipeline, based upon the work to date. Refine and complete the economic model. (VC)

Liu, H.

1991-12-01

131

Logging conflicts in Southern Cameroon: A feminist ecological economics perspective  

Microsoft Academic Search

Growing attention has been paid to gender in ecological economics, political ecology and development studies but a focus on gender in resource extraction conflicts is still rare. This article explores women-led resistance movements to commercial logging in South-eastern Cameroon, focusing on the moabi tree (Baillonella toxisperma). The latter provides oil, medicine and other non-timber products and use-values to local forest

Sandra Veuthey; Julien-François Gerber

2010-01-01

132

The Rule of Five revisited: applying log D in place of log P in drug-likeness filters.  

PubMed

The much publicized "Rule of 5" has been widely adopted among the pharmaceutical industry. It is used as a first step filter to perform virtual screening of compound libraries, in an effort to quickly eliminate lead candidates that have poor physicochemical properties for oral bioavailabilty. One of the key parameters used therein is log P, which is a useful descriptor, but one that fails to take into account variation in the lipophilicity of a drug with respect to the ionic states present at key biological pH values. Given that the majority of commercial pharmaceuticals contain an ionizable moiety, we propose that log D is a better descriptor for lipophilicity in the context of the Rule of 5. It gives more physiologically relevant results, thereby reducing the number of potential false-negatives incorrectly eliminated in screening. Using a series of commercial compound libraries, this study showed that the adapted Rule of 5 using log D instead of log P provides notable improvement in pass rate for compounds that have the desired lipophilicity at a relevant physiological pH. PMID:17530776

Bhal, Sanjivanjit K; Kassam, Karim; Peirson, Ian G; Pearl, Greg M

2007-05-26

133

ProcintLog: A GUI Academic Software For Open Hole Well-Logging Analysis  

NASA Astrophysics Data System (ADS)

ProcintLog is a GUI academic software that runs under MATLAB and is useful for simplified conventional oil and gas well logs analysis. It works through two distinct modes: (1) direct petrophysical parameters inclusion from both field copies and digital files and (2) by reading and filling data from visual log zoning. The software load ASCII and LAS format files and identifies the logs available, supplying both a header file with additional information about the well and a matrix that depicts the depth in the first column and the logs in the remain ones. The last can be loaded by ProcintLog and checked out for unusual highly noisy and spurious data, which allows a complete data control. Furthermore, each one of the proposed processing modes fits well to any chosen processing sequence, allowing the log interpreter to direct your own necessities into log analysis. To provide a little of perspective, fundamental well-logging principles are stressed by informative icons that can be searched at any time the interpreter need. Calculations such as invasion-corrected resistivity, shale volume, Archie and Simandoux methods for water saturation computations and three types of water resistivity computations are viable. One complete example is performed on both synthetic and real data and results are checked against visual analysis to show the usefulness, rapidness and accuracy of ProcintLog in performing accurate logs analysis.

Silva, J. C.

2005-05-01

134

Sedimentological analysis using geophysical well logs  

SciTech Connect

The application of geophysical well logs in sedimentology and stratigraphic prospecting holds great promise in solving a number of geological problems. A suite of logs provides data on a wide range of rock properties: vertical and lateral variation of resistivity, natural polarization, natural and induced radioactivity, shear strength, and acoustic properties. Each of these properties is controlled by the depositional environment of the sediments and their later diagenesis. The attention of geologists and geophysicists is drawn to new techniques in the interpretation of geophysical well logs for exploration, appraisal, and development of oil and gas fields. The relationship between geophysical logs and depositional environments is explored. Bulk composition, rock structure, and texture and facies variation can be quantified by electric log parameters. Also, the possibility of using logs to demonstrate long- and short-period sedimentary cycles is demonstrated. Methods of sedimentological analysis using geophysical well logs are demonstrated. The importance of a genetic approach in the interpretation of geological sequences and paleogeological reconstructions is emphasized using examples taken from oil and gas prospecting operations in the Ukraine.

Izotova, T.S. (Ukrainian State Geological Research Institute, Kiev (Ukraine))

1993-09-01

135

D-dimensional log gravity  

SciTech Connect

We study Einstein gravity in dimensions D{>=}4 modified by curvature squared at critical point where the theory contains only massless gravitons. We show that at the critical point a new mode appears leading to a logarithmic gravity in the theory. The corresponding logarithmic solution may provide a gravity description of logarithmic conformal field theories (CFT) in higher dimensions. We note also that for special values of the parameters of the theory, the model admits solutions with nonrelativistic isometries.

Alishahiha, Mohsen; Fareghbal, Reza [School of physics, Institute for Research in Fundamental Sciences (IPM), P. O. Box 19395-5531, Tehran (Iran, Islamic Republic of)

2011-04-15

136

The cost of carbon retention by reduced impact logging  

Microsoft Academic Search

Reduced impact logging (RIL) is one means of reducing the carbon emissions held responsible for global warming. It may also reduce other adverse logging effects. A study of RIL’s effects in Sabah, Malaysia, found 44% reduction of area logged within a tract, 22% reduction in timber yield per logged hectare, and 18% increase in cost per m3 logged compared with

John R. Healey; Colin Price; John Tay

2000-01-01

137

Logging effects on soil moisture losses  

Treesearch

Title: Logging effects on soil moisture losses ... of soil moisture within the surface 15 feet by an isolated mature sugar pine and an adjacent uncut ... required for the wetting front to progress through the unsaturated zone above the water table.

138

Selective logging and its relation to deforestation  

Treesearch

International Institute of Tropical Forestry ... Title: Selective logging and its relation to deforestation. Author: Asner ... This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.

139

CMLOG: A common message logging system  

SciTech Connect

The Common Message Logging (CMLOG) system is an object-oriented and distributed system that not only allows applications and systems to log data (messages) of any type into a centralized database but also lets applications view incoming messages in real-time or retrieve stored data from the database according to selection rules. It consists of a concurrent Unix server that handles incoming logging or searching messages, a Motif browser that can view incoming messages in real-time or display stored data in the database, a client daemon that buffers and sends logging messages to the server, and libraries that can be used by applications to send data to or retrieve data from the database via the server. This paper presents the design and implementation of the CMLOG system meanwhile it will also address the issue of integration of CMLOG into existing control systems.

Chen, J.; Akers, W.; Bickley, M.; Wu, D.; Watson, W. III [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States). Control Software Group

1997-12-01

140

Using Work Sampling to Analyze Logging Operations.  

National Technical Information Service (NTIS)

The report discusses the advantages and disadvantages of various time study methods for determining efficiency and productivity in logging. The work sampling method is compared with the continuous time-study method; gives the feasibility, capability, and ...

E. S. Miyata H. M. Stienhib S. A. Winsauer

1981-01-01

141

Formation mechanical properties and the sonic log  

SciTech Connect

A program is presented that calculates the mechanical properties of reservoir rocks from sonic logs. The program was written in Microsoft BASIC and the source code for MS-DOS, Apple Macintosh, and Amiga personal computers is given.

Elphick, R.Y.

1988-11-01

142

Logging safety in forest management education - Treesearch  

Treesearch

... for careers in forestry by teaching a combination of biological sciences (e.g., silvics ... This paper illustrates the ethical and economic importance of logging safety to ... and advocates incorporating safety issues into existing forestry courses.

143

Logging-while-coring method and apparatus  

DOEpatents

A method and apparatus for downhole coring while receiving logging-while-drilling tool data. The apparatus includes core collar and a retrievable core barrel. The retrievable core barrel receives core from a borehole which is sent to the surface for analysis via wireline and latching tool The core collar includes logging-while-drilling tools for the simultaneous measurement of formation properties during the core excavation process. Examples of logging-while-drilling tools include nuclear sensors, resistivity sensors, gamma ray sensors, and bit resistivity sensors. The disclosed method allows for precise core-log depth calibration and core orientation within a single borehole, and without at pipe trip, providing both time saving and unique scientific advantages.

Goldberg, David S. (New York, NY); Myers, Gregory J. (Cornwall, NY)

2007-11-13

144

Log-based transactional workflow mining  

Microsoft Academic Search

A continuous evolution of business process parameters, constraints and needs, hardly foreseeable initially, requires a continuous\\u000a design from the business process management systems. In this article we are interested in developing a reactive design through\\u000a process log analysis ensuring process re-engineering and execution reliability. We propose to analyse workflow logs to discover\\u000a workflow transactional behaviour and to subsequently improve and

Walid Gaaloul; Khaled Gaaloul; Sami Bhiri; Armin Haller; Manfred Hauswirth

2009-01-01

145

Conversation Threads Hidden within Email Server Logs  

NASA Astrophysics Data System (ADS)

Email server logs contain records of all email Exchange through this server. Often we would like to analyze those emails not separately but in conversation thread, especially when we need to analyze social network extracted from those email logs. Unfortunately each mail is in different record and those record are not tided to each other in any obvious way. In this paper method for discussion threads extraction was proposed together with experiments on two different data sets - Enron and WrUT..

Palus, Sebastian; Kazienko, Przemys?aw

146

New technology applied to well logging  

Microsoft Academic Search

Remote locations and increasingly complex geology require a higher level of sophistication in well-logging equipment and services. Applying technological advancements, well-logging contractors have developed a variety of new products and services designed to provide better quality data at reasonable prices. One of the most significant technological breakthroughs has been in satellite communications. Denver-based Western Tele-Communications Inc. is one of the

Stremel

1984-01-01

147

DOE/Simplec magnetic susceptibility logging system  

SciTech Connect

A magnetic susceptibility logging system has been developed which is relatively stable under normal field logging conditions and which produces logs that accurately represent in situ variations in magnetic susceptibility. However, both field and laboratory tests indicate the need for further improvement of temperature stabilization and bridge compensation; a new generation system designed by Simplec may fill that need. A cubic granite block with a magnetic susceptibility of 385 ..mu..CGS is designated as the primary calibration standard and is available for public use at the DOE facility in Grand Junction, Colorado. Models are also available for characterization of magnetic susceptibility systems. These include models to provide borehole size correction factors, thin layer interpretation parameters, reproducibility limits, longitudinal resolution, and radius of investigation. The DOE/Simplec system has a 99-percent radius of investigation, approximately equal to the coil length (15 inches), and a 99-percent thickness of investigation, approximately equal to two coil lengths. The true magnetic susceptibility and thickness of isolated layers less than two coil lengths in thickness can be obtained through use of parameters measured from their log responses. Field tests show that the system has a reproducibility of at least 5 ..mu..CGS and that logging at 25 ft/min is a good compromise between speed of operation and keeping the probe on the sidewall. Comparison of log and core magnetic susceptibility measurements confirms the fact that the logging system samples a rather large volume and that interpretive aids are necessary to unfold the true variation of magnetic susceptibility with depth. Finally, logs from known uranium-favorable environments show that magnetic susceptibility measurements can give an indication of the degree of geochemical alteration, which is one of the uranium-favorable haloes sought by exploration geologists.

Emilia, D.A.; Allen, J.W.; Chessmore, R.B.; Wilson, R.B.

1981-03-01

148

Planar channelized log-periodic antenna  

Microsoft Academic Search

We present the design, simulation, and measurement of a dual linearly polarized log-periodic antenna matched to a log-periodic channelizing filter through a tapered microstrip balun. The design can be implemented monolithically. A prototype of the channelized antenna, which operates over 1 - 5 GHz, is realized on printed circuit board with a dielectric constant of 4.5. Because we designed the

G. Engargiola; W. Holzapfel; A. Lee; M. J. Myers; R. O'Brient; P. L. Richards; H. Tran; H. Spieler

2005-01-01

149

47 CFR 73.1840 - Retention of logs.  

Code of Federal Regulations, 2010 CFR

...claims. (b) Logs may be retained...data-storage systems subject to the...Reproduction of logs, stored on data-storage systems, to full-size...requirements relating to logs). (ii) After...data-storage system, by...

2009-10-01

150

47 CFR 73.1840 - Retention of logs.  

Code of Federal Regulations, 2010 CFR

...claims. (b) Logs may be retained...data-storage systems subject to the...Reproduction of logs, stored on data-storage systems, to full-size...requirements relating to logs). (ii) After...data-storage system, by...

2010-10-01

151

Environmental Effects of Postfire Logging: Literature Review and Annotated Bibliography.  

National Technical Information Service (NTIS)

The scientific literature on logging after wildfire is reviewed, with a focus on environmental effects of logging and removal of large woody structure. Rehabilitation, the practice of planting or seeding after logging, is not reviewed here. Several public...

J. D. McIver L. Starr

2000-01-01

152

Values and Moral Values  

Microsoft Academic Search

\\u000a The vertical table of values and disvalues according to their relative worth that was presented in Chap. 2 as part of Scheler’s\\u000a phenomenology of cognitive acts of feeling and preference is now developed by Hartmann in several dimensions. He (1) distinguishes\\u000a moral values and non-moral values; (2) studies how some of the latter’s contents causally condition the content of the

Eugene Kelly

153

Sorption and ecotoxicity of pentachlorophenol polluted sediment amended with rice-straw derived biochar  

Microsoft Academic Search

To investigate the feasibility of using biochar to control organic pollutants in sediments, we extracted biochar from rice-straw combustion residues (RBC) and studied its adsorption ability and effect on seed germination ecotoxicity of pentachlorophenol (PCP). The results showed that the Freundlich and dual-mode models could describe all the sorption isotherm data well, and the log KOC values increased with increasing

Liping Lou; Binbin Wu; Lina Wang; Ling Luo; Xinhua Xu; Jiaai Hou; Bei Xun; Baolan Hu; Yingxu Chen

2011-01-01

154

Inverting fluid conductivity logs for fracture inflow parameters  

NASA Astrophysics Data System (ADS)

Fluid electrical conductivity logging experiments introduced by Tsang et al. [1990] represent a new technology for studying the hydraulic properties of discrete fractures in open boreholes. These experiments consist of replacing water in the well bore with deionized water and then pumping the well to induce formation water to return to the well bore. During and after the fluid exchange the entire well is logged to measure fluid electrical conductivity (FEC). At locations where formation water enters the well there are abrupt increases in the borehole FEC, thereby revealing the location of hydraulically conductive fractures. As pumping continues, high FEC water moves up the well bore at a rate proportional to the total inflow rate below the observation point. Inflow rates and FECs of formation water associated with each fracture can be inferred by modeling the FEC profiles with the one-dimensional advective dispersion equation. In this paper I present an inverse model which estimates the inflow rates and formation FEC values that optimally fit observed FEC logs acquired during fluid exchange experiments described by Tsang et al. [1990]. With this inverse model, inflow rates are constrained by the rate at which the well is pumped during the experiment. The forward model is solved numerically using a control volume finite difference scheme with power law upstream weighting and source term linearization. The inverse problem is solved using the Gauss-Newton iterative method. The rows of the Jacobian matrix, or the sensitivity coefficients, are calculated numerically with the same algorithm that solves the forward problem. Both constrained and unconstrained inverse models are used to interpret fluid logging experiments performed in research wells penetrating Piedmont rocks of North Carolina.

Evans, David G.

155

Chiral logs and the quenched approximation on the lattice  

NASA Astrophysics Data System (ADS)

The phenomenological success of the quenched approximation has been impressive in obtaining accurate results for the mass spectrum and other aspects of hadron structure. However, an independent theoretical estimate of the systematic error introduced by quenching is still missing. To this end, it can be useful to consider chiral theories which, at the one-loop level, introduced peculiar non analytical terms (the so-called chiral logs). Sharpe showed that when this framework is adapted to the quenched approximation, the dependence of the pion mass squared on the quark mass can be described by an anomalous power ? (the 'hairpin' diagram on the pion mass shell) associated with flavor singlet loops and enhanced chiral logs. Treating the hairpin as a momentum independent mass insertion, he estimated ??0.2. However, numerical calculations in quenched lattice quantum chromodynamics show little or no evidence for chiral logs at such a level. The following work determines the anomalous power numerically by studying the pion mass as a function of the bare quark mass, as well as its volume dependence. Sources of systematic error are carefully examined. Last, the coefficient of the chiral log is calculated from the two quark-loops pion propagator. The results consistently indicate a value for the anomalous power that is approximately one order of magnitude smaller than the earlier theoretical estimate, in particular/delta = 0.013(2)From this one can see that for all pion masses considered, the systematic error introduced by quenching is small and always within the statistical error. Finally, by a direct calculation of the topological susceptibility of the lattice configurations, I conclude that the reason why the anomalous power is so small is a strong momentum dependence giving rise to a suppression of the hairpin at momenta comparable with the pion mass.

Perrucci, Stefania

1997-12-01

156

Post-Wildfire (Salvage) Logging - The Controversy  

NSDL National Science Digital Library

This module is the fifth in the Fire Ecology and Management Series. The question of whether or not to remove trees after a wildfire is among the most contentious issues related to wildfire management. This lecture-based module examines our current state of knowledge on post-fire salvage logging and restoration. A PowerPoint presentation describes the arguments in support of, and those in opposition to, salvage logging. These arguments are then evaluated in the context of findings from recent scientific investigations. This research challenges some long-held beliefs regarding the benefits of salvage logging as a tool of post-fire management. Students are asked to develop their own views on this complex issue.

2010-08-19

157

Spreadsheet log analysis in subsurface geology  

USGS Publications Warehouse

Most of the direct knowledge of the geology of the subsurface is gained from the examination of core and drill-cuttings recovered from boreholes drilled by the petroleum and water industries. Wireline logs run in these same boreholes generally have been restricted to tasks of lithostratigraphic correlation and thee location of hydrocarbon pay zones. However, the range of petrophysical measurements has expanded markedly in recent years, so that log traces now can be transformed to estimates of rock composition. Increasingly, logs are available in a digital format that can be read easily by a desktop computer and processed by simple spreadsheet software methods. Taken together, these developments offer accessible tools for new insights into subsurface geology that complement the traditional, but limited, sources of core and cutting observations.

Doveton, J. H.

2000-01-01

158

LogSafe and Smart: Minnesota OSHA's LogSafe Program Takes Root.  

ERIC Educational Resources Information Center

Logging is now the most dangerous U.S. occupation. The Occupational Safety and Health Administration (OSHA) developed specialized safety training for the logging industry but has been challenged to reach small operators. An OSHA-approved state program in Minnesota provides annual safety seminars to about two-thirds of the state's full-time…

Honerman, James

1999-01-01

159

LIS is More: Improved Diagnostic Logging in Sensor Networks with Log Instrumentation Specifications  

Microsoft Academic Search

Detailed diagnostic data is a prerequisite for de- bugging problems and understanding runtime performance in distributed embedded wireless systems. Severe bandwidth lim- itations, tight timing constraints, and limited program text space hinder the application of standard diagnostic tools within this domain. Our work introduces the Log Instrumentation Specification (LIS) that drives insertion of low overhead logging calls into a system.

Roy She; Mani Srivastava

160

LogSafe and Smart: Minnesota OSHA's LogSafe Program Takes Root.  

ERIC Educational Resources Information Center

|Logging is now the most dangerous U.S. occupation. The Occupational Safety and Health Administration (OSHA) developed specialized safety training for the logging industry but has been challenged to reach small operators. An OSHA-approved state program in Minnesota provides annual safety seminars to about two-thirds of the state's full-time…

Honerman, James

1999-01-01

161

Algorithm 762: LLDRLF, log-likelihood and some derivatives for log-F models  

Microsoft Academic Search

The flexible statistical models incorporating the log-F distribution are little used because of numeric difficulties. We describe a method for calculating the log-likelihood and two derivatives with respect to the data argument. Fortran subroutines incorporating these calculations are provided.

Barry W. Brown; Lawrence B. Levy; James Lovato; Kathy Russell; Floyd M. Spears

1996-01-01

162

Wave functions of log-periodic oscillators  

SciTech Connect

We use the Lewis and Riesenfeld invariant method [J. Math. Phys. 10, 1458 (1969)] and a unitary transformation to obtain the exact Schroedinger wave functions for time-dependent harmonic oscillators exhibiting log-periodic-type behavior. For each oscillator we calculate the quantum fluctuations in the coordinate and momentum as well as the quantum correlations between the coordinate and momentum. We observe that the oscillator with m=m{sub 0}t/t{sub 0} and {omega}={omega}{sub 0}t{sub 0}/t, which exhibits an exact log-periodic oscillation, behaves as the harmonic oscillator with m and {omega} constant.

Bessa, V.; Guedes, I. [Departamento de Fisica, Universidade Federal do Ceara, Campus do Pici, Fortaleza, CE 60455-760 (Brazil)

2011-06-15

163

Estimating xenobiotic half-lives in humans from rat data: influence of log P.  

PubMed Central

The nature of empirical allometric expressions relating dispositional and kinetic parameters for a given xenobiotic across multiple mammalian species is well known. It has also been demonstrated that a simple allometric relationship may be used to predict kinetic parameters for humans based merely on data for multiple xenobiotics from rats. We decided to explore reasons for the variance in the data arising from the latter method. We were particularly interested in learning whether any physicochemical characteristics of xenobiotics might account for outlying data points (i.e., poor prediction of human half-life from rat half-life). We have explored the influence of lipid solubility as reflected by a xenobiotic's log P value because adipose tissue comprises a significantly larger percentage of total body weight in humans than in rats. We used half-life data from the literature for 127 xenobiotics. A data subset of 102 xenobiotics for which we were able to find estimates of log P values, including several with extremely large log P values, was also analyzed. First and second order models, including and excluding log P, were compared. The simplest of these models can be recast as the familiar allometric relationship having the form Y = a(Xb). The remaining models can be seen as extensions of this relationship. Our results suggest that incorporation of log P into the prediction of xenobiotic half-life in humans from rat half-life data is important only for xenobiotics with extremely large log P values such as dioxins and polychlorinated biphenyls. Moreover, a second order model in logarithm of rat half-life accommodates all data points very well, without specifically accounting for log P values. Images Figure 1. Figure 2. Figure 3. A Figure 3. B Figure 3. C Figure 3. D Figure 4.

Sarver, J G; White, D; Erhardt, P; Bachmann, K

1997-01-01

164

Optimal simple step-stress plan for cumulative exposure model using log-normal distribution  

Microsoft Academic Search

Optimal times of changing stress level for simple step-stress plans under a cumulative exposure model using the log-normal distribution are determined for a wide range of values of the parameters in the model. A table of optimal times of changing stress level for various model parameters values is obtained. A formula for optimal time of changing stress level is also

Abdulla A. Alhadeed; Shie-shien Yang

2005-01-01

165

Conserving Forest Wildlife and Other Ecosystem Services: Opportunity Costs and The Valuation of Alternative Logging Regimes  

Microsoft Academic Search

Ecosystems supply a wide variety of valued commodities, including ecological services. Valuing these commodities and determining the implications of their valuation for the optimal management of ecosystems is challenging. This paper considers the optimal spatial use of forest ecosystems given that they can be utilised for conserving wildlife species and for producing logs. It takes into account the alternatives of

Clement A. Tisdell

2012-01-01

166

The scale-up behavior of coal logs for the coal log pipeline technology  

NASA Astrophysics Data System (ADS)

Coal Log Pipeline (CLP) refers to a new technology for the transportation of coal, which has been developing in the USA over the past several years, and is expected to be used on a commercial scale within the next few years. In a CLP system, coal is prepared in the form of circular cylinders, coal logs, so that the coal can be transported through an underground or overland pipeline. One of the major requirements in the CLP technology is to produce strong and durable coal logs, which can endure a long distance trip through water pipelines without breaking and with a minimum amount of weight loss. To reach this goal, research has taken place on several fabrication methods, such as compaction and extrusion, and good-quality coal logs with a diameter range of 1.8-in. to 5.4-in. have been made, using a simple compaction technique. However, for a commercial application, the size (diameter) of coal logs is expected to be much larger than the range studied in this research, therefore, the relationship in terms of quality between small and large coal logs needs to be investigated in both fabrication process and pipeline transportation operation. This dissertation describes the research work conducted on investigating scale-up behavior of coal logs during fabrication and pipeline transportation, based on the experiments from two different size coal log and pipeline loop systems. The research work covers the scaling-up effect on the strength from 1.8-in. to 5.4-in. coal logs, and on the coal log wearability during pipeline transportation from a 2-in. and a 6-in. loop.

Zhao, Bing

2000-11-01

167

Client-Based Logging for High Performance Distributed Architectures  

Microsoft Academic Search

In this paper, we propose logging and recovery algorithmsfor distributed architectures that use local diskspace to provide transactional facilities locally. Eachnode has its own log file where all log records for updatesto locally cached pages are written. Transactionrollback and node crash recovery are handled exclusivelyby each node and log files are not merged atany time. Our algorithms do not require

Euthimios Panagos; Alexandros Biliris; H. V. Jagadish; Rajeev Rastogi

1996-01-01

168

Log analysis of subsurface geology: Concepts and computer methods  

Microsoft Academic Search

This is a text for engineers\\/graduate students studying petroleum engineering. It provides introduction to log analysis and review of logging tools. It describes common graphical methods of multiple log interpretation, basic concepts of matrix algebra, and examples of statistical analysis and signal processing techniques. It reviews remedial methods directed to the suppression of measurement error associated with logs. The mapping

Doveton

1986-01-01

169

Analysis of open hole logs in the Miocene Stevens Sands  

Microsoft Academic Search

The analysis of open-hole logs in the Stevens Sands is difficult because of the mineralogical composition of the sands and the corresponding effects on the logging tools. Logging parameters presumed in other sandstone reservoirs may not be appropriate to the Stevens and may cause the log analysis to underestimate productive zones. Without the integration of full core data and knowledge

1991-01-01

170

Conserving tigers Panthera tigris in selectively logged Sumatran forests  

Microsoft Academic Search

The response of most large carnivores to selective logging is poorly understood. On the one hand, selective logging may represent loss of important habitat, yet, on the other hand, selective logging may increase browse availability for a terrestrial ungulate prey base, thereby indirectly benefiting large carnivores. Using a camera trap-based sampling method, we estimate tiger density in two primary-selectively logged

Matthew Linkie; Iding Achmad Haidir; Agung Nugroho; Yoan Dinata

2008-01-01

171

There's Life in Those Dead Logs!  

ERIC Educational Resources Information Center

|Although it is unspectacular in appearance, dead wood is one of the most ecologically important resources in forests. Fallen logs, dead standing trees, stumps, and even cavities in live trees fulfill a wide range of roles. Prominent among these is that they provide habitat for many organisms, especially insects. Fourth-grade students at Fox…

Biggs, Devin; Miller, Todd; Hall, Dee

2006-01-01

172

Milankovitch climate cycles in ODP wireline logs  

Microsoft Academic Search

Orbitally induced climatic rhythms can cause cyclical variations in the physical properties or mineralogy of deep-sea sediments. Regional variations in the climatic factors controlling sedimentation (e.g., rainfall, temperature, or current patterns) are likely to cause regional variations in the mineralogic signature of Milankovitch orbital cycles. Downhold geophysical logs, routinely recorded during ODP, continuously sample changes in sediment properties and mineralogy

R. D. Jarrard; X. Golovchenko

1988-01-01

173

Developments in elemental concentration logging and applications  

Microsoft Academic Search

It is noted that the past decade has seen a dramatic growth of gamma-ray spectroscopy logging as a tool for solving geophysical problems. Developments have provided absolute elemental concentrations for a larger set of elements, using elemental analysis (including tracers) for solving many specific oil-field problems and providing a basis, through geochemical research, for developing a wide range of applications

J. S. Schweitzer

1991-01-01

174

Developments In Elemental Concentration Logging And Applications  

Microsoft Academic Search

The past decade has seen a dramatic growth of gamma-ray spectroscopy logging as a tool for solving geophysical problems. Initial attempts generally provided relative elemental concentrations to estimate gross lithological structure, clay volume, and oil saturation. Developments in recent years have provided absolute elemental concentrations for a larger set of elements, using elemental analysis (including tracers) for solving many specific

J. S. Schweitzer

1990-01-01

175

Privacy Protection for Life-log Video  

Microsoft Academic Search

Recent advances in wearable cameras and storage devices allow us to record the holistic human experience for an extended period of time. Such a life-log system can capture audio-visual data anywhere and at any time. It has a wide range of applications from law enforcement, journalism, medicine to personal archival. On the other hand, there is a natural apprehension towards

Jayashri Chaudhari; Sen-ching S. Cheung; M. Vijay Venkatesh

176

Wideband Planar Log-Periodic Antenna  

Microsoft Academic Search

A compact planar wideband microstrip antenna is introduced. The antenna is a log-periodic antenna with 7 dipole elements. The antenna is designed to function in the frequency range of 500 to 700 MHz. It has a dimension of 268 mm by 145 mm by 3 mm. The matching is better than -10 dB in the working bandwidth. The proposed antenna

M. M. Tajdini; M. Shahabadi

2007-01-01

177

Disturbance during Logging Stimulates Regeneration of KOA.  

National Technical Information Service (NTIS)

The abundance and distribution of Acacia koa regeneration after logging were studied on a 500-acre (202-ha) tract of koa forest heavily infested with Passiflora mollissima vines on the island of Hawaii. Koa seedling density was about three times greater i...

P. G. Scowcroft R. E. Nelson

1976-01-01

178

Distortion in resistivity logging at shallow depth  

SciTech Connect

Owing to the proximity of an insulating ground surface, normal resistivity logging at shallow depths (less than 30 m) can yield an apparent resistivity that exceeds 200% of the formation resistivity for a homogeneous medium. The distortion is more acute for long-normal than for short-normal logging. Three examples from a landfill site in southern California are presented to show such distortion. The patterns of distortion are similar for logging devices consisting of either two point-source electrodes or one point-source and one finite length, line-source electrode. The former electrode array is a generally accepted approximation of the latter. However, the simulated apparent resistivity for the line-source array is greater than that for the point-source array at any given depth. A resistivity contrast between the formation and the borehole fluid can shift the magnitude of the background apparent resistivity but does not significantly alter the pattern of distortion. The magnitude of the distortion can be reduced by placing the reference-ground potential electrode at a radial distance that is about equal to the spacing between the downhole upper potential electrode and the upper current electrode. It can also be removed by including the radial distance in an array-dependent geometric factor that accounts for the resistivity of the borehole fluid and the proximity of the logging device to the ground surface.

Lee, T.C. [Univ. of California, Riverside, CA (United States). Dept. of Earth Sciences; Damiata, B.N.

1995-07-01

179

USGS Training on Borehole Geophysical Logging  

USGS Multimedia Gallery

A USGS hydrologist holds an electromagnetic induction borehole logging tool while the tool is calibrated. The hydrologist was participating in a USGS class on how to use electromagnetic induction geophysical methods for groundwater investigations, conducted by the USGS Office of Groundwater Branch o...

2009-05-01

180

Discussion logs for h-childhood  

NSDL National Science Digital Library

This new moderated H-Net discussion list seeks to link international scholars studying the history of childhood and youth in all regions and time periods. Resources available at the site include discussion threads, message logs, a review project, and academic announcements.

181

A First Look at Logging in Gabon  

NSDL National Science Digital Library

This newly released report [.pdf format] from Global Forest Watch (World Resources Institute) takes a first look at Gabon's forestry practices. The report describes how forests are rapidly being conceded to "a handful of logging companies" which export primarily one species of tree to a narrow range of countries.

182

SYNTHETIC ROPE USE IN LOGGING WINCHING APPLICATIONS  

Microsoft Academic Search

The use of ultra high molecular weight polyethylene (UHMWPE) fiber rope as a replacement for steel wire rope shows beneficial properties with the use of synthetic ropes in static line applications such as guylines. The promise shown establishes the basis for expanding its use to running lines for improvements in logging safety, worker ergonomics, and economic efficiency. Research is investigating

Stephen J. Pilkerton; John J. Garland; Jared M. Leonard; John Sessions

183

Logging Truck Noise Near Nesting Northern Goshawks.  

National Technical Information Service (NTIS)

The authors measured noise levels of four logging trucks as the trucks passed within approximately 500 m of two active northern goshawk (Accipiter gentilis) nests on the Kaibab Plateau in northern Arizona in 1997. Neither a brooding adult female nor a lon...

T. G. Grubb L. L. Pater D. K. Delaney

1998-01-01

184

Dual spectra well logging system and method  

Microsoft Academic Search

A well logging system and method are described in which a transmitter in a borehole has at least two radiation detectors sensing either the same condition or two different conditions relating to the earth's formation traversed by the borehole and providing data pulses corresponding in number and peak amplitude to the sensed condition. The transmitter also includes a reference pulse

R. W. Jr. Pitts; H. A. Jr. Whatley

1976-01-01

185

Pressure Instrumentation for Geothermal Borehole Logging.  

National Technical Information Service (NTIS)

Accurate geothermal logging requires pressure measurements with resolutions down to 0.01 psi in environments of up to 275 exp 0 C and 15,000 psi. The characteristics of several basic types of pressure transducers are examined and compared to these require...

T. D. McConnell

1980-01-01

186

Some Limit Theorems in Log Density.  

National Technical Information Service (NTIS)

The purpose of the paper is to study, in a systematic way, 'log' analogues of further classical limit theorems of probability theory. In Section 2 the authors prove a general version of the a.s. central limit theorem and its functional version for indepen...

I. Berkes H. Dehling

1993-01-01

187

The Public Burning Log 1966-77  

Microsoft Academic Search

This is a narrative of the writing and publishing of The Public Burning, taken from logs and letters of the time. Much has been omitted from this sizable chunk of my life that might be of autobiographical curiosity (family, friends, festivities, most reading and travel experiences, writerly and teacherly exchanges, engagement with contemporary art and music, film and photography, and

Robert Coover

2000-01-01

188

Query Logs Alone are not Enough  

Microsoft Academic Search

The practice of guiding a search engine based on query logs observed from the engine's user population provides large volumes of data but potentially also sacrifices the privacy of the user. In this paper, we ask the following question: Is it possible, given rich instrumented data from a panel and usability study data, to observe complete information without routinely analyzing

Carrie Grimes; Diane Tang; Daniel M. Russell

2007-01-01

189

U. S. Gulf Coast field experiences with thin-bed well log analysis  

SciTech Connect

Thinly bedded reservoir sand sequences are encountered throughout the world, and particularly as low-resistivity intervals in the US Gulf Coast area. Despite apparent water saturation values ranging from 55 to 85% based on conventional log interpretation techniques, such intervals can be important producers. However, recent technological advances in novel, high-resolution logging instrumentation, increased high-sample data acquisition advances in high-resolution signal-processing (i.e., deconvolution techniques, and newly developed thin-bed interpretation methods.) An improved reservoir description, such as reliable net pay count enhanced well-to-well correlation, better thin-bed correlation of well log, core, and test data, and thus a more accurate location of oil and gas-bearing stringers and their quantitative evaluation. Several Gulf Coast field examples illustrate these concepts based on well logging, coring, and well test information.

Fertl, W.H. (Atlas Wireline Services, Houston, TX (USA))

1990-09-01

190

Lipophilicity Screening of Novel Drug-like Compounds and Comparison to cLogP  

PubMed Central

We determined the distribution coefficients of solutes between a polymer film phase (polyvinyl chloride (PVC) with 67% (w/w) dioctyl sebacate (DOS)) and an aqueous phase in a 96-well format. The parallel measurement approach is efficient and uses very little material. Polymer-water distribution coefficients (Dpw) at different pH values yield the pKa and polymer-water partition coefficient values (Ppw) of the solutes. Log Ppw of a prominent drug-like compound, 2H-1, 2, 6-thiadiazine, 3-methyl-5-phenyl-, 1, 1-dioxide, is in good agreement with cLogP, while the pKa value is substantially different from calculated values. This method has been also successfully applied to a library of novel drug-like compounds. Log Dpw values (at pH 4.0, 7.0, 10.0) of 24 novel drug-like compounds have been determined with good reproducibility with the 96-well plate approach. Differences between experimental values and a variety of available calculated values are significant. This emphasizes the need for laboratory separations-based measurements of logD.

Lu, Dujuan; Chambers, Peter; Wipf, Peter; Xie, Xiang-Qun; Englert, Danielle; Weber, Stephen

2012-01-01

191

Cryptosporidium Log-inactivation with Ozone Using Effluent CT10, Geometric Mean CT10, Extended Integrated CT10 and Extended CSTR Calculations  

Microsoft Academic Search

The draft Long-Term 2 Enhanced Surface Water Treatment Rule (LT2ESWTR) contains Cryptosporidium log-inactivation CT tables (ozone-in-water concentration [residual], “C” times contact time, T). Depending on water temperature, Cryptosporidium CT values that are listed are 15 to 25 times greater than CT values for equivalent Giardia log-inactivation credit. The elevated operating dose required for Cryptosporidium log-inactivation credit has the potential to

Kerwin L. Rakness; Issam Najm; Mike Elovitz; Dave Rexing; Steve Via

2005-01-01

192

Selecting Aquifer Wells for Planned Gyroscopic Logging  

SciTech Connect

Understanding the configuration of the eastern Snake River Plain aquifer's water table is made difficult, in part, due to borehole deviation in aquifer wells. A borehole has deviation if it is not vertical or straight. Deviation impairs the analysis of water table elevation measurements because it results in measurements that are greater than the true distance from the top of the well to the water table. Conceptual models of the water table configuration are important to environmental management decision-making at the INEEL; these models are based on measurements of depth to the water table taken from aquifer wells at or near the INEEL. When accurate data on the amount of deviation in any given borehole is acquired, then measurements of depth-to-water can be adjusted to reflect the true depth so more accurate conceptual models can be developed. Collection of additional borehole deviation data with gyroscopic logging is planned for selected wells to further our confidence in the quality of water level measurements. Selection of wells for the planned logging is based on qualitative and quantitative screening criteria. An existing data set from magnetic deviation logs was useful in establishing these criteria however, are considered less accurate than gyroscopic deviation logs under certain conditions. Population distributions for 128 aquifer wells with magnetic deviation data were used to establish three quantitative screening thresholds. Qualitative criteria consisted of administrative controls, accessibility issues, and drilling methods. Qualitative criteria eliminated all but 116 of the 337 aquifer wells, in the vicinity of the INEEL, that were initially examined in this screening effort. Of these, 72 have associated magnetic deviation data; 44 do not. Twenty-five (25) of the 72 wells with magnetic deviation data have deviation greater than one of the three quantitative screening thresholds. These 25 are recommended for the planned gyroscopic borehole deviation surveying. Nineteen (19) of the 44 wells without magnetic deviation data were selected for the planned gyroscopic logging based on their location relative to facilities, site boundaries, and contaminant transport concerns. In total, 44 aquifer wells (25 with magnetic deviation data and 19 without) are recommended for planned gyroscopic logging.

Rohe, Michael James; Studley, Gregory Wayne

2002-04-01

193

MieLog: A Highly Interactive Visual Log Browser Using Information Visualization and Statistical Analysis  

Microsoft Academic Search

System administration has become an increasingly important function, with the fundamental task being the inspection of computer log-files. It is not, however, easy to perform such tasks for two reasons. One is the high recognition load of log contents due to the massive amount of textual data. It is a tedious, time-consuming and often error-prone task to read through them.

Tetsuji Takada; Hideki Koike

2002-01-01

194

Downhole logs of natural gamma radiation and magnetic susceptibility and their use in interpreting lithostratigraphy in AND-1B, Antarctica  

NASA Astrophysics Data System (ADS)

The ANDRILL McMurdo Ice Shelf (MIS) project drilled 1285 metres of sediment representing the last 14 million years of glacial history. Downhole geophysical logs were acquired to a depth of 1018 metres, and are complementary to data acquired from the core itself. We describe here the natural gamma radiation (NGR) and magnetic susceptibility logs, and their application to understanding lithological and paleoenvironmental change at ANDRILL McMurdo Ice Shelf Hole AND-1B. Natural gamma radiation logs cover the whole interval from the sea floor to 1018 metres, and magnetic susceptibility and other logs covered the open-hole intervals between 692-1018 and 237-342 metres. NGR logs were stacked and corrected for signal attenuation through the drill pipe, and magnetic susceptibility logs were corrected for drift. In the upper part of AND-1B, clear alternations between low and high NGR values distinguish between diatomite (lacking minerals containing naturally radioactive K, U, and Th) and diamict (containing K-bearing clays, K-feldspar, and heavy minerals). In the lower open-hole logged section, NGR and magnetic susceptibility can also distinguish claystones (rich in K-bearing clay minerals, relatively low in magnetite) and diamicts (relatively high in magnetite), while sandstones generally have high resistivity log values at AND-1B. On the basis of these three downhole logs, three sets of facies can be predicted correctly for 74% of the 692-1018m interval. The logs were then used to predict facies for the 7% of this interval that was unrecovered by coring. Similarly, the NGR log provides the best information on the lithology of the poorly recovered top 25m of AND-1B. Given the understanding of the physical property characteristics of different facies, it is also possible to identify subtle changes in lithology from the physical properties, and help refine parts of the lithostratigraphy (for example, the varying terrigenous content of diatomites).

Williams, T.; Morin, R. H.; Jarrard, R. D.; Jackolski, C. L.; Henrys, S. A.; Niessen, F.; Magens, D.; Kuhn, G.; Monien, D.; Powell, R. D.

2010-12-01

195

Phase transition in a log-normal Markov functional model  

NASA Astrophysics Data System (ADS)

We derive the exact solution of a one-dimensional Markov functional model with log normally distributed interest rates and constant volatility in discrete time. The model is shown to have two distinct limiting states, corresponding to small and asymptotically large volatilities, respectively. These volatility regimes are separated by a phase transition at some critical value of the volatility, at which certain expectation values display nonanalytical behavior as a function of volatility. We investigate the conditions under which this phase transition occurs and show that it is related to the position of the zeros of an appropriately defined generating function in the complex plane, in analogy with the Lee-Yang theory of the phase transitions in condensed matter physics.

Pirjol, Dan

2011-01-01

196

Geothermal logging. Part 1: An introduction to techniques and interpretation  

NASA Astrophysics Data System (ADS)

The purpose of geophysical logging in geothermal investigation is described, and objectives, operations and interpretations in petroleum and geothermal logging are compared. Logging parameters in geothermal investigations are listed and the principles and functions of logging equipment are described. Practical application of well logging in a geothermal drilling operation is emphasized and examples are shown of this application. Various temperature profiles are described, and their interpretation discussed. The information gained by pressure logs is examined and examples of pressure measurement are shown. Lithological logs which incude geological natural gamma ray, gamma-gamma density, neutron-neutron porosity, and resistivity logs are presented. The combined interpretation of lithological logs is igneous rock is discussed.

Stefansson, V.; Steingrimsson, B.

1980-05-01

197

SDSS Log Viewer: visual exploratory analysis of large-volume SQL log data  

NASA Astrophysics Data System (ADS)

User-generated Structured Query Language (SQL) queries are a rich source of information for database analysts, information scientists, and the end users of databases. In this study a group of scientists in astronomy and computer and information scientists work together to analyze a large volume of SQL log data generated by users of the Sloan Digital Sky Survey (SDSS) data archive in order to better understand users' data seeking behavior. While statistical analysis of such logs is useful at aggregated levels, efficiently exploring specific patterns of queries is often a challenging task due to the typically large volume of the data, multivariate features, and data requirements specified in SQL queries. To enable and facilitate effective and efficient exploration of the SDSS log data, we designed an interactive visualization tool, called the SDSS Log Viewer, which integrates time series visualization, text visualization, and dynamic query techniques. We describe two analysis scenarios of visual exploration of SDSS log data, including understanding unusually high daily query traffic and modeling the types of data seeking behaviors of massive query generators. The two scenarios demonstrate that the SDSS Log Viewer provides a novel and potentially valuable approach to support these targeted tasks.

Zhang, Jian; Chen, Chaomei; Vogeley, Michael S.; Pan, Danny; Thakar, Ani; Raddick, Jordan

2012-01-01

198

High resolution gamma spectroscopy well logging system  

SciTech Connect

A Gamma Spectroscopy Logging System (GSLS) has been developed to study sub-surface radionuclide contamination. The absolute counting efficiencies of the GSLS detectors were determined using cylindrical reference sources. More complex borehole geometries were modeled using commercially available shielding software and correction factors were developed based on relative gamma-ray fluence rates. Examination of varying porosity and moisture content showed that as porosity increases, and as the formation saturation ratio decreases, relative gamma-ray fluence rates increase linearly for all energies. Correction factors for iron and water cylindrical shields were found to agree well with correction factors determined during previous studies allowing for the development of correction factors for type-304 stainless steel and low-carbon steel casings. Regression analyses of correction factor data produced equations for determining correction factors applicable to spectral gamma-ray well logs acquired under non-standard borehole conditions.

Giles, J.R.; Dooley, K.J.

1997-05-01

199

Quantifying logging residue - before the fact  

SciTech Connect

Tree biomass estimation, which is being integrated into the U.S. Forest Service Renewable Resources Evaluation Program, will give foresters the ability to estimate the amount of logging residues they might expect from harvested treetops and branches and residual rough, rotten, and small trees before the actual harvest. With planning, and increased demand for such timber products as pulpwood and fuelwood, product recovery could be increased by up to 43 percent in softwood stands and 99% in hardwoods. Recovery levels affect gross product receipts and site preparation costs. An example of product recovery and residue generation is presented for three harvesting options in Pennsylvania hardwood stands. Under the whole-tree harvesting option, 46% more product was recovered than in single product harvesting, and logging residue levels were reduced by 58%.

Bones, J.T.

1982-06-01

200

The Nevada Test Site neutron log calibrator  

SciTech Connect

A new calibrator for neutron logs in large-diameter holes has been built at the Nevada Test Site. It consists of two cylinders, each made of six wedge-shaped cells. The outside diameter of each cylinder is 4.8 m, and the inside diameter is 2.4 m; the height is 2.3 m. The cells were filled with mixtures of hydrated alumina, tabular alumina, sand, and water to achieve a large range of bulk density and hydrogen index. A new calibration algorithm, using three-dimensional interpolation in hydrogen index-gap-density space has been developed to determine hydrogen index from log data. There is evidence that the new algorithm is slightly more accurate than the previous algorithm.

Hearst, J.R.

1994-02-01

201

THE GIANT SUKHOI LOG GOLD DEPOSIT. SIBERIA  

Microsoft Academic Search

The Sukhoi Log gold deposit is cenhally located in the L,€na goldfield region, approximately 850 lcn IrlE fmm the city of Irkutsk, aad is hoshd in Upper Proterozoic marine sandstone, carbonaceous slate and phyuita, metemorphos€d to low greensddst faci€s in an ouflying part of the major Akitkan Foldbelt. Ihe disseminated pyritic tabular orebody has no outcrop, is defined solely by

B. L. Woodl; Moscow N. L

202

Using Web Logs in the Science Classroom  

ERIC Educational Resources Information Center

|As educators we must ask ourselves if we are meeting the needs of today's students. The science world is adapting to our ever-changing society; are the methodology and philosophy of our educational system keeping up? In this article, you'll learn why web logs (also called blogs) are an important Web 2.0 tool in your science classroom and how they…

Duplichan, Staycle C.

2009-01-01

203

Optical communication system for drill hole logging  

SciTech Connect

An optical communication system for drill hole logging comprises an armored cable containing one or more glass clad optical fibers inside a tubular moisture barrier, a neodymium laser in the cable reel radiates infrared light into one of the fibers, a modulator in the downhole cable-head connector shell modulates light and returns it to the surface, and a semiconductor detector in the reel demodulates the data signal from the returning light.

Gould, G.

1985-10-15

204

Data transmission system for logging tools  

SciTech Connect

A system for storing and transmitting pulse count information is disclosed wherein electrical pulses produced by logging tools, such as thermal neutron, are counted and stored downhole to remove the effect of lengthly transmission lines. In a further embodiment a coded multiplexed signal is transmitted uphole indicating the tool from which the transmitted data was received and the total count for a predetermined time period.

Sidhwa, F. J.

1985-03-19

205

Subsurface sequence stratigraphic correlation using well logs  

NSDL National Science Digital Library

Students are given hard copies of a subsurface section containing gamma and resistivity logs of nine closely-spaced (well distance varies from 1 to 3 km) wells from Delaware Basin, southeast New Mexico for an interval of ~ 200 m clastic succession of Morrow sandstone of Pennsylvanian age. Core sedimentology of one of these wells is also provided. Students' task is to correlate the well logs to generate a stratigraphic cross-section of the area using sequence stratigraphic approach. As the data are from Delaware Basin, southeast New Mexico, student should first gather the knowledge of regional setting of the basin, with a particular emphasis to the paleo-eustasy. (Clue: in Delaware Basin, Morrow sandstones deposited in a low accommodation settings with high-amplitude fluctuations of sea-level.) When correlating the well logs students should start with the well which has lithological information. Students should try to correlate the mudstones first. The two most prominent sequence stratigraphic surfaces with comparatively higher correlation-length are 'sequence boundary' produced by pronounced fall of sea-level, and 'maximum flooding surface' generated at the time of highest stand of sea-level. Students should pay particular attention to incised-valley-fill deposits. After completing the correlation, students should check whether their correlation satisfy our prevailing ideas of sequence stratigraphy and stratal packaging. Student should prepare a brief description of overall depositional environments and sea-level history of the area substantiating their subsurface correlation. By doing this exercise, students will learn how to apply sequence stratigraphic principles in interpreting subsurface data, particularly from well logs.

Gani, M. R.

206

Protocol Discovery from Imperfect Service Interaction Logs  

Microsoft Academic Search

This paper deals with the problem of discovering protocol models by analyzing real-world interaction logs. There are several scenarios where protocol discovery is useful and needed: (i) In practice, the protocol definition may not be available. This can happen for many reasons, e.g., the service has been developed using a bottom-up approach, by simply SOAP-ifying an existing application; (ii) even

Hamid R. Motahari Nezhad; Régis Saint-paul; Boualem Benatallah; Fabio Casati

2007-01-01

207

Flow logging applied in fractured rocks  

NASA Astrophysics Data System (ADS)

Fractured zones are usually identified by the basic logging methods but the volume of permeable fractures intersecting boreholes is often too small for their identification. Fluid logging measurements can help to localize natural flow and determine hydraulic properties of fractures during the pumping. Borehole flowmeter measurements or fluid logging measurements are conventional methods used for the determination of quantitative parameters of the flowing fluid in boreholes with the goal to estimate hydraulic conductivity of aquifers. With the increasing interest in the research of fractured formations and their hydraulic properties, new field techniques based on the repeated measurement of the vertical velocity in an observation borehole during the short hydraulic test (hydraulic pulse) in an other borehole of the tested locality have been elaborated. There is a tendency to increase the lateral range of investigation, it means to make the cross-hole tests in boreholes with greater distance. Such cross-hole tests need to make the measurement of the induced vertical flow in the observation borehole with high resolution flowmeters able to measure vertical flow velocities in the range 10-4 m/s and the flow rates in the range 10-6 m3/s. The new photometric flowmeter was developed for this purpose. The results of the photometric flowmeter measurements were compared with the fluid logging measurements and with heat-pulse flowmeter measurements. In our contribution examples of the comparison of measurements mentioned above in two boreholes situated in granite massif in the Czech Republic are demonstrated. Boreholes were drilled in the program of Czech state institution SÚRAO (Radioactive Waste Repository Authority). The research project is financially supported by the Grant Agency of the Czech Republic under the No. 208/07/0777.

Urík, J.; Lukeš, J.; Kobr, M.; Mareš, S.; Williams, J. H.

2009-04-01

208

Analysis of log-periodic vibrator antennas  

Microsoft Academic Search

The theory of periodic structures is used to study the radiation mechanism of log-periodic vibrator antennas (LPVAs) and phased arrays based on them. It is shown that the phase shift between currents on adjacent vibrators in the radiating region is close to 1.5pi. The stability of the LPVA characteristics with respect to mutual couplings when the antenna is used as

V. A. Iatskevich

1983-01-01

209

Derive capillary pressure from well logs  

SciTech Connect

A new approach has been developed to estimate in-situ capillary pressure and relative permeability characteristics in the transition zone. The technique is based on incorporating petrophysical data measured on core samples with well log analysis. Relative permeability can be determined for both drainage and inhibition conditions using the matched capillary pressure data. A technique has been developed to extrapolate petro-physical data where core data is absent or not representative of in-situ conditions. It is based on using log data to derive a water saturation vs. depth profile in the transition zone of the formation of interest. The log-derived water saturation distribution is then correlated to generalized capillary pressure curves typical of the formation studied. The capillary pressure type curves are generated from available core data and other petrophysical information. Relative permeability curves are then generated using correlations based on Purcell's model. The technique can be used in multi-layered and homogeneous reservoirs provided that one homogeneous layer is at least 20 ft thick.

Ibrahim, A. (Suez Canal Univ. (Egypt)); Desbrandes, R.; Bassiouni, Z. (Louisiana State Univ., Baton Rouge, LA (United States))

1994-07-01

210

Precision pressure/temperature logging tool  

SciTech Connect

Past memory logging tools have provided excellent pressure/temperature data when used in a geothermal environment, and they are easier to maintain and deploy than tools requiring an electric wireline connection to the surface. However, they are deficient since the tool operator is unaware of downhole conditions that could require changes in the logging program. Tools that make ``decisions`` based on preprogrammed scenarios can partially overcome this difficulty, and a suite of such memory tools has been developed at Sandia National Laboratories. The first tool, which forms the basis for future instruments, measures pressure and temperature. Design considerations include a minimization of cost while insuring quality data, size compatibility with diamond-cored holes, operation in holes to 425 C (800 F), transportability by ordinary passenger air service, and ease of operation. This report documents the development and construction of the pressure/temperature tool. It includes: (1) description of the major components; (2) calibration; (3) typical logging scenario; (4) tool data examples; and (5) conclusions. The mechanical and electrical drawings, along with the tool`s software, will be furnished upon request.

Henfling, J.A.; Normann, R.A.

1998-01-01

211

Contribution of logging data to sedimentology and stratigraphy. [Electrofacies  

SciTech Connect

A technique has been developed using multivariate analysis of logging data to give a high-resolution sedimentological description of any sequence of formations. The number of different logs and their range allow determination of many of the physical characteristics of the rock. The definition of a lithofacies has been extended by introducing the concept of an electrofacies, constructed on the basis of all the logging data at any depth interval. Each logging datum is considered a descriptor for purposes of establishing electrofacies in a logged interval. Once established, electrofacies then can be correlated with actual geologic facies, if the logged interval has been cored. 23 refs.

Serra, O.; Abbott, H.T.

1982-02-01

212

Wireline log modeling of geologic data: application to automated lithology identification  

SciTech Connect

A method has been developed to quantitatively translate geologic data into modeled wireline log data. The modeled log data have been used to construct a data base for a computer program that performs automatic lithology identification. This technique provides accuracy previously unattainable using empirically constructed data bases. Electrofacies - n-dimensional ellipsoids defined by the n log measurements of each rock model - are constructed from the synthetic data and entered in the data base. The electrofacies are defined by minimum and maximum log values for the eight possible log measurements (density, neutron porosity, gamma ray, sonic transit time, photoelectric cross section, potassium, thorium, and uranium) and correlation coefficients for each possible pair of logs. A data base containing approximately 130 electrofacies has been constructed for the Permian basin region of west Texas and has been tested on a variety of lithologies. Comparison of results using the modeled data base and sidewall core analyses demonstrates the accuracy of the data base for automatic lithology identification.

King, D.E.; Quirein, J.A.

1986-05-01

213

Quality of the log-geometric distribution extrapolation for smaller undiscovered oil and gas pool size  

USGS Publications Warehouse

The U.S. Geological Survey procedure for the estimation of the general form of the parent distribution requires that the parameters of the log-geometric distribution be calculated and analyzed for the sensitivity of these parameters to different conditions. In this study, we derive the shape factor of a log-geometric distribution from the ratio of frequencies between adjacent bins. The shape factor has a log straight-line relationship with the ratio of frequencies. Additionally, the calculation equations of a ratio of the mean size to the lower size-class boundary are deduced. For a specific log-geometric distribution, we find that the ratio of the mean size to the lower size-class boundary is the same. We apply our analysis to simulations based on oil and gas pool distributions from four petroleum systems of Alberta, Canada and four generated distributions. Each petroleum system in Alberta has a different shape factor. Generally, the shape factors in the four petroleum systems stabilize with the increase of discovered pool numbers. For a log-geometric distribution, the shape factor becomes stable when discovered pool numbers exceed 50 and the shape factor is influenced by the exploration efficiency when the exploration efficiency is less than 1. The simulation results show that calculated shape factors increase with those of the parent distributions, and undiscovered oil and gas resources estimated through the log-geometric distribution extrapolation are smaller than the actual values. ?? 2010 International Association for Mathematical Geology.

Chenglin, L.; Charpentier, R. R.

2010-01-01

214

Computation of porosity and water content from geophysical logs, Yucca Mountain, Nevada  

SciTech Connect

Neutron and density logs acquired in boreholes at Yucca Mountain, Nevada are used to determine porosity and water content as a function of depth. Computation of porosity requires an estimate of grain density, which is provided by core data, mineralogical data, or is inferred from rock type where neither core nor mineralogy are available. The porosity estimate is merged with mineralogical data acquired by X-ray diffraction to compute the volumetric fractions of major mineral groups. The resulting depth-based portrayal of bulk rock composition is equivalent to a whole rock analysis of mineralogy and porosity. Water content is computed from epithermal and thermal neutron logs. In the unsaturated zone, the density log is required along with a neutron log. Water content can also be computed from dielectric logs, which were acquired in only a fraction of the boreholes, whereas neutron logs were acquired in all boreholes. Mineralogical data are used to compute a structural (or bound) water estimate, which is subtracted from the total water estimate from the neutron-density combination. Structural water can be subtracted only from intervals where mineralogical analyses are available; otherwise only total water can be reported. The algorithms and procedures are applied to logs acquired during 1979 to 1984 at Yucca Mountain. Examples illustrate the results. Comparison between computed porosity and core measurements shows systematic differences ranging from 0.005 to 0.04. These values are consistent with a sensitivity analysis using uncertainty parameters for good logging conditions. Water content from core measurements is available in only one borehole, yielding a difference between computed and core-based water content of 0.006.

Nelson, P.H.

1996-12-31

215

Gallipolis Locks and Dam Ohio River Basin Mason County, West Virginia. Foundation Report. Volume 3. Core Logs Construction of Two Parallel Locks and Canal.  

National Technical Information Service (NTIS)

CONTENTS: Outlet Structure Core Logs; River Inlet Core Logs; Land Culvert Core Logs; Middle Culvert Core Logs; River Culvert Core Logs; Downstream Approach wall Core Logs; Upstream Approach Wall Core Logs; River wall Core Logs; Middle Wall Core Logs; Land...

1993-01-01

216

3. MAIN ELEVATION, DETAIL SHOWING HEWN LOGS WITH HALFDOVETAIL JOINTS; ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. MAIN ELEVATION, DETAIL SHOWING HEWN LOGS WITH HALF-DOVETAIL JOINTS; LATHE AND PLASTER ADDITION; AND CLAPBOARD SIDING - Shinn-Curtis Log Cabin, 23 Washington Street (moved from Rancocas Boulevard), Mount Holly, Burlington County, NJ

217

Well-Logging Techniques for Mineral Deposit Evaluation: A Review.  

National Technical Information Service (NTIS)

Well-logging techniques that have been used to evaluate various types of mineral deposits are discussed briefly, and many pertinent references are cited. Information is categorized by mineral commodity to make it easy to determine what logging techniques ...

J. H. Scott B. L. Tibbetts

1974-01-01

218

Practical methods for the measurement of logP for surfactants.  

PubMed

Hydrophobicity is a commonly used parameter in quantitative structure activity relationships. The ability to determine the octanol-water partition coefficient (logP) empirically for non-ionizing, non-surfactant type chemicals using traditional stir-flask methods has been successful and well documented. In comparison the ability to measure logP for surfactants is considered impractical due to their amphiphilic nature, which gives them a tendency to form micelles and reside at the octanol-water interface. In this study we have shown that working with compounds below their critical micelle concentrations (CMC), at the experimental concentrations, it is possible to obtain experimental logP values for a series of sulphobetaines using the stir-flask method coupled with reversed phase-high performance liquid chromatography (RP-HPLC). Until now the ability to verify calculated logP values for surfactants has been limited. Measuring logP as described here can now be applied to other surfactants to validate existing and new modifications to the fragment method. PMID:20394985

Short, J; Roberts, J; Roberts, D W; Hodges, G; Gutsell, S; Ward, R S

2010-04-14

219

Theoretical studies of permeability inversion from seismoelectric logs  

NASA Astrophysics Data System (ADS)

Permeability is one of the most important parameters for evaluating the level of difficulty in oil and gas exploitation. A quick, continuous and accurate in-situ estimate of reservoir permeability is highly significant. Stoneley wave logs have been used to determine formation permeability (Tang and Cheng, 1996). However, the inversion errors of this method are too big in low-permeability formations, especially in high-porosity and low-permeability formations resulting from the high clay content in pores. In this study, we propose to invert permeability by using the full waveforms of seismoelectric logs with low frequencies. This method is based on the relationship of permeability with the ratio of the electric excitation intensity to the pressure field's (REP) with respect to the Stoneley wave in seismoelectric logs. By solving the governing equations for electrokinetic coupled wavefields in homogeneous fluid-saturated porous media (Pride, 1994), we calculate the full waveforms of the borehole seismoelectric wavefields excited by a point pressure source and investigate frequency-dependent excitation intensities of the mode waves and excitation intensities of the real branch points in seismoelectric logs. It is found that the REP's phase, which reflects the phase discrepancy between the Stoneley-wave-induced electric field and the acoustic pressure, is sensitive to formation permeability. To check the relation between permeability and REP's phase qualitatively, an approximate expression of the tangent of the REP's argument is derived theoretically as tan(?EP) ?-?c/? = -??/ (2?f? ??f?0), where ?EPdenotes the arguments of the REP and their principal value is the REP's phase,? is the angular frequency,?c is a critical angular frequency that separates the low-frequency viscous flow from the high-frequency inertial flow, ? is the porosity, ?? is the tortuosity, ?0 is the Darcy permeability, ?f and ? are the density and the viscosity of the pore fluid, f is the frequency. According to this approximate expression, if porosity, tortuosity and pore fluid properties (density and viscosity) have been measured by some methods or estimated by empirical formulas, permeability can be inverted by calculating tan(?EP) and using its corresponding frequency. To test this method, permeabilities of different sandstones are inverted from the synthetic full-waveform data of the seismoelectric logs. A modified inversion process is proposed based on the analysis of the inversion errors, by which the relative errors are controlled below 25% and they are smaller than those of the permeability inversion from the Stoneley wave logs. This study is supported by National Natural Science Foundations of China (41174110), Natural Science Foundation of Heilongjiang Province of China (QC2010025), Research Fund for the Doctoral Program of Higher Education of China (20102302120024), Postdoctoral Science Foundation of China (2011M500651).

Hu, H.; Guan, W.; Zhao, W.

2012-04-01

220

Minimizing Bandwidth for Remote Access to Cryptographically Protected Audit Logs  

Microsoft Academic Search

Tamperproof audit logs are an essential tool for computer forensics. Building on the work in (SK98,SK99), we show how to build a tamperproof audit log where the amount of information exchange re- quired to verify the entries in the audit log is greatly reduced. By making audit-log verification more efficient, this system is more suitable for im- plementation in low-bandwidth

John Kelsey; Bruce Schneier

1999-01-01

221

Outcrop gamma-ray logging applied to subsurface petroleum geology  

SciTech Connect

Developing a gamma-ray log profile of an outcrop with a hand-held scintillometer has many applications to subsurface petroleum geology. The outcrop gamma-ray log provides a readily understandable bridge between what is observed in outcrop and what is to be interpreted on well logs and seismic records. Several examples are presented in this paper that demonstrate major applications. An outcrop from the Cretaceous Mesaverde Group in Colorado provides an excellent example of the use of outcrop gamma-ray logs to better visualize spatial variability of depositional settings for improved well log correlations. Out crops from the Cretaceous Almond Formation, Niobrara Formation, and Graneros Shale in Colorado serve as examples of outcrop gamma-ray logging used to correlate outcrops with their subsurface equivalents for improved lithologic and stratigraphic interpretation of well logs. Outcrops of the Cretaceous Sharon Springs Member of the Pierre Shale in Colorado and the Eocene Green River Formation in Wyoming provide examples of the application of outcrop-gamma ray logging to identify and characterize organic-rich shales in outcrops and on well logs. Outcrops of the Pennsylvanian Jackfork Formation in Arkansas demonstrate the use of outcrop logging to yield improved interpretation of reservoir quality on well logs and for one- and two-dimensional seismic modeling. An outcrop of Precambrian and Cambro-Ordovician rocks from Algeria provides an example of outcrop logging to recognize unconformities and other major surfaces on well logs. An outcrop of the Niobrara Formation in Colorado is used as an example for improved understanding of horizontal gamma-ray log response. The example logs presented are all drived with a hand-held scintillometer. This technique is simple, quick, and relatively inexpensive, so is recommended for any outcrop work that is intended to be applied t;o subsurface well logs or seismic interpretation.

Slatt, R.M.; Borer, J.M.; Horn, B.W. [Colorado School of Mines, Golden, CO (United States)] [and others

1995-10-01

222

40 CFR 90.412 - Data logging.  

Code of Federal Regulations, 2010 CFR

...one Hz (one time per second). (d) Determine the final value for power by averaging the individually calculated power points for each value of speed and torque recorded during the sampling period. As an alternative, the final value for...

2010-07-01

223

40 CFR 90.412 - Data logging.  

Code of Federal Regulations, 2010 CFR

...one Hz (one time per second). (d) Determine the final value for power by averaging the individually calculated power points for each value of speed and torque recorded during the sampling period. As an alternative, the final value for...

2009-07-01

224

Entropy of search logs: how hard is search? with personalization? with backoff?  

Microsoft Academic Search

How many pages are there on the Web? 5B? 20B? More? Less? Big bets on clusters in the clouds could be wiped out if a small cache of a few million urls could capture much of the value. Language modeling techniques are applied to MSN's search logs to estimate entropy. The perplexity is surprisingly small: millions, not billions. Entropy is

Qiaozhu Mei; Kenneth Ward Church

2008-01-01

225

Marine log transportation and handling systems in british columbia: Impacts on coastal management  

Microsoft Academic Search

Over 90 percent of British Columbia's annual log harvest enters into complex water?based systems of transportation, storage, and handling. These systems have considerable impacts on a wide range of coastal resources and uses. A number of site?specific conflicts have arisen between forestry and preexisting or emerging values including fisheries, mariculture, recreational boating, and harbor redevelopment. Specific data on the impacts

Michael C. R. Edgell; William M. Ross

1983-01-01

226

Inference for Log-Gamma Distribution Based on Progressively Type-II Censored Data  

Microsoft Academic Search

We discuss the maximum likelihood estimates (MLEs) of the parameters of the log-gamma distribution based on progressively Type-II censored samples. We use the profile likelihood approach to tackle the problem of the estimation of the shape parameter ?. We derive approximate maximum likelihood estimators of the parameters ? and ? and use them as initial values in the determination of

Chien-Tai Lin; Sam J. S. Wu; N. Balakrishnan

2006-01-01

227

Comparing Two Samples: Extensions of the t, Rank-Sum, and Log-Rank Tests  

Microsoft Academic Search

I consider the problem of testing that two populations are identical with respect to the distribution of a continuous variable against the alternative that values tend to be larger in one population. I observe that the t, rank-sum, and log-rank tests are insensitive for a large class of alternatives that may be expected to occur commonly in practice, propose a

Peter C. Obrien

1988-01-01

228

Geochemical Mud Logging of geothermal drilling  

SciTech Connect

The experience and results described in the present paper were developed over nearly two decades, with a major R&D project around 1980. The expression Geochemical Mud Logging (GML) has ill defined meaning in the geothermal industry, and ought to be specified. We refer here to GML as featuring mud and formation fluid tracer(s) and temperature as the bare essentials and with specified accuracies. Air and water logging are expected to be less demanding with regard to analysis accuracy, but are not discussed in this report. During application of GML to several drill holes with low formation permeabilities and under conditions of high temperature and high mud weight, GML as specified, revealed unexpected influx of formation brine. Such influx was a recurring feature that has been referenced to individual fractures and reflects both fracture size and permeability. As a consequence, continuous or subcontinuous sampling of mud systems appears more cost effective than trying to keep up with cumulative changes of bulk mud composition; although, the latter approach is more sensitive to extremely low rate, steady, inflow of formation fluid into the mud system. It appears, that based on this influx of formation fluid, permeability can be estimated well before mud losses are detected and/or drill strings are stuck. The main advantages of GML are: (1) the capability to assess formation temperature and permeability in nearly real time, resulting in (a) assessments of undisturbed formation and (b) having data in hand for holes lost during drilling operations and (2) being effective under conditions of very high temperatures where electrical logs are very costly and less reliable. Estimated cost for GML is $1500 per day (1982) based on assessments of R&D operations. However, extrapolating to larger scale services and to different operating conditions is indeed difficult. GML cost is probably the only significant point of controversy with regard to GML being a viable evaluation tool.

Tonani, F.B.; Guidi, M.; Johnson, S.D.

1988-01-01

229

Well log evaluation of natural gas hydrates  

SciTech Connect

Gas hydrates are crystalline substances composed of water and gas, in which a solid-water-lattice accommodates gas molecules in a cage-like structure. Gas hydrates are globally widespread in permafrost regions and beneath the sea in sediment of outer continental margins. While methane, propane, and other gases can be included in the clathrate structure, methane hydrates appear to be the most common in nature. The amount of methane sequestered in gas hydrates is probably enormous, but estimates are speculative and range over three orders of magnitude from about 100,000 to 270,000,000 trillion cubic feet. The amount of gas in the hydrate reservoirs of the world greedy exceeds the volume of known conventional gas reserves. Gas hydrates also represent a significant drilling and production hazard. A fundamental question linking gas hydrate resource and hazard issues is: What is the volume of gas hydrates and included gas within a given gas hydrate occurrence? Most published gas hydrate resource estimates have, of necessity, been made by broad extrapolation of only general knowledge of local geologic conditions. Gas volumes that may be attributed to gas hydrates are dependent on a number of reservoir parameters, including the areal extent ofthe gas-hydrate occurrence, reservoir thickness, hydrate number, reservoir porosity, and the degree of gas-hydrate saturation. Two of the most difficult reservoir parameters to determine are porosity and degreeof gas hydrate saturation. Well logs often serve as a source of porosity and hydrocarbon saturation data; however, well-log calculations within gas-hydrate-bearing intervals are subject to error. The primary reason for this difficulty is the lack of quantitative laboratory and field studies. The primary purpose of this paper is to review the response of well logs to the presence of gas hydrates.

Collett, T.S.

1992-10-01

230

Well log evaluation of natural gas hydrates  

SciTech Connect

Gas hydrates are crystalline substances composed of water and gas, in which a solid-water-lattice accommodates gas molecules in a cage-like structure. Gas hydrates are globally widespread in permafrost regions and beneath the sea in sediment of outer continental margins. While methane, propane, and other gases can be included in the clathrate structure, methane hydrates appear to be the most common in nature. The amount of methane sequestered in gas hydrates is probably enormous, but estimates are speculative and range over three orders of magnitude from about 100,000 to 270,000,000 trillion cubic feet. The amount of gas in the hydrate reservoirs of the world greedy exceeds the volume of known conventional gas reserves. Gas hydrates also represent a significant drilling and production hazard. A fundamental question linking gas hydrate resource and hazard issues is: What is the volume of gas hydrates and included gas within a given gas hydrate occurrence Most published gas hydrate resource estimates have, of necessity, been made by broad extrapolation of only general knowledge of local geologic conditions. Gas volumes that may be attributed to gas hydrates are dependent on a number of reservoir parameters, including the areal extent ofthe gas-hydrate occurrence, reservoir thickness, hydrate number, reservoir porosity, and the degree of gas-hydrate saturation. Two of the most difficult reservoir parameters to determine are porosity and degreeof gas hydrate saturation. Well logs often serve as a source of porosity and hydrocarbon saturation data; however, well-log calculations within gas-hydrate-bearing intervals are subject to error. The primary reason for this difficulty is the lack of quantitative laboratory and field studies. The primary purpose of this paper is to review the response of well logs to the presence of gas hydrates.

Collett, T.S.

1992-10-01

231

Learning Logs in the Science Classroom: The Literacy Advantage  

ERIC Educational Resources Information Center

|In this article, the author discusses one of the most functional forms of writing to learn, the two-column learning logs. Two-column learning logs are based on the premise that collecting information and processing information are two very different aspects of learning. Two-column logs allow students to connect the facts and theories of science…

Steenson, Cheryl

2006-01-01

232

Methods of interpreting wireline logs in an igneous reservoir  

Microsoft Academic Search

New interpretation methods were derived for log evaluation in a reservoir composed of igneous rock. The hydrocarbon reservoir studied was the fractured igneous basement rocks that produce in the Panhandle field in Texas. The need to locate concentrations of natural fractures, recognize petrographic differences, and possibly determine fracture mineralogy created the need for improved interpretation of existing standard logs. Logs

B. A. Weimer; M. S. Manwaring

1987-01-01

233

Geophysical borehole logging in the unsaturated zone, Yucca Mountain, Nevada  

Microsoft Academic Search

Borehole geophysical logging for site characterization in the volcanic rocks at the proposed nuclear waste repository at Yucca Mountain, Nevada, requires data collection under rather unusual conditions. Logging tools must operate in rugose, dry holes above the water table in the unsaturated zone. Not all logging tools will operate in this environment, therefore; careful consideration must be given to selection

U. Schimschal; P. H. Nelson

1991-01-01

234

Geochemical Logging of a Middle East Carbonate Reservoir  

Microsoft Academic Search

This paper reports on geochemical logs which when run through a complex carbonate formation yield accurate elemental concentration logs. These are instrumental to the computation of detailed formation mineralogy and derivative properties, such as matrix density and sigma. The quantitative mineralogy logs also are used to estimate permeability empirically with a correlation observed from core data.

Susan Herron; Mario Petricola; Roy Dove

1992-01-01

235

Tree Species Diversity in Commercially Logged Bornean Rainforest  

Microsoft Academic Search

The effects of commercial logging on tree diversity in tropical rainforest are largely unknown. In this study, selectively logged tropical rainforest in Indo- nesian Borneo is shown to contain high tree species richness, despite severe structural damage. Plots logged 8 years before sampling contained fewer spe- cies of trees greater than 20 centimeters in diameter than did similar-sized unlogged plots.

Charles H. Cannon; David R. Peart; Mark Leighton

1998-01-01

236

Geochemical logging of a middle east carbonate reservoir  

SciTech Connect

This paper reports on geochemical logs which when run through a complex carbonate formation yield accurate elemental concentration logs. These are instrumental to the computation of detailed formation mineralogy and derivative properties, such as matrix density and sigma. The quantitative mineralogy logs also are used to estimate permeability empirically with a correlation observed from core data.

Herron, S.L.; Dove, R.E. (Schlumberger-Doll Research Center, Ridgefield, CT (United States)); Petricola, M. (Schlumberger Well Services, Houston, TX (United States))

1992-11-01

237

EFFECTS OF LOG HANDLING AND STORAGE ON WATER QUALITY  

EPA Science Inventory

The biological and chemical effects of three types of log storage on water quality were investigated. Three flow-through log ponds, two wet deck operations, and five log rafting areas were studied. Both biological and chemical aspects of stream quality can be adversely affected b...

238

Interactive, Collaborative, Electronic Learning Logs in the Physics Classroom  

Microsoft Academic Search

I describe my experiences using Hickman's Interactive Collaborative Electronic Learning Logs teaching HS Physics. ICE Learning Logs are written in student groups to answer questions posed by the instructor, who then in turn responds to each group's entry before the next class. These logs were used with non-physics majors in both algebra and calculus-based introductory physics courses, and also at

Chris Gosling

2006-01-01

239

Mining On-line Newspaper Web Access Logs  

Microsoft Academic Search

With the explosive growth of data available on the Internet, discovery and analysis of useful information from web log data becomes a practical necessity. However, analysis of large web log files is a complex task not fully addressed by existing web access analyzers. Using commercial software, we applied data mining technology to analyze access log records collected on a web

Paulo Batista; Mário J. Silva

2002-01-01

240

Log-normal distribution of electromigration lifetimes  

SciTech Connect

It has been shown that a normal temperature distribution within a sample set can produce a log-normal failure rate in electromigration experiments if it is assumed that the equation t/sub f/=Aj/sup -n/ exp(E/sub f//kT) holds for individual stripe lifetimes. It has also been pointed out that if sigma's determined under accelerated-stress conditions are used to predict failure under normal-use conditions, incorrect failure rates may result. It has also been demonstrated that most of the sigma's observed in accelerated tests can be attributed to variations in temperature.

Lloyd, J.R.

1979-07-01

241

Nonlinear filters with log-homotopy  

NASA Astrophysics Data System (ADS)

We derive and test a new nonlinear filter that implements Bayes' rule using an ODE rather than with a pointwise multiplication of two functions. This avoids one of the fundamental and well known problems in particle filters, namely "particle collapse" as a result of Bayes' rule. We use a log-homotopy to construct this ODE. Our new algorithm is vastly superior to the classic particle filter, and we do not use any proposal density supplied by an EKF or UKF or other outside source. This paper was written for normal engineers, who do not have homotopy for breakfast.

Daum, Fred; Huang, Jim

2007-08-01

242

Place Value  

NSDL National Science Digital Library

Practice place value! Fight the pirates in Pirates Place Value Uncover the hidden picture in Place value hidden picture Take the quiz at place value quiz Keep practicing with Place value to 1000 Stretch your brain with Place value to 100,000 ...

Peake, Mrs.

2011-08-18

243

Optimum parameters in a model for tumour control probability, including interpatient heterogeneity: evaluation of the log-normal distribution  

NASA Astrophysics Data System (ADS)

The heterogeneity of human tumour radiation response is well known. Researchers have used the normal distribution to describe interpatient tumour radiosensitivity. However, many natural phenomena show a log-normal distribution. Log-normal distributions are common when mean values are low, variances are large and values cannot be negative. These conditions apply to radiosensitivity. The aim of this work was to evaluate the log-normal distribution to predict clinical tumour control probability (TCP) data and to compare the results with the homogeneous (?-function with single ?-value) and normal distributions. The clinically derived TCP data for four tumour types—melanoma, breast, squamous cell carcinoma and nodes—were used to fit the TCP models. Three forms of interpatient tumour radiosensitivity were considered: the log-normal, normal and ?-function. The free parameters in the models were the radiosensitivity mean, standard deviation and clonogenic cell density. The evaluation metric was the deviance of the maximum likelihood estimation of the fit of the TCP calculated using the predicted parameters to the clinical data. We conclude that (1) the log-normal and normal distributions of interpatient tumour radiosensitivity heterogeneity more closely describe clinical TCP data than a single radiosensitivity value and (2) the log-normal distribution has some theoretical and practical advantages over the normal distribution. Further work is needed to test these models on higher quality clinical outcome datasets.

Keall, P. J.; Webb, S.

2007-01-01

244

AVO and anisotropy from logs and walkaways  

SciTech Connect

AVO (amplitude versus offset) is the seismic technique used for mapping lithology, and modeling is an important step for successful AVO interpretations. Shear velocity measurements are essential, since AVO attempts to exploit the elastic (as opposed to acoustic) nature of seismic wave propagation. A property of seismic wave propagation not often considered is anisotropy. This is probably because the magnitude of the anisotropy has been difficult to measure, and its effect on AVO is not widely known. New technology is helping to improve AVO modeling. Dipole source shear logging tools can now measure very slow shear velocities, increasing the range of applicability of AVO, and new borehole seismic techniques can measure anisotropy. When integrated, these new measurements provide more detailed information about the elastic moduli that govern wave propagation, and bring the possibility for greater reliability in AVO interpretation. Two examples of ray-trace AVO synthetics are shown to illustrate typical AVO responses and the importance of shear velocity information. An overview of anisotropy is given and a new technique to estimate anisotropy from walkaway surveys (multi-offset VSPs) is described. The log and walkaway measurements are then integrated to study the impact of anisotropy on AVO. First, the effect of anisotropy on Ostrander's shale-sand model is investigated, and second, isotropic and anisotropic ray-trace synthetics are compared. The effect of anisotropy on AVO is found to be significant and may be lead to misinterpretations of AVO anomalies.

Leaney, S.W.; Borland, W.E. (Schlumberger Geophysics Nusantara, Jakarta (Indonesia))

1994-07-01

245

Dewarless Logging Tool - 1st Generation  

SciTech Connect

This report focuses on Sandia National Laboratories' effort to create high-temperature logging tools for geothermal applications without the need for heat shielding. One of the mechanisms for failure in conventional downhole tools is temperature. They can only survive a limited number of hours in high temperature environments. For the first time since the evolution of integrated circuits, components are now commercially available that are qualified to 225 C with many continuing to work up to 300 C. These components are primarily based on Silicon-On-Insulator (SOI) technology. Sandia has developed and tested a simple data logger based on this technology that operates up to 300 C with a few limiting components operating to only 250 C without thermal protection. An actual well log to 240 C without shielding is discussed. The first prototype high-temperature tool measures pressure and temperature using a wire-line for power and communication. The tool is based around the HT83C51 microcontroller. A brief discussion of the background and status of the High Temperature Instrumentation program at Sandia, objectives, data logger development, and future project plans are given.

HENFLING,JOSEPH A.; NORMANN,RANDY A.

2000-08-01

246

Dual excitation acoustic paramagnetic logging tool  

DOEpatents

New methods and apparatus are disclosed which allow measurement of the presence of oil and water in gelogical formations using a new physical effect called the Acoustic Paramagnetic Logging Effect (APLE). The presence of petroleum in formation causes a slight increase in the earth's magnetic field in the vicinity of the reservoir. This is the phenomena of paramagnetism. Application of an acoustic source to a geological formation at the Larmor frequency of the nucleous present causes the paramagnetism of the formation to disappear. This results in a decrease in the earth's magnetic field in the vicinity of the oil bearing formation. Repetitively frequency sweeping the acoustic source through the Larmor frequency of the nucleons present (approx. 2 kHz) causes an amplitude modulation of the earth's magnetic field which is a consequence of the APLE. The amplitude modulation of the earth's magnetic field is measured with an induction coil gradiometer and provides a direct measure of the amount of oil and water in the excitation zone of the formation. The phase of the signal is used to infer the longitudinal relaxation times of the fluids present, which results in the ability in general to separate oil and water and to measure the viscosity of the oil present. Such measurements may be preformed in open boreholes and in cased well bores. The Dual Excitation Acoustic Paramagnetic Logging Tool employing two acoustic sources is also described.

Vail, III, William B. (Bothell, WA)

1989-01-01

247

Dual excitation acoustic paramagnetic logging tool  

SciTech Connect

New methods and apparatus are disclosed which allow measurement of the presence of oil and water in geological formations using a new physical effect called the Acoustic Paramagnetic Logging Effect (APLE). The presence of petroleum in formation causes a slight increase in the earth's magnetic field in the vicinity of the reservoir. This is the phenomena of paramagnetism. Application of an acoustic source to a geological formation at the Larmor frequency of the nucleons present causes the paramagnetism of the formation to disappear. This results in a decrease in the earth's magnetic field in the vicinity of the oil bearing formation. Repetitively frequency sweeping the acoustic source through the Larmor frequency of the nucleons present (approx. 2 kHz) causes an amplitude modulation of the earth's magnetic field which is a consequence of the APLE. The amplitude modulation of the earth's magnetic field is measured with an induction coil gradiometer and provides a direct measure of the amount of oil and water in the excitation zone of the formation. The phase of the signal is used to infer the longitudinal relaxation times of the fluids present, which results in the ability in general to separate oil and water and to measure the viscosity of the oil present. Such measurements may be performed in open boreholes and in cased well bores. The Dual Excitation Acoustic Paramagnetic Logging Tool employing two acoustic sources is also described. 6 figs.

Vail, W.B. III.

1989-02-14

248

Dual excitation acoustic paramagnetic logging tool  

SciTech Connect

New methods and apparatus are disclosed which allow measurement of the presence of oil and water in gelogical formations using a new physical effect called the Acoustic Paramagnetic Logging Effect (APLE). The presence of petroleum in formation causes a slight increase in the earth's magnetic field in the vicinity of the reservoir. This is the phenomena of paramagnetism. Application of an acoustic source to a geological formation at the Larmor frequency of the nucleous present causes the paramagnetism of the formation to disappear. This results in a decrease in the earth's magnetic field in the vicinity of the oil bearing formation. Repetitively frequency sweeping the acoustic source through the Larmor frequency of the nucleons present (approx. 2 kHz) causes an amplitude modulation of the earth's magnetic field which is a consequence of the APLE. The amplitude modulation of the earth's magnetic field is measured with an induction coil gradiometer and provides a direct measure of the amount of oil and water in the excitation zone of the formation. The phase of the signal is used to infer the longitudinal relaxation times of the fluids present, which results in the ability in general to separate oil and water and to measure the viscosity of the oil present. Such measurements may be preformed in open boreholes and in cased well bores. The Dual Excitation Acoustic Paramagnetic Logging Tool employing two acoustic sources is also described.

Vail, III, William B. (Bothell, WA)

1989-01-01

249

Certified and Uncertified Logging Concessions Compared in Gabon: Changes in Stand Structure, Tree Species, and Biomass  

NASA Astrophysics Data System (ADS)

Forest management certification is assumed to promote sustainable forest management, but there is little field-based evidence to support this claim. To help fill this gap, we compared a Forest Stewardship Council (FSC)-certified with an adjacent uncertified, conventionally logged concession (CL) in Gabon on the basis of logging damage, above-ground biomass (AGB), and tree species diversity and composition. Before logging, we marked, mapped, and measured all trees >10 cm dbh in 20 and twelve 1-ha permanent plots in the FSC and CL areas, respectively. Soil and tree damage due to felling, skidding, and road-related activities was then assessed 2-3 months after the 508 ha FSC study area and the 200 ha CL study area were selectively logged at respective intensities of 5.7 m3/ha (0.39 trees/ha) and 11.4 m3/ha (0.76 trees/ha). For each tree felled, averages of 9.1 and 20.9 other trees were damaged in the FSC and CL plots, respectively; when expressed as the impacts per timber volume extracted, the values did not differ between the two treatments. Skid trails covered 2.9 % more of the CL surface, but skid trail length per unit timber volume extracted was not greater. Logging roads were wider in the CL than FSC site and disturbed 4.7 % more of the surface. Overall, logging caused declines in AGB of 7.1 and 13.4 % at the FSC and CL sites, respectively. Changes in tree species composition were small but greater for the CL site. Based on these findings and in light of the pseudoreplicated study design with less-than perfect counterfactual, we cautiously conclude that certification yields environmental benefits even after accounting for differences in logging intensities.

Medjibe, V. P.; Putz, Francis E.; Romero, Claudia

2013-03-01

250

Certified and uncertified logging concessions compared in Gabon: changes in stand structure, tree species, and biomass.  

PubMed

Forest management certification is assumed to promote sustainable forest management, but there is little field-based evidence to support this claim. To help fill this gap, we compared a Forest Stewardship Council (FSC)-certified with an adjacent uncertified, conventionally logged concession (CL) in Gabon on the basis of logging damage, above-ground biomass (AGB), and tree species diversity and composition. Before logging, we marked, mapped, and measured all trees >10 cm dbh in 20 and twelve 1-ha permanent plots in the FSC and CL areas, respectively. Soil and tree damage due to felling, skidding, and road-related activities was then assessed 2-3 months after the 508 ha FSC study area and the 200 ha CL study area were selectively logged at respective intensities of 5.7 m(3)/ha (0.39 trees/ha) and 11.4 m(3)/ha (0.76 trees/ha). For each tree felled, averages of 9.1 and 20.9 other trees were damaged in the FSC and CL plots, respectively; when expressed as the impacts per timber volume extracted, the values did not differ between the two treatments. Skid trails covered 2.9 % more of the CL surface, but skid trail length per unit timber volume extracted was not greater. Logging roads were wider in the CL than FSC site and disturbed 4.7 % more of the surface. Overall, logging caused declines in AGB of 7.1 and 13.4 % at the FSC and CL sites, respectively. Changes in tree species composition were small but greater for the CL site. Based on these findings and in light of the pseudoreplicated study design with less-than perfect counterfactual, we cautiously conclude that certification yields environmental benefits even after accounting for differences in logging intensities. PMID:23277438

Medjibe, V P; Putz, Francis E; Romero, Claudia

2013-01-01

251

Sorption of organic chemicals to soil organic matter: influence of soil variability and pH dependence.  

PubMed

For modeling the sorption of organic compounds in soils it is typically assumed that the organic carbon/water partitioning coefficient (Koc) of neutral organic chemicals can be treated as a constant property that remains unaffected by the type of soil organic matter as well as pH in the soil solution. Here the validity of these assumptions is evaluated with a large and diverse experimental data set of our own and literature data. To this end sorption experiments with 3 different soils and one peat were carried out using a column method. Differences in log Koc at pH values of 4.5 and 7.2 were on average <0.06 log units for 60 chemicals on Pahokee Peat. This result indicates that protonation/deprotonation of carboxylic groups in humic matter has no significant influence on sorption. The soil-to-soil variability of Koc was within factor of 3 regardless of the type of chemicals. The Pahokee Peat standard from the International Humic Substances Society appears to represent Koc in solid soil organic matter from different origins with an accuracy of ±0.23 log units (root-mean-square error). The comparison of the sorption data in Pahokee Peat with literature sorption data from the air in hydrated humic and fulvic acids suggested that the thermodynamic cycle for converting sorption data between air and water is applicable provided that for small, highly polar chemicals an additional water phase in the hydrated organic matter is considered. PMID:21194206

Bronner, Guido; Goss, Kai-Uwe

2010-12-31

252

Use of historical logging patterns to identify disproportionately logged ecosystems within temperate rainforests of southeastern Alaska.  

PubMed

The forests of southeastern Alaska remain largely intact and contain a substantial proportion of Earth's remaining old-growth temperate rainforest. Nonetheless, industrial-scale logging has occurred since the 1950s within a relatively narrow range of forest types that has never been quantified at a regional scale. We analyzed historical patterns of logging from 1954 through 2004 and compared the relative rates of change among forest types, landform associations, and biogeographic provinces. We found a consistent pattern of disproportionate logging at multiple scales, including large-tree stands and landscapes with contiguous productive old-growth forests. The highest rates of change were among landform associations and biogeographic provinces that originally contained the largest concentrations of productive old growth (i.e., timber volume >46.6 m³/ha). Although only 11.9% of productive old-growth forests have been logged region wide, large-tree stands have been reduced by at least 28.1%, karst forests by 37%, and landscapes with the highest volume of contiguous old growth by 66.5%. Within some island biogeographic provinces, loss of rare forest types may place local viability of species dependent on old growth at risk of extirpation. Examination of historical patterns of change among ecological forest types can facilitate planning for conservation of biodiversity and sustainable use of forest resources. PMID:23866037

Albert, David M; Schoen, John W

2013-08-01

253

Lipophilicity assessment of basic drugs (log P(o/w) determination) by a chromatographic method.  

PubMed

A previously reported chromatographic method to determine the 1-octanol/water partition coefficient (log P(o/w)) of organic compounds is used to estimate the hydrophobicity of bases, mainly commercial drugs with diverse chemical nature and pK(a) values higher than 9. For that reason, mobile phases buffered at high pH to avoid the ionization of the solutes and three different columns (Phenomenex Gemini NX, Waters XTerra RP-18 and Waters XTerra MS C(18)) with appropriate alkaline-resistant stationary phases have been used. Non-ionizable substances studied in previous works were also included in the set of compounds to evaluate the consistency of the method. The results showed that all the columns provide good estimations of the log P(o/w) for most of the compounds included in this study. The Gemini NX column has been selected to calculate log P(o/w) values of the set of studied drugs, and really good correlations between the determined log P(o/w) values and those considered as reference were obtained, proving the ability of the procedure for the lipophilicity assessment of bioactive compounds with very different structures and functionalities. PMID:21820118

Pallicer, Juan M; Sales, Joaquim; Rosés, Martí; Ràfols, Clara; Bosch, Elisabeth

2011-07-08

254

GGDMLE: a computer program which finds maximum likelihood estimates for the generalized log gamma distribution.  

PubMed

A FORTRAN program is described which finds maximum likelihood estimates for the generalized log gamma model for survival time data. The model includes regression variables which are assumed to be linearly related to log survival time and handles censored data. The shape parameter is treated as fixed in the optimization procedure (a modification of Powell's hybrid method), but the program can find maximum likelihood estimates (MLE) for several different values of the shape parameter in one run. The other parameters can be optionally fixed so special cases of the generalized log gamma (GLG) model, such as the log exponential, extreme value and normal models, can be studied. A subroutine is included which calculates initial parameter estimates for a given shape parameter value which can be used to start the optimization procedure. After some background mathematics, a description of how to use the program is given, including input/output features, a description of the subroutines and an explanation of the flow of control. An application, using data from Princess Margaret Hospital, Toronto, is presented to illustrate the program's use. PMID:6897716

Hogg, S A; Ciampi, A; Lawless, J

1982-12-01

255

Gradually truncated log-normal in USA publicly traded firm size distribution  

NASA Astrophysics Data System (ADS)

We study the statistical distribution of firm size for USA and Brazilian publicly traded firms through the Zipf plot technique. Sale size is used to measure firm size. The Brazilian firm size distribution is given by a log-normal distribution without any adjustable parameter. However, we also need to consider different parameters of log-normal distribution for the largest firms in the distribution, which are mostly foreign firms. The log-normal distribution has to be gradually truncated after a certain critical value for USA firms. Therefore, the original hypothesis of proportional effect proposed by Gibrat is valid with some modification for very large firms. We also consider the possible mechanisms behind this distribution.

Gupta, Hari M.; Campanha, José R.; de Aguiar, Daniela R.; Queiroz, Gabriel A.; Raheja, Charu G.

2007-03-01

256

Calibration of a neutron log in partially saturated media. Part II. Error analysis  

SciTech Connect

Four sources or error (uncertainty) are studied in water content obtained from neutron logs calibrated in partially saturated media for holes up to 3 m. For this calibration a special facility was built and an algorithm for a commercial epithermal neutron log was developed that obtains water content from count rate, bulk density, and gap between the neutron sonde and the borehole wall. The algorithm contained errors due to the calibration and lack of fit, while the field measurements included uncertainties in the count rate (caused by statistics and a short time constant), gap, and density. There can be inhomogeneity in the material surrounding the borehole. Under normal field conditions the hole-size-corrected water content obtained from such neutron logs can have an uncertainty as large as 15% of its value.

Hearst, J.R.; Kasameyer, P.W.; Dreiling, L.A.

1981-03-20

257

Studies on log P, retention time and QSAR of 2-substituted phenylnitronyl nitroxides as free radical scavengers  

Microsoft Academic Search

As reported in our previous paper [Y. Wu, L. Bi, W. Bi, Z. Li, M. Zhao, C. Wang, J. Ju, S. Peng, Bioorg. Med. Chem. 14 (2006) 5711–5720.], a series of novel 2-substituted nitronyl nitroxides were synthesized and characterized to show enhanced free radical scavenger properties. Here, the logP values and retention time (alternatively represented as logK) of these 20

Ming Zhao; Zheng Li; Yihui Wu; Yu-Rong Tang; Chao Wang; Ziding Zhang; Shiqi Peng

2007-01-01

258

In-Home Demonstration of the Reduction of Woodstove Emissions from the Use of Densified Logs.  

SciTech Connect

There is a need to reduce emissions from conventional wood stoves in the short-term while stove replacement takes place over the longer term. One possible is to use fuels that would burn cleaner than cordwood. Densified fuels have been commercially available for years and offer such a possibility. The objective of this project was to evaluate the emissions and efficiency performance of two commercially available densified log types in homes and compare their performance with cordwood. Researchers measured particulate matter (PM), carbon monoxide (CO), and volatile organic matter (VOC) emissions. Both total VOC and methane values are presented. Each home used an Automated Woodstove Emissions Sampler system, developed for the EPA and Bonneville Power Administration, in a series of four week-long tests for each stove. The sequence of tests in each stove was cordwood, Pres-to-Logs, Eco-Logs, and a second, confirming test using Pres-to-Logs. Results show an average reduction of 52% in PM grams per hour emissions overall for the nine stoves using Pres-to-Logs. All nine stoves displayed a reduction in PM emissions. CO emissions were more modestly reduced by 27%, and VOCs were reduced 39%. The emissions reduction percentage was similar for both types of stoves.

Barnett, Stockton G.; Bidhouse, Roger D.

1992-07-07

259

In-home demonstration of the reduction of woodstove emissions from the use of densified logs  

SciTech Connect

There is a need to reduce emissions from conventional wood stoves in the short-term while stove replacement takes place over the longer term. One possible is to use fuels that would burn cleaner than cordwood. Densified fuels have been commercially available for years and offer such a possibility. The objective of this project was to evaluate the emissions and efficiency performance of two commercially available densified log types in homes and compare their performance with cordwood. Researchers measured particulate matter (PM), carbon monoxide (CO), and volatile organic matter (VOC) emissions. Both total VOC and methane values are presented. Each home used an Automated Woodstove Emissions Sampler system, developed for the EPA and Bonneville Power Administration, in a series of four week-long tests for each stove. The sequence of tests in each stove was cordwood, Pres-to-Logs, Eco-Logs, and a second, confirming test using Pres-to-Logs. Results show an average reduction of 52% in PM grams per hour emissions overall for the nine stoves using Pres-to-Logs. All nine stoves displayed a reduction in PM emissions. CO emissions were more modestly reduced by 27%, and VOCs were reduced 39%. The emissions reduction percentage was similar for both types of stoves.

Barnett, S.G.; Bighouse, R.D.

1992-07-07

260

Armored instrumentation cable for geothermal well logging  

SciTech Connect

Multiconductor armored well-logging cable is used extensively by the oil and natural gas industry to lower various instruments used to measure the geological and geophysical parameters into deep wellbores. Advanced technology in oil-well drilling makes it possible to achieve borehole depths of 9 km (30,000 ft). The higher temperatures in these deeper boreholes demand advancements in the design and manufacturing of wireline cable and in the electrical insulating and armoring materials used as integral components. If geothermal energy is proved an abundant economic resource, drilling temperatures approaching and exceeding 300/sup 0/C will become commonplace. The adaptation of teflons as electrical insulating material permitted use of armored cable in geothermal wellbores where temperatures are slightly in excess of 200/sup 0/C, and where the concentrations of corrosive minerals and gases are high. Teflon materials presently used in wireline cables, however, are not capable of continuous operation at the anticipated higher temperatures.

Dennis, B.R.; Johnson, J.; Todd, B.

1981-01-01

261

Log correlation of Cambrian of Michigan basin  

SciTech Connect

Log correlations are presented for the lower peninsula of Michigan and for adjoining parts of Indiana, Ohio, and Canada. Isopach maps were constructed for the Mount Simon, Eau Claire, Galesville, Franconia, and Trempealeau formations. Two depocenters were present during the Mount Simon - one just west of Saginaw Bay and another in northeastern Illinois, the margin of which extends into southwestern Michigan. The Eau Claire isopach map indicates a relatively stable Michigan basin with the Eau Claire thickening southwest into Illinois. Stability continued during the deposition of the Galesville Sandstone, which entered the basin from the west from a source in the Wisconsin highlands. Relatively strong subsidence resumed in the Saginaw Bay depocenter during the accumulation of the Franconia Formation. The Trempealeau Formation records only a slight increase at this depocenter, but thickens markedly to the south into Indiana.

Fisher, J.H.

1986-08-01

262

Log-Linear Models for Gene Association.  

PubMed

We describe a class of log-linear models for the detection of interactions in high-dimensional genomic data. This class of models leads to a Bayesian model selection algorithm that can be applied to data that have been reduced to contingency tables using ranks of observations within subjects, and discretization of these ranks within gene/network components. Many normalization issues associated with the analysis of genomic data are thereby avoided. A prior density based on Ewens' sampling distribution is used to restrict the number of interacting components assigned high posterior probability, and the calculation of posterior model probabilities is expedited by approximations based on the likelihood ratio statistic. Simulation studies are used to evaluate the efficiency of the resulting algorithm for known interaction structures. Finally, the algorithm is validated in a microarray study for which it was possible to obtain biological confirmation of detected interactions. PMID:19655032

Hu, Jianhua; Joshi, Adarsh; Johnson, Valen E

2009-01-01

263

Log-Linear Models for Gene Association  

PubMed Central

We describe a class of log-linear models for the detection of interactions in high-dimensional genomic data. This class of models leads to a Bayesian model selection algorithm that can be applied to data that have been reduced to contingency tables using ranks of observations within subjects, and discretization of these ranks within gene/network components. Many normalization issues associated with the analysis of genomic data are thereby avoided. A prior density based on Ewens’ sampling distribution is used to restrict the number of interacting components assigned high posterior probability, and the calculation of posterior model probabilities is expedited by approximations based on the likelihood ratio statistic. Simulation studies are used to evaluate the efficiency of the resulting algorithm for known interaction structures. Finally, the algorithm is validated in a microarray study for which it was possible to obtain biological confirmation of detected interactions.

Hu, Jianhua; Joshi, Adarsh; Johnson, Valen E.

2009-01-01

264

Enrichment planting of dipterocarps in logged-over secondary forests: effect of width, direction and maintenance method of planting line on selected Shorea species  

Microsoft Academic Search

Natural dipterocarp seedling stock is usually very scarce or totally absent from heavily logged dipterocarp forests which have been subjected to shifting cultivation. Instead, a dense cover of secondary forest of low commercial or ecological value prevails. These logged-over low-volume forests can either be converted into plantations or restocked by local, valuable timber. The aim of this study was to

Göran Ådjers; Sakti Hadengganan; Jussi Kuusipalo; Koerdi Nuryanto; Lauri Vesa

1995-01-01

265

An evaluation of the use of drillers' logs in lithologic studies of the Ogallala Formation of the southern high plains of Texas, progress report, 1970-71  

USGS Publications Warehouse

Logs made by water-well drillers were analyzed in conjunction with test-hole drilling and geophysical logging to evaluate usefulness of the driller's log in delineating areas that would be suitable for artificial recharge of the Ogallala Formation. This preliminary study indicates that lack of detailed and accurate information in many drillers' logs prevents their use as a reliable source of lithologic information. For many applications, such as evaluation of potential areas for artificial recharge, the value of more complete and more accurate information will be readily apparent as these applications become more widespread. More effort will be required in collecting lithologic information as part of the drilling operations.

Wilson, C. A.; Smith, J. T.; Thompson, G. L.; Sandeen, W. M.

1972-01-01

266

Obtaining permeability estimates from NMR logging data in an unconsolidated groundwater aquifer  

NASA Astrophysics Data System (ADS)

There is growing interest in the use of proton nuclear magnetic resonance (NMR) logging for aquifer characterization because it provides information about water-filled porosity and pore space geometry that can be used to estimate permeability (k). Hydrologists estimate hydraulic conductivity, from which k can be calculated, using wellbore flow (WBF) logging. WBF logging data distributes the total hydraulic conductivity, determined from aquifer testing, throughout the aquifer. However, this method is time consuming and has relatively low vertical resolution. If reliable estimates of k can be obtained from NMR logging data, this would provide hydrologists with an efficient alternate method for characterizing aquifer properties. The Schlumberger Doll Research (SDR) and Timur-Coates (T-C) equations are widely used in petroleum applications to obtain k from NMR logging measurements of the relaxation time T2. In this abstract, we focus on the SDR equation which takes the form kSDR=a? mT2MLn where a, m and n are empirical constants, T2ML is the mean log of the T2 distribution and ? is porosity. The constants have been empirically determined in consolidated materials and are typically assumed to have the following values: a=4, m=4 and n=2. The use of the SDR equation with these values has been found to yield reliable estimates of k in consolidated materials. However, this same equation underestimates k in unconsolidated materials. In this study, we collected NMR logging, aquifer-test, and WBF data from a 150-m deep well that penetrated the High Plains aquifer in central Nebraska. We then worked with a generalized form of the SDR equation: kSDR Generalized =a? mT2AVG2, where we allowed T2AVG to be calculated as the mean log and arithmetic mean (T2AM) of the T2 distribution. We elected to set the exponent n on the T2 term equal to 2, which results in a k estimate that has the appropriate units of length squared. We used a semi-constrained least squares inversion to optimize the fit between log WBF-k and log NMR-k. We constrained m to be positive, ranging from 0.5 and 8, increasing in value with an interval of 0.5; a was unconstrained. NMR logging measurements were made throughout the well every 0.45 m. WBF logging provided k estimates over nine 6-m intervals. Within these nine intervals, NMR-k estimates were upscaled to the resolution of the WBF as follows: kUpscaled=??i(a?mT2AVG2), where ?i was 0.45 m. In the form of the SDR equation used in petroleum applications, NMR-k was underestimated by an order of magnitude in 6 intervals and overestimated in one interval. We found that the following equation yielded the best agreement between NMR-k and WBF-k: kUnconsolidated =16? 6T2AM2. In 6 of the 9 intervals, NMR-k estimates were within a factor of 2 of WBF-k. However, in two intervals NMR-k disagrees with WBF-k by over a factor of 5.

Dlubac, K.; Knight, R. J.; Song, Y.; Bachman, N.; Grau, B.; Cannia, J. C.; Williams, J.

2011-12-01

267

Estimating monthly streamflow values by cokriging  

Microsoft Academic Search

Cokriging is applied to estimation of missing monthly streamflow values in three records from gaging stations in west central Virginia. Missing values are estimated from optimal consideration of the pattern of auto- and cross-correlation among standardized residual log-flow records. Investigation of the sensitivity of estimation to data configuration showed that when observations are available within two months of a missing

Andrew R. Solow; Steven M. Gorelick

1986-01-01

268

Place Value  

NSDL National Science Digital Library

These activites cover place value of ones, tens, hundreds and thousands. Please complete the games in order. You must finish each game before going on to the next one. Game #1: Dinosaur Numbers (place value) Game #2: Shark Numbers (place value) Game #3: Place Value Golf (harder) ...

Christian, Mrs.

2007-03-21

269

Systematic use of trace element distribution patterns in log-log diagrams for plutonic suites  

NASA Astrophysics Data System (ADS)

Trace element modelling has been widely used for petrogenetic interpretation of basaltic systems. This paper indicates how to select trace element pairs having very different bulk distribution coefficients ( D ) which when plotted on simple log-log diagrams permit the identification of the main magmatic process (magma mixing, partial melting, fractional crystallization) involved in the genesis of plutonic rocks. Fractional crystallization gives a straight line on such a diagram with a strong decrease of the compatible element whereas the concentrations of the element with D << 1 increase slowly. A similar evolution of the solids in equilibrium is observed and when data of at least one of the cumulates are directly available, it is possible to calculate the D and F parameters of the sequence of fractional crystallization. An example of this procedure is shown for a French Hercynian plutonic suite: the basic suite of Variscan Corsica.

Cocherie, Alain

1986-11-01

270

The logN-logS relationship of normal X-ray emitting galaxies  

NASA Astrophysics Data System (ADS)

We have selected a flux limited serendipitous sample of galaxies from the cross-correlation of the BMW (Brera Multiscale Wavelet) ROSAT HRI and the LEDA (Lyon - Meudon Extragalactic Database) Catalogues. This sample is used to study the X-ray properties of normal galaxies in the local universe. We also find that the logN-logS distribution we derived for a serendipitous subsample, optically and X-ray flux limited, is consistent with the euclidean slope in the flux range FX(0.5 - 2) ˜ 1.1 - 110 × 10-14 erg cm-2 s-1. We further show that the same law is valid over 4 decades, from the bright sample derived from the RASS data to the very faint detections in deep XMM-Newton fields.

Tajer, M.; Trinchieri, G.; Wolter A.; Campana, S.; Moretti, A.; Tagliaferri, G.

271

Connections between polarization curves and log(a[i]/a[ref])-pe diagram.  

PubMed

When reading papers concerning studies of corrosion of dental amalgam and its phases by means of polarization curves, one often finds it difficult to understand the reasons for the chemical reactions proposed from the form of the polarization curve. Thermodynamic data represented in the form of log(a[i]/a[ref])-pe diagrams, i.e., the logarithm of the activity of a metal or an alloy with reference to the activity of the corresponding metal ion, as a function of pe (a recalculated form of the potential), make it possible for one to determine which chemical reactions can occur on the specimen surface or in the solution within the potential difference used in the polarization experiment and to decide which of these reactions is the most probable. The hypothesis examined in this study is that a log(a[i]/a[ref])-pe diagram can be used in the interpretation of polarization curves. Potentiodynamic polarization curves and log(a[i]/a[ref])-pe diagrams were compared for the corrosion of Ag, Hg, and gamma 1 with and without Sn. It was found that there was a connection between the polarization curves and the log(a[i]/a[ref])-pe diagrams. From the composition of the specimens and the solution and by means of thermodynamic data, pe values for solid corrosion products and relative concentrations of soluble complexes at these pe values were obtained independently of the polarization curves. A much more reliable value for the nobility of metals and alloys was attained by use of the log(a[i]/a[ref])-pe diagrams than by use of the potential of the starting point of the polarization curves. It was found that pe corresponding to the potential of the starting point of the polarization curves in de-aerated synthetic saliva was obtained about two pe units before pe of the most insoluble solid compound formed on the specimen surface or in the solution. PMID:9390481

Olsson, S; Bergman, M; Marek, M; Berglund, A

1997-12-01

272

On the log-convexity of combinatorial sequences  

Microsoft Academic Search

This paper is devoted to the study of the log-convexity of combinatorial sequences. We show that the log-convexity is preserved under componentwise sum, under binomial convolution, and by the linear transformations given by the matrices of binomial coefficients and Stirling numbers of two kinds. We develop techniques for dealing with the log-convexity of sequences satisfying a three-term recurrence. We also

Lily L. Liu; Yi Wang

2007-01-01

273

A time-driven transmission method for well logging networks  

Microsoft Academic Search

Long delays and poor real-time transmission are disadvantageous to well logging networks consisting of multiple subnets. In\\u000a this paper, we proposed a time-driven transmission method (TDTM) to improve the efficiency and precision of logging networks.\\u000a Using TDTM, we obtained well logging curves by fusing the depth acquired on the surface, and the data acquired in downhole\\u000a instruments based on the

Ruiqing Wu; Wei Chen; Tianqi Chen; Qun Li

2009-01-01

274

Outcrop gamma-ray logging applied to subsurface petroleum geology  

Microsoft Academic Search

Developing a gamma-ray log profile of an outcrop with a hand-held scintillometer has many applications to subsurface petroleum geology. The outcrop gamma-ray log provides a readily understandable bridge between what is observed in outcrop and what is to be interpreted on well logs and seismic records. Several examples are presented in this paper that demonstrate major applications. An outcrop from

R. M. Slatt; J. M. Borer; B. W. Horn

1995-01-01

275

Reliability Test Plans for Exponentiated Log-Logistic Distribution  

Microsoft Academic Search

A generalization of the log-logistic distribution called exponentiated log-logistic distribution (in lines of exponentiated Weibull distribution suggested by Mudholkar and Sri- vastava (2)) is considered. In this paper the operating characteristic for a sampling plan is determined for the case that a lot of products is submitted for inspection with lifetimes spec- ified by an exponentiated log-logistic distribution (ELLD). The

K. Rosaiah; R. R. L. Kantam; Santosh Kumar

2006-01-01

276

Iris Recognition Algorithm Using Modified Log-Gabor Filters  

Microsoft Academic Search

In this paper, we presented an iris recognition algorithm based on modified Log-Gabor filters. The algorithm is similar as the method proposed by Daugman in general procedure while modified Log-Gabor filters are adopted to extract the iris phase information instead of complex Gabor filters used in Daugman's method. The advantage of Log-Gabor filters over complex Gabor filters is the former

Peng Yao; Jun Li; Xueyi Ye; Zhenquan Zhuang; Bin Li

2006-01-01

277

An Artificial Latrine Log for Swamp Rabbit Studies  

Microsoft Academic Search

Managers use latrine surveys to monitor swamp rabbit (Sylvilagus aquaticus) populations but may miss rabbits in sites lacking suitable latrine logs. We tested artificial latrine logs in logless thickets in southern Illinois, USA, generally detecting swamp rabbits in fewer visits than by live-trapping. Artificial logs can aid swamp rabbit monitoring, especially in logless habitats. (JOURNAL OF WILDLIFE MANAGEMENT 72(2):561-563; 2008)

Eric M. Schauber; Paul D. Scharine; Clayton K. Nielsen; Lyann Rubert

2008-01-01

278

Herschel Observation Log (Herschel Science Centre, 2013)  

NASA Astrophysics Data System (ADS)

The Herschel Space Observatory (Herschel) is an ESA (European Space Agency) project with instruments funded by ESA member states. It was operated from May 2009 till April 2013, offering unprecedent observational capabilities in the far-infrared and submillimetre spectral range (55-671 microns). Herschel carried a 3.5m diameter passively cooled Cassegrain telescope. The science payload comprised three instruments: two direct detection cameras/medium resolution spectrometers, PACS and SPIRE, and a very high-resolution heterodyne spectrometer, HIFI. Herschel successfully made over 37,000 scientific observations. Herschel Science Archive: The HSA is available at the Herschel Science Centre at http://herschel.esac.esa.int/Science_Archive.shtml Herschel helpdesk: http://herschel.esac.esa.int/esupport/ Herschel User Provided Data Products: http://herschel.esac.esa.int/UserProvidedDataProducts.shtml Postcard Server: http://archives.esac.esa.int/hsa/aio/doc/postcardGallery.html Observation Log: http://herschel.esac.esa.int/logrepgen/observationlist.do (1 data file).

Herschel Science, Centre

2013-09-01

279

Efficient Preprocessing technique using Web log mining  

NASA Astrophysics Data System (ADS)

Web Usage Mining can be described as the discovery and Analysis of user access pattern through mining of log files and associated data from a particular websites. No. of visitors interact daily with web sites around the world. enormous amount of data are being generated and these information could be very prize to the company in the field of accepting Customerís behaviors. In this paper a complete preprocessing style having data cleaning, user and session Identification activities to improve the quality of data. Efficient preprocessing technique one of the User Identification which is key issue in preprocessing technique phase is to identify the Unique web users. Traditional User Identification is based on the site structure, being supported by using some heuristic rules, for use of this reduced the efficiency of user identification solve this difficulty we introduced proposed Technique DUI (Distinct User Identification) based on IP address ,Agent and Session time ,Referred pages on desired session time. Which can be used in counter terrorism, fraud detection and detection of unusual access of secure data, as well as through detection of regular access behavior of users improve the overall designing and performance of upcoming access of preprocessing results.

Raiyani, Sheetal A.; jain, Shailendra

2012-11-01

280

Identifying subsurface facies from user-directed computer processing of log and other data  

Microsoft Academic Search

Geologists, reservoir engineers, and log analysts can discern lithology types by inspecting curve shapes on logs. Data obtained from cores, outcrops, and other sources can be correlated with wireline logs to classify log response shapes for each observable facies. The semiautomatic program presented here helps experienced log analysts and geologists identify subsurface facies from wireline and other log data. The

J. L. Baldwin; M. O. Morrow

1986-01-01

281

Influence of Logging on the Effects of Wildfire in Siberia  

NASA Astrophysics Data System (ADS)

The Russian boreal zone supports a huge terrestrial carbon pool. Changes in this pool and related changes in land cover have global significance in terms of climate change. Moreover, it is a tremendous and largely untapped reservoir of wood products. The main natural disturbance in these forests is wildfire, which modifies the carbon budget and has potentially important climate feedbacks. In addition both legal and illegal logging are increasing in many forest areas of Siberia. From 2009 to 2012, we investigated a number of logged and unlogged sites to evaluate the impact of logging on wildfire characteristics and subsequent effects of wildfires on the ecosystem. The research was conducted in 3 different ecoregions of Siberia: taiga forest (Angara region), forest-steppe (Shushenskoe region), and mountain forest (Chita region). We analyzed fire effects in different forest types as a function of both the presence of logging and harvest methods. Logged areas often had higher fuel loads due to logging debris, and typically experienced higher severity fires than unlogged forests. We found large variations among sites depending on forest types, type of logging activity, and weather conditions prior to and during burning. Illegal logging resulted in much higher fire hazard than legal logging. Fuel consumption was highest on repeatedly burned areas, where ground cover was often burned to the mineral layer. Estimated carbon emissions were up to 5 times higher on logged areas than on unlogged sites. Soil respiration was less on both burned and logged areas than in undisturbed forest. Changing patterns in the harvest of wood products can be expected to increase the emissions and ecosystem damage from wildfires, inhibit recovery of natural ecosystems, and exacerbate impacts of wildland fire on changing climate and air quality. The research was supported by NASA LCLUC Program, RFBR grant # 12-04-31258, and Russian Academy of Sciences.

Kukavskaya, Elena; Ivanova, Galina; Buryak, Ludmilla; Kalenskaya, Olga; Bogorodskaya, Anna; Zhila, Sergey; McRae, Douglas; Conard, Susan

2013-04-01

282

Value Engineering  

Microsoft Academic Search

This paper defines value engineering, shows why it is necessary, and emphasizes the engineer's responsibility for using engineering disciplines in the design of a product. Recognizing that value engineering is a duty of the professional engineer, the paper stresses application of value engineering to attain Armed Services goals, and reduce costs while speeding up delivery of the weapon system. Many

A. Zappacosta

1962-01-01

283

A RAPID METHOD FOR ESTIMATING LOG P FOR ORGANIC CHEMICALS  

EPA Science Inventory

The logarithm of the retention time (log RT) of organic chemicals on a permanently bonded (C-18) reverse-phase high-pressure liquid chromatography system is shown to be linearly related to the logarithm of the n-octanol/water partition coefficient (log P). A rapid, inexpensive te...

284

Using Transaction Log Analysis to Improve OPAC Retrieval Results  

Microsoft Academic Search

This OPAC transaction log analysis study compared data derived two sets of logs within a six-month period. Analysis of the first set of data revealed that users experienced difficulty with basic searching techniques. The OPAC introductory screens were simplified and clarified to help users improve search success rates. The second set of data, analyzed after screen changes had been made,

Deborah D. Blecic; Nirmala S. Bangalore; Josephine L. Dorsch; Cynthia L. Henderson; Melissa H. Koenig; Ann C. Weller

1998-01-01

285

Thesis Proposal Analysis of Helium programs obtained through logging  

Microsoft Academic Search

Helium is a user-friendly compiler especially designed for teaching and learning the functional programming language Haskell. The compiler provides a feature called Big Brother, which logs all programs compiled at Utrecht University within the Faculty of Mathematics and Computer Science. These loggings give an enormous amount of in- teresting data concerning novice programmers, mostly within the course of functional programming.

Peter van Keeken

286

Exploiting MMORPG log data toward efficient RMT player detection  

Microsoft Academic Search

To detect players who are engaged in real-money trading (RMT) in massively multi-player online role-playing games (MMORPGs), behavior of players was analyzed using log data of a commercial MMORPG. A closed test evaluated the effectiveness of several player-wise statistics derived from the log data in detecting RMT players.

Hiroshi Itsuki; Asuka Takeuchi; Atsushi Fujita; Hitoshi Matsubara

2010-01-01

287

Beaufort Sea log analysis of thin turbidite sands  

Microsoft Academic Search

Offshore exploration drilling in the Beaufort Sea has encountered numerous oil, gas, and water bearing deep sea submarine fans of Oligocene and Eocene age. These fans or turbidite mounds have often been highly laminated sand and shale sequences which complicate their evaluation from electric logs unable to respond independently to the laminations. The logging environment includes highly saline potassium chloride

Spalding

1984-01-01

288

Real-Time System Log Monitoring/Analytics Framework  

SciTech Connect

Analyzing system logs provides useful insights for identifying system/application anomalies and helps in better usage of system resources. Nevertheless, it is simply not practical to scan through the raw log messages on a regular basis for large-scale systems. First, the sheer volume of unstructured log messages affects the readability, and secondly correlating the log messages to system events is a daunting task. These factors limit large-scale system logs primarily for generating alerts on known system events, and post-mortem diagnosis for identifying previously unknown system events that impacted the systems performance. In this paper, we describe a log monitoring framework that enables prompt analysis of system events in real-time. Our web-based framework provides a summarized view of console, netwatch, consumer, and apsched logs in real- time. The logs are parsed and processed to generate views of applications, message types, individual/group of compute nodes, and in sections of the compute platform. Also from past application runs we build a statistical profile of user/application characteristics with respect to known system events, recoverable/non-recoverable error messages and resources utilized. The web-based tool is being developed for Jaguar XT5 at the Oak Ridge Leadership Computing facility.

Oral, H Sarp [ORNL; Dillow, David A [ORNL; Park, Byung H [ORNL; Shipman, Galen M [ORNL; Geist, Al [ORNL; Gunasekaran, Raghul [ORNL

2011-01-01

289

Condition and fate of logged forests in the Brazilian Amazon.  

Treesearch

... we studied the forest damage caused by recent logging operations and the ... Across 2,030,637 km2 of the Brazilian Amazon from 1999 to 2004, at least 76% of all ... We found that 16 1% of selectively logged areas were deforested within 1  ...

290

An Architecture for Mining Massive Web Logs with Experiments?  

Microsoft Academic Search

We introduce an experimental web log mining architecture with ad- vanced storage and data mining components. The aim of the system is to give a flexible base for web usage mining of large scale Internet sites. We present exper- iments over logs of the largest Hungarian Web portal (origo) (www.origo.hu) that among others provides online news and magazines, community pages,

A. Bencz; MTA SZTAKI

291

Effects of selective logging on tropical forest tree growth  

NASA Astrophysics Data System (ADS)

We combined measurements of tree growth and carbon dioxide exchange to investigate the effects of selective logging on the Aboveground Live Biomass (AGLB) of a tropical rain forest in the Amazon. Most of the measurements began at least 10 months before logging and continued at least 36 months after logging. The logging removed ˜15% of the trees with Diameter at Breast Height (DBH) greater than 35 cm, which resulted in an instantaneous 10% reduction in AGLB. Both wood production and mortality increased following logging, while Gross Primary Production (GPP) was unchanged. The ratio of wood production to GPP (the wood Carbon Use Efficiency or wood CUE) more than doubled following logging. Small trees (10 cm < DBH < 35 cm) accounted for most of the enhanced wood production. Medium trees (35 cm < DBH < 55 cm) that were within 30 m of canopy gaps created by the logging also showed increased growth. The patterns of enhanced growth are most consistent with logging-induced increases in light availability. The AGLB continued to decline over the study, as mortality outpaced wood production. Wood CUE and mortality remained elevated throughout the 3 years of postlogging measurements. The future trajectory of AGLB and the forest's carbon balance are uncertain, and will depend on how long it takes for heterotrophic respiration, mortality, and CUE to return to prelogging levels.

Figueira, Adelaine Michela E. S.; Miller, Scott D.; de Sousa, Cleilim Albert D.; Menton, Mary C.; Maia, Augusto R.; Da Rocha, Humberto R.; Goulden, Michael L.

2008-03-01

292

A borehole corrected pulsed neutron well logging system  

Microsoft Academic Search

An improved well logging method has been developed for more accurately measuring the neutron capture cross section (Sigma) of earth formations. A measurement of Sigma with depth (well log) is useful in estimating hydrocarbon saturation of saline reservoirs. Gamma rays are detected following each burst of neutrons emitted by a pulsed 14 MeV neutron generator. An iterative procedure was developed

W. E. Schultz; H. D. Smith; J. L. Verbout; J. R. Bridges; G. H. Garcia

1985-01-01

293

Error log analysis: statistical modeling and heuristic trend analysis  

Microsoft Academic Search

Most error-log analysis studies perform a statistical fit to the data assuming a single underlying error process. The authors present the results of an analysis that demonstrates that the log is composed of at least two error processes: transient and intermittent. The mixing of data from multiple processes requires many more events to verify a hypotheses using traditional statistical analysis.

Ting-Ting Y. Lin; Daniel P. Siewiorek

1990-01-01

294

Detecting User Sessions in the Tumba! Query Log  

Microsoft Academic Search

This paper describes an approach to detect distinct user sessions from the logs of a particular search engine. We present our work by describing the proposed algorithm and some interesting usage patterns that were detected. Some pitfalls of our approach are also noted. Finally, we give some insights on how web log mining could be exploited in other areas such

Nuno Seco; Nuno Cardoso

295

Tracking Observations: Using Handhelds and Computers for Classroom Observation Logging  

Microsoft Academic Search

This paper presents the synergistic use of handheld computers and desktop computers as tools for grade school teachers to record observational data from their classrooms. The system uses handheld devices to tersely log events in situ, and allows later reflection and elaboration through annotation of the logged events on desktop computer. The terse, ephemeral capture of events coupled with post-hoc

Hashi Bai; Greydon Buckley; Mark Howard; Edward Lank

2007-01-01

296

6. Livestock barn (far left), log drafthorse barn (left of ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. Livestock barn (far left), log draft-horse barn (left of center), loafing shed (center), log calving barn (right of center). View to west-northwest. - William & Lucina Bowe Ranch, County Road 44, 0.1 mile northeast of Big Hole River Bridge, Melrose, Silver Bow County, MT

297

Log-Multiplicative Association Models as Item Response Models  

ERIC Educational Resources Information Center

Log-multiplicative association (LMA) models, which are special cases of log-linear models, have interpretations in terms of latent continuous variables. Two theoretical derivations of LMA models based on item response theory (IRT) arguments are presented. First, we show that Anderson and colleagues (Anderson & Vermunt, 2000; Anderson & Bockenholt,…

Anderson, Carolyn J.; Yu, Hsiu-Ting

2007-01-01

298

Log Analyzer for Network Forensics and Incident Reporting  

Microsoft Academic Search

Network intrusion detection systems are used in network forensics and network auditing to log suspicious activities that potentially signify security violations on the networks as alerts. However, the efficacies of intrusion aggregations to succinctly process audit logs that are gaining wider acceptability in computer security are flawed because the methods frequently require high level of expertise to validate each alert

Joshua Ojo Nehinbe

2010-01-01

299

Mining Web Access Logs of an On-line Newspaper  

Microsoft Academic Search

With the explosive growth of data available on the Internet, personalization of this information space become a necessity. An im- portant component of web personalization is the automatic knowledge extraction from web log files. However, analysis of large web log files is a complex task not fully addressed by existing web access analyzers. Us- ing commercial software, we applied well-known

Paulo Batista; Mario J. Silva

300

Message Correlation and Business Protocol Discovery in Service Interaction Logs  

Microsoft Academic Search

The problem of discovering protocols and business processes based on the analysis of log les is a real challenge. The behavior of a Web service can be specied using a Business Protocol, hence the importance of this discovery. The construction of the Business Protocol begins by correlating the logged messages into their conversations (i.e. instances of the business protocol). The

Belkacem Serrour; Daniel P. Gasparotto; Hamamache Kheddouci; Boualem Benatallah

2008-01-01

301

Prediction of Log "P": ALOGPS Application in Medicinal Chemistry Education  

ERIC Educational Resources Information Center

|Molecular hydrophobicity (lipophilicity), usually quantified as log "P" where "P" is the partition coefficient, is an important molecular characteristic in medicinal chemistry and drug design. The log "P" coefficient is one of the principal parameters for the estimation of lipophilicity of chemical compounds and pharmacokinetic properties. The…

Kujawski, Jacek; Bernard, Marek K.; Janusz, Anna; Kuzma, Weronika

2012-01-01

302

On the Choice of Variance for the Log Rank Test.  

National Technical Information Service (NTIS)

The log rank test is widely used for comparison of survival curves. This paper examines various estimators for the variance of the log rank test statistic. These include the Mantel-Haenszel variance, the permutation variance of Peto and Peto and several n...

M. Brown

1979-01-01

303

The effects of logging and disease on American chestnut  

Microsoft Academic Search

Disturbance histories drive spatiotemporal patterns of species distributions, and multiple disturbances can have complex effects on these patterns of distribution. The introduction of the chestnut blight (Cryphonectria parasitica (Murril.) Barr.) to the eastern United States in the early 1900s coincided with an increase in logging, thus presenting an ideal situation for studying the effect of two disturbance events, logging and

Katie L. Burke

2011-01-01

304

Mining Console Logs for Large-Scale System Problem Detection  

Microsoft Academic Search

The console logs generated by an application contain messages that the application developers believed would be useful in de- bugging or monitoring the application. Despite the ubiquity and large size of these logs, they are rarely exploited in a syste matic way for monitoring and debugging because they are not read- ily machine-parsable. In this paper, we propose a novel

Wei Xu; Ling Huang; Armando Fox; David A. Patterson; Michael I. Jordan

2008-01-01

305

Log-Linear Analysis: An Introduction for Researchers in Counseling.  

ERIC Educational Resources Information Center

Serves as an introduction to log-linear analysis, a technique used in the analysis of qualitative data arranged in multidimensional contingency tables. The steps involved in log-linear analysis are presented in the context of an investigation of a personality characteristic of a group of counselor trainees. (Author)

Milone, Michael N., Jr.; Wolk, Stephen

1980-01-01

306

Efficiently Extracting Operational Profiles from Execution Logs Using Suffix Arrays  

Microsoft Academic Search

An important software reliability engineering tool is operational profiles. In this paper we propose a cost effective automated approach for creating second generation operational profiles using execution logs of a software product. Our algorithm parses the execution logs into sequences of events and produces an ordered list of all possible subsequences by constructing a suffix-array of the events. The difficulty

Meiyappan Nagappan; Kesheng Wu; Mladen A. Vouk

2009-01-01

307

A graphical automated detection system to locate hardwood log ...  

Treesearch

... system and a state-of-the-art Graphic User Interface (GUI) for hardwood logs. The algorithm identifies defects at least 0.5 inch high and at least 3 inches in ... The scanned data capture three-dimensional (3-D) images that illustrate log ...

308

Biased estimation of forest log characteristics using intersect diameters  

Microsoft Academic Search

Logs are an important structural feature of forest ecosystems, and their abundance affects many resources and forest processes, including fire regimes, soil productivity, silviculture, carbon cycling, and wildlife habitat. Consequently, logs are often sampled to estimate their frequency, percent cover, volume, and weight. The line-intersect method (LIM) is one of the most widely used methods to obtain these estimates and

Lisa J. Bate; Torolf R. Torgersen; Michael J. Wisdom; Edward O. Garton

2009-01-01

309

Western Tight Gas Sands Advanced Logging Workshop Proceedings.  

National Technical Information Service (NTIS)

An advanced logging research program is one major aspect of the Western Tight Sands Program. Purpose of this workshop is to help BETC define critical logging needs for tight gas sands and to allow free interchange of ideas on all aspects of the current lo...

J. B. Jennings H. B. Carroll

1982-01-01

310

Effects of Compositional and Structural Variations on Log Responses in Igneous and Metamorphic Rocks  

NASA Astrophysics Data System (ADS)

Petrophysical in-situ data of several boreholes drilled igneous and metamorphic rocks of continental and oceanic basement were analyzed in order to characterize and classify the occurring rock types. Since physical properties of crystalline rocks are controlled by both, compositional and structural features, one objective of this study was to develop methods to detect and quantify matrix effects. The comparison of mineralogical and geochemical core data with wireline data reveal following systematic observations: (1) Mafic rocks (e.g. oceanic basalts, volcanic island basalts, gabbros and amphibolites) generally have low contents of radioactive minerals. This is in particular valid for mafic rocks from the upper and lower oceanic crust. Slight increases in gamma-ray are related to an enrichment in potassium due to seafloor alteration. In contrast to this uniform, mantle source controlled rocks, extrusives and re-sedimented material from ocean islands and large igneous provinces show a large scatter in gamma-ray responses as a result of their more complex evolution. Mafic rocks recovered from boreholes into continental crust, are characterized by high gamma-ray values, due to enrichment of thorium and uranium during regional metamorphism. In contrast to the mafic plutonic and metamorphic rocks, where the density and p-wave velocity is controlled by the mineralogical composition, the physical parameters of mafic volcanic rocks are strongly affected by fracturing and vesicularity. Density, p-wave velocity and electrical resistivity logs are significantly lowered depending on the degree of vesicularity and fracturing. (2) Acid to intermediate igneous rocks and orthogneisses are distinguishable from paragneisses by their log responses despite showing a similar geochemical composition. The main difference occurs for the relation of the gamma-ray log to the density and neutron porosity log. The gamma-ray in paragneisses is controlled by the amount of phyllosilicates, which is dependent on the initial input of pelitic material of the educt. This produces a typical log signature, which shows a positive correlation of the gamma-ray with the density and neutron porosity log. In contrast, the gamma-ray in igneous rocks and orthogneisses follows the magmatic differentiation trend with an increase of potassium-feldspar with rock acidity causing a negative correlation of the gamma-ray log with the density and the neutron porosity log. These relations were observed up to higher amphibolite facies conditions and hold true if metamorphic overprint took place in a more or less closed system. Based on these relations in physical rock properties classification diagrams for the crystalline rock types were established. They will help to separate matrix effects from structural properties and thus to improve the estimation of porosity from density, velocity and neutron porosity measurements.

Pechnig, R.; Bartetzko, A.; Delius, H.

2001-12-01

311

PREDICTING SOIL SORPTION COEFFICIENTS OF ORGANIC CHEMICALS USING A NEURAL NETWORK MODEL  

EPA Science Inventory

The soil/sediment adsorption partition coefficient normalized to organic carbon (Koc) is extensively used to assess the fate of organic chemicals in hazardous waste sites. Several attempts have been made to estimate the value of Koc from chemical structure ...

312

West Pembina Nisku reef log-core correlations  

SciTech Connect

A study was initiated to correlate log parameters and core data from West Pembina Nisku (D-2) Pinnacle reefs. The primary objective was to derive basic input data for making volumetric estimates of reserves and for providing initial input data for doing enhanced recovery model studies. A secondary objective was to determine if a set of log analysis parameters could be derived that would work universally in the many pinnacle reefs of the West Pembina area. The results of the study indicate that porosity log response in the West Pembina Nisku reefs deviates a fair amount from the standards used in log analysis chart books. A multilinear regression formula for determining porosity was derived which worked well for 18 wells studied, on which there was both log and core data. A brief description of the Nisku reef geology, a description of the methods used in doing the study, and a graphic presentation of the results are included.

McFadzean, T.B.

1983-01-01

313

Navjot's nightmare revisited: logging, agriculture, and biodiversity in Southeast Asia.  

PubMed

In 2004, Navjot Sodhi and colleagues warned that logging and agricultural conversion of Southeast Asia's forests were leading to a biodiversity disaster. We evaluate this prediction against subsequent research and conclude that most of the fauna of the region can persist in logged forests. Conversely, conversion of primary or logged forests to plantation crops, such as oil palm, causes tremendous biodiversity loss. This loss is exacerbated by increased fire frequency. Therefore, we conclude that preventing agricultural conversion of logged forests is essential to conserving the biodiversity of this region. Our analysis also suggests that, because Southeast Asian forests are tightly tied to global commodity markets, conservation payments commensurate with combined returns from logging and subsequent agricultural production may be required to secure long-term forest protection. PMID:23764258

Wilcove, David S; Giam, Xingli; Edwards, David P; Fisher, Brendan; Koh, Lian Pin

2013-06-11

314

Coal log pipeline research at the University of Missouri  

SciTech Connect

Project tasks: Perform the necessary testing and development to demonstrate that the amount of binder in coal logs can be reduced to 8% or lower to produce logs with adequate strength to eliminate breakage during pipeline transportation, under conditions experienced in long distance pipeline systems. Prior to conducting any testing and demonstration, grantee shall perform an information search and make full determination of all previous attempts to extrude or briquette coal, upon which the testing and demonstration shall be based. Perform the necessary development to demonstrate a small model of the most promising injection system for coal-logs, and test the logs produced from Task 1. Conduct economic analysis of coal-log pipeline, based upon the work to date. Refine and complete the economic model. Prepare a final report for DOE.

Liu, H.

1992-03-01

315

Financial Anti-Bubbles Log-Periodicity in Gold and Nikkei Collapses  

NASA Astrophysics Data System (ADS)

We propose that the herding behavior of traders leads not only to speculative bubbles with accelerating over-valuations of financial markets possibly followed by crashes, but also to "anti-bubbles" with decelerating market devaluations following all-time highs. For this, we propose a simple market dynamics model in which the demand decreases slowly with barriers that progressively quench in, leading to a power law decay of the market price characterized by decelerating log-periodic oscillations. We document this behavior of the Japanese Nikkei stock index from 1990 to present and of the gold future prices after 1980, both after their all-time highs. We perform simultaneously parametric and nonparametric analyses that are fully consistent with each other. We extend the parametric approach to the next order of perturbation, comparing the log-periodic fits with one, two and three log-frequencies, the latter providing a prediction for the general trend in the coming years. The nonparametric power spectrum analysis shows the existence of log-periodicity with high statistical significance, with a preferred scale ratio of ??3.5 for the Nikkei index and ??1.9 for the Gold future prices, comparable to the values obtained for speculative bubbles leading to crashes.

Johansen, A.; Sornette, D.

316

Experimental correlation between the p Ka value of sulfonphthaleins with the nature of the substituents groups  

NASA Astrophysics Data System (ADS)

This work presents the results obtained from a spectrophotometry study performed on some indicators of the sulfonphtaleins like phenol red (PR), thymol blue (TB), bromothymol blue (BTB), xylenol orange (XO) and methylthymol blue (MTB). During the first stage the acidity constants of some of the indicators were determined using the data from spectrophotometry, potentiometry and with the use of the software SQUAD. These were as follows: for the equilibrium 2H + BTB ? H 2BTB, log ?2 = 15.069 ± 0.046 and for H + BTB ? HBTB, log ?1 = 8.311 ± 0.044. For the XO and the MTB five values were calculated for each, namely, for MTB: log ?5 = 42.035, log ?4 = 38.567 ± 0.058, log ?3 = 32.257 ± 0.057, log ?2 = 23.785 ± 0.057, and log ?1 = 12.974 ± 0.045 while for XO: log ?5 = 40.120 ± 0.102, log ?4 = 35.158 ± 0.062, log ?3 = 29.102 ± 0.053, log ?2 = 21.237 ± 0.044, and log ?1 = 11.682 ± 0.044. During the second stage, a study was conducted on the effect of the substituents present in the indicators to determine the effect of different functional groups on the p Ka value corresponding to the last indicator's dissociation.

Balderas-Hernández, Patricia; Ramírez-Silva, María Teresa; Romero-Romo, Mario; Palomar-Pardavé, Manuel; Roa-Morales, Gabriela; Barrera-Diaz, Carlos; Rojas-Hernández, Alberto

2008-04-01

317

An {Omega}({radical}log log n) lower bound for routing in optical networks  

SciTech Connect

Optical communication is likely to significantly speed up parallel computation because the vast bandwidth of the optical medium can be divided to produce communication networks of very high degree. However, the problem of contention in high-degree networks makes the routing problem in these networks theoretically (and practically) difficult. In this paper we examine Valiant`s h-relation routing problem, which is a fundamental problem in the theory of parallel computing. The h-relation routing problem arises both in the direct implementation of specific parallel algorithms on distributed-memory machines and in the general simulation of shared memory models such as the PRAM on distributed-memory machines. In an h-relation routing problem each processor has up to h messages that it wishes to send to other processors and each processor is the destination of at most h messages. We present a lower bound for routing an h-relation (for any h > 1) on a complete optical network of size -n. Our lower bound applies to any randomized distributed algorithm for this task. Specifically, we show that the expected number of communication steps required to route an arbitrary h-relation is {Omega}(h + {radical}log log n). This is the first known lower bound for this problem which does not restrict the class of algorithms under consideration.

Goldberg, L.A. [Sandia National Labs., Albuquerque, NM (United States); Jerrum, M. [Edinburgh Univ. (United Kingdom). Dept. of Computer Science; MacKenzie, P.D. [Texas Univ., Austin, TX (United States). Dept. of Computer Sciences

1993-11-06

318

Prediction of the impact of logging activities on forest cover: a case-study in the east province of Cameroon.  

PubMed

The objective of this study was to test the value of the concept of the net commercial value of standing timber in predicting the impact of logging activities on forest-cover modifications. A study area was selected in the East province of Cameroon which contains major primary forests and which contributes strongly to national timber production. A Geographic Information System containing ecological and economic variables was used in combination with remote sensing data to define the net commercial value of standing timber in the East province. Taking account of the potential commercial value of standing timber improves our understanding of the spatial determinants of logging activities and of the resulting forest-cover modifications. The occurrence of logging-induced forest-cover modifications increases with the value of forest rent. In one of the study sites, half of the very high rent areas have already been logged. In that site, therefore, it is mostly the low rent or marginal forest areas that remain unlogged. This was not the case, however, throughout the study area as shown by the observations at another site. PMID:11400462

Mertens, B; Forni, E; Lambin, E F

2001-05-01

319

Extracting the Textual and Temporal Structure of Supercomputing Logs  

SciTech Connect

Supercomputers are prone to frequent faults that adversely affect their performance, reliability and functionality. System logs collected on these systems are a valuable resource of information about their operational status and health. However, their massive size, complexity, and lack of standard format makes it difficult to automatically extract information that can be used to improve system management. In this work we propose a novel method to succinctly represent the contents of supercomputing logs, by using textual clustering to automatically find the syntactic structures of log messages. This information is used to automatically classify messages into semantic groups via an online clustering algorithm. Further, we describe a methodology for using the temporal proximity between groups of log messages to identify correlated events in the system. We apply our proposed methods to two large, publicly available supercomputing logs and show that our technique features nearly perfect accuracy for online log-classification and extracts meaningful structural and temporal message patterns that can be used to improve the accuracy of other log analysis techniques.

Jain, S; Singh, I; Chandra, A; Zhang, Z; Bronevetsky, G

2009-05-26

320

A generalized approach for the interpretation of geophysical well logs in ground-water studies -- Theory and application  

SciTech Connect

Implementation of models for the simulation of groundwater flow and contaminant transport in aquifers requires subsurface characterization of the boundaries and hydraulic properties of the geological formations through which ground water flows. Quantitative analysis of geophysical logs in ground-water studies often involves at least as broad a range of applications and variation in lithology as is typically encountered in petroleum exploration, making such logs difficult to calibrate and complicating inversion problem formulation. At the same time, data inversion and analysis depend on inversion model formulation and refinement, so that log interpretation cannot be deferred to a geophysical log specialist unless active involvement with interpretation can be maintained by such an expert over the lifetime of the project. The authors propose a generalized log-interpretation procedure designed to guide hydrogeologists in the interpretation of geophysical logs, and in the integration of log data into ground-water models that may be systematically refined and improved in an iterative way. The procedure is designed to maximize the effective use of three primary contributions from geophysical logs: (1) The continuous depth scale of the measurements along the well bore; (2) The in situ measurement of lithologic properties and the correlation with hydraulic properties of the formations over a finite sample volume; and (3) Multiple independent measurements that can potentially be inverted for multiple physical or hydraulic properties of interest. The approach is formulated in the context of geophysical inversion theory, and is designed to be interfaced with surface geophysical soundings and conventional hydraulic testing. The procedures given in the generalized interpretation and inversion technique are based on both qualitative analysis designed to assist formulation of the interpretation model, and quantitative analysis used to assign numerical values to model parameters.

Paillet, F.L. [Geological Survey, Denver, CO (United States). Denver Federal Center; Crowder, R.E. [Colog, Inc., Golden, CO (United States)

1996-09-01

321

The conservation value of oil palm plantation estates, smallholdings and logged peat swamp forest for birds  

Microsoft Academic Search

The expansion of industrial oil palm cultivation threatens tropical biodiversity globally, especially in developing countries. Driven by plans to generate economic revenue, large-scale plantations are emerging in Southeast Asia, Africa and Brazilian Amazon. However, the ecological impacts of the sector are poorly studied with respect to oil palm management system, and recommended conservation measures are based on limited data. We

Badrul Azhar; David B. Lindenmayer; Jeff Wood; Joern Fischer; Adrian Manning; Chris McElhinny; Mohamed Zakaria

2011-01-01

322

The value of value congruence.  

PubMed

Research on value congruence has attempted to explain why value congruence leads to positive outcomes, but few of these explanations have been tested empirically. In this article, the authors develop and test a theoretical model that integrates 4 key explanations of value congruence effects, which are framed in terms of communication, predictability, interpersonal attraction, and trust. These constructs are used to explain the process by which value congruence relates to job satisfaction, organizational identification, and intent to stay in the organization, after taking psychological need fulfillment into account. Data from a heterogeneous sample of employees from 4 organizations indicate that the relationships that link individual and organizational values to outcomes are explained primarily by the trust that employees place in the organization and its members, followed by communication, and, to a lesser extent, interpersonal attraction. Polynomial regression analyses reveal that the relationships emanating from individual and organizational values often deviated from the idealized value congruence relationship that underlies previous theory and research. The authors' results also show that individual and organizational values exhibited small but significant relationships with job satisfaction and organizational identification that bypassed the mediators in their model, indicating that additional explanations of value congruence effects should be pursued in future research. PMID:19450005

Edwards, Jeffrey R; Cable, Daniel M

2009-05-01

323

Fluid-temperature logs for selected wells in eastern Washington  

SciTech Connect

This Open-File Report consists of fluid temperature logs compiled during studies of the geohydrology and low temperature geothermal resources of eastern Washington. The fluid temperature logs are divided into two groups. Part A consists of wells which are concentrated in the Moses Lake-Ritzville-Connell area. Full geophysical log suites for many of these wells are presented in Stoffel and Widness (1983) and discussed in Widness (1983, 1984). Part B consists of wells outside of the Moses Lake-Ritzville-Connell study area.

Stoffel, K.L.; Widness, S. (comps.)

1983-12-01

324

Geothermal well log interpretation state of the art. Final report  

SciTech Connect

An in-depth study of the state of the art in Geothermal Well Log Interpretation has been made encompassing case histories, technical papers, computerized literature searches, and actual processing of geothermal wells from New Mexico, Idaho, and California. A classification scheme of geothermal reservoir types was defined which distinguishes fluid phase and temperature, lithology, geologic province, pore geometry, salinity, and fluid chemistry. Major deficiencies of Geothermal Well Log Interpretation are defined and discussed with recommendations of possible solutions or research for solutions. The Geothermal Well Log Interpretation study and report has concentrated primarily on Western US reservoirs. Geopressured geothermal reservoirs are not considered.

Sanyal, S.K.; Wells, L.E.; Bickham, R.E.

1980-01-01

325

Wideband mm-wave log-periodic antennas  

Microsoft Academic Search

Wideband mm-wave end-fire and planar log-periodic antennas compatible with a recently developed surface micromachined process known as PolyStratatrade are discussed in this paper. Two embodiments of each log-periodic type are developed. Specifically, an instantaneous 2-110 GHz and a dual-band 18-50 GHz and 75-110 GHz planar log-periodic antennas with integrated rectangular micro-coaxial feeds\\/impedance transformers and VSWR < 2.5:1 are designed. An

Joseph Mruk; Zhou Hongyu; Manseok Uhm; Yuya Saito; Dejan Filipovic

2009-01-01

326

Project to transcribe old ship logs provides important weather data  

NASA Astrophysics Data System (ADS)

Kathy Wendolkowski is a citizen scientist. It's a term that Wendolkowski considers far too lofty for what she claims is simply a happy addiction that she and others have for transcribing old logs from naval ship and other vessels. They perform this task to glean the regularly recorded weather data from those logs for the benefit of science. For Wendolkowski, though, greater satisfaction comes from reading what the logs also reveal about the daily lives of the sailors as well as any accompanying historical drama.

Showstack, Randy

2012-11-01

327

Post-wildfire logging hinders regeneration and increases fire risk.  

PubMed

We present data from a study of early conifer regeneration and fuel loads after the 2002 Biscuit Fire, Oregon, USA, with and without postfire logging. Natural conifer regeneration was abundant after the high-severity fire. Postfire logging reduced median regeneration density by 71%, significantly increased downed woody fuels, and thus increased short-term fire risk. Additional reduction of fuels is necessary for effective mitigation of fire risk. Postfire logging can be counterproductive to the goals of forest regeneration and fuel reduction. PMID:16400111

Donato, D C; Fontaine, J B; Campbell, J L; Robinson, W D; Kauffman, J B; Law, B E

2006-01-05

328

Calibration of log and core saturation data: case history from San Ardo field  

SciTech Connect

A major problem in reservoir evaluation is determining saturations and monitoring changes during production. Many companies in the San Joaquin Valley use extensive coring to solve this problem. Modern lithologic and well-log analyses offer a means of calibrating log-derived saturations to core saturations, thus reducing the need for expensive coring. Such a study was performed on a well in the San Ardo field, a heavy oil accumulation in the Salinas basin, Monterey County, California. DIL, FDC-CNL, and EPT logs were used in conjunction with conventional core analysis, grain-density determinations, and several XRD and thin-section studies to derive mineralogy. The log analysis was performed using the commercially available PETROS computer program. An excellent fit was achieved between core and resistivity log-derived water saturations. The Archie equation variables, a, m, and n, were determined by a few iterations since the curves could be matched so easily, but special core-analysis technique would have been used if needed to find values for these parameters. The lithologic data showed that the sand was virtually clay free, thus eliminating the need for shale corrections. The deep-reading resistivity-derived Sw and the core saturations matched so closely that, apparently, the core had not undergone much flushing, if any. The EPT, a flushed-zone device, showed about 17% higher water saturations through the main steamflood zone than did the core and Archie saturations, which was interpreted to mean that the heated oil had been moved within 1 in. or so of the borehole wall. In other unflooded zones, the EPT saturation closely matched the other curves.

Olson, D.M.

1986-04-01

329

Silicone rubber passive samplers for measuring pore water and exchangeable concentrations of polycyclic aromatic hydrocarbons concentrations in sediments.  

PubMed

The use of a silicone rubber passive sampler for the assessment of the availability of lipophilic organic contaminants in sediments is described. The passive sampler accumulated polycyclic aromatic hydrocarbons (PAHs) from sediments with an equilibration time of 20days for most PAHs. The method was used to measure the free dissolved concentrations in pore water of 30 PAHs (parent and alkylated), their water exchangeable concentrations and sediment-water partition coefficients in field sediments from a Scottish sea loch that supports fish farming. Fluoranthene and pyrene dominated the PAH concentration composition in the pore waters. The water exchangeable concentration reflected the pyrogenic pollution pattern found in the sediments and indicated that a proportion of the PAHs were not available for exchange with the aqueous phase. Strong linear relationships between organic carbon normalised sediment-water partition coefficients (logKoc) and corresponding octanol-water partition coefficients of PAHs were obtained. The logKoc values obtained are on average, 0.6log units higher than literature values commonly used in sediment risk assessments, consequently direct measurements of logKoc in field sediments should be used to improve the reliability of risk assessments. PMID:23872250

Yates, Kyari; Pollard, Pat; Davies, Ian; Webster, Lynda; Moffat, Colin

2013-07-19

330

Quality measures for geostatistical prediction of log-normal soil properties.  

NASA Astrophysics Data System (ADS)

A signature of non-linear processes in the soil is the non-normal distribution of soil properties. A common non-normal distribution is the log-normal, in which the variable Z can be transformed to a variable with a normal distribution by Y = log e(Z). Log-normal variables are common in soil geochemistry and hydrology. It is standard practice in geostatistics to use the log-transformation for such variables before spatial modelling and prediction, and there are procedures to back-transform predictions of Y to the original scale of measurement Z. This is important because values on the original scale are commonly required either for scientific purposes or for practical applications such as the assessment of potential contaminant concentrations in soil. One of the strengths of geostatistics is that geostatistical prediction returns a prediction error variance. Furthermore, this variance can be computed before a survey is undertaken, for a range of possible different sampling networks, since it depends only on the disposition of sample sites, and the variogram model of spatial dependence. This allows the most efficient network to be selected: one which will provide estimates of sufficient precision (where the prediction error variances are within acceptable bounds) without over-sampling. In log-normal kriging the prediction error variance depends not only on the variogram and the sampling array, but also on the conditional mean value of the variable, which is not known until after sampling. This means that the usual pre-survey quality measures which can be computed to guide the planning of geostatistical surveys are not available for log-normal variables. Given that many critical variables, such as contaminant concentrations, are often log-normally distributed, this is a serious gap in the capablity of geostatistics to facilitate rational sampling design for environmental management and monitoring. In this paper I propose and demonstrate some quality measures that can be computed, pre-survey, for different sampling networks for log-normal variables. I propose measures that are suitable both for point kriging, when predictions are obtained for the same sample support as the observations, and for block kriging when the predictions are upscaled to a region, such as a management unit or a regular block. The quality measures are dimensionless prediction intervals, scaled relative to the unknown median value of the target conditional distribution. In the point kriging case the distribution of interest is the conditional distribution of the variable at the target location. In the block kriging case the distribution is that of the spatial median value over the block. These quality measures are illustrated in a case study on the spatial variability of some critical metals and metalloids in the soil of eastern England. Target values of the quality measures are defined in terms of the requirements that land managers or regulators may specify for uncertainty in final predictions, and the sampling effort required to meet these is computed.

Lark, R. M.

2012-04-01

331

Valuing Wildlands  

Treesearch

Environmental Risk Assessment and Management from a Landscape Perspective. ... The question is, of course, fundamental to economic models and modes of ... The value of wildlands is derived from human use of resources, as well as ...

332

An Effective Hash-Based Method for Generating Synthetic Well Log  

Microsoft Academic Search

Well log analysis is one of the costliest parts of petroleum fields. It has been realized that developing synthetic well logs can help analyze the reservoir properties in areas where some necessary logs are absent or incomplete, and then reduce costs of companies. During generating synthetic logs, logging time should be used sufficiently for predicting trends and filling some incomplete

Yi Du; Detang Lu; Daolun Li

2008-01-01

333

Long-Term Patterns in Leaf Breakdown in Streams in Response to Watershed Logging  

Microsoft Academic Search

The watershed of Big Hurricane Branch, Coweeta Hydrologic Laboratory, North Carolina, USA, was logged in 1976. We measured breakdown rates of experimental leaf packs in this second-order stream prior to logging, during logging, soon after logging, and 3 additional times since then. Leaf breakdown was slow just after logging, apparently due to leaf burial by sediments. Thereafter, leaf breakdown rates

E. F. Benfield; J. R. Webster; J. L. Tank; J. J. Hutchens

2001-01-01

334

Secure Audit Logs Server to support computer forensics in criminal investigations  

Microsoft Academic Search

Few people pay attention to the security of audit logs. The security of logs is based upon the security of the systems which the logs were kept in. We bring forward a system called Secure Audit Logs Server which adopts encryption and dynamic MAC to guarantee the integrity and dependability of the logs. This is important for obtaining effective evidence.

Liu Jiqiang; Han Zhen; Lan Zengwei

2002-01-01

335

Computation of distribution of minimum resolution for log-normal distribution of chromatographic peak heights.  

PubMed

General equations are derived for the distribution of minimum resolution between two chromatographic peaks, when peak heights in a multi-component chromatogram follow a continuous statistical distribution. The derivation draws on published theory by relating the area under the distribution of minimum resolution to the area under the distribution of the ratio of peak heights, which in turn is derived from the peak-height distribution. Two procedures are proposed for the equations' numerical solution. The procedures are applied to the log-normal distribution, which recently was reported to describe the distribution of component concentrations in three complex natural mixtures. For published statistical parameters of these mixtures, the distribution of minimum resolution is similar to that for the commonly assumed exponential distribution of peak heights used in statistical-overlap theory. However, these two distributions of minimum resolution can differ markedly, depending on the scale parameter of the log-normal distribution. Theory for the computation of the distribution of minimum resolution is extended to other cases of interest. With the log-normal distribution of peak heights as an example, the distribution of minimum resolution is computed when small peaks are lost due to noise or detection limits, and when the height of at least one peak is less than an upper limit. The distribution of minimum resolution shifts slightly to lower resolution values in the first case and to markedly larger resolution values in the second one. The theory and numerical procedure are confirmed by Monte Carlo simulation. PMID:21939978

Davis, Joe M

2011-09-03

336

Estimating organic maturity from well logs, Upper Cretaceous Austin Chalk, Texas Gulf coast  

SciTech Connect

The Austin Chalk is both a source rock for oil and a fractured reservoir, and the evaluation of its organic maturity from well logs could be an aid to exploration and production. Geochemical measurements have shown three zones of organic maturity for source materials: (1) an immature zone to depths of 6,000 ft, (2) a peak-generation and accumulation zone from 6,000 to 6,500 ft, and (3) a mature, expulsion and migration zone below 6,500 ft. The response of common well logs identifies these zones. True resistivity (R{sub t}) is low in the immature zone, increases to a maximum in the peak-generation zone, and decreases to intermediate values in the expulsion zone. Density and neutron porosities are different in the immature zone but are nearly equal in the peak generation and expulsion zones. Correlations with conventional core analyses indicate that R{sub t} values between 9 and 40 ohm-m in the expulsion zone reflect a moveable oil saturation of 10 to 20% in the rock matrix. The moveable saturation provides oil from the matrix to fractures and is essential for sustained oil production. Therefore, the evaluation of moveable oil from well logs could be important in exploration.

Hines, G.A.; Berg, R.R. (Texas A and M Univ., College Station (USA))

1990-09-01

337

Identification of Competencies for Forest Production and Logging Occupations  

ERIC Educational Resources Information Center

|The author presents the research methodology and a summary of the findings from a study to investigate the competencies required for entrance into the occupations of forestry aide, logging skidder operator, and wood producer. (MF)|

McCully, James S.

1977-01-01

338

14. VIEW OF LOG BRIDGE (LATER SUPERSEDED BY THE WIREROPE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. VIEW OF LOG BRIDGE (LATER SUPERSEDED BY THE WIRE-ROPE SUSPENSION BRIDGE), SHOWING OVERHANG WHERE ROCK WAS BLASTED OUT, LOOKING SOUTHWEST - Goat Trail Mining Road, Highway 20, 1.5 miles North of Newhalem, Newhalem, Whatcom County, WA

339

13. VIEW OF LOG BRIDGE (LATER SUPERSEDED BY THE WIREROPE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. VIEW OF LOG BRIDGE (LATER SUPERSEDED BY THE WIRE-ROPE SUSPENSION BRIDGE), SHOWING OVERHANG WHERE ROCK WAS BLASTED OUT, LOOKING NORTHEAST - Goat Trail Mining Road, Highway 20, 1.5 miles North of Newhalem, Newhalem, Whatcom County, WA

340

15. MEREDITH AVENUE, VIEW WITH LOG RAIL AND BARN. PERHAPS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. MEREDITH AVENUE, VIEW WITH LOG RAIL AND BARN. PERHAPS THE LAST REMAINING EXAMPLE OF CCC BUILT "RUSTIC STYLE" GUARD RAIL IN PARK. VIEW NE. - Gettysburg National Military Park Tour Roads, Gettysburg, Adams County, PA

341

Logging while fishing technique results in substantial savings  

SciTech Connect

During wireline logging operations, tools occasionally become stuck in the borehole and require fishing. A typical fishing job can take anywhere from 1{1/2}--4 days. In the Gulf of Mexico, a fishing job can easily cost between $100,000 and $500,000. These costs result from nonproductive time during the fishing trip, associated wiper trip and relogging the well. Logging while fishing (LWF) technology is a patented system capable of retrieving a stuck fish and completing the logging run during the same pipe descent. Completing logging operations using LWF method saves time and money. The technique also provides well information where data may not otherwise have been obtained. Other benefits include reduced fishing time and an increased level of safety.

Tollefsen, E.; Everett, M.

1996-12-01

342

11. Detail of log stamp on ends of plank, near ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. Detail of log stamp on ends of plank, near the Minnesota end of the bridge - Enloe Bridge No. 90021, Spanning Red River of North between Minnesota & North Dakota on County State Aid Highway 28, Wolverton, Wilkin County, MN

343

Fluid-Rock Characterization and Interactions in NMR Well Logging.  

National Technical Information Service (NTIS)

The objective is to characterize the fluid properties and fluid-rock interactions that are needed for formation evaluation by nuclear magnetic resonance (NMR) well logging. This project is a partnership between Professor George J. Hirasaki at Rice Univers...

G. J. Hirasaki K. K. Mohanty

2002-01-01

344

Heuristic search method for optimal zonation of well logs  

SciTech Connect

Optimal zonation of well-log data, that is, determining an optimal number of major segments such as waveforms in a log, may be achieved by employing a criterion of minimum variance (within a segment) and a heuristic search of potential boundary (link) points of digitized log data. This new method is based on an algorithm originally devised by D.M. Hawkins and D.F. Merriam in 1973. Their method can be improved by introducing a heuristic search procedure, thereby decreasing computer time by 7- to 50-fold, depending on the number of data points and configuration of the logs. Time saving is proportional to the size of the data set. Three examples - one hypothetical and two real-are used to illustrate the modification of the Hawkins and Merriam algorithm.

Chen, H.C.; Fang, J.H.

1986-07-01

345

51. View of Caroline Dormon's log house looking from the ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

51. View of Caroline Dormon's log house looking from the southeast (similar to HALS no. LA-1-18) - Briarwood: The Caroline Dormon Nature Preserve, 216 Caroline Dormon Road, Saline, Bienville Parish, LA

346

50. View of Caroline Dormon's log house looking from the ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

50. View of Caroline Dormon's log house looking from the southwest (view similar to HALS no. LA-1-21) - Briarwood: The Caroline Dormon Nature Preserve, 216 Caroline Dormon Road, Saline, Bienville Parish, LA

347

16. DETAIL IN CELLAR, SOUTH SIDE, SHOWING VERTICAL OAK LOGS ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. DETAIL IN CELLAR, SOUTH SIDE, SHOWING VERTICAL OAK LOGS GOING INTO THE GROUND AND SHORT RUBBLE STONE PIERS SUPPORTING FLOOR BEAMS (POTEAUX EN TERRE CONSTRUCTION) - Amoureaux House, St. Mary's Road, Sainte Genevieve, Ste. Genevieve County, MO

348

Formation evaluation: benefits of downhole logging while drilling  

SciTech Connect

The development of new downhole measurement systems, coupled with mud-pulse telemetry techniques, allows real time surface evaluation of downhole parameters while drilling. Currently available systems, such as Exploration Logging's DLWD tool, combine formation resistivity and natural gamma ray sensors with directional survey and other measurements. These parameters aid formation evaluation, pressure evaluation, well-bore positioning, and drilling efficiency. For real time applications, such as correlation and bed identification, a DLWD log can be treated as a conventional wireline log. For further evaluation, the interpretation of DLWD data requires an understanding of the differences in the design of MWD tools compared to conventional wireline tools, as well as include physical size, logging speed, borehole effects, invasion, etc. The benefits of real time subsurface data enhance other geologic and engineering data acquisition systems in formation evaluation, pressure evaluation, and well planning.

Turvill, J.A.; Troy, G.W.

1983-03-01

349

A proven record in changing attitudes about MWD logs  

SciTech Connect

Measurement while drilling (MWD) logs for quantitative reservoir characterization were evaluated during drilling of Gulf of Mexico flexure trend projects, Kilauea (Green Canyon Blocks 6 and 50) and Tick (Garden Banks Block 189). Comparisons confirmed that MWD can be used as an accurate replacement for wireline logging when borehole size is not a limiting factor. Texaco MWD experience evolved from last resort' to primary formation evaluation logging, which resulted in rigtime and associated cost savings. Difficult wells are now drilled and evaluated with confidence, geopressure is safely monitored, conventional core interval tops are selected, and geologic interpretations and operational decisions are made before wells TD. This paper reviews the performance, accuracy, and limitations of the MWD systems and compares the results to standard geophysical well logging techniques. Four case histories are presented.

Cantrell, L.; Paxson, K.B.; Keyser, W.L.; Ball, S.

1993-07-01

350

Well logging and completion technology for horizontal wellbores  

SciTech Connect

In highly deviated and, particularly, horizontal wellbores, special hardware systems guide, push, and/or pump the logging instrument assembly toward the bottom, i.e., the end of the wellbore, and to log the interval of interest. The present paper discusses basic pipe-conveyed logging (PCL) systems and the coiled-tubing-conveyed (CTC) system for completion and perforating applications in horizontal well bores, which already have proven successful in Europe, the US, and Canada. Open- and cased-hole field applications, with special emphasis on the Cretaceous Austin Chalk in Texas and the Bakken Shale in Wyoming, will illustrate today's technology and review advantages and possible constraints of these well logging and completion techniques.

Fertl, W.H. (Atlas Wireline Services, Houston, TX (USA))

1990-09-01

351

Measuring ecological impacts from logging in natural forests of the ...  

Treesearch

Despite several improvements in remote sensing technologies focused on ... The first assessment is conducted through a simple evaluation of future-crop trees ... in the forest because poor felling caused logs to split and lose merchantability; ...

352

13. DETAIL SHOWING EXPOSED VERTICAL LOG CONSTRUCTION WITH MEASURING TAPE, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. DETAIL SHOWING EXPOSED VERTICAL LOG CONSTRUCTION WITH MEASURING TAPE, WEST ROOM AT REAR OF HOUSE, FIRST FLOOR - Pierre Delassus DeLuziereHouse, U.S. Route 61, Sainte Genevieve, Ste. Genevieve County, MO

353

Symposium on high-temperature well-logging instrumentation  

SciTech Connect

The symposium contains papers about developments in borehole logging instrumentation that can withstand downhole temperatures in excess of 300/sup 0/C and pressures greater than 103 MPa. Separate abstracts have been prepared for individual papers. (ACR)

Dennis, B.R. (comp.)

1986-06-01

354

Combined Log Inventory and Process Simulation Models for the ...  

Treesearch

Contact Us · Research & Development ... Source: Proceedings, 23rd CIRP International Seminar on Manufacturing Systems. 8pp. ... Combined Log Inventory and Process Simulation Models for the Planning and Control of Sawmill Operations.

355

Safety Information Profile: Chainsaw Operations in the Logging Industry.  

National Technical Information Service (NTIS)

A safety information profile is presented for chainsaw operations in the logging industry (Standard Industrial Classification 241). Felling and bucking procedures are described. Potential safety and health hazards are reviewed, including cuts from the cha...

D. B. Hunt

1979-01-01

356

Some Environmental Effects of Cable Logging in Appalachian Forests.  

National Technical Information Service (NTIS)

The forestry literature was reviewed for reports concerning effects of wood products harvest on forest soil, water, residual stands, wildlife, and visual appeal. In all cases, cable logging caused less unwanted effect on all of these resources than did ot...

J. H. Patric

1980-01-01

357

Biased estimation of forest log characteristics using intersect diameters  

Treesearch

Description: Logs are an important structural feature of forest ecosystems, and their abundance affects many resources and forest processes, including fire regimes, soil productivity, silviculture, carbon cycling, and wildlife habitat.

358

Log-ratio circuit for beam position monitoring  

SciTech Connect

The logarithmic ratio of the signal amplitudes from beam-position probe-electrodes provides a normalized real-time analog signal that is more linear in beam displacement than other signal-processing techniques for circular cross-section, beam-position monitors. This paper describes work being done to develop a log-ratio circuit using an inexpensive, commercially available, logarithmic-response, integrated-circuit rf-amplifier. The circuit uses two amplifiers in a log (A) {minus} log (B) = log (A/B) configuration to provide the logarithmic ratio of the two rf input signals from the probe. The output is a real-time analog signal proportional to beam displacement. 4 refs., 7 figs.

Wells, F.D.; Gilpatrick, J.D.; Shafer, R.E.; Shurter, R.B.

1991-01-01

359

Interpretation of Core and Well Log Physical Property Data From Drill Hole UPH-3, Stephenson County, Illinois  

Microsoft Academic Search

Laboratory and well log physical property measurements show variations in the mineralogy with depth in UPH-3. Gamma ray values generally decrease with depth in the drill hole, corresponding to a decrease in the felsic mineral components of the granite. Correspondingly, an increase with depth in mafic minerals in the granite is indicated by the magnetic susceptibility and gamma ray measurements.

Jeffrey J. Daniels; Gary R. Olhoeft; James H. Scott

1983-01-01

360

Interpretation of core and well log physical property data from drill hole UPH-3, Stephenson County, Illinois  

Microsoft Academic Search

Laboratory and well log physical property measurements show variations in the mineralogy with depth in UPH-3. Gamma ray values generally decrease with depth in the drill hole, corresponding to a decrease in the felsic mineral components of the granite. Correspondingly, an increase with depth in mafic minerals in the granite is indicated by the magnetic susceptibility and gamma ray measurements.

Jeffrey J. Daniels; Gary R. Olhoeft; James H. Scott

1983-01-01

361

Trees and logs important to wildlife in the interior Columbia River basin. Forest Service general technical report  

Microsoft Academic Search

This publication provides qualitative and quantitative information on five distinct structures: living trees with decayed parts, trees with hollow chambers, trees with brooms, dead trees, and logs. Information is provided on the value of these structures to wildlife, the decay or infection processes involved in the information of these structures, and the principles to consider for selecting the best structures

E. L. Bull; C. G. Parks; T. R. Torgersen

1997-01-01

362

Web log mining based on improved FCM clustering algorithm  

NASA Astrophysics Data System (ADS)

In view of more iterative times, longer convergence time and lower accuracy of Fuzzy C-Means (FCM) clustering algorithm, an improved FCM (IFCM) clustering algorithm is put forward. After data preprocessing of web log, fuzzy clustering to the web log data is adopted with the help of IFCM clustering algorithm. It can provide foundation and help for the subsequent web page optimization and personalization services.

Wang, Zhijun; Zhou, Runjing

2010-08-01

363

Fluid-Rock Characterization and Interactions in NMR Well Logging  

SciTech Connect

The objective of this project was to characterize the fluid properties and fluid-rock interactions that are needed for formation evaluation by NMR well logging. The advances made in the understanding of NMR fluid properties are summarized in a chapter written for an AAPG book on NMR well logging. This includes live oils, viscous oils, natural gas mixtures, and the relation between relaxation time and diffusivity.

Hirasaki, George J.; Mohanty, Kishore K.

2003-02-10

364

Maximum entropy inversion of induction-log data  

SciTech Connect

This paper describes the development and application of some new algorithms based on the maximum entropy method (MEM) for inverting (i.e., deconvolving) induction-log data. The MEM has earned a reputation in many physical science fields as a technique that provides robust and accurate reconstructions of instrumentally blurred data. Dyos recently applied a MEM algorithm to the inversion of synthetic deep-induction-log data. This paper develops some new MEM algorithms overcome some of the limitations of previous inversion methods and inverse-deconvolution-filter techniques. This paper examines two different MEM algorithms. The first algorithm is based on a functional used to study MEM inversions of synthetic data with a Doll approximation forward model. A second, more efficient MEM algorithm, based on a new Lagrangian functional, is used with an exact forward model to study the inversion of a field log and some model formations. Use of an exact forward model is essential in obtaining accurate and high-resolution MEM inversions in the presence of skin and shoulder effects. The MEM inversions of model data and field logs exhibit vertical resolution, accuracy, and stability that exceed those obtainable with state-of-the-art linear inverse filters. An example of the MEM inversion of a field log in a formation with numerous high-contrast thin beds is discussed and compared with the spherically focused log (SFL{sup SM}) and the deep enhanced-resolution Phasor-(IDER{sup SM}) processed log. The MEM inversion exhibits resolution comparable to that of the SFL. It is shown that, as a byproduct, the MEM provides synthetic logs that serve as a self-consistency check on both the quality of entered data and the validity of the R{sub 1} profile obtained from inversion.

Freedman, R. (Schlumberger Well Services, Houston, TX (United States)); Minerbo, G.N. (Schlumberger-Doll Research Center, Ridgefield, CT (United States))

1991-06-01

365

Fluid-Rock Characterization and Interactions in NMR Well Logging  

SciTech Connect

The objective of this project was to characterize the fluid properties and fluid-rock interactions which are needed for formation evaluation by NMR well logging. NMR well logging is finding wide use in formation evaluation. The formation parameters commonly estimated were porosity, permeability, and capillary bound water. Special cases include estimation of oil viscosity, residual oil saturation, location of oil/water contact, and interpretation on whether the hydrocarbon is oil or gas.

Hirasaki, George J.; Mohanty, Kishore K.

2003-02-10

366

On Q(H log H) Scaling of Network Delays  

Microsoft Academic Search

A recent result in network calculus theory provided statistical delay bounds for exponentially bounded traffic that grow as O(H logH) with the number of nodes on the network path.1 In this paper we establish the corresponding lower bound which shows that for such such types of traffic, typical end-to- end delays can indeed grow as ?( H logH). The lower

Almut Burchard; Jörg Liebeherr; Florin Ciucu

2007-01-01

367

AL-log: Integrating Datalog and Description Logics  

Microsoft Academic Search

We present an integrated system for knowledge representation, calledAL-log, based on description logics and the deductive database language Datalog. AL-log embodies two subsystems, called structural and relational. The former allows for the definition of structural knowledge about classes of interest (concepts) and membership relation between objects and classes. The latter allows for the definition of relational knowledge about objects described

Francesco M. Donini; Maurizio Lenzerini; Daniele Nardi; Andrea Schaerf

1998-01-01

368

Application of multipole array sonic logging to acid hydralic fracturing  

Microsoft Academic Search

Multipole array sonic logging tools have widely been employed in Chinese oilfields in recent years. We have developed a software\\u000a package for rock mechanical analysis with multipole array sonic logs. This advanced data processing method and software have\\u000a been applied to the Tahe oilfield in Northern West China to provide guidance to acid hydraulic fracturing design and evaluation.\\u000a In this

Guo Tao; Kun Gao; Bing Wang; Yong Ma

2007-01-01

369

WebLogExpert Lite 3.6  

NSDL National Science Digital Library

For those users with websites, this little application will prove to be quite useful. Utilizing this latest version of WebLogExpert Lite, users will be able to review specific statistics about visitors to their site, including activities such as file access, error reports, and the like. The program also can generate reports on such activities that include both tables and charts. This version of WebLogExpert Lite is compatible with all computers running Windows 95 and newer.

2005-01-01

370

Log-Truck Scheduling with a Tabu Search Strategy  

Microsoft Academic Search

The Austrian forest sector has experienced extensive development in recent years. In 2003, approximately 27.9 million cubic\\u000a meters of logs were processed in Austria. In order to enable a stable supply, an efficient and economical operation for round\\u000a timber transport is necessary. In this paper, we present a Tabu Search based solution method for log-truck scheduling. A fleet\\u000a of m

Manfred Gronalt; Patrick Hirsch

371

A universal generator for discrete log-concave distributions  

Microsoft Academic Search

: We give an algorithm that can be used to sample from any discrete log-concave distribution(e.g. the binomial and hypergeometric distributions). It is based on rejection from a discrete dominatingdistribution that consists of parts of the geometric distribution. The algorithm is uniformly fast for alldiscrete log-concave distributions and not much slower than algorithms designed for a single distribution.AMS Subject Classification:

Wolfgang Hörmann

1994-01-01

372

Detection and monitoring of chlorinated solvent contamination by thermal neutron logging  

SciTech Connect

Thermal neutron logging is used to determine water content by measuring the elastic scattering due to hydrogen present in rocks and soils. The response of a thermal neutron device is also affected by the radiative capture of thermal neutrons by all elements. Chlorine has a large capture cross section in comparison to other elements usually found in aquifers; therefore, theory predicts that thermal neutron devices should respond to the presence of chlorinated solvents. Thermal neutron logging performed during a controlled release of perchloroethylene (PCE) confirmed that these methods can be used successfully to detect and monitor chlorinated solvents in the subsurface. To quantify the field results, a series of laboratory tests assessed the response of a neutron moisture probe used in the field experiments. These tests show that this device is very sensitive to the presence of chlorine and provide a basis for converting its response into an apparent PCE saturation. These saturation values compare favorably with PCE saturations obtained from core samples.

Endres, A.L.; Greenhouse, J.P. [Univ. of Waterloo, Ontario (Canada)

1996-03-01

373

New hole logging system tested for UK coal exploration  

SciTech Connect

Robertson Research Engineering Services was approached to look into the possibility of logging coal measure deposits for open pit coal exploration. Due to the development of a parallel-sided drill rod, it has now become possible to run geophysical logs through the rod. This, in fact, means that the need to pull the drill stem and to insert casing is avoided and much time, effort, and money may be saved. Thus, the rapid logging of coal boreholes using Robertson Research's gamma gamma density tool is now possible. Initial trials took place in Scotland to establish the principle that the equipment could log density and natural gamma satisfactorily through the drill rod. The short period of trials was successful and analysis of the results is being undertaken before starting a more vigorous program of development and trials to produce equipment to the specifications demanded by the National Coal Board, with particular reference to the operation of the equipment by the drilling company. In addition to gamma and density logging through the drill stem, gamma and laterologging have been carried out in open hole. The laterolog is particularly useful for the resolution of thin coal seams, which have a high electrical resistance. An additional and attractive advantage of the Wellog density logging system used in drill stem is that gamma radioactive sources are very small and are much less likely to be lost down the borehole.

Not Available

1980-09-01

374

Latent log-linear models for handwritten digit classification.  

PubMed

We present latent log-linear models, an extension of log-linear models incorporating latent variables, and we propose two applications thereof: log-linear mixture models and image deformation-aware log-linear models. The resulting models are fully discriminative, can be trained efficiently, and the model complexity can be controlled. Log-linear mixture models offer additional flexibility within the log-linear modeling framework. Unlike previous approaches, the image deformation-aware model directly considers image deformations and allows for a discriminative training of the deformation parameters. Both are trained using alternating optimization. For certain variants, convergence to a stationary point is guaranteed and, in practice, even variants without this guarantee converge and find models that perform well. We tune the methods on the USPS data set and evaluate on the MNIST data set, demonstrating the generalization capabilities of our proposed models. Our models, although using significantly fewer parameters, are able to obtain competitive results with models proposed in the literature. PMID:22064798

Deselaers, Thomas; Gass, Tobias; Heigold, Georg; Ney, Hermann

2012-06-01

375

Effects of Hydrothermal Alteration on In-situ Physical Properties in an Active Hydrothermal Vent Field - First Results of log Interpretation in ODP Hole 1189B  

NASA Astrophysics Data System (ADS)

For the first time in the history of the Ocean Drilling Program (ODP), Leg 193 drilled into an active hydrothermal vent field associated with felsic magmatism at a convergent plate margin. The main scientific objectives were to study the subsurface volcanic architecture of the Pual ridge, delineate the structural and hydrologic characteristics of the PACMANUS active hydrothermal system, and understand the mineralization and alteration patterns associated with vigorous high temperature fluid flow. Due to low core recovery, downhole logs provide the only continuous records of in-situ physical properties with depth hence the logs are of prime importance for achieving the scientific objectives of the leg. Downhole and core measurements from three holes located in the high temperature Roman Ruins hydrothermal field (Site 1189) show intense hydrothermal alteration of dacites and rhyodacites and evidence of a mineralized stockwork zone. Downhole measurements from Hole 1189B show characteristic cyclic trends with electrical resistivity logs decreasing upwards. The upper parts of these cycles are characterized by increasing values of the photoelectric factor log, an indicator for the composition of the formation and slightly increased density values. The trends correlate with an increase in fracturing/brecciation observed in the electrical images of the FMS (Formation MicroScanner). However, higher values of density and photoelectric factor indicate an enrichment of heavier minerals in the upper parts of the cycles. Spectral gamma ray logs do not correlate with the cyclic variations in the resistivity logs. Uranium, a mobile element often used as indicator for alteration, gives a large contribution to the total gamma ray spectrum. Thus two different assemblages of logs may be used as indicator for alteration/mineralization in Hole 1189B. No correlation exists between the cyclic trends and the variations in the spectral gamma ray logs. This indicates that different alteration processes may be responsible for the cyclic trends and for the variations in the uranium log, respectively.

Bartetzko, A.; Iturrino, G. J.

2001-12-01

376

Crop Values  

NSDL National Science Digital Library

While economic data on crop values are strictly commercial/ agricultural summaries, they can be useful as surrogate indices of land use/ cover change, or in estimating food subsidies (e.g. waste grain) for wildlife. Posted by the US Department of Agriculture (USDA) Economics and Statistics System at Cornell University, the site contains the "annual marketing year average prices and value of production of principal crops". Principal crops include barley (all, feed, and malting), hay, oats, rye, wheat (all, winter, durum, and other spring), upland and American-pima cotton and cottonseed, corn, dry beans, flaxseed, peanuts, sorghum, soybeans, sunflowers, and rice. These data are provided by the National Agricultural Statistics Service (USDA).

2005-12-07

377

Crop Values  

NSDL National Science Digital Library

While economic data on crop values are strictly commercial/ agricultural summaries, they can be useful as surrogate indices of land use/ cover change, or in estimating food subsidies (e.g. waste grain) for wildlife. Posted by the US Department of Agriculture (USDA) Economics and Statistics System at Cornell University, the site contains the "annual marketing year average prices and value of production of principal crops". Principal crops include barley (all, feed, and malting), hay, oats, rye, wheat (all, winter, durum, and other spring), upland and American-pima cotton and cottonseed, corn, dry beans, flaxseed, peanuts, sorghum, soybeans, sunflowers, and rice. These data are provided by the National Agricultural Statistics Service (USDA).

378

40 CFR 429.110 - Applicability; description of the log washing subcategory.  

Code of Federal Regulations, 2013 CFR

... false Applicability; description of the log washing subcategory...429.110 Applicability; description of the log washing subcategory...subpart applies to discharges to waters of the United States and...log washing process in which water under pressure is...

2013-07-01

379

49 CFR 393.116 - What are the rules for securing logs?  

Code of Federal Regulations, 2010 CFR

...loaded. (b) Components of a securement system. (1) Logs must be transported on a vehicle designed...one-sixth the weight of the stack of logs. (c) Use of securement system. (1) Logs must be solidly packed, and the...

2009-10-01

380

49 CFR 393.116 - What are the rules for securing logs?  

Code of Federal Regulations, 2010 CFR

...loaded. (b) Components of a securement system. (1) Logs must be transported on a vehicle designed...one-sixth the weight of the stack of logs. (c) Use of securement system. (1) Logs must be solidly packed, and the...

2010-10-01

381

Study of Log Raft Steering Sweeps Recovered from the Current River, Ripley County, Missouri.  

National Technical Information Service (NTIS)

Log rafting represents a rich heritage of the people along the Current River. The ancestors of most longterm residents residing in the valley were in some way involved in the logging industry and many specifically with log rafting. Significant ethnographi...

J. E. Price

1991-01-01

382

16. INTERPRETATION OF SITE 948 LOGGING-WHILE-DRILLING DATA: MINERALOGICAL INVERSION OF LOG DATA CONSTRAINED BY SAMPLE ANALYSES 1  

Microsoft Academic Search

This study is an original application of the log inversion methods on logging-while-drilling (LWD) measurements to clay min- eral estimation in an unusual geologic setting: the Barbados accretionary prism. LWD was used for the first time by the Ocean Drilling Program during Leg 156 at Sites 947 (Hole 947A) and 948 (Hole 948A). At Site 948 the décollement zone was

María José Jurado; Belén Alonso

383

Modeling and interpretation of Q logs in carbonate rock using a double porosity model and well logs  

Microsoft Academic Search

Attenuation data extracted from full waveform sonic logs is sensitive to vuggy and matrix porosities in a carbonate aquifer. This is consistent with the synthetic attenuation (1\\/Q) as a function of depth at the borehole-sonic source-peak frequency of 10 kHz. We use velocity and densities versus porosity relationships based on core and well log data to determine the matrix, secondary,

Jorge O. Parra; Chris L. Hackert

2006-01-01

384

Modeling and interpretation of Q logs in carbonate rock using a double porosity model and well logs  

Microsoft Academic Search

Attenuation data extracted from full waveform sonic logs is sensitive to vuggy and matrix porosities in a carbonate aquifer. This is consistent with the synthetic attenuation (1 \\/ Q) as a function of depth at the borehole-sonic source-peak frequency of 10 kHz. We use velocity and densities versus porosity relationships based on core and well log data to determine the

Jorge O. Parra; Chris L. Hackert

2006-01-01

385

Ruin Value  

Microsoft Academic Search

In this article I consider Albert Speer’s theory of ruin value through a discussion of the work of two Weimar theorists of ruination, Ernst Jünger and Walter Benjamin. The first section of the article relates Speer’s original theory of ruins to Nazi ideology. After this consideration of the Nazi obsession with ruination, the second division of the article explores the

Mark Featherstone

2005-01-01

386

Place Value  

NSDL National Science Digital Library

The answers to these FAQ from the Teacher2Teacher service at The Math Forum @ Drexel contain many suggestions for providing students with practice on using place value skills. They include ideas contributed by T2T Associates and teacher participants. There are links to Ask Dr. Math resources, children's literature connections, and outside websites with related resources.

Math Forum, Teacher2Teacher FAQ; The Math Forum @ Drexel

2000-01-01

387

Value Added  

ERIC Educational Resources Information Center

|This article profiles retiring values teacher Gene Doxey and describes his foundational contributions to the students of California's Ramona Unified School District. Every one of the Ramona Unified School District's 7,200 students is eventually funneled through Doxey's Contemporary Issues class, a required rite of passage between elementary…

Welch, Matt

2004-01-01

388

Utilizing magnetic resonance imaging logs, openhole logs, and sidewall core analyses to evaluate shaly sands for water-free production  

SciTech Connect

Nuclear magnetic resonance (NMR) logging using the new C Series Magnetic Resonance Imaging Log (MRIL) system is rapidly enhancing formation evaluation throughout the industry. By measuring irreducible water saturations, permeabilities, and effective porosities, MRIL data can help petrophysicists evaluate low-resistivity pays. In these environments, conventional openhole logs may not define all of the pay intervals. The MRIL system can also reduce the number of unnecessary completions in zones of potentially high water cut. MRIL tool theory and log presentations used with conventional logs and sidewall cores are presented along with field examples. Scanning electron microscope (SEM) analysis shows good correlation of varying grain size in sandstones with the T2 distribution and bulk volume irreducible water determined from the MRIL measurements. Analysis of each new well drilled in the study area shows how water-free production zones were defined. Because the MRIL data were not recorded on one of the wells, predictions from the conventional logs and the MRIL data collected on the other two wells were used to estimate productive zones in the first well. Discussion of additional formation characteristics, completion procedures, actual production, and predicted producibility of the shaly sands is presented. Integrated methodologies resulted in the perforation of 3 new wells for a gross initial potential of 690 BOPD and 0 BWPD.

Taylor, D.A.; Morganti, J.K.; White, H.J. (Oryx Energy Co., Dallas, TX (United States)); Noblett, B.R. (Western Atlas Logging Services, Dallas, TX (United States)) (and others)

1996-01-01

389

Perfluorinated compounds in Haihe River and Dagu Drainage Canal in Tianjin, China.  

PubMed

In this study, nine perfluorinated compounds (PFCs) were investigated in water and sediment of Haihe River (HR) and Dagu Drainage Canal (DDC), Tianjin, China. The total PFCs in water samples from DDC (40-174 ngL(-1)) was much greater than those from HR (12-74 ngL(-1)). PFC contamination was severe at lower reaches of HR due to industry activities, while high PFCs were found in the middle of DDC due to the effluents from wastewater treatment plants. Perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) were the predominant PFCs in aqueous phase. The total PFCs in sediments from DDC (1.6-7.7 ngg(-1) dry weight) were lower as compared to HR (7.1-16 ngg(-1)), maybe due to the dredging of sediment in DDC conducted recently. PFOS was the major PFC in HR sediments followed by PFOA; while PFHxA was the major PFC in DDC sediments. Organic carbon calibrated sediment-water distribution coefficients (K(OC)) were calculated for HR. The Log K(OC) ranged from 3.3 to 4.4 for C7-C11 perfluorinated carboxylic acids, increasing by 0.1-0.6 log units with each additional CF(2) moiety. The log K(OC) for 8:2 fluorotelomer unsaturated acid was reported for the first time with a mean value of 4.0. The log Koc of PFOS was higher than perfluoronanoic acid by 0.8 log units. PMID:21524781

Li, Fasong; Sun, Hongwen; Hao, Zhineng; He, Na; Zhao, Lijie; Zhang, Tao; Sun, Tiehang

2011-04-27

390

Determination of log P by dispersive liquid/liquid microextraction coupled with derivatized magnetic nanoparticles predispersed in 1-octanol phase.  

PubMed

A new direct method for log P determination by dispersive liquid/liquid microextraction (DLLME) coupled with derivatized magnetic nanoparticles (DMNPs) predispersed in 1-octanol phase is discussed. First, the aim of DMNPs predispersed into 1-octanol phase was to provide the magnetic force when an ultrastrong magnet was used to separate the two phases. Second, the interaction of 1-octanol with inner DMNPs nuclei prevented emulsion formation in the DLLME process. Moreover, interruption of absorption of DMNPs due to the partition equilibrium of the model compound was negligible. The equilibrium of model compound between the two phases was reached in less than 3 min. The two phases were separated quickly by a super magnet because model compounds in the two phases did not interfere with each other. Fourteen model compounds of varied log P values were measured using this method. The log P values fall in the range of 0.6 to 4.8, which are in agreement with the published results. This method is a rapid, efficient and facile method for direct measurement of log P values. PMID:22729045

Fu, Huafeng; Wang, Lina; Fan, Chunying; Li, Xiaomeng; Liang, Baoan

2012-01-01

391

Value Numbering  

Microsoft Academic Search

SUMMARY Value numbering is a compiler-based program analysis method that allows redundant computations to be removed. This paper compares hash-based approaches derived from the classic local algorithm1 with partitioning approaches based on the work of Alpern, Wegman, and Zadeck2. Historically, the hash-based algorithm has been applied to single basic blocks or extended basic blocks. We have improved the technique to

Preston Briggs; Keith D. Cooper; L. Taylor Simpson

1997-01-01

392

Expected Value  

NSDL National Science Digital Library

In this activity, students will use the random integer command on their graphing calculators to simulate rolling a die. They will then use operations on lists to analyze the probability of rolling the first 1 on the 1st roll, 2nd roll, and so on and finally find the expected value. Teacher notes explain in detail how to perform these actions on the graphing calculator.

2008-10-17

393

Fundamental Value and Market Value  

Microsoft Academic Search

Much of James Tobin's professional life has been devoted to studying the interrelationship between the goods and financial markets. His general equilibrium approaches stresses the interaction of the demand for financial assets with the decision to accumulate productive capital. His emphasis on q, the ratio of market value of assets to their replacement cost, has shaped how students of the

William C. Brainard; Matthew D. Shapiro; John B. Shoven

1990-01-01

394

Observed, unknown distributions of clinical chemical quantities should be considered to be log-normal: a proposal.  

PubMed

The distribution of many quantities in laboratory medicine are considered to be Gaussian if they are symmetric, although, theoretically, a Gaussian distribution is not plausible for quantities that can attain only non-negative values. If a distribution is skewed, further specification of the type is required, which may be difficult to provide. Skewed (non-Gaussian) distributions found in clinical chemistry usually show only moderately large positive skewness (e.g., log-normal- and ?(2) distribution). The degree of skewness depends on the magnitude of the empirical biological variation (CV(e)), as demonstrated using the log-normal distribution. A Gaussian distribution with a small CV(e) (e.g., for plasma sodium) is very similar to a log-normal distribution with the same CV(e). In contrast, a relatively large CV(e) (e.g., plasma aspartate aminotransferase) leads to distinct differences between a Gaussian and a log-normal distribution. If the type of an empirical distribution is unknown, it is proposed that a log-normal distribution be assumed in such cases. This avoids distributional assumptions that are not plausible and does not contradict the observation that distributions with small biological variation look very similar to a Gaussian distribution. PMID:20666698

Haeckel, Rainer; Wosniok, Werner

2010-07-29

395

Long-term responses of rainforest erosional systems at different spatial scales to selective logging and climatic change  

PubMed Central

Long-term (21–30 years) erosional responses of rainforest terrain in the Upper Segama catchment, Sabah, to selective logging are assessed at slope, small and large catchment scales. In the 0.44 km2 Baru catchment, slope erosion measurements over 1990–2010 and sediment fingerprinting indicate that sediment sources 21 years after logging in 1989 are mainly road-linked, including fresh landslips and gullying of scars and toe deposits of 1994–1996 landslides. Analysis and modelling of 5–15 min stream-suspended sediment and discharge data demonstrate a reduction in storm-sediment response between 1996 and 2009, but not yet to pre-logging levels. An unmixing model using bed-sediment geochemical data indicates that 49 per cent of the 216 t km?2 a?1 2009 sediment yield comes from 10 per cent of its area affected by road-linked landslides. Fallout 210Pb and 137Cs values from a lateral bench core indicate that sedimentation rates in the 721 km2 Upper Segama catchment less than doubled with initially highly selective, low-slope logging in the 1980s, but rose 7–13 times when steep terrain was logged in 1992–1993 and 1999–2000. The need to keep steeplands under forest is emphasized if landsliding associated with current and predicted rises in extreme rainstorm magnitude-frequency is to be reduced in scale.

Walsh, R. P. D.; Bidin, K.; Blake, W. H.; Chappell, N. A.; Clarke, M. A.; Douglas, I.; Ghazali, R.; Sayer, A. M.; Suhaimi, J.; Tych, W.; Annammala, K. V.

2011-01-01

396

Long-term responses of rainforest erosional systems at different spatial scales to selective logging and climatic change.  

PubMed

Long-term (21-30 years) erosional responses of rainforest terrain in the Upper Segama catchment, Sabah, to selective logging are assessed at slope, small and large catchment scales. In the 0.44 km(2) Baru catchment, slope erosion measurements over 1990-2010 and sediment fingerprinting indicate that sediment sources 21 years after logging in 1989 are mainly road-linked, including fresh landslips and gullying of scars and toe deposits of 1994-1996 landslides. Analysis and modelling of 5-15 min stream-suspended sediment and discharge data demonstrate a reduction in storm-sediment response between 1996 and 2009, but not yet to pre-logging levels. An unmixing model using bed-sediment geochemical data indicates that 49 per cent of the 216 t km(-2) a(-1) 2009 sediment yield comes from 10 per cent of its area affected by road-linked landslides. Fallout (210)Pb and (137)Cs values from a lateral bench core indicate that sedimentation rates in the 721 km(2) Upper Segama catchment less than doubled with initially highly selective, low-slope logging in the 1980s, but rose 7-13 times when steep terrain was logged in 1992-1993 and 1999-2000. The need to keep steeplands under forest is emphasized if landsliding associated with current and predicted rises in extreme rainstorm magnitude-frequency is to be reduced in scale. PMID:22006973

Walsh, R P D; Bidin, K; Blake, W H; Chappell, N A; Clarke, M A; Douglas, I; Ghazali, R; Sayer, A M; Suhaimi, J; Tych, W; Annammala, K V

2011-11-27

397

Logs of Paleoseismic Excavations Across the Central Range Fault, Trinidad  

USGS Publications Warehouse

This publication makes available maps and trench logs associated with studies of the Central Range Fault, part of the South American-Caribbean plate boundary in Trinidad. Our studies were conducted in 2001 and 2002. We mapped geomorphic features indicative of active faulting along the right-lateral, Central Range Fault, part of the South American-Caribbean plate boundary in Trinidad. We excavated trenches at two sites, the Samlalsingh and Tabaquite sites. At the Samlalsingh site, sediments deposited after the most recent fault movement bury the fault, and the exact location of the fault was unknown until we exposed it in our excavations. At this site, we excavated a total of eleven trenches, six of which exposed the fault. The trenches exposed fluvial sediments deposited over a strath terrace developed on Miocene bedrock units. We cleaned the walls of the excavations, gridded the walls with either 1 m X 1 m or 1 m X 0.5 m nail and string grid, and logged the walls in detail at a scale of 1:20. Additionally, we described the different sedimentary units in the field, incorporating these descriptions into our trench logs. We mapped the locations of the trenches using a tape and compass. Our field logs were scanned, and unit contacts were traced in Adobe Illustrator. The final drafted logs of all the trenches are presented here, along with photographs showing important relations among faults and Holocene sedimentary deposits. Logs of south walls were reversed in Illustrator, so that all logs are drafted with the view direction to the north. We collected samples of various materials exposed in the trench walls, including charcoal samples for radiocarbon dating from both faulted and unfaulted deposits. The locations of all samples collected are shown on the logs. The ages of seventeen of the charcoal samples submitted for radiocarbon analysis at the University of Arizona Accelerator Mass Spectrometry Laboratory in Tucson, Ariz., are given in Table 1. Samples found in Table 1 are shown in red on the trench logs. All radiocarbon ages are calibrated and given with 2 standard deviation age ranges. Our studies suggest that the Central Range Fault is a Holocene fault capable of producing damaging earthquakes in Trinidad

Crosby, Christopher J.; Prentice, Carol S.; Weber, John; Ragona, Daniel

2009-01-01

398

ANDRILL Borehole AND-1B: Well Log Analysis of Lithofacies and Glacimarine Cycles.  

NASA Astrophysics Data System (ADS)

During the 2006-2007 austral summer, the Antarctic geological drilling program ANDRILL recovered cores of sedimentary rock from a 1285-m-deep borehole below the McMurdo Ice Shelf. Well logging instruments were deployed to a depth of 1017 mbsf after core recovery. This study focuses on two intervals of the AND-1B borehole: upper HQ (238-343 mbsf; Pliocene) and NQ (698-1017 mbsf; upper Miocene), which were logged with natural gamma ray, induction resistivity and magnetic susceptibility tools. To understand how the well logs fit into a more complete physical properties data set, we performed factor and cluster analyses on a suite of well logs and core logs in the upper HQ and NQ intervals. In both intervals, factor analysis groups resistivity and core P-velocity into a factor that we interpret as being inversely proportional to porosity. It also groups natural gamma and potassium (from the XRF core scanner) into a factor that we interpret as a particle-size or lithology index. An additional factor in the NQ interval, influenced by clast number and magnetic susceptibility, distinguishes subglacial diamictites from other lithofacies. The factors in each interval (2 in HQ, 3 in NQ) are used as input to cluster analysis. The results are log data objectively organized into clusters, or electrofacies. We compare these electrofacies to the lithofacies, well logs and unconformity-bounded glacimarine cycles of AND-1B. Patterns in the glacimarine cycles are observed in the well logs and electrofacies. In the NQ glacimarine sediments, an electrofacies pattern is produced between subglacial diamictites at the bottom of each sequence and the glacial retreat facies above. Subglacial diamictites have higher values for the additional NQ factor, corresponding to clast number and magnetic susceptibility, than the muds and sands that form the retreat facies. Differences in the porosity factor are not observed in any electrofacies pattern in the NQ interval, but subtle patterns in the resistivity well log are observed. Subglacial diamictites have greater resistivities than most retreat facies. In the HQ interval, there is only one glacimarine cycle that resembles those in the NQ interval, and most of the interval is subglacial or ice-proximal diamictite. There are only two and a half cycles in the HQ interval, but they contain an incipient electrofacies pattern. In the lower two cycles, the potassium/gamma factor is low at the bottom and high toward the top, and porosity, as indicated by the porosity factor, is low at the bottom and high toward the top. Throughout most of the HQ interval, potassium and natural gamma correlate with porosity. Two exceptions are the lower half of the top cycle, in which resistivity increases toward the top, and the two diatomite beds at the top of the two lower cycles, in which potassium/gamma is low and porosity is very high.

Jackolski, C. L.; Williams, T.; Powell, R. D.; Jarrard, R.; Morin, R. H.; Talarico, F. M.; Niessen, F.; Kuhn, G.

2008-12-01

399

A large sample of calibration stars for Gaia: log g from Kepler and CoRoT fields  

NASA Astrophysics Data System (ADS)

Asteroseismic data can be used to determine stellar surface gravities with precisions of <0.05 dex by using the global seismic quantities and ?max along with standard atmospheric data such as Teff and metallicity. Surface gravity is also one of the four stellar properties to be derived by automatic analyses for one billion stars from Gaia data (workpackage GSP_PHOT). In this paper, we explore seismic data from main-sequence F, G, K stars (solar-like stars) observed by the Kepler spacecraft as a potential calibration source for the methods that Gaia will use for object characterization (log g). We calculate log g for some bright nearby stars for which radii and masses are known (e.g. from interferometry or binaries), and using their global seismic quantities in a grid-based method, we determine an asteroseismic log g to within 0.01 dex of the direct calculation, thus validating the accuracy of our method. We also find that errors in adopted atmospheric parameters (mainly [Fe/H]) can, however, cause systematic errors of the order of 0.02 dex. We then apply our method to a list of 40 stars to deliver precise values of surface gravity, i.e. uncertainties of the order of 0.02 dex, and we find agreement with recent literature values. Finally, we explore the typical precision that we expect in a sample of more than 400 Kepler stars which have their global seismic quantities measured. We find a mean uncertainty (precision) of the order of better than 0.02 dex in log g over the full explored range 3.8 < log g < 4.6, with the mean value varying only with stellar magnitude (0.01-0.02 dex). We study sources of systematic errors in log g and find possible biases of the order of 0.04 dex, independent of log g and magnitude, which accounts for errors in the Teff and [Fe/H] measurements, as well as from using a different grid-based method. We conclude that Kepler stars provide a wealth of reliable information that can help to calibrate methods that Gaia will use, in particular, for source characterization with GSP_PHOT, where excellent precision (small uncertainties) and accuracy in log g is obtained from seismic data.

Creevey, O. L.; Thévenin, F.; Basu, S.; Chaplin, W. J.; Bigot, L.; Elsworth, Y.; Huber, D.; Monteiro, M. J. P. F. G.; Serenelli, A.

2013-05-01

400

User's manual for geophysical well-logging software programs  

SciTech Connect

Since 1958 the Ground-Water Surveillance Program for the Hanford Site has made geophysical logging measurements in most of the 800 wells and deep boreholes that have been drilled on the Hanford Site. In 1980 the Pacific Northwest Laboratory (PNL), which conducts the Ground-Water Surveillance Program, began forming a computerized data base for storing and retrieving geophysical well log data and developing software for quantitative analysis of the well log data. This report, designed to serve as a user's guide, documents the data base system that handles the well log data. Two programs, DIGLOG1 and LOGIT, are used to manipulate the data. The program DIGLOG1 translates analog paper strip charts into digital format; the program LOGIT is a general utility program that edits, displays, checks, stores, writes, and deletes sets of well log data. These two programs do not provide sophisticated display and analytical capabilities; rather, they provide programs that give the user easy access to powerful standard analytical software.

Petrie, G.M.; Gibson, D.; Blair, S.C.

1983-02-01

401

Technical evaluation of software for gamma-ray logging system  

SciTech Connect

This report contains results of a technical review of software, identified as LGCALC, that processes data collected by a high-resolution gamma-ray borehole logging system. The software presently operates within Westinghouse Hanford Company, Department of Geosciences, to process data collected by the Radionuclide Logging System. The software has been reviewed for its suitability for processing data to be collected by new high-resolution gamma-ray logging trucks scheduled to begin operational tests within Westinghouse Tank Waste Remediation Systems during 1994. Examination of the program code and hands-on operational tests have shown that this software is suitable for its intended use of processing high-resolution gamma-ray data obtained from borehole logging. Most of the code requires no changes, but in a few limited cases, suggestions have been made to correct errors or improve operation. Section 4 describes these changes. The technical review has confirmed the appropriateness, correctness, completeness, and coding accuracy of algorithms used to process spectral gamma-ray data, leading to a calculation of subsurface radionuclide contaminants. Running the program with test data from calibration models has confirmed that the program operates correctly. Comparisons with hand calculations have shown the correctness of the output from the program, based on known input data. Section 3 describes these tests. The recommended action is to make the near term programming changes suggested in Section 4.1 and then use the LGCALC analysis program with the new high-resolution logging systems once they have been properly calibrated.

Stromswold, D.C.

1994-05-01

402

Model for water factor measurements with fission-neutron logging tools. National Uranium Resource Evaluation  

SciTech Connect

During 1977 and 1978, a Fission Neutron Water Factor Model was designed and constructed by Bendix Field Engineering Corporation (BFEC) for the United States Department of Energy (DOE) at the Grand Junction facility. This model features seven water-filled boreholes with different diameters. All of these boreholes penetrate, in order from the top of the model, a 5-foot-thick (1.52 m), uniform, concrete upper ''barren zone''; a 6-foot-thick (1.83 m), uniform, uranium-enriched, concrete ''ore zone''; and a 4-foot-thick (1.22 m), uniform, concrete lower ''barren zone''. The response of a fission neutron logging tool in a water-filled borehole is affected by variations in the borehole diameter. This diameter-dependent effect can be deduced from logs run in several different boreholes of the Fission Neutron Water Factor Model. This report describes the construction of the Fission Neutron Water Factor Model and also presents values for model parameters which are of interest in fission-neutron logging.

Koizumi, C. J.

1983-05-01

403

A smooth ROC curve estimator based on log-concave density estimates.  

PubMed

We introduce a new smooth estimator of the ROC curve based on log-concave density estimates of the constituent distributions. We show that our estimate is asymptotically equivalent to the empirical ROC curve if the underlying densities are in fact log-concave. In addition, we empirically show that our proposed estimator exhibits an efficiency gain for finite sample sizes with respect to the standard empirical estimate in various scenarios and that it is only slightly less efficient, if at all, compared to the fully parametric binormal estimate in case the underlying distributions are normal. The estimator is also quite robust against modest deviations from the logconcavity assumption. We show that bootstrap confidence intervals for the value of the ROC curve at a fixed false positive fraction based on the new estimate are on average shorter compared to the approach by Zhou and Qin (2005), while maintaining coverage probability. Computation of our proposed estimate uses the R package logcondens that implements univariate log-concave density estimation and can be done very efficiently using only one line of code. These obtained results lead us to advocate our estimate for a wide range of scenarios. PMID:22611590

Rufibach, Kaspar

2012-01-01

404

Assessing the use of butterflies as indicators of logging in Borneo at three taxonomic levels.  

PubMed

Logging is an issue of major conservation concern. Less than 5% of tropical forests are currently protected, and many of these are in so-called "paper parks." Many species may therefore depend on exploited forests, and management decisions concerning these forests will be a major determinant of their survival. An important aspect of forest management will entail the use of reliable, practical, and inexpensive indicator taxa to monitor exploitation. Here, butterflies are proposed as such indicators. Species, generic, and subfamily richness was significantly higher in logged than unlogged forest and community composition differed significantly at all three taxonomic levels (species, genus, and subfamily). Richness estimators were, furthermore, highly correlated among all three taxonomic levels. Significant individual indicator taxa were found at all three taxonomic levels, but the best overall taxa (highest indicator values) were found at the generic level and included the butterfly genera Ragadia and Paralaxita as indicators of unlogged forest and the genera Ypthima, Allotinus, and Athyma as indicators of logged forest. The use of genera instead of species presents a number of practical advantages. Identification is faster, easier, and more reliable. Genera can, furthermore, usually be identified "on the wing," thereby preventing accidental mortality due to capture. PMID:15154465

Cleary, Daniel F R

2004-04-01

405

Limit Distribution Theory for Maximum Likelihood Estimation of a Log-Concave Density  

PubMed Central

We find limiting distributions of the nonparametric maximum likelihood estimator (MLE) of a log-concave density, i.e. a density of the form f0 = exp ?0 where ?0 is a concave function on ?. Existence, form, characterizations and uniform rates of convergence of the MLE are given by Rufibach (2006) and Dümbgen and Rufibach (2007). The characterization of the log–concave MLE in terms of distribution functions is the same (up to sign) as the characterization of the least squares estimator of a convex density on [0, ?) as studied by Groeneboom, Jongbloed and Wellner (2001b). We use this connection to show that the limiting distributions of the MLE and its derivative are, under comparable smoothness assumptions, the same (up to sign) as in the convex density estimation problem. In particular, changing the smoothness assumptions of Groeneboom, Jongbloed and Wellner (2001b) slightly by allowing some higher derivatives to vanish at the point of interest, we find that the pointwise limiting distributions depend on the second and third derivatives at 0 of Hk, the “lower invelope” of an integrated Brownian motion process minus a drift term depending on the number of vanishing derivatives of ?0 = log f0 at the point of interest. We also establish the limiting distribution of the resulting estimator of the mode M(f0) and establish a new local asymptotic minimax lower bound which shows the optimality of our mode estimator in terms of both rate of convergence and dependence of constants on population values.

Balabdaoui, Fadoua; Rufibach, Kaspar; Wellner, Jon A.

2009-01-01

406

Is there a universal log law for turbulent wall-bounded flows?  

PubMed

The history and theory supporting the idea of a universal log law for turbulent wall-bounded flows are briefly reviewed. The original idea of justifying a log law from a constant Reynolds stress layer argument is found to be deficient. By contrast, it is argued that the logarithmic friction law and velocity profiles derived from matching inner and outer profiles for a pipe or channel flow are well-founded and consistent with the data. But for a boundary layer developing along a flat plate it is not, and in fact it is a power law theory that seems logically consistent. Even so, there is evidence for at least an empirical logarithmic fit to the boundary-friction data, which is indistinguishable from the power law solution. The value of kappa approximately 0.38 obtained from a logarithmic curve fit to the boundary-layer velocity data, however, does not appear to be the same as for pipe flow for which 0.43 appears to be the best estimate. Thus, the idea of a universal log law for wall-bounded flows is not supported by either the theory or the data. PMID:17244592

George, William K

2007-03-15

407

Experimental correlation between the pKa value of sulfonphthaleins with the nature of the substituents groups.  

PubMed

This work presents the results obtained from a spectrophotometry study performed on some indicators of the sulfonphtaleins like phenol red (PR), thymol blue (TB), bromothymol blue (BTB), xylenol orange (XO) and methylthymol blue (MTB). During the first stage the acidity constants of some of the indicators were determined using the data from spectrophotometry, potentiometry and with the use of the software SQUAD. These were as follows: for the equilibrium 2H+BTB<-->H(2)BTB, log beta(2)=15.069+/-0.046 and for H+BTB<-->HBTB, log beta(1)=8.311+/-0.044. For the XO and the MTB five values were calculated for each, namely, for MTB: log beta(5)=42.035, log beta(4)=38.567+/-0.058, log beta(3)=32.257+/-0.057, log beta(2)=23.785+/-0.057, and log beta(1)=12.974+/-0.045 while for XO: log beta(5)=40.120+/-0.102, log beta(4)=35.158+/-0.062, log beta(3)=29.102+/-0.053, log beta(2)=21.237+/-0.044, and log beta(1)=11.682+/-0.044. During the second stage, a study was conducted on the effect of the substituents present in the indicators to determine the effect of different functional groups on the pK(a) value corresponding to the last indicator's dissociation. PMID:17716940

Balderas-Hernández, Patricia; Ramírez-Silva, María Teresa; Romero-Romo, Mario; Palomar-Pardavé, Manuel; Roa-Morales, Gabriela; Barrera-Diaz, Carlos; Rojas-Hernández, Alberto

2007-07-17

408

A novel quantum representation for log-polar images  

NASA Astrophysics Data System (ADS)

The power of quantum mechanics has been extensively exploited to meet the high computational requirement of classical image processing. However, existing quantum image models can only represent the images sampled in Cartesian coordinates. In this paper, quantum log-polar image (QUALPI), a novel quantum image representation is proposed for the storage and processing of images sampled in log-polar coordinates. In QUALPI, all the pixels of a QUALPI are stored in a normalized superposition and can be operated on simultaneously. A QUALPI can be constructed from a classical image via a preparation whose complexity is approximately linear in the image size. Some common geometric transformations, such as symmetry transformation, rotation, etc., can be performed conveniently with QUALPI. Based on these geometric transformations, a fast rotation-invariant quantum image registration algorithm is designed for log-polar images. Performance comparison with classical brute-force image registration method reveals that our quantum algorithm can achieve a quartic speedup.

Zhang, Yi; Lu, Kai; Gao, Yinghui; Xu, Kai

2013-09-01

409

The Message Logging System for NO?A Experiment  

NASA Astrophysics Data System (ADS)

The message logging system provides the infrastructure for all of the distributed processes in the data acquisition (DAQ) to report status messages of various severities in a consistent manner to a central location, as well as providing the tools for displaying and archiving the messages. The message logging system has been developed over a decade, and has been run successfully on CDF and CMS experiments. The most recent work to the message logging system is to build it as a stand-alone package with the name MessageFacility which works for any generic framework or applications, with NO?A as the first driving user. System designs and architectures, as well as the efforts of making it a generic library will be discussed. We also present new features that have been added.

Lu, Qiming; Kowalkowski, J. B.; Biery, K. A.

2011-12-01

410

CosmicEmuLog: Cosmological Power Spectra Emulator  

NASA Astrophysics Data System (ADS)

CosmicEmuLog is a simple Python emulator for cosmological power spectra. In addition to the power spectrum of the conventional overdensity field, it emulates the power spectra of the log-density as well as the Gaussianized density. It models fluctuations in the power spectrum at each k as a linear combination of contributions from fluctuations in each cosmological parameter. The data it uses for emulation consist of ASCII files of the mean power spectrum, together with derivatives of the power spectrum with respect to the five cosmological parameters in the space spanned by the Coyote Universe suite. This data can also be used for Fisher matrix analysis. At present, CosmicEmuLog is restricted to redshift 0.

Neyrinck, Mark

2013-04-01

411

Detection of landsides in shield volcanoes from magnetic logging - an example from Mauna Kea/Hawaii  

NASA Astrophysics Data System (ADS)

A quasi-continuous magnetic log has been obtained in the Hawaii Scientific Drilling Project 2 (HSDP-2), providing information down to 1800 mbsl of Mauna Kea volcano flank deposits. The HSDP borehole penetrates series of Aa- and Pahoehoe subaerial lava flows down to 1100 mbsl followed by submarine series of volcniclastics with intercalated massive flows. The borehole magnetometer was employed to measure the horizontal and vertical magnetic fields. Measurements were taken in downhole and uphole runs, with a good correlation between both runs.. Magnetic borehole logging in the HSDP-2 hole reveals strong magnetic anomalies in the subaerial as well in the submarine part with deviations from the normal field of up to 15000 nT. Mean inclination calculated from logging data is 22.7 °, which differs significantly from the present day inclination of 36.7° (IGRF95 reference field). The frequency distribution of inclination estimated for different rock types is clearly shifted towards lower values for rocks of the submarine part of the hole. In this lower part a decrease of magnetic inclination is observed which changes abruptly. These deviations of up to 20° are hardly explained by secular variation of the magnetic main field. Also flexural deformation of the oceanic crust by the load of the Hawaiian Island yields tilt angles, which are too small to explain the observed deviations. On the other hand mass movements, e.g. landslides and debris avalanches are well known processes, which modify the morphology of shield volcanoes during their lifetime. The interpretation of petrophysical logging data from the submarine part of HSDP-II provides strong indications for landslides during the stage of seacliff formation. Core and petrophysical logging data indicate larger mass movements between 1570 and 1670 mbsl. Here, a prominent boundary is located where petrophysical characteristics abruptly change. The boundary marks a significant decrease in rock porosity within the hyaloclastites accompanied by a strong temperature increase below this boundary. This boundary correlates well with an abrupt change in magnetic inclination to lower values.

Pechnig, R.; Stoll, J.; Steveling, E.; Buysch, A.

2003-04-01

412

Electromagnetic-induction logging to monitor changing chloride concentrations.  

PubMed

Water from the San Joaquin Delta, having chloride concentrations up to 3590 mg/L, has intruded fresh water aquifers underlying Stockton, California. Changes in chloride concentrations at depth within these aquifers were evaluated using sequential electromagnetic (EM) induction logs collected during 2004 through 2007 at seven multiple-well sites as deep as 268 m. Sequential EM logging is useful for identifying changes in groundwater quality through polyvinyl chloride-cased wells in intervals not screened by wells. These unscreened intervals represent more than 90% of the aquifer at the sites studied. Sequential EM logging suggested degrading groundwater quality in numerous thin intervals, typically between 1 and 7 m in thickness, especially in the northern part of the study area. Some of these intervals were unscreened by wells, and would not have been identified by traditional groundwater sample collection. Sequential logging also identified intervals with improving water quality-possibly due to groundwater management practices that have limited pumping and promoted artificial recharge. EM resistivity was correlated with chloride concentrations in sampled wells and in water from core material. Natural gamma log data were used to account for the effect of aquifer lithology on EM resistivity. Results of this study show that a sequential EM logging is useful for identifying and monitoring the movement of high-chloride water, having lower salinities and chloride concentrations than sea water, in aquifer intervals not screened by wells, and that increases in chloride in water from wells in the area are consistent with high-chloride water originating from the San Joaquin Delta rather than from the underlying saline aquifer. PMID:22607466

Metzger, Loren F; Izbicki, John A

2012-05-18

413

Vacuum-soaking of wood chip shiitake (Lentinula edodes) logs to reduce soak time and log weight variability and to stimulate mushroom yield.  

PubMed

Synthetic logs were vacuum-soaked or regular-soaked to determine the effects of soaking on yield and mushroom size, log weight variability and water distribution within the log. Yields (g/log) from substrates vacuum-soaked were higher by 26.7%, 18.6% and 35.8% (mean = 27.2%) for crops I, II and III, respectively, when compared with regular-soaked. However, mushroom size averaged only 11.2 g for vacuum-soaked logs vs 17 g for regular-soaked logs (51.8% larger for regular-soaked). The time required for vacuum-soaking logs was generally less than 3 min, compared with regular-soaking times ranging over 3-15 h. Water tended to accumulate more in the outside zone in the vacuum-soaked logs, compared with regular-soaked logs. Mean moisture contents for crops I and II for outside, middle and interior zones of vacuum-soaked logs were 66%, 47.5% and 42.2%, respectively, while regular-soaked logs for the same zones were 62.4%, 52.1% and 50.9%, respectively. Vacuum-soaked log weights had lower standard deviations than weights for regular-soaked logs in four out of six soaks, indicating a more uniform soaking process. PMID:11833530

Royse, D J; Rhodes, T W; Sanchez, J E

2002-01-01

414

Log-ratio technique for beam position monitor systems  

SciTech Connect

Recent progress in the development of a beam position monitor system (BPM), based on the log-ratio technique, is described in this paper. A complete electronic analysis is presented, showing linearity, dynamic range, noise, RF burst response, and temperature dependence. A calibration technique has been developed, which corrects the errors due to mismatched channels and electronics drift. This technique is particularly effective because of the log-ratio property for beam position monitoring. This circuit is the most likely candidate for beam position monitor electronics at the SSC.

Roberto Aiello, G.; Mills, M.R. (Superconducting Super Collider Laboratory, 2550 Beckleymeade Ave., Dallas, TX 75237 (United States))

1992-07-10

415

Comprehensive analysis of the carbon/oxygen log  

SciTech Connect

A study is presented on the analysis of induced gamma ray spectroscopy logs. This report reviews the current interpretation methods and presents a cross-plotting technique to compute hydrocarbon saturation. The cross-plotting technique has three unknowns: porosity, volumetric fraction of shale and oil saturation. The only constraint upon this technique is that porosity must be fairly constant in the reservoir. The Dresser Atlas Continuous Carbon/Oxygen Log is being run periodically in the observation wells of a steam-foam pilot in Kern County, California to monitor the recovery process. A comparison is made between the cross-plot method and other methods. 60 figures, 7 tables. (DLC)

O'Brien, W.J.; Sanyal, S.K.; Brown, S.L.

1983-01-01

416

Quality control log with CUSUM and clinically useful limits criteria.  

PubMed

We describe a quality control (QC) log including its advantages over the more commonly used Levey-Jennings and Shewart graphic charts. It represents a practical system of analytic quality control for quantitative assays in clinical chemistry. It utilizes cumulative sum (CUSUM) techniques and comparison of means to monitor acute and chronic analytic drift, respectively. Clinically useful limits (CUL) criteria for QC decisions are used. An algorithm to facilitate the description of, training for, and use of, the QC log system is provided. PMID:3838642

Schoen, I; Custer, E; Graham, G; Bandi, Z; Surovik, M H

1985-04-01

417

P-Value Precision and Reproducibility  

PubMed Central

Summary P-values are useful statistical measures of evidence against a null hypothesis. In contrast to other statistical estimates, however, their sample-to-sample variability is usually not considered or estimated, and therefore not fully appreciated. Via a systematic study of log-scale p-value standard errors, bootstrap prediction bounds, and reproducibility probabilities for future replicate p-values, we show that p-values exhibit surprisingly large variability in typical data situations. In addition to providing context to discussions about the failure of statistical results to replicate, our findings shed light on the relative value of exact p-values vis-a-vis approximate p-values, and indicate that the use of *, **, and *** to denote levels .05, .01, and .001 of statistical significance in subject-matter journals is about the right level of precision for reporting p-values when judged by widely accepted rules for rounding statistical estimates.

Boos, Dennis D.; Stefanski, Leonard A.

2011-01-01

418

Suppression of Log-Weibull Distributed Sea-Ice Clutter Using a Modified LOG/CFAR System  

NASA Astrophysics Data System (ADS)

We observed sea-ice clutter using a millimeter wave radar with a frequency 34.860 GHz, a beamwidth 0.25°, and a plusewidth 30 ns which is located at the city of Mombetsu in Hokkaido. To determine the sea-ice clutter amplitude, we introduce the Akaike Information Criterion (AIC). It is discovered that the sea-ice clutter amplitudes obey the log-Weibull distribution with the shape parameters of 2.36 to 2.93 in terms of the temporal and small scale range fluctuations with which a constant false alarm rate (CFAR) is concerned. We propose a new log-Weibull/CFAR system uses a modified cell-averaging LOG/CFAR system. It is found that sea-ice clutter is suppressed with the improvement of more than 40 dB.

Sayama, Shuji; Ishii, Seishiro; Sekine, Matsuo

419

Interpretation of ES-Logs. Final Report, October 1991-April 1995.  

National Technical Information Service (NTIS)

There are roughly 500,000 electric logs (ES-logs) for wells in the U.S. Many of these are in cased wells, precluding the possibility of further resistivity logging. Thus, these old ES-logs are an invaluable resource for the possible reentry of older field...

W. W. Whitman

1995-01-01

420

Interpretation of ES-Logs. Annual Report, October 1992-September 1993.  

National Technical Information Service (NTIS)

There are roughly 500,000 electric logs (ES-logs) for wells in the U.S. Many of these are in cased wells, precluding the possibility of further resistivity logging. Thus, these old ES-logs are an invaluable resoure for the possible reentry of older fields...

W. W. Whitman

1993-01-01

421

Interpretation of ES-Logs. Annual Report, October 1991-September 1992.  

National Technical Information Service (NTIS)

There are roughly 500,000 electric logs (ES-logs) for wells in the U.S. Many of these are in cased wells, precluding the possibility of further resistivity logging. Thus, these old ES-logs are an invaluable resource for the possible reentry of older field...

W. W. Whitman

1992-01-01

422

User k-anonymity for privacy preserving data mining of query logs  

Microsoft Academic Search

The anonymization of query logs is an important process that needs to be performed prior to the publication of such sensitive data. This ensures the anonymity of the users in the logs, a problem that has been already found in released logs from well known companies. This paper presents the anonymization of query logs using microaggregation. Our proposal ensures the

Guillermo Navarro-Arribas; Vicenç Torra; Arnau Erola; Jordi Castellà-Roca

423

Experimental setup affects the particle formation rate and its slope d(log J)/d(log C)  

NASA Astrophysics Data System (ADS)

We have simulated the formation of sulfuric acid-dimethylamine clusters in different experimental setups and in the atmosphere. We demonstrate that the cluster formation rate may be different in flow tube experiments than in chamber experiments due to the depletion of some trace compound. We also show that applying the nucleation theorem in a situation where all its assumptions do not hold may lead to erroneous results: the slope d(log J)/d(log C) of the formation rate versus the sulfuric acid concentration is in many conditions 4, although each step of the formation process decreases the Gibbs energy of the system and there is no critical cluster.

Kupiainen, Oona; Olenius, Tinja; Vehkamäki, Hanna

2013-05-01

424

Effects of variable retention logging in the boreal forest on the bumble bee-influenced pollination community, evaluated 8–9 years post-logging  

Microsoft Academic Search

Boreal forests are currently facing intensified logging pressures, yet we know little about impacts of logging on the pollination community. This study extends research done immediately before and after logging, to consider its longer term effects. We censused bumble bee and flower communities 8–9 years after experimental variable retention logging. Harvest treatments left 0%, 10–20%, 50–75%, or 100% of the

Chris J. Pengelly; Ralph V. Cartar

2010-01-01

425

Modified log-wake law for turbulent flow in smooth pipes Loi log-trainée modifiée pour écoulement turbulent en conduite à paroi lisse  

Microsoft Academic Search

A modified log-wake law for turbulent flow in smooth pipes is developed and tested with laboratory data. The law consists of three terms: a log term, a sine-square term and a cubic term. The log term reflects the restriction of the wall, the sine-square term expresses the contribution of the pressure gradient, and the cubic term makes the standard log-wake

JUNKE GUO; PIERRE Y. JULIEN

2003-01-01

426

Promoting Reduced-Impact Logging in Tropical Developing Countries  

Treesearch

All Treesearch publications were written or produced by Forest Service ... Reduced-Impact Logging in Tropical Developing Countries: A Success Story of ... to significant compaction and erosion; loggers typically have little education, are ... government technical-assistance programs; and international agencies such as the ...

427

Estimation of mineralogy and lithology from geochemical log measurements  

Microsoft Academic Search

Mineralogy, chemistry, and physical properties of core samples from a research well in Grand County, Utah, have been determined to assess the applications of geochemical logging tool measurements to reservoir characterization. The cored interval (over 827 ft or 252 m of continuous core) samples a wide range of lithologies, including subarkose, sublitharenite, litharenite, feldspathic litharenite, quartz wacke, lithic wacke, siltstone,

R. F. Wndlandt; K. Bhuyan

1990-01-01

428

Core - log integration of petrophysical lithofacies at the Nankai Trough  

Microsoft Academic Search

Characterising the physical properties and identifying boundaries within active accretionary prisms is necessary to understand their behaviour and recent movement. In such unstable conditions core recovery is not always reliable, especially close to fault zones. Multiple sites drilled during IODP Expeditions 314 - 316 for the first stage of the Nankai Trough Seismogenic Zone Experiment (NanTroSEIZE) used logging while drilling

J. Tudge; S. Saito; S. J. Davies; M. Lovell; P. K. Harvey

2009-01-01

429

Mining search engine query logs via suggestion sampling  

Microsoft Academic Search

Many search engines and other web applications suggest auto-completions as the user types in a query. The sugges- tions are generated from hidden underlying databases, such as query logs, directories, and lexicons. These databases consist of interesting and useful information, but they are typically not directly accessible. In this paper we describe two algorithms for sampling sug- gestions using only

Ziv Bar-yossef; Maxim Gurevich

2008-01-01

430

Mining search engine query logs for query recommendation  

Microsoft Academic Search

This paper presents a simple and intuitive method for min- ing search engine query logs to get fast query recommenda- tions on a large scale industrial-strength search engine. In order to get a more comprehensive solution, we combine two methods together. On the one hand, we study and model search engine users' sequential search behavior, and inter- pret this consecutive

Zhiyong Zhang; Olfa Nasraoui

2006-01-01

431

Store well-logging data with ObjectStore ODBMS  

NASA Astrophysics Data System (ADS)

How to store well-logging data in a database is a problem encountered by developers of exploration software. A method to store these data with an ODBMS is presented; C+ + is the programming language and ObjectStore the database system. This method is applied to the development of GRIstation—a joint project between GRI China and STS USA.

Li, Haifei

1995-12-01

432

Prediction of fracture gradients from log derived elastic moduli  

Microsoft Academic Search

Thirty-five measured fracture gradients in 10 fields are included in this study. The procedure utilizes all plugback operations from open hole, both into surface pipe and production strings or liners. Sonic and density logs have been obtained where possible from wells in the fields with measured breakdown gradients. Unfortunately, offshore logistics, risks, costs, and particularly hole conditions in highly deviated,

L. A. MacPherson; L. N. Berry

1972-01-01

433

Using the Web Server Logs to Study Public Opinion  

Microsoft Academic Search

With the help of Webometrics techniques, we could explore whether or not the Web surfer's online interest reflects the public opinion off-line. This paper investigates the Chinese Web user's interest regarding the United States and Japan, and demonstrates that Web server log data could be a good source for us to gauge the public opinion on specific domestic and international

Yijun Gao

434

Logging, a bigger threat to the rainforest than we knew  

NSDL National Science Digital Library

The amount of land in the Amazon rainforest that's being damaged by human activities is twice as large as we had previously thought, suggests a new study. That's because researchers didn't have a good idea of how much logging was occurring there, until now.

American Association for the Advancement of Science (AAAS;)

2005-10-20

435

Fluid-Rock Characterization and Interactions in NMR Well Logging  

SciTech Connect

The objective of this report is to characterize the fluid properties and fluid-rock interactions that are needed for formation evaluation by NMR well logging. The advances made in the understanding of NMR fluid properties are summarized in a chapter written for an AAPG book on NMR well logging. This includes live oils, viscous oils, natural gas mixtures, and the relation between relaxation time and diffusivity. Oil based drilling fluids can have an adverse effect on NMR well logging if it alters the wettability of the formation. The effect of various surfactants on wettability and surface relaxivity are evaluated for silica sand. The relation between the relaxation time and diffusivity distinguishes the response of brine, oil, and gas in a NMR well log. A new NMR pulse sequence in the presence of a field gradient and a new inversion technique enables the T{sub 2} and diffusivity distributions to be displayed as a two-dimensional map. The objectives of pore morphology and rock characterization are to identify vug connectivity by using X-ray CT scan, and to improve NMR permeability correlation. Improved estimation of permeability from NMR response is possible by using estimated tortuosity as a parameter to interpolate between two existing permeability models.

George J. Hirasaki; Kishore K. Mohanty

2005-09-05

436

Application of Nuclear Well Logging Techniques to Lunar Resource Assessment.  

National Technical Information Service (NTIS)

The use of neutron and gamma ray measurements for the analysis of material composition has become well established in the last 40 years. Schlumberger has pioneered the use of this technology for logging wells drilled to produce oil and gas, and for this p...

P. Albats J. Groves J. Schweitzer T. Tombrello

1992-01-01

437

Investigative Profiling with Computer Forensic Log Data and Association Rules  

Microsoft Academic Search

Investigative profiling is an important activity in computer forensics that can narrow the search for one or more computer perpetrators. Data mining is a technique that has produced good results in providing insight into large volumes of data. This paper describes how the association rule data mining technique may be employed to generate profiles from log data and the methodology

Tamas Abraham; Olivier Y. De Vel

2002-01-01

438

Mining Web Access Logs Using Relational Competitive Fuzzy Clustering  

Microsoft Academic Search

The proliferation of information on the world wide web has made the personalization of this information space a necessity. An important component of web personaliza- tion is to mine typical user profiles from the vast amount of historical data stored in access logs. In this paper, we define the notion of a \\

Olfa Nasraoui; Anupam Joshi; Raghu Krishnapuram

1999-01-01

439

12. LOG FOUNDATION ELEMENTS OF THE SAWMILL ADJACENT TO THE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. LOG FOUNDATION ELEMENTS OF THE SAWMILL ADJACENT TO THE CANAL, LOOKING EAST. BARREN AREA IN FOREGROUND IS DECOMPOSING SAWDUST. DIRT PILE IN BACKGROUND IS THE EDGE OF THE SUMMIT COUNTY LANDFILL. - Snake River Ditch, Headgate on north bank of Snake River, Dillon, Summit County, CO

440

DARK ENERGY FROM THE LOG-TRANSFORMED CONVERGENCE FIELD  

SciTech Connect

A logarithmic transform of the convergence field improves 'the information content', i.e., the overall precision associated with the measurement of the amplitude of the convergence power spectrum, by improving the covariance matrix properties. The translation of this improvement in the information content to that in cosmological parameters, such as those associated with dark energy, requires knowing the sensitivity of the log-transformed field to those cosmological parameters. In this paper, we use N-body simulations with ray tracing to generate convergence fields at multiple source redshifts as a function of cosmology. The gain in information associated with the log-transformed field does lead to tighter constraints on dark energy parameters, but only if shape noise is neglected. The presence of shape noise quickly diminishes the advantage of the log-mapping, more quickly than we would expect based on the information content. With or without shape noise, using a larger pixel size allows for a more efficient log-transformation.

Seo, Hee-Jong [Berkeley Center for Cosmological Physics, LBL and Department of Physics, University of California, Berkeley, CA 94720 (United States); Sato, Masanori [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan); Takada, Masahiro [Institute for the Physics and Mathematics of the Universe (IPMU), University of Tokyo, Chiba 277-8582 (Japan); Dodelson, Scott, E-mail: hee-jongseo@lbl.gov [Center for Particle Astrophysics, Fermi National Accelerator Laboratory, Batavia, IL 60510 (United States)

2012-03-20

441

CT IMAGING, DATA REDUCTION, AND VISUALIZATION OF HARDWOOD LOGS  

Microsoft Academic Search

Computer tomography (CT) is a mathematical technique that, combined with noninvasive scanning such as x-ray imaging, has become a powerful tool to nondestructively test materials prior to use or to evaluate materials prior to processing. In the current context, hardwood lumber processing can benefit greatly by knowing what a log looks like prior to initial breakdown, Previous research has indicated

Daniel L. Schmoldt

442

Trends in acoustic velocity log technology at RD Instruments  

Microsoft Academic Search

RD Instruments (RDI) has been the leading manufacturer of acoustic Doppler current profilers (ADCP) for many years. Sales of our products for use primarily as navigation sonars or Doppler velocity logs (DVL) have been limited until recently by issues of size, weight, and cost. In 1995, RDI introduced the Workhorse product line which dramatically reduced the size, weight, and cost

Joel Young; Fran Rowe; B. Brumley; Steve Bradley

1998-01-01

443

A 1-V CMOS log-domain integrator  

Microsoft Academic Search

A novel circuit implementation of a CMOS log-domain integrator is presented. Unlike most other implementations, it does not require placing of MOSFETs in separated wells, and therefore allows very compact filters, which are fully compatible with modern standard CMOS technologies. Besides the saving of chip area, this also helps to reduce parasitic capacitances. The most important advantage of this circuit

Dominique Python; Manfred Punzenberger; Christian C. Enz

1999-01-01

444

Evaluation of Potash Grade with Gamma-ray Logs.  

National Technical Information Service (NTIS)

Potassium is an emitter of gamma-ray radiation, consequently deposits of potash can be detected and evaluated using gamma-ray logs. A method originally designed to evaluate uranium deposits in boreholes can also be applied to potash deposits. The method e...

P. H. Nelson

2007-01-01

445

An economic reliability test plan: Log-logistic distribution  

Microsoft Academic Search

Sampling plans in which items that are put to test, to collect the life of the items in order to decide upon accepting or rejecting a submitted lot, are called reliability test plans. The basic probability model of the life of the product is specified as the well-known log-logistic distribution with a known shape parameter. For a given producer's risk,

R. R. L. Kantam; G. Srinivasa Rao; B. Sriram

2006-01-01

446

EXPONENTIATED LOG-LOGISTIC DISTRIBUTION - AN ECONOMIC RELIABILITY TEST PLAN  

Microsoft Academic Search

The exponentiated log-logistic distribution introduced by Rosaiah et al (2006) is considered as a probability model for the life time of the product. Sampling plans in which items that are put to test, to collect the life of the items in order to decide upon accepting or rejecting a submitted lot, are called reliability test plans. A test plan to

K. Rosaiah; R. R. L. Kantam; Santosh Kumar

2007-01-01

447

Fitting the log-logistic distribution by generalized moments  

Microsoft Academic Search

The method of generalized moments (GM) is investigated for parameter and quantile estimation in the 2-parameter log-logistic (LL2) model. Point estimators for the shape and scale parameters and quantiles are derived. Asymptotic variances and covariances for these estimators are presented, along with simulation results on the performance of the GM method versus the methods of generalized probability weighted moments (GPWM),

Fahim Ashkar; Smail Mahdi

2006-01-01

448

LEP accelerator logging system using on-line database  

NASA Astrophysics Data System (ADS)

The performance and efficiency of LEP depend on a multitude of factors, including particle beam characteristics, physics parameters, hardware settings, and environmental conditions. Often, these factors interact in unexpected ways and affect the machine performance. In January 1992, a project was started to create a unique logging system using an on-line database. One year's worth of data was to be kept on-line, which was estimated to be a total of 8 GByte. The systems concerned are of different nature (particle beam profile, power converter current, meteorological data, magnet temperature, lep-mode, ...), require sampling at different frequencies (from seconds to several hours) and are of different sample size (from 10 MByte to 1 GByte per year). Major performance criteria included rapid logging of data for useful real-time monitoring of compound measurements, and rapid retrieval and correlation of large amounts of data for efficient off-line analysis. For the database design the NIAM methodology was used as well as some interesting techniques such as tagging the rows with timeslots instead of timestamps and row packing for storage minimisation. A complex structure of servers and clients takes care of data gathering, data logging and management of all real time measurement and logging requests. Several tools have been developed to make the data correlation transparent to non-database experts.

Billen, R.; Bordry, F.; Delamare, C.; Hatziangeli, E.; Roeber, F.

1994-12-01

449

Formation evaluation: benefits of downhole logging while drilling  

Microsoft Academic Search

The development of new downhole measurement systems, coupled with mud-pulse telemetry techniques, allows real time surface evaluation of downhole parameters while drilling. Currently available systems, such as Exploration Logging's DLWD tool, combine formation resistivity and natural gamma ray sensors with directional survey and other measurements. These parameters aid formation evaluation, pressure evaluation, well-bore positioning, and drilling efficiency. For real time

J. A. Turvill; G. W. Troy

1983-01-01

450

Analysis of a very large web search engine query log  

Microsoft Academic Search

In this paper we present an analysis of an AltaVista Search Engine query log consisting of approximately 1 billion entries for search requests over a period of six weeks. This represents almost 285 million user sessions, each an attempt to fill a single information need. We present an analysis of individual queries, query duplication, and query sessions. We also present

Craig Silverstein; Hannes Marais; Monika Henzinger; Michael Moricz

1999-01-01

451

Observing the Night Sky --- Observing Logs and Guided Inquiry  

NASA Astrophysics Data System (ADS)

The University of Arizona has initiated a General Education program for all incoming freshmen. All non-science majors must take two introductory Natural Science courses. At the same time the decision was made to eliminate formal labs, but to require instructors to incorporate lab experiences into their Natural Science courses (which typically have 100 to 200 students). For this reason, we have made an Observing Log a major component of our Natural Science class. To make the Log more effective, and to use it as an assessment tool in class, we have incorporated an inquiry-based component. We felt that many observing experiences were ``cookbook'' in nature: make an observation and write down what you saw. Ridgeway and Padilla (The Science Teacher, November 1998) developed what they called Guided Thinking. They proposed ``using three-level thinking guides to promote inquiry in the classroom.'' We have incorporated their procedures into our Observing Log Term Project by having students make a series of guided observations that they can link together with what they have learned in the regular classroom setting. We also take advantage of the Teaching Teams program (peer classroom tutors) so that students can make their observations and discuss them in a small-group setting. A summary of the Observing Log Term Project and examples of student work will be presented.

Lebofsky, L. A.; Lebofsky, N. R.

2000-10-01

452

Log Fano varieties over function fields of curves  

NASA Astrophysics Data System (ADS)

Consider a smooth log Fano variety over the function field of a curve. Suppose that the boundary has positive normal bundle. Choose an integral model over the curve. Then integral points are Zariski dense, after removing an explicit finite set of points on the base curve.

Hassett, Brendan; Tschinkel, Yuri

2008-02-01

453

Policy auditing over incomplete logs: theory, implementation and applications  

Microsoft Academic Search

We present the design, implementation and evaluation of an algorithm that checks audit logs for compliance with privacy and security policies. The algorithm, which we name reduce, addresses two fundamental challenges in compliance checking that arise in practice. First, in order to be applicable to realistic policies, reduce operates on policies expressed in a first-order logic that allows restricted quantification

Deepak Garg; Limin Jia; Anupam Datta

2011-01-01

454

Evaluation of a geothermal well logging, DST and Pit test  

Microsoft Academic Search

This paper briefly discusses logging and testing operations and certain related physical aspects in geothermal well evaluations. A good understanding of thermal and hydrological characteristics of geothermal reservoirs are essential in geothermal well evaluations. Within geothermal reservoirs, in evaluating the wells, the two most important parameters that first could be estimated, then measured or calculated, are temperature and productivity. Well

Tansev; Erdal O

1978-01-01

455

Coarse woody debris in undisturbed and logged forests in the ...  

Treesearch

Title: Coarse woody debris in undisturbed and logged forests in the eastern Brazilian Amazon. ... debris (CWD) is an important component of the carbon cycle in tropical forests. We measured the volume and density of fallen CWD at two sites, Cauaxi and ... CO2 emission given the high rates of decay in moist tropical forests.

456

7. VIEW OF ROLLER FOR EARTH COMPACTING, WITH LOG TONGUE ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. VIEW OF ROLLER FOR EARTH COMPACTING, WITH LOG TONGUE FOR STOCK, BUILT ON-SITE AND USED TO CONSTRUCT DAM, LOOKING EAST - High Mountain Dams in Upalco Unit, Five Point Lake Dam, Ashley National Forest, 12 miles Northwest of Swift Creek Campground, Mountain Home, Duchesne County, UT

457

Assessment of Advanced ESL Students through Daily Action Logs.  

ERIC Educational Resources Information Center

|A classroom study investigated the use of daily action logs as a means for assessing the progress of advanced students of English as a second language (ESL) at the college level. The approach was intended to promote student reflection, help make explicit the class' content, and provide feedback to the teacher on the effectiveness of the…

Vann, Sam

458

Logging of Burned Pines and Rill Erosion in Mediterranean Drylands  

Microsoft Academic Search

We studied the consequences of post-fire logging on rill erosion in six burnt dryland forests in eastern Spain. We selected a range of environmental conditions in order to gain in representativeness for analyzing treatment effect. The experimental sites varied in dominant pine species Pinus halepensis and Pinus pinaster, bedrock and soil types, geomorphic conditions, and stand characteristics such as pine

Angeles Garcia Mayor; Susana Bautista; Charles Darwin; Teresa Gimeno

459

Wireless temperature logging technology for the fishing industry  

Microsoft Academic Search

A system for autonomous temperature logging of fish catches is described. The system is completely wireless and is comprised of a number of loggers, in individual fish boxes, and a base station, assigned to a particular trawler. The temperature of the fish is monitored by the loggers, which contain a thermistor and RF transmitter circuitry. The data is sent at

Karl Crowley; June Frisby; Steve Edwards; Séamus Murphy; Mark Roantree; D. Diamond

2004-01-01

460

Efficient solutions to the replicated log and dictionary problems  

Microsoft Academic Search

We propose efficient algorithms to maintain a replicated dictionary using a log in an unreliable network. A non-serializable approach is used to achieve high concurrency. The solutions are resilient to both node and communication failures. Optimizations are developed for networks which are not completely connected.

Gene T. J. Wuu; Arthur J. Bernstein

1984-01-01

461

A transaction log analysis of a digital library  

Microsoft Academic Search

As experimental digital library testbeds gain wider acceptance and develop significant user bases, it becomes important to investigate the ways in which users interact with the systems in practice. Transaction logs are one source of usage information, and the information on user behaviour can be culled from them both automatically (through calculation of summary statistics) and manually (by examining query

Steve Jones; Sally Jo Cunningham; Rodger J. Mcnab; Stefan J. Boddie

2000-01-01

462

The Detection of Nonfluctuating Targets in Log-Normal Clutter.  

National Technical Information Service (NTIS)

Measurements of sea clutter using high-resolution radar indicate that the clutter-cross-section returns follow a log-normal probability density function more closely than the usually assumed Rayleigh law. This report develops the theory for the detection ...

S. F. George

1968-01-01

463

Facial recognition using partial Log-Polar transformation  

Microsoft Academic Search

Log-Polar transformation is an approximate model of human vision. If using it to recognize human faces, a reference point for the transformation is necessary, and the position of the reference point influences the recognition accuracy directly. However, it is difficult to extract an appropriate reference point from an image automatically. This paper proposes a face recognition method that detects the

Yue Bao; Bin Qi; Fei Gu

2011-01-01

464

Analysis of geophysical logs from the Hawaii geothermal project well  

Microsoft Academic Search

A 6445-foot test well was completed on April 27, 1976 in the Puna Area of Hawaii as part of an extensive project to investigate a geothermal reservoir for energy production. Because bottom hole temperatures exceeded 300°C, it was possible to run geophysical logs in the upper 3500 feet only. Study of conventional and induction resistivity, self potential, neutron, gamma ray,

Rudman

1978-01-01

465

Here is how to calculate pore pressure from logs  

Microsoft Academic Search

Formation pore pressures are calculated by the ratio method (ratio of normal to abnormal resistivity). Overlays are presented to simplify the calculation process. A flow chart is used to show the thought-train used in interpreting the resistivity and conductivity logs. Corrections for Ca\\/sup 2 +\\/ freshwater, and excessive mud weight are discussed. Calculation of salinity from SP is discussed. 11

1971-01-01

466

THE PHYSICAL WORKLOAD OF EMPLOYEES IN LOGGING AND FOREST INDUSTRIES  

Microsoft Academic Search

The efficiency of operations in logging and forest industries can best be increased not through any single means but, rather, by studying the employees' critical workloads in order to achieve a large num- ber of aggregate improvements. Our study focused on finding a better way to reduce the physical stress to workers involved with felling operations and saw-milling in Tanzanian

Dunstan T. K. Shemwetta

467

Snag longevity in relation to wildfire and postfire salvage logging  

Microsoft Academic Search

Snags create nesting, foraging, and roosting habitat for a variety of wildlife species. Removal of snags through postfire salvage logging reduces the densities and size classes of snags remaining after wildfire. We determined important variables associated with annual persistence rates (the probability a snag remains standing from 1 year to the next) of large conifer snags (?23cm diameter breast height

Robin E. Russell; Victoria A. Saab; Jonathan G. Dudley; Jay J. Rotella

2006-01-01

468

The STAR ESL, electronic shift and handover log  

NASA Astrophysics Data System (ADS)

Keeping a clear and accurate experiment log is important for any scientific experiment. The concept is certainly not new but keeping accurate while useful records for a Nuclear Physics experiment such as the Solenoidal Tracker at the Relativistic Heavy Ion Collider (STAR at RHIC) is not a priori a simple matter - STAR operates 24 hours a day for six months out of the year with more than 24 shift crews operating 16 different subsystems (some located remotely). To meet the challenge of not only logging the information but passing it in a concise manner from one shift to another, the STAR experiment has designed an Electronic Shift-Log (ESL), a flexible application written in Java and interfacing with the Data Acquisition tools, Quality Assurance reporting, Online shift crews or remote personnel and experts as well as including features such as shift change-over (or handover) forms, tailored to the sub-group of interest. We will present an overview of STAR's Electronic Log, a system that is clear, reliable, safe, consistent, easy to use and globally viewable in real time with secure connections.

Hajdu, L.; Lauret, J.

2008-07-01

469

Porosity, permeability, and petroleum: Determining the three P's by integrating mud logs with wireline logs and drill-stem tests in central and western Kansas  

Microsoft Academic Search

Mud logging has long been a part of the complete formation evaluation picture in most oil and gas producing provinces of the US. In Kansas, however, mud logging has often been omitted from this picture. Typically, a well in central and western Kansas is drill-stem tested and then logged. Although this technique is often successful, there are also times when

Daniel A. Deboer

1989-01-01

470

Choosing the averaging interval when calculating primary reflection coefficients from well logs  

SciTech Connect

Most seismic data is processed using a sample interval of 4 ms two-way time (twt). The study of the statistical properties of primary reflection coefficients showed that the power spectrum of primaries can change noticeably when the logs are averaged over blocks of 0.5, 1 and 2 ms twt (block-averaging). What is a suitable block-averaging interval for producing broadband synthetics, and in particular how should the power spectrum of primaries be constructed when it is to be used to correct 4 ms sampled deconvolved seismic data for the effects of coloured primary reflectivity. In this paper the authors show that for a typical sonic log, a block-averaging interval of 1 ms twt should satisfy some important requirements. Firstly, it is demonstrated that if the reflection coefficients in an interval are not too large the effect of all the reflection impulses can be represented by another much sparser set at intervals of ..delta..t twt. The coefficient amplitudes are given by the differences in the logarithmic acoustic impedances, thus justifying block-averaging. However, a condition for this to hold up to the aliasing (Nyquist) frequency is that ..delta..t takes a maximum value of about 1 ms twt. Secondly, an event on a log should be represented in the seismic data. For this the acoustic impedance contrast must have sufficient lateral extent or continuity. By making some tentative suggestions on the relation between continuity and bed-thickness, a bed-thickness requirement of 0.15 m or more is obtained. Combining this requirement with the maximum number of beds allowable in an interval in order that multiple reflections do not contribute significantly to the reflections in the interval, again suggests a value of about 1 ms for the block-averaging interval.

Walden, A.T.; Hosken, J.W.J.

1988-11-01

471

a New Application of a Fiber Optic Gyro in Magnetic Borehole Logging  

NASA Astrophysics Data System (ADS)

A borehole magnetometer from the Institute of Geophysics, University of Goettingen, Germany, was employed in Hole 1203A on Detroit Seamount. The tool consists of three fluxgate sensors which log the two horizontal (X, Y) and the vertical (Z) component of the magnetic induction with depth. For the first time, a fiber optic angular rate sensor was employed in a borehole tool to measure the rotation history during a log run in combination with fluxgate sensors. This rate sensor is an unconventional gyro since it does not have a spinning wheel. This is why it is free from the effects of gravity-induced errors, and with no moving parts, this sensor is insensitive to shock and vibration. It detects and measures angular rates by measuring the frequency difference between two contra-rotating light beams. A magnetic log was run in Hole 1203A on Detroit seamount from the rig floor to the total depth at 925 mbsf. The rotation history of the tool is determined by the accumulation of the rate during a log run. In Hole 1203A the tool rotated almost 60 times about its vertical body axis between the rig floor and the bottom of the hole. On its run back to the floor the tool followed nearly the same rotation history as on the downward run. Aligning to the ship axis and double checking the orientation with the initial orientation enabled changes in the heading of the ship and the Earth's rotation, which also affects the angular rate to be taken into account. It revealed that the difference between the initial and final orientation was less than 5 degrees. During the log run many strongly magnetized layers were encountered in the volcanic basement, which correlate well with sequences of massive and pillowed basalts recovered in the drill core. The anomalous field variations of the vertical component always points towards negative values, which indicates a general magnetic polarisation direction parallel to the present geomagnetic field. The natural remanent magnetization and inclination of the formation is obtained by linear inversion of the horizontal and vertical components of the anomalous magnetic field. 16 lava flow units were chosen to estimate the inclination averaged across each unit. The mean inclination is about 44 deg, corresponding to a latitude of 26 degrees, which is clearly different from the present-day latitude of the Hawaii hotspot (19 degrees).

Stoll, J. B.; Leven, M.; Steveling, E.

2002-12-01

472

On generalisations of the log-Normal distribution by means of a new product definition in the Kapteyn process  

NASA Astrophysics Data System (ADS)

We discuss the modification of the Kapteyn multiplicative process using the q-product of Borges [E.P. Borges, A possible deformed algebra and calculus inspired in nonextensive thermostatistics, Physica A 340 (2004) 95]. Depending on the value of the index q a generalisation of the log-Normal distribution is yielded. Namely, the distribution increases the tail for small (when q<1) or large (when q>1) values of the variable upon analysis. The usual log-Normal distribution is retrieved when q=1, which corresponds to the traditional Kapteyn multiplicative process. The main statistical features of this distribution as well as related random number generators and tables of quantiles of the Kolmogorov-Smirnov distance are presented. Finally, we illustrate the validity of this scenario by describing a set of variables of biological and financial origin.

Duarte Queirós, Sílvio M.

2012-07-01

473

Gas Hydrate Research Coring and Downhole Logging Operational Protocol  

NASA Astrophysics Data System (ADS)

Recent gas hydrate deep coring and downhole logging projects, including ODP Leg 204, IODP Expedition 311, and the India NGHP-01 effort have contributed greatly to our understanding of the geologic controls on the occurrence of gas hydrate. These projects have also built on the relatively sparse history of gas hydrate drilling experience to collectively develop a unique operational protocol to examine and sample gas hydrate in nature. The ideal gas hydrate research drill site in recent history, consists of at least three drill holes, with the first hole dedicated to LWD/MWD downhole logging in order to identify intervals to be pressurized cored and to collect critical petrophysical data. The second hole is usually dedicated for continuous coring operations. The third hole is used for special downhole tool measurements such as pressure coring and wire line logging. There is a strong scientific need to obtain LWD/MWD data prior to coring. The coring operations are complemented by frequent deployment of the PCS/HYACINTH pressure core systems. It is essential to know what the gas hydrate concentrations and vertical distribution are before deploying the available pressure core systems in order to choose the optimum depths for pressure coring operations. The coring operations are also complemented by frequent sampling for interstitial water, headspace gas, and microbiological analyses. Although those samples will be taken at relatively regular depths, the sampling frequency can be adjusted if gas hydrate concentrations and distribution can be forward predicted through the analysis of the LWD/MWD pre-core logging surveys. After completing the LWD/MWD logging program, usually as a dedicated drilling leg, field efforts will switch to conventional and pressure-controlled coring operations at each of the sites drilled during the LWD/MWD campaign. The standard continuous core hole will usually include APC coring to an expected refusal depth of ~100 mbsf; each hole is usually advanced to their proposed total depth (TD) by XCB coring. Each of the APC core runs are monitored with the APC-methane (APCM) tool, which in turn is used to analyze and modify gas hydrate core-handling operations. The third hole, or tools hole, will often feature limited APC/XCB coring in intervals with low recovery in the previous continuous core hole and between six to nine PCS/HYACINTH pressure core runs. The tools hole will also be wireline logged (triple combination and FMS-sonic tool strings). Zero-offset VSP surveys have also been added to each site in recent projects.

Collett, T. S.; Riedel, M.; Malone, M.

2006-12-01

474

Log ASCII Standard (LAS) Files for Geophysical (Gamma Ray) Wireline Well Logs and Their Application to Geologic Cross Section C-C' Through the Central Appalachian Basin  

USGS Publications Warehouse

U.S. Geological Survey (USGS) regional geologic cross section C-C' (Ryder and others, 2008) displays key stratigraphic intervals in the central Appalachian basin. For this cross section, strata were correlated by using descriptions of well cuttings and gamma ray well log traces. This report summarizes the procedures used to convert gamma ray curves on paper well logs to the digital Log ASCII (American Standard Code for Information Interchange) Standard (LAS) format using the third-party software application Neuralog. The procedures could be used with other geophysical wireline logs also. The creation of digital LAS files from paper well logs by using Neuralog is very helpful, especially when dealing with older logs with limited or nonexistent digital data. The LAS files from the gamma ray logs of 11 wells used to construct cross section C-C' are included in this report. They may be downloaded from the index page as a single ZIP file.

Trippi, Michael H.; Crangle, Robert D., Jr.

2009-01-01

475

Spatial distribution and partitioning of polychlorinated biphenyls in Tokyo Bay, Japan.  

PubMed

Spatial distributions and partitioning of polychlorinated biphenyls (PCBs) in Tokyo Bay, Japan, were evaluated by measuring the concentrations of all 209 PCB congeners in surface and bottom waters and bottom sediment at 10 locations. The dissolved + particulate summed congener concentrations (SigmaPCB [sum of the concentrations of all 209 PCB congeners]) in surface and bottom waters ranged from 120 to 1100 pg L(-1) (median 250 pg L(-1)) and from 83 to 910 pg L(-1) (median 230 pg L(-1)), respectively. The concentrations did not statistically differ between the two layers, possibly because of vertical mixing of the water column. SigmaPCB concentrations in sediment ranged from 2.7 to 110 ng g(-1)-dry weight. The highest SigmaPCB concentrations in both water and sediment were found at stations in the northern bay. Logarithms of field-observed organic carbon-normalized partition coefficients (K(OC)) increased linearly as the log octanol-water partition coefficients (K(OW)) increased, up to a log K(OW) of about 6.5, and then decreased for log K(OW) > 6.5 (mostly hexa- and hepta-chlorinated biphenyls). Furthermore, log K(OC) values of congeners having log K(OW) < 6.5 were higher by about 1 than values predicted by a published empirically derived equation, suggesting that application of K(OC) values determined in laboratory experiments with soil or sediment samples to fate prediction models may result in overestimation by about one order of magnitude of the concentrations of PCBs with log K(OW) < 6.5 in the dissolved phase in the water column. PMID:20383364

Kobayashi, Jun; Serizawa, Shigeko; Sakurai, Takeo; Imaizumi, Yoshitaka; Suzuki, Noriyuki; Horiguchi, Toshihiro

2010-02-09

476

Universal cable head for a multiconductor logging cable  

SciTech Connect

This patent describes a universal cable head. It comprises: an armored logging cable having up to seven electrical conductors therein and incorporating a woven wire rope, and a surrounding armor wrap; stress relieving stinger means on the cable; an encircling housing to transfer axial loads from the cable to the housing; an internal transverse bulkhead within the housing adjacent to an internal cavity therein; electrical feedthrus for connection of conductors in the logging cable; exposed mating connectors electrically connected to the feedthrus; the housing extending past and encircling the mating connectors; and a rotatable, shoulder limited sleeve on the exterior of the housing having threading means thereon for connecting with a mating female connector.

Ip, M.

1989-10-17

477

Sea clutter contamination test with log-cumulants  

NASA Astrophysics Data System (ADS)

In maritime applications involving estimation of radar sea clutter properties, non-sea-clutter targets and transitions between statistically different oceanographic conditions in the estimation window may lead to inaccurate modeling. Referring to mixtures in the estimation window as contamination, this work introduces a novel sea clutter contamination test based on log-cumulants from Mellin kind statistics [1]. It measures the significant deviation in log-cumulant space due to the contamination, and appears to be an effective tool for improving the sea clutter estimation or to be a direct first-stage target detector. The proposed contamination test is examined with real single look complex (SLC) fine resolution quad-polarimetric Radarsat-2 synthetic aperture radar (SAR) measurements, from the Norwegian Sea, under various oceanographic conditions.

Tao, Ding; Doulgeris, Anthony P.; Brekke, Camilla

2012-09-01

478

Homomorphic processing of the tube wave generated during acoustic logging  

SciTech Connect

The authors have developed a new method to process the tube wave, which is generated during acoustic logging, to obtain estimates for its wavenumber, attenuation coefficient, amplitude, and phase at every frequency. To improve the accuracy of the estimates, the method can use data from multiple sources and data collected at successive depths in the borehole. This new method has several advantages over other methods that are currently used to process acoustic logging data: the new method can obtain accurate estimates of the wavenumber and amplitude from only a few receivers; the receivers can be irregularly spaced; and no spurious estimates are generated. Nonetheless, this new method has one disadvantage compared to others: it can only estimate the parameters for one, high-amplitude wave like the tube wave. Also, like all other existing methods, the new method obtains only reasonable estimates for the attenuation coefficient when data from many receivers are processed.

Ellefsen, K.J. (New England Research Inc., Quincy, MA (United States)); Cheng, C.H. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Earth, Atmospheric, and Planetary Sciences); Burns, D.R.

1993-10-01

479

Slimhole Drilling, Logging, and Completion Technology - An Update  

SciTech Connect

Using slim holes (diameter < 15 cm) for geothermal exploration and small-scale power production can produce significant cost savings compared to conventional rotary-drilling methods. In addition, data obtained from slim holes can be used to lower the risks and costs associated with the drilling and completion of large-diameter geothermal wells. As a prime contractor to the U.S. Department of Energy (DOE), Sandia National Laboratories has worked with industry since 1992 to develop and promote drilling, testing, and logging technology for slim holes. This paper describes the current status of work done both in-house and contracted to industry. It focuses on drilling technology, case histories of slimhole drilling projects, data collection and rig instrumentation, and high-temperature logging tools.

FINGER,JOHN T.; JACOBSON,RONALD D.

1999-10-07

480

Geophysical characterization of the Lollie Levee near Conway, Arkansas, using capacitively coupled resistivity, coring, and direct push logging  

USGS Publications Warehouse

A geophysical characterization of Lollie Levee near Conway, Arkansas, was conducted in February 2011. A capacitively coupled resistivity survey (using Geometric's OhmMapper) was completed along the top and toe of the 6.7-mile levee. Two-dimensional inversions were conducted on the geophysical data. As a quality-control measure, cores and direct push logs were taken at approximately 1-mile intervals along the levee. The capacitively coupled resistivity survey, the coring, and the direct push logs were used to characterize the geologic materials. Comparison of the cores and the direct push log data, along with published resistivity values, indicates that resistivity values of 200 Ohm-meters or greater represent relatively clean sand, with decreasing resistivity values occurring with increasing silt and clay content. The cores indicated that the levee is composed of a heterogeneous mixture of sand, silt, and clay. The capacitively coupled resistivity sections confirm that the levee is composed of a heterogeneous mixture of high and low resistivity materials and show that the composition of the levee varies spatially. The geologic materials underlying the levee vary spatially as a result of the geologic processes that deposited them. In general, the naturally deposited geologic materials underlying the levee contain a greater amount of low resistivity materials in the southern extent of the levee.

Gillip, Jonathan A.; Payne, Jason D.

2011-01-01

481

A Log-Structured Organization for Tertiary Storage  

Microsoft Academic Search

We present the design of a log-structured tertiarystorage system (LTS). The advantage of this approachis that it allows the system to hide the details of jukeboxrobotics and media characteristics behind a uniform,random access, block-oriented interface. It alsoallows the system to avoid media mount operations forwrites, giving write performance similar to that of secondarystorage.1 IntroductionIn this paper, we argue for a

Daniel Alexander Ford; Jussi Myllymaki

1996-01-01

482

Porosity and Pore Structure from Acoustic Well Logging DATA1  

Microsoft Academic Search

Wyllie's time-average equation and subsequent refinements have been used for over 20 years to estimate the porosity of reservoir rocks from compressional (P)-wave velocity (or its reciprocal, transit time) recorded on a sonic log. This model, while simple, needs to be more convincingly explained in theory and improved in practice, particularly by making use of shear, (S)-wave velocity. One of

G. Tao; M. S. King

1993-01-01

483

Uranium logging by the prompt fission neutron technique  

Microsoft Academic Search

This paper briefly describes the Sandia prompt fission neutron uranium