These are representative sample records from Science.gov related to your search topic.
For comprehensive and current results, perform a real-time search at Science.gov.
1

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 19years 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

2

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...

3

Urban Wood Waste: Maximizing Log Value for the Sawmill Market David T. Damery, Lecturer  

E-print Network

Urban Wood Waste: Maximizing Log Value for the Sawmill Market David T. Damery, Lecturer Brian C.P. Kane, Asst. Professor, Univ. of Massachusetts, Amherst, MA How arborists view the issue of "waste wood facilities are rising continually. Disposing of waste wood was once merely a time and labor factor, but now

Schweik, Charles M.

4

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

5

The WeightedLog-RankClass of Permutation Tests: P-values andConfidence 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 permu- tation distributions of tests from the weighted log-rank class. Analytical saddlepoint computations replace the permutation simulations and pro- vide mid-p-values that are virtually exact for all practical purposes.

Ehab F. Abd-Elfattah; Ronald W. Butler

6

Fitting LogF Models Robustly, with an Application to the Analysis of Extreme Values  

E-print Network

usually used to model probability of response at a given dosage. Prentice (1975) used this parametric in calculating log­likelihoods and their derivatives impeded the growth in popularity of this four­ parameter for these calculations. The actual fitting of the model to the data is still not trivial however, and applications

Dupuis, Debbie

7

The weighted log-rank class under truncated binomial design: saddlepoint p-values and confidence intervals.  

PubMed

The randomization design used to collect the data provides basis for the exact distributions of the permutation tests. The truncated binomial design is one of the commonly used designs for forcing balance in clinical trials to eliminate experimental bias. In this article, we consider the exact distribution of the weighted log-rank class of tests for censored data under the truncated binomial design. A double saddlepoint approximation for p-values of this class is derived under the truncated binomial design. The speed and accuracy of the saddlepoint approximation over the normal asymptotic facilitate the inversion of the weighted log-rank tests to determine nominal 95% confidence intervals for treatment effect with right censored data. PMID:22009338

Abd-Elfattah, Ehab F

2012-04-01

8

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...

9

Dominating Set Based and PowerDominating Set Based and Power--aware Hierarchical Epidemics in P2P Systemsaware Hierarchical Epidemics in P2P Systems Tugba KocTugba Koc Emrah CemEmrah Cem Oznur OzkasapOznur Ozkasap  

E-print Network

Dominating Set Based and PowerDominating Set Based and Power--aware Hierarchical Epidemics in P2P Systemsaware Hierarchical Epidemics in P2P Systems Tugba KocTugba Koc Emrah CemEmrah Cem Oznur Ozkasap Turkey Introduction Epidemic (gossip-based) principles: highly popular in Dominating Set Based and Power

?zkasap, ?znur

10

VARIATION OF KOC IN SURFACE SEDIMENTS FROM NARRAGANSETT BAY AND LONG ISLAND SOUND: ANALYSIS OF THE ROLE OF OTHER PARTICULATE CHARACTERISTICS  

EPA Science Inventory

In the first part of this investigation, we examined whether differences in the Kocs of three nonpolar organic chemicals (Lindane, fluoranthene, tetrachlorinated biphenyl (PCB)) from five sites along the New England coast were statistically significant. Although no statistical di...

11

Well Logs  

NSDL National Science Digital Library

This activity provides students with three fundamental borehole geophysics experiences using real data -- correlating, mapping, and logging. Students are asked to correlate well logs and construct maps and cross-sections based on that information. Students are also asked to construct a "mud log" from actual drill cuttings and compare their interpretation to that from a borehole geophysics log. This activity as minimal/no quantitative component.

Brewer, Kevin

12

The RP-HPLC measurement and QSPR analysis of logP(o/w) values of several Pt(II) complexes.  

PubMed

The n-octanol/water partition coefficient, logP(o/w), for a set of 24 Pt(II)-complexes was estimated by means of reversed-phase high performance liquid chromatography (RP-HPLC) technique using a C18 (ODS, octadecyl silane) column as a stationary phase and water/methanol mixtures as mobile phases. Based on the known logP(o/w) of several Pt(II)-complexes, we set a method to correlate the partition coefficient of this kind of complexes with the corresponding retention parameters. The best result was obtained from extrapolation to 0% of the organic modifier (MeOH) of the aqueous eluant. A quantitative structure-property relationship (QSPR) was constructed using molecular descriptors derived from density functional theory (DFT) calculations, which was found to correlate and predict these values with good accuracy. The use of DFT calculations is required because group-additive methods fail due to lack of values for appropriate fragments for many Pt(II)-complexes. PMID:16530269

Platts, James A; Oldfield, Steven P; Reif, Maria M; Palmucci, Alessandra; Gabano, Elisabetta; Osella, Domenico

2006-07-01

13

Improved V II Log(gf) Values, Hyperfine Structure Constants, and Abundance Determinations in the Photospheres of the Sun and Metal-poor Star HD84937  

NASA Astrophysics Data System (ADS)

New experimental absolute atomic transition probabilities are reported for 203 lines of V II. Branching fractions are measured from spectra recorded using a Fourier transform spectrometer and an echelle spectrometer. The branching fractions are normalized with radiative lifetime measurements to determine the new transition probabilities. Generally good agreement is found between this work and previously reported V II transition probabilities. Two spectrometers, independent radiometric calibration methods, and independent data analysis routines enable a reduction in systematic uncertainties, in particular those due to optical depth errors. In addition, new hyperfine structure constants are measured for selected levels by least squares fitting line profiles in the FTS spectra. The new V II data are applied to high resolution visible and UV spectra of the Sun and metal-poor star HD 84937 to determine new, more accurate V abundances. Lines covering a range of wavelength and excitation potential are used to search for non-LTE effects. Very good agreement is found between our new solar photospheric V abundance, log ?(V) = 3.95 from 15 V II lines, and the solar-system meteoritic value. In HD 84937, we derive [V/H] = 2.08 from 68 lines, leading to a value of [V/Fe] = 0.24.

Wood, M. P.; Lawler, J. E.; Den Hartog, E. A.; Sneden, C.; Cowan, J. J.

2014-10-01

14

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

15

Thermal conditions of the central Sinai Microplate inferred from new surface heat-flow values and continuous borehole temperature logging in central and southern Israel  

NASA Astrophysics Data System (ADS)

This paper reports ten new surface heat-flow density (qs) values for central and southern Israel (central Sinai Microplate), whose crystalline crust and lithosphere formed as part of the Neoproterozoic Arabian-Nubian Shield. Heat flow was calculated in Mesozoic sediments using the classical approach of heat-flow determination by implementing in the analysis high-precision continuous temperature logs obtained in air- and/or water-filled boreholes. Thermal conductivity (TC) measured for a large suite of rock samples of lithotypes making up the sequence was assigned to temperature gradients in intervals for which the lithology was known. The heat-flow values obtained for different depth intervals in a borehole as well as the average values for the individual borehole locations cover a narrow range, attesting heat-conduction conditions. A steady-state thermal model along an E-W crustal cross section through the area shows that the observed systematic spatial distribution of the qs values, which range between 50 and 62 mW m-2, can primarily be explained by variations in the thickness of the upper crust and in the ratio between sedimentary and crystalline rocks therein. Given the time lapse of thermal heat transfer through the lithosphere, the qs data monitor the crustal thermal conditions prior to rift- and plume-related lithospheric thermal perturbations that have started in the larger area ca. 30 Ma ago. Observed and modeled qs display the best fit for a pre-Oligocene lithosphere-asthenosphere boundary (LAB) at 150 km, which would be at the upper end of LAB depths determined from stable areas of the Arabian Shield (150-120 km) not affected by the young, deep-seated thermal processes that have caused a further uprise of the LAB. Our data imply or predict that the surface heat flow of the Sinai Microplate generally tends to increase along N-S and W-E traverses, from 45-50 mW m-2 to 55-60 mW m-2. Surface heat flows on the order of 55-60 mW m-2 may be common in the northern Arabian Shield, where it exhibits typical lithosphere structure and composition and is unaffected by young heating processes, compared to values of ?45 mW m-2 recently determined in the southern Arabian Plate for the Arabian Platform.

Schtz, F.; Frster, H.-J.; Frster, A.

2014-05-01

16

3.0 Methods, Issues, and Criteria for Measuring Kd Values There are 5 general methods used to measure Kd values: the batch laboratory method, laboratory  

E-print Network

on the soil. Thus, use of Kd values determined from batch adsorption tests in contaminant transport models-batch method, field modeling method, and Koc method. These methods and the associated technical issues ments is that they do not accurately simulate desorption of the radionuclides or contaminants from

17

CRYPTOSPORIDIUM LOG INACTIVATION CALCULATION METHODS  

EPA Science Inventory

Appendix O of the Surface Water Treatment Rule (SWTR) Guidance Manual introduces the CeffT10 (i.e., reaction zone outlet C value and T10 time) method for calculating ozone CT value and Giardia and virus log inactivation. The LT2ESWTR Pre-proposal Draft Regulatory Language for St...

18

Ecological Importance of Submerged Pulpwood Logs in a Maine Reservoir  

Microsoft Academic Search

Log drives in Maine from the 1830s to 1976 left an estimated 3.67.2 10 m of pulpwood logs submerged in the Kennebec River system, principally in Wyman Lake and Indian Pond. Because favorable economics have led to commercial log salvaging, we assessed the ecological value of submerged pulpwood logs in Wyman Lake. Three species of fishes, longnose suckers Catostomus

John R. Moring; Paul D. Eiler; Mary T. Negus; Elizabeth Gibbs

1986-01-01

19

LogScope  

NASA Technical Reports Server (NTRS)

LogScope is a software package for analyzing log files. The intended use is for offline post-processing of such logs, after the execution of the system under test. LogScope can, however, in principle, also be used to monitor systems online during their execution. Logs are checked against requirements formulated as monitors expressed in a rule-based specification language. This language has similarities to a state machine language, but is more expressive, for example, in its handling of data parameters. The specification language is user friendly, simple, and yet expressive enough for many practical scenarios. The LogScope software was initially developed to specifically assist in testing JPL s Mars Science Laboratory (MSL) flight software, but it is very generic in nature and can be applied to any application that produces some form of logging information (which almost any software does).

Havelund, Klaus; Smith, Margaret H.; Barringer, Howard; Groce, Alex

2012-01-01

20

Methods of generating synthetic acoustic logs from resistivity logs for gas-hydrate-bearing sediments  

USGS Publications Warehouse

Methods of predicting acoustic logs from resistivity logs for hydrate-bearing sediments are presented. Modified time average equations derived from the weighted equation provide a means of relating the velocity of the sediment to the resistivity of the sediment. These methods can be used to transform resistivity logs into acoustic logs with or without using the gas hydrate concentration in the pore space. All the parameters except the unconsolidation constants, necessary for the prediction of acoustic log from resistivity log, can be estimated from a cross plot of resistivity versus porosity values. Unconsolidation constants in equations may be assumed without rendering significant errors in the prediction. These methods were applied to the acoustic and resistivity logs acquired at the Mallik 2L-38 gas hydrate research well drilled at the Mackenzie Delta, northern Canada. The results indicate that the proposed method is simple and accurate.

Lee, Myung W.

1999-01-01

21

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

22

Teff log g nHe Teff log g A  

E-print Network

#12;#12;B Teff log g nHe Teff log g nHe Teff + #12;#12;#12;#12;#12;#12;2 #12;+ #12;#12;Teff #12;+ °A + + #12;+ Teff log g °A log g - Teff log g - Teff #12;- + + + + log g - Teff #12;#12;Teff #12; 10 #12; 8 #12; 6 -2 4 3 8 9 ? 10 #12;#12;g nHe n

23

Autoantibody detection to tumor-associated antigens of P53, IMP1, P16, cyclin B1, P62, C-myc, Survivn, and Koc for the screening of high-risk subjects and early detection of esophageal squamous cell carcinoma.  

PubMed

The aim of this study was to evaluate the diagnostic values by detecting sera autoantibodies to eight tumor-associated antigens (TAAs) of P53, IMP1, P16, cyclin B1, P62, C-myc, Survivn and Koc full-length recombinant proteins for the screening of high-risk subjects and early detection of esophageal squamous cell carcinoma (ESCC). Enzyme-linked immunosorbent assay was used to detect autoantibodies against the eight selected TAAs in 567 sera samples from four groups, including 200 individuals with normal esophageal epithelia (NOR), 214 patients with esophageal basal cell hyperplasia (BCH), 65 patients with esophageal dysplasia (DYS), and 88 patients with ESCC. In addition, the expression of the eight antigens in esophageal tissues was analyzed by immunohistochemistry. Statistically significant distribution differences were identified among the four groups for each of the individual autoantibodies to six TAAs (P53, IMP1, P16, cyclin B1, P62, and C-myc); the detection rates of antoantibodies were positively correlated with the progression of ESCC. When autoantibody assay successively accumulated to six TAAs (P53, IMP1, P16, cyclin B1, P62, and C-myc), a stepwise increased detection frequency of autoantibodies was found in the four sera groups (6% in NOR, 18% in BCH, 38% in DYS, and 64% in ESCC, respectively), the risks to BHC, DYS, and ESCC steadily increased about 3-, 9-, and 27-folds. The sensitivity and the specificity for autoantibodies against the six TAAs in diagnosing ESCC reached up to 64% and 94%, respectively. The area under the receiver operating characteristic curve for the six anti-TAA autoantibodies was 0.78 (95% confidence interval 0.74-0.83). No more increasing in sensitivity was found with the addition of new anti-TAA autoantibodies. A combination detection of autoantibodies to TAAs might distinguish ESCC patients from normal individuals and the patients with esophageal precancerous lesions. PMID:24147952

Zhou, S L; Yue, W B; Fan, Z M; Du, F; Liu, B C; Li, B; Han, X N; Ku, J W; Zhao, X K; Zhang, P; Cui, J; Zhou, F Y; Zhang, L Q; Fan, X P; Zhou, Y F; Zhu, L L; Liu, H Y; Wang, L D

2014-11-01

24

Log periodic dipole arrays  

Microsoft Academic Search

A new class of coplanar dipole arrays is introduced. The antennas described provide unidirectional radiation patterns of constant beamwidth and nearly constant input impedances over any desired bandwidth. The broad-band properties are achieved by making use of the principles of log periodic antenna design. Models are discussed which are capable of providing 8- to 9-db directive gain with an associated

D. Isbell

1960-01-01

25

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.

26

,"_' ",',-i_~ :FORESTRY AND LOGGING  

E-print Network

":~I> ", .' '. ,"_' ",',-i_~ . :FORESTRY AND LOGGING Hcscarch on Plantation Species A Positive in plantation forestry. par- ticularly in the tropics and the Southern Hemisphere. in the past 30 years plantation forestry. Indeed, one could list many exam- ples of such problems that have plagued exotic

27

12. Upstream view showing thelower log pond log chute in ...  

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

12. Upstream view showing thelower log pond log chute in the main channel of the Hudson River. The log chute in the dam can be seen in the background. Facing southwest. - Glens Falls Dam, 100' to 450' West of U.S. Route 9 Bridge Spanning Hudson River, Glens Falls, Warren County, NY

28

Information Security Office Logging Standard  

E-print Network

Information Security Office Logging Standard #12;Logging Standard 1 | P a g e Revision History Revision Date Revised By Summary of Revisions Section(s) / Page(s) Revised 6/01/2013 ISO Initial Release Pufahl, CISO Approved 6/01/2013 RMAC Risk Management Advisory Council Reviewed #12;Logging Standard 2 | P

Alpay, S. Pamir

29

Dipole shear anisotropy logging  

SciTech Connect

Sonic-scale shear anisotropy of formations are obtained from dipole-shear measurements acquired by orthogonal source and receiver pairs. These measurements resemble miniature 4-component shear VSP surveys inside the borehole. Data from two orthogonal sources and an array of orthogonal receivers are processed providing three main logs; the fast and slow shear slownesses, and the fast shear polarization angle. Potential applications include: shale anisotropy for better seismic models, maximum stress and fracture/microcrack strike direction for horizontal well drilling and fracture height and azimuth determination in hydraulic fracturing.

Esmersoy, C.; Kane, M. [Schlumberger-Doll Research, Ridgefield, CT (United States); Koster, K.; Williams, M. [Amoco Production, Denver, CO (United States); Boyd, A. [GeoQuest, Aurora, CO (United States)

1994-12-31

30

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

31

Borehole compensated KUT log  

SciTech Connect

A method of logging earth formations to ascertain relative elemental abundances of potassium (K), uranium (U) and thorium (T) is disclosed. A natural gamma ray spectrum of an unknown borehole is compared with individual standard gamma ray spectra of potassium, uranium and thorium in at least four energy ranges or bands. Decay peaks of the three elements are encompassed by three of the energy bands and at least one other energy band is used to monitor the changes in shape of the unknown spectrum caused by borehole conditions differing from that of the standard or calibration boreholes. A function derived from the gamma ray count rates in the four bands is used to compensate the elemental abundances of the three elements to be detected in the unknown spectrum for the effects of differing borehole conditions in the unknown borehole from the standard borehole conditions.

Arnold, D.M.; Schultz, W.E.; Smith, H.D. Jr.

1984-03-13

32

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

33

Data Encryption Standard Cetin Kaya Koc  

E-print Network

as an official Federal Information Processing Standard (FIPS) for the United States in 1977, with the number FIPS (1915-1990) was a German-born cryptographer who worked on the design of ciphers at IBM, initiating research that gave birth to the Data Encryption Standard (DES) in the 1970s Feistel was one of the earliest

34

Terminology Extraction from Log Files  

NASA Astrophysics Data System (ADS)

The log files generated by digital systems can be used in management information systems as the source of important information on the condition of systems. However, log files are not exhaustively exploited in order to extract information. The classical methods of information extraction such as terminology extraction methods are irrelevant to this context because of the specific characteristics of log files like their heterogeneous structure, the special vocabulary and the fact that they do not respect a natural language grammar. In this paper, we introduce our approach Exterlog to extract the terminology from log files. We detail how it deals with the particularity of such textual data.

Saneifar, Hassan; Bonniol, Stphane; Laurent, Anne; Poncelet, Pascal; Roche, Mathieu

35

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

36

G8 Illegal Logging Dialogue G8 Illegal Logging Dialogue  

E-print Network

representatives · agree practical policy actions to address illegal logging and sustainable forest management and sustainable forestry Reaching out to Chinese legislators China and the Global Forest Products Trade Trade governments #12;G8 Illegal Logging Dialogue · legislators from: ­ all G8 countries ­ Brazil ­ Cameroon ­ China

37

Logging concessions enable illegal logging crisis in the Peruvian Amazon.  

PubMed

The Peruvian Amazon is an important arena in global efforts to promote sustainable logging in the tropics. Despite recent efforts to achieve sustainability, such as provisions in the US-Peru Trade Promotion Agreement, illegal logging continues to plague the region. We present evidence that Peru's legal logging concession system is enabling the widespread illegal logging via the regulatory documents designed to ensure sustainable logging. Analyzing official government data, we found that 68.3% of all concessions supervised by authorities were suspected of major violations. Of the 609 total concessions, nearly 30% have been cancelled for violations and we expect this percentage to increase as investigations continue. Moreover, the nature of the violations indicate that the permits associated with legal concessions are used to harvest trees in unauthorized areas, thus threatening all forested areas. Many of the violations pertain to the illegal extraction of CITES-listed timber species outside authorized areas. These findings highlight the need for additional reforms. PMID:24743552

Finer, Matt; Jenkins, Clinton N; Sky, Melissa A Blue; Pine, Justin

2014-01-01

38

Acoustic paramagnetic logging tool  

DOEpatents

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

39

Interpretation of geophysical well logs in permafrost. Final report  

SciTech Connect

This report is a collection of information on the interpretation of well logs and borehole geophysical surveys in permafrost. The body of the report is preceded by an executive summary that gives the highlights of the report in condensed form. The introductory chapter contains background information that is fundamental to the understanding of well log applications in permafrost, including definitions and descriptions of well logs, permafrost, and related terms, and illustrations showing the extent of permafrost in Alaska. Chapter 2 presents information on physical properties of permafrost that relate to well log interpretation, including porosity and pore-filling media (water, ice and air), and their effects on thermal properties, electrical properties and acoustic properties. Chapters 3-8 describe the following types of well logs in detail, including measurement principles and methods, procedures for calibration and interpretation, and identification of special problems relatd to permafrost: thermal logs, electric logs, sonic logs, nuclear logs, magnetic logs, and miscellaneous (caliper and drilling) logs. Chapter 9 gives information on three types of borehole geophysical surveys, electrical resistivity, seismic velocity, and borehole gravity, with emphasis on the increased depth of investigation afforded by these surveys as compared with well logs. Chapter 10 describes a number of specific applications. A concluding chapter summariezes the information contained in the body of the report and includes a table that gives an overview of the relative value of various borehole geophysical measurements that can be used for delineating and characterizing permafrost. Conclusions of the report are that a number of standard borehole measurement techniques have been tried and proven in permafrost and can be used effectively to delineate and characterize earth material penetrated by the borehole. 19 figs., 8 tabs.

Scott, J.H.; Petersen, J.K.; Osterkamp, T.E.; Kawasaki, K.

1986-01-01

40

Chapter XXV Web Log Analysis  

E-print Network

504 Chapter XXV Web Log Analysis: Diversity Of Research Methodologies Isak Taksa City University these methodologies, and propose directions for future research in the field of Web log analysis. rEsEArcH MEtHODOLOGIEs of phenomenology, examines individual and group interactions within a social structure. · Content Analysis

Jansen, James

41

Estimating thermal conductivity from core and well log data  

NASA Astrophysics Data System (ADS)

The aim of the presented work was to introduce a method of estimating thermal conductivity using well log data. Many petrophysical properties of rocks can be determined both by laboratory measurements and well-logs. It is thus possible to apply geophysical data to empirical models based on relationships between laboratory measured parameters and derive continuous thermal conductivity values in well profiles. Laboratory measurements were conducted on 62 core samples of Meso-Paleozoic rocks from the Carpathian Foredeep. Mathematical models were derived using multiple regression and neural network methods. Geophysical data from a set of seven well logs: density, sonic, neutron, gamma ray, spectral gamma ray, caliper and resistivity were applied to the obtained models. Continuous thermal conductivity values were derived in three well profiles. Analysis of the obtained results shows good consistence between laboratory data and values predicted from well log data.

G?sior, Irena; Przelaskowska, Anna

2014-08-01

42

Maintaining ecosystem function and services in logged tropical forests.  

PubMed

Vast expanses of tropical forests worldwide are being impacted by selective logging. We evaluate the environmental impacts of such logging and conclude that natural timber-production forests typically retain most of their biodiversity and associated ecosystem functions, as well as their carbon, climatic, and soil-hydrological ecosystem services. Unfortunately, the value of production forests is often overlooked, leaving them vulnerable to further degradation including post-logging clearing, fires, and hunting. Because logged tropical forests are extensive, functionally diverse, and provide many ecosystem services, efforts to expand their role in conservation strategies are urgently needed. Key priorities include improving harvest practices to reduce negative impacts on ecosystem functions and services, and preventing the rapid conversion and loss of logged forests. PMID:25092495

Edwards, David P; Tobias, Joseph A; Sheil, Douglas; Meijaard, Erik; Laurance, William F

2014-09-01

43

Noise-induced phase slips, log-periodic oscillations, and the Gumbel distribution  

E-print Network

Noise-induced phase slips, log-periodic oscillations, and the Gumbel distribution Nils Berglund on the phenomenon of log-periodic oscillations and on links between transition path theory and extreme-value theory, ran- dom Poincar´e map, log-periodic oscillations, cycling, transition-path theory, extreme

Paris-Sud XI, Université de

44

Quantitative Generalizations for Catchment Sediment Yield Following Plantation Logging  

NASA Astrophysics Data System (ADS)

While there is a reasonably clear qualitative understanding of the impact of forest plantations on sediment yield, there is a lack of quantitative generalizations. Such generalizations would be helpful for estimating the impacts of proposed forestry operations and would aid the spread of knowledge amongst both relevant professionals and new students. This study therefore analyzed data from the literature to determine the extent to which quantitative statements can be established. The research was restricted to the impact of plantation logging on catchment sediment yield as a function of ground disturbance in the years immediately following logging, in temperate countries, and does not consider landslides consequent upon tree root decay. Twelve paired catchment studies incorporating pre- and post-logging measurements of sediment yield were identified, resulting in forty-three test catchments (including 14 control catchments). Analysis yielded the following principal conclusions: 1) Logging generally provokes maximum annual sediment yields of less than a few hundred t km-2 yr-1; best management practice can reduce this below 100 t km-2 yr-1. 2) At both the annual and event scales, the sediment yield excess of a logged catchment over a control catchment is within one order of magnitude, except with severe ground disturbance. 3) There is no apparent relationship between sediment yield impact and the proportion of catchment logged. The effect depends on which part of the catchment is altered and on its connectivity to the stream network. 4) The majority of catchments delivered their maximum sediment yield in the first two years after logging. The logging impacts were classified in terms of the absolute values of specific sediment yield, the values relative to those in the control catchments for the same period and the values relative both to the control catchment and the pre-logging period. Most studies have been for small catchments (< 10 km2) and temperate regions; the impact at large catchment scales and in tropical regions requires further research.

Bathurst, James; Iroume, Andres

2014-05-01

45

No chiral truncation of quantum log gravity?  

E-print Network

At the classical level, chiral gravity may be constructed as a consistent truncation of a larger theory called log gravity by requiring that left-moving charges vanish. In turn, log gravity is the limit of topologically massive gravity (TMG) at a special value of the coupling (the chiral point). We study the situation at the level of linearized quantum fields, focussing on a unitary quantization. While the TMG Hilbert space is continuous at the chiral point, the left-moving Virasoro generators become ill-defined and cannot be used to define a chiral truncation. In a sense, the left-moving asymptotic symmetries are spontaneously broken at the chiral point. In contrast, in a non-unitary quantization of TMG, both the Hilbert space and charges are continuous at the chiral point and define a unitary theory of chiral gravity at the linearized level.

Tomas Andrade; Donald Marolf

2009-09-03

46

New materials for fireplace logs  

NASA Technical Reports Server (NTRS)

Fibrous insulation and refractory concrete are used for logs as well as fireproof walls, incinerator bricks, planters, and roof shingles. Insulation is lighter and more shock resistant than fireclay. Lightweight slag bonded with refractory concrete serves as aggregrate.

Kieselback, D. J.; Smock, A. W.

1971-01-01

47

Logs help approximate reservoir temperature  

SciTech Connect

Parameters have been studied to better understand and analytically describe temperature distribution in well bores. Some of these parameters include: fluid temperature behavior in the borehole during well tripping; BHT while drilling; temperature profile over the entire borehole; and determination of true formation temperature from geophysical wire line logging devices. The technique presented in this article corrects open hole log temperatures to true formation temperature.

Fertl, W.H.

1985-04-29

48

BSP versus LogP  

Microsoft Academic Search

. A quantitative comparison of the BSP and LogP models of parallel computation is developed. We concentrate on a variant of\\u000a LogP that disallows the so-called stalling behavior, although issues surrounding the stalling phenomenon are also explored.\\u000a Very efficient cross simulations between the two models are derived, showing their substantial equivalence for algorithmic\\u000a design guided by asymptotic analysis. It

Gianfranco Bilardi; Andrea Pietracaprina; Geppino Pucci; Kieran T. Herley; Paul G. Spirakis

1999-01-01

49

Solution of Maxwell's equations for log-periodic dipole antennas  

Microsoft Academic Search

A theory of the log-periodic dipole antenna, which is a solution of the antenna boundary-value problem, is presented here. The theory is derived from Maxwell's equations by solving the wave equation in cylindrical coordinates and satisfying all boundary conditions. The theory is not limited to the log-periodic dipole antenna, but can be easily modified and applied to other antenna configurations

JOACHIAI WOLTER

1970-01-01

50

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

51

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

52

The Dry Eye Disease Activity Log Study  

PubMed Central

Prolonged visually stressful activities aggravate dry eye disease (DED). The duration spent on such activities and their relationship with DED clinical features were investigated. Patients completed an activity log as they performed their usual activities over 1 typical rest day and 1 typical work day. The log included time spent in an air-conditioned environment, windy environment, driving, watching television, computer use, reading, watching a movie in the theatre, and wearing contact lens. Average daily activity hours were calculated and correlated with clinical features of DED. Thirty-five logs were returned. Positive correlation was found between watching television and episodic blurred vision (P < 0.01). Computer use was negatively correlated with episodic blur vision, burning sensation, and gritty sensation (P < 0.05). Negative correlation was found between time spent in windy environments, driving, reading, and certain DED symptoms (P < 0.05). Reading correlated positively with severity of corneal fluorescein staining and reduced Schirmer's values (P < 0.03). The use of air conditioning correlated negatively with episodic blur vision but positively with visual blurring that improves with lubricants (P = 0.02). This study is the first to evaluate the relationship between time spent on DED-aggravating activities and DED clinical features. Negative correlations between certain activities and DED symptoms suggest an unconscious modification of lifestyle to alleviate symptoms. PMID:23193384

Iyer, Jayant V.; Lee, Sze-Yee; Tong, Louis

2012-01-01

53

The dry eye disease activity log study.  

PubMed

Prolonged visually stressful activities aggravate dry eye disease (DED). The duration spent on such activities and their relationship with DED clinical features were investigated. Patients completed an activity log as they performed their usual activities over 1 typical rest day and 1 typical work day. The log included time spent in an air-conditioned environment, windy environment, driving, watching television, computer use, reading, watching a movie in the theatre, and wearing contact lens. Average daily activity hours were calculated and correlated with clinical features of DED. Thirty-five logs were returned. Positive correlation was found between watching television and episodic blurred vision (P < 0.01). Computer use was negatively correlated with episodic blur vision, burning sensation, and gritty sensation (P < 0.05). Negative correlation was found between time spent in windy environments, driving, reading, and certain DED symptoms (P < 0.05). Reading correlated positively with severity of corneal fluorescein staining and reduced Schirmer's values (P < 0.03). The use of air conditioning correlated negatively with episodic blur vision but positively with visual blurring that improves with lubricants (P = 0.02). This study is the first to evaluate the relationship between time spent on DED-aggravating activities and DED clinical features. Negative correlations between certain activities and DED symptoms suggest an unconscious modification of lifestyle to alleviate symptoms. PMID:23193384

Iyer, Jayant V; Lee, Sze-Yee; Tong, Louis

2012-01-01

54

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

Microsoft Academic Search

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

S. Drozdz; F. Grmmer; F. Ruf; J. Speth

2003-01-01

55

Mail LOG: Program operating instructions  

NASA Technical Reports Server (NTRS)

The operating instructions for the software package, MAIL LOG, developed for the Scout Project Automatic Data System, SPADS, are provided. The program is written in FORTRAN for the PRIME 300 computer system. The MAIL LOG program has the following four modes of operation: (1) INPUT - putting new records into the data base (2) REVISE - changing or modifying existing records in the data base (3) SEARCH - finding special records existing in the data base (4) ARCHIVE - store or put away existing records in the data base. The output includes special printouts of records in the data base and results from the INPUT and SEARCH modes. The MAIL LOG data base consists of three main subfiles: Incoming and outgoing mail correspondence; Design Information Releases and Releases and Reports; and Drawings and Engineering orders.

Harris, D. K.

1979-01-01

56

Log amplifier with pole-zero compensation  

DOEpatents

A logarithmic amplifier circuit provides pole-zero compensation for improved stability and response time over 6-8 decades of input signal frequency. The amplifier circuit includes a first operational amplifier with a first feedback loop which includes a second, inverting operational amplifier in a second feedback loop. The compensated output signal is provided by the second operational amplifier with the log elements, i.e., resistors, and the compensating capacitors in each of the feedback loops having equal values so that each break point or pole is offset by a compensating break point or zero.

Brookshier, William (Downers Grove, IL)

1987-01-01

57

Log amplifier with pole-zero compensation  

DOEpatents

A logarithmic amplifier circuit provides pole-zero compensation for improved stability and response time over 6-8 decades of input signal frequency. The amplifer circuit includes a first operational amplifier with a first feedback loop which includes a second, inverting operational amplifier in a second feedstock loop. The compensated output signal is provided by the second operational amplifier with the log elements, i.e., resistors, and the compensating capacitors in each of the feedback loops having equal values so that each break point is offset by a compensating break point or zero.

Brookshier, W.

1985-02-08

58

Logging in a computational steering environment  

Microsoft Academic Search

Logging of input and output variables is very useful in computational steering. In this paper we describe how we added logging functionality to a computational steering environment developed at CWI. We show how a 2D interface can be augmented with logging by using the third dimension for the display of the logged variables. The user specifies which graphical representations of

Jurriaan D. Mulder; Jarke J. van Wijk

1995-01-01

59

LogKV: Exploiting Key-Value Stores for Event Log Processing  

E-print Network

Wang1 X. Sean Wang3 1 HP Labs {zhao.cao, shimin.chen, min.wang6}@hp.com 2 School of Computing, University of Utah lifeifei@cs.utah.edu 3 School of Computer Science, Fudan University xywang management, IT trouble shoot- ing, to user behavior analysis. Recent years have seen a rapid growth in system

60

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

61

Downhole memory-logging tools  

SciTech Connect

Logging technologies developed 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: (i) there is a general lack of vetted, high-temperature instrumentation, and (ii) 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 on-board 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 on 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{degrees}C 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. 8 refs.

Lysne, P.

1992-01-01

62

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

63

Hermes Changes Log Daniel Fitton  

E-print Network

change to support the new Client Agent feature: · Run-length decoding of Note images sent by ClientHermes Changes Log Daniel Fitton November 1, 2004 This document chronicles the changes made software components is deployed the changes and date are noted. Figure 1 graphically shows the deployment

Cheverst, Keith

64

A Method to Dynamic Stochastic Multicriteria Decision Making with Log-Normally Distributed Random Variables  

PubMed Central

We investigate the dynamic stochastic multicriteria decision making (SMCDM) problems, in which the criterion values take the form of log-normally distributed random variables, and the argument information is collected from different periods. We propose two new geometric aggregation operators, such as the log-normal distribution weighted geometric (LNDWG) operator and the dynamic log-normal distribution weighted geometric (DLNDWG) operator, and develop a method for dynamic SMCDM with log-normally distributed random variables. This method uses the DLNDWG operator and the LNDWG operator to aggregate the log-normally distributed criterion values, utilizes the entropy model of Shannon to generate the time weight vector, and utilizes the expectation values and variances of log-normal distributions to rank the alternatives and select the best one. Finally, an example is given to illustrate the feasibility and effectiveness of this developed method. PMID:24223501

Wang, Jian-Qiang; Deng, Sheng-Yue

2013-01-01

65

Case history on geothermal-well-log interpretation: Surprise Valley, California  

SciTech Connect

Well logs from a 1972 geothermal well drilled in California's Surprise Valley are discussed. The well is in an igneous formation, primarily basalt in the logged interval, and had a bottom-hole temperature of about 170/sup 0/C at a total depth exceeding 1400 m. It produced good flow rates from what is presumably a formation with predominately fracture-related permeability. The well has special interest because fractures could be located approximately by the appearance of well-defined secondary crystallization in the drill cuttings. The original use of the log data in evaluating the well when it was drilled is discussed. In addition, the log data are reviewed and valuable data are obtained on log response in basalts, the effects of secondary mineralization, fracture detection, and aspects of the resistivity logs. The Surprise Valley well gives a clear demonstration of the value of thorough logging in geothermal exploratory wells, especially in the identification and location of potential production zones.

Rigby, F.A.; Zebal, G.P.

1981-06-01

66

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

67

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

68

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

69

Audit Log for Forensic Photography  

NASA Astrophysics Data System (ADS)

We propose an architecture for an audit log system for forensic photography, which ensures that the chain of evidence of a photograph taken by a photographer at a crime scene is maintained from the point of image capture to its end application at trial. The requirements for such a system are specified and the results of experiments are presented which demonstrate the feasibility of the proposed approach.

Neville, Timothy; Sorell, Matthew

70

Lithostratigraphy from downhole logs in Hole AND-1B, Antarctica  

USGS Publications Warehouse

The ANDRILL (Antarctic Drilling Project) McMurdo Ice Shelf (MIS) project drilled 1285 m of sediment in Hole AND1B, representing the past 12 m.y. of glacial history. Downhole geophysical logs were acquired to a depth of 1018 mbsf (meters below seafloor), and are complementary to data acquired from the core. The natural gamma radiation (NGR) and magnetic susceptibility logs are particularly useful for understanding lithological and paleoenvironmental change at ANDRILL McMurdo Ice Shelf Hole AND1B. NGR logs cover the entire interval from the seafloor to 1018 mbsf, and magnetic susceptibility and other logs covered the open hole intervals between 692 and 1018 and 237342 mbsf. In the upper part of AND1B, clear alternations between low and high NGR values distinguish between diatomite (lacking minerals containing naturally radioactive K, U, and Th) and diamictite (containing K-bearing clays, K-feldspar, mica, 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 diamictites (relatively high in magnetite). Sandstones can be distinguished by their high resistivity values in AND1B. On the basis of these three downhole logs, diamictite, claystones, and sandstones can be predicted correctly for 74% of the 6921018 mbsf interval. The logs were then used to predict facies for the 6% of this interval that was unrecovered by coring. 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 and the transitions from subice diamictite to open-water diatomite.

Williams, Trevor; Morin, Roger H.; Jarrard, Richard D.; Jackolski, Chris L.; Henrys, Stuart A.; Niessen, Frank; Magens, Diana; Kuhn, Gerhard; Monien, Donata; Powell, Ross D.

2012-01-01

71

2010 Daily Fire Log Date & Time  

E-print Network

and transported to Campbell Co. jail. Fire/Smoke/Sprinkler Alarm Log December 2010 Report #: 2010-00571 Reported responded and cleared the scene; subject transported to Campbell County jail. #12;2010 Daily Fire Log CAD

Boyce, Richard L.

72

29 CFR 788.9 - Preparing * * * logs.  

Code of Federal Regulations, 2011 CFR

...AND HOUR DIVISION, DEPARTMENT OF LABOR STATEMENTS OF GENERAL POLICY OR INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS FORESTRY OR LOGGING OPERATIONS IN WHICH NOT MORE THAN EIGHT EMPLOYEES ARE EMPLOYED 788.9 Preparing * * * logs....

2011-07-01

73

29 CFR 788.9 - Preparing * * * logs.  

Code of Federal Regulations, 2010 CFR

...AND HOUR DIVISION, DEPARTMENT OF LABOR STATEMENTS OF GENERAL POLICY OR INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS FORESTRY OR LOGGING OPERATIONS IN WHICH NOT MORE THAN EIGHT EMPLOYEES ARE EMPLOYED 788.9 Preparing * * * logs....

2010-07-01

74

Technology & Science Web MSNBC Cosmic Log  

E-print Network

Home » Technology & Science » Science Web MSNBC Cosmic Log ABOUT COSMIC LOG Quantum fluctuations batteries. KN400, for example, could provide the energy for deep-sea sensors that monitor turtle migration

Lovley, Derek

75

29 CFR 1918.88 - Log operations.  

Code of Federal Regulations, 2010 CFR

...furnished and hung overside to the water's edge. (e) Jacob's ladder...employee is working logs out of the water, walking sticks 11 (safety sticks...loading of logs onto vessels from the water. (1) They shall be planked...

2010-07-01

76

29 CFR 1918.88 - Log operations.  

Code of Federal Regulations, 2012 CFR

...furnished and hung overside to the water's edge. (e) Jacob's ladder...employee is working logs out of the water, walking sticks 11 (safety sticks...loading of logs onto vessels from the water. (1) They shall be planked...

2012-07-01

77

29 CFR 1918.88 - Log operations.  

Code of Federal Regulations, 2011 CFR

...furnished and hung overside to the water's edge. (e) Jacob's ladder...employee is working logs out of the water, walking sticks 11 (safety sticks...loading of logs onto vessels from the water. (1) They shall be planked...

2011-07-01

78

Geophysical logging for mineral and engineering applications  

SciTech Connect

The book contains nonpetroleum logging methods and the more exotic techniques. Contents: History; Formation types; Borehole effects and mud; Electric logging systems; Radioactivity methods; Magnetic methods; Mechanical methods and sampling methods; Analog and digital systems; Interpretation methods.

Hallenburg, J.K.

1983-01-01

79

29 CFR 788.9 - Preparing * * * logs.  

...AND HOUR DIVISION, DEPARTMENT OF LABOR STATEMENTS OF GENERAL POLICY OR INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS FORESTRY OR LOGGING OPERATIONS IN WHICH NOT MORE THAN EIGHT EMPLOYEES ARE EMPLOYED 788.9 Preparing * * * logs....

2014-07-01

80

29 CFR 788.9 - Preparing * * * logs.  

Code of Federal Regulations, 2013 CFR

...AND HOUR DIVISION, DEPARTMENT OF LABOR STATEMENTS OF GENERAL POLICY OR INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS FORESTRY OR LOGGING OPERATIONS IN WHICH NOT MORE THAN EIGHT EMPLOYEES ARE EMPLOYED 788.9 Preparing * * * logs....

2013-07-01

81

Learning from Logged Implicit Exploration Data Alexander L. Strehl  

E-print Network

Learning from Logged Implicit Exploration Data Alexander L. Strehl Facebook Inc. 1601 S California Ave Palo Alto, CA 94304 astrehl@facebook.com John Langford Yahoo! Research 111 West 40th Street, 9th where only the value of a chosen action is learned. The primary challenge in a variety of settings

Kakade, Sham M.

82

Artifactual log-periodicity in finite size data: Relevance for earthquake aftershocks  

Microsoft Academic Search

The recently proposed discrete scale invariance and its associated log-periodicity are an elaboration of the concept of scale invariance in which the system is scale invariant only under powers of specific values of the magnification factor. We report on the discovery of a novel mechanism for such log-periodicity relying solely on the manipulation of data. This ``synthetic'' scenario for log-periodicity

Y. Huang; A. Johansen; M. W. Lee; H. Saleur; D. Sornette

2000-01-01

83

The Methodology of Search Log Analysis  

E-print Network

99 Chapter VI The Methodology of Search Log Analysis Bernard J. Jansen Pennsylvania State of and foundation for conducting Web search transaction log analysis. A search log analysis methodology is outlined consisting of three stages (i.e., collection, preparation, and analysis). The three stages of the methodology

Jansen, James

84

CORRUPTION AND ILLEGAL LOGGING IN THE WOOD  

E-print Network

deforestation Davide Pettenella University of Padova Agricultural University of Tirana Faculty of Forestry in deforestation and trade of illegal logging? 3. Which are the most affected countries? 4. Why do we need logging (World Bank Review of Global Forest Policy ­ 1999) Illegal logging have external effects

Pettenella, Davide

85

Using Well Logs in the Petroleum Industry  

NSDL National Science Digital Library

This exercise shows how well logs are used in the petroleum industry. It is designed as a first exposure to well logs for undergraduate geology majors and introduces not only well logs and their interpretation as proxies for stratigraphic sections, but also investigates concepts of porosity and permeability, oil reservoirs, and structural traps.

Borowski, Walter

86

Balloon logging with the inverted skyline  

NASA Technical Reports Server (NTRS)

There is a gap in aerial logging techniques that has to be filled. The need for a simple, safe, sizeable system has to be developed before aerial logging will become effective and accepted in the logging industry. This paper presents such a system designed on simple principles with realistic cost and ecological benefits.

Mosher, C. F.

1975-01-01

87

Data Mining of Network Logs  

NASA Technical Reports Server (NTRS)

The statement of purpose is to analyze network monitoring logs to support the computer incident response team. Specifically, gain a clear understanding of the Uniform Resource Locator (URL) and its structure, and provide a way to breakdown a URL based on protocol, host name domain name, path, and other attributes. Finally, provide a method to perform data reduction by identifying the different types of advertisements shown on a webpage for incident data analysis. The procedures used for analysis and data reduction will be a computer program which would analyze the URL and identify and advertisement links from the actual content links.

Collazo, Carlimar

2011-01-01

88

Internet Data logging and Display  

E-print Network

-OF-THE-ART Remotely located data loggers have been used extensively for collecting measurement data [2] [3] [4] [5] [6]. Convenient retrieval of the data from the data logging device has al- ways presented a problem [7] [8]. One solution, for ex- ample, takes... of the sample, (5) 64-bit 1-Wire ID of the sensor or device used to communicate with the sensor (this is stored as an array of 8 bytes, as well as the string representation of the ID), (6) description of the sen- sor, and (7) channel number (if the device has...

Sweeney, J., Jr.; Culp, C.; Haberl, J. S.

2001-01-01

89

O' Surgery Case Log Data, Where Art Thou?  

PubMed Central

Background The American College of Surgeons Case Log (ACS Case Log) represents a data system that satisfies the American Board of Surgery (ABS) Maintenance of Certification (MOC) program, yet has broad data fields for surgical subspecialties. Using the ACS Case Log, we have developed a method of data capture, categorization, and reporting of acute care surgery fellows' experiences. Study Design In July 2010, our Acute Care Surgery fellowship required our fellows to log their clinical experiences into the ACS Case Log. Cases were entered similar to billable documentation rules. Keywords were entered that specified institutional services and/or resuscitation types. This data was exported in comma separated value format, de-identified, and structured by Current Procedural Terminology (CPT) codes relevant to acute care surgery and sub-stratified by fellow and/or fellow year. Results Fifteen report types were created consisting of operative experience by service, procedure by major category (cardiothoracic, vascular, solid organ, abdominal wall, hollow viscus, and soft tissue), total resuscitations, ultrasound, airway, Intensive Care Unit services, basic neurosurgery, and basic orthopaedics. Results are viewable via a secure web application, accessible nationally, and exportable to many formats. Conclusions Utilizing the ACS Case Log satisfies the ABS MOC program requirements and provides a method for monitoring and reporting acute care surgery fellow experiences. This system is flexible to accommodate the needs of surgical subspecialties and their training programs. As documentation requirements expand, efficient clinical documentation is a must for the busy surgeon. Although, our data entry and processing method has the immediate capacity for acute care surgery fellowships nationwide, multiple larger decisions regarding national case log systems should be encouraged. PMID:22634118

Patel, Mayur B; Guillamondegui, Oscar D; Ott, Mickey M; Palmiter, Kimberly A; May, Addison K

2012-01-01

90

Use of thermal resistivity logs in stratigraphic correlation. [Correlation of temperature gradient with depth  

Microsoft Academic Search

Since it has been found that the heat flow along a borehole rarely deviates more than 20 percent from the mean equilibrium value and that formation thermal resistivities may vary by as much as an order of magnitude, the profile of temperature gradient versus depth is equivalent to a log of thermal resistivity (T-log). In this work high precision temperature

Beck

1977-01-01

91

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

92

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

93

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. 18 figs.

Gannon, J.C.; Payne, J.J.

1996-09-03

94

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

2013-05-01

95

Selective logging and its relation to deforestation  

NASA Astrophysics Data System (ADS)

Selective logging is a major contributor to the social, economic, and ecological dynamics of Brazilian Amazonia. Logging activities have expanded from low-volume floodplain harvests in past centuries to high-volume operations today that take about 25 million m3 of wood from the forest each year. The most common highimpact conventional and often illegal logging practices result in major collateral forest damage, with cascading effects on ecosystem processes. Initial carbon losses and forest recovery rates following timber harvest are tightly linked to initial logging intensity, which drives changes in forest gap fraction, fragmentation, and the light environment. Other ecological processes affected by selective logging include nutrient cycling, hydrological function, and postharvest disturbance such as fire. This chapter synthesizes the ecological impacts of selective logging, in the context of the recent socioeconomic conditions throughout Brazilian Amazonia, as determined from field-based and remote sensing studies carried out during the Large-Scale Biosphere-Atmosphere Experiment in Amazonia program.

Asner, Gregory P.; Keller, Michael; Lentini, Marco; Merry, Frank; Souza, Carlos, Jr.

96

Toxic species evolution from guayule fireplace logs  

E-print Network

or cellulose fiberboard. As expected, the amount of smoke produced by burning a guayule fireplace log under test conditions was far less than the smoke produced by burning a synthetic plastic material such as polyvinyl chloride. It should be noted... Smoke Test Data for Selected Materials ' MATERIALS PERCENT SMOKE+ BASED ON INITIAL MASS MASS LOSS Southern Yellow Pine Red Oah Medium Density Hardborad Guayuie Fireplace Log Cotton Gin Trash Fireplace Log Cellulose Fiberboard Polyvinyl...

Soderman, Kristi Lee

2012-06-07

97

Characterization of geological formations by physical parameters obtained through full waveform acoustic logging  

NASA Astrophysics Data System (ADS)

In this paper, we will show through a field example that full wave form acoustic logging allows a quantitative evaluation of geological formations. For that purpose, conventional logs and their associated standard deviation (Std) must be computed (formation velocities, amplitudes, frequencies, etc.) since the Std is used to estimate the uncertainties associated with the log and to edit other logs. The missing values are then reconstructed by geostatistical interpolation (ordinary kriging and co-kriging). The shear velocity and density of the formation are also estimated in order to obtain mechanical parameters such as Poissons ratio or shear modulus. Since the converted refracted shear waves can be recorded in fast formations, a joint method based on the local measurement of the shear velocity by picking the arrival times of the refracted S wave and interpolation by co-kriging with P-wave velocity log has been used to compute a continuous shear velocity log. The Analysis of the dispersive properties of the Stoneley modes has then been used to estimate density variations and build iteratively a density log from an a priori density model. Furthermore, we will show that a dimensionless shape index can be used as a qualitative acoustic attribute to detect the presence of interfering waves, anomalic zones and to obtain a measurement of the attenuation. We will also show that P-wave attenuation , P-wave frequency and acoustic porosity logs can be fruitfully used to compute an acoustic permeability log.

Mari, J. L.; Gaudiani, P.; Delay, J.

98

An outline of the log minimal model program for the moduli space of curves  

E-print Network

Hassett and Keel predicted that there is a descending sequence of critical $\\alpha$ values where the log canonical model for the moduli space of stable curves with respect to $\\alpha \\delta$ changes. We derive a conjectural formula for the critical values in two different ways, by working out the intersection theory of the moduli space of hyperelliptic curves and by computing the GIT stability of certain curves with tails and bridges. The results give a rough outline of how the log minimal model program would proceed, telling us when the log canonical model changes and which curves are to be discarded and acquired at the critical steps.

Hyeon, Donghoon

2010-01-01

99

Method for making logging sleeve  

SciTech Connect

A method is described for making a logging sleeve adapted to slide on and off a drill string in a well for measuring a downhole characteristic in the well. The method includes the steps of: (a) placing at least one layer of resin-coated fibers in a longitudinal groove in a mandrel; (b) placing an elongated electrical conductor having an end on the resin-coated fibers in the groove; (c) placing additional resin-coated fibers on the conductor to substantially fill the groove; (d) wrapping resin-coated fibers around the mandrel to cover the fibers in the groove; (e) mounting an electrically conductive annular ring with a longitudinally extending anchor strip on the resin-coated fibers wrapped around the mandrel; (f) electrically connecting the end of the conductor to the ring; (g) wrapping additional resin-coated fibers around the mandrel and at least a portion of the strip; (h) curing the resin to form the sleeve with an inner and longitudinal spline adapted to make a sliding fit in a matching longitudinal groove in the drill string; and (i) sliding the sleeve off the mandrel.

More, H.S.; Koch, C.E.

1986-07-22

100

Site attenuation with log-periodic antennas  

Microsoft Academic Search

Site attenuation measurements made with biconical antennas below 200 MHz are found to agree rather well with calculations based on point dipole antennas. The log-periodic dipole antennas used above 200 MHz differ more drastically than the biconical from an ideal point dipole. Discrepancies arising from the use of log-periodic antennas are examined, and a simple modification of the site attenuation

J. D. Gavenda

1993-01-01

101

Microstrip log periodic antenna using circuit simulator  

Microsoft Academic Search

This paper described the method of designing the quasi log periodically scaled microstrip antenna using S parameter of the antenna and microstrip transmission line circuit. The novelty of this antenna structure is a combination of a small number of elements to create a log periodic array with modest bandwidth. The radiating element is a square patch antenna. The input impedance

M. K. A. Rahim; P. Gardner

2003-01-01

102

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

103

Injection Well Logging Using Viscous EOR Fluids  

Microsoft Academic Search

A new tool has been developed that overcomes problems associated with logging injection wells in the presence of viscous fluids. The tool was evaluated in the laboratory and the field in water and polymer injection wells. Results indicate that the tool provides better information than conventional equipment. Special attention to log interpretation is required in zones where the flow pattern

Bruce Knight; Mohammad Davarzani

1986-01-01

104

Cracking the Code: Web Log Analysis.  

ERIC Educational Resources Information Center

Demonstrates the benefits and problems of using Web log analysis to extract information about the global information customer. The Web logs examined were those of "The Times" and "Sunday Times." Highlights include the measures and metrics; the data and its meaning; and analyses with potential (AEF)

Nicholas, David; Huntington, Paul; Lievesley, Nat; Withey, Richard

1999-01-01

105

Chernoff's density is log-concave  

PubMed Central

We show that the density of Z = argmax{W (t) ? t2}, sometimes known as Chernoffs density, is log-concave. We conjecture that Chernoffs density is strongly log-concave or super-Gaussian, and provide evidence in support of the conjecture. PMID:24761134

BALABDAOUI, FADOUA; WELLNER, JON A.

2014-01-01

106

Log-binomial models: exploring failed convergence  

PubMed Central

Background Relative risk is a summary metric that is commonly used in epidemiological investigations. Increasingly, epidemiologists are using log-binomial models to study the impact of a set of predictor variables on a single binary outcome, as they naturally offer relative risks. However, standard statistical software may report failed convergence when attempting to fit log-binomial models in certain settings. The methods that have been proposed in the literature for dealing with failed convergence use approximate solutions to avoid the issue. This research looks directly at the log-likelihood function for the simplest log-binomial model where failed convergence has been observed, a model with a single linear predictor with three levels. The possible causes of failed convergence are explored and potential solutions are presented for some cases. Results Among the principal causes is a failure of the fitting algorithm to converge despite the log-likelihood function having a single finite maximum. Despite these limitations, log-binomial models are a viable option for epidemiologists wishing to describe the relationship between a set of predictors and a binary outcome where relative risk is the desired summary measure. Conclusions Epidemiologists are encouraged to continue to use log-binomial models and advocate for improvements to the fitting algorithms to promote the widespread use of log-binomial models. PMID:24330636

2013-01-01

107

Security Event and Log Management Service  

E-print Network

Services - The Smarter Decision 6 Introducing IBM Internet Security Systems Security Event and Log (SOC) Event Monitoring Service 13 Conclusion 14 Protection on demand 14 Contact IBM Internet Security Systems to Learn More 14 About IBM Internet Security Systems Contents Security Event and Log Management

108

Using Satellite Imagery to Detect Illegal Logging  

E-print Network

.globalforestwatch.org/english/about/illeglog/illeglog_workshop_presentations.htm #12;GFW Remote Sensing Work on Illegal Logging · Cameroon ­ pilot dataset completed · Central Africa · Applications outside Central Africa · Make Landsat Imagery freely available · Provide new datasets (logging

109

The velocity-deviation log: A tool to predict pore type and permeability trends in carbonate drill holes from sonic and porosity or density logs  

SciTech Connect

The velocity-deviation log, which is calculated by combining the sonic log with the neutron-porosity or density log, provides a tool to obtain downhole information on the predominant pore type in carbonates. The log can be used to trace the downhole distribution of diagenetic processes and to estimate trends in permeability. Laboratory measurements on over 300 discrete carbonate samples reveal that sonic velocity is a function not only of total porosity, but also of the predominant pore type. In general, there is an inverse porosity-velocity correlation, but significant deviations occur from this relationship for certain pore types. Frame-forming pore types, such as moldic or intrafossil porosity, result in significantly higher velocity values at equal total porosities than do pore types that are not embedded in a rigid rock frame, such as interparticle porosity or microporosity. The results of the laboratory measurements can be applied to expand interpretations of standard wireline-log data, as shown in this study on two drill holes through Neogene carbonates from the Great Bahama Bank. The velocity-deviation log is calculated by first converting porosity-log data to a synthetic velocity log using a time-average equation. The difference between the real sonic log and the synthetic sonic log can then be plotted as a velocity-deviation log. Because deviations are the result of the variability of velocity at a certain porosity, the deviation log reflects the different rock-physical signatures of the different pore types. Positive velocity deviations mark zones where velocity is higher than expected from the porosity values, such as zones where frame-forming pore types dominate. Zero deviations show intervals where the rock lacks a rigid frame, such as in carbonates with high interparticle porosity or microporosity. Negative deviations mark zones in which sonic log velocities are unusually low, caused, for instance, by a cavernous bore-hole wall, fracturing, or possibly by a high content of free gas. By tracing the velocity deviations continuously downhole, one can identify diagenetic zones that are characterized by these different pore types. In addition, this method can be used to observe permeability trends because pore types influence the permeability of the rock.

Anselmetti, F.S.; Eberli, G.P. [Univ. of Miami, FL (United States). Comparative Sedimentology Lab.

1999-03-01

110

Shippers in Indonesia fight decree on illegal logging Shippers in Indonesia fight decree on illegal logging  

E-print Network

Shippers in Indonesia fight decree on illegal logging Shippers in Indonesia fight decree on illegal Organization (ITTO), shippers in Indonesia are threatening to stop transporting logs if the government insists harvesting affects 700,000-850,000 hectares of forest per year in Indonesia, but widespread illegal logging

111

An integrated digital well logging system  

SciTech Connect

Basics of the SLAM Digital Combination Logging System are discussed including an overview which describes each of its major components; the computerbased surface data acquisition system, wellsite analysis software package, and the individual and combination measurement systems used with SLAM. Combination logging runs that are possible with the SLAM system are presented to illustrate their application in a number of different geologic and borehole conditions. The advantages to performing combination logging runs are also discussed. Log presentations available are illustrated to demonstrate methods for displaying combination log data in usable formats. Diagnostic programs and troubleshooting aids are reviewed to demonstrate their ability to help predict when equipment is becoming marginal, and to minimize lost time due to equipment failure. Standard methods for performing instrument calibrations are described, including techniques to perform master calibrations at the shop or wellsite, as well as before and after wellsite checks performed with instruments suspended over the borehole, or on the catwalk.

Peressini, B.; Fertl, W.H.; Howells, A.P.S.

1982-09-01

112

Valuing Essays: Essaying Values  

ERIC Educational Resources Information Center

The essay regularly comes under attack. It is criticised for being rigidly linear rather than flexible and reflective. I first challenge this view by examining reasons why the essay should be valued as an important genre. Secondly, I propose that in using the essay form students and academics necessarily exemplify their own critical values. Essays

Badley, Graham

2010-01-01

113

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

114

Log-periodic optical antennas with broadband directivity  

NASA Astrophysics Data System (ADS)

Optical antennas offer unique possibilities for light manipulation on a sub-wavelength scale. Here, we study log-periodic antennas that exhibit broadband directivity as a result of the self-similar relation between the lengths, separations and widths of the elements. We show through numerical simulations that the log-periodic designs have a considerable potential for improvement of both directivity and operation bandwidth over classical Yagi-Uda designs. Moreover, the directivity is more robust against changes in the location of the source or detector at different antenna elements. We systematically study the influence of geometrical parameters on angular performance and local field enhancement to arrive at optimum values. Next, we demonstrate that introducing a gap in the dipole array architecture can provide at least a ten-fold enhancement of the emitted power. Finally we present an optical zigzag antenna capable of both broader spectral response and even higher directivity.

Pavlov, Radostin S.; Curto, Alberto G.; van Hulst, Niek F.

2012-07-01

115

A modification of the fusion model for log polar coordinates  

NASA Technical Reports Server (NTRS)

The fusion mechanism for application in stereo analysis of range restricted the depth of field and therefore required a shift variant mechanism in the peripheral area to find disparity. Misregistration was prevented by restricting the disparity detection range to a neighborhood spanned by the directional edge detection filters. This transformation was essentially accomplished by a nonuniform resampling of the original image in a horizontal direction. While this is easily implemented for digital processing, the approach does not (in the peripheral vision area) model the log-conformal mapping which is known to occur in the human mechanism. This paper therefore modifies the original fusion concept in the peripheral area to include the polar exponential grid-to-log conformal tesselation. Examples of the fusion process resulting in accurate disparity values are given.

Griswold, N. C.; Weiman, Carl F. R.

1990-01-01

116

2010 Daily Log Report #: 2010-00262  

E-print Network

of Marijuana Report #: 2010-00256 Reported: 06/17/10 0851 Occurred: Same Incident: Traffic Crash Location: Lot;2010 Daily Log Report #: 2010-00249 Reported: 06/03/10 1702 Occurred: Same Incident: Medical Emergency

Boyce, Richard L.

117

Daily Crime Log Wednesday, June 25, 2014  

E-print Network

Daily Crime Log Wednesday, June 25, 2014 8:53:25 AM Calendar Year: 2014 Date/Time Reported Offense) CO A 17-year-old juvenile was issued a Carbondale City notice to appear and released. (140619001) LOT

118

Dewarless Logging Tool - 1st Generation.  

National Technical Information Service (NTIS)

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...

Henfling Normann

2000-01-01

119

Business Plan SYMAS Custom Log Fencing LTD.  

E-print Network

..........................................................,....32 #12;1 Executive Summary SYMAS is a fencing products company, specializing in custom rustic log with express written consent. #12;Table of Contents Executive Summary.......................................................................19 5.0 Operations...............................................................21 5.1 Scope

120

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

121

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

122

Recover it yourself with user logging  

SciTech Connect

IMAGE logging is a good product that has proved to be an effective and accurate way to save interactive transactions for recovery and audit purposes. There is one shortcoming with the product in that it only logs transactions within the IMAGE domain. Some applications require that KSAM and MPE files be updated in an on-line system. How can these files be recovered. One answer is to use a recoverable program structure that not only posts the interactive transactions, but recovers them as well. The user logging facility is used to store the successful transactions to either tape or disc. This paper will discuss the recoverable program structure and the user logging subsystem.

Weir, D.

1984-01-01

123

LogCauchy, log-sech and lognormal distributions of species abundances in forest communities  

USGS Publications Warehouse

Species-abundance (SA) pattern is one of the most fundamental aspects of biological community structure, providing important information regarding species richness, species-area relation and succession. To better describe the SA distribution (SAD) in a community, based on the widely used lognormal (LN) distribution model with exp(-x2) roll-off on Preston's octave scale, this study proposed two additional models, logCauchy (LC) and log-sech (LS), respectively with roll-offs of simple x-2 and e-x. The estimation of the theoretical total number of species in the whole community, S*, including very rare species not yet collected in sample, was derived from the left-truncation of each distribution. We fitted these three models by Levenberg-Marquardt nonlinear regression and measured the model fit to the data using coefficient of determination of regression, parameters' t-test and distribution's Kolmogorov-Smirnov (KS) test. Examining the SA data from six forest communities (five in lower subtropics and one in tropics), we found that: (1) on a log scale, all three models that are bell-shaped and left-truncated statistically adequately fitted the observed SADs, and the LC and LS did better than the LN; (2) from each model and for each community the S* values estimated by the integral and summation methods were almost equal, allowing us to estimate S* using a simple integral formula and to estimate its asymptotic confidence internals by regression of a transformed model containing it; (3) following the order of LC, LS, and LN, the fitted distributions became lower in the peak, less concave in the side, and shorter in the tail, and overall the LC tended to overestimate, the LN tended to underestimate, while the LS was intermediate but slightly tended to underestimate, the observed SADs (particularly the number of common species in the right tail); (4) the six communities had some similar structural properties such as following similar distribution models, having a common modal octave and a similar proportion of common species. We suggested that what follows the LN distribution should follow (or better follow) the LC and LS, and that the LC, LS and LN distributions represent a "sequential distribution set" in which one can find a best fit to the observed SAD. ?? 2004 Elsevier B.V. All rights reserved.

Yin, Z. -Y.; Peng, S. -L.; Ren, H.; Guo, Q.; Chen, Z. -H.

2005-01-01

124

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

125

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

126

Log-periodic route to fractal functions  

Microsoft Academic Search

Log-periodic oscillations have been found to decorate the usual power-law behavior found to describe the approach to a critical point, when the continuous scale-invariance symmetry is partially broken into a discrete-scale invariance symmetry. For Ising or Potts spins with ferromagnetic interactions on hierarchical systems, the relative magnitude of the log-periodic corrections are usually very small, of order 10-5. In growth

S. Gluzman; D. Sornette

2002-01-01

127

Utilization of Electrical Impedance Tomography to Detect Internal Anomalies in Southern Pine Logs  

NASA Astrophysics Data System (ADS)

A large body of research has shown that knowledge of internal defect location in logs prior to sawing has the potential to significantly increase lumber value yield. This paper describes a relatively low-capital log scanning technique based on Electrical Impedance Tomography (EIT) to image anomalies interior to sawlogs. Static testing results showed that knots, juvenile and compression wood internal to logs can be detected. Although resolution is lower than that of CT and NMR technologies, the low cost of this EIT application should render it competitive.

Steele, Philip; Cooper, Jerome

2006-03-01

128

47 CFR 73.782 - Retention of logs.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 false Retention of logs. 73.782 Section 73.782 Telecommunication FEDERAL COMMUNICATIONS COMMISSION...SERVICES International Broadcast Stations 73.782 Retention of logs. Logs of international...

2010-10-01

129

Flowing fluid electric conductivity logging for a deep artesian well in fractured rock with regional flow  

NASA Astrophysics Data System (ADS)

SummaryThe flowing fluid electric conductivity (FFEC) logging method is a well-logging technique that may be used to estimate flow rate, salinity, transmissivity, and hydraulic head of individual fractures or high-permeability zones intersected by a wellbore. Wellbore fluid is first replaced with fluid of a contrasting electric conductivity, then repeated FEC logging is done while the well is pumped. Zones where fluid flows into the wellbore show peaks in the FEC logs, which may be analyzed to infer inflow rate and salinity of the individual fractures. Conducting the procedure with two or more pumping rates (multi-rate FFEC logging) enables individual fracture transmissivity and hydraulic head to be determined. Here we describe the first application of the multi-rate FFEC logging method to an artesian well, using a 500-m well in fractured rock at Horonobe, Japan. An additional new factor at the site is the presence of regional groundwater flow, which heretofore has only been studied with synthetic data. FFEC logging was conducted for two different pumping rates. Several analysis techniques had to be adapted to account for the artesian nature of the well. The results were subsequently compared with independent salinity measurements and transmissivity and hydraulic head values obtained from packer tests in the same well. Despite non-ideal operating conditions, multi-rate FFEC logging successfully determined flow rate, salinity, and transmissivity of 17 conducting fractures intercepted by the logged section of the borehole, including two fractures with regional groundwater flow. Predictions of hydraulic head were less accurate, a not unexpected result in light of operational problems and the form of the equation for hydraulic head, which involves the difference between two uncertain quantities. This study illustrates the strengths and weaknesses of the multi-rate FFEC logging method applied to artesian wells. In conjunction with previous studies, it demonstrates the usefulness of the method for a broad range of conditions encountered in subsurface fractured rock.

Doughty, Christine; Tsang, Chin-Fu; Yabuuchi, Satoshi; Kunimaru, Takanori

2013-03-01

130

Arabidopsis lonely guy (LOG) multiple mutants reveal a central role of the LOG-dependent pathway in cytokinin activation.  

PubMed

Cytokinins are phytohormones that play key roles in the maintenance of stem cell activity in plants. Although alternative single-step and two-step activation pathways for cytokinin have been proposed, the significance of the single-step pathway which is catalyzed by LONELY GUY (LOG), is not fully understood. We analyzed the metabolic flow of cytokinin activation in Arabidopsis log multiple mutants using stable isotope-labeled tracers and characterized the mutants' morphological and developmental phenotypes. In tracer experiments, cytokinin activation was inhibited most pronouncedly by log7, while the other log mutations had cumulative effects. Although sextuple or lower-order mutants did not show drastic phenotypes in vegetative growth, the log1log2log3log4log5log7log8 septuple T-DNA insertion mutant in which the LOG-dependent pathway is impaired, displayed severe retardation of shoot and root growth with defects in the maintenance of the apical meristems. Detailed observation of the mutants showed that LOG7 was required for the maintenance of shoot apical meristem size. LOG7 was also suggested to play a role for normal primary root growth together with LOG3 and LOG4. These results suggest a dominant role of the single-step activation pathway mediated by LOGs for cytokinin production, and overlapping but differentiated functions of the members of the LOG gene family in growth and development. PMID:22059596

Tokunaga, Hiroki; Kojima, Mikiko; Kuroha, Takeshi; Ishida, Takashi; Sugimoto, Keiko; Kiba, Takatoshi; Sakakibara, Hitoshi

2012-01-01

131

Log-Linear Analysis for an AxBxC Contingency Table  

NSDL National Science Digital Library

Richard Lowry of Vassar College has created a log-linear analysis which is a version of chi-square analysis. The relevant values are calculated by way of weighted natural logarithms. This page will calculate several values of G^2. This is a nice interactive resource which allows the user to manipulate the data to better understand the statistical methods.

Lowry, Richard

2009-01-14

132

An outline of the log minimal model program for the moduli space of curves  

Microsoft Academic Search

Hassett and Keel predicted that there is a descending sequence of critical $\\\\alpha$ values where the log canonical model for the moduli space of stable curves with respect to $\\\\alpha \\\\delta$ changes. We derive a conjectural formula for the critical values in two different ways, by working out the intersection theory of the moduli space of hyperelliptic curves and by

Donghoon Hyeon

2010-01-01

133

In vitro propagation of pecan, Carya illinoinensis (Wang) K. Koc  

E-print Network

the most rooting in Prunus ~s and ~C donia under the conditions he investigated. McCown and Amos (48) and Lloyd and McCown (44) d ! p d ' ill i hl y y B I* ~ih ll var. azechuanica and Kalmia latifolia respectively using continuous illumination in both... the most rooting in Prunus ~s and ~C donia under the conditions he investigated. McCown and Amos (48) and Lloyd and McCown (44) d ! p d ' ill i hl y y B I* ~ih ll var. azechuanica and Kalmia latifolia respectively using continuous illumination in both...

Hansen, Keith Christian

2012-06-07

134

Classial Ciphers: Affine Block Ciphers Cetin Kaya Koc  

E-print Network

/Output Alphabet and Encoding Input/output alphabet is {a, b, . . . , z} with encoding {0, 1, . . . , 25} However, other encodings can also be used, for example, we can increase the input size by adding capital letters of these vectors and matrices are from Zm and the arithmetic is performed in the ring (Zm, +, �), i.e., modulo m

135

Unconventional neutron sources for oil well logging  

NASA Astrophysics Data System (ADS)

Americium-Beryllium (AmBe) radiological neutron sources have been widely used in the petroleum industry for well logging purposes. There is strong desire on the part of various governmental and regulatory bodies to find alternate sources due to the high activity and small size of AmBe sources. Other neutron sources are available, both radiological (252Cf) and electronic accelerator driven (D-D and D-T). All of these, however, have substantially different neutron energy spectra from AmBe and thus cause significantly different responses in well logging tools. We report on simulations performed using unconventional sources and techniques to attempt to better replicate the porosity and carbon/oxygen ratio responses a well logging tool would see from AmBe neutrons. The AmBe response of these two types of tools is compared to the response from 252Cf, D-D, D-T, filtered D-T, and T-T sources.

Frankle, C. M.; Dale, G. E.

2013-09-01

136

Gel-log flocculants treat drainage  

SciTech Connect

Sedimentation ponds are often located at sites difficult to access and where electricity is not available. The problem of flocculant treatment to increase settling rates and of monitoring the system can be met by a new form of flocculant presentation in gel logs. Each log weighs 40 lbs and measures 18 in by 9 in diameter. It is wrapped in wire mesh and placed in the channel feeding the retention pond. The log gradually dissolves at a rate determined by its surface area, the water flow in contact with the gel and the water temperature. Some trial and error is necessary to achieve the correct dosage rate, but the method has been used satisfactorily for over a year.

Not Available

1982-09-01

137

A microwave printed planar log-periodic dipole array antenna  

NASA Astrophysics Data System (ADS)

A microwave printed planar log-periodic dipole array (LPDA) antenna analysis and design procedure is presented together with the description of a planar feeding technique. The effects of the dielectric substrate on the antenna design are also discussed and taken into account. A numerical technique using the finite element method is employed to obtain the characteristic impedance and effective dielectric constant of the transmission lines involved, i.e., an unbalanced stripline and a balanced line having only two parallel strips. A 4-8 GHz printed LPDA antenna was manufactured and tested, showing very good radiation pattern and voltage standing-wave ratio (VSWR) values over the entire frequency range.

Pantoja, R. R.; Sapienza, A. R.; Medeiros-Filho, F. C.

1987-10-01

138

Anisotropic anomalous diffusion modulated by log-periodic oscillations.  

PubMed

We introduce finite ramified self-affine substrates in two dimensions with a set of appropriate hopping rates between nearest-neighbor sites where the diffusion of a single random walk presents an anomalous anisotropic behavior modulated by log-periodic oscillations. The anisotropy is revealed by two different random-walk exponents ?(x) and ?(y) in the x and y directions, respectively. The values of these exponents as well as the periods of the oscillations are obtained analytically and confirmed by Monte Carlo simulations. PMID:23005367

Padilla, L; Mrtin, H O; Iguain, J L

2012-07-01

139

Anisotropic anomalous diffusion modulated by log-periodic oscillations  

NASA Astrophysics Data System (ADS)

We introduce finite ramified self-affine substrates in two dimensions with a set of appropriate hopping rates between nearest-neighbor sites where the diffusion of a single random walk presents an anomalous anisotropic behavior modulated by log-periodic oscillations. The anisotropy is revealed by two different random-walk exponents ?x and ?y in the x and y directions, respectively. The values of these exponents as well as the periods of the oscillations are obtained analytically and confirmed by Monte Carlo simulations.

Padilla, L.; Mrtin, H. O.; Iguain, J. L.

2012-07-01

140

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

141

Wavefunctios of log-periodic oscillators  

E-print Network

We use the Lewis and Riesenfeld invariant method [\\textit{J. Math. Phys.} \\textbf{10}, 1458 (1969)] and a unitary transformation to obtain the exact Schr\\"{o}dinger 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 $m=m_0t/t_0$ and $\\omega= \\omega_0t_0/t$, which exhibits an exact log-periodic oscillation, behaves as the harmonic oscillator with $m$ and $\\omega$ constant.

Bessa, V; 10.1063/1.3601739

2012-01-01

142

Wave functions of log-periodic oscillators  

NASA Astrophysics Data System (ADS)

We use the Lewis and Riesenfeld invariant method [J. Math. Phys. 10, 1458 (1969)], 10.1063/1.1664991 and a unitary transformation to obtain the exact Schrdinger 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 = m0t/t0 and ? = ?0t0/t, which exhibits an exact log-periodic oscillation, behaves as the harmonic oscillator with m and ? constant.

Bessa, V.; Guedes, I.

2011-06-01

143

MAIL LOG, program summary and specifications  

NASA Technical Reports Server (NTRS)

The summary and specifications to obtain the software package, MAIL LOG, developed for the Scout Project Automatic Data System, SPADS are provided. The MAIL LOG program has four modes of operation: (1) input - putting new records into the data base; (2) revise - changing or modifying existing records in the data base; (3) search - finding special records existing in the data base; and (4) archive - store or put away existing records in the data base. The output includes special printouts of records in the data base and results from the input and search modes.

Harris, D. K.

1979-01-01

144

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

145

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

146

1. GENERAL VIEW OF LOG POND AND BOOM FOR UNLOADING ...  

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

1. GENERAL VIEW OF LOG POND AND BOOM FOR UNLOADING CEDAR LOGS FROM TRUCKS AT LOG DUMP, ADJACENT TO MILL; TRUCKS FORMERLY USED TRIP STAKES, THOUGH FOR SAFER HANDLING OF LOGS WELDED STAKES ARE NOW REQUIRED; AS A RESULT LOADING IS NOW DONE WITH A CRANE - Lester Shingle Mill, 1602 North Eighteenth Street, Sweet Home, Linn County, OR

147

On exploring heterogeneities from well logs using the empirical mode decomposition  

NASA Astrophysics Data System (ADS)

In contrast with the traditional analysis approaches, the Empirical Mode Decomposition (EMD) allows to study nonlinear and nonstationary data. Here, this technique is used to perform a scale-based decomposition from Algerian well logs and to investigate heterogeneities of the layers crossed by the wells. First, the well log data are decomposed into intrinsic mode functions (IMFs). Then, the total depth interval is divided into lithological subintervals. For each subinterval, we compute the mean wavenumber (km) of each mode (m). It is shown that the EMD method behaves as an almost dyadic filter bank, and the heterogeneity of each lithological subinterval can be measured using a scaling parameter value computed as the slope of a linear regression of the plot km vs. m in the log-linear graph. It is worth noting that this parameter can be used to describe underground heterogeneities. Keywords: empirical mode decomposition (EMD), well logs, multi-scale.

Gaci, Said; Zaourar, Naima; Hachay, Olga

2014-05-01

148

Performance evaluation of active wireline heave compensation systems in marine well logging environments  

NASA Astrophysics Data System (ADS)

The basic functionality and performance of a new Schlumberger active wireline heave compensation system on the JOIDES Resolution was evaluated during the sea trial and a 3-year period of the IODP Phase II operations. A suite of software programs was developed to enable real-time monitoring of the dynamics of logging tools, and assess the efficiency of wireline heave compensation during downhole operations. The evaluation of the system effectiveness was performed under normal logging conditions as well as during stationary tests. Logging data were analyzed for their overall quality and repeatability, and to assess the reliability of high-resolution data such as formation microscanner (FMS) electrical images. This revealed that the system reduces 65-80 % of displacement or 88-98 % variance of downhole tool motion in stationary mode under heave conditions of 0.2-1.5 m and water depths of 300-4,500 m in open holes. Under similar water/heave conditions, the compensator system reduces tool displacement by 50-60 %, or 75-84 % variance in downhole tool motion during normal logging operations. Such compensation efficiency (CE) is comparable to previous compensation systems, but using advanced and upgradeable technologies, and provides 50-85 % heave motion and heave variance attenuation. Moreover, logging down/up at low speeds (300-600 m/h) reduces the system's CE values by 15-20 %, and logging down at higher speeds (1,000-1,200 m/h) eliminates CE values by 55-65 %. Considering the high quality of the logging data collected, it is concluded that the new system can provide an improved level of compensation over previous systems. Also, if practically feasible, future integration of downhole cable dynamics as an input feedback into the current system could further improve its compensation efficiency during logging operations.

Liu, Tanzhuo; Iturrino, Gerardo; Goldberg, David; Meissner, Eric; Swain, Kerry; Furman, Clayton; Fitzgerald, Peter; Frisbee, Nathan; Chlimoun, Joe; Van Hyfte, John; Beyer, Ron

2013-02-01

149

Annual Logging Symposium, June 19-23, 2010 CONSTRUCTION OF RELIABLE STATIC AND DYNAMIC MULTI-LAYER  

E-print Network

.A. Copyright 2010, held jointly by the Society of Petrophysicists and Well Log Analysts (SPWLA that produce gas with null water influx. This anomalous behavior is due to relatively low values of deep

Torres-Verdín, Carlos

150

Securing Shareable Life-logs Reza Rawassizadeh  

E-print Network

. Sensors are the core components of the life-logs and they are used to sense contextual information. For instance a user can share content, find new friends based on the shared content (common interests) and stay information with a social community might be harmful. Allen [13] described that using life

151

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

152

A planar log-periodic antenna  

Microsoft Academic Search

A planar log-periodic antenna structure that has radiation characteristics similar to those of a half-wave dipole has been found. The bandwidth can be as large as desired, and antennas can be easily fabricated by using printed circuit techniques. When fed with a suitable balun, VSWR's lower than 1.8:1 can be obtained over a wide-frequency band.

K. Keen

1974-01-01

153

Mutual coupling between log-periodic antennas  

Microsoft Academic Search

Numerical techniques are used for the analysis of mutual coupling in arrays of log-periodic dipole antennas. The analysis is formulated in terms of impedance and admittance matrices for the dipole and transmission line networks. Approximations are made to allow the solution for moderately sized arrays to be practical with the existing generation of computers. Antenna patterns for the array are

R. Kyle

1970-01-01

154

Stagger tuned microstrip log-periodic antenna  

Microsoft Academic Search

Log-periodic dipole antennas (LPDA) have been extensively used since 1960 when their properties were described by Isbell, whose work was followed by the detailed analysis of Carrel (1961). Progress in microwave integrated circuits in the last decade has created a demand for compact antennas, along with the requirement that the systems have a large bandwidth. The approach for broadband configuration

Rajesh Kakkar; Girish Kumar

1996-01-01

155

[Human development and log-periodic law].  

PubMed

We suggest applying the log-periodic law formerly used to describe various crisis phenomena, in biology (evolutionary leaps), inorganic systems (earthquakes), societies and economy (economic crisis, market crashes) to the various steps of human ontogeny. We find a statistically significant agreement between this model and the data. PMID:12187644

Cash, Roland; Chaline, Jean; Nottale, Laurent; Grou, Pierre

2002-05-01

156

An Effective System for Mining Web Log  

Microsoft Academic Search

The WWW provides a simple yet effective media for users to search, browse, and retrieve information in the Web. Web log mining is a promising tool to study user behaviors, which could further benefit web-site designers with better organization and services. Although there are many existing systems that can be used to analyze the traversal path of web-site visitors, their

Zhenglu Yang; Yitong Wang; Masaru Kitsuregawa

2006-01-01

157

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.

158

ABUNDANCE THEOREM FOR SEMI LOG CANONICAL THREEFOLDS  

E-print Network

. The abundance theorem for semi log canonical surfaces was proved in [12, Chapter 8, 12] by L.­Y. Fong, S. Keel abundance theorem for threefolds proved by S. Keel, K. Matsuki and J. McKernan (See [10]). According to them.1)) and we prove the finiteness of them for curves and surfaces. It plays an important role in our proof

159

29 CFR 1910.266 - Logging operations.  

Code of Federal Regulations, 2010 CFR

...protection, such as heavy-duty logging boots that are waterproof or water repellant, cover...of part 1910. (5) Environmental conditions. All work...the fall of a tree, heavy rain or snow, extreme...contact with poisonous plants or animals....

2010-07-01

160

Modelling tropical forests response to logging  

NASA Astrophysics Data System (ADS)

Tropical rainforests are among the most threatened ecosystems by large-scale fragmentation due to human activity such as heavy logging and agricultural clearance. Although, they provide crucial ecosystem goods and services, such as sequestering carbon from the atmosphere, protecting watersheds and conserving biodiversity. In several countries forest resource extraction has experienced a shift from clearcutting to selective logging to maintain a significant forest cover and understock of living biomass. However the knowledge on the short and long-term effects of removing selected species in tropical rainforest are scarce and need to be further investigated. One of the main effects of selective logging on forest dynamics seems to be the local disturbance which involve the invasion of open space by weed, vines and climbers at the expense of the late-successional state cenosis. We present a simple deterministic model that describes the dynamics of tropical rainforest subject to selective logging to understand how and why weeds displace native species. We argue that the selective removal of tallest tropical trees carries out gaps of light that allow weeds, vines and climbers to prevail on native species, inhibiting the possibility of recovery of the original vegetation. Our results show that different regime shifts may occur depending on the type of forest management adopted. This hypothesis is supported by a dataset of trees height and weed/vines cover that we collected from 9 plots located in Central and West Africa both in untouched and managed areas.

Cazzolla Gatti, Roberto; Di Paola, Arianna; Valentini, Riccardo; Paparella, Francesco

2013-04-01

161

Gentle Logging System Evaluation (PARTICIPANTS' QUESTIONNAIRE REPORT)  

E-print Network

Raymond O. Miller and William E. Cook 1 Abstract Five, new, cut-to-length harvesting systems wereGentle Logging System Evaluation (PARTICIPANTS' QUESTIONNAIRE REPORT) November 26, 2001 Raymond O. Miller William E. Cook Published by Michigan State University Upper Peninsula Tree Improvement Center

162

Activating Metacognition through Online Learning Log (OLL)  

ERIC Educational Resources Information Center

This study aims to investigate the activation process of metacognition of learners who systematically reflect on their learning using Online Learning Logs (OLL) which were designed to encourage them to think about learning. The study is qualitative and attempts to identify the metacognitive strategies of learners and their attitudes towards OLL.

Kurt, Mustafa

2007-01-01

163

MAIL LOG, program theory, volume 2  

NASA Technical Reports Server (NTRS)

Information relevant to the MAIL LOG program theory is documented. The L-files for mail correspondence, design information release/report, and the drawing/engineering order are given. In addition, sources for miscellaneous external routines and special support routines are documented along with a glossary of terms.

Harris, D. K.

1979-01-01

164

Indonesia to fight illegal logging Kurniawan Hari  

E-print Network

Indonesia to fight illegal logging Kurniawan Hari The government should set up a task force to deal another $8.1 billion. "Indonesia's economy will collapse if these evil practices are not stopped," Ermaya in the current fiscal year and was three times Indonesia's foreign debt budget. Commission members said the sand

165

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

166

Determining Earthquake Recurrence Intervals from Trench Logs  

NSDL National Science Digital Library

Trench logs of the San Andreas Fault at Pallett Creek, CA are the data base for a lab or homework assignment that teaches about relative dating, radiometric dating, fault recurrence intervals and the reasons for uncertainty in predicting geologic phenomena. Students are given a trench log that includes several fault strands and dated stratigraphic horizons. They estimate the times of faulting based on bracketing ages of faulted and unfaulted strata. They compile a table with the faulting events from the trench log and additional events recognized in nearby trenches, then calculate maximum, minimum and average earthquake recurrence intervals for the San Andreas Fault in this area. They conclude by making their own prediction for the timing of the next earthquake. While basically an exercise in determining relative ages of geologic horizons and events, this assignment includes radiometric dates, recurrence intervals, and an obvious societal significance that has been well received by students. With minor modifications, this exercise has been used successfully with elementary school students through university undergraduate geology majors. Less experienced students can work in groups, with each group determining the age of a single fault strand; combining the results from different groups and calculating recurrence intervals can then be done as a class activity. University students in an introductory geology course for non-majors can add their data from the trench log to an existing table with other faulting events already provided. The exercise can be made more challenging for advanced students by using logs from several different trenches, requiring students to design the table themselves, and giving students the uncertainties for the radiometric dates rather than simple ages for the strata. Most studentsâat all levelsâare initially frustrated by their inability to determine an exact date of faulting from the available data. They gain a new appreciation for the task of the geoscientist who attempts to relate geologic phenomena to the human, rather than geologic, time scale.

Cashman, Patricia

167

I. (1) (log(|g(x)|)) = g(x) g(x) , (log(logx)) = 1  

E-print Network

A (5/9) I. (1) (log(|g(x)|)) = g(x) g(x) , (log(logx)) = 1 logx(logx) = 1 xlogx (2) ( h(x) g(x) ) = g(x)h(x)-g(x)h(x) g(x)2 , g(x) = e-x + 1, h(x) = ex + 1 ( ex + 1 e-x + 1 ) = (e-x + 1)(ex + 1) - (e-x + 1)(ex + 1) (e-x + 1)2 = 2 + ex + e-x (e-x + 1)2 (3) (1) , (log( x + 1 + x + 2)) = 1 x + 1 + x

Ochiai, Tadashi

168

Log-Periodiska Dipolantenner i Enkla Arrayer (Log-Periodic Dipole Antennas in Simple Arrays).  

National Technical Information Service (NTIS)

The report gives a theoretical description of log-periodic dipole antennas (LPDA) including some practical examples. The possibility of designing an antenna structure which is independent of frequency has been investigated. There are various geometrical c...

A. C. Vogel

1991-01-01

169

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

170

Determination of polymer log D distributions by micellar and microemulsion electrokinetic chromatography.  

PubMed

The characterization of the hydrophobicity of polymer compounds in solution remains a challenging issue of importance, especially for biomedical or pharmaceutical applications. To our knowledge, there is no data of polymer hydrophobicity (log D) in the literature. In this work, for the first time, the log D distributions of cationic polymers were characterized using micellar or microemulsion electrokinetic chromatography at physiological pH. The log D distributions of the polymer samples were obtained from the electrophoretic/chromatographic retardation of the polymer derivatives in presence of neutral micelles (or neutral microemulsion), using small cationic molecules for calibration. Separating electrolytes were based on a TRISchloride buffer containing a neutral surfactant (polyoxyethyleneglycoldodecyl ether) for the formation of micelles (in water) or microemulsion (in water/n-pentanol mixture).The log D distributions obtained at pH 7.4 using this method were in good agreement with the chemical structures of cationic polypeptides: poly(lys, phe) 1:1 > poly(lys, tyr) 1:1 > poly(lys, trp) 4:1 > poly(lys, ser)3:1 > poly(l-lysine), where x:y represents the molar ratio of each amino acid in the copolymer. Weight average octanolwater log D values and the dispersion of the log D distribution were also defined and determined for each polymer sample. PMID:24209298

Jin, Xiaoyun; Leclercq, Laurent; Cottet, Herv

2013-11-29

171

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

172

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

173

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

174

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.

175

Wideband quasi-log-periodic microstrip antenna  

Microsoft Academic Search

The paper describes a new design method for a wideband array of log-periodically sealed microstrip resonator antennas. The radiating elements are series-fed by a simple coplanar microstrip network. This network consists of an open-circuited feed line with a branch line connected to each radiating element. Both a network and a radiating model for the complete structure are explained. These models

H. Pues; J. Bogaers; R. Pieck; A. van de Capelle

1981-01-01

176

Automatic well log correlation using neural networks  

E-print Network

is an iterative procedure for finding weights that minimize some error function. The most powerful leazning algorithm developed today (which is used in this project) is the error-back-propagation (EBP) algorithm sometimes referred to as the Generalized... training log). The total error (ET) is calculated in every pass. When the total error reaches an acceptable level, training halts. The error at every node is used to adjust network weights as described in the EBP algorithm. Weight adjustments should...

Habiballah, Walid Abdulrahim

2012-06-07

177

Gain stabilization for radioactivity well logging apparatus  

SciTech Connect

A new and improved gain stabilization system for radioactivity well logging apparatus is of the type having a scintillation crystal and optically coupled photomultiplier in a sonde to detect radiation in the borehole and formation elements in response to neutron bombardment. The gain stabilization system includes a light emitting diode driven by a pulser and furnishing scintillations to the photomultiplier, resulting in a stabilization pulse which is furnished to electronic circuitry at the surface for stabilization purposes.

Whatley, H.A.

1980-09-02

178

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

179

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

180

Chiral Gravity, Log Gravity and Extremal CFT  

E-print Network

We show that the linearization of all exact solutions of classical chiral gravity around the AdS3 vacuum have positive energy. Non-chiral and negative-energy solutions of the linearized equations are infrared divergent at second order, and so are removed from the spectrum. In other words, chirality is confined and the equations of motion have linearization instabilities. We prove that the only stationary, axially symmetric solutions of chiral gravity are BTZ black holes, which have positive energy. It is further shown that classical log gravity-- the theory with logarithmically relaxed boundary conditions --has finite asymptotic symmetry generators but is not chiral and hence may be dual at the quantum level to a logarithmic CFT. Moreover we show that log gravity contains chiral gravity within it as a decoupled charge superselection sector. We normally evaluate the Euclidean sum over geometries of chiral gravity and show that it gives precisely the holomorphic extremal CFT partition function. The modular invariance and integrality of the expansion coefficients of this partition function are consistent with the existence of an exact quantum theory of chiral gravity. We argue that the problem of quantizing chiral gravity is the holographic dual of the problem of constructing an extremal CFT, while quantizing log gravity is dual to the problem of constructing a logarithmic extremal CFT.

Alexander Maloney; Wei Song; Andrew Strominger

2009-03-26

181

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

182

Geostatistical Procedures for Developing Three-Dimensional Aquifer Models from Drillers' Logs  

NASA Astrophysics Data System (ADS)

The Hydrostratigraphic Drilling Record Assessment (HyDRA) project is developing procedures for employing the vast but highly qualitative hydrostratigraphic information contained in drillers' logs in the development of quantitative three-dimensional (3D) depictions of subsurface properties for use in flow and transport models to support groundwater management practices. One of the project's objectives is to develop protocols for 3D interpolation of lithological data from drillers' logs, properly accounting for the categorical nature of these data. This poster describes the geostatistical procedures developed to accomplish this objective. Using a translation table currently containing over 62,000 unique sediment descriptions encountered during the transcription of over 15,000 logs in the Kansas High Plains aquifer, the sediment descriptions are translated into 71 standardized terms, which are then mapped into a small number of categories associated with different representative property (e.g., hydraulic conductivity [K]) values. Each log is partitioned into regular intervals and the proportion of each K category within each interval is computed. To properly account for their compositional nature, a logratio transform is applied to the proportions. The transformed values are then kriged to the 3D model grid and backtransformed to determine the proportion of each category within each model cell. Various summary measures can then be computed from the proportions, including a proportion-weighted average K and an entropy measure representing the degree of mixing of categories within each cell. We also describe a related cross-validation procedure for assessing log quality.

Bohling, G.; Helm, C.

2013-12-01

183

Log-periodic route to fractal functions.  

PubMed

Log-periodic oscillations have been found to decorate the usual power-law behavior found to describe the approach to a critical point, when the continuous scale-invariance symmetry is partially broken into a discrete-scale invariance symmetry. For Ising or Potts spins with ferromagnetic interactions on hierarchical systems, the relative magnitude of the log-periodic corrections are usually very small, of order 10(-5). In growth processes [diffusion limited aggregation (DLA)], rupture, earthquake, and financial crashes, log-periodic oscillations with amplitudes of the order of 10% have been reported. We suggest a "technical" explanation for this 4 order-of-magnitude difference based on the property of the "regular function" g(x) embodying the effect of the microscopic degrees of freedom summed over in a renormalization group (RG) approach F(x)=g(x)+mu(-1)F(gamma x) of an observable F as a function of a control parameter x. For systems for which the RG equation has not been derived, the previous equation can be understood as a Jackson q integral, which is the natural tool for describing discrete-scale invariance. We classify the "Weierstrass-type" solutions of the RG into two classes characterized by the amplitudes A(n) of the power-law series expansion. These two classes are separated by a novel "critical" point. Growth processes (DLA), rupture, earthquake, and financial crashes thus seem to be characterized by oscillatory or bounded regular microscopic functions that lead to a slow power-law decay of A(n), giving strong log-periodic amplitudes. If in addition, the phases of A(n) are ergodic and mixing, the observable presents self-affine nondifferentiable properties. In contrast, the regular function of statistical physics models with "ferromagnetic"-type interactions at equilibrium involves unbound logarithms of polynomials of the control variable that lead to a fast exponential decay of A(n) giving weak log-periodic amplitudes and smoothed observables. PMID:11909200

Gluzman, S; Sornette, D

2002-03-01

184

14 CFR 125.407 - Maintenance log: Airplanes.  

...2014-01-01 false Maintenance log: Airplanes. 125.407 Section 125.407 ...OPERATIONS CERTIFICATION AND OPERATIONS: AIRPLANES HAVING A SEATING CAPACITY OF 20 OR...Reports 125.407 Maintenance log: Airplanes. (a) Each person who takes...

2014-01-01

185

14 CFR 125.407 - Maintenance log: Airplanes.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Maintenance log: Airplanes. 125.407 Section 125.407 ...OPERATIONS CERTIFICATION AND OPERATIONS: AIRPLANES HAVING A SEATING CAPACITY OF 20 OR...Reports 125.407 Maintenance log: Airplanes. (a) Each person who takes...

2013-01-01

186

14 CFR 125.407 - Maintenance log: Airplanes.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Maintenance log: Airplanes. 125.407 Section 125.407 ...OPERATIONS CERTIFICATION AND OPERATIONS: AIRPLANES HAVING A SEATING CAPACITY OF 20 OR...Reports 125.407 Maintenance log: Airplanes. (a) Each person who takes...

2012-01-01

187

14 CFR 125.407 - Maintenance log: Airplanes.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Maintenance log: Airplanes. 125.407 Section 125.407 ...OPERATIONS CERTIFICATION AND OPERATIONS: AIRPLANES HAVING A SEATING CAPACITY OF 20 OR...Reports 125.407 Maintenance log: Airplanes. (a) Each person who takes...

2010-01-01

188

14 CFR 125.407 - Maintenance log: Airplanes.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Maintenance log: Airplanes. 125.407 Section 125.407 ...OPERATIONS CERTIFICATION AND OPERATIONS: AIRPLANES HAVING A SEATING CAPACITY OF 20 OR...Reports 125.407 Maintenance log: Airplanes. (a) Each person who takes...

2011-01-01

189

Log Periodic Antennas Dr. S. X-Pol  

E-print Network

3/26/2009 1 Log Periodic Antennas INEL 5305 Dr. S. X-Pol Canal Frecuencia (MHz) Banda Frecuencia of the Log-Periodic Dipole Antenna" Variaciones used as a feed in reflector antennas Compact ultra broadband

Cruz-Pol, Sandra L.

190

Fluid-Temperature Logs for Selected Wells in Eastern Washington.  

National Technical Information Service (NTIS)

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...

K. L. Stoffel, S. Widness

1983-01-01

191

Acoustic Waveform Logging - Advances In Theory And Application  

E-print Network

Full-waveform acoustic logging has made significant advances in both theory and application in recent years, and these advances have greatly increased the capability of log analysts to measure the physical properties of ...

Cheng, C. H.

192

Are Log Permeabilities Gaussian? Their Increments May Tell  

NASA Astrophysics Data System (ADS)

We address the well-documented but heretofore little noticed and unexplained phenomenon that whereas the frequency distribution of log permeability data often appears to be Gaussian, those of corresponding increments may exhibit tails that decay as powers of -?, 1 < ? < 2, where ? is either constant or grows monotonically toward an asymptote, ?* , with increasing separation distance or lag. We illustrate the case of variable ? on 1-m scale log air permeabilities from pneumatic tests in 6 vertical and inclined boreholes completed in unsaturated fractured tuff near Superior, Arizona. We then show theoretically and demonstrate numerically, on synthetically generated data, that (1) whereas the case of constant ? is consistent with relatively regular ?-stable fields having increments subordinated to truncated fractional Gaussian noise (tfGn), (2) the case of variable ? is consistent with highly irregular ?*-stable fields, punctuated by spurious jumps, subordinated to truncated fractional Brownian motion (tfBm). We describe a procedure to estimate the parameters of univariate distributions characterizing such fields and apply it to the above data. Our analysis suggests that the data are consistent with an ?*-stable field characterized by ?* slightly smaller than 2, which is easily confused with a Gaussian field (characterized by constant ? = 2). The irregular (jumpy) nature of such a field is typical of observed fractured rock properties. We propose that distributions of earth and environmental variables be inferred jointly and consistently from measured values of these variables, and their increments, in a manner supported by theory as we do here.

Neuman, S. P.; Riva, M.; Guadagnini, A.

2011-12-01

193

Geostatistical Simulation of Acoustic Log Data for Seismic Depth Conversion  

SciTech Connect

Seismic reflection methods measure the time a seismic wave takes to travel through the ground, from the user defined source to a series of signal monitoring sensors known as geophones. The measured times need to be depth converted to allow for integration with other geological data. In order to convert from time to depth, an estimate of the rock volume velocity field must be made. The velocity field estimate can be made by assignment of velocity estimates to a geological model independent of the seismic processing. This article presents the results of using the acoustic geophysical log data extrapolated via sequential Gaussian simulation to derive the velocity field. The uncertainties associated with the velocity estimates were significant and provided the means to assess confidence limits for the actual depth determination. The technique is assessed by application to a major coal deposit, approximately 2.1 m thick and 210 m deep. Considering only the uncertainty associated with estimating the velocity field, half of the confidence interval values showed approximately 1 m of uncertainty in depth. The application of sequential Gaussian simulation to model the 3D distribution of acoustic velocity can be extended to other geophysical log parameters or derived estimates.

Koppe, Vanessa Cerqueira; Costa, Joao Felipe Coimbra Leite, E-mail: jfelipe@ufrgs.br; Koppe, Jair Carlos; Gambin, Fernando [UFRGS, Mining Engineering Department (Brazil); Fallon, Gary; Davies, Nick [Now Geophysical Resources and Services, Formerly Xstrata Inc (Australia)

2007-12-15

194

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

195

Knowledge-based stratigraphic well-log correlation  

E-print Network

-base. The front-end-processor abstracts symbols from digitized well-log data, identifies lithologic zones, and attaches attributes to the lithologic zones. The correlation process uses the higher level information that is abstracted from the well-log data...-base. The front-end-processor abstracts symbols from digitized well-log data, identifies lithologic zones, and attaches attributes to the lithologic zones. The correlation process uses the higher level information that is abstracted from the well-log data...

Denton, Michael A.

2012-06-07

196

Applying multiwell normalization in open hole log analysis  

E-print Network

. However, these logs were difficult to interpret and unduly affected by borehole conditions. An effort to reduce the borehole effects, and improve ease of interpretation led to the development of "focused" logs and the laterolog". In 1949 Henri Doll.... However, these logs were difficult to interpret and unduly affected by borehole conditions. An effort to reduce the borehole effects, and improve ease of interpretation led to the development of "focused" logs and the laterolog". In 1949 Henri Doll...

Sinanan, Haydn Brent

2012-06-07

197

Interpretation of well log response in the Austin chalk  

E-print Network

-m The intermediate resistivities are the re ult of water re-entering the pores following hydrocarbon migration. Fractures were identified from standard logs by comparing porosity log responses with the gamma-ray, caliper and resistivity logs. An increase... in density and neutron porosities relative to sonic transit time indicate the presence of secondary porosity due to fracturing. Comparison with the gamma-ray log helps to distinguish secondary porosity from an increase in total porosity due to increased...

Hinds, Gregory Scott

2012-06-07

198

Expected Value  

NSDL National Science Digital Library

This online, interactive lesson on expected value provides examples, exercises, and applets in which students will explore relationships between the expected value of real-valued random variables and the center of the distribution. Students will also examine how expected values can be used to measure spread and correlation.

Siegrist, Kyle

2008-12-24

199

Log-Periodic Antenna Design Using Electromagnetic Simulations  

E-print Network

Log-Periodic Antenna Design Using Electromagnetic Simulations ?zgür Ergül* and Levent Gürel@ee.bilkent.edu.tr, lgurel@bilkent.edu.tr) 1. Introduction Log-periodic (LP) antennas are important with their ability to (not instead of) theoretical principles will be demonstrated. Figure 1: (a) Log-periodic antenna design

Gürel, Levent

200

Nonplanar trapezoidal tooth log-periodic antennas: Design and electromagnetic  

E-print Network

Nonplanar trapezoidal tooth log-periodic antennas: Design and electromagnetic modeling O¨ zgu 2005. [1] Nonplanar trapezoidal tooth log-periodic (LP) antennas are investigated by combining log-periodic antennas: Design and electromagnetic modeling, Radio Sci., 40, RS5010, doi:10.1029/2004RS

Gürel, Levent

201

CIRCULAR ARRAYS OF LOG-PERIODIC ANTENNAS FOR BROADBAND APPLICATIONS  

E-print Network

CIRCULAR ARRAYS OF LOG-PERIODIC ANTENNAS FOR BROADBAND APPLICATIONS ¨Ozg¨ur Erg¨ul1 and Levent G, Turkey Email: ergul@ee.bilkent.edu.tr, lgurel@bilkent.edu.tr ABSTRACT Circular arrays of log-periodic (LP: Log-periodic antennas; circular antenna ar- rays; genetic algorithms; multilevel fast multipole algo

Gürel, Levent

202

Log homogeneous compactifications of some classical groups Mathieu Huruguen  

E-print Network

Log homogeneous compactifications of some classical groups Mathieu Huruguen Abstract We generalize in positive characteristics some results of Bien and Brion on log homogeneous compactifications of a homogeneous space under the action of a con- nected reductive group. We also construct an explicit smooth log

Huruguen, Mathieu

203

Why, What, and How to Log? Lessons from LISTEN  

ERIC Educational Resources Information Center

The ability to log tutorial interactions in comprehensive, longitudinal, fine-grained detail offers great potential for educational data mining--but what data is logged, and how, can facilitate or impede the realization of that potential. We propose guidelines gleaned over 15 years of logging, exploring, and analyzing millions of events from

Mostow, Jack; Beck, Joseph E.

2009-01-01

204

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

205

The Learning Log as an Integrated Instructional Assessment Tool.  

ERIC Educational Resources Information Center

Use of student learning logs is recommended as a means for both students and teacher to assess second-language learning. The approach encourages learners to analyze their learning difficulties and plan for overcoming them. Incorporated into portfolios, logs can be used to analyze progress. Sample log sheet and chart used as a framework for

Topaz, Beverley

1997-01-01

206

The ROSAT Brightest Cluster Sample - I. The compilation of the sample and the cluster log N-log S distribution  

NASA Astrophysics Data System (ADS)

We present a 90 per cent flux-complete sample of the 201 X-ray-brightest clusters of galaxies in the northern hemisphere (delta>=0 deg), at high Galactic latitudes (|b|>=20 deg), with measured redshifts z<=0.3 and fluxes higher than 4.4x10^-12 erg cm^-2 s^-1 in the 0.1-2.4 keV band. The sample, called the ROSAT Brightest Cluster Sample (BCS), is selected from ROSAT All-Sky Survey data and is the largest X-ray-selected cluster sample compiled to date. In addition to Abell clusters, which form the bulk of the sample, the BCS also contains the X-ray-brightest Zwicky clusters and other clusters selected from their X-ray properties alone. Effort has been made to ensure the highest possible completeness of the sample and the smallest possible contamination by non-cluster X-ray sources. X-ray fluxes are computed using an algorithm tailored for the detection and characterization of X-ray emission from galaxy clusters. These fluxes are accurate to better than 15 per cent (mean 1sigma error). We find the cumulative logN-logS distribution of clusters to follow a power law kappa S^alpha with alpha=1.31^+0.06_-0.03 (errors are the 10th and 90th percentiles) down to fluxes of 2x10^-12 erg cm^-2 s^-1, i.e. considerably below the BCS flux limit. Although our best-fitting slope disagrees formally with the canonical value of -1.5 for a Euclidean distribution, the BCS logN-logS distribution is consistent with a non-evolving cluster population if cosmological effects are taken into account. Our sample will allow us to examine large-scale structure in the northern hemisphere, determine the spatial cluster-cluster correlation function, investigate correlations between the X-ray and optical properties of the clusters, establish the X-ray luminosity function for galaxy clusters, and discuss the implications of the results for cluster evolution.

Ebeling, H.; Edge, A. C.; Bohringer, H.; Allen, S. W.; Crawford, C. S.; Fabian, A. C.; Voges, W.; Huchra, J. P.

1998-12-01

207

VAFLE: visual analytics of firewall log events  

NASA Astrophysics Data System (ADS)

In this work, we present VAFLE, an interactive network security visualization prototype for the analysis of firewall log events. Keeping it simple yet effective for analysts, we provide multiple coordinated interactive visualizations augmented with clustering capabilities customized to support anomaly detection and cyber situation awareness. We evaluate the usefulness of the prototype in a use case with network traffic datasets from previous VAST Challenges, illustrating its effectiveness at promoting fast and well-informed decisions. We explain how a security analyst may spot suspicious traffic using VAFLE. We further assess its usefulness through a qualitative evaluation involving network security experts, whose feedback is reported and discussed.

Ghoniem, Mohammad; Shurkhovetskyy, Georgiy; Bahey, Ahmed; Otjacques, Benot.

2013-12-01

208

Using Web Logs in the Science Classroom  

NSDL National Science Digital Library

As educators we must ask ourselves if we are meeting the needs of todays 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, youll learn why web logs (also called blogs) are an important Web 2.0 tool in your science classroom and how they can be created and used to increase science literacy by engaging students in writing, problem solving, and collaboration. These tools will effectively prepare students to work in todays social, interactive, online world.

2009-11-01

209

The Borneo Project : Indonesia Fails to Stop Illegal Logging, Report Says Indonesia Fails to Stop Illegal Logging, Report Says  

E-print Network

The Borneo Project : Indonesia Fails to Stop Illegal Logging, Report Says Indonesia Fails to Stop Illegal Logging, Report Says by Irwan Firdaus, The Associated Press January 15th, 2003 JAKARTA, Indonesia -- Corruption in Indonesia's police and military has contributed to a surge in illegal logging that has

210

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

211

Fractals and log-periodic corrections applied to masses and energy levels of several nuclei  

E-print Network

A contribution is presented to the application of fractal properties and log-periodic corrections to the masses of several nuclei (isotopes or isotones), and to the energy levels of some nuclei. The fractal parameters $\\alpha$ and $\\lambda$ are not randomly distributed, but take a small number of values, common also with the values extracted previously from fractal distributions of quark, lepton, and hadronic masses. Several masses of still unobserved nuclei are tentatively predicted.

Tatischeff, Boris

2011-01-01

212

Generalized q analysis of log-periodicity: applications to critical ruptures.  

PubMed

We introduce a generalization of the q analysis, which provides a nonparametric tool for the description and detection of log-periodic structures associated with discrete scale invariance. We use this generalized q analysis to construct a signature called the (H,q) derivative of discrete scale invariance, which we use to detect the log-periodicity in the cumulative energy release preceding the rupture of five pressure tanks made of composite carbon-matrix material. We investigate the significance level of the spectral Lomb periodogram of the optimal (H,q) derivative. We confirm and strengthen previous parametric results that the cumulative energy release exhibits log-periodicity before rupture. However, our tests to use this method as a scheme for the prediction of the critical value of the stress at rupture are not encouraging. PMID:12443263

Zhou, Wei-Xing; Sornette, Didier

2002-10-01

213

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

214

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

215

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

216

Dual excitation acoustic paramagnetic logging tool  

DOEpatents

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

217

Peoria`s log recycling program  

SciTech Connect

The City of Peoria had a problem: thousands of cubic yards of wood waste--tree limbs, logs, and trimmings stockpiled as a result of three years of operations and storms. They were faced with a potentially costly dilemma: how to dispose of this material without breaking the law or the budget? With intergovernmental cooperation and perseverance, they did it. The Peoria Park District had a problem, too. Between 1990 and 1992, three major storms downed and severely damaged many of the area`s trees. In addition, the city and Park District annually cut approximately 350 to 400 trees, as well as annual trimming in parks and along rights-of-way. The City had been hauling small and manageable material to the local compost site, but 5,500 cu yd of large-diameter trees and limbs remained stored on City property. The Park District had been pushing its material into a large ravine at one of the parks. But, in 1992, the Illinois Environmental Protection Agency ordered them to stop this practice. With the closure of its park disposal site, the Park District, like the city, began stockpiling. After reviewing various options, the city refocused on log recycling.

McKinley, D.W.

1994-11-01

218

Principle and geometric precision of photographic geological logging of tunnels  

NASA Astrophysics Data System (ADS)

Considering the problem of engineering geological logging technique by means of sketching at the work site, this paper presents a photographic geological logging technique based on photogrammetry as well as engineering geology. The principles, methods, and working process have been discussed, and the photographic geological logging precision of a tunnel and its estimation method have been researched. The theoretical and experimental analysis shows that the precision of the digital unfolded image map of tunnel automatically generated by the photographic geological logging method is sufficient for serving as the logging base map. Besides, the measurement precision of unfolded images or stereopairs meets the requirements of geological attitude measurement. The new technique of photographic geological logging proposed in this paper is expected to replace the current sketch way of engineering geological logging on site, with the operation mode converted from manual operation to computer-aided operation and informatized management.

Li, Hao; Zhang, Rong-Chun; Yang, Biao; Wu, Ming-Fei

2014-01-01

219

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 m/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

220

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 ...

221

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

222

Squirt flow influence on sonic log parameters  

NASA Astrophysics Data System (ADS)

Most sedimentary rocks contain movable fluid in the pores. Hydrodynamic effects due to wave-induced oscillatory fluid flow can lead to significant changes of velocities and attenuations of elastic waves in these rocks. In this paper, we consider the influence of a squirt flow (local flow between the pores of different compressibility) on the sonic log response. The calculations are performed using a unified model describing the joint influence of squirt flow and Biot's global flow. The results show that the influence of the squirt flow increases with increase of a signal frequency. This influence is relatively small in the case of the Stoneley wave but it is significant in the case of P and S waves.

Markova, I.; Ronquillo Jarillo, G.; Markov, M.; Gurevich, B.

2014-02-01

223

Tolerance bounds for log gamma regression models  

NASA Technical Reports Server (NTRS)

The present procedure for finding lower confidence bounds for the quantiles of Weibull populations, on the basis of the solution of a quadratic equation, is more accurate than current Monte Carlo tables and extends to any location-scale family. It is shown that this method is accurate for all members of the log gamma(K) family, where K = 1/2 to infinity, and works well for censored data, while also extending to regression data. An even more accurate procedure involving an approximation to the Lawless (1982) conditional procedure, with numerical integrations whose tables are independent of the data, is also presented. These methods are applied to the case of failure strengths of ceramic specimens from each of three billets of Si3N4, which have undergone flexural strength testing.

Jones, R. A.; Scholz, F. W.; Ossiander, M.; Shorack, G. R.

1985-01-01

224

Simulation Control Graphical User Interface Logging Report  

NASA Technical Reports Server (NTRS)

One of the many tasks of my project was to revise the code of the Simulation Control Graphical User Interface (SIM GUI) to enable logging functionality to a file. I was also tasked with developing a script that directed the startup and initialization flow of the various LCS software components. This makes sure that a software component will not spin up until all the appropriate dependencies have been configured properly. Also I was able to assist hardware modelers in verifying the configuration of models after they have been upgraded to a new software version. I developed some code that analyzes the MDL files to determine if any error were generated due to the upgrade process. Another one of the projects assigned to me was supporting the End-to-End Hardware/Software Daily Tag-up meeting.

Hewling, Karl B., Jr.

2012-01-01

225

The usage of velocity deviation log (VDL) in order to recognize porosity types and trends in permeability of the Asmari and Jahrum reservoirs units in the KHESHT oil field (Kazeroon)  

NASA Astrophysics Data System (ADS)

Porosity value is one of the most important factors which determine the oil volume and also basis of economical or uneconomical calculation of a distinct oil field. By combining the logs, nowadays, very detailed and precise issues could be recognized, for instance we could point examining of porosity types and trends in permeability by using the velocity deviation log (VDL). Velocity devotion log which is calculated by combination sonic log with the Norton porosity or density log provides tool to obtain down hole information on the predominate pore type in carbonates the log can be use to trace the down hole distribution of digenetic processes and to estimate trends in permeability. Generally speaking, porosity and velocity have inverted relationship; nevertheless the type of porosity changes this relationship. In order to establish the velocity deviation log at first; by using the Wyllie equation, porosity log was exchanged to synthetic velocity log, acquired real velocity difference from sonic log and the acquired synthetic velocity from the porosity log is expressed as velocity deviation log. With log being deviated to left and right, the type of porosity would be identified .this method is applied for the Asmari and Jahrum reservoirs units of the Khesht oil field in Kazeroon (Fars),And in one of the wells. This log approves the boundary of Formations which is along with unconformities and even zoning whether is based on porosity value or change of lithology, and also the results which are gotten from the log have close similarities with the results of thin section studies in terms of porosity. Drawing of log and calculation of petrophysic parameters are done by Geolog software.

Morshedi Pour, Amin; Lotfpour, Masoud; Enayati, Aliasghar

2010-05-01

226

Petrophysical analysis of geophysical logs of the National Drilling Company-U.S. Geological Survey ground-water research project for Abu Dhabi Emirate, United Arab Emirates  

USGS Publications Warehouse

A program of borehole-geophysical logging was implemented to supply geologic and geohydrologic information for a regional ground-water investigation of Abu Dhabi Emirate. Analysis of geophysical logs was essential to provide information on geohydrologic properties because drill cuttings were not always adequate to define lithologic boundaries. The standard suite of logs obtained at most project test holes consisted of caliper, spontaneous potential, gamma ray, dual induction, microresistivity, compensated neutron, compensated density, and compensated sonic. Ophiolitic detritus from the nearby Oman Mountains has unusual petrophysical properties that complicated the interpretation of geophysical logs. The density of coarse ophiolitic detritus is typically greater than 3.0 grams per cubic centimeter, porosity values are large, often exceeding 45 percent, and the clay fraction included unusual clays, such as lizardite. Neither the spontaneous-potential log nor the natural gamma-ray log were useable clay indicators. Because intrinsic permeability is a function of clay content, additional research in determining clay content was critical. A research program of geophysical logging was conducted to determine the petrophysical properties of the shallow subsurface formations. The logging included spectral-gamma and thermal-decay-time logs. These logs, along with the standard geophysical logs, were correlated to mineralogy and whole-rock chemistry as determined from sidewall cores. Thus, interpretation of lithology and fluids was accomplished. Permeability and specific yield were calculated from geophysical-log data and correlated to results from an aquifer test. On the basis of results from the research logging, a method of lithologic and water-resistivity interpretation was developed for the test holes at which the standard suite of logs were obtained. In addition, a computer program was developed to assist in the analysis of log data. Geohydrologic properties were estimated, including volume of clay matrix, volume of matrix other than clay, density of matrix other than clay, density of matrix, intrinsic permeability, specific yield, and specific storage. Geophysical logs were used to (1) determine lithology, (2) correlate lithologic and permeable zones, (3) calibrate seismic reprocessing, (4) calibrate transient-electromagnetic surveys, and (5) calibrate uphole-survey interpretations. Logs were used at the drill site to (1) determine permeability zones, (2) determine dissolved-solids content, which is a function of water resistivity, and (3) design wells accordingly. Data and properties derived from logs were used to determine transmissivity and specific yield of aquifer materials.

Jorgensen, Donald G.; Petricola, Mario

1994-01-01

227

Maximum likelihood borehole corrections for dual-detector density logs  

SciTech Connect

This report discusses Dual-detector density logs which have been used in the petroleum industry for years. The tool was designed with a second detector to allow compensation for the effect of a layer of mudcake between the tool and the formation being measured. The compensation algorithm commonly used calculates the correction to apply to the density measured by the long-spaced detector as proportional to the difference in the densities measured by the two detectors. The coefficient of proportionality is determined from experimental data taken with the tool in a fluid-filled hole of 15 to 40 cm diameter, with uniform thickness sheets of various materials simulating the mudcake. In applying this technology for the Containment program at the Department of Energy Nevada Test Site (NTS) we have discovered two problems. First, we frequently log in air-filled holes much larger than 40 cm. Second, the gap, or layer, is rarely uniform with depth or vertical position on the face of the tool. We have developed a method to determine the proper amount of correction dynamically. No experimental data on the gap effect are needed as long as the two detectors are calibrated to read the proper density when the gap is zero. The method assumes that the form of the equation used in the standard algorithm is correct, but uses the variation of the two density signals with depth to determine the appropriate value of the coefficient, assuming true density varies more slowly than the gap effects. This new, maximum likelihood, method appears to work better than the standard method in both fluid and air-filled holes where the borehole wall is rough and no mudcake is present. It cannot, however, correct for a uniform mudcake or air gap, and so complements but does not replace the standard method.

Carlson, R.C.

1993-10-01

228

Geophysical well logging operations and log analysis in Geothermal Well Desert Peak No. B-23-1  

SciTech Connect

Geothermal Well Desert Peak No. B-23-1 was logged by Dresser Atlas during April/May 1979 to a total depth of 2939 m (9642 ft). A temperature of 209/sup 0/C (408/sup 0/F) was observed on the maximum thermometer run with one of the logging tools. Borehole tools rated to a maximum temperature of 204.4/sup 0/C (400/sup 0/F) were utilized for logging except for the Densilog tool, which was from the other set of borehole instruments, rated to a still higher temperature, i.e., 260/sup 0/C (500/sup 0/F). The quality of the logs recorded and the environmental effects on the log response have been considered. The log response in the unusual lithologies of igneous and metamorphic formations encountered in this well could be correlated with the drill cutting data. An empirical, statistical log interpretation approach has made it possible to obtain meaningful information on the rocks penetrated. Various crossplots/histograms of the corrected log data have been generated on the computer. These are found to provide good resolution between the lithological units in the rock sequence. The crossplotting techniques and the statistical approach were combined with the drill cutting descriptions in order to arrive at the lithological characteristics. The results of log analysis and recommendations for logging of future wells have been included.

Sethi, D.K.; Fertl, W.H.

1980-03-01

229

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

SciTech Connect

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 and calibration. A sample suite of logs is presented that demonstrates correlation of geological formations from borehole to borehole, the definition of zones of altered mineralogy, and the quantitative estimates of rock properties. We show the results of an exploratory calculation of porosity and water saturation based upon density and epithermal neutron logs. Comparison of the results with a few core samples is encouraging, particularly because the logs can provide continuous data in boreholes where core samples are not available. 9 refs., 4 figs.

Schimschal, U.; Nelson, P.H.

1991-05-01

230

Color images of Kansas subsurface geology from well logs  

USGS Publications Warehouse

Modern wireline log combinations give highly diagnostic information that goes beyond the basic shale content, pore volume, and fluid saturation of older logs. Pattern recognition of geology from logs is made conventionally through either the examination of log overlays or log crossplots. Both methods can be combined through the use of color as a medium of information by setting the three color primaries of blue, green, and red light as axes of three dimensional color space. Multiple log readings of zones are rendered as composite color mixtures which, when plotted sequentially with depth, show lithological successions in a striking manner. The method is extremely simple to program and display on a color monitor. Illustrative examples are described from the Kansas subsurface. ?? 1986.

Collins, D.R.; Doveton, J.H.

1986-01-01

231

Sustainability of reduced-impact logging in the Eastern Amazon  

Microsoft Academic Search

Damage caused by reduced-impact logging (RIL) was assessed in 18 plots 1ha each in a terra firme rain forest of Eastern Amazon (Brazil, Paragominas). Mean logging intensity was 6treesha?1 and the resulting commercial volume 21m3ha?1. On average, logging damage affected 16% of the original stand while skidtrails occupied 7% (661m2ha?1) of forest soil area. Canopy openness doubled to a mean

Plinio Sist; Fabricio Nascimento Ferreira

2007-01-01

232

Western tight gas sands advanced logging workshop proceedings  

SciTech Connect

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 logging research program. Sixteen papers and abstracts are included together with discussions. Separate abstracts have been prepared for the 12 papers. (DLC)

Jennings, J B; Carroll, Jr, H B [eds.

1982-04-01

233

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

234

Effects of postfire salvage logging on deadwood-associated beetles.  

PubMed

In Canada and the United States pressure to recoup financial costs of wildfire by harvesting burned timber is increasing, despite insufficient understanding of the ecological consequences of postfire salvage logging. We compared the species richness and composition of deadwood-associated beetle assemblages among undisturbed, recently burned, logged, and salvage-logged, boreal, mixed-wood stands. Species richness was lowest in salvage-logged stands, largely due to a negative effect of harvesting on the occurrence of wood- and bark-boring species. In comparison with undisturbed stands, the combination of wildfire and logging in salvage-logged stands had a greater effect on species composition than either disturbance alone. Strong differences in species composition among stand treatments were linked to differences in quantity and quality (e.g., decay stage) of coarse woody debris. We found that the effects of wildfire and logging on deadwood-associated beetles were synergistic, such that the effects of postfire salvage logging could not be predicted reliably on the basis of data on either disturbance alone. Thus, increases in salvage logging of burned forests may have serious negative consequences for deadwood-associated beetles and their ecological functions in early postfire successional forests. PMID:20735453

Cobb, T P; Morissette, J L; Jacobs, J M; Koivula, M J; Spence, J R; Langor, D W

2011-02-01

235

Compilation of network activity logs on a DECnet host  

SciTech Connect

Log files are created for all incoming connection requests on a DECnet host. These log files contain connection data such as the requesting source, destination, and throughput. The procedures (referred to as collect software) outlined in this report, were written to collect these log files, to extract the essential information, and to condense the data into one-line records. The two VAX/VMS systems at SNLA that currently run these procedures compile network transaction logs on a weekly basis. This document is intended for VAX/VMS system managers who wish to install, and possibly modify, this software.

George, M.

1987-07-01

236

Hydraulic parameters estimation from well logging resistivity and geoelectrical measurements  

NASA Astrophysics Data System (ADS)

In this paper, a methodology is suggested for deriving hydraulic parameters, such as hydraulic conductivity or transmissivity combining classical hydrogeological data with geophysical measurements. Estimates values of transmissivity and conductivity, with this approach, can reduce uncertainties in numerical model calibration and improve data coverage, reducing time and cost of a hydrogeological investigation at a regional scale. The conventional estimation of hydrogeological parameters needs to be done by analyzing wells data or laboratory measurements. Furthermore, to make a regional survey many wells should be considered, and the location of each one plays an important role in the interpretation stage. For this reason, the use of geoelectrical methods arises as an effective complementary technique, especially in developing countries where it is necessary to optimize resources. By combining hydraulic parameters from pumping tests and electrical resistivity from well logging profiles, it was possible to adjust three empirical laws in a semi-confined alluvial aquifer in the northeast of the province of Buenos Aires (Argentina). These relations were also tested to be used with surficial geoelectrical data. The hydraulic conductivity and transmissivity estimated in porous material were according to expected values for the region (20 m/day; 457 m2/day), and are very consistent with previous results from other authors (25 m/day and 500 m2/day). The methodology described could be used with similar data sets and applied to other areas with similar hydrogeological conditions.

Perdomo, S.; Ainchil, J. E.; Kruse, E.

2014-06-01

237

Inflow and outflow signatures in flowing wellbore electrical conductivity logs  

SciTech Connect

Flowing wellbore electrical-conductivity logging provides a means to determine hydrologic properties of fractures, fracture zones, or other permeable layers intersecting a borehole in saturated rock. The method involves analyzing the time-evolution of fluid electrical-conductivity logs obtained while the well is being pumped and yields information on the location, hydraulic transmissivity, and salinity of permeable layers, as well as their initial (or ambient) pressure head. Earlier analysis methods were restricted to the case in which flows from the permeable layers or fractures were directed into the borehole. More recently, a numerical model for simulating flowing-conductivity logging was adapted to permit treatment of both inflow and outflow, including analysis of natural regional flow in the permeable layer. However, determining the fracture properties with the numerical model by optimizing the match to the conductivity logs is a laborious trial-and-error procedure. In this paper, we identify the signatures of various inflow and outflow features in the conductivity logs to expedite this procedure and to provide physical insight for the analysis of these logs. Generally, inflow points are found to produce a distinctive signature on the conductivity logs themselves, enabling the determination of location, inflow rate, and ion concentration in a straightforward manner. Identifying outflow locations and flow rates, on the other hand, can be done with a more complicated integral method. Running a set of several conductivity logs with different pumping rates (e.g., half and double the original pumping rate) provides further information on the nature of the feed points. In addition to enabling the estimation of flow parameters from conductivity logs, an understanding of the conductivity log signatures can aid in the design of follow-up logging activities.

Doughty, Christine; Tsang, Chin-Fu

2002-08-28

238

Logging and Fire Effects in Siberian Boreal Forests  

NASA Astrophysics Data System (ADS)

The Russian boreal zone supports a huge terrestrial carbon pool. Moreover, it is a tremendous reservoir of wood products concentrated mainly in Siberia. 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 increase landscape complexity and fire hazard. We investigated a number of sites in different regions of Siberia to evaluate the impacts of fire and logging on fuel loads, carbon emissions, tree regeneration, soil respiration, and microbocenosis. We found large variations of fire and logging effects among regions depending on growing conditions and type of logging activity. Partial logging had no negative impact on forest conditions and carbon cycle. Illegal logging resulted in increase of fire hazard, and higher carbon emissions than legal logging. The highest fuel loads and carbon emissions were found on repeatedly burned unlogged sites where first fire resulted in total tree mortality. Repeated fires together with logging activities in drier conditions and on large burned sites resulted in insufficient regeneration, or even total lack of tree seedlings. Soil respiration was less on both burned and logged areas than in undisturbed forest. The highest structural and functional disturbances of the soil microbocenosis were observed on logged burned sites. Understanding current interactions between fire and logging is important for modeling ecosystem processes and for managers to develop strategies of sustainable forest management. Changing patterns in the harvest of wood products increase landscape complexity and can be expected to increase 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, E.; Buryak, L.; Ivanova, G.; Kalenskaya, O.; Bogorodskaya, A.; Zhila, S.; McRae, D.; Conard, S. G.

2013-12-01

239

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

240

Saving big bucks with your log sheets  

SciTech Connect

This article speaks to a common problem in a lot of industrial and institutional boilerhouses. Most boilerhouses do an excellent job at collecting information. Circular chart recorders churn out pressures, temperatures, and flows for everything from steam to natural gas to city water consumption. At most facilities, this stuff all gets chucked into a drawer or file cabinet daily. Have you ever wondered why you collect and record what you do? What were people thinking when the existing logs were set up? This article attempts to challenge the original thought process and hopes to evoke in the reader a renewed vision of what should be collected, how, and then what can be done with it. The goal of this article is not to define new and expensive data acquisition or control system projects. It is instead to show how to develop systems that only require paper, pencils, and people who are motivated and care. These people are probably already being paid to do most of this work. Experience is that if these people are treated with respect and given some simple tools they will do amazing things beyond what was thought possible. This is a low-tech humanistic approach that has a fabulous rate of return. It`s also something that can be immediately implemented.

Puskar, J.R. [CEC Consultants, Inc., Cleveland, OH (United States)

1999-07-01

241

Log-Linear Models Noah A. Smith  

E-print Network

as follows: Pr (x, y) = exp · f(x, y) x ,y exp · f(x , y ) (1) where is a R-valued vector of feature weights and f is a function that maps pairs (x, y) to a nonnegative R-valued feature vector errors are corrected. I do not address iterative scaling (Darroch and Ratcliff, 1972), but rather give

Smith, Noah

242

Comparative measurements between a new logging tool and a reference instrument.  

PubMed

Measurements were performed on reference samples (D2O-H2O mixtures) and on highly heterogeneous rocks (Vosges sandstone) with a new logging tool designed to give access to a high spatial resolution, below 1.5 cm on the vertical scale, for a toroidal sensitive volume of 20 cm3. The results were compared to measurements obtained on a clinical magnetic resonance imaging (MRI) equipment working at the same frequency (4.3 MHz). T2 differences as high as 30% were observed for the reference samples; the shortest values were obtained with the logging tool. Porosity profiles of the rock samples were also compared to reference profiles obtained with a conventional computed tomography (CT) scanner. Both nuclear magnetic resonance (NMR) measurements underevaluate porosity by 2-4% for short T2 values (< 10 ms). PMID:9803916

Locatelli, M; Mathieu, H; Bobroff, S; Guillot, G; Zinszner, B

1998-01-01

243

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

244

Artifactual log-periodicity in finite size data: Relevance for earthquake aftershocks  

Microsoft Academic Search

The recently proposed discrete scale invariance and its associated\\u000alog-periodicity are an elaboration of the concept of scale invariance in which\\u000athe system is scale invariant only under powers of specific values of the\\u000amagnification factor. We report on the discovery of a novel mechanism for such\\u000alog-periodicity relying solely on the manipulation of data. This ``synthetic''\\u000ascenario for log-periodicity

Y. Huang; A. Johansen; M. W. Lee; H. Saleur; D. Sornette

1999-01-01

245

Log-periodic oscillations for biased diffusion on random lattice  

Microsoft Academic Search

Random walks with a fixed bias direction on randomly diluted cubic lattices far above the percolation threshold exhibit log-periodic oscillations in the effective exponent versus time. A scaling argument accounts for the numerical results in the limit of large biases and small dilution and shows the importance of the interplay of these two ingredients in the generation of the log-periodicity.

Dietrich Stauffer; Didier Sornette

1998-01-01

246

Complex Exponents and Log-Periodic Corrections in Frustrated Systems  

Microsoft Academic Search

Recently, it has been observed that rupture processes in highly disordered media and earthquakes exhibit universal log-periodic corrections to scaling. We argue that such corrections should actually be present in a wide class of disordered systems and provide a theoretical framework to handle them. At the naivest level, a natural explanation for log-periodic corrections is discrete scale invariance, a notion

H. Saleur; D. Sornette

1996-01-01

247

Significance of log-periodic precursors to financial crashes  

Microsoft Academic Search

We clarify the status of log-periodicity associated with speculative bubbles preceding financial crashes. In particular, we address Feigenbaum's [2001] criticism and show how it can be rebuked. Feigenbaum's main result is as follows: ``the hypothesis that the log-periodic component is present in the data cannot be rejected at the 95% confidence level when using all the data prior to the

Didier Sornette; Anders Johansen

2001-01-01

248

Please consider the environment before printing Amazon logging industry declines  

E-print Network

Shows Produced By Bing Travel! Rain Forest Mapping Software for Mapping and Managing REDD Forest on the Amazon logging industry in Brazil, reports a major new assessment conducted by Imazon and the Brazilian Forest Service. The report, "Logging in Brazilian Amazon: production, revenues and markets" (A atividade

249

Condition and fate of logged forests in the Brazilian Amazon  

E-print Network

of Brazil depends on the maintenance of adequate timber volume and growth in healthy forests. Using not be sustained. Brazil forest disturbance remote sensing selective logging tropical forest Satellite observationsCondition and fate of logged forests in the Brazilian Amazon Gregory P. Asner* , Eben N. Broadbent

Camara, Gilberto

250

33 CFR 207.370 - Big Fork River, Minn.; logging.  

Code of Federal Regulations, 2010 CFR

...flatboats, and other small craft. (b) A sufficient force of men must accompany each log drive to prevent the formation of log jams and to maintain an open channel for navigation. (c) This section shall remain in force until modified or rescinded....

2010-07-01

251

DIALOG: Distributed Auditing Logs Christoph Ringelstein and Steffen Staab  

E-print Network

) and sticky logging. DIALOG is a method for auditing the distributed processing of data in service- orientedDIALOG: Distributed Auditing Logs Christoph Ringelstein and Steffen Staab ISWeb Working Group different organizations into one comprehensive, integrated workflow leading to an agile virtual organization

Staab, Steffen

252

Vine management for reduced-impact logging in eastern Amazonia  

Microsoft Academic Search

The presence of vines interconnecting the canopies of tropical forest trees has been thought to increase the damage to neighboring trees when a tree is felled during selective logging, resulting in larger canopy gaps and possibly prejudicting future timber harvests. To ameliorate this problem, vine cutting prior to logging has been recommended as a forest management tool. However, at present,

Edson Vidal; Jennifer Johns; Jeffrey J. Gerwing; Paulo Barreto; Christopher Uhl

1997-01-01

253

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

254

Thermal conductivity from core and well log data  

Microsoft Academic Search

A number of attempts have been made to determine thermal conductivity from well log data, including direct empirical relationships between measured properties and more complex models based on mixing laws. The latter require interpretation of well log data in terms of lithology and porosity prior to thermal conductivity estimation. While the second approach is more universally applicable there is general

A. Hartmann; V. Rath; C. Clauser

2003-01-01

255

2010 Summary of UCSB's Scientific Diving # Divers Logging Dives 121  

E-print Network

,946 109 Dives by AAUS Depth Range Depth Range Dives Logged Number of Divers Logging Dives 0-30 feet 2,093 109 31-60 feet 3,735 108 61-100 feet 436 48 101-130 feet 52 10 131-150 feet 5 3 191+ feet 0 0

Becker, Luann

256

Web Log Analysis: A Study of Instructor Evaluations Done Online  

ERIC Educational Resources Information Center

This paper focuses on developing a relatively simple method for analyzing web-logs. It also explores the challenges and benefits of web-log analysis. The study of student behavior on this site provides insights into website design and the effectiveness of this site in particular. Another benefit realized from the paper is the ease with which these

Klassen, Kenneth J.; Smith, Wayne

2004-01-01

257

Linear Discriminant Analysis and Discriminative Log-linear Modeling  

Microsoft Academic Search

We discuss the relationship between the discriminative training of Gaussian models and the maximum entropy framework for log-linear models. Observing that linear transforms leave the distributions resulting from the log- linear model unchanged, we derive a discriminative linear feature reduction technique from the maximum entropy ap- proach and compare it to the well-known linear discrimi- nant analysis. From experiments on

Daniel Keysers; Hermann Ney

2004-01-01

258

Detecting large-scale system problems by mining console logs  

Microsoft Academic Search

Surprisingly, console logs rarely help operators detect problems in large-scale datacenter services, for they of- ten consist of the voluminous intermixing of messages from many software components written by independent developers. We propose a general methodology to mine this rich source of information to automatically detect system runtime problems. We first parse console logs by combining source code analysis with

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

2009-01-01

259

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

260

Preprocessing and Mining Web Log Data for Web Personalization  

E-print Network

Preprocessing and Mining Web Log Data for Web Personalization M. Baglioni1 , U. Ferrara2 , A. Romei/26, 56017 S. Martino Ulmiano (PI) Italy ferrara@ksolutions.it Abstract. We describe the web usage mining behaviour of a web site users. The models are inferred from the access logs of a web server by means of data

Ruggieri, Salvatore

261

HazLog: Tool Support for Hazard Management  

Microsoft Academic Search

Industry is increasingly adopting software and system safety standards that mandate the use of hazard logs in the develop- ment and operation of safety critical systems. Hazard logs are used to record and track the results of hazard analysis and risk assessment throughout the lifecycle of the system. Even rela- tively simple systems give rise to large amounts of information

Christian Hamoy; David Hemer; Peter A. Lindsay

2004-01-01

262

Alert Detection in System Logs Adam J. Oliner  

E-print Network

Alert Detection in System Logs Adam J. Oliner , Alex Aiken Stanford University Stanford, CA 94305 supercomputers: using logs representing over 746 million processor-hours, in which anomalous events called alerts those alerts. We formalize the alert detection task in these terms, describe how Nodeinfo uses

Aiken, Alex

263

A practical approach to the interpretation of cement bond logs  

SciTech Connect

The Cement Bond Log has been controversial since its inception. Despite its potential, it is possibly the most maligned logging service available to the industry. Effective zone isolation between permeable intervals in a well requires a cement sheath over an appreciable vertical interval. It is necessary for the annular cement sheath to provide an effective hydraulic seal in order to withstand subsequent completion and production operations. The oil industry has used wireline well logs to detect the presence or absence of cement behind pipe for more than twenty years. Users have attempted, not always successfully, to evaluate the effectiveness of cement bond to both pipe and formation, ostensibly, with Cement Bond Logs. Cement Bond Logs do not mislead. Poor interpretation habits mislead. Knowledge of the well completion and the inherent physical restraints placed upon the log measurements is needed in order to properly evaluate the log. The purpose here is to dispel some of the myths created by misguided interpretation practices. Examples of Cement Bond Logs which fall into this category are presented.

Bigelow, E.L.

1985-03-01

264

A practical approach to the interpretation of cement bond logs  

SciTech Connect

The cement bond log has been controversial since its inception. Despite its potential, it is possibly the most maligned logging service available to the industry. Effective zone isolation between permeable intervals in a well requires a cement sheath over an appreciable vertical interval. It is necessary for the annular cement sheath to provide an effective hydraulic seal to withstand subsequent completion and production operations. The oil industry has used wireline well logs to detect the presence or absence of cement behind pipe for more than 20 years. Users have attempted, not always successfully, to evaluate the effectiveness of cement bond to both pipe and formation with cement bond logs. Cement bond logs do not mislead. Poor interpretation habits mislead. Knowledge of the well completion and the inherent physical restraints placed on the log measurements is needed to evaluate the log properly. The purpose here is to dispel some of the myths created by misguided interpretation practices. Examples of cement bond logs that fall into this category are be presented.

Bigelow, E.L.

1985-07-01

265

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

266

Differentially Private Search Log Sanitization with Optimal Output Utility  

E-print Network

Web search logs contain extremely sensitive data, as evidenced by the recent AOL incident. However, storing and analyzing search logs can be very useful for many purposes (i.e. investigating human behavior). Thus, an important research question is how to privately sanitize search logs. Although several search log anonymization techniques have been proposed with concrete privacy models, the output utility of most techniques is merely evaluated but not necessarily maximized. Indeed, when applying any privacy standard to the search log anonymization, the optimal (maximum utility) output can be derived according to the inter-relation between privacy and utility. In this paper, we take a first step towards tackling this problem by formulating utility-maximizing optimization problems based on the rigorous privacy standard of differential privacy. Specifically, we utilize optimization models to maximize the output utility of the sanitization for different applications, while ensuring that the production process sati...

Hong, Yuan; Lu, Haibing; Wu, Mingrui

2011-01-01

267

Added values.  

PubMed

Values-based interviewing is an approach to recruitment that focuses on the job applicant's attitudes and behaviours and whether they are a good 'fit' for the organization.Used successfully by hospitals in the United States, the approach is being introduced to some NHS trusts. PMID:24734812

Trueland, Jennifer

268

Redeeming Value.  

ERIC Educational Resources Information Center

Presents an essay on organizational transformation and the way successful marketing transformations redeem a sense of value. Focuses on challenges faced by not-for-profit institutions, current changes in the library profession, and implications of the American Library Association's Goal 2000. A sidebar summarizes an interview with the director of

Whitwell, Stuart C. A.

1995-01-01

269

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

270

Estimating monthly streamflow values by cokriging  

USGS Publications Warehouse

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 value, estimation is improved by accounting for correlation. Concurrent and lag-one observations tend to screen the influence of other available observations. Three models of covariance structure in residual log-flow records are compared using cross-validation. Models differ in how much monthly variation they allow in covariance. Precision of estimation, reflected in mean squared error (MSE), proved to be insensitive to this choice. Cross-validation is suggested as a tool for choosing an inverse transformation when an initial nonlinear transformation is applied to flow values. ?? 1986 Plenum Publishing Corporation.

Solow, A.R.; Gorelick, S.M.

1986-01-01

271

Rendering log aesthetic curves via Runge-Kutta method  

NASA Astrophysics Data System (ADS)

Log Aesthetic Curves (LAC) are visually pleasing curves which has been developed using monotonic curvature profile. Hence, it can be easily implemented in product design environment, e.g, Rhino 3D CAD systems. LAC is generally represented in an integral form of its turning angle. Traditionally, Gaussian-Kronrod method has been used to render this curve which consumes less than one second for a given interval. Recently, Incomplete Gamma Function was proposed to represent LAC analytically which decreases the computation time up to 13 times. However, only certain value of shape parameters (denoted as ?) which dictates the types of curves generated for LAC, can be used to compute LAC. In this paper, the classical Runge-Kutta (RK4) method is proposed to evaluate LAC numerically to reduce the LAC computation time for arbitrary, ?. The preliminary result looks promising where the evaluation time is decreased tremendously. This paper also demonstrates the accuracy control of LAC by reducing the stepsize of RK4. The computation time and the accuracy for various ?, are also illustrated in the last section of this paper.

Gobithaasan, R. U.; Meng, T. Y.; Piah, A. R. M.; Miura, K. T.

2014-07-01

272

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

2011-06-01

273

Downhole Log Assessment of Gas Hydrate and Free-Gas Concentrations on Hydrate Ridge  

NASA Astrophysics Data System (ADS)

The downhole-logging program on ODP Leg 204 was designed to assess the occurrence and concentration of gas hydrates on Hydrate Ridge. Logging while drilling (LWD) tools were deployed at eight (Site 1244-1150) of the nine sites drilled on southern Hydrate Ridge. LWD tools measure in-situ formation properties with instruments located in the drill collars immediately above the drill bit. The LWD tools used during Leg 204 included the resistivity-at-the-bit (RAB-GVR) tool, the magnetic resonance while drilling (MRWD) tool, and the azimuthal density-neutron (VDN) tool. The downhole log inferred distribution of gas hydrate beneath Hydrate Ridge and the adjacent slope basin is heterogeneous, with downhole RAB images showing gas hydrate occupying fractures and occurring as a disseminated pore-filling material within flat lying stratigraphic units with thicknesses varying from several centimeters to as much as 10 m. It has been shown that it is possible to obtain gas-hydrate saturations (percent of pore space occupied by gas hydrate) by using the Archie relation to analyze the electrical resistivity of gas-hydrate-bearing sediments. In this study, the Archie relation was used with resistivity data from the GVR tool and porosity data from the VDN density tool to calculate water saturations at all eight LWD log sites on Hydrate Ridge. The Archie relation yielded water saturations ranging from low values near the crest of the ridge, of about 10% in Hole 1249A, to a more common value of about 90% along the flanks of the ridge. It is generally accepted that with the zone of gas hydrate stability, gas hydrate saturations (Sh) are the mathematical complement of Archie derived water saturations (Sw), with Sh=1-Sw. Thus, the Archie derived gas hydrate saturations at the crest of the ridge exceed 90%. It should be noted that the Archie relation cannot distinguish between the occurrence of free-gas and gas hydrate. But, density, neutron, and NMR log derived porosity data can be used to differentiate gas-hydrate from free-gas-bearing sediments. At Site 1249, the density and neutron log-derived porosities are generally higher than the core-derived porosities. However, the NMR porosities are lower than the core-derived porosities. The apparent increase in density and neutron log derived porosities can be attributed to the occurrence of gas hydrate, as can the apparent decrease in NMR porosities. The affect of gas hydrate on density and neutron-derived porosities is relatively small. But NMR porosities are more significantly affected by the presence of gas hydrate. Neutron porosity logs are also affected by the presence of free-gas (yielding apparent low porosity measurements), but the downhole neutron porosity logs did not reveal the presence of any free-gas above the depth of the BSR on Hydrate Ridge. However, the combined Archie and porosity log analysis did reveal the occurrence of free-gas below the BSR on Hydrate Ridge, with free-gas saturations exceeding 50% in the "Horizon A" turbidite sequence.

Collett, T. S.; Goldberg, D. S.; Janik, A.; Guerin, G.

2003-12-01

274

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

275

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

276

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

277

LogStore: Toward Energy-Proportional Storage Servers Wei Zheng Ana Paula Centeno Frederic Chong  

E-print Network

, lower energy consumption. Our evaluation with real I/O workloads shows that LogStore can decrease energy High speed Offered load LogStore Low speed Log is active here A B Figure 1: Main idea of LogStoreLogStore: Toward Energy-Proportional Storage Servers Wei Zheng Ana Paula Centeno Frederic Chong

Bianchini, Ricardo

278

Methane hydrate pore saturation evaluation from geophysical logging and pressure core analysis, at the first offshore production test site in the eastern Nankai Trough, Japan  

NASA Astrophysics Data System (ADS)

On March 2013, the first offshore production test form methane hydrate (MH) concentrated zone (MHCZ) was conducted by the Research Consortium for Methane Hydrate Resource Development in Japan (MH21) at the AT1 site located in the north-western slope of Daini-Atsumi Knoll in the eastern Nankai Trough, Japan. Before the production test, extensive geophysical logging and pressure coring using Hybrid Pressure Coring System were conducted in 2012 at monitoring well (AT1-MC) and coring well (AT1-C), in order to obtain basic information for the MH reservoir characterization. MH pore saturation (Sh) is one of the important basic parameters not only for reservoir characterization, but also the resource assessment. However, precise evaluation of Sh from geophysical logging is still challenging technical issue. The MHCZ confirmed by the geophysical logging at AT1-MC has a turbidite assemblage (from several tens of centimeters to a few meters) with 60 m of gross thickness; it is composed of lobe/sheet type sequences in the upper part, and relatively thick channel sand sequences in the lower part. In this study, the Sh evaluated from geophysical logging data were compared with those evaluated from pressure core analysis. Resistivity logs and nuclear magnetic resonance (NMR) log were used for the Sh evaluation by geophysical logging. Standard Archie equation was applied for Sh evaluation from resistivity log, while density magnetic resonance (DMR) method was used for Sh evaluation from NMR log. The Sh from pressure core samples were evaluated using the amount of dissociated gas volume, together with core sample bulk volume, measured porosity, net sand intervals, and assumed methane solubility in pore water. In the upper part of the MHCZ, Sh estimated from resistivity log showed distinct difference in value between sand and mud layers, compared to Sh from NMR log. Resistivity log has higher vertical resolution than NMR log, so it is favorable for these kinds of thin bed evaluation. In this part, 50 to 80% of Sh was observed in sandy layer, which showed fairly good agreement with core derived Sh. On the other hand, lower part of the MHCZ, Sh estimated from both resistivity and NMR log showed higher background value and relatively smoother curve than upper part. In this part, 50 to 80% of Sh was observed in sandy layer, which was also showed good agreement with core derived Sh. This study was conducted by the Research Consortium for Methane Hydrate Resource Development in Japan (MH21).

Fujii, T.; Suzuki, K.; Takayama, T.; Konno, Y.; Yoneda, J.; Egawa, K.; Ito, T.; Nagao, J.

2013-12-01

279

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

SciTech Connect

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 to retain.

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

1997-05-01

280

Impact of logging on a mangrove swamp in south Mexico: cost/benefit analysis.  

PubMed

Environmental changes caused by logging in a mangrove swamp were studied in Barra de Tecoanapa, Guerrero, Mexico. Original forest included Rhizophora mangle, Laguncularia racemosa, Avicennia germinans and halophytic vegetation, and produced wood (164.03 m3/ha) and organic matter (3.9 g/m2/day). A total of 3.5 tons of wood per year were harvested from this area. Later, an average of 2,555 kg of maize per planting cycle were obtained (market value of 88 USD). Succession when the area was abandoned included strictly facultative and glycophyte halophytes (16 families, Cyperaceae and Poaceae were the best represented). After logging, temperatures increased 13 degrees C in the soil and 11 degrees C in the air, whereas salinity reached 52 psu in the dry season. These modified soil color and sand content increased from 42.6 to 63.4%. Logging was deleterious to species, habitat, biogeochemical and biological cycles, organic matter production, seeds, young plants, genetic exchange conservation of soil and its fertility, coastal protection, and aesthetic value; 3,000 m2 had eroded as the river advanced towards the deforested area (the cost/benefit analysis showed a ratio of 246:1). There was long-term economic loss for the community and only 30% of the site has recovered after five years. PMID:11935907

Tovilla-Hernndez, C; Espino de la Lanza, G; Orihuela-Belmonte, D E

2001-06-01

281

21 CFR 211.182 - Equipment cleaning and use log.  

Code of Federal Regulations, 2011 CFR

...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Records and Reports 211.182 Equipment cleaning and use log. A written record of major...

2011-04-01

282

21 CFR 211.182 - Equipment cleaning and use log.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Records and Reports 211.182 Equipment cleaning and use log. A written record of major...

2010-04-01

283

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

284

5. VIEW OF SITE, AREA B; LOG BUILDING AND BUNKHOUSE ...  

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

5. VIEW OF SITE, AREA B; LOG BUILDING AND BUNKHOUSE (Features 9 and 10) AT FAR LEFT AND HOUSE (Feature 13) AT CENTER (n.d.) - Gold Dust Mine, Mill & Camp Complex, Wards Gulch, Salmon, Lemhi County, ID

285

Report Exec Administrator Clery Act Public Crime Log  

E-print Network

Report Exec Administrator Clery Act Public Crime Log From 9/1/2013 To 9/30/2013 Incident Type that there was a female subject vomiting in the parking lot; juvenile subject was released to her parent. Int. Ref

Boyce, Richard L.

286

Log-periodic behavior of a hierarchical failure model with ...  

E-print Network

an excellent ?t to a. log-periodic increase in the Benioff strain release. ... is transferred to a neighboring element; if two adjacent elements fail, stress is transferred to two ..... TABLE I. Realization of failure 115111565 536 point simulation: Three...

287

47 CFR 73.877 - Station logs for LPFM stations.  

Code of Federal Regulations, 2012 CFR

...Section 73.877 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Low Power FM Broadcast Stations (LPFM) 73.877 Station logs for LPFM stations. The...

2012-10-01

288

47 CFR 73.877 - Station logs for LPFM stations.  

Code of Federal Regulations, 2011 CFR

...Section 73.877 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Low Power FM Broadcast Stations (LPFM) 73.877 Station logs for LPFM stations. The...

2011-10-01

289

47 CFR 73.877 - Station logs for LPFM stations.  

Code of Federal Regulations, 2013 CFR

...Section 73.877 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Low Power FM Broadcast Stations (LPFM) 73.877 Station logs for LPFM stations. The...

2013-10-01

290

47 CFR 73.877 - Station logs for LPFM stations.  

Code of Federal Regulations, 2010 CFR

...Section 73.877 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Low Power FM Broadcast Stations (LPFM) 73.877 Station logs for LPFM stations. The...

2010-10-01

291

16. VIEW OF UNIDENTIFIED MEN STANDING ON LOG BRIDGE ALONG ...  

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

16. VIEW OF UNIDENTIFIED MEN STANDING ON LOG BRIDGE ALONG UNIDENTIFIED SECTION OF GOAT TRAIL MINING ROAD - Goat Trail Mining Road, Highway 20, 1.5 miles North of Newhalem, Newhalem, Whatcom County, WA

292

14 CFR 60.20 - Logging FSTD discrepancies.  

Code of Federal Regulations, 2010 CFR

...20 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN FLIGHT SIMULATION TRAINING DEVICE INITIAL AND CONTINUING QUALIFICATION AND USE 60.20 Logging FSTD discrepancies. Each...

2010-01-01

293

13. Plan drawing: North Dakota State Highway Department Log ...  

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

13. Plan drawing: North Dakota State Highway Department - Log of test borings - Lost Bridge, Spanning Little Missouri River, twenty-three miles north of Killdeer, ND, on State Highway No. 22, Killdeer, Dunn County, ND

294

Partnership Logging Accidents Cornelis de Hoop, LA Forest Products Lab  

E-print Network

Partnership Logging Accidents · by · Cornelis de Hoop, LA Forest Products Lab · Albert Lefort Agreement · 1998 & 1999 Accident Reports · 25 injuries reported · 185 loggers signed up · 8 deaths 1999

295

3. VIEW OF TUNNEL INTAKE, WITH LOG TRASH RACK, LOOKING ...  

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

3. VIEW OF TUNNEL INTAKE, WITH LOG TRASH RACK, LOOKING SOUTH - High Mountain Dams in Upalco Unit, Farmers Lake Tunnel, Ashley National Forest, 5.7 miles North of Swift Creek Campground, Mountain Home, Duchesne County, UT

296

15. Detail of log cribbing on southeast side of Pentagon ...  

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

15. Detail of log cribbing on southeast side of Pentagon 1 (note stone in center). View to northwest. - Pentagon Site, Pentagon 1, West of Barry's Landing off Highway 37, Fort Smith, Big Horn County, MT

297

11. Detail of log cribbing on north side of Pentagon ...  

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

11. Detail of log cribbing on north side of Pentagon 1, (note stone in left foreground). View to south. - Pentagon Site, Pentagon 1, West of Barry's Landing off Highway 37, Fort Smith, Big Horn County, MT

298

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

299

2. SOUTHWEST CORNER DETAIL, SHOWING LOG CONSTRUCTION AND DIAGONAL STONE ...  

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

2. SOUTHWEST CORNER DETAIL, SHOWING LOG CONSTRUCTION AND DIAGONAL STONE PATTERN IN CHINKING - Charles Wollerton House, Valley Creek & Sunset Hollow Roads vicinity (East Bradford Township), Downingtown, Chester County, PA

300

14 CFR 60.20 - Logging FSTD discrepancies.  

Code of Federal Regulations, 2011 CFR

...20 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN FLIGHT SIMULATION TRAINING DEVICE INITIAL AND CONTINUING QUALIFICATION AND USE 60.20 Logging FSTD discrepancies. Each...

2011-01-01

301

14 CFR 60.20 - Logging FSTD discrepancies.  

...20 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN FLIGHT SIMULATION TRAINING DEVICE INITIAL AND CONTINUING QUALIFICATION AND USE 60.20 Logging FSTD discrepancies. Each...

2014-01-01

302

14 CFR 60.20 - Logging FSTD discrepancies.  

Code of Federal Regulations, 2012 CFR

...20 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN FLIGHT SIMULATION TRAINING DEVICE INITIAL AND CONTINUING QUALIFICATION AND USE 60.20 Logging FSTD discrepancies. Each...

2012-01-01

303

14 CFR 60.20 - Logging FSTD discrepancies.  

Code of Federal Regulations, 2013 CFR

...20 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN FLIGHT SIMULATION TRAINING DEVICE INITIAL AND CONTINUING QUALIFICATION AND USE 60.20 Logging FSTD discrepancies. Each...

2013-01-01

304

Log-domain circuit models of chemical reactions  

E-print Network

We exploit the detailed similarities between electronics and chemistry to develop efficient, scalable bipolar or subthreshold log-domain circuits that are dynamically equivalent to networks of chemical reactions. Our ...

Mandal, Soumyajit

305

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

306

Biosorption of phenanthrene by pure algae and field-collected planktons and their fractions.  

PubMed

The biosorption isotherms for phenanthrene (Phen) by cultured algae, field-collected plankton, and market algae samples (OSs) and their fractions (lipid-LP, lipid free carbon-LF, alkaline nonhydrolyzable carbon-ANHC, and acid nonhydrolyzable carbon-NHC) were established. All the biosorption isotherms are well fitted by the Freundlich model. The biosorption isotherms for the ANHC and NHC fractions are nonlinear and for the other fractions are linear. It was found that the NHC fractions are chemically and structurally different from other fractions by using elemental analysis and Fourier transformed infrared spectroscopy (FTIR), consisting mainly of aliphatic polymethylene carbon. The average KOC values for Phen at Ce=0.005Sw are 107062768mLg(-1) and 9584355817mLg(-1) for the bulk market algal samples and their NHC isolates, respectively. As the NHC fraction for Porphyra contains higher polymethylene carbon than that for Seaweed or Spirulina, it exhibits higher biosorption capacity. Moreover, the logKOC values are significantly higher for the field-collected samples than for the market algae and cultured algae samples. The multivariate correlation shows that the logKOC values are positively related to the LP contents, and negatively to the C/N ratios for the original algal samples. Furthermore, the logKOC values are negatively related to the polarity indices (O/C and O+N/C) for the original samples and their fractions excluding LP fractions. These observations help to understand the role of polarity, LP and NHC fractions, and aliphatic structures in the biosorption of Phen, which requires more attention in the examination of sorption processes in the natural environment. PMID:23714149

Zhang, Dainan; Ran, Chenyang; Yang, Yu; Ran, Yong

2013-09-01

307

Calculation of sensitivity coefficients for a neutron well logging tool  

E-print Network

in this research. TWODANT, a, two-dimensional computer code was used to estimate the neutron flux and other neutronic information concerning the logging tool's response, then a straightforward direct method based on the definition of sensitivity wss used..., and acoustic techniques. Neutron logging is one of the newer methods based on nuclear radiation and it has been increasingly applied over the last fifteen years using both steady ? state and pulsed neutron sources of various types. (Hearst et al. , 1985...

Chen, Chien-Hsiang

2012-06-07

308

Log-periodic Critical Amplitudes: A Perturbative Approach  

NASA Astrophysics Data System (ADS)

Log-periodic amplitudes appear in the critical behavior of a large class of systems, in particular when a discrete scale invariance is present. Here we show how to compute these critical amplitudes perturbatively when they originate from a renormalization map which is close to a monomial. In this case, the log-periodic amplitudes of the subdominant corrections to the leading critical behavior can also be calculated.

Derrida, Bernard; Giacomin, Giambattista

2013-06-01

309

A microstrip-fed log-periodic slot array  

Microsoft Academic Search

Log-periodic slot arrays offer the potential for broadband performance in addition to endfire patterns whose linear polarization is perpendicular to the plane of the array. Effective methods of analyzing such a class of antennas are lacking. In this paper we present a printed microstrip-fed log-periodic slot array featuring a common cavity for all slots. Slot fields and equivalent slot series

J. J. Moncada; T. L. Anderson

1994-01-01

310

Asymmetry phenomenon of log-periodic dipole antennas  

Microsoft Academic Search

The existence of asymmetric resonant modes on standard log-periodic dipole antennas is established experimentally. These modes are characterized by sharply-resonant side radiation sometimes accompanied by reduction in front-lobe gain. The resonances occur at frequencies whose relationship is approximately log-periodic. In a single antenna the resonant modes are excited by any structural asymmetry, while in anE-plane array each individual antenna excites

K. Balmain; J. Nkeng

1976-01-01

311

Fossil Big Bang Turbulence log k , 1/m  

E-print Network

Fossil Big Bang Turbulence 35 log k , 1/m -15 3127-19-23 k2T +1/3 k2T 1/2 = l l+1 Cl +1/6 log k , 1/m inflation Planck scale BOOMERANG t =0 t = 10-35 s LH = ct 10-27 m QGD epoch QGD fossil LB LP LH is irreversible, triggering formation of quantum- gravitational-turbulence and a Big Bang Universe. Entropy

Wang, Deli

312

Field comparison of conventional and new technology temperature logging systems  

Microsoft Academic Search

Field tests were conducted in the summer of 1995 on four state-of-the-art temperature logging systems: an analog, electric-line, system; two pressure and temperature recording memory tools (in-hole computer systems); and a Distributed optical fibre Temperature Sensing (DTS) system. The tools produced accurate, detailed, temperature versus depth and temperature gradient versus depth logs at depths to 2 km and temperatures to

Ken W. Wisian; David D. Blackwell; Stefano Bellani; Joe A. Henfling; Randy A. Normann; Peter C. Lysne; Andrea Frster; Jrg Schrtter

1998-01-01

313

Application of gas-filled detectors for well logging  

NASA Astrophysics Data System (ADS)

The advantages of using gas-filled multiwire proportional chambers (MWPC) for well logging are discussed. In particular, applicability of the MWPC in casing quality control and cement bond logging is described. It is shown that spatial distribution measurement of scattered gamma rays can provide information about the material and presence of the defects. The results of computations performed with GEANT4 are in the reasonable agreement with the experimental data.

Korkin, R.; Baru, S. E.; Porosev, V. V.; Savinov, G. A.

2008-06-01

314

Geophysical logs of selected wells in Eastern Washington  

SciTech Connect

This report consists of geophysical well logs compiled during studies of the geohydrology and low temperature geothermal resources of eastern Washington. The geophysical logs are divided into two groups. Part A consists of wells concentrated in the Moses Lake-Ritzville-Connell area. Results of the geohydrologic study are discussed in Widness (1983, 1984). Part B consists of wells outside of the Moses Lake-Ritzville-Connell study area.

Stoffel, K.L.; Widness, S.

1983-12-01

315

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

316

An acoustic-logging transmission-network model.  

PubMed

The acoustic logging process can be described as a signal transmission system with a corresponding transmission network model. This model gives the relations between driving-voltage signal, the electrical-acoustic conversion at the source, acoustic properties of the propagation media (borehole fluid and formation around borehole), the pressure response in the borehole, the acoustic-electrical conversion at the receiver and recorded logging signal. PMID:12051435

Fa, Lin; Castagna, John P; Hovem, Jens M; Dong, Daqun

2002-05-01

317

Reference change values.  

PubMed

Reference change values (RCV) provide objective tools for assessment of the significance of differences in serial results from an individual. The concept is simple and the calculation easy, since all laboratories know their analytical imprecision (CV(A)) and estimates of within-subject biological variation (CV(I)) are available for a large number of quantities. Generally, CV(I) are constant over time, geography, methodology and in health and chronic stable disease. The formula is RCV=2(1/2) Z (CV(A)(2) + CV(I)(2))(1/2), where Z is the number of standard deviations appropriate to the probability. Correct interpretation of the semantics describing the clinical use of RCV is vital for selection of the Z-score. Many quantities of clinically importance exist for which good estimates of RCV are unavailable. Derivation of CV(I) may be difficult for such quantities: flair and imagination are required in selecting populations with chronic but stable disease on whom CV(I) can be determined. RCV can be used for delta-checking and auto-verification and laboratory information management systems (LIMS) can be adapted to do this. Recently, log-normal transformation to obtain unidirectional RCV has been used. Gaps in knowledge of RCV still require filling since the need for measures of change is clearly expressed in guidelines. PMID:21958344

Fraser, Callum G

2012-05-01

318

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. PMID:22690019

Boos, Dennis D.; Stefanski, Leonard A.

2011-01-01

319

14 CFR 91.1443 - CAMP: Airworthiness release or aircraft maintenance log entry.  

Code of Federal Regulations, 2010 CFR

...Airworthiness release or aircraft maintenance log entry. 91.1443...Airworthiness release or aircraft maintenance log entry. (a) No program...appropriate entry in the aircraft maintenance log. (b) The...

2010-01-01

320

14 CFR 91.1443 - CAMP: Airworthiness release or aircraft maintenance log entry.  

Code of Federal Regulations, 2012 CFR

...Airworthiness release or aircraft maintenance log entry. 91.1443...Airworthiness release or aircraft maintenance log entry. (a) No program...appropriate entry in the aircraft maintenance log. (b) The...

2012-01-01

321

14 CFR 135.443 - Airworthiness release or aircraft maintenance log entry.  

Code of Federal Regulations, 2013 CFR

... Airworthiness release or aircraft maintenance log entry. 135.443... Airworthiness release or aircraft maintenance log entry. (a) No certificate...appropriate entry in the aircraft maintenance log. (b) The...

2013-01-01

322

14 CFR 91.1443 - CAMP: Airworthiness release or aircraft maintenance log entry.  

Code of Federal Regulations, 2013 CFR

...Airworthiness release or aircraft maintenance log entry. 91.1443...Airworthiness release or aircraft maintenance log entry. (a) No program...appropriate entry in the aircraft maintenance log. (b) The...

2013-01-01

323

14 CFR 135.443 - Airworthiness release or aircraft maintenance log entry.  

Code of Federal Regulations, 2011 CFR

... Airworthiness release or aircraft maintenance log entry. 135.443... Airworthiness release or aircraft maintenance log entry. (a) No certificate...appropriate entry in the aircraft maintenance log. (b) The...

2011-01-01

324

14 CFR 91.1443 - CAMP: Airworthiness release or aircraft maintenance log entry.  

...Airworthiness release or aircraft maintenance log entry. 91.1443...Airworthiness release or aircraft maintenance log entry. (a) No program...appropriate entry in the aircraft maintenance log. (b) The...

2014-01-01

325

14 CFR 91.1443 - CAMP: Airworthiness release or aircraft maintenance log entry.  

Code of Federal Regulations, 2011 CFR

...Airworthiness release or aircraft maintenance log entry. 91.1443...Airworthiness release or aircraft maintenance log entry. (a) No program...appropriate entry in the aircraft maintenance log. (b) The...

2011-01-01

326

14 CFR 135.443 - Airworthiness release or aircraft maintenance log entry.  

Code of Federal Regulations, 2012 CFR

... Airworthiness release or aircraft maintenance log entry. 135.443... Airworthiness release or aircraft maintenance log entry. (a) No certificate...appropriate entry in the aircraft maintenance log. (b) The...

2012-01-01

327

Valuing vaccination  

PubMed Central

Vaccination has led to remarkable health gains over the last century. However, large coverage gaps remain, which will require significant financial resources and political will to address. In recent years, a compelling line of inquiry has established the economic benefits of health, at both the individual and aggregate levels. Most existing economic evaluations of particular health interventions fail to account for this new research, leading to potentially sizable undervaluation of those interventions. In line with this new research, we set forth a framework for conceptualizing the full benefits of vaccination, including avoided medical care costs, outcome-related productivity gains, behavior-related productivity gains, community health externalities, community economic externalities, and the value of risk reduction and pure health gains. We also review literature highlighting the magnitude of these sources of benefit for different vaccinations. Finally, we outline the steps that need to be taken to implement a broad-approach economic evaluation and discuss the implications of this work for research, policy, and resource allocation for vaccine development and delivery. PMID:25136129

Barnighausen, Till; Bloom, David E.; Cafiero-Fonseca, Elizabeth T.; O'Brien, Jennifer Carroll

2014-01-01

328

40 CFR 82.178 - Information required to be submitted.  

Code of Federal Regulations, 2013 CFR

...not limited to: Molecular weight; physical state; melting point; boiling point; density; taste and/or odor threshold; solubility; partition coefficients (Log Kow , Log Koc ); atmospheric lifetime and vapor pressure. (3) Substitute...

2013-07-01

329

40 CFR 82.178 - Information required to be submitted.  

Code of Federal Regulations, 2012 CFR

...not limited to: Molecular weight; physical state; melting point; boiling point; density; taste and/or odor threshold; solubility; partition coefficients (Log Kow , Log Koc ); atmospheric lifetime and vapor pressure. (3) Substitute...

2012-07-01

330

Log-optimal portfolio models with risk control of VaR and CVaR using genetic algorithms  

Microsoft Academic Search

Value-at-risk (VaR) and conditional value-at-risk (CVaR) have become two very popular measures of market risk during the last decade. Log-optimal portfolio problem with risk control of VaR and CVaR is put forward firstly. Then, we propose the portfolio models with VaR and CVaR and prove the existence and uniqueness of the optimal solutions of these two models. We provide a

Sen Qin

2009-01-01

331

Annual Logging Symposium, June 3-6, 2007 JOINT INVERSION OF DENSITY AND RESISTIVITY LOGS FOR THE  

E-print Network

, Robert Terry, BP Copyright 2007, held jointly by the Society of Petrophysicists and Well Log Analysts of in-place hydrocarbon reserves. To gain better understanding of measurement behavior in interbedded

Torres-Verdín, Carlos

332

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 dcollement zone was

Mara Jos Jurado; Beln Alonso

333

A comprehensive approach to studies of porous media (rocks) using a laboratory spectrometer and logging tool with similar operating characteristics.  

PubMed

The value of NMR spectrometry as a way to understand the porosity and permeability of rocks is well documented. Other more esoteric parameters, such as restrictive diffusion, grain size distribution, and fluid viscosities have received less notice but are also available from the NMR measurements as laboratory studies have shown. With the introduction of gradient field spin-echo NMR well logging, all of these parameters become available in a routine way. To accomplish the goal of having a well log that systematically provides this complete array of NMR answers requires consideration of the measurement principles that can be applied. Magnetic field strength and the relative merits of gradient versus homogeneous magnetic fields methods, as well as the limitations presented by the well bore and wireline systems are a few examples of the factors that must be considered. As important, to the end user, is being provided a definitive link between the well logging response and laboratory measurements on rock samples that prove the meaning of the log. This is ideally accomplished when the laboratory measurements are attained using an apparatus that has the same operating characteristics as the log. For most well logging systems this is seldom accomplished to the degree desired, but it is readily attainable with NMR technologies. The consideration of these factors and the features and benefits of having such a capability are the focus of this paper. The technical attributes of such a comprehensive system, the Numar Corporation's "MRIL" and "CoreSpec1000", plus actual examples of laboratory and well bore data are provided to show the value of such an approach. PMID:8170320

Taicher, Z; Coates, G; Gitartz, Y; Berman, L

1994-01-01

334

Carbon emissions from tropical forest degradation caused by logging  

NASA Astrophysics Data System (ADS)

The focus of land-use related efforts in developing countries to reduce carbon emissions has been on slowing deforestation, yet international agreements are to reduce emissions from both deforestation and forest degradation (REDD). The second D is poorly understood and accounted for a number of technical and policy reasons. Here we introduce a complete accounting method for estimating emission factors from selective timber harvesting, a substantial form of forest degradation in many tropical developing countries. The method accounts separately for emissions from the extracted log, from incidental damage to the surrounding forest, and from logging infrastructure, and emissions are expressed as units of carbon per cubic meter of timber extracted to allow for simple application to timber harvesting statistics. We applied the method in six tropical countries (Belize, Bolivia, Brazil, Guyana, Indonesia, and Republic of Congo), resulting in total emission factors of 0.99-2.33 Mg C m-3. In all cases, emissions were dominated by damage to surrounding vegetation and the infrastructure rather than the logs themselves, and total emissions represented about 3-15% of the biomass carbon stocks of the associated unlogged forests. We then combined the emission factors with country level logging statistics for nine key timber producing countries represented by our study areas to gain an understanding of the order of magnitude of emissions from degradation compared to those recently reported for deforestation in the same countries. For the nine countries included, emissions from logging were on average equivalent to about 12% of those from deforestation. For those nine countries with relatively low emissions from deforestation, emissions from logging were equivalent to half or more of those from deforestation, whereas for those countries with the highest emissions from deforestation, emissions from logging were equivalent to <10% of those from deforestation. Understanding how to account emissions and the magnitude of each emissions source resulting from tropical timber harvesting practices helps identify where there are opportunities to reduce emissions from the second D in REDD.

Pearson, Timothy R. H.; Brown, Sandra; Casarim, Felipe M.

2014-03-01

335

Imprints of log-periodic self-similarity in the stock market  

E-print Network

Detailed analysis of the log-periodic structures as precursors of the financial crashes is presented. The study is mainly based on the German Stock Index (DAX) variation over the 1998 period which includes both, a spectacular boom and a large decline, in magnitude only comparable to the so-called Black Monday of October 1987. The present example provides further arguments in favour of a discrete scale-invariance governing the dynamics of the stock market. A related clear log-periodic structure prior to the crash and consistent with its onset extends over the period of a few months. Furthermore, on smaller time-scales the data seems to indicate the appearance of analogous log-periodic oscillations as precursors of the smaller, intermediate decreases. Even the frequencies of such oscillations are similar on various levels of resolution. The related value $\\lambda \\approx 2$ of preferred scaling ratios is amazingly consistent with those found for a wide variety of other complex systems. Similar analysis of the major American indices between September 1998 and February 1999 also provides some evidence supporting this concept but, at the same time, illustrates a possible splitting of the dynamics that a large market may experience.

S. Drozdz; F. Ruf; J. Speth; M. Wojcik

1999-01-05

336

Use of electric logs to estimate water quality of pre-tertiary aquifers  

SciTech Connect

Electric logs provide a means of estimating groundwater quality in areas where water analyses are not available. Most of the methods for interpreting these logs have been developed for the petroleum industry and are most reliable in saline aquifers (concentration of dissolved solids as sodium chloride greater than about 50,000 mg/l). The resistivity-porosity and spontaneous-potential methods were evaluated to determine if they could be applied to identify zones of fresh water (concentration of dissolved solids as sodium chloride less than 1,000 mg/l) in three potential aquifers in central Wyoming. The potential aquifers have different lithologies--sandstone, clayey sandstone, and carbonate. The two methods generally were reliable predictors of water quality in the sandstone and carbonate potential aquifers. In the clayey sandstone potential aquifer, predictions of the dissolved-solids concentration using the two methods differed by more than an order of magnitude in several cases. When the resistivity values are corrected for the presence of clay and shale as identified on a natural gamma log, the agreement between the results of the two methods improved by an average of 58%.

Lindner-Lunsford, J.B. [Geological Survey, Commerce City, CO (United States). Water Resources Div.; Bruce, B.W. [Geological Survey, Lakewood, CO (United States). Water Resources Div.

1995-07-01

337

Four Decades of Forest Persistence, Clearance and Logging on Borneo  

PubMed Central

The native forests of Borneo have been impacted by selective logging, fire, and conversion to plantations at unprecedented scales since industrial-scale extractive industries began in the early 1970s. There is no island-wide documentation of forest clearance or logging since the 1970s. This creates an information gap for conservation planning, especially with regard to selectively logged forests that maintain high conservation potential. Analysing LANDSAT images, we estimate that 75.7% (558,060 km2) of Borneo's area (737,188 km2) was forested around 1973. Based upon a forest cover map for 2010 derived using ALOS-PALSAR and visually reviewing LANDSAT images, we estimate that the 1973 forest area had declined by 168,493 km2 (30.2%) in 2010. The highest losses were recorded in Sabah and Kalimantan with 39.5% and 30.7% of their total forest area in 1973 becoming non-forest in 2010, and the lowest in Brunei and Sarawak (8.4%, and 23.1%). We estimate that the combined area planted in industrial oil palm and timber plantations in 2010 was 75,480 km2, representing 10% of Borneo. We mapped 271,819 km of primary logging roads that were created between 1973 and 2010. The greatest density of logging roads was found in Sarawak, at 0.89 km km?2, and the lowest density in Brunei, at 0.18 km km?2. Analyzing MODIS-based tree cover maps, we estimate that logging operated within 700 m of primary logging roads. Using this distance, we estimate that 266,257 km2 of 1973 forest cover has been logged. With 389,566 km2 (52.8%) of the island remaining forested, of which 209,649 km2 remains intact. There is still hope for biodiversity conservation in Borneo. Protecting logged forests from fire and conversion to plantations is an urgent priority for reducing rates of deforestation in Borneo. PMID:25029192

Gaveau, David L. A.; Sloan, Sean; Molidena, Elis; Yaen, Husna; Sheil, Doug; Abram, Nicola K.; Ancrenaz, Marc; Nasi, Robert; Quinones, Marcela; Wielaard, Niels; Meijaard, Erik

2014-01-01

338

Log-Derived evaluation of shaly sandstone reservoirs  

SciTech Connect

Significant natural gas resources are known to exist in the United States in tight, low-permeability sandstones that cover a prospective area of 1,000,000 mi/sup 2/ (2,590,000 km/sup 2/). Characterization and reliable estimation of their production potential based on well logs are important although difficult task. Proper evaluation of low permeability sands based on conventional log-interpretation techniques is frequently inadequate. Furthermore, while empirical rules of thumb assist in the evaluation of localized conditions, they only provide guidelines. Recent developments in quantitative log-analysis techniques incorporate natural-gamma-ray spectral data and application of the Waxman-Smits model for detailed reservoir description. Quantitative correlations of cation exchange capacity (CEC), water salinity, porosity, and conductivity of water- and hydrocarbon-bearing shaly sand reservoirs are based on resistivity, density, neutron and natural-gamma-ray spectral data. These correlations provide important information about clay volume, reservoir porosities (total, effective) and fluid-saturation distribution (total, effective), type of clay minerals (smectite, illite, chlorite/kaolinite), their distribution in the reservoir (dispersed, laminated, structural), and log-derived indicators of potential formation damage. Field experiences are reviewed for logging and evaluating tight formations in south Texas; the Jurassic Cotton Valley trend in east Texas, Louisiana, and Arkansas; and the Tertiary Fort Union and Cretaceous Mesaverde Formations of the Piceance basin in Colorado.

Fertl, W.H.

1984-04-01

339

Thermal conductivity from core and well log data  

NASA Astrophysics Data System (ADS)

A number of attempts have been made to determine thermal conductivity from well log data, including direct empirical relationships between measured properties and more complex models based on mixing laws. The latter require interpretation of well log data in terms of lithology and porosity prior to thermal conductivity estimation. While the second approach is more universally applicable there is general agreement that every geologic setting needs calibration of well log data with core measurements. We present data and interpretations from the German Western Molasse Basin, an Alpine foreland basin. Cores were obtained from a geothermal well nearly continuously at depths from 550 - 800 m. The drilled sequence consists of typical Molasse sediments: sand- to siltstones with various amounts of calcareous components and clays. Especially clay makes the acquisition and interpretation of measurements a challenging task. A total of 170 samples was taken from the borehole. We measured thermal conductivity, sonic velocity, and bulk density in the laboratory on dry and saturated samples. A number of logs were obtained in the same borehole. We use these two data sets to review the relationships between the laboratory and field measurements for different models. Additionally, heat capacity was measured on selected samples. Using the heat capacity and density we calculate a thermal diffusivity log. This parameter and its variability is important for transient heat diffusion problems.

Hartmann, A.; Rath, V.; Clauser, C.

2003-04-01

340

Hyporheic exchange due to channel-spanning logs  

NASA Astrophysics Data System (ADS)

The flow of river water around large woody debris (LWD) creates pressure gradients along the riverbed that drive a large zone of river-groundwater mixing, or hyporheic exchange. Flume experiments and numerical simulations show that river water downwells into the riverbed upstream of a channel-spanning log and upwells downstream. Exchange rates are greatest near the log and decay exponentially with distance upstream and downstream. We developed equations for bed pressure profiles and hyporheic exchange rates in the vicinity of a channel-spanning log that can be used to evaluate the impact of LWD removal or reintroduction on hyporheic mixing. The magnitude of pressure disturbance along the bed (and thus hyporheic exchange) increases with the fraction of channel depth blocked by the log and channel Froude number. Exchange rates are relatively insensitive to relative depth of the log (gap ratio). At natural densities, LWD in lowland streams drives reach-averaged hyporheic exchange rates similar to a ripple-covered bed. However, the length scales and residence times of hyporheic exchange due to LWD are greater. By removing LWD from streams, humans have altered patterns and rates of hyporheic exchange, which influence habitat distribution and quality for invertebrates and fish.

Sawyer, Audrey H.; Bayani Cardenas, M.; Buttles, Jim

2011-08-01

341

Application of the spread-spectrum technique in well logging  

SciTech Connect

This paper presents the novel concept of employing the noise insensitive spread-spectrum technique in well logging. The proposed design of a spread-spectrum device improves the performance of well logging tools, particularly within highly noisy environments. The heart of the device is a shift register which generates a pseudorandom binary code sequence. A coder is connected to the transmitter and codes the probing signal by utilizing the pseudorandom sequence. A decoder is connected to the receiver and correlates the return signal to the same sequence, which is used as a sliding reference. Shifts as small as a fraction of a bit are unambiguously resolvable, and distance resolution of the order of micrometers is achievable. Spread-spectrum well logging tools can operate even with coded signal-to-noise ratio below zero-dB. The spread-spectrum device can be interfaced with any available wave transmitting logging tool. However, tools employing acoustic waves are favorable because the acoustic wave propagation velocity is low and allows the use of inexpensive electronics. The problems associated with high temperatures which are commonly encountered In geothermal reservoirs are bypassed, since the spread-spectrum device can be located either inside the well logging tool or together with the supporting electronics on the surface.

Chrysikopoulos, Constantinos V.; Dadakarides, Simos D.

1988-01-01

342

A decade of change in the saproxylic beetle fauna of eucalypt logs in the Warra long-term log-decay experiment, Tasmania. 2. Log-size effects, succession, and the functional significance of rare species  

Microsoft Academic Search

The first decade of sequential and cyclical sampling of the saproxylic beetles of twelve freshly felled Eucalyptus obliqua logs at Warra, Tasmania has allowed comparisons between larger-diameter mature and smaller-diameter regrowth log-classes\\u000a and between successive sampling cycles and years; and consideration of the interplay between these two aspects. The two log-classes\\u000a support different assemblages, with the mature log-class hosting consistently

Simon J. Grove; Lynette Forster

2011-01-01

343

Computer method to detect and correct cycle skipping on sonic logs  

SciTech Connect

A simple but effective computer method has been developed to detect cycle skipping on sonic logs and to replace cycle skips with estimates of correct traveltimes. The method can be used to correct observed traveltime pairs from the transmitter to both receivers. The basis of the method is the linearity of a plot of theoretical traveltime from the transmitter to the first receiver versus theoretical traveltime from the transmitter to the second receiver. Theoretical traveltime pairs are calculated assuming that the sonic logging tool is centered in the borehole, that the borehole diameter is constant, that the borehole fluid velocity is constant, and that the formation is homogeneous. The plot is linear for the full range of possible formation-rock velocity. Plots of observed traveltime pairs from a sonic logging tool are also linear but have a large degree of scatter due to borehole rugosity, sharp boundaries exhibiting large velocity contrasts, and system measurement uncertainties. However, this scatter can be reduced to a level that is less than scatter due to cycle skipping, so that cycle skips may be detected and discarded or replaced with estimated values of traveltime. Advantages of the method are that it can be applied in real time, that it can be used with data collected by existing tools, that it only affects data that exhibit cycle skipping and leaves other data unchanged, and that a correction trace can be generated which shows where cycle skipping occurs and the amount of correction applied. The method has been successfully tested on sonic log data taken in two holes drilled at the Nevada Test Site, Nye County, Nevada.

Muller, D.C.

1985-06-17

344

Solute transport in three-dimensional heterogeneous media with a Gaussian covariance of log hydraulic conductivity  

NASA Astrophysics Data System (ADS)

The analytical solutions for the velocity covariance, uij one particle displacement covariance Xij, and the macrodispersivity tensor ?ij defined as (0.5/?)(dXij/dt), were derived in three-dimensional heterogeneous media. A Gaussian covariance function (GCF) of logarithmic hydraulic conductivity, log K, was used, assuming uniform mean flow and first-order approximation in log-conductivity variance, where ? is the magnitude of the mean flow velocity ?. Based on these solutions, the time-dependent ensemble averages of the second spatial moments, Zij ? - Aij?0) = Xij - Rij and the effective dispersivity tensor ?ij defined as (0.5/?)(d/dt, were evaluated for a finite line source either normal or parallel to ?, where Aij(0) is the initial value of the second spatial moment of a plume, Aij and Rij is the plume centroid covariance. The results obtained in this study were compared with previous results for an exponential covariance function (ECF). It was found that in a stationary log K field the spreading of a solute plume depends not only on the variance and integral scale of the log K field but also on the shape of its covariance function. The more strongly correlated the hydraulic conductivities at short separation distances are, the faster Zii and ?ii grow at early time. Also, the earlier that ?ii approaches its asymptote or peak, and the higher the peak is, the larger the negative transverse dispersivity. More importantly, the ergodic limits for GCF are reached faster than those for ECF, as the initial size of a plume increases. The ergodic limit X11 for GCF is slightly larger than that for ECF, but X22 and X33 are significantly smaller than those for ECF even though the asymptotic ?ii for GCF is the same with that for ECF.

Zhang, You-Kuan; Federico, Vittorio Di

1998-08-01

345

Assessment of gas hydrate concentrations (saturations) with downhole electrical resistivity logs on Hydrate Ridge  

NASA Astrophysics Data System (ADS)

The downhole logging program on Ocean Drilling Program (ODP) Leg 204 was designed to obtain the data needed to assess the occurrence and concentration of gas hydrates beneath Hydrate Ridge off the northwest coast of the United States. During Leg 204, logging-while-drilling (LWD) tools were deployed at eight of the nine sites cored on Hydrate Ridge. The LWD tools used during Leg 204 were provided by Schlumberger, they included the resistivity-at-the-bit (RAB-GVR) tool, the magnetic resonance while drilling (MRWD) tool, and the azimuthal density-neutron (VDN) tool. It has been shown that it is possible to obtain gas-hydrate saturations (percent of pore space occupied by gas hydrate) by using the Archie relation to analyze the electrical resistivity of gas-hydrate-bearing sediments. In this study, the Archie relation was used with resistivity data from the GVR tool and porosity data from the VDN density tool to calculate water saturations at all eight LWD log sites on Hydrate Ridge. The downhole log inferred distribution of gas hydrate beneath Hydrate Ridge and the adjacent slope basin is heterogeneous, with downhole RAB images showing gas hydrate occupying fractures and occurring as a disseminated pore-filling material within flat lying stratigraphic units with thicknesses varying from several centimeters to as much as 10 m. The Archie relation yielded water saturations ranging from low values near the crest of the ridge, of about 10% in Hole 1249A, to a more common value of about 90% along the flanks of the ridge. It is generally accepted that with the zone of gas hydrate stability, gas hydrate saturations (S_h) are the mathematical complement of Archie derived water saturations (S_w), with S_h=1-S_w. Thus, the Archie derived gas hydrate saturations at the crest of the ridge exceed 90%. It should be noted that the Archie relation cannot distinguish between the occurrence of free-gas and gas hydrate. But, neutron porosity logs from the VDN tool, which are sensitive to the occurrence of free gas, did not reveal the presence of any significant free-gas occurrence above the depth of the BSR on Hydrate Ridge.

Collett, T.; Goldberg, D.; Guerin, G.; Barr, S.; Leg 204 Shipboard Scientific Party, I.

2003-04-01

346

Electronic neutron sources for compensated porosity well logging  

NASA Astrophysics Data System (ADS)

The viability of replacing Americium-Beryllium (Am-Be) radiological neutron sources in compensated porosity nuclear well logging tools with D-T or D-D accelerator-driven neutron sources is explored. The analysis consisted of developing a model for a typical well-logging borehole configuration and computing the helium-3 detector response to varying formation porosities using three different neutron sources (Am-Be, D-D, and D-T). The results indicate that, when normalized to the same source intensity, the use of a D-D neutron source has greater sensitivity for measuring the formation porosity than either an Am-Be or D-T source. The results of the study provide operational requirements that enable compensated porosity well logging with a compact, low power D-D neutron generator, which the current state-of-the-art indicates is technically achievable.

Chen, A. X.; Antolak, A. J.; Leung, K.-N.

2012-08-01

347

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

348

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

2013-01-01

349

Electromagnetic-induction logging to monitor changing chloride concentrations  

USGS Publications Warehouse

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 qualitypossibly 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.

Metzger, Loren F.; Izbicki, John A.

2013-01-01

350

Frequency independent parabolic phased antenna array of log periodic antennas  

NASA Astrophysics Data System (ADS)

A frequency-independent phased array antenna made of log-periodic radiators is presented which, in contrast to the Duhamel array, does not employ phase shifters at the antenna inputs to produce radiation in the main direction. The array considered here is a system of radial log-periodic radiators that form a parabolic phased-array antenna. The dipoles of all the radiators having the same size are located along a parabolic line. The operation of the parabolic array at various frequencies is equivalent to that of a series of confocal parabolic mirror antennas excited from a single source.

Veriga, B. A.; Vyakhirev, N. I.

1984-03-01

351

An expert system advisor for well log quality control  

E-print Network

, in identical formats for quality control of the sonic, gamma ray and dual induction well logs. A ~ial system program shell served as the fork for building the ~ system. The system has been written as a prototype model. With minimal alterations... PORTION OF THE WELL IOG QUALZIY CONTROL ~ SYSZEM ADVISOR APPENDIX C ? ~TION OF TAXONCMIES 59 59 62 TABLE OF CONTENTS (cont. ) DUAL INDUCTION IOG Page 64 APPENDIX D ? ~CE TREES FOR THE GAK% RAY, DUAL INDUCTION AND SONIC IOGS 68 GAMMA RAY LOG...

Warnken, Dean Kennedy

2012-06-07

352

Log-periodic oscillations of transverse momentum distributions  

E-print Network

Large p_T transverse momentum distributions exhibit apparently a power-like behavior. We argue that, under closer inspection, this behavior is in fact decorated with some log-periodic oscillations. Assuming that this is genuine effect and not experimental artefact, it suggests that either the exponent of the power-like behavior is in reality complex number or that there is a scale parameter which exhibits specific log-eriodic oscillations. This problem is discussed using Tsallis distributions with scale parameter being a temperature T.

Wilk, Grzegorz

2014-01-01

353

NADIR: Monitoring, Error Handling, and Logging with Tango  

NASA Astrophysics Data System (ADS)

The ingest and transport of a large amount of astronomical data, in geographically distributed archives, imply some challenging issues, like remote control and configuration, monitoring and logging anomalous conditions, fault tolerance and error handling. Based on this considerations and on our experience in data management, we started development of a New Archiving Distributed InfrastructuRe (NADIR), using Tango (Team 2013; S. Gara 2012), a well known distributed control system (DCSs) within scientific environments, taking advantage of its key features, like reliability, scalability, logging and alarm system, consolidated pattern and template, to solve this complexity. In this paper we discuss about design choices and technical aspects around this project.

De Marco, M.; Knapic, C.; Smareglia, R.

2014-05-01

354

A Small Planar Log-Periodic Koch-Dipole Antenna (LPKDA)  

E-print Network

A Small Planar Log-Periodic Koch-Dipole Antenna (LPKDA) Dimitrios E. Anagnostou*(1) , John Abstract--Koch dipole elements are introduced in a planar log-periodic dipole antenna array, in order, Log-periodic I. INTRODUCTION Log-periodic dipole antenna (LPDAs) arrays used in radio signal detection

Tentzeris, Manos

355

Effects of Logging on Stand Damage in the Rainforest of South-eastern Nigeria  

Microsoft Academic Search

Study was carried out in the tropical high forest of Iwuru community in south-eastern Nigeria to examine the extent of stand damage to unlogged trees at different logging intensities. Twenty four plots of 1 ha each were laid and were classified as lightly logged, moderately logged, severely logged and unlogged (control). Each category had six plots. Data on level of

F. E. Bisong; P. Mfon

356

Meta-Analysis of Mass Balances Examining Chemical Fate during Wastewater Treatment  

PubMed Central

Mass balances are an instructive means for investigating the fate of chemicals during wastewater treatment. In addition to the aqueous-phase removal efficiency (?), they can inform on chemical partitioning, transformation, and persistence, as well as on the chemical loading to streams and soils receiving, respectively, treated effluent and digested sewage sludge (biosolids). Release rates computed on a per-capita basis can serve to extrapolate findings to a larger scale. This review examines over a dozen mass balances conducted for various organic wastewater contaminants, including prescription drugs, estrogens, fragrances, antimicrobials, and surfactants of differing sorption potential (hydrophobicity), here expressed as the 1-octanol?water partition coefficient (KOW) and the organic carbon normalized sorption coefficient (KOC). Major challenges to mass balances are the collection of representative samples and accurate quantification of chemicals in sludge. A meta-analysis of peer-reviewed data identified sorption potential as the principal determinant governing chemical persistence in biosolids. Occurrence data for organic wastewater compounds detected in digested sludge followed a simple nonlinear model that required only KOW or KOC as the input and yielded a correlation coefficient of 0.9 in both instances. The model predicted persistence in biosolids for the majority (>50%) of the input load of organic wastewater compounds featuring a log10KOW value of greater than 5.2 (log10KOC > 4.4). In contrast, hydrophobicity had no or only limited value for estimating, respectively, ? and the overall persistence of a chemical during conventional wastewater treatment. PMID:18800497

2008-01-01

357

Effects of variable retention logging in the boreal forest on the bumble bee-influenced pollination community, evaluated 89 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 89 years after experimental variable retention logging. Harvest treatments left 0%, 1020%, 5075%, or 100% of the

Chris J. Pengelly; Ralph V. Cartar

2010-01-01

358

Ethanol and ambrosia beetles in Douglas fir logs with and without branches  

Microsoft Academic Search

November-felled Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) logs with and without branches were left lying on the forest floor through August. In May, as the logs were being colonized by ambrosia beetles,Trypodendron lineatum (Oliv.) andGnathotrichus retusus (LeConte), the ethanol, acetaldehyde, and water concentrations in the delimbed logs were significantly higher than in the branched logs. Since both log types received

Rick G. Kelsey

1994-01-01

359

Reduction of lithologic-log data to numbers for use in the digital computer  

USGS Publications Warehouse

The development of a standardized system for conveniently coding lithologic-log data for use in the digital computer has long been needed. The technique suggested involves a reduction of the original written alphanumeric log to a numeric log by use of computer programs. This numeric log can then be retrieved as a written log, interrogated for pertinent information, or analyzed statistically. ?? 1971 Plenum Publishing Corporation.

Morgan, C.O.; McNellis, J.M.

1971-01-01

360

The design and implementation of a log-structured file system  

Microsoft Academic Search

This paper presents a new technique for disk storage management called a log-structured file system. A log-structured file system writes all modifications to disk sequentially in a log-like structure, thereby speeding up both file writing and crash recovery. The log is the only structure on disk; it contains indexing information so that files can be read back from the log

Mendel Rosenblum; John K. Ousterhout

1992-01-01

361

Ethics, Logs and Videotape: Ethics in Large Scale User Trials  

E-print Network

, physical motion and ambient audio to automatically update social networking sites with his/her current activity. Hungry Yoshi [10], in addition to gathering log data on user interactions and location, also to the Facebook iPhone application update sharing phone numbers [14] and researchers at U. Bath covertly tracking

Paris-Sud XI, Université de

362

Report Exec Administrator Clery Act Public Crime Log  

E-print Network

Report Exec Administrator Clery Act Public Crime Log From 12/1/2013 To 12/31/2013 Incident Type that person or persons removed laptop computer from a chair located inside the residence; two subjects charged that person or persons removed laptop computer from a chair located inside the residence; two subjects charged

Boyce, Richard L.

363

Log in to Clarity RGMS Go to Conflicts of Interest  

E-print Network

KEY: Log in to Clarity RGMS Go to Conflicts of Interest (Under "Assessments") READ Conflicts of Interest Instructions (Under "Conflict of Interest" Tab Click on "Assessors" Tab Once you have finished reading Select "Round" Note: Round information can be found in the notification email sent to you Click

364

Anomalous effects of a log-periodic dipole antenna  

NASA Astrophysics Data System (ADS)

A numerical method is proposed which is used to study the anomalous behavior of a log-periodic dipole antenna or array in a rigorous electrodynamic framework. Results are presented for an antenna consisting of seven vibrators with a similarity coefficient tau = 0.9 and an apex angle 2 alpha = 57 deg.

Kudin, V. P.; Shlyk, N. I.; Ruban, A. P.

1985-03-01

365

The Series-Fed, LOG-Periodic Folded Dipole Array.  

National Technical Information Service (NTIS)

The antenna described is a new type of unidirectional, plane-polarized, log-periodic antenna array in which the elements are folded dipoles connected in series with the wires of a feeder. In comparison with similar arrays of straight dipoles, the models t...

K. G. Balmain, J. D. Dyson

1964-01-01

366

The Log-effect for p-evolution type models  

Microsoft Academic Search

The goal of the paper is to study the Log-effect for special $p$ -evolution type models. The loss of regularity is related in an optimal way due to some unboundedness conditions for the derivatives of coefficients up to the second order with respect to $t$ . Some counter-examples show that these conditions are sharp. We present the state of art

Massimo CICOGNANI; Fumihiko HIROSAWA; Michael REISSIG

2008-01-01

367

Organic Matter Content of Soil After Logging of Fir  

E-print Network

affects erodibility,1 infiltration,2 water reten- tion,3 and shear strength of soil.4 Organic matterOrganic Matter Content of Soil After Logging of Fir and Redwood Forests Philip B. Durgin United.O. Box 245 Berkeley California 94701 Research Note PSW-346 October 1980 rganic matter influences physical

Standiford, Richard B.

368

Instructional Conversations and Literature Logs. What Works Clearinghouse Intervention Report  

ERIC Educational Resources Information Center

This What Works Clearinghouse (WWC) report examines the effect of "Instructional Conversations and Literature Logs" used in combination. The goal of "Instructional Conversations" is to help English language learners develop reading comprehension ability along with English language proficiency. "Instructional Conversations" are small-group

What Works Clearinghouse, 2006

2006-01-01

369

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

370

Dual-cone double-helical downhole logging device  

DOEpatents

A broadband downhole logging device includes a double-helix coil wrapped over a dielectric support and surrounded by a dielectric shield. The device may also include a second coil longitudinally aligned with a first coil and enclosed within the same shield for measuring magnetic permeability of downhole formations and six additional coils for accurately determining downhole parameters.

Yu, Jiunn S. (Albuquerque, NM)

1984-01-01

371

Vol. 45, No. 3 December 2001 Mariners Weather Log  

E-print Network

Log U.S. DEPARTMENT OF COMMERCE Donald L. Evans, Secretary National Oceanic and Atmospheric that Santa Claus, Criscringle, Father Christmas, Father Frost, Père Noël Joulupukki, Kris Kringle, Sabdiklos, Saint Nicolas, Sancte Claus, Sinter Klaas, or Weinachtsmann brings you all that you hope for and more

372

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

373

Extracting the textual and temporal structure of supercomputing logs  

Microsoft Academic Search

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

Sourabh Jain; Inderpreet Singh; Abhishek Chandra; Zhi-Li Zhang; Greg Bronevetsky

2009-01-01

374

Design of a stripline log-periodic dipole antenna  

Microsoft Academic Search

A procedure is given for designing a two-layer stripline log-periodic dipole (LPD) antenna array. Measured input impedance and far-field characteristics are demonstrated for a 12-element array for 1-2 GHz operation that are in good agreement with design specifications.

C. Campbell; I. Traboulay; M. Suthers; H. Kneve

1977-01-01

375

Log-periodic antennas with modulated impedance feeders  

Microsoft Academic Search

The proper phasing of the active region of a log-periodic array can be obtained by means of a feeder without the conventional transposition of the wires. This is of practical importance for arrays of monopoles and slots where the transposition is not possible. However, the input impedance of such structures, when fed from a line with constant impedance, varies greatly

P. Ingerson; P. Mayes

1968-01-01

376

On transient radiation from a log-periodic dipole array  

Microsoft Academic Search

An analysis of how a transient voltage is radiated from a log-periodic dipole array is presented by adopting an idealized model of the array. Due to the frequency dependent phase center location of the array and an assumed slow wave phase velocity which varies logarithmically with frequency, a time delay which decreases with increasing frequency results. This causes the envelope

C. Knop

1970-01-01

377

Note on log-periodic description of 2008 financial crash  

E-print Network

We analyze the financial crash in 2008 for different financial markets from the point of view of log-periodic function model. In particular, we consider Dow Jones index, DAX index and Hang Seng index. We shortly discuss the possible relation of the theory of critical phenomena in physics to financial markets.

Bolonek-Lason, Katarzyna

2010-01-01

378

An analysis of Log Periodic Antenna with Printed Dipoles  

Microsoft Academic Search

An analysis of Log Periodic Antenna with Printed Dipoles is presented here. In this analysis, the wave equation for Hertz potential is solved in Cartesian coordinates applying the boundary conditions of a flat strip dipole. Using this model, the input currents to the antenna elements, the current distribution of the antenna elements, and the radiation pattern are computed. The computed

A. Paul; I. Gupta

1981-01-01

379

Note on log-periodic description of 2008 financial crash  

NASA Astrophysics Data System (ADS)

We analyse the financial crash in 2008 for different financial markets from the point of view of log-periodic function model. In particular, we consider Dow Jones index, DAX index and Hang Seng index. We shortly discuss the possible relation of the theory of critical phenomena in physics to financial markets.

Bolonek-Lason, Katarzyna; Kosinski, Piotr

2011-11-01

380

The design of nine element quasi microstrip log periodic antenna  

Microsoft Academic Search

This paper described the design, simulation and fabrication of the inset feed log periodic antenna with nine elements. The antennas have been modeled using microstrip lines and S parameter data from an individual single element. The data is extracted from the simulation and combined with the microstrip transmission line. The properties of antennas such as bandwidth, gain, cross-polar isolation and

M. K. A. Rahim; P. Gardner

2004-01-01

381

An approach for mining service composition patterns from execution logs  

E-print Network

effectively detect service composition patterns. Copyright © 2012 John Wiley & Sons, Ltd. Received 28 February 2011; Revised 2 May 2012; Accepted 5 June 2012 KEY WORDS: component; Web service; composition; patternAn approach for mining service composition patterns from execution logs Bipin Upadhyaya, Ran Tang

Zou, Ying

382

Foundation Investigation at Hickory Log Creek Dam, Canton, Georgia  

Microsoft Academic Search

Hickory Log Creek Dam is a proposed 55 meter high roller compacted concrete dam located on a tributary of the Etowah River near Canton, Georgia. The site characterization involved several app roaches that facilitated the rapid foundation investigation schedule. These included identification of critical data needs, design of the program to collect these data, and selection of preferred data acquisition

Gary D. Rogers; Chuck Kahler; Scott Deaton

383

Determination of true static formation temperature from well logs  

SciTech Connect

Several concepts that attempt to determine static (true) formation temperature from log-derived BHT measurements with and without knowledge of drilling fluid circulation time have been reviewed. Whereas several refined models are available, the simple Horner-type technique provides quick and reliable static (true) formation temperature estimates.

Fertl, W.H.; Chilingarian, G.V.; Yen, T.F.

1986-01-01

384

1. OVERVIEW OF AREA B OF SITE, SHOWING LOG BUILDING ...  

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

1. OVERVIEW OF AREA B OF SITE, SHOWING LOG BUILDING AND BUNKHOUSE AT LEFT (Features 9 and 10), RUIN AND SHED IN CENTER (Features 11 and 12), AND HOUSE RUIN AT RIGHT (Feature 13), LOOKING EAST-NORTHEAST - Gold Dust Mine, Mill & Camp Complex, Wards Gulch, Salmon, Lemhi County, ID

385

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

386

$L\\\\log L$ condition for supercritical branching Hunt processes  

Microsoft Academic Search

In this paper we use the spine decomposition and martingale change of measure to establish a Kesten-Stigum $L\\\\log L$ theorem for branching Hunt processes. This result is a generalization of the results in Asmussen-Hering (1976) and Hering (1978) for branching diffusions.

Rong-Li Liu; Yan-Xia Renand; Renming Song

2010-01-01

387

Lehman Review Recommendation dispositon log Date Ref Review  

E-print Network

Lehman Review Recommendation dispositon log Date Ref Review Ite m Concern October 2011 Lehman Review 2.1 Develop a plan for a set of diagnostics for measuring halo currents 201110 - L02 October 2011 Lehman Review 2.2 Evaluate procuring spare key fabrication tooling ( e

Princeton Plasma Physics Laboratory

388

FRACTURE RESERVOIR CHARACTERIZATION BY FIBER-OPTIC DISTRIBUTED TEMPERATURE LOG  

Microsoft Academic Search

One of the important features of the fiber-optic distributed temperature log is its ability to acquire continuous, instantaneous and simultaneous temperature profile along the entire wellbore. Series of successive temperature profiles sampled every one minute or so enable to analyze transient temperature phenomena, which may pertain to important reservoir properties. For example, when change of rate occurred to the fluid

Naotsugu IKEDA

389

Determining In-Situ Stress Profiles From Logs.  

E-print Network

study. #12;18 SPE 90070 Shahab D. Mohaghegh Methodology Neural Networks were used to develop an in1 Determining In-Situ Stress Profiles From Logs. Shahab D. Mohaghegh West Virginia University regarding in-situ stress. An important factor in designing successful hydraulic fractures. #12;4 SPE 90070

Mohaghegh, Shahab

390

Field Trip Guide and Road Log: Tracking Hydraulic Mining Sediment  

E-print Network

Field Trip Guide and Road Log: Tracking Hydraulic Mining Sediment in the Sierra Foothills and Space Sciences, Univ. Washington, Seattle- aalto@u.washington.edu Crevasse splays and natural levee.C. Davis map library. #12;Tracking Hydraulic Mining Sediment James, Singer, and Aalto Page 1 Field Trip

Singer, Michael

391

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

392

Filtering Log Data: Finding the Needles in the Haystack  

E-print Network

developed from Sandia National Lab can collect various state variables (e.g., temperature, CPU utilization Laboratory Oak Ridge, TN 37831, USA trjones@ornl.gov Jim M. Brandt, Ann C. Gentile Sandia National Laboratories Livermore, CA 94551, USA {brandt, gentile}@sandia.gov Abstract--Log data is an incredible asset

Sun, Xian-He

393

Towards Forensic Data Flow Analysis of Business Process Logs  

Microsoft Academic Search

This paper presents RECIF, a forensic technique for the analysis of business process logs to detect illegal data flows. RECIF uses propagation graphs to formally capture the data flow within a process execution. Abstracting away from the concrete traces, propagation graphs are analyzed with extensional data flow policies that denote what ? instead of how ? relevant industrial requirements, e.g.

Rafael Accorsi; Claus Wonnemann; Thomas Stocker

2011-01-01

394

A Dual Actuator Logging Disk Architecture John A. Chandy  

E-print Network

architectures. A hard disk drive is composed of one or many circular platters or disks coated with a magnetic at an increas- ingly faster rate and studies have suggested that the amount of information stored digitallyA Dual Actuator Logging Disk Architecture John A. Chandy Department of Electrical and Computer

Chandy, John A.

395

Towards sharing life-log information with society  

Microsoft Academic Search

We are living in an era of social media such as online communities and social networking sites. Exposing or sharing personal information with these communities has risks as well as benefits and there is always a trade off between the risks versus the benefits of using these technologies. Life-logs are pervasive tools or systems which sense and capture contextual information

Reza Rawassizadeh

2012-01-01

396

Logging and Recovery in Adaptive Software Distributed Shared Memory Systems  

Microsoft Academic Search

Software distributed shared memory (DSM) improves the programmability of message-passing machines and work- station clusters by providing a shared memory abstract (i.e., a coherent global address space) to programmers. As in any distributed system, however, the probability of software DSM failures increases as the system size grows. This pa- per presents a new, efficient logging protocol for adaptive software DSM

Angkul Kongmunvattana; Nian-feng Tzeng

1999-01-01

397

Estimating the service time of web clients using server logs  

Microsoft Academic Search

This article proposes and evaluates measures for estimating the service time of a web client using server logs, only from the server side without introducing traffic into the network. The HTTP protocol is described as well as the different interactions between the web server, the communication components, and the web client application. The first measure is based on the time

Oscar Ardaiz; Felix Freitag; Leandro Navarro

2001-01-01

398

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

399

Future Internet Security Services Enabled by Sharing of Anonymized Logs  

Microsoft Academic Search

As security monitoring grows more complicated, there is an increased demand for outsourcing these tasks for to Managed Security Service Providers (MSSPs). However, the core problem of sharing private data creates a barrier to the widespread adoption of this business model. In this position paper we propose an anonymization solution that promotes sharing logs with MSSPs while simultaneously protecting privacy.

Jianqing Zhang; Nikita Borisov; William Yurcik; Adam J. Slagell; Matthew Smith

400

Secure Logging of Retained Data for An Anonymity Service  

E-print Network

Secure Logging of Retained Data for An Anonymity Service Stefan K�psell1 and Petr Svenda2 1 TU@fi.muni.cz> Abstract. The recently introduced legislation on data retention to aid prosecuting cyber-related crime in Europe also affects the achievable se- curity of systems for anonymous communication on the Internet. We

Boyer, Edmond

401

Towards Publishable Event Logs That Reveal Touchscreen Faults  

E-print Network

accessibility through multilingual and multi- modal interfaces. The Help America Vote Act mandated "at least one}@cs.uiowa.edu Douglas W. Jones Abstract Federal standards require that electronic voting machines log information about the voting system behavior to sup- port post-election audits and investigations. Our study examines interface

Jones, Douglas W.

402

Logging the Interpretive Act: Dialogical Interaction in the Literature Classroom.  

ERIC Educational Resources Information Center

Disclosing interpretation as a meaning-making process of the active mind to students in all humanities courses, and especially in literature classes, is possible in numerous, phased writing assignments with built-in exercises in recursive and reflective thinking. The exercises are written down in each student's log (journal), a process which

McNeil, Lynda D.

403

44. View of log boom (downstream) protecting fish screens at ...  

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

44. View of log boom (downstream) protecting fish screens at Dingle Basin, looking northeast from south side of basin. Photo by Brian C. Morris, Puget Power, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

404

43. View of log boom (upstream) protecting fish screens at ...  

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

43. View of log boom (upstream) protecting fish screens at Dingle Basin, looking southwest from north side of basin. Photo by Brian C. Morris, PUget Power, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

405

Development, Implementation and Assessment of a Progressive Reading Log System  

NSDL National Science Digital Library

Students in upper-level Engineering classes such as Fluid Mechanics often find themselves faced with over 60 pages of reading a week in addition to assigned problems and exam preparation. Since the reading of the textbook is often infrequently assessed, this aspect of course learning is often postponed or omitted. In addition, with this amount of reading, many students quickly find themselves so far behind in the reading that they can no longer catch up. A reading log system where content responsibility is progressively shifted from the instructors questions to student identification and reflection has been developed and implemented in junior-level Fluid Mechanics and Thermodynamics courses to address several of the issues associated with student use of the textbook. The goal of the reading log is to improve student use of resource material and to provide opportunities for students to develop skills in reading scientific material. Reflective questioning, guided identification of key concepts, probing questions and cyclic problems are some of the tools that are used to stimulate student use of the textbook. In addition, the progressive content of the reading logs is designed to transition the student from rote learning to self-reflection and synthesis of understanding. To evaluate the effectiveness of the resource, student surveys and responses to reading log questions have beenused to guide its development.

Benson, Daniel

2011-05-03

406

A small-diameter NMR logging tool for groundwater investigations.  

PubMed

A small-diameter nuclear magnetic resonance (NMR) logging tool has been developed and field tested at various sites in the United States and Australia. A novel design approach has produced relatively inexpensive, small-diameter probes that can be run in open or PVC-cased boreholes as small as 2 inches in diameter. The complete system, including surface electronics and various downhole probes, has been successfully tested in small-diameter monitoring wells in a range of hydrogeological settings. A variant of the probe that can be deployed by a direct-push machine has also been developed and tested in the field. The new NMR logging tool provides reliable, direct, and high-resolution information that is of importance for groundwater studies. Specifically, the technology provides direct measurement of total water content (total porosity in the saturated zone or moisture content in the unsaturated zone), and estimates of relative pore-size distribution (bound vs. mobile water content) and hydraulic conductivity. The NMR measurements show good agreement with ancillary data from lithologic logs, geophysical logs, and hydrogeologic measurements, and provide valuable information for groundwater investigations. PMID:23425428

Walsh, David; Turner, Peter; Grunewald, Elliot; Zhang, Hong; Butler, James J; Reboulet, Ed; Knobbe, Steve; Christy, Tom; Lane, John W; Johnson, Carole D; Munday, Tim; Fitzpatrick, Andrew

2013-01-01

407

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

408

Integrated NMR Core and Log Investigations With Respect to ODP LEG 204  

NASA Astrophysics Data System (ADS)

NMR techniques are widely used in the oil industry and are one of the most suitable methods to evaluate in-situ formation porosity and permeability. Recently, efforts are directed towards adapting NMR methods also to the Ocean Drilling Program (ODP) and the upcoming Integrated Ocean Drilling Program (IODP). We apply a newly developed light-weight, mobile NMR core scanner as a non-destructive instrument to determine routinely rock porosity and to estimate the pore size distribution. The NMR core scanner is used for transverse relaxation measurements on water-saturated core sections using a CPMG sequence with a short echo time. A regularized Laplace-transform analysis yields the distribution of transverse relaxation times T2. In homogeneous magnetic fields, T2 is proportional to the pore diameter of rocks. Hence, the T2 signal maps the pore-size distribution of the studied rock samples. For fully saturated samples the integral of the distribution curve and the CPMG echo amplitude extrapolated to zero echo time are proportional to porosity. Preliminary results show that the NMR core scanner is a suitable tool to determine rock porosity and to estimate pore size distribution of limestones and sandstones. Presently our investigations focus on Leg 204, where NMR Logging-While-Drilling (LWD) was performed for the first time in ODP. Leg 204 was drilled into Hydrate Ridge on the Cascadia accretionary margin, offshore Oregon. All drilling and logging operations were highly successful, providing excellent core, wireline, and LWD data from adjacent boreholes. Cores recovered during Leg 204 consist mainly of clay and claystone. As the NMR core scanner operates at frequencies higher than that of the well-logging sensor it has a shorter dead time. This advantage makes the NMR core scanner sensitive to signals with T2 values down to 0.1 ms as compared to 3 ms in NMR logging. Hence, we can study even rocks with small pores, such as the mudcores recovered during Leg 204. We present a comparison of data from core scanning and NMR logging. Future integration of conventional wireline data and electrical borehole wall images (RAB/FMS) will provide a detailed characterization of the sediments in terms of lithology, petrophysics and, fluid flow properties.

Arnold, J.; Pechnig, R.; Clauser, C.; Anferova, S.; Blmich, B.

2005-12-01

409

Evaluation of estimation methods for organic carbon normalized sorption coefficients  

USGS Publications Warehouse

A critically evaluated set of 94 soil water partition coefficients normalized to soil organic carbon content (Koc) is presented for 11 classes of organic chemicals. This data set is used to develop and evaluate Koc estimation methods using three different descriptors. The three types of descriptors used in predicting Koc were octanol/water partition coefficient (Kow), molecular connectivity (mXt) and linear solvation energy relationships (LSERs). The best results were obtained estimating Koc from Kow, though a slight improvement in the correlation coefficient was obtained by using a two-parameter regression with Kow and the third order difference term from mXt. Molecular connectivity correlations seemed to be best suited for use with specific chemical classes. The LSER provided a better fit than mXt but not as good as the correlation with Koc. The correlation to predict Koc from Kow was developed for 72 chemicals; log Koc = 0.903* log Kow + 0.094. This correlation accounts for 91% of the variability in the data for chemicals with log Kow ranging from 1.7 to 7.0. The expression to determine the 95% confidence interval on the estimated Koc is provided along with an example for two chemicals of different hydrophobicity showing the confidence interval of the retardation factor determined from the estimated Koc. The data showed that Koc is not likely to be applicable for chemicals with log Kow Koc correlation developed using Kow as a descriptor was compared with three nonclass-specific correlations and two 'commonly used' class-specific correlations to determine which method(s) are most suitable.

Baker, James R.; Mihelcic, James R.; Luehrs, Dean C.; Hickey, James P.

1997-01-01

410

Carbon emissions performance of commercial logging in East Kalimantan, Indonesia.  

PubMed

Adoption of reduced-impact logging (RIL) methods could reduce CO2 emissions by 30-50% across at least 20% of remaining tropical forests. We developed two cost effective and robust indices for comparing the climate benefits (reduced CO2 emissions) due to RIL. The indices correct for variability in the volume of commercial timber among concessions. We determined that a correction for variability in terrain slope was not needed. We found that concessions certified by the Forest Stewardship Council (FSC, N=3), when compared with noncertified concessions (N=6), did not have lower overall CO2 emissions from logging activity (felling, skidding, and hauling). On the other hand, FSC certified concessions did have lower emissions from one type of logging impact (skidding), and we found evidence of a range of improved practices using other field metrics. One explanation of these results may be that FSC criteria and indicators, and associated RIL practices, were not designed to achieve overall emissions reductions. Also, commonly used field metrics are not reliable proxies for overall logging emissions performance. Furthermore, the simple distinction between certified and noncertified concessions does not fully represent the complex history of investments in improved logging practices. To clarify the relationship between RIL and emissions reductions, we propose the more explicit term 'RIL-C' to refer to the subset of RIL practices that can be defined by quantified thresholds and that result in measurable emissions reductions. If tropical forest certification is to be linked with CO2 emissions reductions, certification standards need to explicitly require RIL-C practices. PMID:24022913

Griscom, Bronson; Ellis, Peter; Putz, Francis E

2014-03-01

411

Values in Education and Education in Values.  

ERIC Educational Resources Information Center

The major purpose of this book is to set out some of the key issues and debates relating to the importance of values in education and of education in values. After an introductory chapter about the concept of values and values education, part 1 provides a variety of perspectives on the values that underpin contemporary education. The introduction

Halstead, J. Mark, Ed.; Taylor, Monica J., Ed.

412

Multiple populations on the horizontal branch. I - Observations in the (log g, log T/eff/)-diagram  

NASA Technical Reports Server (NTRS)

Log T(eff) and log g have been determined for blue horizontal branch (HB) stars in the globular clusters M15, M3, M5, M92, and NGC 288 as a first step in determining the physical origin of gaps or bimodal distributions in the blue horizontal branches of a number of globular clusters. The (log g, log T/eff/) diagram for the 'normal' HB cluster M5 matches the standard theory quite well. The stars blueward of the gap in NGC 288 and the blue extension of the M3 HB have significantly lower gravity than predicted by the standard theory. The cooler stars in M3 agree well with the standard theory while those of NGC 2988 lie at slightly lower gravity. In M92, the sequence of stars is broadened toward the low gravity side more than expected either from standard evolution or from observational error. The data for M15 are too scattered to support firm conclusions but seem consistent with NGC 288.

Crocker, Deborah A.; Rood, Robert T.; O'Connell, Robert W.

1988-01-01

413

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

414

UBC Social Ecological Economic Development Studies (SEEDS) Student Report The Utilization of Small Diameter Douglas Fir: The Viability of the Log Furniture Market  

E-print Network

............................................................................................................ 12 Log/Timber Frame Homeowners ...................................................................................... 14 Commercial Log and Timber Frame Home Producers

415

Iterative Non-hierarchical Cluster Analysis (INCA): a novel approach to analysing downhole logging and petrophysical data  

NASA Astrophysics Data System (ADS)

Iterative Non-Hierarchical Cluster Analysis (INCA) is a multivariate statistical approach used to analyse data, suited to large datasets where a defined number of clusters can be hypothesised. Although the fundamentals of this methododology are well-known, its use for the analysis of downhole logging and petrophysical measurements is a novel approach for quantitatively interpreting these datasets. Cluster analysis works by starting with k random clusters then grouping the set of data such that values within a cluster are more similar to each other than to those in the other clusters i.e. to minimise variability within a cluster and maximise variability between clusters. INCA provides a valuable tool for understanding downhole logging and petrophysical datasets by interpreting the weightings attached to each cluster in terms of petrophysical characteristics. The INCA program has been successfully used on datasets from varied geological environments to characterise formations based on their petrophsyical properties alone. Here, we discuss details of the specific algorithms chosen, size constraints and departures from standard commercially available packages. We present examples of results that use a variety of different petrophysical parameters; from spectral gamma ray logs used to independently assess lithology, to resisitivity and sonic logs used to identify the position of major boundaries. Examples of the methodology applied to subduction zone accretionary prism sediments (IODP Expedition 314), oceanic crustal rocks (e.g. ODP Hole 735B) and from continental shelf siliciclastic sediments (IODP Expedition 313) are illustrated.

Inwood, J.; Tudge, J.; Harvey, P.

2012-12-01

416

Empirical Models for Dark Matter Halos. III. The Kormendy relation and the log(rho_e)-log(R_e) relation  

E-print Network

We have recently shown that the 3-parameter density-profile model from Prugniel & Simien provides a better fit to simulated, galaxy- and cluster-sized, dark matter halos than an NFW-like model with arbitrary inner profile slope gamma (Paper I). By construction, the parameters of the Prugniel-Simien model equate to those of the Sersic R^{1/n} function fitted to the projected distribution. Using the Prugniel-Simien model, we are therefore able to show that the location of simulated (10^{12} M_sun) galaxy-sized dark matter halos in the _e-log(R_e) diagram coincides with that of brightest cluster galaxies, i.e., the dark matter halos appear consistent with the Kormendy relation defined by luminous elliptical galaxies. These objects are also seen to define the new, and equally strong, relation log(rho_e) = 0.5 - 2.5log(R_e), in which rho_e is the internal density at r=R_e. Simulated (10^{14.5} M_sun) cluster-sized dark matter halos and the gas component of real galaxy clusters follow the relation log(rho_e) = 2.5[1 - log(R_e)]. Given the shapes of the various density profiles, we are able to conclude that while dwarf elliptical galaxies and galaxy clusters can have dark matter halos with effective radii of comparable size to the effective radii of their baryonic component, luminous elliptical galaxies can not. For increasingly large elliptical galaxies, with increasingly large profile shapes `n', to be dark matter dominated at large radii requires dark matter halos with increasingly large effective radii compared to the effective radii of their stellar component.

Alister W. Graham; David Merritt; Ben Moore; Juerg Diemand; Balsa Terzic

2006-08-29

417

Geothermal regime of Tarim basin, NW China: insights from borehole temperature logging  

NASA Astrophysics Data System (ADS)

Geothermal regime of sedimentary basin is vital for understanding basin (de)formation process, hydrocarbon generation status and assessing the resource potential. Located at the Precambrian craton block, the Tarim basin is the largest intermountain basin in China, which is also the ongoing target of oil and gas exploration. Previous knowledge of thermal regime of this basin is from limited oil exploration borehole testing temperature, the inherent deficiency of data of this type makes accurate understanding of its thermal regime impossible. Here we reported our latest steady temperature logging results in this basin and analyze its thermal regime as well. In this study, 10 temperature loggings are conducted in the northern Tarim basin where the major oil and gas fields are discovered. All the boreholes for temperature logging are non-production wells and are shut in at least more than 2~3 years, ensuring the temperature equilibrium after drilling. The derived geothermal gradient varies from 20.2 to 26.1 degree/km, with a mean of 22.0 degree/km. However, some previous reported gradients in this area are obviously lower than our results; for example, the previous gradient of THN2 well is 13.2 degree/km but 23.2 degree/km in this study, and not enough equilibrium time in previous logging accounts for this discrepancy. More important, it is found that high gradients usually occur in the gas field and the gradients of the gas fields are larger than those in other oil fields, indicating higher thermal regime in gas field. The cause of this phenomenon is unclear, and the upward migration of hot fluid along fault conduit is speculated as the possible mechanism for this high geothermal anomaly in the oil and gas fields. Combined with measured thermal conductivity data, 10 new heat flow values are also achieved, and the heat flow of the Tarim basin is between 38mW/m2 and 52mW/m2, with a mean of 43 mW/m2. This relatively low heat flow is coincident with that of typical Precambrian craton basin in the world, considering that the Tarim basin has not experienced obvious Meso-Cenozoic tectono-thermal events after its formation. The heat flow distribution of the Tarim basin is characterized by large values in the uplift areas and low in the depressions, showing the influence of lateral contrast in thermal properties within the basin on present-day geothermal regime.

Liu, S.; Lei, X.

2013-12-01

418

Rock Mechanical Properties from Logs Petrophysics : Concepts and Results  

NASA Astrophysics Data System (ADS)

The objective of the "geomechanics from logs" (GML) research project is to develop model-driven predictive software for determining rock mechanical properties (specifically rock strength, compressibility and fracability) from other, more easily measured, rock properties (e.g. lithology, porosity, clay volume, velocity) routinely derived from nuclear, resistivity and acoustic logging tools. To this end, geomechanics from logs seeks to increase fundamental understanding of the primary geologic controls on rock mechanical properties and to translate this new insight into novel predictive tools. In detail, GML predictors rely on (i) the generation of relational rock mechanical properties databases incorporating QC'd core-based laboratory measurements (both in-house and high-precision published data); (ii) the use of established rock physics models (e.g. friable sand, contact cement models) to investigate theoretical relationships between geologic processes, reservoir environment, rock microstructure and elastic, bulk and transport petrophysical attributes/properties; (iii) the subdivision of database rocks into generic lithotypes (e.g. sand, shaly sand, sandy shale, shale) with common petrophysical attributes/properties; (iv) the use of multivariate statistics to generate lithotype-dependent empirical predictive relationships between mechanical properties and log-derived petrophysical attributes/properties; (v) the estimation of uncertainties associated with predictive function parameters; (vi) the application and validation of mechanical properties predictive tools to well-documented case studies (e.g. sand strength for perforation stability, rock compressibility for reservoir simulation) to test overall performance and quantify uncertainty in predictions. This paper presents the results of various rock strength, rock compressibility and rock fracability case studies conducted in wells of different stratigraphic age and depositional environment. Overall, GML (i) facilitated a step-change in fundamental (rock physics-based) understanding of complex geologic controls (rock microstructure and reservoir environment) on formation mechanical parameters; (ii) generated predictive algorithms relating core-derived rock mechanical parameters (specifically formation strength, compressibility and fracability) to petrophysical parameters determined directly from logging tools; and (iii) resulted in the implementation of these predictive algorithms and associated uncertainty quantification within log-analysis software.

Gaillot, Philippe; Crawford, Brian; Alramahi, Bashar; Karner, Steve

2010-05-01

419

Rolling Deck to Repository III: Shipboard Event Logging  

NASA Astrophysics Data System (ADS)

Data gathered during NSF-supported scientific research cruises represent an important component of the overall oceanographic data collection. The Rolling Deck to Repository (R2R) pilot project aims to improve access to basic shipboard data and ultimately reduce the work required to provide that access. Improved access will be achieved through identification of best practices for shipboard data management, identification of standard metadata and data products from research cruises, development of metadata schemas to describe a research cruise, and development of a prototype data discovery system that could be used by the entire NSF-supported academic research fleet. Shoreside data managers will work collaboratively with ship technicians and vessel operators to develop approaches that scale from smaller coastal vessels to larger open ocean research vessels. One of the coordinated subprojects within the R2R project will focus on development of a shipboard event logging system that would incorporate best practice guidelines, a metadata schema and new and existing applications to generate a scientific sampling event log in the form of a digital text file. A cruise event logging system enables researchers to record digitally all scientific sampling events and assign a unique event identifier to each entry. Decades of work conducted within large coordinated ocean research programs (JGOFS, GLOBEC, WOCE and RIDGE) have shown that creation of a shipboard sampling event log can facilitate greatly the subsequent integration of data sets from individual investigators. In addition to providing a quick way to determine what types of data might have been collected during a cruise, the sampling event log can be used to visualize the relationship, both temporally and geospatially, between the diverse types of sampling events conducted during a research cruise. Research questions in marine ecology or modeling projects are inherently multi-disciplinary and require access to a variety of data types. Improvements in cruise metadata reporting, including a sampling event log that could be contributed routinely to a centralized data repository, should improve access to research cruise data and facilitate accurate reuse of those data by colleagues.

Chandler, C. L.; Arko, R.; Miller, S. P.; Dorsk, A.; McCue, S.; Fisichella, D. C.

2008-12-01

420

Identification and Characterization of Hydrogeologic Units at the Nevada Test Site Using Geophysical Logs: Examples from the Underground Test Area Project  

SciTech Connect

The diverse and complex geology of the Nevada Test Site region makes for a challenging environment for identifying and characterizing hydrogeologic units penetrated by wells drilled for the U.S. Department of Energy, National Nuclear Security Administration, Underground Test Area (UGTA) Environmental Restoration Sub-Project. Fortunately, UGTA geoscientists have access to large and robust sets of subsurface geologic data, as well as a large historical knowledge base of subsurface geological analyses acquired mainly during the underground nuclear weapons testing program. Of particular importance to the accurate identification and characterization of hydrogeologic units in UGTA boreholes are the data and interpretation principles associated with geophysical well logs. Although most UGTA participants and stakeholders are probably familiar with drill hole data such as drill core and cuttings, they may be less familiar with the use of geophysical logs; this document is meant to serve as a primer on the use of geophysical logs in the UGTA project. Standard geophysical logging tools used in the UGTA project to identify and characterize hydrogeologic units are described, and basic interpretation principles and techniques are explained. Numerous examples of geophysical log data from a variety of hydrogeologic units encountered in UGTA wells are presented to highlight the use and value of geophysical logs in the accurate hydrogeologic characterization of UGTA wells.

Lance Prothro, Sigmund Drellack, Margaret Townsend

2009-03-25

421

The conservation value of South East Asia's highly degraded forests: evidence from leaf-litter ants  

PubMed Central

South East Asia is widely regarded as a centre of threatened biodiversity owing to extensive logging and forest conversion to agriculture. In particular, forests degraded by repeated rounds of intensive logging are viewed as having little conservation value and are afforded meagre protection from conversion to oil palm. Here, we determine the biological value of such heavily degraded forests by comparing leaf-litter ant communities in unlogged (natural) and twice-logged forests in Sabah, Borneo. We accounted for impacts of logging on habitat heterogeneity by comparing species richness and composition at four nested spatial scales, and examining how species richness was partitioned across the landscape in each habitat. We found that twice-logged forest had fewer species occurrences, lower species richness at small spatial scales and altered species composition compared with natural forests. However, over 80 per cent of species found in unlogged forest were detected within twice-logged forest. Moreover, greater species turnover among sites in twice-logged forest resulted in identical species richness between habitats at the largest spatial scale. While two intensive logging cycles have negative impacts on ant communities, these degraded forests clearly provide important habitat for numerous species and preventing their conversion to oil palm and other crops should be a conservation priority. PMID:22006966

Woodcock, Paul; Edwards, David P.; Fayle, Tom M.; Newton, Rob J.; Khen, Chey Vun; Bottrell, Simon H.; Hamer, Keith C.

2011-01-01

422

SedMob: A mobile application for creating sedimentary logs in the field  

NASA Astrophysics Data System (ADS)

SedMob is an open-source, mobile software package for creating sedimentary logs, targeted for use in tablets and smartphones. The user can create an unlimited number of logs, save data from each bed in the log as well as export and synchronize the data with a remote server. SedMob is designed as a mobile interface to SedLog: a free multiplatform package for drawing graphic logs that runs on PC computers. Data entered into SedMob are saved in the CSV file format, fully compatible with SedLog.

Wolniewicz, Pawel

2014-05-01

423

Borehole compensated density logs corrected for naturally occurring gamma rays  

SciTech Connect

A method for measuring formation density is disclosed. It provides a corrected gamma gamma-type density log having a correction for the adverse effects of gamma radiation from thorium, uranium and potassium ore bodies. The adjacent formation is irradiated with gamma radiation preferably from a cesium (Cs/sup 137/) source which emits gamma radiation at 0.663 Mev. Two differently longitudinally spaced detectors are used, a short spaced detector and a long spaced detector. A gamma ray spectrum observed at one of the detectors is broken down into four energy windows across the spectrum and count rate signals are determined and corrected to separate the naturally occurring gamma radiation from the scattered gamma radiation. This information may then be combined with count rate information from the other detector, thereby yielding a compensated density log corrected from naturally occurring gamma rays.

Arnold, D. M.

1985-07-16

424

What to expect when logging the Cotton Valley trend  

SciTech Connect

Exploration within the low-porosity, low-permeability sections of the Cotton Valley sands and limestones of E. Texas, Louisiana, and Arkansas has proven economic only within the last 5 to 8 yr due to improved gas prices and advanced reservoir analyzation and stimulation techniques. This work details those logging suites necessary to properly assess these less than optimum reservoirs, and illustrates, through specific well cases, how deliverability from well to well can vary due to delicate differences in reservoir properties. It is evident from the case wells illustrated that not all tight Cotton Valley sand or limestone wells result in high-rate flows. That being the case, it is important that detailed logging analysis be utilized so optimum stimulation procedures can be designed at each well site. Improperly place perforations or poorly designed and operated stimulation procedures can result in a bad well, where a successful one was possible.

Nangle, P.; Fertl, W.H.; Frost, E. Jr.

1982-10-01

425

Semantic annotation for live and posterity logging of video documents  

NASA Astrophysics Data System (ADS)

Broadcasters usually envision two basic applications for video databases: Live Logging and Posterity Logging. The former aims at providing effective annotation of video in quasi-real time and supports extraction of meaningful clips from the live stream; it is usually performed by assistant producers working at the same location of the event. The latter provides annotation for later reuse of video material and is the prerequisite for retrieval by content from video digital libraries; it is performed by trained librarians. Both require that annotation is performed, at a great extent, automatically. Video information structure must encompass both low-intermediate level video organization and event relationships that define specific highlights and situations. Analysis of the visual data of the video stream permits to extract hints, identify events and detect highlights. All of this must be supported by a-priori knowledge of the video domain and effective reasoning engines capable to capture the inherent semantics of the visual events.

Bertini, Marco; Del Bimbo, Alberto; Nunziati, W.

2003-06-01

426

Use of improved hydrologic testing and borehole geophysical logging methods for aquifer characterization  

SciTech Connect

Depth-discrete aquifer information was obtained using recently developed adaptations and improvements to conventional characterization techniques. These improvements included running neutron porosity and bulk density geophysical logging tools through a cased hole, performing an enhanced point-dilution tracer test for monitoring tracer concentration as a function of time and depth, and using pressure derivatives for diagnostic and quantitative analysis of constant rate discharge test data. Data results from the use of these techniques were used to develop a conceptual model of a heterogeneous aquifer. Depth-discrete aquifer information was required to effectively design field-scale deployment and monitoring of an in situ bioremediation technology. The bioremediation study site is located on the US Department of Energy`s Hanford site. The study is being conducted by the Pacific Northwest National Laboratory to demonstrate in situ bioremediation of carbon tetrachloride (CCl{sub 4}). Geophysical logging and point-dilution tracer test results provided the relative distribution of porosity and horizontal hydraulic conductivity, respectively, with depth and correlated well. Hydraulic pumping tests were conducted to estimate mean values for transmissivity and effective hydraulic conductivity. Tracer test and geophysical logging results indicated that ground water flow was predominant in the upper approximate 10 feet of the aquifer investigated. These results were used to delineate a more representative interval thickness for estimating effective hydraulic conductivity. Hydraulic conductivity, calculated using this representative interval, was estimated to be 73 ft/d, approximately three times higher than that calculated using the full length of the screened test interval.

Newcomer, D.R.; Hall, S.H.; Vermeul, V.R.

1996-05-01

427

Resistance and resilience of the forest soil microbiome to logging-associated compaction.  

PubMed

Soil compaction is a major disturbance associated with logging, but we lack a fundamental understanding of how this affects the soil microbiome. We assessed the structural resistance and resilience of the microbiome using a high-throughput pyrosequencing approach in differently compacted soils at two forest sites and correlated these findings with changes in soil physical properties and functions. Alterations in soil porosity after compaction strongly limited the air and water conductivity. Compaction significantly reduced abundance, increased diversity, and persistently altered the structure of the microbiota. Fungi were less resistant and resilient than bacteria; clayey soils were less resistant and resilient than sandy soils. The strongest effects were observed in soils with unfavorable moisture conditions, where air and water conductivities dropped well below 10% of their initial value. Maximum impact was observed around 6-12 months after compaction, and microbial communities showed resilience in lightly but not in severely compacted soils 4 years post disturbance. Bacteria capable of anaerobic respiration, including sulfate, sulfur, and metal reducers of the Proteobacteria and Firmicutes, were significantly associated with compacted soils. Compaction detrimentally affected ectomycorrhizal species, whereas saprobic and parasitic fungi proportionally increased in compacted soils. Structural shifts in the microbiota were accompanied by significant changes in soil processes, resulting in reduced carbon dioxide, and increased methane and nitrous oxide emissions from compacted soils. This study demonstrates that physical soil disturbance during logging induces profound and long-lasting changes in the soil microbiome and associated soil functions, raising awareness regarding sustainable management of economically driven logging operations. PMID:24030594

Hartmann, Martin; Niklaus, Pascal A; Zimmermann, Stephan; Schmutz, Stefan; Kremer, Johann; Abarenkov, Kessy; Lscher, Peter; Widmer, Franco; Frey, Beat

2014-01-01

428

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

PubMed

We find limiting distributions of the nonparametric maximum likelihood estimator (MLE) of a log-concave density, i.e. a density of the form f(0) = exp varphi(0) where varphi(0) is a concave function on R. Existence, form, characterizations and uniform rates of convergence of the MLE are given by Rufibach (2006) and Dmbgen 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, infinity) 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 H(k), the "lower invelope" of an integrated Brownian motion process minus a drift term depending on the number of vanishing derivatives of varphi(0) = log f(0) at the point of interest. We also establish the limiting distribution of the resulting estimator of the mode M(f(0)) 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. PMID:19881896

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

2009-06-01

429

Development of geothermal logging systems in the United States  

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 on-board 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) is in the calibration phase, and it is expandable into all nuclear measurements common in the hydrocarbon industry. A fluid sampling tool is in the design phase. All tools are designed for operation at conditions exceeding 400 C, and for deployment in the slim holes produced by mining-coring operations. Partnerships are being formed between the geothermal industry and scientific drilling programs to define and develop inversion algorithms relating raw tool data to more pertinent information. These cooperative efforts depend upon quality guidelines such as those under development within the international Ocean Drilling Program.

Lysne, P.

1994-04-01

430

A receiving array of log-periodic dipoles  

NASA Astrophysics Data System (ADS)

The mutual impedance of dipoles for a modified vertical log-periodic dipole antenna is analyzed with allowance for mutual coupling effects. Formulas are presented for calculating the radiation pattern and impedance for an antenna array above the ground system. It is shown that the arrays performed relatively well over a 4.3:1 bandwidth while being phase-scanned over an azimuth range of + or - 45 deg.

Yang, Rongxi; Huang, Chibiao; Xia, Lianrong

431

Breaking the vicious circle of illegal logging in Indonesia.  

PubMed

The government of Indonesia, which presides over 10% of the world's tropical forests, has set ambitious targets to cut its high deforestation rates through an REDD+ scheme (Reducing Emissions from Deforestation and forest Degradation). This will require strong law enforcement to succeed. Yet, strategies that have accomplished this are rare and, along with past failures, tend not to be documented. We evaluated a multistakeholder approach that seeks to tackle illegal logging in the carbon-rich province of Aceh, Sumatra. From 2008 to 2009, Fauna & Flora International established and supported a community-based informant network for the 738,000 ha Ulu Masen ecosystem. The network reported 190 forest offenses to local law enforcement agencies, which responded with 86 field operations that confiscated illicit vehicles, equipment, and timber, and arrested 138 illegal logging suspects. From 45 cases subsequently monitored, 64.4% proceeded to court, from which 90.0% of defendants received a prison sentence or a verbal warning for a first offense. Spatial analyses of illegal logging and timber storage incidents predicted that illegal activities would be more effectively deterred by law enforcement operations that targeted the storage sites. Although numerous clusters of incidents were identified, they were still widespread reflecting the ubiquity of illegal activities. The multistakeholder results were promising, but illegal logging still persisted at apparently similar levels at the project's end, indicating that efforts need to be further strengthened. Nevertheless, several actions contributed to the law enforcement achievements: strong political will; strong stakeholder support; and funding that could be promptly accessed. These factors are highlighted as prerequisites for achieving Indonesia's ambitious REDD+ goals. PMID:24628366

Linkie, Matthew; Sloan, Sean; Kasia, Rahmad; Kiswayadi, Dedy; Azmi, Wahdi

2014-08-01

432

Theoretical analysis of a log-periodic structure  

Microsoft Academic Search

An analysis of a two-dimensional log-periodic corrugated plane is presented as a perturbation series. The zero-order solution is that for which the structure is embedded in a medium of continuously variable refractive index, such that in a coordinate system in which the boundaries become periodic, the wave equation also admits a periodic solution. The solution in an actual physical medium,

D. Varon; R. Kieburtz

1964-01-01

433

Microstrip log-periodic antenna array with endfire beam  

Microsoft Academic Search

Endfire action with a very wide-bandwidth, low-profile antenna array has not yet been achieved. After showing that a conventional microstrip log-periodic array cannot be successfully scanned from broadside to endfire, a new configuration involving quarter-wavelength shorted patches is described. First-order theory indicates that good endfire action should be possible, and this is confirmed by preliminary measurements on an array designed

P. S. Hall; A. Sparrow

1987-01-01

434

Visualizing the log-periodic pattern before crashes  

Microsoft Academic Search

: We present a method for visualizing the pattern which we believe to be a precursor signature of financial crashes (or ruptures).\\u000a The log-periodicity of the pattern is investigated through the envelope function technique. Three periods of the Dow Jones\\u000a Industrial Average (DJIA) are investigated: 1982-1987, 1992-1997 and 1993-1998. The presence of a rupture in the end of 1998\\u000a is

N. Vandewalle; M. Ausloos; Ph. Boveroux; A. Minguet

1999-01-01

435

Comments on the design of log-periodic dipole antennas  

Microsoft Academic Search

The design procedure of the log-periodic dipole (LPD) antennas is discussed. The results of the calculations carried out by the use of the more recent and accurate methods of the analysis for the arrays of unequal dipoles, are compared with those already available in the literature. The calculations refer to the gain of LPD antenna as a function ofZ_{0}, the

GIUSEPPE DE VITO; GIOVANNI B. STRACCA

1973-01-01

436

Study of compressed log-periodic dipole antennas  

Microsoft Academic Search

The behavior of log-periodic dipole (LPD) antennas, which are compressed along the transmission-line axis, is studied both experimentally and theoretically. Compressed LPD antennas are found to be efficient, of low gain, and frequency independent. With compression, the radiation pattern approaches dipole-like behavior and the bandwidth increases slightly. It is also found that LPD antennas exhibit anomalous frequency-dependent behavior in narrow

C. Bantin; K. Balmain

1970-01-01

437

Daily Crime Log Query Date: 6/15/2014  

E-print Network

Daily Crime Log Query Date: 6/15/2014 6/13/2014 9:46:54PM 14-1313 Juvenile Proble Parents requested assistance with their 17-year-old juvenile daughter. ACT 50 N Mario Capecchi Dr; B529 - ECCP Narrative: Disposition: Citizen AssistOffense: 6/13/2014 9:46:54PM 14-1313 Juvenile Proble Parents requested assistance

Tipple, Brett

438

Evaluation of log-transformation in assessing bioequivalence  

Microsoft Academic Search

The question of whether we should use log-transformed data in assessing bioequivalence between two formulations is studied through a simulation. Under a 22 cross-over design with different combinations of sample size and intrasubject variability, we examine the impacts of different scales of the data on the conclusion of bioequivalence as well as on the level of significance and power. We

Jen-Pei Liu; Chung-Sing Weng

1994-01-01

439

Adaptive Power Spectrum Method for Processing Full Waveform Logs  

NASA Astrophysics Data System (ADS)

The power spectra of borehole mode waves like compressional and shear head waves and Stoneley waves etc., are very important information from full wave acoustic logging data analysis. Conventional power spectrum analysis based on Fourier transform cannot derive such detailed power spectra because of none resolution in time domain. We have developed a new power spectrum analysis technique for full waveform acoustic array logs. Based on local cosine packet analysis and K-L transformation, this technique can diagonalize the correlation matrix of the acoustic signal. Meanwhile for the local stationary signal, the local cosine base is the best candidate of K-L transformation base. After the correlation matrix is diagonalized, the elements at diagonal represent the power spectrum of the signal. By arranging this procedure into an optimization procedure, we can thus determine the time window for each mode adaptively while calculating each individual power spectrum at the same time. The first step of the data processing algorithm is to decompose the whole signal with local cosine packet. And then the power spectrum of each component is calculated. Finally, we will find the optimum base with the local cosine packet tree. The objective function of the optimization is composed of the norm-2 of the power under certain base. Because the full waveform of acoustic logging is not an exact local stationary signal, the compressional and shear head waves are correlated. Therefore the STC method is employed to get the arrival time of compressional and shear head waves from the array waveform data, and then the shear arrival time can be taken as a constraint for this optimization. We have applied this method to a set of field full waveform logs. Our results have shown that the individual borehole modes are separated correctly and the power spectra for each mode agree with the existing theoretical predictions.

He, F.; Tao, G.

2005-05-01

440

Secure Logging of Retained Data for an Anonymity Service  

Microsoft Academic Search

\\u000a The recently introduced legislation on data retention to aid prosecuting cyber-related crime in Europe also affects the achievable\\u000a security of systems for anonymous communication on the Internet. We have analyzed the newly arising risks associated with\\u000a the process of accessing and storage of the retained data and propose a secure logging system, which utilizes cryptographic\\u000a smart cards, trusted timestamping servers

Stefan Kpsell; Petr venda

441

88. Groundhog Mountain. View of the log fire lookout constructed ...  

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

88. Groundhog Mountain. View of the log fire lookout constructed by the Virginia State Forest service in the summer of 1942. A buck or Yankee fence crosses the foreground with a snake fence in the background. Civilian public service employees began erecting the rail fences in April 1939. Looking north-northeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

442

Value of Travel Time.  

National Technical Information Service (NTIS)

The Record includes 6 papers covering important areas of travel time value analysis, such as travel time value theory, conceptual problems in travel time value, methods of deriving travel time values, review of empirical travel time value studies, applica...

R. Gronau

1976-01-01

443

Characterizing Application Runtime Behavior from System Logs and Metrics  

SciTech Connect

Large-scale systems are heavily shared resource environments where a mix of applications are launched concurrently competing for network and storage resources. It is essential to characterize the runtime behavior of these applications for provisioning system resources and understanding the impact of application s performance when competing for resources. In this paper, we study the use of zero- and low-overhead system logs and other system metric data for characterizing the runtime behavior of several applications. We present our preliminary work on estimating individual application s I/O demands by observing file system usage pattern over multiple runs, and interpreting application s network utilization characteristics by observing link-layer error logs. We also present preliminary findings on using such information in making context-sensitive scheduling decisions that minimize potentially negative interactions between applications competing for shared resources. Our analysis is based on four months of system log data collected on one of the world s largest supercomputing facilities, the Jaguar XT5 petaflop system at Oak Ridge National Laboratory.

Gunasekaran, Raghul [ORNL] [ORNL; Dillow, David A [ORNL] [ORNL; Shipman, Galen M [ORNL] [ORNL; Vuduc, Richard [Georgia Institute of Technology] [Georgia Institute of Technology; Chow, Edmond [Georgia Institute of Technology] [Georgia Institute of Technology

2011-01-01

444

On Efficient Confidence Intervals for the Log-Normal Mean  

NASA Astrophysics Data System (ADS)

Data obtained in biomedical research is often skewed. Examples include the incubation period of diseases like HIV/AIDS and the survival times of cancer patients. Such data, especially when they are positive and skewed, is often modeled by the log-normal distribution. If this model holds, then the log transformation produces a normal distribution. We consider the problem of constructing confidence intervals for the mean of the log-normal distribution. Several methods for doing this are known, including at least one estimator that performed better than Coxxs method for small sample sizes. We also construct a modified version of Coxxs method. Using simulation, we show that, when the sample size exceeds 30, it leads to confidence intervals that have good overall properties and are better than Coxxs method. More precisely, the actual coverage probability of our method is closer to the nominal coverage probability than is the case with Coxxs method. In addition, the new method is computationally much simpler than other well-known methods.

Chami, Peter; Antoine, Robin; Sahai, Ashok

445

Instant well-log inversion with a parallel computer  

SciTech Connect

Well-log analysis requires several vectors of input data to be inverted with a physical model that produces more vectors of output data. The problem is inherently suited to either vectorization or parallelization. PLATO (parallel log analysis, timely output) is a research prototype system that uses a parallel architecture computer with memory-mapped graphics to invert vector data and display the result rapidly. By combining this high-performance computing and display system with a graphical user interface, the analyst can interact with the system in real time'' and can visualize the result of changing parameters on up to 1,000 levels of computed volumes and reconstructed logs. It is expected that such instant'' inversion will remove the main disadvantages frequently cited for simultaneous analysis methods, namely difficulty in assessing sensitivity to different parameters and slow output response. Although the prototype system uses highly specific features of a parallel processor, a subsequent version has been implemented on a conventional (Serial) workstation with less performance but adequate functionality to preserve the apparently instant response. PLATO demonstrates the feasibility of petroleum computing applications combining an intuitive graphical interface, high-performance computing of physical models, and real-time output graphics.

Kimminau, S.J.; Trivedi, H.

1993-08-01

446

Leveraging Call Center Logs for Customer Behavior Prediction  

NASA Astrophysics Data System (ADS)

Most major businesses use business process outsourcing for performing a process or a part of a process including financial services like mortgage processing, loan origination, finance and accounting and transaction processing. Call centers are used for the purpose of receiving and transmitting a large volume of requests through outbound and inbound calls to customers on behalf of a business. In this paper we deal specifically with the call centers notes from banks. Banks as financial institutions provide loans to non-financial businesses and individuals. Their call centers act as the nuclei of their client service operations and log the transactions between the customer and the bank. This crucial conversation or information can be exploited for predicting a customers behavior which will in turn help these businesses to decide on the next action to be taken. Thus the banks save considerable time and effort in tracking delinquent customers to ensure minimum subsequent defaulters. Majority of the time the call center notes are very concise and brief and often the notes are misspelled and use many domain specific acronyms. In this paper we introduce a novel domain specific spelling correction algorithm which corrects the misspelled words in the call center logs to meaningful ones. We also discuss a procedure that builds the behavioral history sequences for the customers by categorizing the logs into one of the predefined behavioral states. We then describe a pattern based predictive algorithm that uses temporal behavioral patterns mined from these sequences to predict the customers next behavioral state.

Parvathy, Anju G.; Vasudevan, Bintu G.; Kumar, Abhishek; Balakrishnan, Rajesh

447

Application of Nuclear Well Logging Techniques to Lunar Resource Assessment  

NASA Technical Reports Server (NTRS)

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 purpose has developed neutron generators that allow measurements to be made in deep (5000 m) boreholes under adverse conditions. We also make ruggedized neutron and gamma ray detector packages that can be used to make reliable measurements on the drill collar of a rotating drill string while the well is being drilled, where the conditions are severe. Modern nuclear methods used in logging measure rock formation parameters like bulk density and porosity, fluid composition, and element abundances by weight including hydrogen concentration. The measurements are made with high precision and accuracy. These devices (well logging sondes) share many of the design criteria required for remote sensing in space; they must be small, light, rugged, and able to perform reliably under adverse conditions. We see a role for the adaptation of this technology to lunar or planetary resource assessment missions.

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

1992-01-01

448

Unveiling ALMA software behavior using a decoupled log analysis framework  

NASA Astrophysics Data System (ADS)

ALMA Software is a complex distributed system installed in more than one hundred of computers, which interacts with more than one thousand of hardware device components. A normal observation follows a flow that interacts with almost that entire infrastructure in a coordinated way. The Software Operation Support team (SOFTOPS) comprises specialized engineers, which analyze the generated software log messages in daily basis to detect bugs, failures and predict eventual failures. These log message can reach up to 30 GB per day. We describe a decoupled and non-intrusive log analysis framework and implemented tools to identify well known problems, measure times taken by specific tasks and detect abnormal behaviors in the system in order to alert the engineers to take corrective actions. The main advantage of this approach among others is that the analysis itself does not interfere with the performance of the production system, allowing to run multiple analyzers in parallel. In this paper we'll describe the selected framework and show the result of some of the implemented tools.

Gil, Juan Pablo; Tejeda, Alexis; Shen, Tzu-Chiang; Saez, Norman

2014-07-01

449

Density of the Values Set of the Tau Function  

E-print Network

It is shown that the density of the values set {Tau(n): n > x/log x. The currently known density is #{Tau(n) : n > x^(1/2+o(1)), and the expected density is #{Tau(n) : n 2, which arises as a singular case of this analysis, is discussed within.

N. A. Carella

2014-04-10

450

Geophysical logs and core measurements from forty boreholes at Yucca Mountain, Nevada  

SciTech Connect

A data base of geophysical logs and core measurements acquired in boreholes at Yucca Mountain, Nevada, has been established. We used this data set to generate log plots from 40 boreholes at a scale of 1:1200 for reference and for correlation. Log headers summarize the drilling and logging sequence. We describe the logging tools, the sources of core data, and the editing procedures. We illustrate the adverse effects of casing on the gamma-ray log, of borehole rugosity on the density log, and of borehole diameter and fluid resistivity on the resistivity logs. Welding and alteration of the tuffs are the dominant geological controls on the response of the density, velocity, neutron, and resistivity logs. Density, resistivity, gamma-ray, and, in particular, the magnetic-field logs are useful for correlation of stratigraphy and alteration. A few zones in which the matrix is moderately permeable have produced log responses indication invasion of the rock by drilling fluid. Readings from the density log were confirmed with core measurements. It appears that the epithermal-neutron and dielectric-permittivity logs can be used to estimate water content providing calibration methods are established. 82 refs., 30 figs., 6 tabs.

Nelson, P.H.; Muller, D.C.; Schimschal, U.; Kibler, J.E.

1991-11-01

451

Possibilities of three-component geoacoustic logging at hydrocarbon deposits.  

NASA Astrophysics Data System (ADS)

The geophysical method of oil-gas borehole investigation devised at the Institute of geophysics UB of RAS studies characteristics of geoacoustic emission (GAE) over the frequency range of 0.15 kHz which displays peculiarities of fluid-gas dynamic processes in a volume of geological environment. More over: 1. The second displacement derivative (acceleration) of borehole walls' vibrations is recorded. 2. The three-component system of orthogonal transducers-accelerometers in a protecting casing of a borehole instrument with the diameter of 40-42 mm enabling to divide geoenvironment microvibrations into three directions is applied. 3. Frequency composition of recorded geoacoustic signals is analyzed. 4. Values of measured and calculated parameters representing distribution of signal amplitudes according to three components at four frequency bands are evaluated. Three-component geoacoustic logging at hydrocarbon deposits solves the following problems: Estimation of fluid saturation character at a qualitative level; Detection of fluid flow outside and inside the casing string with division into fluid types; Detection of fluid flow position in chambers of a cement ring with division into fluid types; Detection of non-sealed points of borehole equipment; Location of gas-water, gas-oil ad water-oil contacts; Study of inflow section in a perforated interval of casing string which determines the boundaries of efficient intervals; Detection of sections with high absorption of drilling fluid in an open shaft; Test for leaks of the column (together with thermometry); Detection of intervals of fluid movement in horizontal direction outside a casing string within seams (it is impossible to determine them by other methods); Detection of industrial deposits; Revelation of water-flooded intervals of a hydrocarbon deposit. Transducers-accelerometers with relative coefficient of transverse conversion not more than 6% allow confident division of signals into three directions. Transverse sensitivity of a transducer is determined by its maximum sensitivity to oscillations in a direction perpendicular to its main axis that is parallel to the surface where it is placed. The equipment [1] has sensitivity that enables to record an acoustic response of geoenvironment to deformations in the order of 10-8 - 10-11 m. Geoacoustic signals in sedimentary rocks are recorded by three orthogonal transducers-accelerometers of PVT type (piezoelectric vibromeasuring transducer). Transducers with coefficients of conversion not less than 6-10 V*s2/mm are installed into a borehole instrument. Amplitude level of signals at different frequency bands is presented in units of recorded acceleration mm/s2. Small amplitude of geoenvironment microvibrations is an additional optimum condition to divide signals from three directions. Thus, signals from three directions are fixed at preset depth in a borehole which makes it possible to compare their amplitude at different frequency bands. References: 1. Yu. G. Astrakhantsev and A. K. Troyanov, RF Patent No. 2 445 653, 2012.

Trojanov, Alexandr; Astrakhantsev, Yurie; Nachapkin, Nikolay; Beloglasova, Nadejda; Bajenova, Evgenia; Vdovin, Alexey

2013-04-01

452

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

Code of Federal Regulations, 2010 CFR

...2010-10-01 false What are the rules for securing logs? 393.116 Section 393.116 Transportation Other Regulations Relating...Specific Securement Requirements by Commodity Type 393.116 What are the rules for securing logs?...

2010-10-01

453

Geophysical Well-Log Analysis In Characterizing The Hydrology Of Crystalline Rocks Of The Canadian Shield  

E-print Network

A full suite of geophysical logs, including nuclear, electric, acoustic transit-time, acoustic waveform, and acoustic televiewer logs, and high-resolution flowmeter measurements have been used to investigate the lithologic ...

Paillet, F . L.

1988-01-01

454

MATHEMATICS AND SCIENCE CENTERS STUDENT SERVICES ACTIVITY LOG/EVENT RECORD  

E-print Network

MATHEMATICS AND SCIENCE CENTERS STUDENT SERVICES ACTIVITY LOG/EVENT RECORD Use this log for all. ENROLLEES BY TYPE: (Check one) ______ GENDER: ETHNICITY: ___ Mathematics ____ Female ___ African ___ No ___ Mathematics ___ Science ___ Technology ___ Other Describe: ____________________ 12. DESCRIPTION: (Purpose

455

Software Issues in Characterizing Web Server Logs Balachander Krishnamurthy and Jennifer Rexford  

E-print Network

Software Issues in Characterizing Web Server Logs Balachander Krishnamurthy and Jennifer Rexford AT. These logs range in durations from a day, to a few weeks, to several months. The number of hits on sites vary

Singh, Jaswinder Pal

456

Design of Circular Log-Periodic Arrays Using Electromagnetic Simulations Ozgur Ergul and Levent Gurel*  

E-print Network

Design of Circular Log-Periodic Arrays Using Electromagnetic Simulations ¨Ozg¨ur Erg¨ul and Levent of circular arrays of log-periodic (LP) antennas by taking advan- tage of a powerful electromagnetic

Gürel, Levent

457

Nuclear Magnetic Resonance (NMR) is the only logging technique available to estimate pore-size  

E-print Network

1 ABSTRACT Nuclear Magnetic Resonance (NMR) is the only logging technique available to estimate, Nuclear Magnetic Resonance (NMR) logging has been used to assess a handful of key petrophysical parameters

Torres-Verdín, Carlos

458

36 CFR 1254.12 - Will NARA log or inspect my computer, other equipment, and notes?  

Code of Federal Regulations, 2011 CFR

...false Will NARA log or inspect my computer, other equipment, and notes? 1254...12 Will NARA log or inspect my computer, other equipment, and notes? (a) If you bring personal computers, scanners, tape recorders,...

2011-07-01

459

36 CFR 1254.12 - Will NARA log or inspect my computer, other equipment, and notes?  

Code of Federal Regulations, 2010 CFR

...false Will NARA log or inspect my computer, other equipment, and notes? 1254...12 Will NARA log or inspect my computer, other equipment, and notes? (a) If you bring personal computers, scanners, tape recorders,...

2010-07-01

460

36 CFR 1254.12 - Will NARA log or inspect my computer, other equipment, and notes?  

Code of Federal Regulations, 2012 CFR

...false Will NARA log or inspect my computer, other equipment, and notes? 1254...12 Will NARA log or inspect my computer, other equipment, and notes? (a) If you bring personal computers, scanners, tape recorders,...

2012-07-01

461

36 CFR 1254.12 - Will NARA log or inspect my computer, other equipment, and notes?  

...false Will NARA log or inspect my computer, other equipment, and notes? 1254...12 Will NARA log or inspect my computer, other equipment, and notes? (a) If you bring personal computers, scanners, tape recorders,...

2014-07-01

462

36 CFR 1254.12 - Will NARA log or inspect my computer, other equipment, and notes?  

Code of Federal Regulations, 2013 CFR

... true Will NARA log or inspect my computer, other equipment, and notes? 1254...12 Will NARA log or inspect my computer, other equipment, and notes? (a) If you bring personal computers, scanners, tape recorders,...

2013-07-01

463

Low-frequency P-wave logging for improved compressional velocity in slow formation gas zones  

SciTech Connect

The ratio of compressional to shear velocity is commonly used as a gas indicator, for seismic correlation, and for rock mechanical properties evaluation in the oil industry. However, in soft rock gas zone, it is difficult to obtain a good measure of compressional velocity. Traditional monopole sonic logging tools operate with source frequencies above 10 kHz, giving rise to large amplitude borehole fluid modes which dominate compressional wave traveling with speed slower than the fluid speed. Numerical modeling of monopole sonic waveforms in a fluid-filled borehole in porous formations confirms these observations, but also shows that at significantly lower frequencies two important changes occur: (1) the non-Stoneley fluid modes becomes extremely small, and (2) the P-wave amplitude is greatly increased. Therefore, at low frequencies, logging of these very slow P-waves in gas zones should be feasible. A field example shows the value of this low frequency technique, resulting in measurements of P-wave velocities substantially lower than the fluid speed.

Wu, P.T.; Darling, H.L.; Scheibner, D.

1995-12-31

464

The Allometry of Coarse Root Biomass: Log-Transformed Linear Regression or Nonlinear Regression?  

PubMed Central

Precise estimation of root biomass is important for understanding carbon stocks and dynamics in forests. Traditionally, biomass estimates are based on allometric scaling relationships between stem diameter and coarse root biomass calculated using linear regression (LR) on log-transformed data. Recently, it has been suggested that nonlinear regression (NLR) is a preferable fitting method for scaling relationships. But while this claim has been contested on both theoretical and empirical grounds, and statistical methods have been developed to aid in choosing between the two methods in particular cases, few studies have examined the ramifications of erroneously applying NLR. Here, we use direct measurements of 159 trees belonging to three locally dominant species in east China to compare the LR and NLR models of diameter-root biomass allometry. We then contrast model predictions by estimating stand coarse root biomass based on census data from the nearby 24-ha Gutianshan forest plot and by testing the ability of the models to predict known root biomass values measured on multiple tropical species at the Pasoh Forest Reserve in Malaysia. Based on likelihood estimates for model error distributions, as well as the accuracy of extrapolative predictions, we find that LR on log-transformed data is superior to NLR for fitting diameter-root biomass scaling models. More importantly, inappropriately using NLR leads to grossly inaccurate stand biomass estimates, especially for stands dominated by smaller trees. PMID:24116197

Lai, Jiangshan; Yang, Bo; Lin, Dunmei; Kerkhoff, Andrew J.; Ma, Keping

2013-01-01

465

Evaluation of Non-Nuclear Techniques for Well Logging: Technology Evaluation  

SciTech Connect

This report presents an initial review of the state-of-the-art nuclear and non-nuclear well logging methods and seeks to understand the technical and economic issues if AmBe, and potentially other isotope sources, are reduced or even eliminated in the oil-field services industry. Prior to considering alternative logging technologies, there is a definite need to open up discussions with industry regarding the feasibility and acceptability of source replacement. Industry views appear to range from those who see AmBe as vital and irreplaceable to those who believe that, with research and investment, it may be possible to transition to electronic neutron sources and employ combinations of non-nuclear technologies to acquire the desired petro-physical parameters. In one sense, the simple answer to the question as to whether petro-physical parameters can be sensed with technologies other than AmBe is probably "Yes". The challenges come when attention turns to record interpretation. The many decades of existing records form a very valuable proprietary resource, and the interpretation of subtle features contained in these records are of significant value to the oil-gas exploration community to correctly characterize a well. The demonstration of equivalence and correspondence/correlation between established and any new sensing modality, and correlations with historic records is critical to ensuring accurate data interpretation. Establishing the technical basis for such a demonstration represents a significant effort.

Bond, Leonard J.; Denslow, Kayte M.; Griffin, Jeffrey W.; Dale, Gregory E.; Harris, Robert V.; Moran, Traci L.; Sheen, David M.; Schenkel, Thomas

2010-11-01

466

Effect of Various Sawdusts and Logs Media on the Fruiting Body Formation of Phellinus gilvus  

PubMed Central

Present experiments were conducted to determine the possibility of artificial culture with various sawdust of P. gilvus. The pH value was 6.0 of oak sawdust, 6.5 of mulberry sawdust, 6.6 of elm sawdust, 6.3 of acacia sawdust and 6.1 of apple tree sawdust. Mycelial density on elm sawdust and acacia sawdust were lower than those of oak sawdust, and apple sawdust. Weight of fresh fruiting body showed that 179 g on oak tree, 227 g on oak sawdust, 21 g on elm tree, 76 g on elm sawdust, 106 g on apple tree, and 170 g on apple sawdust. Among them, the yield of oak substrates was the highest whereas acacia sawdust was the lowest, and it is concluded that the yields of sawdust substrates were higher than log substrates. P. gilvus grown on various sawdusts and logs used in this study have shown similar in anti-tumor activity against P388. PMID:24015060

Rew, Young-Hyun; Choi, Sung-Guk; Hwang, Mi-Hyun; Park, Seung-Chun; Seo, Geon-Sik; Sung, Jae-Mo; Uhm, Jae-Youl

2007-01-01

467

Correlation of hydrotropic solubilization by urea with logD of drug molecules and utilization of this effect for topical formulations.  

PubMed

Solubilization of drugs in aqueous phases of liquid and semisolid environment is typically achieved by co-solvents or surfactants. On contrast, solubilization by means of hydrotropic agents, i.e., small hydrophilic organic compounds like urea or citric acid, is little explored in the context of pharmaceutical formulations. Especially, with regard to topical dosage forms, however, hydrotropic solubilization can provide valuable alternatives to establish solubilization approaches. A difficulty of employing hydrotropic solubilization was that its extent could not be predicted for different drug molecules. Using a chemically heterogeneous set of 12 compounds relevant for dermatology (with overall 16 different logD values tested), we were able to demonstrate that hydrotropic effects of urea can be predicted by logD values of drugs. All compounds with logD values between 2 and 4.5 showed a solubility enhancement factor (EF) of >5 in 40% aqueous solutions of urea. For logD values below 2 or above 5, only EF<5 were found. For some compounds, e.g., diclofenac (pH 4) and prednicarbate could achieved only EF>5 at 5% urea and EF>250 at 20% urea. PMID:23958327

Herbig, Michael E; Evers, Dirk-Heinrich

2013-09-01

468

Chemical changes and carbon isotope variations in a cross-section of a large Miocene gymnospermous log  

USGS Publications Warehouse

The cross-sectional radius of a 3-m (diam.) brown coal gymnospermous log of Miocene age, previously analyzed for carbohydrate and lignin methoxyl content by solid-state 13C nuclear magnetic resonance spectroscopy, was examined using stable carbon isotopic ratios in order to determine if the isotopic composition could be related to chemical changes or to radial position. This study found a possible relationship between ??13C-values and radial position; however, these changes cannot be linked to carbohydrate content and are probably attributable to changing growth conditions during the lifetime of the tree. An apparent linear relationship between the changes in carbohydrate content after sodium para-periodate treatment and corresponding changes in the ??13C-values indicates constant isotopic fractionation between lignin and carbohydrates along the cross-sectional radius. This result indicates that diagenesis has not produced any significant change in the lignin-carbohydrate carbon isotopic fractionation or, alternatively, that diagenesis has erased any fractionation pattern that once existed. A sample of fresh wood from another gymnospermous species was analyzed by the same methods and found to have lignin-carbohydrate carbon isotopic fractionation significantly different from that of the Miocene log section samples, suggesting that differences may be species-related or that the complex mixture of carbohydrates in the fresh wood was isotopically different from that of the degraded wood, and the whole Miocene log was uniformly altered. ?? 1992.

Bates, A.L.; Spiker, E.C.

1992-01-01

469

Upper-crustal scattering parameters as derived from induced micro-seismicity and acoustic log data  

NASA Astrophysics Data System (ADS)

In deterministic seismology it is assumed, that each inhomogeneity within the traversed medium causes a travel time shift and/or special phase in the observed seismogram. This information may then be used to analyze the properties of the inhomogeneity (e.g. location, size). However, this method is only successful for inhomogeneities larger than the station separation, the Fresnel zone and the wavelength. In the Earth's curst there exist many small-scale heterogeneities. Stochastic models can be used to determine the most important statistical parameters of the small-scale inhomogeneities neglecting their exact locations. In high-frequency seismograms (> 1 Hz) information on heterogeneity and seismic absorption is reflected by wave trains following the direct wave featuring decreasing amplitude with increasing lapse time, know as Coda waves. Since seismic wave propagation through a heterogeneous and absorbing medium is an extremely complex process, it has become common practice to use seismogram envelopes instead of complete waveforms to gain insight in the attenuation properties. Besides the manifestation in high-frequency seismograms information on heterogeneity can be extracted from well-logs. Borehole measurements provide detailed 1D information on the distribution of elastic properties within the upper crust at scales from about one meter to several kilometers. Strong random fluctuations in seismic velocity having short wavelengths superposed on a step-like structure represent here the deterministic and stochastic components of the crustal structure. These observations suggest a description of the crust as a random medium with a broad spectrum of heterogeneity. In the framework of developing techniques for the estimation of attenuation properties in geothermal reservoirs, as part of the German research program Geothermal Energy and High-performance Drilling (gebo), seismogram envelope inversion and statistical analysis of acoustic logs have been applied to data from the German Continental Deep Drilling (KTB) project. In the present research a passive seismic data set is considered which was acquired during a long-term hydraulic fracturing treatment at the KTB in 2000. Induced seismicity was recorded with a temporal seismic network, consisting of 40 stations, at epicentral distances less than 20 km. Processed seismic events have magnitudes Ml 1.0. Acoustic log data comprise the P- and S-wave velocity distribution logged in two boreholes. In the pilot borehole continuous data reach from the surface (28 m) to a depth of approx. 4000 m, while for the main borehole coherent logs are available between 285 m and 7160 m. Scattering and intrinsic attenuation, derived from micro-seismic events at the KTB, reasonably match regional attenuation models for Southern Germany. In contrast, scattering strength estimated from acoustic log data exceeds the regional attenuation models by one order of magnitude. The scattering coefficient shows weak but almost identical frequency dependence for both types of analysis that is best-described by a power-law form. From the frequency dependence it can be inferred that a von Krmn-type of random medium is a good model for representing the fractured geothermal reservoir at the KTB. The estimated Hurst exponent, related to the scattering coefficient, is also in good agreement with reference values derived for the upper crust.

Fielitz, Daniel; Wegler, Ulrich

2013-04-01

470

The effect of density-driven convection on temperature logs - detection, differentiation and pitfalls  

NASA Astrophysics Data System (ADS)

Density-driven (free) convection can cause significant transport of heat and mass in the water column of boreholes and wells. Consequently, temperatures and concentrations measured in boreholes or monitoring wells may depart significantly from the ones in the surrounding rock. Moreover, density-driven convection can also affect the surrounding rock thermally and geochemically. Understanding convective flow is thus crucial for analyses based on borehole geophysical measurements or sampling campaigns, like hydrogeological and geothermal investigations. In these cases, the water column should be examined according to the occurrence of falsifying effects of vertical transport processes. In a water column several convection-affected sections can exist, that can exhibit different forms of density-driven flows. Some of these density-driven flows lead to equalization (overturning convection) and others to reinforcement of a vertical temperature/density contrast (double-diffusion). By means of the so-called Synthetic Convection Log - a computational algorithm that enables in-situ detection and differentiation of various density-driven transport processes in the water column - it could be shown, that density-driven convection appears widespread in groundwater monitoring wells and boreholes. Numerous measurements in a large number of different survey areas showed, that density-driven convective transport is rather the rule than the exception. In particular, near surface zones of the water column are significantly affected by the high temperature gradients in the shallow subsoil. Deep groundwater monitoring wells and boreholes with a seasonally constant geothermally induced temperature gradient are often likewise affected, due to the considerably low threshold for the onset of the convection. The induced flow velocities are in the order of several meters per day and increase with temperature/density gradient. The convective flow velocity in wells or boreholes can consequently exceed the velocity of the horizontal natural groundwater (through) flow. Density-driven convection causes anomalies and patterns in temperature and water quality logs. These include e.g., stratification and staircase structures or oscillations caused by convection cells. Overturning thermal, solutale or thermosolutale convection leads to spatially and temporarily oscillations in the otherwise smooth temperature log. The affected water column acts as a mixing reactor. Due to the high velocity of the revolving convection, this mixing is very effective. The so-called double-diffusion is accompanied by the formation of typical step structures in temperature logs which originate from the change from convective to well mixed layers with intervening diffusive transitional layers. The layers of convective transport are characterized by relatively steady values and the layers by diffusive transport are characterized by jump-like changes in temperature, forming the staircase structures. These anomalies and patterns can be qualitatively evaluated (e.g., by the Synthetic Convection Log) to assess falsifying effects on temperature logs due to mixture, heat and mass transport.

Berthold, Susann

2013-04-01

471

Ethanol and Ambrosia Beetles in Douglas Fir Logs Exposed or Protected from Rain  

Microsoft Academic Search

Logs from the base of Douglas fir (Pseudotsuga menziesii) trees cut in October 1993 were randomly assigned to one of three treatment groups: (1) wet logscut from the fallen tree and left exposed to rain, (2) dry logscut from the fallen tree, placed on blocks, and protected from rain under a plastic tent, and (3) crown logsleft attached to the

Rick G. Kelsey; Gladwin Joseph

1999-01-01

472

Drumming Log Habitat Selection by Male Ruffed Grouse in North Carolina  

Microsoft Academic Search

Abstract: We evaluated ,ruffed grouse Bonasa umbellus,drumming ,logs in western North Carolina to determine criteria used by male grouse in selecting drumming,sites. For every drumming log found (N = 34), we selected a random log within the same stand type and with a similar topographic position. Wecollected data on drumming log characteristics and on vegetation surrounding the drumming,site. Wefound,85% (N

Gordon S. Warburton

473

Two-stage recovery of amphibian assemblages following selective logging of tropical forests.  

PubMed

There is a lack of quantitative information on the effectiveness of selective-logging practices in ameliorating effects of logging on faunal communities. We conducted a large-scale replicated field study in 3 selectively logged moist semideciduous forests in West Africa at varying times after timber extraction to assess post logging effects on amphibian assemblages. Specifically, we assessed whether the diversity, abundance, and assemblage composition of amphibians changed over time for forest-dependent species and those tolerant of forest disturbance. In 2009, we sampled amphibians in 3 forests (total of 48 study plots, each 2 ha) in southwestern Ghana. In each forest, we established plots in undisturbed forest, recently logged forest, and forest logged 10 and 20 years previously. Logging intensity was constant across sites with 3 trees/ha removed. Recently logged forests supported substantially more species than unlogged forests. This was due to an influx of disturbance-tolerant species after logging. Simultaneously Simpson's index decreased, with increased in dominance of a few species. As time since logging increased richness of disturbance-tolerant species decreased until 10 years after logging when their composition was indistinguishable from unlogged forests. Simpson's index increased with time since logging and was indistinguishable from unlogged forest 20 years after logging. Forest specialists decreased after logging and recovered slowly. However, after 20 years amphibian assemblages had returned to a state indistinguishable from that of undisturbed forest in both abundance and composition. These results demonstrate that even with low-intensity logging (?3 trees/ha) a minimum 20-year rotation of logging is required for effective conservation of amphibian assemblages in moist semideciduous forests. Furthermore, remnant patches of intact forests retained in the landscape and the presence of permanent brooks may aid in the effective recovery of amphibian assemblages. PMID:23282143

Adum, Gilbert Baase; Eichhorn, Markus Peter; Oduro, William; Ofori-Boateng, Caleb; Rdel, Mark-Oliver

2013-04-01

474

Effects of salvage logging on avian nest survival in beetle-killed forests  

Microsoft Academic Search

Information about the immediate and potentially prolonged impacts of salvage logging is needed to develop prescriptions that maintain forest productivity, reduce the risk of catastrophic fires, and conserve biological communities. Most salvage logging studies have investigated post-fire salvage, often clearcutting, and impacts documented in these studies may be more severe than selective logging prescriptions applied to forests affected by beetle

Andrew J. Kroll; Edward B. Arnett; Bob Altman

2010-01-01

475

Annual Logging Symposium, June 21-24, 2009 COMMON STRATIGRAPHIC FRAMEWORK TO SIMULATE  

E-print Network

in The Woodlands, Texas, United States, June 21-24, 2009. ABSTRACT We introduce the concept of common stratigraphicSPWLA 50th Annual Logging Symposium, June 21-24, 2009 1 COMMON STRATIGRAPHIC FRAMEWORK TO SIMULATE applicable) of individual layers are populated from logs and/or core-log correlations to construct the static

Torres-Verdín, Carlos

476

EARLY STAGES OF PLANT SUCCESSION FOLLOWING LOGGING AND BURNING IN THE WESTERN CASCADES OF OREGON  

Microsoft Academic Search

Vegetative changes were documented for 7 years on permanent milacre plots located in three clearcut logged units in the western Cascade Mountains of Oregon. Plant cover and composition were observed the year prior to logging the old-growth Pseudotsuga menziesii forest, after logging but before burning, and during each of five growing seasons following broadcast slash burning. Total plant cover was

C. T. DYRNESS

477

Trophic consequences of postfire logging in a wolfungulate system  

Microsoft Academic Search

Controversy surrounds postfire logging, often because of negative effects on snag-dependent wildlife species. Few studies, however, have examined effects on early-seral species that may benefit from postfire logging, nor effects on trophic relationships. We studied the effects of postfire logging on trophic dynamics between wolves (Canis lupus), three ungulate species and ungulate forage biomass during the first 3 years in

M. Hebblewhite; R. H. Munro; E. H. Merrill

2009-01-01

478

More on a statistical analysis of log-periodic precursors to financial crashes  

Microsoft Academic Search

We respond to Sornette and Johansen's criticisms of our findings regarding log-periodic precursors to financial crashes. Included in this paper are discussions of the Sornette-Johansen theoretical paradigm, traditional methods of identifying log-periodic precursors, the behaviour of the first differences of a log-periodic price series and the distribution of drawdowns for a securities price.

James A. Feigenbaum

2001-01-01

479

Rigorous Analysis of Circular Log-Periodic Arrays Using the Multilevel Fast Multipole Algorithm  

E-print Network

Rigorous Analysis of Circular Log-Periodic Arrays Using the Multilevel Fast Multipole Algorithm-mail: ergul@ee.bilkent.edu.tr, lgurel@bilkent.edu.tr Abstract Circular arrays of log-periodic antennas to their broadband characteristics, log-periodic (LP) antennas have attracted considerable interest since

Gürel, Levent

480

Log-Periodic Power Law as a Predictor of Catastrophic Events: A New Mathematical  

E-print Network

Log-Periodic Power Law as a Predictor of Catastrophic Events: A New Mathematical Justification of a catastrophic event, many parame- ters exhibit log-periodic power behavior, with oscillations of increasing to vastly different systems seems to indicate that the log-periodic power behavior is not related

Kreinovich, Vladik

First Page Previous Page 1 2 3 4 5 6 7 8