WorldWideScience

Sample records for selective logging lasts

  1. Selective logging in the Brazilian Amazon.

    Science.gov (United States)

    G. P. Asner; D. E. Knapp; E. N. Broadbent; P. J. C. Oliveira; M Keller; J. N. Silva

    2005-01-01

    Amazon deforestation has been measured by remote sensing for three decades. In comparison, selective logging has been mostly invisible to satellites. We developed a large-scale, high-resolution, automated remote-sensing analysis of selective logging in the top five timber-producing states of the Brazilian Amazon. Logged areas ranged from 12,075 to 19,823 square...

  2. Selective logging and its relation to deforestation

    Science.gov (United States)

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

    2009-01-01

    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 high-impact conventional and often illegal logging...

  3. Timber production in selectively logged tropical forests in South America.

    Science.gov (United States)

    Michael Keller; Gregory P. Asner; Geoffrey Blate; Frank McGlocklin; John Merry; Marielos Peña-Claros; Johan Zweede

    2007-01-01

    Selective logging is an extensive land-use practice in South America. Governments in the region have enacted policies to promote the establishment and maintenance of economically productive and sustainable forest industries.However, both biological and policy constraints threaten to limit the viability of the industry over the long term.Biological constraints, such as...

  4. Monitoring selective logging in western Amazonia with repeat lidar flights

    Science.gov (United States)

    H.E. Andersen; S.E. Reutebuch; R.J. McGaughey; M.V.N. d' Oliveira; M. Keller

    2014-01-01

    The objective of this study was to test the use of repeat flight, airborne laser scanning data (lidar) for estimating changes associated with low-impact selective logging (approx. 10-15 m3 ha−1 = 5-7% of total standing volume harvested) in natural tropical forests in the Western Brazilian Amazon. Specifically, we investigated change in area...

  5. Log-Optimal Portfolio Selection Using the Blackwell Approachability Theorem

    OpenAIRE

    V'yugin, Vladimir

    2014-01-01

    We present a method for constructing the log-optimal portfolio using the well-calibrated forecasts of market values. Dawid's notion of calibration and the Blackwell approachability theorem are used for computing well-calibrated forecasts. We select a portfolio using this "artificial" probability distribution of market values. Our portfolio performs asymptotically at least as well as any stationary portfolio that redistributes the investment at each round using a continuous function of side in...

  6. Long-term Carbon Loss and Recovery Following Selective Logging in Amazon Forests

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Maoyi; Asner, Gregory P.

    2010-09-30

    Amazon deforestation contributes significantly to global carbon (C) emissions. In comparison, the contribution from selective logging to atmospheric CO2 emissions, and its impact on regional C dynamics, is highly uncertain. Using a new geographically-based modeling approach in combination with high resolution remote sensing data from 1999-2002, we estimate that C emissions were 0.04 – 0.05 Pg C yr-1 due to selective logging from a ~2,664,960 km2 region of the Brazilian Amazon. Selective logging was responsible for 15-19% higher carbon emissions than reported from deforestation (clear-cutting) alone. Our simulations indicated that forest carbon lost via selective logging lasts two to three decades following harvest, and that the original live biomass takes up to a century to recover, if the forests are not subsequently cleared. The two- to three-decade loss of carbon results from the biomass damaged by logging activities, including leaves, wood, and roots, estimated to be 89.1 Tg C yr-1 from 1999-2002 over the study region, leaving 70.0 Tg C yr-1 and 7.9 Tg C yr-1 to accumulate as coarse woody debris and soil C, respectively. While avoided deforestation is central to crediting rainforest nations for reduced carbon emissions, the extent and intensity of selective logging are also critical to determining carbon emissions in the context of Reduced Emissions from Deforestation and Forest Degradation (REDD). We show that a combination of automated high-resolution satellite monitoring and detailed forest C modeling can yield spatially explicit estimates of harvest related C losses and subsequent recovery in support of REDD and other international carbon market mechanisms.

  7. A selective logging mechanism for hardware transactional memory systems

    OpenAIRE

    Lupon Navazo, Marc; Magklis, Grigorios; González Colás, Antonio María

    2011-01-01

    Log-based Hardware Transactional Memory (HTM) systems offer an elegant solution to handle speculative data that overflow transactional L1 caches. By keeping the pre-transactional values on a software-resident log, speculative values can be safely moved across the memory hierarchy, without requiring expensive searches on L1 misses or commits.

  8. Problems of calibrating measuring instruments for selective gamma-gamma logging

    International Nuclear Information System (INIS)

    Daniel, J.; Smolarova, H.

    1977-01-01

    Quantitative determination of copper content in the Novoveska Huta chalcopyrite deposit is described using selective gamma-gamma logging. Factors influencing the calibration quality are discussed. (author)

  9. Accreditation Council for Graduate Medical Education (ACGME) Surgery Resident Operative Logs: The Last Quarter Century.

    Science.gov (United States)

    Drake, Frederick Thurston; Aarabi, Shahram; Garland, Brandon T; Huntington, Ciara R; McAteer, Jarod P; Richards, Morgan K; Zern, Nicole Kansier; Gow, Kenneth W

    2017-05-01

    To describe secular trends in operative experience for surgical trainees across an extended period using the most comprehensive data available, the Accreditation Council for Graduate Medical Education (ACGME) case logs. Some experts have expressed concern that current trainees are inadequately prepared for independent practice. One frequently mentioned factor is whether duty hours' restrictions (DHR) implemented in 2003 and 2004 contributed by reducing time spent in the operating room. A dataset was generated from annual ACGME reports. Operative volume for total major cases (TMC), defined categories, and four index laparoscopic procedures was evaluated. TMC dropped after implementation of DHR but rebounded after a transition period (949 vs 946 cases, P = nonsignificance). Abdominal cases increased from 22% of overall cases to 31%. Alimentary cases increased from 21% to 26%. Trauma and vascular surgery substantially decreased. For trauma, this drop took place well before DHR. The decrease in vascular surgery also began before DHR but continued afterward as well: 148 cases/resident in the late 1990s to 107 currently. Although total operative volume rebounded after implementation of DHR, diversity of operative experienced narrowed. The combined increase in alimentary and abdominal cases is nearly 13%, over a half-year's worth of operating in 5-year training programs. Bedrock general surgery cases-trauma, vascular, pediatrics, and breast-decreased. Laparoscopic operations have steadily increased. If the competence of current graduates has, in fact, diminished. Our analysis suggests that operative volume is not the problem. Rather, changing disease processes, subspecialization, reductions in resident autonomy, and technical innovation challenge how today's general surgeons are trained.

  10. An ecosystem model for tropical forest disturbance and selective logging

    Science.gov (United States)

    Maoyi Huang; Gregory P. Asner; Michael Keller; Joseph A. Berry

    2008-01-01

    [1] A new three-dimensional version of the Carnegie-Ames-Stanford Approach (CASA) ecosystem model (CASA-3D) was developed to simulate regional carbon cycling in tropical forest ecosystems after disturbances such as logging. CASA-3D has the following new features: (1) an alternative approach for calculating absorbed photosynthetically active radiation (APAR) using new...

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

    Science.gov (United States)

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

    2013-04-01

    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

  12. Logging costs and production rates for the group selection cutting method

    Science.gov (United States)

    Philip M. McDonald

    1965-01-01

    Young-growth, mixed-conifer stands were logged by a group-selection method designed to create openings 30, 60, and 90 feet in diameter. Total costs for felling, limbing, bucking, and skidding on these openings ranged from $7.04 to $7.99 per thousand board feet. Cost differences between openings were not statistically significant. Logging costs for group selection...

  13. Selective logging: does the imprint remain on tree structure and composition after 45 years?

    Science.gov (United States)

    Osazuwa-Peters, Oyomoare L.; Chapman, Colin A.; Zanne, Amy E.

    2015-01-01

    Selective logging of tropical forests is increasing in extent and intensity. The duration over which impacts of selective logging persist, however, remains an unresolved question, particularly for African forests. Here, we investigate the extent to which a past selective logging event continues to leave its imprint on different components of an East African forest 45 years later. We inventoried 2358 stems ≥10 cm in diameter in 26 plots (200 m × 10 m) within a 5.2 ha area in Kibale National Park, Uganda, in logged and unlogged forest. In these surveys, we characterized the forest light environment, taxonomic composition, functional trait composition using three traits (wood density, maximum height and maximum diameter) and forest structure based on three measures (stem density, total basal area and total above-ground biomass). In comparison to unlogged forests, selectively logged forest plots in Kibale National Park on average had higher light levels, different structure characterized by lower stem density, lower total basal area and lower above-ground biomass, and a distinct taxonomic composition driven primarily by changes in the relative abundance of species. Conversely, selectively logged forest plots were like unlogged plots in functional composition, having similar community-weighted mean values for wood density, maximum height and maximum diameter. This similarity in functional composition irrespective of logging history may be due to functional recovery of logged forest or background changes in functional attributes of unlogged forest. Despite the passage of 45 years, the legacy of selective logging on the tree community in Kibale National Park is still evident, as indicated by distinct taxonomic and structural composition and reduced carbon storage in logged forest compared with unlogged forest. The effects of selective logging are exerted via influences on tree demography rather than functional trait composition. PMID:27293697

  14. Contrasting taxonomic and functional responses of a tropical tree community to selective logging

    OpenAIRE

    Baraloto, C.; Hérault, B.; Paine, C. E. T.; Massot, H.; Blanc, L.; Bonal, D.; Molino, Jean-François; Nicolini, E. A.; Sabatier, Daniel

    2012-01-01

    1. Considerable debate surrounds the extent to which tropical forests can be managed for resource extraction while conserving biodiversity and ecosystem properties, which depend on functional composition. Here we evaluate the compatibility of these aims by examining the effects of logging on taxonomic and functional diversity and composition in a tropical forest. 2. Twenty years after selective logging, we inventoried 4140 stems regenerating in logging gaps and adjacent undisturbed areas, and...

  15. Logging damage using an individual tree selection practice in Appalachian hardwood stands

    Science.gov (United States)

    Neil I. Lamson; H. Clay Smith; Gary W. Miller

    1985-01-01

    Four West Virginia hardwood stands, managed using individual-tree selection for the past 30 years, were examined after the third and, in one instance, the fourth periodic harvest to determine the severity of logging damage. On existing skid roads, trees were removed with a rubber-tired skidder or a crawler tractor with a rubber-tired arch. Logging damage reduced...

  16. Automated method for measuring the extent of selective logging damage with airborne LiDAR data

    Science.gov (United States)

    Melendy, L.; Hagen, S. C.; Sullivan, F. B.; Pearson, T. R. H.; Walker, S. M.; Ellis, P.; Kustiyo; Sambodo, Ari Katmoko; Roswintiarti, O.; Hanson, M. A.; Klassen, A. W.; Palace, M. W.; Braswell, B. H.; Delgado, G. M.

    2018-05-01

    Selective logging has an impact on the global carbon cycle, as well as on the forest micro-climate, and longer-term changes in erosion, soil and nutrient cycling, and fire susceptibility. Our ability to quantify these impacts is dependent on methods and tools that accurately identify the extent and features of logging activity. LiDAR-based measurements of these features offers significant promise. Here, we present a set of algorithms for automated detection and mapping of critical features associated with logging - roads/decks, skid trails, and gaps - using commercial airborne LiDAR data as input. The automated algorithm was applied to commercial LiDAR data collected over two logging concessions in Kalimantan, Indonesia in 2014. The algorithm results were compared to measurements of the logging features collected in the field soon after logging was complete. The automated algorithm-mapped road/deck and skid trail features match closely with features measured in the field, with agreement levels ranging from 69% to 99% when adjusting for GPS location error. The algorithm performed most poorly with gaps, which, by their nature, are variable due to the unpredictable impact of tree fall versus the linear and regular features directly created by mechanical means. Overall, the automated algorithm performs well and offers significant promise as a generalizable tool useful to efficiently and accurately capture the effects of selective logging, including the potential to distinguish reduced impact logging from conventional logging.

  17. Spatial and temporal dynamics of forest canopy gaps following selective logging in the eastern Amazon.

    Science.gov (United States)

    GREGORY P. ASNER; MICHAEL KELLER; JOSEN M. SILVA

    2004-01-01

    Selective logging is a dominant form of land use in the Amazon basin and throughout the humid tropics, yet little is known about the spatial variability of forest canopy gap formation and closure following timber harvests. We established chronosequences of large-area (14–158 ha) selective logging sites spanning a 3.5-year period of forest regeneration and two distinct...

  18. A risk index for multicriterial selection of a logging system with low environmental impact

    Energy Technology Data Exchange (ETDEWEB)

    Horodnic, Sergiu Andrei, E-mail: horodnic@usv.ro

    2015-02-15

    Setting up the working stages in forest operations is conditioned by environmental protection and forest health requirements. This paper exposes a method for improving the decision-making process by choosing the most environmentally effective logging systems according to terrain configuration and stand characteristics. Such a methodology for selecting machines or logging systems accounting for environment, safety as well as economics, becomes mandatory in the context of sustainable management of forest with multiple functions. Based on analytic hierarchy process analysis the following classification of the environmental performance for four considered alternatives was obtained: skyline system (42.43%), forwarder system (20.22%), skidder system (19.92%) and horse logging system (17.43%). Further, an environmental risk matrix for the most important 28 risk factors specific to any work equipment used in forest operations was produced. In the end, a multicriterial analysis generated a risk index RI ranging between 1.0 and 3.5, which could help choosing the optimal combination of logging system and logging equipment with low environmental impact. In order to demonstrate the usefulness of the proposed approach, a simple application in specific conditions of a harvesting site is presented. - Highlights: • We propose a decision-making algorithm to select eco-friendly logging systems. • Analytic hierarchy process was applied for ranking 4 types of logging systems. • An environmental risk matrix with 28 risk factors in forest operations was made up.

  19. A risk index for multicriterial selection of a logging system with low environmental impact

    International Nuclear Information System (INIS)

    Horodnic, Sergiu Andrei

    2015-01-01

    Setting up the working stages in forest operations is conditioned by environmental protection and forest health requirements. This paper exposes a method for improving the decision-making process by choosing the most environmentally effective logging systems according to terrain configuration and stand characteristics. Such a methodology for selecting machines or logging systems accounting for environment, safety as well as economics, becomes mandatory in the context of sustainable management of forest with multiple functions. Based on analytic hierarchy process analysis the following classification of the environmental performance for four considered alternatives was obtained: skyline system (42.43%), forwarder system (20.22%), skidder system (19.92%) and horse logging system (17.43%). Further, an environmental risk matrix for the most important 28 risk factors specific to any work equipment used in forest operations was produced. In the end, a multicriterial analysis generated a risk index RI ranging between 1.0 and 3.5, which could help choosing the optimal combination of logging system and logging equipment with low environmental impact. In order to demonstrate the usefulness of the proposed approach, a simple application in specific conditions of a harvesting site is presented. - Highlights: • We propose a decision-making algorithm to select eco-friendly logging systems. • Analytic hierarchy process was applied for ranking 4 types of logging systems. • An environmental risk matrix with 28 risk factors in forest operations was made up

  20. Selective logging and damage to unharvested trees in a hyrcanian forest of Iran

    OpenAIRE

    Farshad Keivan Behjou; Omid Ghafarzade Mollabashi

    2012-01-01

    Selective logging in mature hardwood stands of Caspian forests often causes physical damage to residual trees through felling and skidding operations, resulting in a decline in bole quality and subsequent loss of tree value. This study evaluated the logging damage to residual trees following logging operations. A total density of 5.1 trees/ha and 17.3 m3/ha of wood were harvested. On average, 9.8 trees were damaged for every tree extracted, including 8 trees destroyed or severely damaged. The...

  1. F...ffccts of selective logging and exploitation of non-timber forest ...

    African Journals Online (AJOL)

    medicines, craft materials and rood, whose value is significant to the communities neighbouring the forest. This study examined the effects of selective logging on the Budongo torcst reserve. Answers were sought to the following questions: what were the effects ofselcctivc Jogging on species abundance, wood volume.

  2. Forest canopy damage and recovery in reduced-impact and conventional selective logging in eastern Para, Brazil.

    Science.gov (United States)

    Rodrigo Pereira Jr.; Johan Zweedea; Gregory P. Asnerb; Keller; Michael

    2002-01-01

    We investigated ground and canopy damage and recovery following conventional logging and reduced-impact logging (RIL) of moist tropical forest in the eastern Amazon of Brazil. Paired conventional and RIL blocks were selectively logged with a harvest intensity of approximately 23 m3 ha

  3. Stand structure, composition and illegal logging in selectively logged production forests of Myanmar: Comparison of two compartments subject to different cutting frequency

    Directory of Open Access Journals (Sweden)

    Tual Cin Khai

    2016-07-01

    Full Text Available Appropriate cutting cycles and annual allowable cuts are crucial to ensure sustainability of tropical selective logging, but there have been limited field data to verify long-term effects of different cutting cycles. This study reveals some evidence of forest degradation in selectively logged production forests of Myanmar, which are subject to inappropriate cutting frequency. We compared stand structure, commercial species composition, and incidence of illegal logging between two compartments with low (LCF; 1 time and high (HCF; 5 times cutting frequency over a recent 18 years. Prior to the latest cutting, LCF had 176 trees ha−1 with an inverted-J shape distribution of diameter at breast height (DBH, including a substantial amount of teak (Tectona grandis and other commercially important species in each DBH class. HCF prior to the latest cut had only 41 trees ha−1 without many commercially important species. At HCF, nearly half the standing trees of various species and size were illegally cut following legal operations; this was for charcoal making in nearby kilns. At LCF, two species, teak and Xylia xylocarpa, were cut illegally and sawn for timber on the spot. More extensive and systematic surveys are needed to generalize the findings of forest degradation and illegal logging. However, our study calls for urgent reconsideration of logging practices with high cutting frequency, which can greatly degrade forests with accompanying illegal logging, and for rehabilitating strongly degraded, bamboo-dominated forests. To reduce illegal logging, it would be important to pay more attention on a MSS regulation stating that logging roads should be destroyed after logging operations.

  4. Automated Detection of Selective Logging in Amazon Forests Using Airborne Lidar Data and Pattern Recognition Algorithms

    Science.gov (United States)

    Keller, M. M.; d'Oliveira, M. N.; Takemura, C. M.; Vitoria, D.; Araujo, L. S.; Morton, D. C.

    2012-12-01

    Selective logging, the removal of several valuable timber trees per hectare, is an important land use in the Brazilian Amazon and may degrade forests through long term changes in structure, loss of forest carbon and species diversity. Similar to deforestation, the annual area affected by selected logging has declined significantly in the past decade. Nonetheless, this land use affects several thousand km2 per year in Brazil. We studied a 1000 ha area of the Antimary State Forest (FEA) in the State of Acre, Brazil (9.304 ○S, 68.281 ○W) that has a basal area of 22.5 m2 ha-1 and an above-ground biomass of 231 Mg ha-1. Logging intensity was low, approximately 10 to 15 m3 ha-1. We collected small-footprint airborne lidar data using an Optech ALTM 3100EA over the study area once each in 2010 and 2011. The study area contained both recent and older logging that used both conventional and technologically advanced logging techniques. Lidar return density averaged over 20 m-2 for both collection periods with estimated horizontal and vertical precision of 0.30 and 0.15 m. A relative density model comparing returns from 0 to 1 m elevation to returns in 1-5 m elevation range revealed the pattern of roads and skid trails. These patterns were confirmed by ground-based GPS survey. A GIS model of the road and skid network was built using lidar and ground data. We tested and compared two pattern recognition approaches used to automate logging detection. Both segmentation using commercial eCognition segmentation and a Frangi filter algorithm identified the road and skid trail network compared to the GIS model. We report on the effectiveness of these two techniques.

  5. Evaluating the sustainable mining contractor selection problems: An imprecise last aggregation preference selection index method

    Directory of Open Access Journals (Sweden)

    Mohammad Panahi Borujeni

    2017-01-01

    Full Text Available The increasing complexity surrounding decision-making situations has made it inevitable for practitioners to apply ideas from a group of experts or decision makers (DMs instead of individuals. In a large proportion of recent studies, not enough attention has been paid to considering uncertainty in practical ways. In this paper, a hesitant fuzzy preference selection index (HFPSI method is proposed based on a new soft computing approach with risk preferences of DMs to deal with imprecise multi-criteria decision-making problems. Meanwhile, qualitative assessing criteria are considered in the process of the proposed method to help the DMs by providing suitable expressions of membership degrees for an element under a set. Moreover, the best alternative is selected based on considering the concepts of preference relation and hesitant fuzzy sets, simultaneously. Therefore, DMs' weights are determined according to the proposed hesitant fuzzy compromise solution technique to prevent judgment errors. Moreover, the proposed method has been extended based on the last aggregation method by aggregating the DMs' opinions during the last stage to avoid data loss. In this respect, a real case study about the mining contractor selection problem is provided to represent the effectiveness and efficiency of the proposed HFPSI method in practice. Then, a comparative analysis is performed to show the feasibility of the presented approach. Finally, sensitivity analysis is carried out to show the effect of considering the DMs' weights and last aggregation approach in a dispersion of the alternatives’ ranking values.

  6. Sleep Promotes Lasting Changes in Selective Memory for Emotional Scenes

    Directory of Open Access Journals (Sweden)

    Jessica ePayne

    2012-11-01

    Full Text Available Although we know that emotional events enjoy a privileged status in our memories, we still have much to learn about how emotional memories are processed, stored, and how they change over time. Here we show a positive association between REM sleep and the selective consolidation of central, negative aspects of complex scenes. Moreover, we show that the placement of sleep is critical for this selective emotional memory benefit. When testing occurred 24hr post-encoding, subjects who slept soon after learning (24hr Sleep First group had superior memory for emotional objects compared to subjects whose sleep was delayed for 16hr post-encoding following a full day of wakefulness (24hr Wake First group. However, this increase in memory for emotional objects corresponded with a decrease in memory for the neutral backgrounds on which these objects were placed. Furthermore, memory for emotional objects in the 24hr Sleep First group was comparable to performance after just a 12hr delay containing a night of sleep, suggesting that sleep soon after learning selectively stabilizes emotional memory. These results suggest that the sleeping brain preserves in long-term memory only what is emotionally salient and perhaps most adaptive to remember.

  7. Sleep promotes lasting changes in selective memory for emotional scenes.

    Science.gov (United States)

    Payne, Jessica D; Chambers, Alexis M; Kensinger, Elizabeth A

    2012-01-01

    Although we know that emotional events enjoy a privileged status in our memories, we still have much to learn about how emotional memories are processed, stored, and how they change over time. Here we show a positive association between REM sleep and the selective consolidation of central, negative aspects of complex scenes. Moreover, we show that the placement of sleep is critical for this selective emotional memory benefit. When testing occurred 24 h post-encoding, subjects who slept soon after learning (24 h Sleep First group) had superior memory for emotional objects compared to subjects whose sleep was delayed for 16 h post-encoding following a full day of wakefulness (24 h Wake First group). However, this increase in memory for emotional objects corresponded with a decrease in memory for the neutral backgrounds on which these objects were placed. Furthermore, memory for emotional objects in the 24 h Sleep First group was comparable to performance after just a 12 h delay containing a night of sleep, suggesting that sleep soon after learning selectively stabilizes emotional memory. These results suggest that the sleeping brain preserves in long-term memory only what is emotionally salient and perhaps most adaptive to remember.

  8. Effects of Selective Logging on Birds in the Sierra de Coalcoman, Sierra Madre del Sur, Michoacan, Western Mexico

    Science.gov (United States)

    Jose Fernando Villaseñor; Neyra Sosa; Laura Villaseñor

    2005-01-01

    In order to determine the effects of selective logging on pine-oak forest?s bird communities in central-western Mexico, we gathered information through 10-min point counts in plots without wood extraction and sites logged at different times in the past (1, 4, and 8 years). We did not find evidences to argue for effects of logging on bird communities; the study plots...

  9. Effects of selective logging on large mammal populations in a remote indigenous territory in the northern Peruvian Amazon

    OpenAIRE

    Pedro Mayor; Pedro Pérez-Peña; Mark Bowler; Pablo E. Puertas; Maire Kirkland; Richard Bodmer

    2015-01-01

    We examined the effects of selective timber logging carried out by local indigenous people in remote areas within indigenous territories on the mammal populations of the Yavari-Mirin River basin on the Peru-Brazil border. Recent findings show that habitat change in the study area is minimal, and any effect of logging activities on large mammal populations is highly likely to be the result of hunting associated with logging operations. We used hunting registers to estimate the monthly and year...

  10. Long-term responses of populations and communities of trees to selective logging in tropical rain forests in Guyana

    NARCIS (Netherlands)

    Arets, E.J.M.M. (Eric Jacobus Monica Maria)

    2005-01-01

    Since only a small area of Guyana's forest can be effectively protected and because timber harvesting is an important source of income, logged forests will play an important role in the conservation of biodiversity in Guyana. Selective logging, in which only a few trees per hectare are harvested and

  11. Log-linear model based behavior selection method for artificial fish swarm algorithm.

    Science.gov (United States)

    Huang, Zhehuang; Chen, Yidong

    2015-01-01

    Artificial fish swarm algorithm (AFSA) is a population based optimization technique inspired by social behavior of fishes. In past several years, AFSA has been successfully applied in many research and application areas. The behavior of fishes has a crucial impact on the performance of AFSA, such as global exploration ability and convergence speed. How to construct and select behaviors of fishes are an important task. To solve these problems, an improved artificial fish swarm algorithm based on log-linear model is proposed and implemented in this paper. There are three main works. Firstly, we proposed a new behavior selection algorithm based on log-linear model which can enhance decision making ability of behavior selection. Secondly, adaptive movement behavior based on adaptive weight is presented, which can dynamically adjust according to the diversity of fishes. Finally, some new behaviors are defined and introduced into artificial fish swarm algorithm at the first time to improve global optimization capability. The experiments on high dimensional function optimization showed that the improved algorithm has more powerful global exploration ability and reasonable convergence speed compared with the standard artificial fish swarm algorithm.

  12. Log-Linear Model Based Behavior Selection Method for Artificial Fish Swarm Algorithm

    Directory of Open Access Journals (Sweden)

    Zhehuang Huang

    2015-01-01

    Full Text Available Artificial fish swarm algorithm (AFSA is a population based optimization technique inspired by social behavior of fishes. In past several years, AFSA has been successfully applied in many research and application areas. The behavior of fishes has a crucial impact on the performance of AFSA, such as global exploration ability and convergence speed. How to construct and select behaviors of fishes are an important task. To solve these problems, an improved artificial fish swarm algorithm based on log-linear model is proposed and implemented in this paper. There are three main works. Firstly, we proposed a new behavior selection algorithm based on log-linear model which can enhance decision making ability of behavior selection. Secondly, adaptive movement behavior based on adaptive weight is presented, which can dynamically adjust according to the diversity of fishes. Finally, some new behaviors are defined and introduced into artificial fish swarm algorithm at the first time to improve global optimization capability. The experiments on high dimensional function optimization showed that the improved algorithm has more powerful global exploration ability and reasonable convergence speed compared with the standard artificial fish swarm algorithm.

  13. Impact of selective logging on inbreeding and gene dispersal in an Amazonian tree population of Carapa guianensis Aubl.

    Science.gov (United States)

    Cloutier, D; Kanashiro, M; Ciampi, A Y; Schoen, D J

    2007-02-01

    Selective logging may impact patterns of genetic diversity within populations of harvested forest tree species by increasing distances separating conspecific trees, and modifying physical and biotic features of the forest habitat. We measured levels of gene diversity, inbreeding, pollen dispersal and spatial genetic structure (SGS) of an Amazonian insect-pollinated Carapa guianensis population before and after commercial selective logging. Similar levels of gene diversity and allelic richness were found before and after logging in both the adult and the seed generations. Pre- and post-harvest outcrossing rates were high, and not significantly different from one another. We found no significant levels of biparental inbreeding either before or after logging. Low levels of pollen pool differentiation were found, and the pre- vs. post-harvest difference was not significant. Pollen dispersal distance estimates averaged between 75 m and 265 m before logging, and between 76 m and 268 m after logging, depending on the value of tree density and the dispersal model used. There were weak and similar levels of differentiation of allele frequencies in the adults and in the pollen pool, before and after logging occurred, as well as weak and similar pre- and post-harvest levels of SGS among adult trees. The large neighbourhood sizes estimated suggest high historical levels of gene flow. Overall our results indicate that there is no clear short-term genetic impact of selective logging on this population of C. guianensis.

  14. Genetic structure and genetic diversity of Swietenia macrophylla in areas subjected to selective logging in Quintana Roo, Mexico

    OpenAIRE

    Alcalá, Raúl Ernesto; Cruz, Silvia De la; Gutiérrez-Granados, Gabriel

    2015-01-01

    The hypothesis that selective logging has a negative effect by altering the genetic parameters of tropical tree species was evaluated. The genetic diversity and genetic structure between adult trees (N = 47) and saplings (N = 50) of Swietenia macrophylla were contrasted within an area subjected to selective logging in the Mayan zone. Although differences in the number of alleles and in their frequencies were detected between both groups, the observed and expected heterozygosity and the coeffi...

  15. Carbon recovery dynamics following disturbance by selective logging in Amazonian forests

    Science.gov (United States)

    Piponiot, Camille; Sist, Plinio; Mazzei, Lucas; Peña-Claros, Marielos; Putz, Francis E; Rutishauser, Ervan; Shenkin, Alexander; Ascarrunz, Nataly; de Azevedo, Celso P; Baraloto, Christopher; França, Mabiane; Guedes, Marcelino; Honorio Coronado, Eurídice N; d'Oliveira, Marcus VN; Ruschel, Ademir R; da Silva, Kátia E; Doff Sotta, Eleneide; de Souza, Cintia R; Vidal, Edson; West, Thales AP; Hérault, Bruno

    2016-01-01

    When 2 Mha of Amazonian forests are disturbed by selective logging each year, more than 90 Tg of carbon (C) is emitted to the atmosphere. Emissions are then counterbalanced by forest regrowth. With an original modelling approach, calibrated on a network of 133 permanent forest plots (175 ha total) across Amazonia, we link regional differences in climate, soil and initial biomass with survivors’ and recruits’ C fluxes to provide Amazon-wide predictions of post-logging C recovery. We show that net aboveground C recovery over 10 years is higher in the Guiana Shield and in the west (21 ±3 Mg C ha-1) than in the south (12 ±3 Mg C ha-1) where environmental stress is high (low rainfall, high seasonality). We highlight the key role of survivors in the forest regrowth and elaborate a comprehensive map of post-disturbance C recovery potential in Amazonia. DOI: http://dx.doi.org/10.7554/eLife.21394.001 PMID:27993185

  16. The paleo-climate change of Chaidam Basin during the last 2.85 Ma recorded by gamma-ray logging

    International Nuclear Information System (INIS)

    Chen Ye; Yuan Linwang; Liu Zechun

    2000-01-01

    The author deals with mainly the aspect of paleo-climate change of the basin. The approach used for the study consisted of (1) establishing the paleo-climate curve of the basin according to the climate indices, including the spore-pollen statistics, carbonate content and δ 18 O, obtained from the samples of the 760 m continuously-cored exploration holes sited in the basin, (2) comparing the paleo-climate curve with the natural gamma-logs of the same exploration holes, and (3) determining the paleo-climatic changes in the last 2.85 Ma on the basis of detailed geochronological calculations. These results are extremely important for comparison with the δ 18 O-based climate curve derived from the ODP659 in the Atlantic Ocean and with the cycles of paleosol in the Chinese loess

  17. Forest Fragmentation and Selective Logging Have Inconsistent Effects on Multiple Animal-Mediated Ecosystem Processes in a Tropical Forest

    Science.gov (United States)

    Schleuning, Matthias; Farwig, Nina; Peters, Marcell K.; Bergsdorf, Thomas; Bleher, Bärbel; Brandl, Roland; Dalitz, Helmut; Fischer, Georg; Freund, Wolfram; Gikungu, Mary W.; Hagen, Melanie; Garcia, Francisco Hita; Kagezi, Godfrey H.; Kaib, Manfred; Kraemer, Manfred; Lung, Tobias; Schaab, Gertrud; Templin, Mathias; Uster, Dana; Wägele, J. Wolfgang; Böhning-Gaese, Katrin

    2011-01-01

    Forest fragmentation and selective logging are two main drivers of global environmental change and modify biodiversity and environmental conditions in many tropical forests. The consequences of these changes for the functioning of tropical forest ecosystems have rarely been explored in a comprehensive approach. In a Kenyan rainforest, we studied six animal-mediated ecosystem processes and recorded species richness and community composition of all animal taxa involved in these processes. We used linear models and a formal meta-analysis to test whether forest fragmentation and selective logging affected ecosystem processes and biodiversity and used structural equation models to disentangle direct from biodiversity-related indirect effects of human disturbance on multiple ecosystem processes. Fragmentation increased decomposition and reduced antbird predation, while selective logging consistently increased pollination, seed dispersal and army-ant raiding. Fragmentation modified species richness or community composition of five taxa, whereas selective logging did not affect any component of biodiversity. Changes in the abundance of functionally important species were related to lower predation by antbirds and higher decomposition rates in small forest fragments. The positive effects of selective logging on bee pollination, bird seed dispersal and army-ant raiding were direct, i.e. not related to changes in biodiversity, and were probably due to behavioural changes of these highly mobile animal taxa. We conclude that animal-mediated ecosystem processes respond in distinct ways to different types of human disturbance in Kakamega Forest. Our findings suggest that forest fragmentation affects ecosystem processes indirectly by changes in biodiversity, whereas selective logging influences processes directly by modifying local environmental conditions and resource distributions. The positive to neutral effects of selective logging on ecosystem processes show that the

  18. Effects of selective logging on large mammal populations in a remote indigenous territory in the northern Peruvian Amazon

    Directory of Open Access Journals (Sweden)

    Pedro Mayor

    2015-12-01

    Full Text Available We examined the effects of selective timber logging carried out by local indigenous people in remote areas within indigenous territories on the mammal populations of the Yavari-Mirin River basin on the Peru-Brazil border. Recent findings show that habitat change in the study area is minimal, and any effect of logging activities on large mammal populations is highly likely to be the result of hunting associated with logging operations. We used hunting registers to estimate the monthly and yearly biomass extracted during timber operations and to calculate the catch per unit effort (CPUE in subsistence hunting in the community of Esperanza 2 to 5 years before logging activities started and 4 to 7 years after logging began. We also used line transects and the distance method to estimate animal densities before and after logging. We found that 1389 hunted animals and 27,459 kg of mammal biomass were extracted per year from logging concessions. CPUE for ungulates declined; however, it increased for other mammal orders, such as rodents and primates, indicating a shift to alternative prey items. Although collared peccaries (Pecari tajacu and tapirs (Tapirus terrestris may also have declined in numbers, this shift may have been caused by a possibly natural population crash in white-lipped peccaries (Tayassu pecari that coincided with the logging periods. We found no evidence that populations of primates were reduced by the logging activities. Because primates are sensitive to hunting, and their populations were of principal concern as logging commenced, this indicates that these forests remain of high conservation value. The unusual socioeconomic situation of these remote territories may mean that they are compatible with wildlife conservation in the Yavari-Mirin basin.

  19. Does selective logging stress tropical forest invertebrates? Using fat stores to examine sublethal responses in dung beetles.

    Science.gov (United States)

    França, Filipe; Barlow, Jos; Araújo, Bárbara; Louzada, Julio

    2016-12-01

    The increased global demand for tropical timber has driven vast expanses of tropical forests to be selectively logged worldwide. While logging impacts on wildlife are predicted to change species distribution and abundance, the underlying physiological responses are poorly understood. Although there is a growing consensus that selective logging impacts on natural populations start with individual stress-induced sublethal responses, this literature is dominated by investigations conducted with vertebrates from temperate zones. Moreover, the sublethal effects of human-induced forest disturbance on tropical invertebrates have never been examined. To help address this knowledge gap, we examined the body fat content and relative abundance of three dung beetle species (Coleoptera: Scarabaeinae) with minimum abundance of 40 individuals within each examined treatment level. These were sampled across 34 plots in a before-after control-impact design (BACI) in a timber concession area of the Brazilian Amazon. For the first time, we present evidence of logging-induced physiological stress responses in tropical invertebrates. Selective logging increased the individual levels of fat storage and reduced the relative abundance of two dung beetle species. Given this qualitative similarity, we support the measurement of body fat content as reliable biomarker to assess stress-induced sublethal effects on dung beetles. Understanding how environmental modification impacts the wildlife has never been more important. Our novel approach provides new insights into the mechanisms through which forest disturbances impose population-level impacts on tropical invertebrates.

  20. Effect of selective logging on floristic and structural composition in a forest fragment from Amazon Biome

    Directory of Open Access Journals (Sweden)

    Karen Janones da Rocha

    2017-04-01

    Full Text Available This study was conducted in one region of a Seasonal Semideciduous Forest located in Tapurah (Mato Grosso State, Brazil with the aim of studying its floristic and structural composition. The fixed area method was applied to 10 × 250 m clusters, allocating and measuring five clusters with five subunits of 500 m² each. Species with a diameter at breast height greater than or equal to 10 cm were considered, and the sample sufficiency of the floristic survey was verified by a species accumulation curve. The similarities between the sample subunits were calculated by the Jaccard Similarity Index, and the species diversity with the Shannon Diversity Index and Pielou Evenness Index. The horizontal vegetation structure was characterized by density, frequency, dominance and the values of ecological importance, and diametric distribution were assessed by the Spiegel procedure. The families Vochysiaceae, Fabaceae and Sapindaceae were highly represented, and Qualea paraensis, Aspidosperma discolor and Matayba arborescens were the most important species. A high diversity and low ecological dominance were found, and the diametric structure of the trees presented a negative exponential distribution. In general, the structure, floristic composition and richness of vegetation correspond to a forest with stable and autoregenerative community after selective logging.

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

    Science.gov (United States)

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

    2011-01-01

    Long-term (21–30 years) erosional responses of rainforest terrain in the Upper Segama catchment, Sabah, to selective logging are assessed at slope, small and large catchment scales. In the 0.44 km2 Baru catchment, slope erosion measurements over 1990–2010 and sediment fingerprinting indicate that sediment sources 21 years after logging in 1989 are mainly road-linked, including fresh landslips and gullying of scars and toe deposits of 1994–1996 landslides. Analysis and modelling of 5–15 min stream-suspended sediment and discharge data demonstrate a reduction in storm-sediment response between 1996 and 2009, but not yet to pre-logging levels. An unmixing model using bed-sediment geochemical data indicates that 49 per cent of the 216 t km−2 a−1 2009 sediment yield comes from 10 per cent of its area affected by road-linked landslides. Fallout 210Pb and 137Cs values from a lateral bench core indicate that sedimentation rates in the 721 km2 Upper Segama catchment less than doubled with initially highly selective, low-slope logging in the 1980s, but rose 7–13 times when steep terrain was logged in 1992–1993 and 1999–2000. The need to keep steeplands under forest is emphasized if landsliding associated with current and predicted rises in extreme rainstorm magnitude-frequency is to be reduced in scale. PMID:22006973

  2. Remote sensing of selective logging in Amazonia Assessing limitations based on detailed field observations, Landsat ETM+, and textural analysis.

    Science.gov (United States)

    Gregory P. Asner; Michael Keller; Rodrigo Pereira; Johan C. Zweede

    2002-01-01

    We combined a detailed field study of forest canopy damage with calibrated Landsat 7 Enhanced Thematic Mapper Plus (ETM+) reflectance data and texture analysis to assess the sensitivity of basic broadband optical remote sensing to selective logging in Amazonia. Our field study encompassed measurements of ground damage and canopy gap fractions along a chronosequence of...

  3. Well Inventory and Geophysical Logging of Selected Wells in Troup County, Georgia, 2007-2008

    Science.gov (United States)

    Peck, Michael F.; Leeth, David C.; Hamrick, Michael D.

    2008-01-01

    The U.S. Geological Survey (USGS) - in cooperation with the Troup County Board of Commissioners - conducted a well inventory to provide information to help evaluate ground-water resources for Troup County, Georgia. In addition, borehole geophysical logs were collected in selected wells to provide a better understanding of the subsurface geologic and water-bearing characteristics in specific areas of interest. This investigation provides information to help guide future ground-water development and water-management decisions for Troup County while enhancing understanding of the hydrogeology of fractured rocks in the Piedmont physiographic province. This report presents well data compiled from USGS files and from site visits to wells during November and December 2007. Data were entered into the USGS National Water Information System (NWIS) and made available on the Web at http://waterdata.usgs.gov/ga/nwis/inventory. Previous studies of ground-water resources have been conducted in the vicinity, but did not include Troup County. The ground-water resources of Heard and Coweta Counties, located north and northeast, respectively, of Troup County were part of a larger study by Cressler and others (1983) that encompassed the Greater Atlanta Region. That study evaluated the quantity and quality of ground water in the Atlanta region and described the methods that could be used for locating high-yielding wells in the Piedmont Province. The geology underlying the Atlanta area is similar to that underlying Troup County. Clarke and Peck (1990) conducted a similar investigation that included Meriwether and Coweta Counties, located to the east and northeast of Troup County.

  4. Geophysical borehole logging in selected areas in the Greater Accra plains and the Densu river basin

    International Nuclear Information System (INIS)

    Amartey, E. A.

    2009-06-01

    Geophysical borehole logging was complemented by Vertical Electrical Sounding (VES) method to study fractured bedrock aquifer systems on the compounds of Ghana Atomic Energy Commission (GAEC), Water Research Institute (WRI) in the Accra Plains and the Hydrometric Station of the Department of Geology, University of Ghana at Buokrom in the Densu River Basin. Single-point resistance, resistivity and natural gamma logging in a total of nine boreholes were conducted to identify and characterize the various aquifers in the study areas. Results obtained from the single-point resistance and resistivity logs showed clearly the characteristics of water-bearing fracture zones in the various rock formations. The gamma logs obtained for each area were correlated to form hydrostratigraphic units to establish potential zones of high water-bearing fractures. VES modeled curves shows hydrogeological units of the geological formation which compares well with features obtained on the logs. The investigation identified fractured zone thicknesses of <1 m to 2 m at GAEC area, <1 m to 9 m at WRI area and <1 m to 10 m thicknesses at the Buokrom area. The fractured bedrock aquifers identified have been characterized based on their thicknesses as follows. Five minor (thickness < 5 m), two medium (thickness 5 m to 14 m) and three major (thickness ⩾15 m) fractures were identified at the GAEC area. At the WRI area three minor and five medium fractures were identified. Also four minor and five medium fractures were identified for the Buokrom area boreholes. (au)

  5. Impacts of selective logging on inbreeding and gene flow in two Amazonian timber species with contrasting ecological and reproductive characteristics.

    Science.gov (United States)

    Vinson, C C; Kanashiro, M; Harris, S A; Boshier, D H

    2015-01-01

    Selective logging in Brazil allows for the removal of up to 90% of trees above 50 cm diameter of a given timber species, independent of a species' life history characteristics or how quickly it will recover. The genetic and demographic effects of selective logging on two Amazonian timber species (Dipteryx odorata Leguminosae, Jacaranda copaia Bignoniaceae) with contrasting ecological and reproductive characteristics were assessed in the same forest. Genetic diversity and gene flow were characterized by genotyping adults and seed sampled before and after logging, using hypervariable microsatellite markers. Overall, there were no short-term genetic impacts on the J. copaia population, with commercial application of current Brazilian forest management regulations. In contrast, for D. Odorata, selective logging showed a range of genetic impacts, with a 10% loss of alleles, and reductions in siring by pollen from trees within the 546-ha study area (23-11%) and in the number of pollen donors per progeny array (2.8-1.6), illustrating the importance of the surrounding landscape. Asynchrony in flowering between D. odorata trees led to trees with no breeding partners, which could limit the species reproduction and regeneration under current regulations. The results are summarized with other published studies from the same site and the implications for forest management discussed. The different types and levels of impacts associated with each species support the idea that ecological and genetic information by species, ecological guild or reproductive group is essential in helping to derive sustainable logging guidelines for tropical forests. © 2014 John Wiley & Sons Ltd.

  6. Selective logging and fire as drivers of alien grass invasion in a Bolivian tropical dry forest

    NARCIS (Netherlands)

    Veldman, J.W.; Mostacedo, B.; Peña-Claros, M.; Putz, F.E.

    2009-01-01

    Logging is an integral component of most conceptual models that relate human land-use and climate change to tropical deforestation via positive-feedbacks involving fire. Given that grass invasions can substantially alter fire regimes, we studied grass distributions in a tropical dry forest 1-5 yr

  7. Minimizing bias in biomass allometry: Model selection and log transformation of data

    Science.gov (United States)

    Joseph Mascaro; undefined undefined; Flint Hughes; Amanda Uowolo; Stefan A. Schnitzer

    2011-01-01

    Nonlinear regression is increasingly used to develop allometric equations for forest biomass estimation (i.e., as opposed to the raditional approach of log-transformation followed by linear regression). Most statistical software packages, however, assume additive errors by default, violating a key assumption of allometric theory and possibly producing spurious models....

  8. Relative importance of various regeneration mechanisms in different restoration stages of Quercus variabilis forest after selective logging

    Directory of Open Access Journals (Sweden)

    Yaoqin Xue

    2014-08-01

    Full Text Available Aim of study: Quercus variabilis (Chinese cork oak reproduces asexually and sexually. This study aimed to determine the status and growth of asexual and sexual recruits of Q. variabilis in different forest recovery stages.Area of study: Three selective logged stands and one unlogged stand in Q. variabilis forest, Shaanxi Province, China.Material and Methods: Origin, number, basal diameter, height and size structure of Q. variabilis shoots (height ≤200 cm were investigated in the plots of 5, 10, and 20-years post-logging stands and unlogged stand. Effects of recovery stage on the density and growth of the three original recruits (stump sprouts, stem base sprouts and true seedlings were analysis by One-way ANOVA.Main results: Sprouts dominated logged stands, whereas true seedlings dominated unlogged stand, stem base sprouts only existed in 20-years post-logging and unlogged stands. Stump sprout density and sprout number per stump both declined with extended post-logging time. True seedlings density increased from 7 to 20 shoots/100 m2 as the postlogging time extended, and peaked in unlogged stand (94 shoots/100 m2. An ongoing size structure was observed in true seedlings in all stands. Stump sprouts were taller and greater than true seedlings.Research highlights: Stump sprouts contributed more to Q. variabilis forest recovery in the early stage after disturbance. The contribution of true seedlings was limited in the same stage, but they were beneficial for population long-term development. Stem base sprouts were most likely to be a survival strategy rather than a reproductive strategy.Key words: asexual reproduction; true seedling; post-logging time; Chinese cork oak.

  9. Contribution to the theory of interpretation of gamma natural selective logging and global

    International Nuclear Information System (INIS)

    Alpha, Aboubacrine.

    1982-10-01

    The gamma natural selective method allows the ''in situ'' measurement of the uranium content of ores independently of the value of the U/Ra equilibrium. The use of this methode meets two sorts of difficulties: - first, the gamma spectrum is distorted by some factors connected with the conditions of measurement: drilling mud, tubing, position of the probe in the borehole; - secondy, the interpretation of the anomaly I1 (low energy) requires the knowledge of μ1 (absorption coefficient for gamma ray) which is a function of the uranium content which is to be determined. The present work develops two original calculation methods which allow to overcome these difficulties. The principles used are mentionned hereafter. 1) It is shown that it is possible to calculate the numerical values of coefficients μ1 et μ2, without previous determination of the uranium grade, which eventually allows their calculation afterwards. 2) From the general formula of J.A. CZUBEK applying to infinite medium, a new formula applying to finite medium has been established. The formula thus obtained takes into account the measurement conditions. The last part contains an estimation of the errors allowing to specify the limits of validity of the method [fr

  10. Effect of selective logging on genetic diversity and gene flow in Cariniana legalis sampled from a cacao agroforestry system.

    Science.gov (United States)

    Leal, J B; Santos, R P; Gaiotto, F A

    2014-01-28

    The fragments of the Atlantic Forest of southern Bahia have a long history of intense logging and selective cutting. Some tree species, such as jequitibá rosa (Cariniana legalis), have experienced a reduction in their populations with respect to both area and density. To evaluate the possible effects of selective logging on genetic diversity, gene flow, and spatial genetic structure, 51 C. legalis individuals were sampled, representing the total remaining population from the cacao agroforestry system. A total of 120 alleles were observed from the 11 microsatellite loci analyzed. The average observed heterozygosity (0.486) was less than the expected heterozygosity (0.721), indicating a loss of genetic diversity in this population. A high fixation index (FIS = 0.325) was found, which is possibly due to a reduction in population size, resulting in increased mating among relatives. The maximum (1055 m) and minimum (0.095 m) distances traveled by pollen or seeds were inferred based on paternity tests. We found 36.84% of unique parents among all sampled seedlings. The progenitors of the remaining seedlings (63.16%) were most likely out of the sampled area. Positive and significant spatial genetic structure was identified in this population among classes 10 to 30 m away with an average coancestry coefficient between pairs of individuals of 0.12. These results suggest that the agroforestry system of cacao cultivation is contributing to maintaining levels of diversity and gene flow in the studied population, thus minimizing the effects of selective logging.

  11. Selected emissions and efficiencies of energy systems based on logging and sawmill residues

    International Nuclear Information System (INIS)

    Maelkki, Helena; Virtanen, Yrjoe

    2003-01-01

    Bioenergy has an important role in the implementation of the Kyoto agreement in Finland. The main sources of wood residues for energy production are logging areas and sawmills. The use of forest chips can be of great significance in reducing carbon dioxide emissions by replacing fossil fuels. Increasing the use of forest chips has environmental benefits, but it also includes possible environmental disadvantages. Therefore, system research is needed to assess the forest chip utilisation prospects for their environmental quality to secure sustainable forest management. Life-cycle methodology was developed and applied to assess environmental burdens and impacts of the logging and sawmill residues throughout the whole fuel chain from the forest to energy production. According to the study, the energy efficiencies of the forest chip systems are quite high. Net CO 2 emissions of the systems are low owing to the low input of external primary energy required to operate the systems. Although wood energy is renewable, it has many similarities with fossil fuels, e.g. as the emissions of the conversion phase are significant

  12. Selective logging: do rates of forest turnover in stems, species composition and functional traits decrease with time since disturbance? - A 45 year perspective.

    Science.gov (United States)

    Osazuwa-Peters, Oyomoare L; Jiménez, Iván; Oberle, Brad; Chapman, Colin A; Zanne, Amy E

    2015-12-01

    Selective logging, the targeted harvesting of timber trees in a single cutting cycle, is globally rising in extent and intensity. Short-term impacts of selective logging on tropical forests have been widely investigated, but long-term effects on temporal dynamics of forest structure and composition are largely unknown. Understanding these long-term dynamics will help determine whether tropical forests are resilient to selective logging and inform choices between competing demands of anthropogenic use versus conservation of tropical forests. Forest dynamics can be studied within the framework of succession theory, which predicts that temporal turnover rates should decline with time since disturbance. Here, we investigated the temporal dynamics of a tropical forest in Kibale National Park, Uganda over 45 years following selective logging. We estimated turnover rates in stems, species composition, and functional traits (wood density and diameter at breast height), using observations from four censuses in 1989, 1999, 2006, and 2013, of stems ≥ 10 cm diameter within 17 unlogged and 9 logged 200 × 10 m vegetation plots. We used null models to account for interdependencies among turnover rates in stems, species composition, and functional traits. We tested predictions that turnover rates should be higher and decrease with increasing time since the selective logging event in logged forest, but should be less temporally variable in unlogged forest. Overall, we found higher turnover rates in logged forest for all three attributes, but turnover rates did not decline through time in logged forest and was not less temporally variable in unlogged forest. These results indicate that successional models that assume recovery to pre-disturbance conditions are inadequate for predicting the effects of selective logging on the dynamics of the tropical forest in Kibale. Selective logging resulted in persistently higher turnover rates, which may compromise the carbon storage capacity

  13. Selective logging: do rates of forest turnover in stems, species composition and functional traits decrease with time since disturbance? – A 45 year perspective

    Science.gov (United States)

    Osazuwa-Peters, Oyomoare L.; Jiménez, Iván; Oberle, Brad; Chapman, Colin A.; Zanne, Amy E.

    2015-01-01

    Selective logging, the targeted harvesting of timber trees in a single cutting cycle, is globally rising in extent and intensity. Short-term impacts of selective logging on tropical forests have been widely investigated, but long-term effects on temporal dynamics of forest structure and composition are largely unknown. Understanding these long-term dynamics will help determine whether tropical forests are resilient to selective logging and inform choices between competing demands of anthropogenic use versus conservation of tropical forests. Forest dynamics can be studied within the framework of succession theory, which predicts that temporal turnover rates should decline with time since disturbance. Here, we investigated the temporal dynamics of a tropical forest in Kibale National Park, Uganda over 45 years following selective logging. We estimated turnover rates in stems, species composition, and functional traits (wood density and diameter at breast height), using observations from four censuses in 1989, 1999, 2006, and 2013, of stems ≥ 10 cm diameter within 17 unlogged and 9 logged 200 × 10 m vegetation plots. We used null models to account for interdependencies among turnover rates in stems, species composition, and functional traits. We tested predictions that turnover rates should be higher and decrease with increasing time since the selective logging event in logged forest, but should be less temporally variable in unlogged forest. Overall, we found higher turnover rates in logged forest for all three attributes, but turnover rates did not decline through time in logged forest and was not less temporally variable in unlogged forest. These results indicate that successional models that assume recovery to pre-disturbance conditions are inadequate for predicting the effects of selective logging on the dynamics of the tropical forest in Kibale. Selective logging resulted in persistently higher turnover rates, which may compromise the carbon storage capacity

  14. Comparative effects of oil palm and selective logging on erosion, river channels and water chemistry in Malaysian steeplands

    Science.gov (United States)

    Walsh, Rory; Nainar, Anand; Nurhidayu, Siti; Higton, Sam; Annammala, Kogilavani; Wall, Katy; Bidin, Kawi; Blake, William; Darling, Isabella

    2017-04-01

    Oil palm land-use has expanded greatly in recent decades in SE Asia and other parts of the wet tropics, including to steepland areas, where bench-terraced landscaping is involved. Retaining (and sometimes restoring) riparian forest strips and rainforest fragments on the steepest slopes have been adopted as elements of strategies designed to reduce adverse effects on runoff generation, erosion, downstream sedimentation, flooding and pollutional problems - as well as biodiversity and emissions. Results of catchment monitoring, soil erosion and sediment fingerprinting research in oil palm and selectively logged steeplands of eastern Sabah and Peninsular Malaysia are presented. The evidence indicates the greater scale and temporal persistence of effects that oil palm land-use (compared with selective logging) has had on suspended sediment dynamics, soil erosion, downstream sedimentation, channel geometry and dynamics and river pollution. The importance of (1) high densities of roads and tracks and (2) relatively impermeable bench-terraced terrain in enhancing runoff, sediment and nutrient outputs in storm events is stressed. Influences of oil palm management practices including riparian forest strips in increasing or reducing these effects are critically reviewed and ways of increasing the effectiveness of riparian forest strips are proposed. The design and rationale of current projects exploring and testing consequences of existing and proposed improved land management practices are briefly described. The key importance of involvement of people from the oil palm industry (including multinational companies, smallholders and their organizations) and Government bodies that are responsible for land-use policies and land management practices is stressed.

  15. The Results of Complex Selective Logging in Beech-Hornbeam Tree Stands of the Greater Caucasus in Azerbaijan

    Directory of Open Access Journals (Sweden)

    A. B. Yakhyaev

    2014-06-01

    Full Text Available The results of complex selective logging conducted in beech-hornbeam tree stands on the northeastern slope of the Greater Caucasus are analyzed in the paper. Experiments were carried out in two forestry districts, involving beech stands, comprising 2–3 units, with 30° slopes, in beech forests with woodruff, fescue and forb forest types. It has been revealed that for recovering the main tree species, as well as for increasing productivity and sustainability of the beech-hornbeam tree stands, which was spread out in the northern exposures, 2–3 repetitions of complex selective logging are recommended. It is recommended that in order to increase the amount of beech in the tree stand composition to 6–8 units in young stands and to 4–6 units at the slopes of south exposures, to complete 3–4 thinning operations, with the increasing beech share to 4–5 units in the upper story and in the undergrowth.

  16. Identification of contemporary selection signatures using composite log likelihood and their associations with marbling score in Korean cattle.

    Science.gov (United States)

    Ryu, Jihye; Lee, Chaeyoung

    2014-12-01

    Positive selection not only increases beneficial allele frequency but also causes augmentation of allele frequencies of sequence variants in close proximity. Signals for positive selection were detected by the statistical differences in subsequent allele frequencies. To identify selection signatures in Korean cattle, we applied a composite log-likelihood (CLL)-based method, which calculates a composite likelihood of the allelic frequencies observed across sliding windows of five adjacent loci and compares the value with the critical statistic estimated by 50,000 permutations. Data for a total of 11,799 nucleotide polymorphisms were used with 71 Korean cattle and 209 foreign beef cattle. As a result, 147 signals were identified for Korean cattle based on CLL estimates (P selected. Further genetic association analysis with 41 intragenic variants in the selection signatures with the greatest CLL for each chromosome revealed that marbling score was associated with five variants. Intensive association studies with all the selection signatures identified in this study are required to exclude signals associated with other phenotypes or signals falsely detected and thus to identify genetic markers for meat quality. © 2014 Stichting International Foundation for Animal Genetics.

  17. Selective logging in tropical forests decreases the robustness of liana-tree interaction networks to the loss of host tree species.

    Science.gov (United States)

    Magrach, Ainhoa; Senior, Rebecca A; Rogers, Andrew; Nurdin, Deddy; Benedick, Suzan; Laurance, William F; Santamaria, Luis; Edwards, David P

    2016-03-16

    Selective logging is one of the major drivers of tropical forest degradation, causing important shifts in species composition. Whether such changes modify interactions between species and the networks in which they are embedded remain fundamental questions to assess the 'health' and ecosystem functionality of logged forests. We focus on interactions between lianas and their tree hosts within primary and selectively logged forests in the biodiversity hotspot of Malaysian Borneo. We found that lianas were more abundant, had higher species richness, and different species compositions in logged than in primary forests. Logged forests showed heavier liana loads disparately affecting slow-growing tree species, which could exacerbate the loss of timber value and carbon storage already associated with logging. Moreover, simulation scenarios of host tree local species loss indicated that logging might decrease the robustness of liana-tree interaction networks if heavily infested trees (i.e. the most connected ones) were more likely to disappear. This effect is partially mitigated in the short term by the colonization of host trees by a greater diversity of liana species within logged forests, yet this might not compensate for the loss of preferred tree hosts in the long term. As a consequence, species interaction networks may show a lagged response to disturbance, which may trigger sudden collapses in species richness and ecosystem function in response to additional disturbances, representing a new type of 'extinction debt'. © 2016 The Author(s).

  18. Selective logging in tropical forests decreases the robustness of liana–tree interaction networks to the loss of host tree species

    Science.gov (United States)

    Magrach, Ainhoa; Senior, Rebecca A.; Rogers, Andrew; Nurdin, Deddy; Benedick, Suzan; Laurance, William F.; Santamaria, Luis; Edwards, David P.

    2016-01-01

    Selective logging is one of the major drivers of tropical forest degradation, causing important shifts in species composition. Whether such changes modify interactions between species and the networks in which they are embedded remain fundamental questions to assess the ‘health’ and ecosystem functionality of logged forests. We focus on interactions between lianas and their tree hosts within primary and selectively logged forests in the biodiversity hotspot of Malaysian Borneo. We found that lianas were more abundant, had higher species richness, and different species compositions in logged than in primary forests. Logged forests showed heavier liana loads disparately affecting slow-growing tree species, which could exacerbate the loss of timber value and carbon storage already associated with logging. Moreover, simulation scenarios of host tree local species loss indicated that logging might decrease the robustness of liana–tree interaction networks if heavily infested trees (i.e. the most connected ones) were more likely to disappear. This effect is partially mitigated in the short term by the colonization of host trees by a greater diversity of liana species within logged forests, yet this might not compensate for the loss of preferred tree hosts in the long term. As a consequence, species interaction networks may show a lagged response to disturbance, which may trigger sudden collapses in species richness and ecosystem function in response to additional disturbances, representing a new type of ‘extinction debt’. PMID:26936241

  19. Nest-site selection by cavity-nesting birds in relation to postfire salvage logging

    Science.gov (United States)

    Victoria A. Saab; Robin E. Russell; Jonathan G. Dudley

    2009-01-01

    Large wildfire events in coniferous forests of the western United States are often followed by postfire timber harvest. The long-term impacts of postfire timber harvest on fire-associated cavity-nesting bird species are not well documented. We studied nest-site selection by cavity-nesting birds over a 10-year period (1994-2003), representing 1-11 years after fire, on...

  20. Selection of sugarcane mutants with resistance to red-rot disease, water-logging and delayed/non-flowering

    Energy Technology Data Exchange (ETDEWEB)

    Shaikh, M A.Q.; Shamsuzzaman, K M; Majid, M A; Howlider, M A.R.; Islam, M M [Institute of Nuclear Agriculture, Mymensingh (Bangladesh)

    1997-07-01

    Three batches of sugarcane cuttings were irradiated with gamma-rays in three different years for isolating mutants for delayed flowering, resistance to red-rot disease and water-logged conditions. In the first batch cuttings of cvs. `Isd-2/54`, `Latarijaba` and `Nagarbari` were irradiated with 20-40 Gy gamma-rays. In M{sub 1} V{sub 4} generation, 2,114 canes selected from inoculated M{sub 1}V{sub 3} generation, were re-inoculated with red-hot pathogen. Of these, four canes were resistant and 64 canes were moderately resistant to the disease. The M{sub 1}V{sub 5} generation of the selected clones was grown at two locations for selection. In the second batch, cuttings of cvs. `Isd-16`, `Isd-2/54`, `Nagarbari` and `Latarijaba` were irradiated with 20-60 Gy gamma-rays. The irradiated material was divided into three lots and each lot was put under different selection pressure. For isolating mutants with resistance to red-rot disease, 15,104 canes were artificially inoculated in the M{sub 1}V{sub 3}. Among these, one clone was resistant and 16 were moderately resistant. Of the 10,000 M{sub 1}V{sub 3} canes, grown under water-logged condition and selected for greenness of leaf at harvest, 38 canes were reasonably tolerant. For selecting late flowering mutants, about 8,500 canes were left in a field for a month after normal harvest; of these five showed late flowering. These mutants were grown for further selection in the M{sub 1}V{sub 4}. To screen out non-flowering canes, cvs. `I-291/87`, an early flowering types, and `I525/85`, a late flowering type were irradiated with 20-40 Gy gamma rays. M{sub 1}V{sub 3} generation has been grown in the field. (author). 13 refs, 6 tabs.

  1. Impacts of Airborne Lidar Pulse Density on Estimating Biomass Stocks and Changes in a Selectively Logged Tropical Forest

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Silva

    2017-10-01

    Full Text Available Airborne lidar is a technology well-suited for mapping many forest attributes, including aboveground biomass (AGB stocks and changes in selective logging in tropical forests. However, trade-offs still exist between lidar pulse density and accuracy of AGB estimates. We assessed the impacts of lidar pulse density on the estimation of AGB stocks and changes using airborne lidar and field plot data in a selectively logged tropical forest located near Paragominas, Pará, Brazil. Field-derived AGB was computed at 85 square 50 × 50 m plots in 2014. Lidar data were acquired in 2012 and 2014, and for each dataset the pulse density was subsampled from its original density of 13.8 and 37.5 pulses·m−2 to lower densities of 12, 10, 8, 6, 4, 2, 0.8, 0.6, 0.4 and 0.2 pulses·m−2. For each pulse density dataset, a power-law model was developed to estimate AGB stocks from lidar-derived mean height and corresponding changes between the years 2012 and 2014. We found that AGB change estimates at the plot level were only slightly affected by pulse density. However, at the landscape level we observed differences in estimated AGB change of >20 Mg·ha−1 when pulse density decreased from 12 to 0.2 pulses·m−2. The effects of pulse density were more pronounced in areas of steep slope, especially when the digital terrain models (DTMs used in the lidar derived forest height were created from reduced pulse density data. In particular, when the DTM from high pulse density in 2014 was used to derive the forest height from both years, the effects on forest height and the estimated AGB stock and changes did not exceed 20 Mg·ha−1. The results suggest that AGB change can be monitored in selective logging in tropical forests with reasonable accuracy and low cost with low pulse density lidar surveys if a baseline high-quality DTM is available from at least one lidar survey. We recommend the results of this study to be considered in developing projects and national

  2. Geophysical log analysis of selected test and residential wells at the Shenandoah Road National Superfund Site, East Fishkill, Dutchess County, New York

    Science.gov (United States)

    Reynolds, Richard J.; Anderson, J. Alton; Williams, John H.

    2015-01-01

    The U.S. Geological Survey collected and analyzed geophysical logs from 20 test wells and 23 residential wells at the Shenandoah Road National Superfund Site in East Fishkill, New York, from 2006 through 2010 as part of an Interagency Agreement to provide hydrogeologic technical support to the U.S. Environmental Protection Agency, Region 2. The geophysical logs collected include caliper, gamma, acoustic and optical televiewer, deviation, electromagnetic-induction, magnetic-susceptibility, fluid-property, and flow under ambient and pumped conditions. The geophysical logs were analyzed along with single-well aquifer test data and drilling logs to characterize the lithology, fabric, fractures, and flow zones penetrated by the wells. The results of the geophysical log analysis were used as part of the hydrogeologic characterization of the site and in the design of discrete-zone monitoring installations in the test wells and selected residential wells.

  3. Remote Sensing of Leaf Area Index from LiDAR Height Percentile Metrics and Comparison with MODIS Product in a Selectively Logged Tropical Forest Area in Eastern Amazonia

    Directory of Open Access Journals (Sweden)

    Yonghua Qu

    2018-06-01

    Full Text Available Leaf area index (LAI is an important parameter to describe the capacity of forests to intercept light and thus affects the microclimate and photosynthetic capacity of canopies. In general, tropical forests have a higher leaf area index and it is a challenge to estimate LAI in a forest with a very dense canopy. In this study, it is assumed that the traditional Light Detection and Ranging (LiDAR-derived fractional vegetation cover (fCover has weak relationship with leaf area index in a dense forest. We propose a partial least squares (PLS regression model using the height percentile metrics derived from airborne LiDAR data to estimate the LAI of a dense forest. Ground inventory and airborne LiDAR data collected in a selectively logged tropical forest area in Eastern Amazonia are used to map LAI from the plot level to the landscape scale. The results indicate that the fCover, derived from the first return or the last return, has no significant correlations with the ground-based LAI. The PLS model evaluated by the leave-one-out validation shows that the estimated LAI is significantly correlated with the ground-based LAI with an R2 of 0.58 and a root mean square error (RMSE of 1.13. A data comparison indicates that the Moderate Resolution Imaging Spectrometer (MODIS LAI underestimates the landscape-level LAI by about 22%. The MODIS quality control data show that in the selected tile, the cloud state is not the primary factor affecting the MODIS LAI performance; rather, the LAI from the main radiative transfer (RT algorithm contributes much to the underestimation of the LAI in the tropical forest. In addition, the results show that the LiDAR-based LAI has a better response to the logging activities than the MODIS-based LAI, and that the leaf area reduction caused by logging is about 13%. In contrast, the MODIS-based LAI exhibits no apparent spatial correlation with the LiDAR-based LAI. It is suggested that the main algorithm of MODIS should be

  4. Long-term impacts of selective logging on two Amazonian tree species with contrasting ecological and reproductive characteristics: inferences from Eco-gene model simulations.

    Science.gov (United States)

    Vinson, C C; Kanashiro, M; Sebbenn, A M; Williams, T C R; Harris, S A; Boshier, D H

    2015-08-01

    The impact of logging and subsequent recovery after logging is predicted to vary depending on specific life history traits of the logged species. The Eco-gene simulation model was used to evaluate the long-term impacts of selective logging over 300 years on two contrasting Brazilian Amazon tree species, Dipteryx odorata and Jacaranda copaia. D. odorata (Leguminosae), a slow growing climax tree, occurs at very low densities, whereas J. copaia (Bignoniaceae) is a fast growing pioneer tree that occurs at high densities. Microsatellite multilocus genotypes of the pre-logging populations were used as data inputs for the Eco-gene model and post-logging genetic data was used to verify the output from the simulations. Overall, under current Brazilian forest management regulations, there were neither short nor long-term impacts on J. copaia. By contrast, D. odorata cannot be sustainably logged under current regulations, a sustainable scenario was achieved by increasing the minimum cutting diameter at breast height from 50 to 100 cm over 30-year logging cycles. Genetic parameters were only slightly affected by selective logging, with reductions in the numbers of alleles and single genotypes. In the short term, the loss of alleles seen in J. copaia simulations was the same as in real data, whereas fewer alleles were lost in D. odorata simulations than in the field. The different impacts and periods of recovery for each species support the idea that ecological and genetic information are essential at species, ecological guild or reproductive group levels to help derive sustainable management scenarios for tropical forests.

  5. Inter-tester reliability of selected clinical tests for long-lasting temporomandibular disorders.

    Science.gov (United States)

    Julsvoll, Elisabeth Heggem; Vøllestad, Nina Køpke; Opseth, Gro; Robinson, Hilde Stendal

    2017-09-01

    Clinical tests used to examine patients with temporomandibular disorders vary in methodological quality, and some are not tested for reliability. The purpose of this cross-sectional study was to evaluate inter-tester reliability of clinical tests and a cluster of tests used to examine patients with long-lasting temporomandibular disorders. Forty patients with pain in the temporomandibular area treated by health-professionals were included. They were between 18-70 years, had 65 symptomatic (33 right/32 left) and 15 asymptomatic joints. Two manual therapists examined all participants with selected tests. Percentage agreement and the kappa coefficient ( k ) with 95% confidence interval (CI) were used to evaluate the tests with categorical outcomes. For tests with continuous outcomes, the relative inter-tester reliability was assessed by the intraclass-correlation-coefficient (ICC 3,1 , 95% CI) and the absolute reliability was calculated by the smallest detectable change (SDC). The best reliability among single tests was found for the dental stick test, the joint-sound test ( k  = 0.80-1.0) and range of mouth-opening (ICC 3,1 (95% CI) = 0.97 (0.95-0.98) and SDC = 4 mm). The reliability of cluster of tests was excellent with both four and five positive tests out of seven. The reliability was good to excellent for the clinical tests and the cluster of tests when performed by experienced therapists. The tests are feasible for use in the clinical setting. They require no advanced equipment and are easy to perform.

  6. Borehole logging

    International Nuclear Information System (INIS)

    Olsen, H.

    1995-01-01

    Numerous ground water investigations have been accomplished by means of borehole logging. Borehole logging can be applied to establish new water recovery wells, to control the existing water producing wells and source areas and to estimate ground water quality. (EG)

  7. Strong selection during the last millennium for African ancestry in the admixed population of Madagascar.

    Science.gov (United States)

    Pierron, Denis; Heiske, Margit; Razafindrazaka, Harilanto; Pereda-Loth, Veronica; Sanchez, Jazmin; Alva, Omar; Arachiche, Amal; Boland, Anne; Olaso, Robert; Deleuze, Jean-Francois; Ricaut, Francois-Xavier; Rakotoarisoa, Jean-Aimé; Radimilahy, Chantal; Stoneking, Mark; Letellier, Thierry

    2018-03-02

    While admixed populations offer a unique opportunity to detect selection, the admixture in most of the studied populations occurred too recently to produce conclusive signals. By contrast, Malagasy populations originate from admixture between Asian and African populations that occurred ~27 generations ago, providing power to detect selection. We analyze local ancestry across the genomes of 700 Malagasy and identify a strong signal of recent positive selection, with an estimated selection coefficient >0.2. The selection is for African ancestry and affects 25% of chromosome 1, including the Duffy blood group gene. The null allele at this gene provides resistance to Plasmodium vivax malaria, and previous studies have suggested positive selection for this allele in the Malagasy population. This selection event also influences numerous other genes implicated in immunity, cardiovascular diseases, and asthma and decreases the Asian ancestry genome-wide by 10%, illustrating the role played by selection in recent human history.

  8. Estimating the population density of the Asian tapir (Tapirus indicus) in a selectively logged forest in Peninsular Malaysia.

    Science.gov (United States)

    Rayan, D Mark; Mohamad, Shariff Wan; Dorward, Leejiah; Aziz, Sheema Abdul; Clements, Gopalasamy Reuben; Christopher, Wong Chai Thiam; Traeholt, Carl; Magintan, David

    2012-12-01

    The endangered Asian tapir (Tapirus indicus) is threatened by large-scale habitat loss, forest fragmentation and increased hunting pressure. Conservation planning for this species, however, is hampered by a severe paucity of information on its ecology and population status. We present the first Asian tapir population density estimate from a camera trapping study targeting tigers in a selectively logged forest within Peninsular Malaysia using a spatially explicit capture-recapture maximum likelihood based framework. With a trap effort of 2496 nights, 17 individuals were identified corresponding to a density (standard error) estimate of 9.49 (2.55) adult tapirs/100 km(2) . Although our results include several caveats, we believe that our density estimate still serves as an important baseline to facilitate the monitoring of tapir population trends in Peninsular Malaysia. Our study also highlights the potential of extracting vital ecological and population information for other cryptic individually identifiable animals from tiger-centric studies, especially with the use of a spatially explicit capture-recapture maximum likelihood based framework. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

  9. The impact of selective-logging and forest clearance for oil palm on fungal communities in Borneo.

    Science.gov (United States)

    Kerfahi, Dorsaf; Tripathi, Binu M; Lee, Junghoon; Edwards, David P; Adams, Jonathan M

    2014-01-01

    Tropical forests are being rapidly altered by logging, and cleared for agriculture. Understanding the effects of these land use changes on soil fungi, which play vital roles in the soil ecosystem functioning and services, is a major conservation frontier. Using 454-pyrosequencing of the ITS1 region of extracted soil DNA, we compared communities of soil fungi between unlogged, once-logged, and twice-logged rainforest, and areas cleared for oil palm, in Sabah, Malaysia. Overall fungal community composition differed significantly between forest and oil palm plantation. The OTU richness and Chao 1 were higher in forest, compared to oil palm plantation. As a proportion of total reads, Basidiomycota were more abundant in forest soil, compared to oil palm plantation soil. The turnover of fungal OTUs across space, true β-diversity, was also higher in forest than oil palm plantation. Ectomycorrhizal (EcM) fungal abundance was significantly different between land uses, with highest relative abundance (out of total fungal reads) observed in unlogged forest soil, lower abundance in logged forest, and lowest in oil palm. In their entirety, these results indicate a pervasive effect of conversion to oil palm on fungal community structure. Such wholesale changes in fungal communities might impact the long-term sustainability of oil palm agriculture. Logging also has more subtle long term effects, on relative abundance of EcM fungi, which might affect tree recruitment and nutrient cycling. However, in general the logged forest retains most of the diversity and community composition of unlogged forest.

  10. Selective bird predation on the peppered moth: the last experiment of Michael Majerus.

    Science.gov (United States)

    Cook, L M; Grant, B S; Saccheri, I J; Mallet, J

    2012-08-23

    Colour variation in the peppered moth Biston betularia was long accepted to be under strong natural selection. Melanics were believed to be fitter than pale morphs because of lower predation at daytime resting sites on dark, sooty bark. Melanics became common during the industrial revolution, but since 1970 there has been a rapid reversal, assumed to have been caused by predators selecting against melanics resting on today's less sooty bark. Recently, these classical explanations of melanism were attacked, and there has been general scepticism about birds as selective agents. Experiments and observations were accordingly carried out by Michael Majerus to address perceived weaknesses of earlier work. Unfortunately, he did not live to publish the results, which are analysed and presented here by the authors. Majerus released 4864 moths in his six-year experiment, the largest ever attempted for any similar study. There was strong differential bird predation against melanic peppered moths. Daily selection against melanics (s ≈ 0.1) was sufficient in magnitude and direction to explain the recent rapid decline of melanism in post-industrial Britain. These data provide the most direct evidence yet to implicate camouflage and bird predation as the overriding explanation for the rise and fall of melanism in moths.

  11. Analysis of selected microflares observed by SphinX over the last minimum of solar activity

    Science.gov (United States)

    Siarkowski, Marek; Sylwester, Janusz; Sylwester, Barbara; Gryciuk, Magdalena

    The Solar Photometer in X-rays (SphinX) was designed to observe soft X-ray solar emission in the energy range between 1 keV and 15 keV with the resolution better than 0.5 keV. The instrument operated from February until November 2009 aboard CORONAS-Photon satellite, during the phase of exceptionally low minimum of solar activity. Here we use SphinX data for analysis of selected microflare-class events. We selected events of unusual lightcurves or location. Our study involves determination of temporal characteristics (times of start, maximum and end of flares) and analysis of physical conditions in flaring plasma (temperature, emission measure). Dedicated method has been used in order to remove emission not related to flare. Supplementary information about morphology and evolution of investigated events has been derived from the analysis of XRT/Hinode and SECCHI /STEREO images.

  12. Analysis of borehole-radar reflection logs from selected HC boreholes at the Project Shoal area, Churchill County, Nevada; TOPICAL

    International Nuclear Information System (INIS)

    Lane, J.W. Jr.; Joesten, P.K.; Pohll, Greg; Mihevic, Todd

    2001-01-01

    Single-hole borehole-radar reflection logs were collected and interpreted in support of a study to characterize ground-water flow and transport at the Project Shoal Area (PSA) in Churchill County, Nevada. Radar logging was conducted in six boreholes using 60-MHz omni-directional electric-dipole antennas and a 60-MHz magnetic-dipole directional receiving antenna. Radar data from five boreholes were interpreted to identify the location, orientation, estimated length, and spatial continuity of planar reflectors present in the logs. The overall quality of the radar data is marginal and ranges from very poor to good. Twenty-seven reflectors were interpreted from the directional radar reflection logs. Although the range of orientation interpreted for the reflectors is large, a significant number of reflectors strike northeast-southwest and east-west to slightly northwest-southeast. Reflectors are moderate to steeply dipping and reflector length ranged from less than 7 m to more than 133 m. Qualitative scores were assigned to each reflector to provide a sense of the spatial continuity of the reflector and the characteristics of the field data relative to an ideal planar reflector (orientation score). The overall orientation scores are low, which reflects the general data quality, but also indicates that the properties of most reflectors depart from the ideal planar case. The low scores are consistent with reflections from fracture zones that contain numerous, closely spaced, sub-parallel fractures. Interpretation of borehole-radar direct-wave velocity and amplitude logs identified several characteristics of the logged boreholes: (1) low-velocity zones correlate with decreased direct-wave amplitude, indicating the presence of fracture zones; (2) direct-wave amplitude increases with depth in three of the boreholes, suggesting an increase in electrical resistivity with depth resulting from changes in mineral assemblage or from a decrease in the specific conductance of ground

  13. Analysis of borehole-radar reflection logs from selected HC boreholes at the Project Shoal area, Churchill County, Nevada

    Science.gov (United States)

    Lane, J.W.; Joesten, P.K.; Pohll, G.M.; Mihevic, Todd

    2001-01-01

    Single-hole borehole-radar reflection logs were collected and interpreted in support of a study to characterize ground-water flow and transport at the Project Shoal Area (PSA) in Churchill County, Nevada. Radar logging was conducted in six boreholes using 60-MHz omni-directional electric-dipole antennas and a 60-MHz magnetic-dipole directional receiving antenna.Radar data from five boreholes were interpreted to identify the location, orientation, estimated length, and spatial continuity of planar reflectors present in the logs. The overall quality of the radar data is marginal and ranges from very poor to good. Twenty-seven reflectors were interpreted from the directional radar reflection logs. Although the range of orientation interpreted for the reflectors is large, a significant number of reflectors strike northeast-southwest and east-west to slightly northwest-southeast. Reflectors are moderate to steeply dipping and reflector length ranged from less than 7 m to more than 133 m.Qualitative scores were assigned to each reflector to provide a sense of the spatial continuity of the reflector and the characteristics of the field data relative to an ideal planar reflector (orientation score). The overall orientation scores are low, which reflects the general data quality, but also indicates that the properties of most reflectors depart from the ideal planar case. The low scores are consistent with reflections from fracture zones that contain numerous, closely spaced, sub-parallel fractures.Interpretation of borehole-radar direct-wave velocity and amplitude logs identified several characteristics of the logged boreholes: (1) low-velocity zones correlate with decreased direct-wave amplitude, indicating the presence of fracture zones; (2) direct-wave amplitude increases with depth in three of the boreholes, suggesting an increase in electrical resistivity with depth resulting from changes in mineral assemblage or from a decrease in the specific conductance of ground

  14. Hardwood log grades and lumber grade yields for factory lumber logs

    Science.gov (United States)

    Leland F. Hanks; Glenn L. Gammon; Robert L. Brisbin; Everette D. Rast

    1980-01-01

    The USDA Forest Service Standard Grades for Hardwood Factory Lumber Logs are described, and lumber grade yields for 16 species and 2 species groups are presented by log grade and log diameter. The grades enable foresters, log buyers, and log sellers to select and grade those log suitable for conversion into standard factory grade lumber. By using the apropriate lumber...

  15. An integrated remote sensing and GIS approach for monitoring areas affected by selective logging: A case study in northern Mato Grosso, Brazilian Amazon

    Science.gov (United States)

    Grecchi, Rosana Cristina; Beuchle, René; Shimabukuro, Yosio Edemir; Aragão, Luiz E. O. C.; Arai, Egidio; Simonetti, Dario; Achard, Frédéric

    2017-09-01

    Forest cover disturbances due to processes such as logging and forest fires are a widespread issue especially in the tropics, and have heavily affected forest biomass and functioning in the Brazilian Amazon in the past decades. Satellite remote sensing has played a key role for assessing logging activities in this region; however, there are still remaining challenges regarding the quantification and monitoring of these processes affecting forested lands. In this study, we propose a new method for monitoring areas affected by selective logging in one of the hotspots of Mato Grosso state in the Brazilian Amazon, based on a combination of object-based and pixel-based classification approaches applied on remote sensing data. Logging intensity and changes over time are assessed within grid cells of 300 m × 300 m spatial resolution. Our method encompassed three main steps: (1) mapping forest/non-forest areas through an object-based classification approach applied to a temporal series of Landsat images during the period 2000-2015, (2) mapping yearly logging activities from soil fraction images on the same Landsat data series, and (3) integrating information from previous steps within a regular grid-cell of 300 m × 300 m in order to monitor disturbance intensities over this 15-years period. The overall accuracy of the baseline forest/non-forest mask (year 2000) and of the undisturbed vs disturbed forest (for selected years) were 93% and 84% respectively. Our results indicate that annual forest disturbance rates, mainly due to logging activities, were higher than annual deforestation rates during the whole period of study. The deforested areas correspond to circa 25% of the areas affected by forest disturbances. Deforestation rates were highest from 2001 to 2005 and then decreased considerably after 2006. In contrast, the annual forest disturbance rates show high temporal variability with a slow decrease over the 15-year period, resulting in a significant increase of the

  16. An integrated remote sensing and GIS approach for monitoring areas affected by selective logging: A case study in northern Mato Grosso, Brazilian Amazon.

    Science.gov (United States)

    Grecchi, Rosana Cristina; Beuchle, René; Shimabukuro, Yosio Edemir; Aragão, Luiz E O C; Arai, Egidio; Simonetti, Dario; Achard, Frédéric

    2017-09-01

    Forest cover disturbances due to processes such as logging and forest fires are a widespread issue especially in the tropics, and have heavily affected forest biomass and functioning in the Brazilian Amazon in the past decades. Satellite remote sensing has played a key role for assessing logging activities in this region; however, there are still remaining challenges regarding the quantification and monitoring of these processes affecting forested lands. In this study, we propose a new method for monitoring areas affected by selective logging in one of the hotspots of Mato Grosso state in the Brazilian Amazon, based on a combination of object-based and pixel-based classification approaches applied on remote sensing data. Logging intensity and changes over time are assessed within grid cells of 300 m × 300 m spatial resolution. Our method encompassed three main steps: (1) mapping forest/non-forest areas through an object-based classification approach applied to a temporal series of Landsat images during the period 2000-2015, (2) mapping yearly logging activities from soil fraction images on the same Landsat data series, and (3) integrating information from previous steps within a regular grid-cell of 300 m × 300 m in order to monitor disturbance intensities over this 15-years period. The overall accuracy of the baseline forest/non-forest mask (year 2000) and of the undisturbed vs disturbed forest (for selected years) were 93% and 84% respectively. Our results indicate that annual forest disturbance rates, mainly due to logging activities, were higher than annual deforestation rates during the whole period of study. The deforested areas correspond to circa 25% of the areas affected by forest disturbances. Deforestation rates were highest from 2001 to 2005 and then decreased considerably after 2006. In contrast, the annual forest disturbance rates show high temporal variability with a slow decrease over the 15-year period, resulting in a significant increase

  17. Early Postnatal Manganese Exposure Causes Lasting Impairment of Selective and Focused Attention and Arousal Regulation in Adult Rats

    Science.gov (United States)

    Beaudin, Stephane A.; Strupp, Barbara J.; Strawderman, Myla; Smith, Donald R.

    2016-01-01

    Background: Studies in children and adolescents have associated early developmental manganese (Mn) exposure with inattention, impulsivity, hyperactivity, and oppositional behaviors, but causal inferences are precluded by the correlational nature of the data and generally limited control for potential confounders. Objectives: To determine whether early postnatal oral Mn exposure causes lasting attentional and impulse control deficits in adulthood, and whether continued lifelong Mn exposure exacerbates these effects, using a rat model of environmental Mn exposure. Methods: Neonates were exposed orally to 0, 25 or 50 mg Mn/kg/day during early postnatal life (PND 1–21) or throughout life from PND 1 until the end of the study. In adulthood, the animals were tested on a series of learning and attention tasks using the five-choice serial reaction time task. Results: Early postnatal Mn exposure caused lasting attentional dysfunction due to impairments in attentional preparedness, selective attention, and arousal regulation, whereas associative ability (learning) and impulse control were spared. The presence and severity of these deficits varied with the dose and duration of Mn exposure. Conclusions: This study is the first to show that developmental Mn exposure can cause lasting impairments in focused and selective attention and arousal regulation, and to identify the specific nature of the impairments. Given the importance of attention and arousal regulation in cognitive functioning, these findings substantiate concerns about the adverse effects of developmental Mn exposure in humans. Citation: Beaudin SA, Strupp BJ, Strawderman M, Smith DR. 2017. Early postnatal manganese exposure causes lasting impairment of selective and focused attention and arousal regulation in adult rats. Environ Health Perspect 125:230–237; http://dx.doi.org/10.1289/EHP258 PMID:27384154

  18. Early Postnatal Manganese Exposure Causes Lasting Impairment of Selective and Focused Attention and Arousal Regulation in Adult Rats.

    Science.gov (United States)

    Beaudin, Stephane A; Strupp, Barbara J; Strawderman, Myla; Smith, Donald R

    2017-02-01

    Studies in children and adolescents have associated early developmental manganese (Mn) exposure with inattention, impulsivity, hyperactivity, and oppositional behaviors, but causal inferences are precluded by the correlational nature of the data and generally limited control for potential confounders. To determine whether early postnatal oral Mn exposure causes lasting attentional and impulse control deficits in adulthood, and whether continued lifelong Mn exposure exacerbates these effects, using a rat model of environmental Mn exposure. Neonates were exposed orally to 0, 25 or 50 mg Mn/kg/day during early postnatal life (PND 1-21) or throughout life from PND 1 until the end of the study. In adulthood, the animals were tested on a series of learning and attention tasks using the five-choice serial reaction time task. Early postnatal Mn exposure caused lasting attentional dysfunction due to impairments in attentional preparedness, selective attention, and arousal regulation, whereas associative ability (learning) and impulse control were spared. The presence and severity of these deficits varied with the dose and duration of Mn exposure. This study is the first to show that developmental Mn exposure can cause lasting impairments in focused and selective attention and arousal regulation, and to identify the specific nature of the impairments. Given the importance of attention and arousal regulation in cognitive functioning, these findings substantiate concerns about the adverse effects of developmental Mn exposure in humans. Citation: Beaudin SA, Strupp BJ, Strawderman M, Smith DR. 2017. Early postnatal manganese exposure causes lasting impairment of selective and focused attention and arousal regulation in adult rats. Environ Health Perspect 125:230-237; http://dx.doi.org/10.1289/EHP258.

  19. Systematic detection of positive selection in the human-pathogen interactome and lasting effects on infectious disease susceptibility.

    Directory of Open Access Journals (Sweden)

    Erik Corona

    Full Text Available Infectious disease has shaped the natural genetic diversity of humans throughout the world. A new approach to capture positive selection driven by pathogens would provide information regarding pathogen exposure in distinct human populations and the constantly evolving arms race between host and disease-causing agents. We created a human pathogen interaction database and used the integrated haplotype score (iHS to detect recent positive selection in genes that interact with proteins from 26 different pathogens. We used the Human Genome Diversity Panel to identify specific populations harboring pathogen-interacting genes that have undergone positive selection. We found that human genes that interact with 9 pathogen species show evidence of recent positive selection. These pathogens are Yersenia pestis, human immunodeficiency virus (HIV 1, Zaire ebolavirus, Francisella tularensis, dengue virus, human respiratory syncytial virus, measles virus, Rubella virus, and Bacillus anthracis. For HIV-1, GWAS demonstrate that some naturally selected variants in the host-pathogen protein interaction networks continue to have functional consequences for susceptibility to these pathogens. We show that selected human genes were enriched for HIV susceptibility variants (identified through GWAS, providing further support for the hypothesis that ancient humans were exposed to lentivirus pandemics. Human genes in the Italian, Miao, and Biaka Pygmy populations that interact with Y. pestis show significant signs of selection. These results reveal some of the genetic footprints created by pathogens in the human genome that may have left lasting marks on susceptibility to infectious disease.

  20. Selective mutism: a review and integration of the last 15 years.

    Science.gov (United States)

    Viana, Andres G; Beidel, Deborah C; Rabian, Brian

    2009-02-01

    Selective mutism (SM) is a rare childhood disorder characterized by a lack of speech in one or more settings in which speaking is socially expected. A comprehensive and uniform theory about the etiology, assessment, and treatment of SM does not exist. Historically, varying definitions and criteria have been applied to children with SM, therefore making comparisons between studies somewhat difficult. Accumulating findings on the phenomenology of SM point to a complex and multidetermined etiology. Developmental psychopathology represents a useful heuristic for conceptualization of SM and serves as an integrative framework for organizing the sometimes disparate findings that permeate the SM literature. The purpose of this review is to summarize the literature on SM, including phenomenology, assessment, and treatment, with the main goals of clarifying its clinical presentation, offering a theoretical understanding of SM from a developmental psychopathology perspective, and highlighting both research and practice gaps that may exist. Recommendations for future research are made with the goal of expanding the current knowledge base on the etiology of SM.

  1. Recovery after 25 years of the tree and palms species diversity on a selectively logged forest in a Venezuelan lowland ecosystem

    Energy Technology Data Exchange (ETDEWEB)

    Lozada, J.R.; Arends, E.; Sánchez, D.; Villarreal, A.; Guevara, J.; Soriano, P.; Costa, M.

    2016-07-01

    Aim of the study: We evaluate palm and tree species diversity in a floodplain forest and the changes affecting the plots subjected to different intensities of selective logging. Area of study: The western alluvial plains of Venezuela. Materials and Methods: A randomized complete blocks design was established 25 years ago with three felling treatments (trees with diameter greater than 20 cm, 40 cm and 60 cm). Each treatment had three replications, using 1 ha permanent plots. We have measured all trees and palms bigger than over 10 cm in diameter. The data set was used to calculate the Importance Value Index of each species, the Shannon-Wiener index, the Hill Numbers and the Chao-Sørensen index. Main results: Disturbance increases the importance value index of pioneer species like Cecropia peltata, Ochroma pyramidale and Triplaris americana. All treatments produce changes on the floristic diversity but most of them are not significant. Only the high impact treatment causes a decrease in the species richness, but after 5 year of recovery this parameter is close to its previous levels (N0= 43.5). In logged forests, species loss (9.2%) is lower than in the control plots (11.7%) and is also lower than the rate of occurrence of species input (14.6%). Research highlights: In these logged forests restoration of diversity is acceptable because is higher than 91% (Chao-Sørensen index). Selective logging, with low and medium intensity, is a disturbance that works in a similar way to natural disturbances. All the diversity indexes recovered the pre-harvest level values. (Author)

  2. Why Does Romania Have a Negative Selection in Parliamentary Elections? An Analysis of the Recruitment and Selection System During the Last Three Legislative Terms

    Directory of Open Access Journals (Sweden)

    Ioana MUNTEAN

    2016-06-01

    Full Text Available This paper considers theoretical perspectives on the recruitment and selection of political party candidates, in order to analyze the recruitment and selection process of Romanian MPs during the last three legislative terms. The Romanian proportional closed-list electoral system was replaced in 2008 by a majoritarian one, with single-member districts. In the wake of this change, party selectorates have loosened the admission criteria for candidates in parliamentary elections. Selectorates started considering candidates mostly because of their financial power and notoriety, while their education was overlooked. Our analysis shows that the quality of MPs’ diplomas has decreased significantly since 2008. Romanian MPs complete their education, most frequently technical, with MA or PhD degrees. Some get a second BA in fields complementary to their activity in Parliament – such as political, administrative or social sciences. These courses are usually taken later in life, at private universities, which are characterized by easy admission and graduation. Since there is no general rule for submitting their CVs, some MPs omit mentioning the information regarding the educational bodies that issued their diplomas. Romania continues to be characterized by a heterogeneous parliamentarian elite, as opposed to solid democracies, where the elite is formed in renowned universities. The latter also share a common background and are thus rather homogenous. We consider that a successful political reform in Romania should start within the party selectorates and their selection criteria of candidates for parliamentary elections.

  3. Selection of logging-based TOC calculation methods for shale reservoirs: A case study of the Jiaoshiba shale gas field in the Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Renchun Huang

    2015-03-01

    Full Text Available Various methods are available for calculating the TOC of shale reservoirs with logging data, and each method has its unique applicability and accuracy. So it is especially important to establish a regional experimental calculation model based on a thorough analysis of their applicability. With the Upper Ordovician Wufeng Fm-Lower Silurian Longmaxi Fm shale reservoirs as an example, TOC calculation models were built by use of the improved ΔlgR, bulk density, natural gamma spectroscopy, multi-fitting and volume model methods respectively, considering the previous research results and the geologic features of the area. These models were compared based on the core data. Finally, the bulk density method was selected as the regional experimental calculation model. Field practices demonstrated that the improved ΔlgR and natural gamma spectroscopy methods are poor in accuracy; although the multi-fitting method and bulk density method have relatively high accuracy, the bulk density method is simpler and wider in application. For further verifying its applicability, the bulk density method was applied to calculate the TOC of shale reservoirs in several key wells in the Jiaoshiba shale gas field, Sichuan Basin, and the calculation accuracy was clarified with the measured data of core samples, showing that the coincidence rate of logging-based TOC calculation is up to 90.5%–91.0%.

  4. Recovery of a lowland dipterocarp forest twenty two years after selective logging at Sekundur, Gunung Leuser National Park, North Sumatra, Indonesia

    Directory of Open Access Journals (Sweden)

    Dolly - Priatna

    2006-12-01

    Full Text Available PRIATNA, D.; KARTAWINATA, K.; ABDULHADI, R. 2004. Recovery of a lowland dipterocarp forest twenty two years after selective logging at Sekundur, Gunung Leuser National Park, North Sumatra, Indonesia. Reinwardtia 12 (3: 237–255. — A permanent 2-ha plot of lowland forest selectively logged in 1978 at Sekundur, Gunung Leuser National Park, which is also a Biosphere Reserve and a World Heritage Site, North Sumatra, was established and investigated in 1982. It was re-examined in 2000, where remeasurement and reidentification of all trees with DBH 10 cm were made. The areas of gap, building and mature phases of the canopy were also measured and mapped. Within this plot, 133 species, 87 genera and 39 families were recorded, with the total number of trees of 1145 or density of 572.5/ha. Euphorbiaceae was the richest family with 18 species (13.5 % of the total and total number of trees of 248 (21.7 % of the total or density of 124 trees/ha. The most important families were Dipterocarpaceae with IV (Importance Value = 52.0, followed by Euphorbiaceae with IV = 51.8. The most prevalent species was Shorea kunstleri (Dipterocarpaceae with IV =24.4, followed by Macaranga diepenhorstii (Euphorbiaceae with IV = 12.4. They were the species with highest density, 34 trees/ha and 23.5 trees/ha, respectively. During the period of 18 years there has been no shift in the richest families, most important families and most important species. Euphorbiaceae was the richest family and Dipterocarpaceae was the most important family, with Shorea kunstleri as the most important species with highest importance value throughout the period. The number of species increased from 127 to 133 with increase in density by 36.8% , from 418.5 trees/ha to 572.5 trees/ha. The mortality was 25.57 % or 1.4 % per year. The diameter class distribution indicated that the forest recovery has not been complete. Trees were small, comprising 67.6 % with diameters of 10-20 cm and only two trees

  5. Somaclonal variation and irradiation in sugarcane calli for selection against red rot, water-logged conditions and delayed or non-flowering characters

    International Nuclear Information System (INIS)

    Samad, M.A.; Begum, S.; Majid, M.A.

    2001-01-01

    A protocol for callus induction and plant regeneration from primordial leaf culture was established in sugarcane cv. 'Isd-16'. The regenerated (R 1 ) plants were grown in field, and the subsequent propagations (R 2 -R 4 ) were screened for resistance to red rot disease and waterlogged conditions. Three clones showed moderate resistance (MR) to red rot and 3 clones were tolerant to water-logging in R 4 . In another experiment, callus cultures were irradiated with 2 to 10 Gy gamma rays. The maximum regeneration was obtained from 3 Gy treatment. Of the 768 R 1 plants, 50 survived to maturity. R 2 and R 3 populations were selected for delayed or non-flowering types. Five R 3 canes showed delayed flowering. (author)

  6. An ant-plant by-product mutualism is robust to selective logging of rain forest and conversion to oil palm plantation.

    Science.gov (United States)

    Fayle, Tom M; Edwards, David P; Foster, William A; Yusah, Kalsum M; Turner, Edgar C

    2015-06-01

    Anthropogenic disturbance and the spread of non-native species disrupt natural communities, but also create novel interactions between species. By-product mutualisms, in which benefits accrue as side effects of partner behaviour or morphology, are often non-specific and hence may persist in novel ecosystems. We tested this hypothesis for a two-way by-product mutualism between epiphytic ferns and their ant inhabitants in the Bornean rain forest, in which ants gain housing in root-masses while ferns gain protection from herbivores. Specifically, we assessed how the specificity (overlap between fern and ground-dwelling ants) and the benefits of this interaction are altered by selective logging and conversion to an oil palm plantation habitat. We found that despite the high turnover of ant species, ant protection against herbivores persisted in modified habitats. However, in ferns growing in the oil palm plantation, ant occupancy, abundance and species richness declined, potentially due to the harsher microclimate. The specificity of the fern-ant interactions was also lower in the oil palm plantation habitat than in the forest habitats. We found no correlations between colony size and fern size in modified habitats, and hence no evidence for partner fidelity feedbacks, in which ants are incentivised to protect fern hosts. Per species, non-native ant species in the oil palm plantation habitat (18 % of occurrences) were as important as native ones in terms of fern protection and contributed to an increase in ant abundance and species richness with fern size. We conclude that this by-product mutualism persists in logged forest and oil palm plantation habitats, with no detectable shift in partner benefits. Such persistence of generalist interactions in novel ecosystems may be important for driving ecosystem functioning.

  7. The contribution of large trees to total transpiration rates in a pre-montane tropical forest and its implications for selective logging practices

    Science.gov (United States)

    Orozco, G.; Moore, G. W.; Miller, G. R.

    2012-12-01

    In the humid tropics, conservationists generally prefer selective logging practices over clearcutting. Large valuable timber is removed while the remaining forest is left relatively undisturbed. However, little is known about the impact of selective logging on site water balance. Because large trees have very deep sapwood and exposed canopies, they tend to have high transpiration. The first objective was to evaluate the methods used for scaling sap flow measurements to the watershed with particular emphasis on large trees. The second objective of this study was to determine the relative contribution of large trees to site water balance. Our study was conducted in a pre-montane transitional forest at the Texas A&M University Soltis Center in north-central Costa Rica. During the period between January and July 2012, sap flux was monitored in a 30-m diameter plot within a 10-ha watershed. Two pairs of heat dissipation sensors were installed in the outer 0-20 mm of each of 15 trees selected to represent the full range of tree sizes. In six of the largest trees, depth profiles were recorded at 10-mm intervals to a depth of 60 mm using compensation heat pulse sensors. To estimate sapwood basal area of the entire watershed, a stand survey was conducted in three 30-m-diameter plots. In each plot, we measured basal area of all trees and estimated sapwood basal area from sapwood depth measured in nearly half of the trees. An estimated 36.5% of the total sapwood area in this watershed comes from the outer 20 mm of sapwood, with the remaining 63.5% of sapwood from depths deeper than 20 mm. Nearly 13% of sapwood is from depths beyond 60 mm. Sap velocity profiles indicate the highest flow rates occurred in the 0-2 cm depths, with declines of 17% and 25% in the 20-40 mm and 40-60 mm ranges, respectively. Our results demonstrate the need to measure sap velocity profiles in large tropical trees. If total transpiration had been estimated solely from the 0-20 mm heat dissipation

  8. Pulsed radiation decay logging

    International Nuclear Information System (INIS)

    Mills, W.R. Jr.

    1983-01-01

    There are provided new and improved well logging processes and systems wherein the detection of secondary radiation is accomplished during a plurality of time windows in a manner to accurately characterize the decay rate of the secondary radiation. The system comprises a well logging tool having a primary pulsed radiation source which emits repetitive time-spaced bursts of primary radiation and detector means for detecting secondary radiation resulting from the primary radiation and producing output signals in response to the detected radiation. A plurality of measuring channels are provided, each of which produces a count rate function representative of signals received from the detector means during successive time windows occurring between the primary radiation bursts. The logging system further comprises means responsive to the measuring channels for producing a plurality of functions representative of the ratios of the radiation count rates measured during adjacent pairs of the time windows. Comparator means function to compare the ratio functions and select at least one of the ratio functions to generate a signal representative of the decay rate of the secondary radiation

  9. Encyclopedia of well logging

    International Nuclear Information System (INIS)

    Desbrandes, R.

    1985-01-01

    The 16 chapters of this book aim to provide students, trainees and engineers with a manual covering all well-logging measurements ranging from drilling to productions, from oil to minerals going by way of geothermal energy. Each chapter is a summary but a bibliography is given at the end of each chapter. Well-logging during drilling, wireline logging equipment and techniques, petroleum logging, data processing of borehole data, interpretation of well-logging, sampling tools, completion and production logging, logging in relief wells to kill off uncontrolled blowouts, techniques for high temperature geothermal energy, small-scale mining and hydrology, logging with oil-base mud and finally recommended logging programs are all topics covered. There is one chapter on nuclear well-logging which is indexed separately. (UK)

  10. Impacts of extended working hours in logging

    Science.gov (United States)

    Dana Mitchell; Tom Gallagher

    2008-01-01

    Last year at the 2007 AIM in Minneapolis, MN, the authors presented the human factors impacts to consider when implementing extended working hours in the logging industry. In a continuation of this project, we have researched existing literature to identify possible actions that logging business owners can take to reduce the impact of extended working hours on their...

  11. A construction of Japanese consensus-formation model for the selection of last disposal site of high-level radioactive wastes

    International Nuclear Information System (INIS)

    Oki, Naotaka; Saigusa, Shin; Yonehara, Hidenori

    2010-01-01

    A group with Shizuoka University as the center one is promoting the investigation of the subject 'A construction of Japanese consensus - formation model for the selection of last disposal site of high-level radioactive wastes' adopted in 'Atomic Energy Fundamental Strategic Initiative' at the 20th fiscal year of Heisei, the Ministry of Education, Culture, Sports, Science and Technology. The result of this investigation is described here. (M.H.)

  12. http Log Analysis

    DEFF Research Database (Denmark)

    Bøving, Kristian Billeskov; Simonsen, Jesper

    2004-01-01

    This article documents how log analysis can inform qualitative studies concerning the usage of web-based information systems (WIS). No prior research has used http log files as data to study collaboration between multiple users in organisational settings. We investigate how to perform http log...... analysis; what http log analysis says about the nature of collaborative WIS use; and how results from http log analysis may support other data collection methods such as surveys, interviews, and observation. The analysis of log files initially lends itself to research designs, which serve to test...... hypotheses using a quantitative methodology. We show that http log analysis can also be valuable in qualitative research such as case studies. The results from http log analysis can be triangulated with other data sources and for example serve as a means of supporting the interpretation of interview data...

  13. Importance of log size on host selection and reproductive success of Ips pini (Coleoptera: Scolytidae) in ponderosa pine slash of northern Arizona and western Montana

    Science.gov (United States)

    Brytten E. Steed; Michael R. Wagner

    2004-01-01

    Pine engraver, Ips pini (Say), often use thinning slash, and their populations are known to be influenced by the condition of this material. In our study, we evaluated the importance of three log diameters (5, 10, and 20 cm) and three lengths (60, 120, and 240 cm) on various parameters of bark beetle host attack, development, and emergence....

  14. Log files for testing usability

    NARCIS (Netherlands)

    Klein Teeselink, G.; Siepe, A.H.M.; Pijper, de J.R.

    1999-01-01

    The aim of this study is to gain insight in the usefulness of log file analysis as a method to evaluate the usability of individual interface components and their influence on the usability of the overall user interface. We selected a music player as application, with four different interfaces and

  15. A comprehensive analysis of physiologically equivalent temperature changes of Iranian selected stations for the last half century

    Science.gov (United States)

    Roshan, Gholamreza; Yousefi, Robabe; Kovács, Attila; Matzarakis, Andreas

    2018-01-01

    As a preliminary and major step for land use planning of the coming years, the study of variability of the past decades' climatic conditions with comprehensive indicators is of high importance. Given the fact that one of the affected areas by climatic change includes variability of thermal comfort, this study uses the physiologically equivalent temperature (PET) to identify and evaluate bioclimatic conditions of 40 meteorological stations in Iran. In this study, PET changes for the period of 1960 to 2010 are analyzed, with the use of Mann-Kendall non-parametric test and Pearson parametric method. The study focuses particularly on the diversity in spatio-temporal distribution of Iran's bioclimatic conditions. The findings show that the mean frequency percentage of days with comfort is 12.9 % according to the total number of selected stations. The maximum and minimum frequency percentage with values of 17.4 and 10.3 belong to Kerman and Chabahar stations, respectively. The findings of long-term trend analysis for the period of 1960-2010 show that 55 % of the stations have significant increasing trend in terms of thermal comfort class based on the Pearson method, while it is 40 % based on Mann-Kendall test. The results indicate that the highest frequency of days with thermal comfort in the southern coasts of Iran relates to the end of autumn and winter, nevertheless, such ideal conditions for the coastal cities of Caspian Sea and even central stations of Iran relate to mid-spring and mid-autumn. Late summer and early autumn along with late spring can be identified as the most ideal times in the west and northwest part of Iran. In addition, the most important inhibiting factors of thermal comfort prove to be different across the regions of Iran. For instance, in the southern coasts, warm to very hot bioclimatic events and in the west and northwest regions, cold to very cold conditions turn out to be the most important inhibiting factors. When considering the variations

  16. Log N-log S in inconclusive

    Science.gov (United States)

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

    1983-01-01

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

  17. The Meaning of Logs

    NARCIS (Netherlands)

    Etalle, Sandro; Massacci, Fabio; Yautsiukhin, Artsiom

    2007-01-01

    While logging events is becoming increasingly common in computing, in communication and in collaborative work, log systems need to satisfy increasingly challenging (if not conflicting) requirements.Despite the growing pervasiveness of log systems, to date there is no high-level framework which

  18. The Meaning of Logs

    NARCIS (Netherlands)

    Etalle, Sandro; Massacci, Fabio; Yautsiukhin, Artsiom; Lambrinoudakis, Costas; Pernul, Günther; Tjoa, A Min

    While logging events is becoming increasingly common in computing, in communication and in collaborative environments, log systems need to satisfy increasingly challenging (if not conflicting) requirements. In this paper we propose a high-level framework for modeling log systems, and reasoning about

  19. Logging utilization in Idaho: Current and past trends

    Science.gov (United States)

    Eric A. Simmons; Todd A. Morgan; Erik C. Berg; Stanley J. Zarnoch; Steven W. Hayes; Mike T. Thompson

    2014-01-01

    A study of commercial timber-harvesting activities in Idaho was conducted during 2008 and 2011 to characterize current tree utilization, logging operations, and changes from previous Idaho logging utilization studies. A two-stage simple random sampling design was used to select sites and felled trees for measurement within active logging sites. Thirty-three logging...

  20. Gate-last TiN/HfO2 band edge effective work functions using low-temperature anneals and selective cladding to control interface composition

    KAUST Repository

    Hinkle, C. L.

    2012-04-09

    Silicon N-metal-oxide-semiconductor (NMOS) and P-metal-oxide-semiconductor (PMOS) band edge effective work functions and the correspondingly low threshold voltages (Vt) are demonstrated using standard fab materials and processes in a gate-last scheme employing low-temperature anneals and selective cladding layers. Al diffusion from the cladding to the TiN/HfO2interface during forming gas anneal together with low O concentration in the TiN enables low NMOS Vt. The use of non-migrating W cladding along with experimentally detected N-induced dipoles, produced by increased oxygen in the TiN, facilitates low PMOS Vt.

  1. Gate-last TiN/HfO2 band edge effective work functions using low-temperature anneals and selective cladding to control interface composition

    KAUST Repository

    Hinkle, C. L.; Galatage, R. V.; Chapman, R. A.; Vogel, E. M.; Alshareef, Husam N.; Freeman, C.; Christensen, M.; Wimmer, E.; Niimi, H.; Li-Fatou, A.; Shaw, J. B.; Chambers, J. J.

    2012-01-01

    Silicon N-metal-oxide-semiconductor (NMOS) and P-metal-oxide-semiconductor (PMOS) band edge effective work functions and the correspondingly low threshold voltages (Vt) are demonstrated using standard fab materials and processes in a gate-last scheme employing low-temperature anneals and selective cladding layers. Al diffusion from the cladding to the TiN/HfO2interface during forming gas anneal together with low O concentration in the TiN enables low NMOS Vt. The use of non-migrating W cladding along with experimentally detected N-induced dipoles, produced by increased oxygen in the TiN, facilitates low PMOS Vt.

  2. LogScope

    Science.gov (United States)

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

    2012-01-01

    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).

  3. Induction of somaclonal variation and mutations in sugarcane calli for selecting mutants with resistance to red-rot and tolerance to water-logged conditions

    International Nuclear Information System (INIS)

    Shaikh, M.A.Q.; Begum, S.; Samad, M.A.; Shmsuzzaman, K.M.

    1997-01-01

    Immature leaves of cv. 'Isd-16' of sugarcane were cultured on modified MS medium supplemented with 3.0 mg/l 2,4-D for callus induction. The calli were transferred to MS medium supplemented with 5.0 mg/l IAA and 2.0 mg/l KIN for shoot regeneration. The shoots were rooted on MS medium supplemented with 5.0 mg/1NAA and 70 g/l sucrose. The regenerated plants were screened against red-rot disease and water-logged condition in a field. Of the 368 plants inoculated with red-rot pathogen, only one was moderately resistant and two were moderately susceptible. In another set of 500 R 1 plants, six clones were tolerant to water-logged condition. Four week-old callus cultures were irradiated with doses of 2, 3, 4, 5, 6, 7, 8 and 10 Gy gamma-rays. Survival of calli decreased with increase in radiation dose and ranged from 58 to 91%. Regenerated shoots were obtained from all irradiated calli except those treated with 8 and 10 Gy. Shoot regeneration from the irradiated calli ranged from 8 to 50%, and gave 768 R 1 plants. The highest regeneration of plants was obtained from calli treated with 3 Gy. These plants are being grown in a field for screening against red-rot and water-logged conditions. (author). 10 refs, 2 tabs

  4. Induction of somaclonal variation and mutations in sugarcane calli for selecting mutants with resistance to red-rot and tolerance to water-logged conditions

    Energy Technology Data Exchange (ETDEWEB)

    Shaikh, M A.Q.; Begum, S; Samad, M A; Shmsuzzaman, K M [Bangladesh Inst. of Nuclear Agriculture, Mymensingh (Bangladesh)

    1997-07-01

    Immature leaves of cv. `Isd-16` of sugarcane were cultured on modified MS medium supplemented with 3.0 mg/l 2,4-D for callus induction. The calli were transferred to MS medium supplemented with 5.0 mg/l IAA and 2.0 mg/l KIN for shoot regeneration. The shoots were rooted on MS medium supplemented with 5.0 mg/1NAA and 70 g/l sucrose. The regenerated plants were screened against red-rot disease and water-logged condition in a field. Of the 368 plants inoculated with red-rot pathogen, only one was moderately resistant and two were moderately susceptible. In another set of 500 R{sub 1} plants, six clones were tolerant to water-logged condition. Four week-old callus cultures were irradiated with doses of 2, 3, 4, 5, 6, 7, 8 and 10 Gy gamma-rays. Survival of calli decreased with increase in radiation dose and ranged from 58 to 91%. Regenerated shoots were obtained from all irradiated calli except those treated with 8 and 10 Gy. Shoot regeneration from the irradiated calli ranged from 8 to 50%, and gave 768 R{sub 1} plants. The highest regeneration of plants was obtained from calli treated with 3 Gy. These plants are being grown in a field for screening against red-rot and water-logged conditions. (author). 10 refs, 2 tabs.

  5. Log Analysis Using Splunk Hadoop Connect

    Science.gov (United States)

    2017-06-01

    23 A. INPUT SELECTION ...Conversion Resource Consumption .............................................. 28 Figure 8. Distribution of Events in Years...running a logging service puts a performance tax on the system and may cause the degradation of performance. More thorough 8 logging will cause a

  6. Analysis of RIA standard curve by log-logistic and cubic log-logit models

    International Nuclear Information System (INIS)

    Yamada, Hideo; Kuroda, Akira; Yatabe, Tami; Inaba, Taeko; Chiba, Kazuo

    1981-01-01

    In order to improve goodness-of-fit in RIA standard analysis, programs for computing log-logistic and cubic log-logit were written in BASIC using personal computer P-6060 (Olivetti). Iterative least square method of Taylor series was applied for non-linear estimation of logistic and log-logistic. Hear ''log-logistic'' represents Y = (a - d)/(1 + (log(X)/c)sup(b)) + d As weights either 1, 1/var(Y) or 1/σ 2 were used in logistic or log-logistic and either Y 2 (1 - Y) 2 , Y 2 (1 - Y) 2 /var(Y), or Y 2 (1 - Y) 2 /σ 2 were used in quadratic or cubic log-logit. The term var(Y) represents squares of pure error and σ 2 represents estimated variance calculated using a following equation log(σ 2 + 1) = log(A) + J log(y). As indicators for goodness-of-fit, MSL/S sub(e)sup(2), CMD% and WRV (see text) were used. Better regression was obtained in case of alpha-fetoprotein by log-logistic than by logistic. Cortisol standard curve was much better fitted with cubic log-logit than quadratic log-logit. Predicted precision of AFP standard curve was below 5% in log-logistic in stead of 8% in logistic analysis. Predicted precision obtained using cubic log-logit was about five times lower than that with quadratic log-logit. Importance of selecting good models in RIA data processing was stressed in conjunction with intrinsic precision of radioimmunoassay system indicated by predicted precision. (author)

  7. Radiometric well logging instruments

    International Nuclear Information System (INIS)

    Davydov, A.V.

    1975-01-01

    The technical properties of well instruments for radioactive logging used in the radiometric logging complexes PKS-1000-1 (''Sond-1'') and PRKS-2 (''Vitok-2'') are described. The main features of the electric circuit of the measuring channels are given

  8. Power to the logs!

    CERN Multimedia

    CERN. Geneva; MACMAHON, Joseph

    2015-01-01

    Are you tired of using grep, vi and emacs to read your logs? Do you feel like you’re missing the big picture? Does the word "statistics" put a smile on your face? Then it’s time to give power to the logs!

  9. Digital mineral logging system

    International Nuclear Information System (INIS)

    West, J.B.

    1980-01-01

    A digital mineral logging system acquires data from a mineral logging tool passing through a borehole and transmits the data uphole to an electronic digital signal processor. A predetermined combination of sensors, including a deviometer, is located in a logging tool for the acquisition of the desired data as the logging tool is raised from the borehole. Sensor data in analog format is converted in the logging tool to a digital format and periodically batch transmitted to the surface at a predetermined sampling rate. An identification code is provided for each mineral logging tool, and the code is transmitted to the surface along with the sensor data. The self-identifying tool code is transmitted to the digital signal processor to identify the code against a stored list of the range of numbers assigned to that type of tool. The data is transmitted up the d-c power lines of the tool by a frequency shift key transmission technique. At the surface, a frequency shift key demodulation unit transmits the decoupled data to an asynchronous receiver interfaced to the electronic digital signal processor. During a recording phase, the signals from the logging tool are read by the electronic digital signal processor and stored for later processing. During a calculating phase, the stored data is processed by the digital signal processor and the results are outputted to a printer or plotter, or both

  10. Mariners Weather Log

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Mariners Weather Log (MWL) is a publication containing articles, news and information about marine weather events and phenomena, worldwide environmental impact...

  11. Log-inject-log in sand consolidation

    International Nuclear Information System (INIS)

    Murphy, R.P.; Spurlock, J.W.

    1977-01-01

    A method is described for gathering information for the determination of the adequacy of placement of sand consolidating plastic for sand control in oil and gas wells. The method uses a high neutron cross-section tracer which becomes part of the plastic and uses pulsed neutron logging before and after injection of the plastic. Preferably, the method uses lithium, boron, indium, and/or cadmium tracers. Boron oxide is especially useful and can be dissolved in alcohol and mixed with the plastic ingredients

  12. Elephant logging and environment

    International Nuclear Information System (INIS)

    Tin-Aung-Hla

    1995-01-01

    The natural environment comprises non-biological elements such as air, water, light, heat and biological elements of animal and plant life; all interact with each other to create an ecosystem. Human activities like over-exploitation of forest results in deforestation and desertification. This consequently changes ecological balance. Topics on: (1) history of elephants utilization; (2) elephant logging; (3) classification of elephants; (4) dragging gear; (5) elephant power; (6) elephant logging and environment, are discussed

  13. Development of regional stump-to-mill logging cost estimators

    Science.gov (United States)

    Chris B. LeDoux; John E. Baumgras

    1989-01-01

    Planning logging operations requires estimating the logging costs for the sale or tract being harvested. Decisions need to be made on equipment selection and its application to terrain. In this paper a methodology is described that has been developed and implemented to solve the problem of accurately estimating logging costs by region. The methodology blends field time...

  14. Narrating Illegal Logging Across the Globe

    DEFF Research Database (Denmark)

    Winkel, Georg; Leipold, Sina; Buhmann, Karin

    2017-01-01

    In the last decade illegal logging has triggered the attention of policy makers and scholars of international forest governance. The issue is multifaceted, involving aspects of social and environmental sustainability, development, trade, access to markets and competitiveness. A vivid academic deb...

  15. Nuclear well logging in hydrology

    International Nuclear Information System (INIS)

    1971-01-01

    they are described in detail elsewhere. The tracer techniques which have been included involve the use of well-logging methods to locate isotopic tracers inserted either in an adjacent borehole or in the same borehole as that in which the logs are made. Throughout the report, sufficient references have been selected to ensure that proven methods are adequately represented, but a comprehensive bibliography is not included. The International Atomic Energy Agency, at the request of the Coordinating Council of the International Hydrological Decade, is providing the Secretariat for the Working Group on Nuclear Techniques in Hydrology of the International Hydrological Decade (IHD). The Working Group and Secretariat have contributed to and coordinated the preparation of this report as well as an earlier more general report, Guidebook on Nuclear Techniques in Hydrology, IAEA Technical Reports Series No.91. Nuclear logging, along with other borehole geophysical methods, was adopted and developed primarily by the petroleum industry for use in exploration and developmental work. The information in this report shows that nuclear logging may also be useful in hydrology. Qualitative and under proper conditions quantitative interpretations about the physical, chemical, petrographic and hydraulic properties of formations and their contained fluids can be made from nuclear logs. The IHD Working Group on Nuclear Techniques in Hydrology, during its fourth meeting (in 1969), considered in detail the present status of nuclear logging with respect to hydrological investigations. Particularly it considered: (1) whether suitable equipment is at present available; (2) whether it could fulfil the need of hydrologists today; and (3) whether it was yet economic for use in hydrological investigations. The Working Group noted that the two main deficiencies in nuclear logging for hydrological purposes are: (1) the general lack of information in a coordinated form, and (2) the scarcity of

  16. Log4J

    CERN Document Server

    Perry, Steven

    2009-01-01

    Log4j has been around for a while now, and it seems like so many applications use it. I've used it in my applications for years now, and I'll bet you have too. But every time I need to do something with log4j I've never done before I find myself searching for examples of how to do whatever that is, and I don't usually have much luck. I believe the reason for this is that there is a not a great deal of useful information about log4j, either in print or on the Internet. The information is too simple to be of real-world use, too complicated to be distilled quickly (which is what most developers

  17. Mechanics of log calibration

    International Nuclear Information System (INIS)

    Waller, W.C.; Cram, M.E.; Hall, J.E.

    1975-01-01

    For any measurement to have meaning, it must be related to generally accepted standard units by a valid and specified system of comparison. To calibrate well-logging tools, sensing systems are designed which produce consistent and repeatable indications over the range for which the tool was intended. The basics of calibration theory, procedures, and calibration record presentations are reviewed. Calibrations for induction, electrical, radioactivity, and sonic logging tools will be discussed. The authors' intent is to provide an understanding of the sources of errors, of the way errors are minimized in the calibration process, and of the significance of changes in recorded calibration data

  18. Logging Concessions Enable Illegal Logging Crisis in the Peruvian Amazon

    OpenAIRE

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

    2014-01-01

    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%...

  19. Log of Apollo 11.

    Science.gov (United States)

    National Aeronautics and Space Administration, Washington, DC.

    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)

  20. Borehole logging system

    International Nuclear Information System (INIS)

    Allen, L.S.

    1988-01-01

    A radioactive borehole logging tool employs an epithermal neutron detector having a neutron counter surrounded by an inner thermal neutron filter and an outer thermal neutron filter. Located between the inner and outer filters is a neutron moderating material for extending the lifetime of epithermal neutrons to enhance the counting rate of such epithermal neutrons by the neutron counter

  1. CMLOG: A common message logging system

    International Nuclear Information System (INIS)

    Chen, J.; Akers, W.; Bickley, M.; Wu, D.; Watson, W. III

    1997-01-01

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

  2. IMPROVED log(gf ) VALUES OF SELECTED LINES IN Mn I AND Mn II FOR ABUNDANCE DETERMINATIONS IN FGK DWARFS AND GIANTS

    International Nuclear Information System (INIS)

    Den Hartog, E. A.; Lawler, J. E.; Sobeck, J. S.; Sneden, C.; Cowan, J. J.

    2011-01-01

    The goal of the present work is to produce transition probabilities with very low uncertainties for a selected set of multiplets of Mn I and Mn II. Multiplets are chosen based upon their suitability for stellar abundance analysis. We report on new radiative lifetime measurements for 22 levels of Mn I from the e 8 D, z 6 P, z 6 D, z 4 F, e 8 S, and e 6 S terms and six levels of Mn II from the z 5 P and z 7 P terms using time-resolved laser-induced fluorescence on a slow atom/ion beam. New branching fractions for transitions from these levels, measured using a Fourier-transform spectrometer, are reported. When combined, these measurements yield transition probabilities for 47 transitions of Mn I and 15 transitions of Mn II. Comparisons are made to data from the literature and to Russell-Saunders (LS) theory. In keeping with the goal of producing a set of transition probabilities with the highest possible accuracy and precision, we recommend a weighted mean result incorporating our measurements on Mn I and II as well as independent measurements or calculations that we view as reliable and of a quality similar to ours. In a forthcoming paper, these Mn I/II transition probability data will be utilized to derive the Mn abundance in stars with spectra from both space-based and ground-based facilities over a 4000 A wavelength range. With the employment of a local thermodynamic equilibrium line transfer code, the Mn I/II ionization balance will be determined for stars of different evolutionary states.

  3. Neutron--neutron logging

    International Nuclear Information System (INIS)

    Allen, L.S.

    1977-01-01

    A borehole logging tool includes a steady-state source of fast neutrons, two epithermal neutron detectors, and two thermal neutron detectors. A count rate meter is connected to each neutron detector. A first ratio detector provides an indication of the porosity of the formation surrounding the borehole by determining the ratio of the outputs of the two count rate meters connected to the two epithermal neutron detectors. A second ratio detector provides an indication of both porosity and macroscopic absorption cross section of the formation surrounding the borehole by determining the ratio of the outputs of the two count rate meters connected to the two thermal neutron detectors. By comparing the signals of the two ratio detectors, oil bearing zones and salt water bearing zones within the formation being logged can be distinguished and the amount of oil saturation can be determined. 6 claims, 2 figures

  4. Geophysical borehole logging

    International Nuclear Information System (INIS)

    McCann, D.; Barton, K.J.; Hearn, K.

    1981-08-01

    Most of the available literature on geophysical borehole logging refers to studies carried out in sedimentary rocks. It is only in recent years that any great interest has been shown in geophysical logging in boreholes in metamorphic and igneous rocks following the development of research programmes associated with geothermal energy and nuclear waste disposal. This report is concerned with the programme of geophysical logging carried out on the three deep boreholes at Altnabreac, Caithness, to examine the effectiveness of these methods in crystalline rock. Of particular importance is the assessment of the performance of the various geophysical sondes run in the boreholes in relation to the rock mass properties. The geophysical data can be used to provide additional in-situ information on the geological, hydrogeological and engineering properties of the rock mass. Fracturing and weathering in the rock mass have a considerable effect on both the design parameters for an engineering structure and the flow of water through the rock mass; hence, the relation between the geophysical properties and the degree of fracturing and weathering is examined in some detail. (author)

  5. Well logging with natural gamma radiation

    International Nuclear Information System (INIS)

    Ellis, D.V.

    1983-01-01

    An invention is described for use in natural gamma radiation well logging in which measurements taken in a borehole are used in the search for valuable underground resources such as oil or gas. The invention comprises deriving a log of natural gamma radiation detected in selected energy windows for a selected borehole depth interval and converting it into a log of the selected subsurface materials, e.g. Th, U, K. This log is corrected for the effects of 1) either a gamma ray emitter in the borehole fluid, e.g. potassium salts and/or 2) a gamma ray attenuator in the borehole fluid, e.g. a strong attenuator such as barite and/or hematite. The Th, U, K log is particularly useful in the exploration of oil and gas resources since the Th, U, K concentrations are a good indication as to the presence, type and volume of shale and clay in the formations surrounding the borehole. (U.K.)

  6. Modelling tropical forests response to logging

    Science.gov (United States)

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

    2013-04-01

    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.

  7. Pulse neutron logging technique

    International Nuclear Information System (INIS)

    Bespalov, D.F.; Dylyuk, A.A.

    1975-01-01

    A new method of neutron-burst logging is proposed, residing in irradiating rocks with fast neutron bursts and registering the integrated flux burst of thermal and/or epithermal neutrons, from the moment of its initiation to that of full absorption. The obtaained value is representative of the rock properties (porosity, hydrogen content). The integrated flux in a burst of thermal and epithermal neutrons can be measured both by way of activation of a reference sample of a known chemical composition during the neutron burst and by recording the radiation of induced activity of the sample within an interval between two bursts. The proposed method features high informative value, accuracy and efficiency

  8. Soil water storage in an upland forest after selective logging in Central Amazonia Armazenamento de água no solo após extração seletiva de madeira em floresta de terra firme na Amazônia Central

    Directory of Open Access Journals (Sweden)

    S. J. F. Ferreira

    2004-02-01

    Full Text Available Soil water storage of Central Amazonian soil profiles in upland forest plots subjected to selective logging (in average, 8 trees or 34, 3 m³ of timber per hectare were removed was measured in four layers, down to a depth of 70 cm. The study lasted 27-months and was divided in two phases: measurements were carried out nearly every week during the first 15 months; in the following year, five intensive periods of measurements were performed. Five damage levels were compared: (a control (undisturbed forest plot; (b centre of the clearing/gap; (c edge of the gap; (d edge of the remaining forest; and (e remaining forest. The lowest values for water storage were found in the control (296 ± 19.1 mm, while the highest were observed (333 ± 25.8 mm in the centre of the gap, during the dry period. In the older gaps (7.5-8.5 year old, soil water storage was similar to the remaining and the control forest, indicating a recovery of hydric soil properties to nearly the levels prior to selective logging.Foi medido o armazenamento de água em perfis de solo de 0-70 cm, divididos em quatro camadas em parcelas de floresta de terra firme na Amazônia Central, submetidas à extração seletiva de madeira, tendo sido retiradas, em média, 8 árvores por hectare ou 34 m³ de madeira. O estudo foi realizado num período de 27 meses em duas fases: na primeira, as medidas foram, na sua maioria, semanais, num período de 15 meses. Na segunda, as medidas foram feitas em cinco períodos intensivos. Foram comparados cinco tratamentos: (a controle (floresta intacta, (b centro da clareira, (c borda da clareira, (d borda da floresta remanescente e (e floresta remanescente. Os valores mais baixos de armazenamento de água no solo (296 ± 19,1 mm foram encontrados no controle, enquanto os mais altos foram medidos no centro da clareira (333 ± 25,8 mm, no período seco. Nas clareiras mais antigas (7,5-8,5 anos de idade, os armazenamentos de água no solo foram similares aos da

  9. Nova Event Logging System

    International Nuclear Information System (INIS)

    Calliger, R.J.; Suski, G.J.

    1981-01-01

    Nova is a 200 terawatt, 10-beam High Energy Glass Laser currently under construction at LLNL. This facility, designed to demonstrate the feasibility of laser driven inertial confinement fusion, contains over 5000 elements requiring coordinated control, data acquisition, and analysis functions. The large amounts of data that will be generated must be maintained over the life of the facility. Often the most useful but inaccessible data is that related to time dependent events associated with, for example, operator actions or experiment activity. We have developed an Event Logging System to synchronously record, maintain, and analyze, in part, this data. We see the system as being particularly useful to the physics and engineering staffs of medium and large facilities in that it is entirely separate from experimental apparatus and control devices. The design criteria, implementation, use, and benefits of such a system will be discussed

  10. Querying Workflow Logs

    Directory of Open Access Journals (Sweden)

    Yan Tang

    2018-01-01

    Full Text Available A business process or workflow is an assembly of tasks that accomplishes a business goal. Business process management is the study of the design, configuration/implementation, enactment and monitoring, analysis, and re-design of workflows. The traditional methodology for the re-design and improvement of workflows relies on the well-known sequence of extract, transform, and load (ETL, data/process warehousing, and online analytical processing (OLAP tools. In this paper, we study the ad hoc queryiny of process enactments for (data-centric business processes, bypassing the traditional methodology for more flexibility in querying. We develop an algebraic query language based on “incident patterns” with four operators inspired from Business Process Model and Notation (BPMN representation, allowing the user to formulate ad hoc queries directly over workflow logs. A formal semantics of this query language, a preliminary query evaluation algorithm, and a group of elementary properties of the operators are provided.

  11. Interpretation of horizontal well production logs: influence of logging tool

    Energy Technology Data Exchange (ETDEWEB)

    Ozkan, E. [Colorado School of Mines, Boulder, CO (United States); Sarica, C. [Pennsylvania State Univ., College Park, PA (United States); Haci, M. [Drilling Measurements, Inc (United States)

    1998-12-31

    The influence of a production-logging tool on wellbore flow rate and pressure measurements was investigated, focusing on the disturbence caused by the production-logging tool and the coiled tubing on the original flow conditions in the wellbore. The investigation was carried out using an analytical model and single-phase liquid flow was assumed. Results showed that the production-logging tool influenced the measurements as shown by the deviation of the original flow-rate, pressure profiles and low-conductivity wellbores. High production rates increase the effect of the production-logging tool. Recovering or inferring the original flow conditions in the wellbore from the production-logging data is a very complex process which cannot be solved easily. For this reason, the conditions under which the information obtained by production-logging is meaningful is of considerable practical interest. 7 refs., 2 tabs., 15 figs.

  12. Fermat's Last Theorem A Theorem at Last!

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 1. Fermat's Last Theorem A Theorem at Last! C S Yogananda. General Article Volume 1 Issue 1 January 1996 pp 71-79. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/001/01/0071-0079 ...

  13. Logging a roadside stand to protect scenic values

    Science.gov (United States)

    Philip M. McDonald; Raymond V. Whiteley

    1972-01-01

    A case study on the Challenge Experimental Forest, California, demonstrated that logging along roadsides need not despoil roadside stands. Nearly every tree was "viewed" before marking. Because of the "special-care" procedures followed, combined logging and slash-disposal cost was about twice that of a single-tree selection cut.

  14. Veneer-log production and receipts, North Central Region, 1976.

    Science.gov (United States)

    James E. Blyth; Jerold T. Hahn

    1978-01-01

    Shows 1976 veneer-log production and receipts by species in the Lake States (Michigan, Minnesota, and Wisconsin) and in the Central States (Illinois, Indiana, Iowa, and Missouri). Comparisons are made with similar data for 1974. Includes tables showing veneer-log production and receipts (for selected years) since 1946 in the Lake States and since 1956 in the Central...

  15. Veneer-log production and receipts, North Central Region, 1974.

    Science.gov (United States)

    James E. Blyth; Jerold T. Hahn

    1976-01-01

    Shows 1974 veneer-log production and receipts by species in the Lake States (Michigan, Minnesota, and Wisconsin) and in the Central States (Illinois, Indiana, Iowa, and Missouri). Comparisons are made with similar data for 1972. Includes tables showing veneer-log production and receipts (for selected years) since 1946 in the Lake States and since 1956 in the Central...

  16. Fates of trees damaged by logging in Amazonian Bolivia

    NARCIS (Netherlands)

    Shenkin, A.; Bolker, B.; Peña Claros, M.; Licona, J.C.; Putz, F.E.

    2015-01-01

    Estimation of carbon losses from trees felled and incidentally-killed during selective logging of tropical forests is relatively straightforward and well-documented, but less is known about the fates of collaterally-damaged trees that initially survive. Tree response to logging damage is an

  17. ADN* Density log estimation Using Rockcell*

    International Nuclear Information System (INIS)

    Okuku, C.; Iloghalu, Emeka. M.; Omotayo, O.

    2003-01-01

    This work is intended to inform on the possibilities of estimating good density data in zones associated with sliding in a reservoir with ADN* tool with or without ADOS in string in cases where repeat sections were not done, possibly due to hole stability or directional concerns. This procedure has been equally used to obtain a better density data in corkscrew holes. Density data (ROBB) was recomputed using neural network in RockCell* to estimate the density over zones of interest. RockCell* is a Schlumberger software that has neural network functionally which can be used to estimate missing logs using the combination of the responses of other log curves and intervals that are not affected by sliding. In this work, an interval was selected and within this interval twelve litho zones were defined using the unsupervised neural network. From this a training set was selected based on intervals of very good log responses outside the sliding zones. This training set was used to train and run the neural network for a specific lithostratigraphic interval. The results matched the known good density curve. Then after this, an estimation of the density curve was done using the supervised neural network. The output from this estimation matched very closely in the good portions of the log, thus providing some density measurements in the sliding zone. This methodology provides a scientific solution to missing data during the process of Formation evaluation

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

    International Nuclear Information System (INIS)

    Schimschal, U.; Nelson, P.H.

    1991-01-01

    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. The authors 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

  19. Results of mine logging in Sn-W prospectina in Cinovec deposit

    International Nuclear Information System (INIS)

    Kudrna, R.; Masek, K.; Pavlik, I.; Rejl, L.

    1984-01-01

    The method is suggested of indicating cassiterite ore mineralization in the Cinovec deposit by combining the methods of selective gamma-gamma logging and magnetic susceptibility logging. The estimate of the tin content was based on selective gamma-gamma logging. (B.S.)

  20. Logging Concessions Enable Illegal Logging Crisis in the Peruvian Amazon

    Science.gov (United States)

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

    2014-04-01

    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.

  1. Logging concessions enable illegal logging crisis in the Peruvian Amazon.

    Science.gov (United States)

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

    2014-04-17

    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.

  2. Methods for processing of pulsed neutron logging data

    International Nuclear Information System (INIS)

    Iskenderov, V.G.

    1975-01-01

    Conditions were examined for calculating the lifetime of thermal neutrons in neutron-neutron logging by selecting optimum values for the time lag. The dispersion and mean square error of the calculated lifetime values for thermal neutrons are evaluated

  3. A Generic Current Mode Design for Multifunction Grounded Capacitor Filters Employing Log-Domain Technique

    Directory of Open Access Journals (Sweden)

    N. A. Shah

    2011-01-01

    Full Text Available A generic design (GD for realizing an nth order log-domain multifunction filter (MFF, which can yield four possible stable filter configurations, each offering simultaneously lowpass (LP, highpass (HP, and bandpass (BP frequency responses, is presented. The features of these filters are very simple, consisting of merely a few exponential transconductor cells and capacitors; all grounded elements, capable of absorbing the shunt parasitic capacitances, responses are electronically tuneable, and suitable for monolithic integration. Furthermore, being designed using log-domain technique, it offers all its advantages. As an example, 5th-order MFFs are designed in each case and their performances are evaluated through simulation. Lastly, a comparative study of the MFFs is also carried, which helps in selecting better high-order MFF for a given application.

  4. SNG-logs at Skjern

    DEFF Research Database (Denmark)

    Korsbech, Uffe C C; Petersen, Jesper; Aage, Helle Karina

    1998-01-01

    Spectral Natural Gamma-ray logs have been run in two water supply borings at Skjern. The log data have been examined by a new technique - Noise Adjusted Singular Value Decomposition - in order to get a detailed and reliable picture of the distribution of uranium and thorium gamma-rays from heavy...

  5. Geomicrobial Optical Logging Detectors (GOLD)

    Science.gov (United States)

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

    2008-12-01

    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 core analyses, especially where instances of missing or damaged core sections make such studies difficult. Incorporated into these instruments will be a sampling/inoculation tool to allow for the recovery and/or manipulation of particularly interesting sections of the borehole wall for further study, enabling a series of microbiological studies. The borehole tools we will develop revolve around key emerging technologies and methods, some of which are briefly described below: 1) Autofluorescence Spectroscopy: Building on past instruments, we will develop a new borehole logger that searches for microbial life and organics using fluorescence spectroscopy. Many important organic compounds (e.g. PAHs) and biomolecules (e.g. aromatic amino acids, proteins, methanogenic coenzymes) fluoresce when excited with ultraviolet and visible light. Through the careful selection of excitation wavelength(s) and temporal gating parameters, a borehole logging instrument can detect and differentiate between these different compounds and the mineral matrix in which they exist. 2) Raman Spectroscopy: Though less sensitive than fluorescence spectroscopy, Raman spectroscopy is more definitive: it can provide important mineral phase distribution/proportions and other chemical data enabling studies of mineralogy and microbe-mineral interactions (when combined with fluorescence). 3) Borehole Camera: Imaging of the borehole wall with extended information in the UV, visible, and NIR for a more informative view can provide a lot of insight

  6. Engineering aspects of radiometric logging

    International Nuclear Information System (INIS)

    Huppert, P.

    1982-01-01

    Engineering problems encountered in the development of nuclear borehole logging techniques are discussed. Spectrometric techniques require electronic stability of the equipment. In addition the electronics must be capable of handling high count rates of randomly distributed pulses of fast rise time from the detector and the systems must be designed so that precise calibration is possible under field operating conditions. Components of a logging system are discussed in detail. They include the logging probe (electronics, detector, high voltage supply, preamplifier), electronic instrumentation for data collection and processing and auxiliary equipment

  7. Log-balanced combinatorial sequences

    Directory of Open Access Journals (Sweden)

    Tomislav Došlic

    2005-01-01

    Full Text Available We consider log-convex sequences that satisfy an additional constraint imposed on their rate of growth. We call such sequences log-balanced. It is shown that all such sequences satisfy a pair of double inequalities. Sufficient conditions for log-balancedness are given for the case when the sequence satisfies a two- (or more- term linear recurrence. It is shown that many combinatorially interesting sequences belong to this class, and, as a consequence, that the above-mentioned double inequalities are valid for all of them.

  8. Projeção da distribuição diamétrica de uma floresta explorada seletivamente na Amazônia Ocidental Projection of the diameter distribution in a selective logging forest in the western Amazon

    Directory of Open Access Journals (Sweden)

    Sumaia S. Vasconcelos

    2009-03-01

    Full Text Available Utilizando um modelo estocástico, foi projetada a distribuição diamétrica futura de uma floresta submetida à exploração seletiva de madeira na Amazônia Ocidental. Foram utilizados dados de cinco parcelas permanentes localizadas no PC Pedro Peixoto, no Acre. A primeira medição das parcelas ocorreu em 1996, a exploração florestal em 1997 e as re-medições em 1999 e 2001. A principal variável utilizada foi o diâmetro à altura do peito (DAP. A matriz de transição probabilística (Cadeia de Markov foi utilizada para fazer a projeção da distribuição diamétrica do número de árvores sobreviventes nas classes diamétricas. O modelo foi primeiramente testado para fazer a projeção para 2001, tendo como base as observações de 1999 e seu passado imediato (1997. Quando comparadas às projeções feitas para 2001 e as medições de campo (2001, o teste Qui-quadrado mostrou que não houve diferença significativa entre freqüências esperadas e observadas na distribuição diamétrica (p=0,05. A projeção para 2005 indica que a taxa de mortalidade será próxima a de 2001, e se repetida a taxa de recrutamento em 2005 o total de árvores será maior que o observado em 2001. Esse comportamento da floresta indica que não existe um padrão definido para a dinâmica nas classes diamétricas em termos de mortalidade ou crescimento, apresentando um comportamento aleatório ou probabilístico, justificando a eficiência da Cadeia de Markov para projetar a dinâmica da floresta estudada, podendo auxiliar na determinação do ciclo de corte ou mostrando as tendências que a floresta de hoje apresentará em um futuro próximo.The diameter distribution of an experimental forest stand in the Western Amazon was projected using a stochastic model after selective logging. The study was developed using data from five permanent plots located in the colonization project Pedro Peixoto, in the state of Acre. Initial measurements of diameter at breast

  9. VT Route Log Points 2017

    Data.gov (United States)

    Vermont Center for Geographic Information — This data layer is used with VTrans' Integrated Route Log System (IRA). It is also used to calibrate the linear referencing systems, including the End-to-End and...

  10. New materials for fireplace logs

    Science.gov (United States)

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

    1971-01-01

    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.

  11. Palm distributions for log Gaussian Cox processes

    DEFF Research Database (Denmark)

    Coeurjolly, Jean-Francois; Møller, Jesper; Waagepetersen, Rasmus Plenge

    2017-01-01

    This paper establishes a remarkable result regarding Palm distributions for a log Gaussian Cox process: the reduced Palm distribution for a log Gaussian Cox process is itself a log Gaussian Cox process that only differs from the original log Gaussian Cox process in the intensity function. This new...... result is used to study functional summaries for log Gaussian Cox processes....

  12. Log quality enhancement: A systematic assessment of logging company wellsite performance and log quality

    International Nuclear Information System (INIS)

    Farnan, R.A.; Mc Hattie, C.M.

    1984-01-01

    To improve the monitoring of logging company performance, computer programs were developed to assess information en masse from log quality check lists completed on wellsite by the service company engineer and Phillips representative. A study of all logging jobs performed by different service companies for Phillips in Oklahoma (panhandle excepted) during 1982 enabled several pertinent and beneficial interpretations to be made. Company A provided the best tool and crew service. Company B incurred an excessive amount of lost time related to tool failure, in particular the neutron-density tool combination. Company C, although used only three times, incurred no lost time. With a reasonable data base valid conclusions were made pertaining, for example, to repeated tool malfunctions. The actual logs were then assessed for quality

  13. Pulsed neutron generator for logging

    International Nuclear Information System (INIS)

    Thibideau, F.D.

    1977-01-01

    A pulsed neutron generator for uranium logging is described. This generator is one component of a prototype uranium logging probe which is being developed by SLA to detect, and assay, uranium by borehole logging. The logging method is based on the measurement of epithermal neutrons resulting from the prompt fissioning of uranium from a pulsed source of 17.6 MeV neutrons. An objective of the prototype probe was that its diameter not exceed 2.75 inches, which would allow its use in conventional rotary drill holes of 4.75-inch diameter. This restriction limited the generator to a maximum 2.375-inch diameter. The performance requirements for the neutron generator specified that it operate with a nominal output of 5 x 10 6 neutrons/pulse at up to 100 pulses/second for a one-hour period. The development of a neutron generator meeting the preliminary design goals was completed and two prototype models were delivered to SLA. These two generators have been used by SLA to log a number of boreholes in field evaluation of the probe. The results of the field evaluations have led to the recommendation of several changes to improve the probe's operation. Some of these changes will require additional development effort on the neutron generator. It is expected that this work will be performed during 1977. The design and operation of the first prototype neutron generators is described

  14. The log S -log N distribution of gamma ray brust

    International Nuclear Information System (INIS)

    Yamagami, Takamasa; Nishimura, Jun; Fujii, Masami

    1982-01-01

    The relation between the size S and the frequency N of gamma ray burst has been studied. This relation may be determined from the celestial distribution of gamma ray burst sources. The present analysis gives that the log S - log N relation for any direction is determined by the celestial distribution of gamma ray burst sources. The observed bursts were analyzed. The celestial distribution of gamma ray burst sources was observed by the satellites of USSR. The results showed that the distribution seemed to be isotropic. However, the calculated log S - log N relation based on the isotropic distribution wasF in disagreement with the observed ones. As the result of analysis, it was found that the observed bursts missed low energy part because of the threshold of detectors. The levels of discrimination of detection were not clear. When a proper threshold level is set for each type of burst, and the size of bursts is determined, the above mentioned discrepancy will be deleted regardless of luminosity and the spatial distribution of bursts. (Kato, T.)

  15. Mud Logging; Control geologico en perforaciones petroliferas (Mud Logging)

    Energy Technology Data Exchange (ETDEWEB)

    Pumarega Lafuente, J.C.

    1994-12-31

    Mud Logging is an important activity in the oil field and it is a key job in drilling operations, our duties are the acquisition, collection and interpretation of the geological and engineering data at the wellsite, also inform the client immediately of any significant changes in the well. (Author)

  16. Borehole logging for uranium exploration

    International Nuclear Information System (INIS)

    1982-01-01

    The present text has been prepared taking into account the requirements of both developing countries, which might be at an incipient stage of uranium exploration, and industrialized countries, where more advanced exploration and resource evaluation techniques are commonly in use. While it was felt necessary to include some discussion of exploration concepts and fundamental physical principles underlying various logging methods, it was not the intention of the consultants to provide a thorough, detailed explanation of the various techniques, or even to give a comprehensive listing thereof. However, a list of references has been included, and it is strongly recommended that the serious student of mineral logging consult this list for further guidance

  17. Pulsed neutron porosity logging system

    International Nuclear Information System (INIS)

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

    1978-01-01

    An improved pulsed neutron porosity logging system is provided in the present invention. A logging tool provided with a 14 MeV pulsed neutron source, an epithermal neutron detector, and a fast neutron detector is moved through a borehole. Repetitive bursts of neutrons irradiate the earth formations and, during the bursts, the fast neutron population is sampled. During the interval between bursts the epithermal neutron population is sampled along with background gamma radiation due to lingering thermal neutrons. The fast and epithermal neutron population measurements are combined to provide a measurement of formation porosity

  18. On conditional independence and log-convexity

    Czech Academy of Sciences Publication Activity Database

    Matúš, František

    2012-01-01

    Roč. 48, č. 4 (2012), s. 1137-1147 ISSN 0246-0203 R&D Projects: GA AV ČR IAA100750603; GA ČR GA201/08/0539 Institutional support: RVO:67985556 Keywords : Conditional independence * Markov properties * factorizable distributions * graphical Markov models * log-convexity * Gibbs- Markov equivalence * Markov fields * Gaussian distributions * positive definite matrices * covariance selection model Subject RIV: BA - General Mathematics Impact factor: 0.933, year: 2012 http://library.utia.cas.cz/separaty/2013/MTR/matus-0386229.pdf

  19. Eesti laste suvi

    Index Scriptorium Estoniae

    2010-01-01

    Laste suvisest koolivaheajast räägivad Eesti omavalitsuse ametnikud ja sotsiaaltöötajad: Kaasi Almers, Inna Kask, Aasa Saarna, Ülle Rajasalu, Merle Leopard, Aime Koger, Margit Pajo, Pilleriin Aalde, Andres Julle ja Tiiu Kuus

  20. Logging Work Injuries in Appalachia

    Science.gov (United States)

    Charles H. Wolf; Gilbert P. Dempsey

    1978-01-01

    Logging accidents are costly. They may bring pain to injured workers, hardship to their families, and higher insurance premiums and lower productivity to their employers. Our analysis of 1,172 injuries in central Appalachia reveals that nearly half of all time lost-and almost all fatalities-resulted from accidents during felling and unloading. The largest proportion of...

  1. Get better cased well data with the carbon/oxygen log

    International Nuclear Information System (INIS)

    Fertl, W.H.; Frost, E.

    1982-01-01

    Using case studies from heavy oil environments in the U.S. and Canada, it is shown how the continuous carbon/oxygen log, a type of pulsed neutron log, has proven an effective cased-hole reservoir evaluation and monitoring device. The article is a follow-up to one last month that detailed how the C/O log operates and reviewed case studies of its use in sandstone and carbonate environments

  2. Hardwood log supply: a broader perspective

    Science.gov (United States)

    Iris Montague; Adri Andersch; Jan Wiedenbeck; Urs. Buehlmann

    2015-01-01

    At regional and state meetings we talk with others in our business about the problems we face: log exports, log quality, log markets, logger shortages, cash flow problems, the weather. These are familiar talking points and real and persistent problems. But what is the relative importance of these problems for log procurement in different regions of...

  3. Unsupervised signature extraction from forensic logs

    NARCIS (Netherlands)

    Thaler, S.M.; Menkovski, V.; Petkovic, M.; Altun, Y.; Das, K.; Mielikäinen, T.; Malerba, D.; Stefanowski, J.; Read, J.; Žitnik, M.; Ceci, M.

    2017-01-01

    Signature extraction is a key part of forensic log analysis. It involves recognizing patterns in log lines such that log lines that originated from the same line of code are grouped together. A log signature consists of immutable parts and mutable parts. The immutable parts define the signature, and

  4. A method of estimating log weights.

    Science.gov (United States)

    Charles N. Mann; Hilton H. Lysons

    1972-01-01

    This paper presents a practical method of estimating the weights of logs before they are yarded. Knowledge of log weights is required to achieve optimum loading of modern yarding equipment. Truckloads of logs are weighed and measured to obtain a local density index (pounds per cubic foot) for a species of logs. The density index is then used to estimate the weights of...

  5. Nondestructive evaluation for sorting red maple logs

    Science.gov (United States)

    Xiping Wang; Robert J. Ross; David W. Green; Karl Englund; Michael Wolcott

    2000-01-01

    Existing log grading procedures in the United States make only visual assessments of log quality. These procedures do not incorporate estimates of the modulus of elasticity (MOE) of logs. It is questionable whether the visual grading procedures currently used for logs adequately assess the potential quality of structural products manufactured from them, especially...

  6. The last interglacial climate

    DEFF Research Database (Denmark)

    Pedersen, Rasmus A.; Langen, Peter L.; Vinther, Bo M.

    2017-01-01

    The last interglacial climate was influenced by substantial changes in the annual insolation cycle that led to a warmer climate state with pronounced high northern latitude warming. We analyze the impact of the insolation changes 125,000 years before present using an equilibrium snapshot simulation...... with the EC-Earth coupled climate model at high spatial resolution. Using additional atmosphere-only simulations, we separate the direct impact from the changed insolation from the secondary contribution from changed sea surface conditions. These simulations are forced with a combination of last interglacial...

  7. Uranium logging in earth formations

    International Nuclear Information System (INIS)

    Givens, W.W.

    1979-01-01

    A technique is provided for assaying the formations surrounding a borehole for uranium. A borehole logging tool cyclically irradiates the formations with neutrons and responds to neutron fluxes produced during the period of time that prompt neutrons are being produced by the neutron fission of uranium in the formations. A borehole calibration tool employs a steady-state (continuous output) neutron source, firstly, to produce a response to neutron fluxes in models having known concentrations of uranium and, secondly, to to produce a response to neutron fluxes in the formations surrounding the borehole. The neutron flux responses of the borehole calibration tool in both the model and the formations surrounding the borehole are utilized to correct the neutron flux response of the borehole logging tool for the effects of epithermal/thermal neutron moderation, scattering, and absorption within the borehole itself

  8. Logística empresarial

    OpenAIRE

    Feres Sahid

    1987-01-01

    RESUMEN El concepto logístico, se pudo ver reflejado con exactitud desde el punto de vista etimológico e histórico a través de la revista de la E.A.N; ya que  tiene cierto carácter militar que lo hace característico a la gestión empresarial y de esto se formula un debate definitivo de este concepto.

  9. Chemical logging of geothermal wells

    Science.gov (United States)

    Allen, C.A.; McAtee, R.E.

    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.

  10. Audit Log for Forensic Photography

    Science.gov (United States)

    Neville, Timothy; Sorell, Matthew

    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.

  11. Logística empresarial

    Directory of Open Access Journals (Sweden)

    Feres Sahid

    1987-04-01

    Full Text Available RESUMEN El concepto logístico, se pudo ver reflejado con exactitud desde el punto de vista etimológico e histórico a través de la revista de la E.A.N; ya que  tiene cierto carácter militar que lo hace característico a la gestión empresarial y de esto se formula un debate definitivo de este concepto.

  12. Neutron capture in borehole logging

    International Nuclear Information System (INIS)

    Randall, R.R.

    1981-01-01

    The use is described of a pulsed source of fast neutrons and a radiation detector to measure the thermal neutron population decay rate in a well logging instrument. The macroscopic neutron absorption cross-section is calculated by taking the natural logarithm of the ratio of the detected radiation counts occurring within two measurement intervals of fixed duration and starting at a fixed time after a neutron burst. (U.K.)

  13. Borehole logging in uranium exploration

    International Nuclear Information System (INIS)

    Kulkarni, N.H.

    1992-01-01

    The ultimate objective of exploration by drilling as far as Atomic Minerals Division is concerned is to locate the ore zone in the subsurface, draw samples and analyze them for their metal content. The presence of the ore zone is also indicated by gamma-ray logging of the borehole. A gamma-ray detector is lowered in the borehole and precise depth and grade of the ore zone is established. This helps the geologist in correlating the ore horizon with the surface outcrop or the ore zone intercepted in adjoining boreholes and in deciding about further drilling and location of boreholes. Most commonly, total gamma measurements are made although some units capable of measuring the gamma-ray spectrum are also in use. It is possible to know if the mineralization is due to uranium without waiting for the laboratory results. The present write up gives a brief account of the principles, equipment and methods of borehole gamma-ray logging including density and self-potential logging. (author). 8 refs., 5 figs

  14. Dynamic Planar Convex Hull with Optimal Query Time and O(log n · log log n ) Update Time

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Jakob, Riko

    2000-01-01

    The dynamic maintenance of the convex hull of a set of points in the plane is one of the most important problems in computational geometry. We present a data structure supporting point insertions in amortized O(log n · log log log n) time, point deletions in amortized O(log n · log log n) time......, and various queries about the convex hull in optimal O(log n) worst-case time. The data structure requires O(n) space. Applications of the new dynamic convex hull data structure are improved deterministic algorithms for the k-level problem and the red-blue segment intersection problem where all red and all...

  15. The Last Big Bang

    Energy Technology Data Exchange (ETDEWEB)

    McGuire, Austin D. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Meade, Roger Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-13

    As one of the very few people in the world to give the “go/no go” decision to detonate a nuclear device, Austin “Mac” McGuire holds a very special place in the history of both the Los Alamos National Laboratory and the world. As Commander of Joint Task Force Unit 8.1.1, on Christmas Island in the spring and summer of 1962, Mac directed the Los Alamos data collection efforts for twelve of the last atmospheric nuclear detonations conducted by the United States. Since data collection was at the heart of nuclear weapon testing, it fell to Mac to make the ultimate decision to detonate each test device. He calls his experience THE LAST BIG BANG, since these tests, part of Operation Dominic, were characterized by the dramatic displays of the heat, light, and sounds unique to atmospheric nuclear detonations – never, perhaps, to be witnessed again.

  16. Connecting the last billion

    OpenAIRE

    Ben David, Yahel

    2015-01-01

    The last billion people to join the online world, are likely to face at least one of two obstacles:Part I: Rural Internet AccessRural, sparsely populated, areas make conventional infrastructure investments unfeasible: Bigcorporations attempt to address this challenge via the launch of Low-Earth-Orbiting (LEO) satelliteconstellations, fleets of high-altitude balloons, and giant solar-powered drones; although thesegrandiose initiatives hold potential, they are costly and risky. At the same time...

  17. The last SPR dinner awards

    Science.gov (United States)

    Tsurutani, Bruce

    1992-03-01

    Because the Solar-Planetary Relationships section of AGU has officially changed its name to Space Physics and Aeronomy (SPA), the December 10, 1991, section dinner award ceremony at the AGU Fall Meeting in San Francisco was the last of the series. Presumably an SPA dinner award series will be started under President-elect Andy Nagy.We have followed our tradition of recognizing the special talents of section members at the annual dinner. This year we had eight awardees. These awards are given in fun and are intended to be humorous. The selection committee defining the awards (the awards are changed regularly to keep people from trying to win one) and selecting the awardees will have to remain anonymous. (The committee is similar to Skull and Bones, but we are politically correct in that we allow women as members.)

  18. Data Mining of Network Logs

    Science.gov (United States)

    Collazo, Carlimar

    2011-01-01

    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.

  19. Neutron borehole logging correction technique

    International Nuclear Information System (INIS)

    Goldman, L.H.

    1978-01-01

    In accordance with an illustrative embodiment of the present invention, a method and apparatus is disclosed for logging earth formations traversed by a borehole in which an earth formation is irradiated with neutrons and gamma radiation produced thereby in the formation and in the borehole is detected. A sleeve or shield for capturing neutrons from the borehole and producing gamma radiation characteristic of that capture is provided to give an indication of the contribution of borehole capture events to the total detected gamma radiation. It is then possible to correct from those borehole effects the total detected gamma radiation and any earth formation parameters determined therefrom

  20. Benchmark neutron porosity log calculations

    International Nuclear Information System (INIS)

    Little, R.C.; Michael, M.; Verghese, K.; Gardner, R.P.

    1989-01-01

    Calculations have been made for a benchmark neutron porosity log problem with the general purpose Monte Carlo code MCNP and the specific purpose Monte Carlo code McDNL. For accuracy and timing comparison purposes the CRAY XMP and MicroVax II computers have been used with these codes. The CRAY has been used for an analog version of the MCNP code while the MicroVax II has been used for the optimized variance reduction versions of both codes. Results indicate that the two codes give the same results within calculated standard deviations. Comparisons are given and discussed for accuracy (precision) and computation times for the two codes

  1. 29 CFR 1918.88 - Log operations.

    Science.gov (United States)

    2010-07-01

    ...) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Handling Cargo § 1918.88 Log operations. (a) Working in..., the employer shall ensure that employees remain clear of areas where logs being dumped could strike...

  2. Artificial intelligence approach to interwell log correlation

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jong-Se [Korea Maritime University, Pusan(Korea); Kang, Joo Myung [Seoul National University, Seoul(Korea); Kim, Jung Whan [Korea National Oil Corp., Anyang(Korea)

    2000-04-30

    This paper describes a new approach to automated interwell log correlation using artificial intelligence and principal component analysis. The approach to correlate wire line logging data is on the basis of a large set of subjective rules that are intended to represent human logical processes. The data processed are mainly the qualitative information such as the characteristics of the shapes extracted along log traces. The apparent geologic zones are identified by pattern recognition for the specific characteristics of log trace collected as a set of objects by object oriented programming. The correlation of zones between wells is made by rule-based inference program. The reliable correlation can be established from the first principal component logs derived from both the important information around well bore and the largest common part of variances of all available well log data. Correlation with field log data shows that this approach can make interwell log correlation more reliable and accurate. (author). 6 refs., 7 figs.

  3. Face logging in Copenhagen Limestone, Denmark

    DEFF Research Database (Denmark)

    Jakobsen, Lisa; Foged, Niels Nielsen; Erichsen, Lars

    2015-01-01

    tunnel in Copenhagen more than 2.5 km face logs were made in 467 locations at underground stations, shafts, caverns and along bored tunnels. Over 160 geotechnical boreholes, many with geophysical logging were executed prior to construction works. The bedrock consists of Paleogene "Copenhagen limestone......The requirement for excavation support can be assessed from face logging. Face logs can also improve our knowledge of lithological and structural conditions within bedrock and supplement information from boreholes and geophysical logs. During the construction of 8 km metro tunnel and 4 km heating....... The induration degrees recorded in face logs and boreholes are compared and correlated. Distinct geophysical log markers are used to divide the limestone into three units. These marker horizons are correlated between face logs and geotechnical boreholes. A 3D model of the strength variations recorded within...

  4. Tucker Wireline Open Hole Wireline Logging; FINAL

    International Nuclear Information System (INIS)

    Milliken, M.

    2002-01-01

    The Tucker Wireline unit ran a suite of open hole logs right behind the RMOTC logging contractor for comparison purposes. The tools included Dual Laterolog, Phased Induction, BHC Sonic, and Density-Porosity

  5. Log-fueled boilers; Les chaudieres a buches

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This document describes the different technologies of wood boilers fueled with logs (ascending combustion and natural draught, horizontal combustion and natural draught, reverse combustion and natural draught, reverse combustion and forced draught), their advantages and drawbacks, selection criteria and installation rules. (J.S.)

  6. Long lasting decontamination foam

    Science.gov (United States)

    Demmer, Ricky L.; Peterman, Dean R.; Tripp, Julia L.; Cooper, David C.; Wright, Karen E.

    2010-12-07

    Compositions and methods for decontaminating surfaces are disclosed. More specifically, compositions and methods for decontamination using a composition capable of generating a long lasting foam are disclosed. Compositions may include a surfactant and gelatin and have a pH of less than about 6. Such compositions may further include affinity-shifting chemicals. Methods may include decontaminating a contaminated surface with a composition or a foam that may include a surfactant and gelatin and have a pH of less than about 6.

  7. Linking log quality with product performance

    Science.gov (United States)

    D. W. Green; Robert Ross

    1997-01-01

    In the United States, log grading procedures use visual assessment of defects, in relation to the log scaling diameter, to estimate the yield of lumber that maybe expected from the log. This procedure was satisfactory when structural grades were based only on defect size and location. In recent years, however, structural products have increasingly been graded using a...

  8. Pacific Rim log trade: determinants and trends.

    Science.gov (United States)

    Donald F. Flora; Andrea L. Anderson; Wendy J. McGinnls

    1991-01-01

    Pacific Rim trade in softwood logs amounts to about $3 billion annually, of which the U.S. share is about $2 billion. Log exporting is a significant part of the forest economy in the Pacific Northwest. The 10 major Pacific Rim log-trading client and competitor countries differ widely in their roles in trade and in their policies affecting the industry.

  9. Well logging radioactive detector assembly

    International Nuclear Information System (INIS)

    Osburn, T.D.

    1992-01-01

    This patent describes a well logging instrument of the type having a radioactive logging sub having a sealed chamber and have a radioactive source for emitting radioactive energy into the well formation, the instrument having a radioactive energy detector for detecting gamma rays resulting from the emission of the radioactive energy into the well formation, and means for pressing the sub against the well of the well, an improved Dewar flask for the detector. It comprises: an inner housing formed of titanium and containing the detector; an outer housing formed of titanium, having a cylindrical side wall surrounding the inner housing and separated by a clearance which is evacuated, the outer housing being located within the sealed chamber in the sub of the instrument; a window section formed in the side wall of the outer housing adjacent the detector and on a side of the side wall closest to the wall of the well when the sub is pressed against the wall of the well; and wherein the inner housing has a cylindrical side wall that is of lesser wall thickness than the wall thickness of the side wall of the outer housing other than in the window section

  10. Timber tree regeneration along abandoned logging roads in a tropical Bolivian forest

    DEFF Research Database (Denmark)

    Nabe-Nielsen, J.; Severiche, W.; Fredericksen, T.

    2007-01-01

    Sustainable management of selectively logged tropical forests requires that felled trees are replaced through increased recruitment and growth. This study compares road track and roadside regeneration with regeneration in unlogged and selectively logged humid tropical forest in north-eastern Boli......Sustainable management of selectively logged tropical forests requires that felled trees are replaced through increased recruitment and growth. This study compares road track and roadside regeneration with regeneration in unlogged and selectively logged humid tropical forest in north......-eastern Bolivia. Some species benefited from increased light intensities on abandoned logging roads. Others benefited from low densities of competing vegetation on roads with compacted soils. This was the case for the small-seeded species Ficus boliviana C.C. Berg and Terminalia oblonga (Ruiz & Pav.) Steud. Some...

  11. Climbers and logging in the Forêt Classée du Haut Sassandra, Côte d'Ivoire.

    NARCIS (Netherlands)

    Kouamé, F.N.; Bongers, F.J.J.M.; Poorter, L.; Traoré, D.

    2004-01-01

    In this study we compare climber abundance and size in centres of post-logging skid tracks and log loading areas to their adjacent relatively undisturbed border zones, in a selectively logged forest in the west-centre of Me d'Ivoire. We also evaluate the effect of time after logging (age) on these

  12. The last universal physicist

    Energy Technology Data Exchange (ETDEWEB)

    Coccia, Eugenio [Gran Sasso National Laboratory, University of Rome ' Tor Vergata' (Italy)]. E-mail coccia@lngs.infn.it

    2005-04-01

    Born in Rome in 1901, Fermi was the last universal physicist - the most extraordinary of his century. He was at home in the workshop, the laboratory and among theoretical physicists. For the theorists he was a great theorist, and for the experimentalists he was a great experimentalist. What made Fermi so special as a physicist was his universality and versatility; what made him so special as a person was his modesty, realism and frugal lifestyle. This book, which describes Fermi's contributions to physics and the US period of his life, originated from a symposium that was held in Chicago in 2001 to commemorate the centenary of his birth. But it is not merely a volume of reminiscences. It combines essays, specially commissioned articles, as well as private material from Fermi's research notebooks, correspondence and speeches. Together the material highlights the breadth of his impact on physics. A classic biographical introduction by Emilio Segre is followed by an article in which Frank Wilczek, who shared the Nobel Prize for Physics last year, puts into perspective Fermi's huge contributions to physics. The list of his achievements is impressive. They include the introduction of Fermi statistics for half-integer-spin particles (1925) - now called fermions - that led to the concept of the 'Fermi surface' in condensed-matter and nuclear physics; the vector-coupling theory for beta-decay (1933), which formulated the proper structure of the weak interaction where the 'Fermi constant' measures the strength of the coupling; and the introduction, with his Rome group, of neutron-induced radioactivity and the study of slow-neutron interactions (1934). As a researcher and a teacher, Fermi inspired two generations and two continents - a man whose charismatic nature attracted many talented scientists and students to Chicago. What emerges from this book is the gratitude of so many extraordinary physicists to their master, who instilled in them

  13. Semi-automatic logarithmic converter of logs

    International Nuclear Information System (INIS)

    Gol'dman, Z.A.; Bondar's, V.V.

    1974-01-01

    Semi-automatic logarithmic converter of logging charts. An original semi-automatic converter was developed for use in converting BK resistance logging charts and the time interval, ΔT, of acoustic logs from a linear to a logarithmic scale with a specific ratio for subsequent combining of them with neutron-gamma logging charts in operative interpretation of logging materials by a normalization method. The converter can be used to increase productivity by giving curves different from those obtained in manual, pointwise processing. The equipment operates reliably and is simple in use. (author)

  14. Well log characterization of natural gas-hydrates

    Science.gov (United States)

    Collett, Timothy S.; Lee, Myung W.

    2012-01-01

    In the last 25 years there have been significant advancements in the use of well-logging tools to acquire detailed information on the occurrence of gas hydrates in nature: whereas wireline electrical resistivity and acoustic logs were formerly used to identify gas-hydrate occurrences in wells drilled in Arctic permafrost environments, more advanced wireline and logging-while-drilling (LWD) tools are now routinely used to examine the petrophysical nature of gas-hydrate reservoirs and the distribution and concentration of gas hydrates within various complex reservoir systems. Resistivity- and acoustic-logging tools are the most widely used for estimating the gas-hydrate content (i.e., reservoir saturations) in various sediment types and geologic settings. Recent integrated sediment coring and well-log studies have confirmed that electrical-resistivity and acoustic-velocity data can yield accurate gas-hydrate saturations in sediment grain-supported (isotropic) systems such as sand reservoirs, but more advanced log-analysis models are required to characterize gas hydrate in fractured (anisotropic) reservoir systems. New well-logging tools designed to make directionally oriented acoustic and propagation-resistivity log measurements provide the data needed to analyze the acoustic and electrical anisotropic properties of both highly interbedded and fracture-dominated gas-hydrate reservoirs. Advancements in nuclear magnetic resonance (NMR) logging and wireline formation testing (WFT) also allow for the characterization of gas hydrate at the pore scale. Integrated NMR and formation testing studies from northern Canada and Alaska have yielded valuable insight into how gas hydrates are physically distributed in sediments and the occurrence and nature of pore fluids(i.e., free water along with clay- and capillary-bound water) in gas-hydrate-bearing reservoirs. Information on the distribution of gas hydrate at the pore scale has provided invaluable insight on the mechanisms

  15. Biological legacies buffer local species extinction after logging.

    Science.gov (United States)

    Rudolphi, Jörgen; Jönsson, Mari T; Gustafsson, Lena; Bugmann, H

    2014-02-01

    Clearcutting has been identified as a main threat to forest biodiversity. In the last few decades, alternatives to clearcutting have gained much interest. Living and dead trees are often retained after harvest to serve as structural legacies to mitigate negative effects of forestry. However, this practice is widely employed without information from systematic before-after control-impact studies to assess the processes involved in species responses after clearcutting with retention. We performed a large-scale survey of the occurrence of logging-sensitive and red-listed bryophytes and lichens before and after clearcutting with the retention approach. A methodology was adopted that, for the first time in studies on retention approaches, enabled monitoring of location-specific substrates. We used uncut stands as controls to assess the variables affecting the survival of species after a major disturbance. In total, 12 bryophyte species and 27 lichen species were analysed. All were classified as sensitive to logging, and most species are also currently red-listed. We found that living and dead trees retained after final harvest acted as refugia in which logging-sensitive species were able to survive for 3 to 7 years after logging. Depending on type of retention and organism group, between 35% and 92% of the species occurrences persisted on retained structures. Most species observed outside retention trees or patches disappeared. Larger pre-harvest population sizes of bryophytes on dead wood increased the survival probability of the species and hence buffered the negative effects of logging. Synthesis and applications . Careful spatial planning of retention structures is required to fully embrace the habitats of logging-sensitive species. Bryophytes and lichens persisted to a higher degree in retention patches compared to solitary trees or in the clearcut area. Retaining groups of trees in logged areas will help to sustain populations of species over the clearcut phase

  16. A Universal Logging System for LHCb Online

    International Nuclear Information System (INIS)

    Nikolaidis, Fotis; Brarda, Loic; Garnier, Jean-Christophe; Neufeld, Niko

    2011-01-01

    A log is recording of system's activity, aimed to help system administrator to traceback an attack, find the causes of a malfunction and generally with troubleshooting. The fact that logs are the only information an administrator may have for an incident, makes logging system a crucial part of an IT infrastructure. In large scale infrastructures, such as LHCb Online, where quite a few GB of logs are produced daily, it is impossible for a human to review all of these logs. Moreover, a great percentage of them as just n oise . That makes clear that a more automated and sophisticated approach is needed. In this paper, we present a low-cost centralized logging system which allow us to do in-depth analysis of every log.

  17. A neutron well logging system

    International Nuclear Information System (INIS)

    1980-01-01

    A pulsed neutron well logging system using a sealed off neutron generator tube is provided with a programmable digital neutron output control system. The control system monitors the target beam current and compares a function of this current with a pre-programmed control function to develop a control signal for the neutron generator. The control signal is used in a series regulator to control the average replenisher current of the neutron generator tube. The programmable digital control system of the invention also provides digital control signals as a function of time to provide ion source voltages. This arrangement may be utilized to control neutron pulses durations and repetition rates or to produce other modulated wave forms for intensity modulating the output of the neutron generator as a function of time. (Auth.)

  18. Decomposable log-linear models

    DEFF Research Database (Denmark)

    Eriksen, Poul Svante

    can be characterized by a structured set of conditional independencies between some variables given some other variables. We term the new model class decomposable log-linear models, which is illustrated to be a much richer class than decomposable graphical models.It covers a wide range of non...... The present paper considers discrete probability models with exact computational properties. In relation to contingency tables this means closed form expressions of the maksimum likelihood estimate and its distribution. The model class includes what is known as decomposable graphicalmodels, which......-hierarchical models, models with structural zeroes, models described by quasi independence and models for level merging. Also, they have a very natural interpretation as they may be formulated by a structured set of conditional independencies between two events given some other event. In relation to contingency...

  19. Well logging, atom and geology

    International Nuclear Information System (INIS)

    Serra, O.

    1994-01-01

    Well logging techniques exploit interactions of gamma photons and neutrons with atoms. Interactions of neutrons of different energies with atoms allow the detection and evaluation of the weight percentage of several elements composing the rocks (C, O, Si, Ca, Fe, S); spectrometry of gamma rays produced by thermal neutron absorption allows for the weight percentage determination of Si, Ca, Fe, S, Cl, H, Ti and Gd, etc. High resolution detectors (germanium doped by Li, at liquid nitrogen temperature) allow the recognition of more elements. Other techniques involving neutrons consist in determining the population in epithermal neutrons at a certain distance of the neutron source (measurement of the hydrogen index). By analyzing the intensity of the gamma flux produced by Compton scattering, the electronic and bulk densities of the rocks are measured. All these data lead to the detection and evaluation of ore deposits (uranium and potassium) and coal, and determination of the lithology, the main minerals composing the rocks, petrophysical properties... 1 fig

  20. Analyzing Decision Logs to Understand Decision Making in Serious Crime Investigations.

    Science.gov (United States)

    Dando, Coral J; Ormerod, Thomas C

    2017-12-01

    Objective To study decision making by detectives when investigating serious crime through the examination of decision logs to explore hypothesis generation and evidence selection. Background Decision logs are used to record and justify decisions made during serious crime investigations. The complexity of investigative decision making is well documented, as are the errors associated with miscarriages of justice and inquests. The use of decision logs has not been the subject of an empirical investigation, yet they offer an important window into the nature of investigative decision making in dynamic, time-critical environments. Method A sample of decision logs from British police forces was analyzed qualitatively and quantitatively to explore hypothesis generation and evidence selection by police detectives. Results Analyses revealed diversity in documentation of decisions that did not correlate with case type and identified significant limitations of the decision log approach to supporting investigative decision making. Differences emerged between experienced and less experienced officers' decision log records in exploration of alternative hypotheses, generation of hypotheses, and sources of evidential inquiry opened over phase of investigation. Conclusion The practical use of decision logs is highly constrained by their format and context of use. Despite this, decision log records suggest that experienced detectives display strategic decision making to avoid confirmation and satisficing, which affect less experienced detectives. Application Potential applications of this research include both training in case documentation and the development of new decision log media that encourage detectives, irrespective of experience, to generate multiple hypotheses and optimize the timely selection of evidence to test them.

  1. Eucalipto, madeira serrada, metodologia de amostragem, regressão multivariada. Log sampling of Eucalyptus grandis trees submitted to selection for sawn timber and energy purposes Amostragem de toras de árvores de Eucalyptus grandis selecionadas para finalidades de serraria e energia

    Directory of Open Access Journals (Sweden)

    Paulo Eduardo Telles dos Santos

    2010-06-01

    Full Text Available By the assessment of ten technological traits of eucalypt wood for sawn timber and energy purposes,
    it was developed a multivariate statistical procedure in order to determine the sequence of logs to be sampled, in such a way to represent all statistical variation contained within the tree and, accordingly, to establish the appropriate sampling intensity. In the present work, it was used a total of 40 logs from four trees of Eucalyptus grandis provenance Concórdia-SC aged 18 years. By using principal components regression analysis and stepwise selection techniques, it was showed that only two logs, corresponding to the first (0.05 m to 2.60 m and fourth (8.85 m to 11.40 m positions into the tree, contained 99.2 % of the total variation detected originally. In the case of adopting a single log, the recommendation was over the fourth log, which represented 97.5 % of the total
    amount of the original variation. For the referred  population, the statistical procedure contributed substantially to reduce the high time-consuming and financial costs that are normally associated to studies oriented to this goal, without affecting the original statistical information exhibited by the whole group of logs that would be usually sampled.A partir da avaliação de dez características tecnológicas de madeira de eucalipto para fins de serraria e energia, desenvolveu-se procedimento estatístico multivariado para se determinar a seqüência de toras a ser amostrada, de forma a representar acumuladamente toda a variação estatística presente na árvore e, com isso, estabelecer a intensidade adequada de amostragem. Neste estudo, foram utilizadas 40 toras oriundas de quatro árvores de Eucalyptus grandis aos 18 anos de idade procedentes de Concórdia, SC. Com o uso de técnicas de regressão multivariada de componentes principais e seleção por etapas, chegou-se à conclusão que amostrandose apenas duas toras, correspondentes à primeira (0,05 m a 2

  2. MEXFAM's 'The Last Train'.

    Science.gov (United States)

    1988-01-01

    One of the short educational video programs produced by MEXFAM is called The Last Train, a love story of 2 teenagers which vividly describes the type of adolescent problems confronting Mexican society today. The film raises a number of questions which teenagers do not often consider. The objective of the film is to put in evidence the principles, myths, beliefs, omissions, and misinformation that exist between youth and adults regarding early genital urges. The movie aims to reach underprivileged urban youth between the ages of 11 and 20 years, as well as teachers and parents who are sensitive to youth's sex problems. MEXFAM emphasizes that the educational objective of the film should be pointed out to its audiences before it is shown. After the screening the main points recommended for discussion are: genital attraction, physical control, masturbation, virginity, and 1st sexual experience. MEXFAM also provides audiences with values sheets on which the participants are to write their reactions to certain situations in the film.

  3. The Last Straw

    CERN Multimedia

    McFarlane, K.W.

    2002-01-01

    On 4 December 2002 at Hampton University, we completed processing the 'straws' for the Barrel TRT. The straws are plastic tubes 4 mm in diameter and 1.44 m long. More than 52 thousand straws will be used to build the drift tube detectors in the Barrel TRT. The picture shows some members of the Hampton production team ceremonially cutting the last straw to its final precise length. The production team, responsible for processing 64 thousand straws, included Jacquelyn Hodges, Carolyn Griffin, Princess Wilkins, Aida Kelly, Alan Fry, and (not pictured) Chuck Long, Nedra Peeples, and Hilda Williams. The straws have a cosmopolitan history. First, plastic film from a U.S. company was shipped to Russia to be coated with conductive materials and adhesive. The coated film was slit into long ribbons and sent to the UK to be wound into tubes. The tubes were then sent to two ATLAS collaborators in Russia, PNPI (Gatchina) and JINR (Dubna), where they were reinforced with carbon fibres to make them stiff and accuratel...

  4. The last glacial maximum

    Science.gov (United States)

    Clark, P.U.; Dyke, A.S.; Shakun, J.D.; Carlson, A.E.; Clark, J.; Wohlfarth, B.; Mitrovica, J.X.; Hostetler, S.W.; McCabe, A.M.

    2009-01-01

    We used 5704 14C, 10Be, and 3He ages that span the interval from 10,000 to 50,000 years ago (10 to 50 ka) to constrain the timing of the Last Glacial Maximum (LGM) in terms of global ice-sheet and mountain-glacier extent. Growth of the ice sheets to their maximum positions occurred between 33.0 and 26.5 ka in response to climate forcing from decreases in northern summer insolation, tropical Pacific sea surface temperatures, and atmospheric CO2. Nearly all ice sheets were at their LGM positions from 26.5 ka to 19 to 20 ka, corresponding to minima in these forcings. The onset of Northern Hemisphere deglaciation 19 to 20 ka was induced by an increase in northern summer insolation, providing the source for an abrupt rise in sea level. The onset of deglaciation of the West Antarctic Ice Sheet occurred between 14 and 15 ka, consistent with evidence that this was the primary source for an abrupt rise in sea level ???14.5 ka.

  5. California-Nevada uranium logging. Final report

    International Nuclear Information System (INIS)

    1981-04-01

    The purpose of this project was to obtain geophysical logs of industry drill holes to assess the uranium resource potential of geologic formations of interest. The work was part of the US Department of Energy's National Uranium Resource Evaluation (NURE) Program. The principal objective of the logging program was to determine radioelement grade of formations through natural gamma ray detectors. Supplementary information was obtained from resistivity (R), self-potential (SP), point resistance (RE), and neutron density (NN) logs for formation interpretation. Additional data for log interpretation was obtained from caliper logs, casing schedules, and downhole temperature. This data was obtained from well operators when available, with new logs obtained where not formerly available. This report contains a summary of the project and data obtained to date

  6. Pembangkitan Data dari Distribusi Log-logistik

    Directory of Open Access Journals (Sweden)

    Aceng Komarudin Mutaqin

    2014-11-01

    Full Text Available Distribusi log-logistik merupakan salah satu distribusi yang dapat diaplikasikan untuk data mutu lingkungan. Makalah ini membahas pembangkitan data dari distribusi log-logistik mulai dari pembangunan algoritme sampai pembuatan program komputer pada perangkat lunak MATLAB. Metode pembangkitan datanya menggunakan metode inverse transform. Ada dua jenis data yang dibangkitkan, yaitu data lengkap dan data tersensor kiri. Dalam makalah ini diberikan contoh data yang dibangkitkan dari distribusi log-logistik.

  7. SNG-logs at the Bagsvaerd Lake

    International Nuclear Information System (INIS)

    Korsbech, U.

    1992-11-01

    Spectral Natural Gamma-logs (SNG) were taken in old boreholes around Bagsvaerd Lake (Zealand). The purpose of this investigation was to clarify the geologic/lithologic conditions in this region and the potential risks of waste penetration into ground water. Relationship curves for thorium, uranium and potassium concentrations are given. Some special logs which can be useful for evaluating concentration variations or transition forms among various lithological layers are collected. Appendices contain technical information on the boreholes and discussion of differences between results of SNG-logging and the conventional gamma-logging. (EG)

  8. Efeito da colheita seletiva de madeira sobre algumas características físicas de um latossolo amarelo sob floresta na Amazônia Central Effect of selective logging on some physical characteristics of a yellow latosol under rainforest in Central Amazonia State

    Directory of Open Access Journals (Sweden)

    Walane Maria Pereira de Mello-Ivo

    2006-10-01

    Full Text Available A colheita seletiva de madeira pode vir a ser uma forma sustentável de uso da terra para ecossistemas florestais da Amazônia, uma vez que permite a manutenção de parte considerável da biomassa florestal, diminuindo, assim, a perturbação nas áreas exploradas. Neste sentido, o presente estudo teve como objetivo avaliar o efeito da exploração seletiva de madeira sobre as características físicas de um Latossolo Amarelo. A área de estudo localiza-se a cerca de 80 km ao norte de Manaus e a vegetação é do tipo Floresta Ombrófila Densa. O número de árvores retiradas com um trator de esteiras D6, por arraste, em 1993, variou de sete a dez árvores/ha (DAP > 55 cm. O delineamento experimental foi do tipo blocos ao acaso, com três repetições. Seis tratamentos foram avaliados, equivalendo às seguintes classes de perturbação identificadas na área: trilha de trator, centro de clareira, borda da clareira/floresta, borda da floresta/clareira, floresta remanescente e floresta-controle. A colheita seletiva de madeira provocou modificações nas características físicas do solo, principalmente nas trilhas de trator, e representou, em média, 13,8 % da área total explorada. Os valores de densidade do solo e resistência à penetração foram maiores para o solo sob estas áreas, enquanto a macroporosidade e o volume de água disponível para as plantas apresentaram-se menores do que nas demais classes de perturbação. Estas classes foram menos afetadas, não se estabelecendo diferenças significativas para as características físicas do solo entre estas e a floresta-controle, indicando, assim, a colheita seletiva como uma prática de menor impacto para o solo dos ecossistemas florestais da Amazônia.Selective logging may become a form of sustainable use of Amazon forest ecosystems since most part of the forest biomass is maintained and the impacts on the exploited area are lower than in comparison to those under other land uses. The

  9. Daedalus - Last Dryden flight

    Science.gov (United States)

    1988-01-01

    The Daedalus 88, with Glenn Tremml piloting, is seen here on its last flight for the NASA Dryden Flight Research Center, Edwards, California. The Light Eagle and Daedalus human powered aircraft were testbeds for flight research conducted at Dryden between January 1987 and March 1988. These unique aircraft were designed and constructed by a group of students, professors, and alumni of the Massachusetts Institute of Technology within the context of the Daedalus project. The construction of the Light Eagle and Daedalus aircraft was funded primarily by the Anheuser Busch and United Technologies Corporations, respectively, with additional support from the Smithsonian Air and Space Museum, MIT, and a number of other sponsors. To celebrate the Greek myth of Daedalus, the man who constructed wings of wax and feathers to escape King Minos, the Daedalus project began with the goal of designing, building and testing a human-powered aircraft that could fly the mythical distance, 115 km. To achieve this goal, three aircraft were constructed. The Light Eagle was the prototype aircraft, weighing 92 pounds. On January 22, 1987, it set a closed course distance record of 59 km, which still stands. Also in January of 1987, the Light Eagle was powered by Lois McCallin to set the straight distance, the distance around a closed circuit, and the duration world records for the female division in human powered vehicles. Following this success, two more aircraft were built, the Daedalus 87 and Daedalus 88. Each aircraft weighed approximately 69 pounds. The Daedalus 88 aircraft was the ship that flew the 199 km from the Iraklion Air Force Base on Crete in the Mediterranean Sea, to the island of Santorini in 3 hours, 54 minutes. In the process, the aircraft set new records in distance and endurance for a human powered aircraft. The specific areas of flight research conducted at Dryden included characterizing the rigid body and flexible dynamics of the Light Eagle, investigating sensors for an

  10. 32 CFR 700.846 - Status of logs.

    Science.gov (United States)

    2010-07-01

    ... Officers Afloat § 700.846 Status of logs. The deck log, the engineering log, the compass record, the bearing hooks, the engineer's bell book, and any records generated by automated data logging equipment...

  11. Influence of borehole-eccentred tools on wireline and logging-while-drilling sonic logging measurements

    KAUST Repository

    Pardo, David; Matuszyk, Paweł Jerzy; Torres-Verdí n, Carlos; Mora Cordova, Angel; Muga, Ignacio; Calo, Victor M.

    2013-01-01

    We describe a numerical study to quantify the influence of tool-eccentricity on wireline (WL) and logging-while-drilling (LWD) sonic logging measurements. Simulations are performed with a height-polynomial-adaptive (hp) Fourier finite-element method

  12. Log canonical thresholds of smooth Fano threefolds

    International Nuclear Information System (INIS)

    Cheltsov, Ivan A; Shramov, Konstantin A

    2008-01-01

    The complex singularity exponent is a local invariant of a holomorphic function determined by the integrability of fractional powers of the function. The log canonical thresholds of effective Q-divisors on normal algebraic varieties are algebraic counterparts of complex singularity exponents. For a Fano variety, these invariants have global analogues. In the former case, it is the so-called α-invariant of Tian; in the latter case, it is the global log canonical threshold of the Fano variety, which is the infimum of log canonical thresholds of all effective Q-divisors numerically equivalent to the anticanonical divisor. An appendix to this paper contains a proof that the global log canonical threshold of a smooth Fano variety coincides with its α-invariant of Tian. The purpose of the paper is to compute the global log canonical thresholds of smooth Fano threefolds (altogether, there are 105 deformation families of such threefolds). The global log canonical thresholds are computed for every smooth threefold in 64 deformation families, and the global log canonical thresholds are computed for a general threefold in 20 deformation families. Some bounds for the global log canonical thresholds are computed for 14 deformation families. Appendix A is due to J.-P. Demailly.

  13. Aggregation of log-linear risks

    DEFF Research Database (Denmark)

    Embrechts, Paul; Hashorva, Enkeleijd; Mikosch, Thomas Valentin

    2014-01-01

    In this paper we work in the framework of a k-dimensional vector of log-linear risks. Under weak conditions on the marginal tails and the dependence structure of a vector of positive risks, we derive the asymptotic tail behaviour of the aggregated risk {and present} an application concerning log...

  14. Synthetic rope applications in Appalachian logging

    Science.gov (United States)

    Ben D. Spong; Jingxin Wang

    2008-01-01

    New ultra-high molecular weight polyethylene rope has shown good results as a replacement for wire rope in logging applications in the western United States. A single case study trial was performed in Appalachian forest conditions to assess the appropriateness of this technology for hardwood logging applications. The study focused on use of the rope in West Virginia...

  15. Palm distributions for log Gaussian Cox processes

    DEFF Research Database (Denmark)

    Coeurjolly, Jean-Francois; Møller, Jesper; Waagepetersen, Rasmus

    This paper reviews useful results related to Palm distributions of spatial point processes and provides a new result regarding the characterization of Palm distributions for the class of log Gaussian Cox processes. This result is used to study functional summary statistics for a log Gaussian Cox...

  16. Log-binomial models: exploring failed convergence.

    Science.gov (United States)

    Williamson, Tyler; Eliasziw, Misha; Fick, Gordon Hilton

    2013-12-13

    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. 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. 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.

  17. LHCb Online Log Analysis and Maintenance System

    CERN Document Server

    Garnier, J-C

    2011-01-01

    History has shown, many times computer logs are the only information an administrator may have for an incident, which could be caused either by a malfunction or an attack. Due to the huge amount of logs that are produced from large-scale IT infrastructures, such as LHCb Online, critical information may be overlooked or simply be drowned in a sea of other messages. This clearly demonstrates the need for an automatic system for long-term maintenance and real time analysis of the logs. We have constructed a low cost, fault tolerant centralized logging system which is able to do in-depth analysis and cross-correlation of every log. This system is capable of handling O(10000) different log sources and numerous formats, while trying to keep the overhead as low as possible. It provides log gathering and management, Offline analysis and online analysis. We call Offline analysis the procedure of analyzing old logs for critical information, while Online analysis refer to the procedure of early alerting and reacting. ...

  18. The nuclear magnetic resonance well logging

    International Nuclear Information System (INIS)

    Zhang Yumin; Shen Huitang

    2003-01-01

    In this paper, the characteristic of the nuclear magnetic resonance logging is described at first. Then its development and its principle is presented. Compared with the nuclear magnetic resonance spectrometer, the magnet techniques is the first question that we must solve in the manufacture of the NMR well logging

  19. A semantic perspective on query log analysis

    NARCIS (Netherlands)

    Hofmann, K.; de Rijke, M.; Huurnink, B.; Meij, E.

    2009-01-01

    We present our views on the CLEF log file analysis task. We argue for a task definition that focuses on the semantic enrichment of query logs. In addition, we discuss how additional information about the context in which queries are being made could further our understanding of users’ information

  20. Utilization and cost for animal logging operations

    Science.gov (United States)

    Suraj P. Shrestha; Bobby L. Lanford

    2001-01-01

    Forest harvesting with animals is a labor-intensive operation. Due to the development of efficient machines and high volume demands from the forest products industry, mechanization of logging developed very fast, leaving behind the traditional horse and mule logging. It is expensive to use machines on smaller woodlots, which require frequent moves if mechanically...

  1. Data logging system upgrade for Indus accelerator

    International Nuclear Information System (INIS)

    Mishra, R.; Merh, B.N.; Agrawal, R.K.; Fatnani, P.; Navathe, C.P.; Pal, S.

    2012-01-01

    An accelerator has various subsystems like Magnet Power Supply, Beam Diagnostics and Vacuum etc. which are required to work in a stable manner to ensure required machine performance. Logging of system parameters at a faster rate plays a crucial role in analysing and understanding machine behaviour. Logging all the machine parameters consistently at the rate of typically more than 1 Hz has been the aim of a recent data logging system upgrade. Nearly ten thousand parameters are being logged at varying intervals of one second to one minute in Indus accelerator complex. The present logging scheme is augmented to log all these parameters at a rate equal to or more than 1 Hz. The database schema is designed according to the data type of the parameter. The data is distributed into historical table and intermediate table which comprises of recent data. Machine control applications read the parameter values from the control system and store them into the text files of finite time duration for each sub-system. The logging application of each sub-system passes these text files to database for bulk insertion. The detail design of database, logging scheme and its architecture is presented in the paper. (author)

  2. Neutron logging reliability techniques and apparatus

    International Nuclear Information System (INIS)

    Johnstone, C.W.

    1978-01-01

    This invention relates in general to neutron logging of earth formations, and in particular, to novel apparatus and procedures for determining the validity, or reliability, of data derived at least in part by logging neutron characteristics of earth formations and, if desired, for affording verifiably accurate indications of such data

  3. Neutron logging reliability techniques and apparatus

    International Nuclear Information System (INIS)

    Johnstone, C.W.

    1974-01-01

    This invention relates in general to neutron logging of earth formations, and in particular, to novel apparatus and procedures for determining the validity, or reliability, of data derived at least in part by logging neutron characteristics of earth formations and, if desired, for affording verifiably accurate indications of such data. (author)

  4. Logging methods and peeling of Aspen

    Science.gov (United States)

    T. Schantz-Hansen

    1948-01-01

    The logging of forest products is influenced by many factors, including the size of the trees, density of the stand, the soundness of the trees, size of the area logged, topography and soil, weather conditions, the degree of utilization, the skill of the logger and the equipment used, the distance from market, etc. Each of these factors influences not only the method...

  5. Grading sugar pine saw logs in trees.

    Science.gov (United States)

    John W. Henley

    1972-01-01

    Small limbs and small overgrown limbs cause problems when grading saw logs in sugar pine trees. Surface characteristics and lumber recovery information for 426 logs from 64 sugar pine trees were examined. Resulting modifications in the grading specification that allow a grader to ignore small limbs and small limb indicators do not appear to decrease the performance of...

  6. Necromass in undisturbed and logged forests in the Brazilian Amazon.

    Science.gov (United States)

    Michael Palace; Michael Keller; Gregory P. Asner; Jose Natalino M. Silva; Carlos. Passos

    2007-01-01

    Necromass is an important stock of carbon in tropical forests. We estimated volume, density, and mass of fallen and standing necromass in undisturbed and selectively logged forests at Juruena, Mato Grosso, Brazil (10.488S, 58.478W). We also measured standing dead trees at the Tapajos National Forest, Para, Brazil (3.088S, 54.948W) complementing our earlier study there...

  7. Model wells for nuclear well logging

    International Nuclear Information System (INIS)

    Tittle, C.W.

    1989-01-01

    Considerations needed in the design and construction of model wells for nuclear log calibration are covered, with special attention to neutron porosity logging and total γ-ray logging. Pulsed neutron decay-time and spectral γ-ray logging are discussed briefly. The American Petroleum Institute calibration facility for nuclear logs is a good starting point for similar or expanded facilities. A few of its shortcomings are mentioned; they are minor. The problem of fluid saturation is emphasized. Attention is given to models made of consolidated rock and those containing unconsolidated material such as Ottawa sand. Needed precautions are listed. A similarity method is presented for estimating the porosity index of formations that are not fully saturated. (author)

  8. Processing of gamma-ray spectrometric logs

    International Nuclear Information System (INIS)

    Umiastowski, K.; Dumesnil, P.

    1984-10-01

    CEA (Commissariat a l'Energie Atomique) has developped a gamma-ray spectrometric tool, containing an analog-to-digital converter. This new tool permits to perform very precise uranium logs (natural gamma-ray spectrometry), neutron activation logs and litho-density logs (gamma-gamma spectrometric logs). Specific processing methods were developped to treate the particular problems of down-hole gamma-ray spectrometry. Extraction of the characteristic gamma-ray peak, even if they are superposed on the background radiation of very high intensity, is possible. This processing methode enables also to obtain geological informations contained in the continuous background of the spectrum. Computer programs are written in high level language for SIRIUS (VICTOR) and APOLLO computers. Exemples of uranium and neutron activation logs treatment are presented [fr

  9. LOG2MARKUP: State module to transform a Stata text log into a markup document

    DEFF Research Database (Denmark)

    2016-01-01

    log2markup extract parts of the text version from the Stata log command and transform the logfile into a markup based document with the same name, but with extension markup (or otherwise specified in option extension) instead of log. The author usually uses markdown for writing documents. However...

  10. Processing well logging data, for example for verification and calibration of well logs

    International Nuclear Information System (INIS)

    Suau, J.; Boutemy, Y.

    1981-01-01

    A method is described of machine processing well logging data derived from borehole exploring devices which investigate earth formations traversed by boreholes. The method can be used for verifying and recalibrating logs, reconstructing missing logs and combining the data to form a statistical model of the traversed earth formations. (U.K.)

  11. Analysis of Web Server Log Files: Website of Information Management Department of Hacettepe University

    Directory of Open Access Journals (Sweden)

    Mandana Mir Moftakhari

    2015-09-01

    Full Text Available Over the last decade, the importance of analysing information management systems logs has grown, because it has proved that results of the analysing log data can help developing in information system design, interface and architecture of websites. Log file analysis is one of the best ways in order to understand information-searching process of online searchers, users’ needs, interests, knowledge, and prejudices. The utilization of data collected in transaction logs of web search engines helps designers, researchers and web site managers to find complex interactions of users’ goals and behaviours to increase efficiency and effectiveness of websites. Before starting any analysis it should be observed that the log file of the web site contain enough information, otherwise analyser wouldn’t be able to create complete report. In this study we evaluate the website of Information Management Department of Hacettepe University by analysing the server log files. Results show that there is not adequate amount of information in log files which are provided by web site server. The reports which we have created have some information about users’ behaviour and need but they are not sufficient for taking ideal decisions about contents & hyperlink structure of website. It also provides that creating an extended log file is essential for the website. Finally we believe that results can be helpful to improve, redesign and create better website.

  12. A Multi-temporal Analysis of Logging Impacts on Tropical Forest Structure Using Airborne Lidar Data

    Science.gov (United States)

    Keller, M. M.; Pinagé, E. R.; Duffy, P.; Longo, M.; dos-Santos, M. N.; Leitold, V.; Morton, D. C.

    2017-12-01

    The long-term impacts of selective logging on carbon cycling and ecosystem function in tropical-forests are still uncertain. Despite improvements in selective logging detection using satellite data, quantifying changes in forest structure from logging and recovery following logging is difficult using orbital data. We analyzed the dynamics of forest structure comparing logged and unlogged forests in the Eastern Brazilian Amazon (Paragominas Municipality, Pará State) using small footprint discrete return airborne lidar data acquired in 2012 and 2014. Logging operations were conducted at the 1200 ha study site from 2006 through 2013 using reduced impact logging techniques—management practices that minimize canopy and ground damage compared to more common conventional logging. Nevertheless, logging still reduced aboveground biomass by 10% to 20% in logged areas compared to intact forests. We aggregated lidar point-cloud data at spatial scales ranging from 50 m to 250 m and developed a binomial classification model based on the height distribution of lidar returns in 2012 and validated the model against the 2014 lidar acquisition. We accurately classified intact and logged forest classes compared with field data. Classification performance improved as spatial resolution increased (AUC = 0.974 at 250 m). We analyzed the differences in canopy gaps, understory damage (based on a relative density model), and biomass (estimated from total canopy height) of intact and logged classes. As expected, logging greatly increased both canopy gap formation and understory damage. However, while the area identified as canopy gap persisted for at least 8 years (from the oldest logging treatments in 2006 to the most recent lidar acquisition in 2014), the effects of ground damage were mostly erased by vigorous understory regrowth after about 5 years. The rate of new gap formation was 6 to 7 times greater in recently logged forests compared to undisturbed forests. New gaps opened at a

  13. Efeitos da exploração madeireira de baixo impacto sobre uma comunidade de aves de sub-bosque na Floresta Nacional do Tapajós, Pará, Brasil Effects of low impact selective logging on an understory bird community in the Tapajós National Forest, Pará, Brazil

    Directory of Open Access Journals (Sweden)

    Luiza Magalli Pinto Henriques

    2008-01-01

    Full Text Available Este estudo compara a resposta de uma comunidade aves à exploração madeireira de baixo impacto através da distribuição das espécies em floresta controle e manejada ao longo de cinco anos com amostragem pré e pós-exploração. O procedimento de ordenação mostrou que a similaridade da comunidade de aves após a exploração madeireira foi menor que a similaridade entre as amostras do período de pré-exploração. Além disso, a ordem das abundâncias das 43 espécies mais comuns foi alterada entre o período anterior à exploração e 3 a 4 anos após a exploração na floresta manejada. A exploração afetou as taxas de captura de 20 espécies, diretamente ou através de uma interação com o tempo. Os insetívoros terrícolas e os insetívoros que seguem bandos mistos foram as guildas mais afetadas pela exploração madeireira. Ambas as guildas mostraram declínio, correlacionado com o tempo, em suas abundâncias em floresta manejada. Insetívoros seguidores de formigas e insetívoros arborícolas não apresentaram diferenças entre a floresta manejada e controle, apesar de algumas espécies dessas guildas terem apresentado efeitos relacionados ao manejo florestal, diretamente ou através de uma interação entre o tempo e o manejo. Frugívoros também não apresentaram efeitos significativos relacionados ao manejo florestal. Nectarívoros aumentaram tanto na floresta explorada como na floresta controle. Efeitos temporais de aumento ou declínio observados em guildas e em 12 espécies ocorreram tanto na floresta controle como na floresta explorada. Este resultado sugere que mudanças temporais na área explorada podem estar relacionadas à sucessão enquanto que mudanças temporais na floresta controle podem estar relacionados à exploração com intensidade de 40m³/ha de parcelas adjacentes.This study compares the avian response to low impact selective logging by comparing bird species distribution in control and cut forest during

  14. Logística del transporte

    OpenAIRE

    Robusté Antón, Francesc

    2005-01-01

    La logística se ha conformado como un proceso estratégico para organizar las actividades de producción y de distribución de las empresas. El concepto de sistema logístico ha incluido un amplio espectro de operaciones que condicionan la eficiencia y la competitividad empresarial en el actual contexto de globalización de la economía. En este sentido, este libro afronta y analiza los distintos aspectos que inciden en los procesos de planificación y gestión de los procesos logísticos relacionados...

  15. Nonblocking and orphan free message logging protocols

    Science.gov (United States)

    Alvisi, Lorenzo; Hoppe, Bruce; Marzullo, Keith

    1992-12-01

    Currently existing message logging protocols demonstrate a classic pessimistic vs. optimistic tradeoff. We show that the optimistic-pessimistic tradeoff is not inherent to the problem of message logging. We construct a message-logging protocol that has the positive features of both optimistic and pessimistic protocol: our protocol prevents orphans and allows simple failure recovery; however, it requires no blocking in failure-free runs. Furthermore, this protocol does not introduce any additional message overhead as compared to one implemented for a system in which messages may be lost but processes do not crash.

  16. Supply of Rubber Wood Log in Malaysia

    OpenAIRE

    Noraida, A. W.; Abdul-Rahim, A. S.

    2014-01-01

    Issue on shortage of raw material for wood processing solved by discovery of rubber wood log as one of the substitutes the natural log. This paper examines the supply of rubber wood log in Malaysia. We employ ARDL Bound Approach Test and time series data from 1980 to 2010 which represented the whole Malaysia are used to achieve the established objectives. The result shown, in the long run harvested area and wages have 1% and 10% significant level respectively. While in the short run, there wa...

  17. Carbon emissions from tropical forest degradation caused by logging

    International Nuclear Information System (INIS)

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

    2014-01-01

    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

  18. Drilling and logging in uranium exploration

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    The report reviews drilling and logging practices in exploration of uranium ores and summarizes the papers presented in the panel meeting. Recommendations for further research and development are given

  19. Neutron logging reliability techniques and apparatus

    International Nuclear Information System (INIS)

    Johnstone, C.W.

    1975-01-01

    Apparatus and methods for verifying the validity of data derived at least in part by neutron logging of earth formations, and, where indicated, for affording neutron diffusion-corrected values of such data, are disclosed. (WHK)

  20. Nuclear log interpretation by first principle

    International Nuclear Information System (INIS)

    Oelgaard, P.L.

    1988-07-01

    A weakness connected to the present interpretation of nuclear borehole logs is that the interdependence of the various logs and physical effects of importance for the tools are not always taken into account in a correct way. Therefore a new approach to the interpretation of nuclear borehole logs is considered. It is based on the logs obtained with the natural gamma, the neutron porosity, the gamma density, and the pulsed neutron tools. For each of these tools a model, taking into account the important physical effects, is established. These models are incorporated into a computer programme which from the tool signals calculates, by use of iteration, a consistent set of the corresponding formation properties. In the paper the models developed for the four tools and the interpretation programme are briefly described. An example of the use of the interpretation programme is given and compared with a conventional interpretation. (author)

  1. LATTE - Log and Time Tracking for Elections

    Data.gov (United States)

    Office of Personnel Management — LATTE - Log and Time Tracking for Elections is a time tracking and voucher preparation system used to schedule employees to cover elections, to document their time...

  2. Well Logging Equipment Updated in China

    Institute of Scientific and Technical Information of China (English)

    Xu Lili

    1996-01-01

    @@ As one of the ten principal disciplines in the petroleum industry, well logging has been developed for about 55years in China and is playing an increasingly important role in the country's oil and gas exploration and development.

  3. Conversation Threads Hidden within Email Server Logs

    Science.gov (United States)

    Palus, Sebastian; Kazienko, Przemysław

    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..

  4. Nuclear borehole logging for oil exploration

    International Nuclear Information System (INIS)

    Oelgaard, P.L.

    1989-01-01

    Reactor physics can be applied to the logging of boreholes for the exploration of oil and gas and the results obtained can be interpreted more correctly by use of reactor physics models, e.g. one-dimensional multi-group diffusion theory adapted for gamma quanta. The standard nuclear logging tools are: natural gamma, gamma density, neutron porosity and the pulsed-neutron tool. The models and interpretation procedures are discussed. 1 fig

  5. Geophysical logging of the Harwell boreholes

    International Nuclear Information System (INIS)

    Brightman, M.A.

    1983-08-01

    A comprehensive geophysical borehole logging survey was carried out on each of three deep boreholes drilled at the Harwell research site. KOALA and PETRA computer programs were used to analyse and interpret the logs to obtain continuous quantitative estimates of the geological and hydrogeological properties of the sequences penetrated at the Harwell site. Quantitative estimates of the mineral composition and porosity of the cores samples were made. (UK)

  6. Defect core detection in radiata pine logs

    International Nuclear Information System (INIS)

    Wallace, G.

    1993-01-01

    Internal defect cores in Pinus radiata logs arise primarily from the practice in New Zealand of pruning trees to increase the amount of clear wood. Realising the benefits of this practice when milling the logs is hampered by the lack of a practical method for detecting the defect cores. This report attempts to establish industry requirements for detections and examine techniques which may be suitable. Some trials of a novel technique are described. (author) 19 refs.; 11 figs

  7. Geophysical borehole logging. Final disposal of spent fuel

    International Nuclear Information System (INIS)

    Rouhiainen, P.

    1984-01-01

    Teollisuuden Voima Oy (Industrial Power Company Ltd.) will take precautions for final disposal of spent fuel in the Finnish bedrock. The first stage of the site selection studies includes drilling of a deep borehole down to approximately 1000 meters in the year 1984. The report deals with geophysical borehole logging methods, which could be used for the studies. The aim of geophysical borehole logging methods is to descripe specially hydrogeological and structural features. Only the most essential methods are dealt with in this report. Attention is paid to the information produced with the methods, derscription of the methods, interpretation and limitations. The feasibility and possibilities for the aims are evaluated. The evaluations are based mainly on the results from Sweden, England, Canada and USA as well as experiencies gained in Finland

  8. Combination thermal and radiation shield for well logging apparatus

    International Nuclear Information System (INIS)

    Wilson, B.F.

    1984-01-01

    A device for providing both thermal protection and radiation shielding for components such as radiation detectors within a well logging instrument comprises a thermally insulative flask containing a weldment filled with a mass of eutectic material which undergoes a change of state e.g. melting at a temperature which will provide an acceptable thermal environment for such components for extended time periods. The eutectic material which is preferably a bismuth (58%)/tin (42%) alloy has a specific gravity (> 8.5) facilitating its use as a radiation shield and is distributed around the radiation detectors so as to selectively impede the impinging of the detectors by radiation. The device is incorporated in a skid of a well logging instrument for measuring γ backscatter. A γ source is located either above or within the protective shielding. (author)

  9. Modeling Precipitation Extremes using Log-Histospline

    Science.gov (United States)

    Huang, W. K.; Nychka, D. W.; Zhang, H.

    2017-12-01

    One of the commonly used approaches to modeling univariate extremes is the peaks-overthreshold (POT) method. The POT method models exceedances over a (sufficiently high/low) threshold as a generalized Pareto distribution (GPD). To apply this method, a threshold has to be chosen and the estimates might be sensitive to the chosen threshold. Here we propose an alternative, the "Log-Histospline", to explore modeling the tail behavior and the remainder of the density in one step using the full range of the data. Log-Histospline applies a smoothing spline model on a finely binned histogram of the log transformed data to estimate its log density. By construction, we are able to preserve the polynomial upper tail behavior, a feature commonly observed in geophysical observations. The Log-Histospline can be extended to the spatial setting by treating the marginal (log) density at each location as spatially indexed functional data, and perform a dimension reduction and spatial smoothing. We illustrate the proposed method by analyzing precipitation data from regional climate model output (North American Regional Climate Change and Assessment Program (NARCCAP)).

  10. The last line effect explained

    NARCIS (Netherlands)

    Beller, M. (Moritz); Zaidman, A. (Andy); Karpov, A. (Andrey); R.A. Zwaan (Rolf)

    2017-01-01

    textabstractMicro-clones are tiny duplicated pieces of code; they typically comprise only few statements or lines. In this paper, we study the “Last Line Effect,” the phenomenon that the last line or statement in a micro-clone is much more likely to contain an error than the previous lines or

  11. The last line effect explained

    NARCIS (Netherlands)

    Beller, M.M.; Zaidman, A.E.; Karpov, Andrey; Zwaan, Rolf A.

    Micro-clones are tiny duplicated pieces of code; they typically comprise only few statements or lines. In this paper, we study the “Last Line Effect,” the phenomenon that the last line or statement in a micro-clone is much more likely to contain an error than the previous lines or statements. We do

  12. The impact of tropical forest logging and oil palm agriculture on the soil microbiome.

    Science.gov (United States)

    Tripathi, Binu M; Edwards, David P; Mendes, Lucas William; Kim, Mincheol; Dong, Ke; Kim, Hyoki; Adams, Jonathan M

    2016-05-01

    Selective logging and forest conversion to oil palm agriculture are rapidly altering tropical forests. However, functional responses of the soil microbiome to these land-use changes are poorly understood. Using 16S rRNA gene and shotgun metagenomic sequencing, we compared composition and functional attributes of soil biota between unlogged, once-logged and twice-logged rainforest, and areas converted to oil palm plantations in Sabah, Borneo. Although there was no significant effect of logging history, we found a significant difference between the taxonomic and functional composition of both primary and logged forests and oil palm. Oil palm had greater abundances of genes associated with DNA, RNA, protein metabolism and other core metabolic functions, but conversely, lower abundance of genes associated with secondary metabolism and cell-cell interactions, indicating less importance of antagonism or mutualism in the more oligotrophic oil palm environment. Overall, these results show a striking difference in taxonomic composition and functional gene diversity of soil microorganisms between oil palm and forest, but no significant difference between primary forest and forest areas with differing logging history. This reinforces the view that logged forest retains most features and functions of the original soil community. However, networks based on strong correlations between taxonomy and functions showed that network complexity is unexpectedly increased due to both logging and oil palm agriculture, which suggests a pervasive effect of both land-use changes on the interaction of soil microbes. © 2016 John Wiley & Sons Ltd.

  13. La logística integral como ventaja competitiva y sistema logístico

    Directory of Open Access Journals (Sweden)

    Mario Anselmo Martínez gallardo

    2013-07-01

    Full Text Available Esta investigación analiza la logística integral como una ventaja competitiva y el sistema logístico. Es opinión de los autores que la logística integral es esencial para el intercambio de mercancías, toda vez que reduce costos y hace más ágil la actividad comercial. La utilización de esta logística representa una ventaja competitiva con respecto de otras empresas por la optimización del capital y ahorro de tiempo.

  14. AML (Advanced Mud Logging: First Among Equals

    Directory of Open Access Journals (Sweden)

    T. Loermans

    2017-09-01

    Full Text Available During the past ten years an enormous development in mud logging technology has been made. Traditional mud logging was only qualitative in nature, and mudlogs could not be used for the petrophysical well evaluations which form the basis for all subsequent activities on wells and fields. AML however can provide quantitative information, logs with a reliability, trueness and precision like LWD and WLL. Hence for well evaluation programmes there are now three different logging methods available, each with its own pros and cons on specific aspects: AML, LWD and WLL. The largest improvements have been made in mud gas analysis and elemental analysis of cuttings. Mud gas analysis can yield hydrocarbon fluid composition for some components with a quality like PVT analysis, hence not only revolutionising the sampling programme so far done with only LWD/WLL, but also making it possible to geosteer on fluid properties. Elemental analysis of cuttings, e.g. with XRF, with an ability well beyond the capabilities of the spectroscopy measurements possible earlier with LWD/WLL tools, is opening up improved ways to evaluate formations, especially of course where the traditional methods are falling short of requirements, such as in unconventional reservoirs. An overview and specific examples of these AML logs is given, from which it may be concluded that AML now ought to be considered as “first among its equals”.

  15. Die Last mit der Lust

    Directory of Open Access Journals (Sweden)

    Lutz Sauerteig

    2004-03-01

    Full Text Available Robert Jütte legt mit Lust ohne Last eine umfassende, allgemeinverständliche und spannend zu lesende Geschichte der Empfängnisverhütung von der Antike bis in die unmittelbare Gegenwart vor.

  16. Pulsed neutron logging - a modern approach to petroleum exploration

    International Nuclear Information System (INIS)

    Navalkar, M.P.

    1978-01-01

    As hydrocarbons have strikingly different properties for neutrons as compared with rocks, neutronic methods are useful to prepare logs of bore holes drilled for petroleum exploration. The earlier neutron logs were based on steady neutron sources, but the superior logs, namely, neutron life time log and neutron induced spectral log are based on pulsed neutron sources. The methods of obtaining these logs, their limitations and the field equipment required are described briefly. As the two logs are complementary, a plea has been made to develop field equipment which can obtain two logs in a single run. (M.G.B.)

  17. Use of activity logs to improve online collaboration

    Directory of Open Access Journals (Sweden)

    César Coll Salvador

    2018-02-01

    Full Text Available This article presents a review of works that center their interest in eLearning platforms and the data mining of participants’ activity. The studies in this research area generate information, through the analysis of such logs and data, that is provided to the students in real time to help them to collaborate and learn through collaboration on the platform. There are studies from different areas of study such as Learning Analytics, Educational Data Mining, Group Awareness Tools or Interaction Analysis Tools. The review takes a double perspective: i to analyze the data extracted from activity logs, their processing, the information generated and the ways to communicate it; and ii to explorer the model and the instruments used to assess how the information provided impact on online collaborative processes and/or the learning. The conclusions emphasize that the models of collaborative learning that justifies the selection of the data extracted from the activity logs, the processing, the information generated and provided to the students and the way of communicating it, are not explicitly stated. In addition, important biases are detected because of not considering the multidimensional nature of the collaborative learning processes. Also, few studies analyze the relations between students' uses of the information provided and the quality of their collaborative processes and learning results. The very few studies that do analyze such relation do not go into depth on the changes in group dynamics caused by information.

  18. Fracture diagnostics with tube wave reflection logs

    International Nuclear Information System (INIS)

    Medlin, W.L.

    1991-01-01

    This paper reports on the Tube Wave Reflection Log (TWRL) which is acoustic logging method which provides information about the height, location and conductivity of hydraulically induced fractures behind perforated casing. The TWRL tool consists of a transmitter and closely spaced receiver. The transmitter is driven with a short, low frequency tone burst to generate long wavelength tube waves which are little attenuated in unperforated casing. They are partially reflected when they pass perforated intervals communicating with a hydraulically induced fracture. The tool listens for such reflections for 0.1 seconds following each excitation burst. As the tool is moved uphole at logging speed, the transmitter is excited at each foot of depth. VDL displays of the TWRL records provide reflection traces whose projections define the uppermost and lower-most perforations communicating with the fracture. The strength of the reflections depends on the ease of fluid flow into the fracture and thus, is an indicator of fracture conductivity

  19. Smartphone log data in a qualitative perspective

    DEFF Research Database (Denmark)

    Ørmen, Jacob; Thorhauge, Anne Mette

    2015-01-01

    into studies of smartphones in everyday life. Through an illustrative study, we explore a more nuanced perspective on what can be considered “log data” and how these types of data can be collected and analysed. A qualitative approach to log data analysis offers researchers new opportunities to situate......Log data from smartphones have primarily been used in large-scale research designs to draw statistical inferences from hundreds or even thousands of participants. In this article, we argue that more qualitatively oriented designs can also benefit greatly from integrating these rich data sources...... serve as cues to instigate discussion and reflection as well as act as resources for contextualizing and organizing related empirical material. In the discussion, the advantages of a qualitative perspective for research designs are assessed in relation to issues of validity. Further perspectives...

  20. Financial feasibility of a log sort yard handling small-diameter logs: A preliminary study

    Science.gov (United States)

    Han-Sup Han; E. M. (Ted) Bilek; John (Rusty) Dramm; Dan Loeffler; Dave Calkin

    2011-01-01

    The value and use of the trees removed in fuel reduction thinning and restoration treatments could be enhanced if the wood were effectively evaluated and sorted for quality and highest value before delivery to the next manufacturing destination. This article summarizes a preliminary financial feasibility analysis of a log sort yard that would serve as a log market to...

  1. Geothermal well log interpretation midterm report

    Energy Technology Data Exchange (ETDEWEB)

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

    1979-02-01

    Reservoir types are defined according to fluid phase and temperature, lithology, geologic province, pore geometry, and salinity and fluid chemistry. Improvements are needed in lithology and porosity definition, fracture detection, and thermal evaluation for more accurate interpretation. Further efforts are directed toward improving diagnostic techniques for relating rock characteristics and log response, developing petrophysical models for geothermal systems, and developing thermal evaluation techniques. The Geothermal Well Log Interpretation study and report has concentrated only on hydrothermal geothermal reservoirs. Other geothermal reservoirs (hot dry rock, geopressured, etc.) are not considered.

  2. New portable neutron generator for well logging

    International Nuclear Information System (INIS)

    Chicanov, A.E.; Gromov, E. V.; Gulko, V. M.; Izmailov, A. V.

    1994-01-01

    The information about the design, investigation and testing of new well neutron generator for the pulse neutron logging (PNL) is given in this paper. The main physical characteristics of new PNL apparatus are: Neutron flux 2.10 sup 8 n/s ; Pulse frequency>=400 Hz; Diameter= 90 mm; Logging velocity >200 m/h; Number of probes = 2; Resource > 300 h. The generator were provided by gas-filled neutron accelerative tube named NTF-2. The perspective of application and optimization shown PNL apparatus are considered. (author)

  3. Analyzing Log Files using Data-Mining

    Directory of Open Access Journals (Sweden)

    Marius Mihut

    2008-01-01

    Full Text Available Information systems (i.e. servers, applications and communication devices create a large amount of monitoring data that are saved as log files. For analyzing them, a data-mining approach is helpful. This article presents the steps which are necessary for creating an ‘analyzing instrument’, based on an open source software called Waikato Environment for Knowledge Analysis (Weka [1]. For exemplification, a system log file created by a Windows-based operating system, is used as input file.

  4. Kaizen aplicado à logística

    OpenAIRE

    Santos, Ana Catarina Almeida

    2011-01-01

    O presente trabalho propõe alcançar um aumento de produtividade e consequente redução de custos e desperdícios ajudando o departamento logístico da Empresa Revigrés – Industria de Revestimentos de Grés, Lda, a tornar-se mais eficiente, através da aplicação da filosofia kaizen que propõe melhorias no desempenho por implementação de pequenas ações. O objetivo deste projeto é a melhoria do departamento logístico globalmente, para isso houve o recurso a pesquisas e levantamento ...

  5. Geophysical borehole logging test procedure: Final draft

    International Nuclear Information System (INIS)

    1986-09-01

    The purpose of geophysical borehole logging from the At-Depth Facility (ADF) is to provide information which will assist in characterizing the site geologic conditions and in classifying the engineering characteristics of the rock mass in the vicinity of the ADF. The direct goals of borehole logging include identification of lithologic units and their correlation from hole to hole, identification of fractured or otherwise porous or permeable zones, quantitative or semi-quantitative estimation of various formation properties, and evaluation of factors such as the borehole diameter and orientation. 11 figs., 4 tabs

  6. CS model coil experimental log book

    International Nuclear Information System (INIS)

    Nishijima, Gen; Sugimoto, Makoto; Nunoya, Yoshihiko; Wakabayashi, Hiroshi; Tsuji, Hiroshi

    2001-02-01

    Charging test of the ITER CS Model Coil which is the world's largest superconducting pulse coil and the CS Insert Coil had started at April 11, 2000 and had completed at August 18, 2000. In the campaign, total shot numbers were 356 and the size of the data file in the DAS (Data Acquisition System) was over 20 GB. This report is a database that consists of the log list and the log sheets of every shot. One can access the database, make a search, and browse results via Internet (http://1ogwww.naka.jaeri.go.jp). The database will be useful to quick search to choose necessary shots. (author)

  7. Perfil logístico de Colombia

    OpenAIRE

    Cardozo Maglioni, María Victoria; Lozano Suarez, María Goretty

    2012-01-01

    El presente documento ofrece un estudio del perfil logístico de Colombia con la finalidad de dar a conocer el estado de arte de las ciudades, puertos e infraestructura principal para facilitar la toma de decisiones de los empresarios. Para el desarrollo de este trabajo se determinaron a partir de un análisis competitivo del país; las principales ciudades y puertos; logrando establecer un inventario de maquinaria y equipo e infraestructura logística; enmarcados en retos ya establecidos en las ...

  8. Well logging instrumental and methodological research

    International Nuclear Information System (INIS)

    Andrassy, L.; Barath, I.; Dorko, R.

    1983-01-01

    This part of the Annual Report of the Roland Eoetvoes Geophysical Institute (ELGI) of Hungary for 1982, summarizes the well logging instrumental and methodological researches of ELGI. The theoretical neutron diffusion fluxes for black and brown coals of Hungarian mines were calculated. A coal probe was developed and tested in boreholes using computerized data processing and interpretation. An X-ray radiometric method was used for the determination of Cu and Fe contents of minerals. Researches in the field of magnetic susceptibility and induced polarization logging are also summarized. A rapid analyzer for bauxite mining and a photorecorder for petroleum industry were developed by ELGI. (D.Gy.)

  9. Influence of deforestation, logging, and fire on malaria in the Brazilian Amazon.

    Science.gov (United States)

    Hahn, Micah B; Gangnon, Ronald E; Barcellos, Christovam; Asner, Gregory P; Patz, Jonathan A

    2014-01-01

    Malaria is a significant public health threat in the Brazilian Amazon. Previous research has shown that deforestation creates breeding sites for the main malaria vector in Brazil, Anopheles darlingi, but the influence of selective logging, forest fires, and road construction on malaria risk has not been assessed. To understand these impacts, we constructed a negative binomial model of malaria counts at the municipality level controlling for human population and social and environmental risk factors. Both paved and unpaved roadways and fire zones in a municipality increased malaria risk. Within the timber production states where 90% of deforestation has occurred, compared with areas without selective logging, municipalities where 0-7% of the remaining forests were selectively logged had the highest malaria risk (1.72, 95% CI 1.18-2.51), and areas with higher rates of selective logging had the lowest risk (0.39, 95% CI 0.23-0.67). We show that roads, forest fires, and selective logging are previously unrecognized risk factors for malaria in the Brazilian Amazon and highlight the need for regulation and monitoring of sub-canopy forest disturbance.

  10. Influence of deforestation, logging, and fire on malaria in the Brazilian Amazon.

    Directory of Open Access Journals (Sweden)

    Micah B Hahn

    Full Text Available Malaria is a significant public health threat in the Brazilian Amazon. Previous research has shown that deforestation creates breeding sites for the main malaria vector in Brazil, Anopheles darlingi, but the influence of selective logging, forest fires, and road construction on malaria risk has not been assessed. To understand these impacts, we constructed a negative binomial model of malaria counts at the municipality level controlling for human population and social and environmental risk factors. Both paved and unpaved roadways and fire zones in a municipality increased malaria risk. Within the timber production states where 90% of deforestation has occurred, compared with areas without selective logging, municipalities where 0-7% of the remaining forests were selectively logged had the highest malaria risk (1.72, 95% CI 1.18-2.51, and areas with higher rates of selective logging had the lowest risk (0.39, 95% CI 0.23-0.67. We show that roads, forest fires, and selective logging are previously unrecognized risk factors for malaria in the Brazilian Amazon and highlight the need for regulation and monitoring of sub-canopy forest disturbance.

  11. Logging costs and cutting methods in young-growth ponderosa pine in California

    Science.gov (United States)

    Philip M. McDonald; William A. Atkinson; Dale O. Hall

    1969-01-01

    Mixed-conifer stands at the Challenge Experimental Forest, Calif., were cut to four specifications: seed-tree, group selection, single tree selection, and clearcut. Logging costs and production rates were compared and evaluated. Cutting method had little effect on felling or skidding production; felling ranged from 1,802 to 2,019 bd ft per hour, and skidding from 3,138...

  12. Spurious Additional Warming Reconstructed From Borehole Temperatures Corrected for the Effect of the Last Glacial Cycle

    Science.gov (United States)

    Šafanda, Jan

    2018-03-01

    Reconstructions of past ground surface temperature changes from temperature logs conducted in several hundred meter deep boreholes have proved to be a valuable independent source of information on climate variations over the last millennium. The reconstruction techniques have been evolving for more than two decades to extract optimally the climate signal of the last millennium contained in the temperature logs of different length performed in sites with different histories of the Last Glacial Cycle. This paper analyzes the method of the Last Glacial Cycle thermal effect removal from such borehole temperature profiles used by Beltrami et al. (2017, https://doi.org/10.1002/2016GL071317) in reconstructing the last 500 year history. I show that the reported results of additional warming in this period reconstructed from the corrected borehole data for North America are an artifact generated by the correction.

  13. Extracting useful knowledge from event logs

    DEFF Research Database (Denmark)

    Djenouri, Youcef; Belhadi, Asma; Fournier-Viger, Philippe

    2018-01-01

    Business process analysis is a key activity that aims at increasing the efficiency of business operations. In recent years, several data mining based methods have been designed for discovering interesting patterns in event logs. A popular type of methods consists of applying frequent itemset mini...

  14. Potential for shared log transport services

    Science.gov (United States)

    Tim McDonald; Steve Taylor; Jorge Valenzuela

    2001-01-01

    A simulation model of a log transport logistics network was developed. The model could be structured to either share truck capacity among a group of loggers, or to assign a fixed number of trucks to individual loggers. Another variation of the model allowed the use of a staging yard to set out loaded trailers and deliver them to destinations using dedicated shuttle...

  15. Identifying unstable sites on logging roads

    Science.gov (United States)

    R. M. Rice; J. Lewis

    1986-01-01

    Logging roads are an important source of forestry-related erosion. The amount of erosion on a forest road is determined by the interaction between how the road is constructed and maintained and the environment in which it is built. The roads in this study were constructed with large bulldozers, and most excavated material was sidecast. The roads studied were...

  16. Changes in the Logging Labor Force

    Science.gov (United States)

    Charles H. Wolf; Jean W. Nolley

    1977-01-01

    Employment in the logging industry dropped 28 percent between 1950 and 1970, while output of industrial roundwood increased 31 percent. Today's loggers are older, better educated, and more skilled. A large proportion are self-employed, many work less than a full year, and a substantial number have incomes below the poverty level. Mechanization of timber harvesting...

  17. Alaska midgrade logs: supply and offshore demand.

    Science.gov (United States)

    Donald F. Flora; Wendy J. McGinnis

    1989-01-01

    The outlook for shipments and prices of export logs from Alaska differs significantly by grade (quality class). For the majority lying in the middle of the value range, the trend of prices is projected to increase $200 per thousand board feet, or about 55 percent, by 2000. Shipments are expected to rise about 30 percent by 1995 and then subside about 10 percent. These...

  18. Analyzing Grid Log Data with Affinity Propagation

    NARCIS (Netherlands)

    Modena, G.; van Someren, M.W.; Ali, M; Bosse, T.; Hindriks, K.V.; Hoogendoorn, M.; Jonker, C.M; Treur, J.

    2013-01-01

    In this paper we present an unsupervised learning approach to detect meaningful job traffic patterns in Grid log data. Manual anomaly detection on modern Grid environments is troublesome given their increasing complexity, the distributed, dynamic topology of the network and heterogeneity of the jobs

  19. Exploration and grade control neutron logging

    International Nuclear Information System (INIS)

    Eisler, P.L.

    1982-01-01

    Techniques used in neutron logging in boreholes are discussed. They include the application of neutron probes to porosity measurements, to lithological determinations based on macroscopic cross-section measurements and measurements of the concentration of chemical constituents in rocks and ores

  20. Explorations in statistics: the log transformation.

    Science.gov (United States)

    Curran-Everett, Douglas

    2018-06-01

    Learning about statistics is a lot like learning about science: the learning is more meaningful if you can actively explore. This thirteenth installment of Explorations in Statistics explores the log transformation, an established technique that rescales the actual observations from an experiment so that the assumptions of some statistical analysis are better met. A general assumption in statistics is that the variability of some response Y is homogeneous across groups or across some predictor variable X. If the variability-the standard deviation-varies in rough proportion to the mean value of Y, a log transformation can equalize the standard deviations. Moreover, if the actual observations from an experiment conform to a skewed distribution, then a log transformation can make the theoretical distribution of the sample mean more consistent with a normal distribution. This is important: the results of a one-sample t test are meaningful only if the theoretical distribution of the sample mean is roughly normal. If we log-transform our observations, then we want to confirm the transformation was useful. We can do this if we use the Box-Cox method, if we bootstrap the sample mean and the statistic t itself, and if we assess the residual plots from the statistical model of the actual and transformed sample observations.

  1. Apache Flume distributed log collection for Hadoop

    CERN Document Server

    D'Souza, Subas

    2013-01-01

    A starter guide that covers Apache Flume in detail.Apache Flume: Distributed Log Collection for Hadoop is intended for people who are responsible for moving datasets into Hadoop in a timely and reliable manner like software engineers, database administrators, and data warehouse administrators

  2. 47 CFR 80.409 - Station logs.

    Science.gov (United States)

    2010-10-01

    ... primary office or available to the Commission via secured access to the licensee's Internet web site. Logs..., together with the time of such observation or occurrence and the position of the ship or other mobile unit... devices which do not have integral navigation receivers, including: VHF DSC, MF DSC, satellite EPIRB and...

  3. Geophysical logging for mineral exploration and development

    International Nuclear Information System (INIS)

    Plouffe, R.D.

    1981-01-01

    It is possible to retrieve from small-diameter holes geophysical data for qualitative interpretation in exploration and quantitative interpretation in the development of orebodies. The primary objectives in the exploration stage are to identify where, within a hole, economic minerals are, and to help in lithological interpretations. Other aspects, which are more quantitative, are the interpretation of downhole logs for parameters which can be used in surface geophysical methods (i.e. density for gravity surveys, acoustic velocities for seismic surveys, and magnetic susceptibility for airborne and ground magnetic surveys). Recent advances in equipment design, portability and durability have made downhole logging in exploration more inexpensive and reliable. This new equipment is being used to generate very precise quantitative results. This is especially true on uranium development projects. The interpretation of gamma logs for eU 3 O 8 values has finally become precise enough that they have begun to replace chemical values in reserve calculations. Another part of development data is density and equilibrium information, which, with today's technology, is being derived from downhole probing. In the years to come, the trends for many metals are toward neutron activation techniques, or in-situ assaying, and the use of multiple logs for better lithological and physical rock property determinations. (auth)

  4. Information needs for increasing log transport efficiency

    Science.gov (United States)

    Timothy P. McDonald; Steven E. Taylor; Robert B. Rummer; Jorge Valenzuela

    2001-01-01

    Three methods of dispatching trucks to loggers were tested using a log transport simulation model: random allocation, fixed assignment of trucks to loggers, and dispatch based on knowledge of the current status of trucks and loggers within the system. This 'informed' dispatch algorithm attempted to minimize the difference in time between when a logger would...

  5. Root cause analysis with enriched process logs

    NARCIS (Netherlands)

    Suriadi, S.; Ouyang, C.; Aalst, van der W.M.P.; Hofstede, ter A.H.M.; La Rosa, M.; Soffer, P.

    2013-01-01

    n the field of process mining, the use of event logs for the purpose of root cause analysis is increasingly studied. In such an analysis, the availability of attributes/features that may explain the root cause of some phenomena is crucial. Currently, the process of obtaining these attributes from

  6. Mining process performance from event logs

    NARCIS (Netherlands)

    Adriansyah, A.; Buijs, J.C.A.M.; La Rosa, M.; Soffer, P.

    2013-01-01

    In systems where process executions are not strictly enforced by a predefined process model, obtaining reliable performance information is not trivial. In this paper, we analyzed an event log of a real-life process, taken from a Dutch financial institute, using process mining techniques. In

  7. Lianas and logging in West Africa

    NARCIS (Netherlands)

    Parren, M.P.E.

    2003-01-01

    The role of lianas in relation to logging activities is analysed in a lowland moist forest in Cameroon. Lianas are an abundant, diverse, and conspicuous growth form in nearly all tropical forests. Lianas are mostly seen as a nuisance by foresters. Cutting of liana stems is an important operation in

  8. Attraction of Tomicus yunnanensis (Coleoptera: Scolytidae to Yunnan Pine Logs with and without Periderm or Phloem: An Effective Monitoring Bait

    Directory of Open Access Journals (Sweden)

    Rong Chun Lu

    2012-01-01

    Full Text Available The Yunnan pine shoot beetle, Tomicus yunnanensis Kirkendall and Faccoli (Coleoptera: Scolytinae is an important pest of Yunnan pine (Pinus yunnanensis Franch in China. Experiments with host log baits were done to develop a pest monitoring system using host tree kairomone. Five Yunnan pine logs (each 10–15 cm diam. × 30-cm long in a trap-log bundle were treated by peeling periderm (outer bark off to expose the phloem, and half of each log was covered with sticky adhesive to capture any attracted adult beetles. Significantly, more beetles were attracted and caught on the periderm-peeled logs (ca 30 beetles/m2 log surface/day than on untreated control logs with adhesive (ca 2.5/m2/day. No significant differences were observed between catches on logs taken from lower or upper halves of Yunnan pines. T. yunnanensis flies mostly during the afternoon according to trap catches throughout the day. Attraction to the periderm-peeled logs decreased considerably when they were peeled further to remove the phloem, indicating phloem volatiles play a role in selection of the host by the beetle. The readily-available log baits appear useful for monitoring pine shoot beetle populations in integrated pest management programs.

  9. EFFECT OF THINNING AND FERTILIZATION ON Eucalyptus grandis Hill ex-Maiden PITH DISPLACEMENT AND LOG END SPLITTlNG

    Directory of Open Access Journals (Sweden)

    Israel Luiz de Lima

    2007-06-01

    Full Text Available The aim of this study was to analyse the influence of thinning and fertilization on some log properties which influence sawn wood yield in a 21 year-old grown Eucalyptus grandis stand. Three selective thinning intensities (37, 50 and 75%, presence or absence of fertilizers on the beginning of the thinning, two diameter classes and two logs taken from two different vertical positions were taken as the study factors. The influence of the factors and their combination on tree growth stresses were indirectly evaluate through log end splitting and pith displacement in relation to its normal central position. Thinning, fertilization, diameter class and log position on the tree height did not have significant effect on pith displacement. The logs from fertilized plots presented higher log end splitting index than others.

  10. Target recognition of log-polar ladar range images using moment invariants

    Science.gov (United States)

    Xia, Wenze; Han, Shaokun; Cao, Jie; Yu, Haoyong

    2017-01-01

    The ladar range image has received considerable attentions in the automatic target recognition field. However, previous research does not cover target recognition using log-polar ladar range images. Therefore, we construct a target recognition system based on log-polar ladar range images in this paper. In this system combined moment invariants and backpropagation neural network are selected as shape descriptor and shape classifier, respectively. In order to fully analyze the effect of log-polar sampling pattern on recognition result, several comparative experiments based on simulated and real range images are carried out. Eventually, several important conclusions are drawn: (i) if combined moments are computed directly by log-polar range images, translation, rotation and scaling invariant properties of combined moments will be invalid (ii) when object is located in the center of field of view, recognition rate of log-polar range images is less sensitive to the changing of field of view (iii) as object position changes from center to edge of field of view, recognition performance of log-polar range images will decline dramatically (iv) log-polar range images has a better noise robustness than Cartesian range images. Finally, we give a suggestion that it is better to divide field of view into recognition area and searching area in the real application.

  11. Requirements-Driven Log Analysis Extended Abstract

    Science.gov (United States)

    Havelund, Klaus

    2012-01-01

    Imagine that you are tasked to help a project improve their testing effort. In a realistic scenario it will quickly become clear, that having an impact is diffcult. First of all, it will likely be a challenge to suggest an alternative approach which is significantly more automated and/or more effective than current practice. The reality is that an average software system has a complex input/output behavior. An automated testing approach will have to auto-generate test cases, each being a pair (i; o) consisting of a test input i and an oracle o. The test input i has to be somewhat meaningful, and the oracle o can be very complicated to compute. Second, even in case where some testing technology has been developed that might improve current practice, it is then likely difficult to completely change the current behavior of the testing team unless the technique is obviously superior and does everything already done by existing technology. So is there an easier way to incorporate formal methods-based approaches than the full edged test revolution? Fortunately the answer is affirmative. A relatively simple approach is to benefit from possibly already existing logging infrastructure, which after all is part of most systems put in production. A log is a sequence of events, generated by special log recording statements, most often manually inserted in the code by the programmers. An event can be considered as a data record: a mapping from field names to values. We can analyze such a log using formal methods, for example checking it against a formal specification. This separates running the system for analyzing its behavior. It is not meant as an alternative to testing since it does not address the important in- put generation problem. However, it offers a solution which testing teams might accept since it has low impact on the existing process. A single person might be assigned to perform such log analysis, compared to the entire testing team changing behavior.

  12. Anomalous self potential (sp) log signatures observed in a water ...

    African Journals Online (AJOL)

    Geophysical logging was done after drilling had been completed in a water well at Okwudor, South Eastern Nigeria. Three electric logs were run viz: Self Potential (SP), Resistivity N16″ and N64″ logs. An anomaly was observed in the SP log. The SP results from this well show some deviation from the standard norm.

  13. Using Web Server Logs in Evaluating Instructional Web Sites.

    Science.gov (United States)

    Ingram, Albert L.

    2000-01-01

    Web server logs contain a great deal of information about who uses a Web site and how they use it. This article discusses the analysis of Web logs for instructional Web sites; reviews the data stored in most Web server logs; demonstrates what further information can be gleaned from the logs; and discusses analyzing that information for the…

  14. Stress wave sorting of red maple logs for structural quality

    Science.gov (United States)

    Xiping Wang; Robert J. Ross; David W. Green; Brian Brashaw; Karl Englund; Michael Wolcott

    2004-01-01

    Existing log grading procedures in the United States make only visual assessments of log quality. These procedures do not incorporate estimates of the modulus of elasticity (MOE) of logs. It is questionable whether the visual grading procedures currently used for logs adequately assess the potential quality of structural products manufactured from them, especially...

  15. Tradeoffs and interdependence in the Alaska cant and log markets.

    Science.gov (United States)

    Donald Flora; Una Woller; Michael. Neergaard

    1990-01-01

    During the 1980s, log exports from Alaska have risen while cant (lumber) exports have declined. Eight explanations for the difference between cant and log market behavior are explored. It seems that declining demand for wood products in Japan and a surge of private-sector log harvests in Alaska are enough to account for the apparent substitution of logs for cants. It...

  16. Performance of sampling methods to estimate log characteristics for wildlife.

    Science.gov (United States)

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

    2004-01-01

    Accurate estimation of the characteristics of log resources, or coarse woody debris (CWD), is critical to effective management of wildlife and other forest resources. Despite the importance of logs as wildlife habitat, methods for sampling logs have traditionally focused on silvicultural and fire applications. These applications have emphasized estimates of log volume...

  17. Advanced of X-ray fluorescence logging technique in China

    International Nuclear Information System (INIS)

    Zhou Sichun; Ge Liangquan; Lai Wanchang; Yang Qiang

    2010-01-01

    The paper discuses principle of X-ray fluorescence logging, and introduces advanced of X-ray fluorescence logging technique in China. By 2009, third generation XRF logging instrument has been developed in China, and good logging result has been obtained in Lala copper mine. (authors)

  18. Trouble Don't Last

    Science.gov (United States)

    Pearsall, Shelley

    2004-01-01

    Even as a child, Pearsall questioned social injustice and prejudice. In her own community in Ohio and, as she grew, all over the world, she saw social inequities she could neither understand nor accept. Her novel "Trouble Don't Last," takes place during the era of the Underground Railroad. The chapter included here pulls us in…

  19. Raising the last LEP dipole

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    The last of the 3280 dipole magnets from the Large Electron-Positron (LEP) collider is seen on its journey to the surface on 12 February 2002. The LEP era, which began at CERN in 1989 and ended 2000, comes to an end.

  20. Optimized Design of Spacing in Pulsed Neutron Gamma Density Logging While Drilling

    Directory of Open Access Journals (Sweden)

    ZHANG Feng;HAN Zhong-yue;WU He;HAN Fei

    2016-10-01

    Full Text Available Radioactive source, used in traditional density logging, has great impact on the environment, while the pulsed neutron source applied in the logging tool is more safety and greener. In our country, the pulsed neutron-gamma density logging technology is still in the stage of development. Optimizing the parameters of neutron-gamma density instrument is essential to improve the measuring accuracy. This paper mainly studied the effects of spacing to typical neutron-gamma density logging tool which included one D-T neutron generator and two gamma scintillation detectors. The optimization of spacing were based on measuring sensitivity and counting statistic. The short spacing from 25 to 35 cm and long spacing from 60 to 65 cm were selected as the optimal position for near and far detector respectively. The result can provide theoretical support for design and manufacture of the instrument.

  1. Limitations and developing directions of pulsed neutron logging

    International Nuclear Information System (INIS)

    Wu Wensheng; Xiao Lizhi

    2007-01-01

    The paper explains briefly the principle of pulsed neutron logging method, summarizes the system and uses of the method in petroleum logging. The paper points out the limitations of pulsed neutron logging such as low precise measurements, low logging speed, plenty of influence factors, low vertical resolution, bad adaptability, difficult logging interpretation and so on, and expounds its developing directions in hardware, software, method and principle. (authors)

  2. Life cycle performances of log wood applied for soil bioengineering constructions

    Science.gov (United States)

    Kalny, Gerda; Strauss-Sieberth, Alexandra; Strauss, Alfred; Rauch, Hans Peter

    2016-04-01

    Nowadays there is a high demand on engineering solutions considering not only technical aspects but also ecological and aesthetic values. Soil bioengineering is a construction technique that uses biological components for hydraulic and civil engineering solutions. Soil bioengineering solutions are based on the application of living plants and other auxiliary materials including among others log wood. This kind of construction material supports the soil bioengineering system as long as the plants as living construction material overtake the stability function. Therefore it is important to know about the durability and the degradation process of the wooden logs to retain the integral performance of a soil bio engineering system. These aspects will be considered within the framework of the interdisciplinary research project „ELWIRA Plants, wood, steel and concrete - life cycle performances as construction materials". Therefore field investigations on soil bioengineering construction material, specifically European Larch wood logs, of different soil bioengineering structures at the river Wien have been conducted. The drilling resistance as a parameter for particular material characteristics of selected logs was measured and analysed. The drilling resistance was measured with a Rinntech Resistograph instrument at different positions of the wooden logs, all surrounded with three different backfills: Fully surrounded with air, with earth contact on one side and near the water surface in wet-dry conditions. The age of the used logs ranges from one year old up to 20 year old. Results show progress of the drilling resistance throughout the whole cross section as an indicator to assess soil bioengineering construction material. Logs surrounded by air showed a higher drilling resistance than logs with earth contact and the ones exposed to wet-dry conditions. Hence the functional capability of wooden logs were analysed and discussed in terms of different levels of degradation

  3. Reduced-impact logging and biodiversity conservation: a case study from Borneo.

    Science.gov (United States)

    Edwards, David P; Woodcock, Paul; Edwards, Felicity A; Larsen, Trond H; Hsu, Wayne W; Benedick, Suzan; Wilcove, David S

    2012-03-01

    A key driver of rain forest degradation is rampant commercial logging. Reduced-impact logging (RIL) techniques dramatically reduce residual damage to vegetation and soils, and they enhance the long-term economic viability of timber operations when compared to conventionally managed logging enterprises. Consequently, the application of RIL is increasing across the tropics, yet our knowledge of the potential for RIL also to reduce the negative impacts of logging on biodiversity is minimal. We compare the impacts of RIL on birds, leaf-litter ants, and dung beetles during a second logging rotation in Sabah, Borneo, with the impacts of conventional logging (CL) as well as with primary (unlogged) forest. Our study took place 1-8 years after the cessation of logging. The species richness and composition of RIL vs. CL forests were very similar for each taxonomic group. Both RIL and CL differed significantly from unlogged forests in terms of bird and ant species composition (although both retained a large number of the species found in unlogged forests), whereas the composition of dung beetle communities did not differ significantly among forest types. Our results show little difference in biodiversity between RIL and CL over the short-term. However, biodiversity benefits from RIL may accrue over longer time periods after the cessation of logging. We highlight a severe lack of studies investigating this possibility. Moreover, if RIL increases the economic value of selectively logged forests (e.g., via REDD+, a United Nations program: Reducing Emissions from Deforestation and Forest Degradation in Developing Countries), it could help prevent them from being converted to agricultural plantations, which results in a tremendous loss of biodiversity.

  4. Mapping soil particle-size fractions: A comparison of compositional kriging and log-ratio kriging

    Science.gov (United States)

    Wang, Zong; Shi, Wenjiao

    2017-03-01

    Soil particle-size fractions (psf) as basic physical variables need to be accurately predicted for regional hydrological, ecological, geological, agricultural and environmental studies frequently. Some methods had been proposed to interpolate the spatial distributions of soil psf, but the performance of compositional kriging and different log-ratio kriging methods is still unclear. Four log-ratio transformations, including additive log-ratio (alr), centered log-ratio (clr), isometric log-ratio (ilr), and symmetry log-ratio (slr), combined with ordinary kriging (log-ratio kriging: alr_OK, clr_OK, ilr_OK and slr_OK) were selected to be compared with compositional kriging (CK) for the spatial prediction of soil psf in Tianlaochi of Heihe River Basin, China. Root mean squared error (RMSE), Aitchison's distance (AD), standardized residual sum of squares (STRESS) and right ratio of the predicted soil texture types (RR) were chosen to evaluate the accuracy for different interpolators. The results showed that CK had a better accuracy than the four log-ratio kriging methods. The RMSE (sand, 9.27%; silt, 7.67%; clay, 4.17%), AD (0.45), STRESS (0.60) of CK were the lowest and the RR (58.65%) was the highest in the five interpolators. The clr_OK achieved relatively better performance than the other log-ratio kriging methods. In addition, CK presented reasonable and smooth transition on mapping soil psf according to the environmental factors. The study gives insights for mapping soil psf accurately by comparing different methods for compositional data interpolation. Further researches of methods combined with ancillary variables are needed to be implemented to improve the interpolation performance.

  5. Theoretical and Numerical Study of Seismoelectric Logs for Logging While Drilling (LWD

    Directory of Open Access Journals (Sweden)

    Sun Xiang-Yang

    2017-01-01

    Full Text Available When the acoustic field propagates in the porous medium, the electromagnetic wave can be induced by the seismoelectric effects which can be used in the logging. This paper studies the seismoelectric wave field and deduces the formulations of the acoustic and electromagnetic field of the liquid in the well, and gives the acoustic and electromagnetic boundary conditions between the driller collar and the log liquid, when the driller collar is added. We also do the numerical simulation of the seismoelectric wave field excited by monopole source, study the velocity dispersion characteristics of the acoustic and electromagnetic field, and investigate the detective depth of the seismoelectric logs. Through the simulation we know the seismoelectric logs can avoid the interference of drill collar wave. This paper also provides theoretical guidance for the design of receiving antenna.

  6. Comparative analysis of nuclear magnetic resonance well logging and nuclear magnetic resonance mud logging

    International Nuclear Information System (INIS)

    Yuan Zugui

    2008-01-01

    The hydrogen atoms in oil and water are able to resonate and generate signals in the magnetic field, which is used by the NMR (nuclear magnetic resonance) technology in petroleum engineering to research and evaluate rock characteristics. NMR well logging was used to measure the physical property parameters of the strata in well bore, whereas NMR mud logging was used to analyze (while drilling) the physical property parameters of cores, cuttings and sidewall coring samples on surface (drilling site). Based on the comparative analysis of the porosity and permeability parameters obtained by NMR well logging and those from analysis of the cores, cuttings and sidewall coring samples by NMR mud logging in the same depth of 13 wells, these two methods are of certain difference, but their integral tendency is relatively good. (authors)

  7. Lectures on Fermat's last theorem

    International Nuclear Information System (INIS)

    Sury, B.

    1993-09-01

    The report presents the main ideas involved in the approach towards the so-called Fermat's last theorem (FLT). The discussion leads to the point where recent work of A. Wiles starts and his work is not discussed. After a short history of the FLT and of the present approach, are discussed the elliptic curves and the modular forms with their relations, the Taniyama-Shimura-Well conjecture and the FLT

  8. Preparing for the last fling

    Directory of Open Access Journals (Sweden)

    Odelia Muller

    1981-09-01

    Full Text Available Re t i r e m e n t — the last flin g — seems to be a phenomenon peculiar to the present age and culture which is geared to suit the convenience of the social system rather than the needs of the individual. In the Western world alone 291 million people are over the age of 60 and every day 14 thousand individuals, irrespective of their potential contribution to industry, commerce and state, are scheduled to retire.

  9. CS model coil experimental log book

    Energy Technology Data Exchange (ETDEWEB)

    Nishijima, Gen; Sugimoto, Makoto; Nunoya, Yoshihiko; Wakabayashi, Hiroshi; Tsuji, Hiroshi [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    2001-02-01

    Charging test of the ITER CS Model Coil which is the world's largest superconducting pulse coil and the CS Insert Coil had started at April 11, 2000 and had completed at August 18, 2000. In the campaign, total shot numbers were 356 and the size of the data file in the DAS (Data Acquisition System) was over 20 GB. This report is a database that consists of the log list and the log sheets of every shot. One can access the database, make a search, and browse results via Internet (http://1ogwww.naka.jaeri.go.jp). The database will be useful to quick search to choose necessary shots. (author)

  10. High resolution gamma spectroscopy well logging system

    International Nuclear Information System (INIS)

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

    1997-01-01

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

  11. Well logging system with linearity control

    International Nuclear Information System (INIS)

    Jones, J.M.

    1973-01-01

    Apparatus is described for controlling the gain of a nuclear well logging system comprising: (1) means for measuring the energy spectrum of gamma rays produced by earth formation materials surrounding a well borehole; (2) means for measuring the number of counts of a gamma rays having an energy falling within each of at least two predetermined energy band portions of the gamma ray energy spectrum; (3) means for generating a signal proportional to the ratio of the gamma ray counts and for comparing the ratio signal with at least one constant ratio calibration signal; (4) means for generating an error signal representative of the difference of the ratio signal and the constant ratio calibration signal; and (5) means for using the error signal to control the linearity of the well logging system. (author)

  12. Assessment of radiation safety in well logging

    International Nuclear Information System (INIS)

    Alles, A.; Pérez, Y.; Duménigo, C.

    2015-01-01

    Radiation safety assessments required by current regulations are a means to verify compliance with the requirements. Different methods have been used for this purpose. In the paper the results of applying the method of risk matrices, applied for the first time in the practice of well logging are exposed. For each initiating event frequency of occurrence, the severity of its consequences and the probability of failure of the barriers identified were evaluated. Starting from these assumptions, the risk associated is determined for each of the identified accident sequences, using for this the SEVRRA code 'Risk Assessment System', originally designed for use in radiotherapy. As an result sequences increased risk associated with the practice of well logging were identified, which is the starting point for the further implementation of a coherent program of dose optimization in practice. [es

  13. No chiral truncation of quantum log gravity?

    Science.gov (United States)

    Andrade, Tomás; Marolf, Donald

    2010-03-01

    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.

  14. Modelo de custos logísticos

    Directory of Open Access Journals (Sweden)

    José Vanderlei Silva Borba

    2010-05-01

    Full Text Available Em contexto de globalização, a distância física entre produtores de bens e de serviços e consumidores deixa de ser relevante. Isso determina que o gerenciamento de custos logísticos venha agregar valor relevante aos produtos comercializados, pois procura identificar e determinar a eficácia dos recursos consumidos internamente pela empresa e, externamente, procura fazer a análise da cadeia de valor. Nessa perspectiva, a definição das variáveis de custos está além de seus muros. Este trabalho propõe um modelo de apuração de custos logísticos, que atenda, simultaneamente, os custos de suprimentos e os custos de distribuição, com impactos sobre o processo de tomada de decisão.

  15. Development of a digital log ratemeter

    International Nuclear Information System (INIS)

    Domienikan, Claudio; Brito, Andreia; Toledo, Fabio de; Zahn, Guilherme S.

    2011-01-01

    A compact log ratemeter that measures and displays an average count rate through a microcomputer is presented. This ratemeter was developed to be used to monitor a laboratory of production of radioactive samples and also for teaching purposes. The main features are log measurement range from .1 to 1.000 counts/sec and adjustable level alarm. The electronic circuit uses a Geiger tube LND7224, and the processed signal is applied to a National Instruments Multifunction I/O USB-6008 connected to a PC through USB input. A program developed in LabView allows storage of data and real-time observation of the rate of radiation evolution. This ratemeter was designed and constructed in the IPEN-CNEN/SP. (author)

  16. Glass scintillator pair for compensation neutron logging

    International Nuclear Information System (INIS)

    Ji Changsong; Li Xuezhi; Yiu Guangduo

    1985-01-01

    Glass scintillator pair types ST 1604 and ST 1605 for compensation of neutron logging is developed. The neutron sensitive material used is multistick lithium glass scintillators 3 and 4 mm in diameter respectively. Thermoneutron detection efficiencies are 50-60% and 100% respectively. The detection efficiency for 60 Co γ ray is lower than 0.3%. The type ST 1604 and ST 1605 may also be used as high sensitive neutron detectors in an intensive γ ray field

  17. Log Gaussian Cox processes on the sphere

    DEFF Research Database (Denmark)

    Pacheco, Francisco Andrés Cuevas; Møller, Jesper

    We define and study the existence of log Gaussian Cox processes (LGCPs) for the description of inhomogeneous and aggregated/clustered point patterns on the d-dimensional sphere, with d = 2 of primary interest. Useful theoretical properties of LGCPs are studied and applied for the description of sky...... positions of galaxies, in comparison with previous analysis using a Thomas process. We focus on simple estimation procedures and model checking based on functional summary statistics and the global envelope test....

  18. Log-Concavity Properties of Minkowski Valuations

    OpenAIRE

    Berg, Astrid; Parapatits, Lukas; Schuster, Franz E.; Weberndorfer, Manuel

    2014-01-01

    New Orlicz Brunn-Minkowski inequalities are established for rigid motion compatible Minkowski valuations of arbitrary degree. These extend classical log-concavity properties of intrinsic volumes and generalize seminal results of Lutwak and others. Two different approaches which refine previously employed techniques are explored. It is shown that both lead to the same class of Minkowski valuations for which these inequalities hold. An appendix by Semyon Alesker contains the proof of a new clas...

  19. Methods for calibrating radioactivity well logging tools

    International Nuclear Information System (INIS)

    Waggoner, J.A.; Turcotte, R.E.; Hunt-Grubbe, R.H.

    1981-01-01

    Field-calibrating of well-logging tools is achieved by means of a sleeve, which has radioactive material distributed therein, and which envelopes the portion of the tool housing containing the detector. Accurate calibration can be performed and the source can be made considerably weaker than those now in use as it can be brought very close to the detector thus lessening errors. (U.K.)

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

    Science.gov (United States)

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

    2012-01-01

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

  1. Estimation of the non records logs from existing logs using artificial neural networks

    Directory of Open Access Journals (Sweden)

    Mehdi Mohammad Salehi

    2017-12-01

    Full Text Available Finding the information of the hydrocarbon reservoirs from well logs is one of the main objectives of the engineers. But, missing the log records (due to many reasons such as broken instruments, unsuitable borehole and etc. is a major challenge to achieve it. Prediction of the density and resistivity logs (Rt, DT and LLS from the conventional wire-line logs in one of the Iranian southwest oil fields is the main purpose of this study. Multilayer neural network was applied to develop an intelligent predictive model for prediction of the logs. A total of 3000 data sets from 3 wells (A, B and C of the studied field were used. Among them, the data of A, B and C wells were used to constructing and testing the model, respectively. To evaluate the performance of the model, the mean square error (MSE and correlation coefficient (R2 in the test data were calculated. A comparison between the MSE of the proposed model and recently intelligent models shows that the proposed model is more accurate than others. Acceptable accuracy and using conventional well logging data are the highlight advantages of the proposed intelligent model.

  2. Chiral gravity, log gravity, and extremal CFT

    International Nuclear Information System (INIS)

    Maloney, Alexander; Song Wei; Strominger, Andrew

    2010-01-01

    We show that the linearization of all exact solutions of classical chiral gravity around the AdS 3 vacuum have positive energy. Nonchiral 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 conformal field theories (CFT). Moreover we show that log gravity contains chiral gravity within it as a decoupled charge superselection sector. We formally 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.

  3. Gerencia logística y global

    Directory of Open Access Journals (Sweden)

    Pablo Cesar Ocampo Vélez

    2009-04-01

    Full Text Available La logística es una filosofía que se encarga de aplicar las buenas pá¡cticas en los macroprocesos, procesos, procedimientos, tareas y productos dentro de una organización, con el fin de satisfacer las necesidades del cliente, quien es la razón de ser de la empresa. Existen entes internacionales que velan porque las compañias en todo el mundo utilicen y difundan las diferentes disciplinas logísticas en toda la red de valor y tengan un mismo enfoque estratégico.El objetivo de este artículo es explicar la existencia de procesos y macroprocesos de clase mundial en la logística, gracias a los cuales hay una gran oportunidad de mejora para los empresarios colombianos, con el fin de reestructurar los procesos estratégicos, tácticos y operacionales de cada Unidad de Negocio, para que sean organizaciones más competitivas, que puedan enfrentar los tratados de libre comercio, brindando mayor sostenibilidad y óptimo nivel de servicio.

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

    Science.gov (United States)

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

    2010-12-01

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

  5. Rapid estimation of aquifer salinity structure from oil and gas geophysical logs

    Science.gov (United States)

    Shimabukuro, D.; Stephens, M.; Ducart, A.; Skinner, S. M.

    2016-12-01

    We describe a workflow for creating aquifer salinity maps using Archie's equation for areas that have geophysical data from oil and gas wells. We apply this method in California, where geophysical logs are available in raster format from the Division of Oil, Gas, and Geothermal Resource (DOGGR) online archive. This method should be applicable to any region where geophysical logs are readily available. Much of the work is controlled by computer code, allowing salinity estimates for new areas to be rapidly generated. For a region of interest, the DOGGR online database is scraped for wells that were logged with multi-tool suites, such as the Platform Express or Triple Combination Logging Tools. Then, well construction metadata, such as measured depth, spud date, and well orientation, is attached. The resultant local database allows a weighted criteria selection of wells that are most likely to have the shallow resistivity, deep resistivity, and density porosity measurements necessary to calculate salinity over the longest depth interval. The algorithm can be adjusted for geophysical log availability for older well fields and density of sampling. Once priority wells are identified, a student researcher team uses Neuralog software to digitize the raster geophysical logs. Total dissolved solid (TDS) concentration is then calculated in clean, wet sand intervals using the resistivity-porosity method, a modified form of Archie's equation. These sand intervals are automatically selected using a combination of spontaneous potential and the difference in shallow resistivity and deep resistivity measurements. Gamma ray logs are not used because arkosic sands common in California make it difficult to distinguish sand and shale. Computer calculation allows easy adjustment of Archie's parameters. The result is a semi-continuous TDS profile for the wells of interest. These profiles are combined and contoured using standard 3-d visualization software to yield preliminary salinity

  6. Estimating forest biomass and identifying low-intensity logging areas using airborne scanning lidar in Antimary State Forest, Acre State, Western Brazilian Amazon

    Science.gov (United States)

    Marcus V.N. d' Oliveira; Stephen E. Reutebuch; Robert J. McGaughey; Hans-Erik. Andersen

    2012-01-01

    The objectives of this study were to estimate above ground forest biomass and identify areas disturbed by selective logging in a 1000 ha Brazilian tropical forest in the Antimary State Forest using airborne lidar data. The study area consisted of three management units, two of which were unlogged, while the third unit was selectively logged at a low intensity. A...

  7. Looking for Improvement in Last Planner System: Defining Selection Criteria

    DEFF Research Database (Denmark)

    Lindhard, Søren; Wandahl, Søren

    2013-01-01

    criteria was carried out. Six flows are identified as relevant: workforce, material, and machinery which comprise the needed resources and safety, climate conditions, and space which affect the pace of the work. Because of the importance to progress in the workflow, and the on-schedule completeness...

  8. A history of nuclear well logging in the oil industry

    International Nuclear Information System (INIS)

    Tittle, C.W.

    1989-01-01

    Spurred by an interest in logging through steel casing γ-ray logging began in the late 1930s followed soon by neutron logging for porosity. These were the first two nuclear well logs. Gamma-gamma density logging was developed during the 1950s. Pulsed neutron lifetime logging appeared in the 1960s; the slim tools came in the early 1970s. Developments since then have included dual detector devices of several types which offered improved measurements or interpretation, γ-ray spectrometry logging (natural and neutron-induced) which identifies certain chemical elements, induced radioactivity logging, and the photoelectric absorption log, which, combined with the density log in a single tool, is known as litho-density logging. A combination of several γ-ray spectrometers in one tool, designed to determine 10 formation elements, was recently introduced, and a new neutron porosity tool measuring epithermal neutron die-away time has been developed. Digital transmission of logging data was a step forward in about 1975. Also, log interpretation techniques have greatly expanded since the advent of digital computers, and the microcomputer has had a distinct impact. It is now practical and economical to do iterative analysis on a suite of logs to obtain an optimum overall interpretation. (author)

  9. Unification of acoustic drillhole logging data

    International Nuclear Information System (INIS)

    Oehman, I.; Palmen, J.; Heikkinen, E.

    2009-04-01

    Posiva Oy prepares for disposal of spent nuclear fuel in bedrock in Olkiluoto, Eurajoki. This is in accordance of the application filed in 1999, the Decision-in-Principle of the State Council in 2000, and ratification by the Parliament in 2001. The site characterization at Olkiluoto has included comprehensive geological, hydrological, geochemical and geophysical investigations airborne, on ground and in drillholes since 1988. One of key techniques in geophysical drillhole surveys has been acoustic full waveform logging, which has been implemented since 1994. Various tools have been used in acquisition of acoustic data and several processing techniques have been applied. The logging work and processing to P and S wave velocities has been previously carried out on single drillhole basis. Comparisons to actual values and levels have not been made, and the results have not been calibrated. Therefore results for different drillholes have not been comparable. Resolution of the P and S wave velocity has been rather coarse, and depth correlation to the core data has been on tentative level. As the investigation data has been accumulating, it has become possible to correlate the results to geological and laboratory control data and to calibrate the results of separate measurement campaigns and different drillholes together onto same reference level and resolution. The presented technique has been applied for drillhole OL-KR29 onwards and has set the processing standard, settings and reference levels for later surveys. This approach will further assist the application of the method for mapping and numerical description of lithology variation and possible effect of alteration and deformation on it. Further on, the P and S wave velocity data together with density can be used in computing of dynamic in situ rock mechanical parameters, and possibly in correlating rock strength laboratory data to P and S wave velocity logging data. The acoustic logging data from drillholes OL-KR1

  10. Challenges and Opportunities in ‘Last Mile’ Logistics for On-Line Food Retail

    OpenAIRE

    Trienekens , Jacques; Hvolby , Hans-Henrik; Turner , Paul

    2017-01-01

    Part 2: Production Management in Food Supply Chains; International audience; Conventional approaches to logistics for food retail continue to be challenged by the rapid growth of on-line food retail. At the same time, ‘last mile’ logistics optimization for on-line retail also face challenges as changing consumer expectations, habits and purchasing patterns intersect with the increasing density of urban environments. Numerous considerations are already in play around servicing of last mile log...

  11. Last cast for the LHC

    CERN Multimedia

    2005-01-01

    The first major contract signed for the LHC is drawing to a close. Belgian firm Cockerill Sambre (a member of the Arcelor Group) has just completed production of 50,000 tonnes of steel sheets for the accelerator's superconducting magnet yokes, in what has proved to be an exemplary partnership with CERN. Philippe Lebrun, Head of the AT Department, Lyn Evans, LHC Project Leader, and Lucio Rossi, Head of the AT-MAS Group, in front of the last batch of steel for the LHC at Cockerill Sambre. It was a bright red-letter day at the end of May, when Belgian firm Cockerill Sambre of the Arcelor Group marked the completion of one of the largest contracts for the LHC machine by casting the last batch of steel sheets for the LHC superconducting magnet yokes in the presence of LHC Project Leader Lyn Evans, AT Department Head Philippe Lebrun, Magnets and Superconductors (AT-MAS) Group Leader Lucio Rossi and Head of the AT-MAS Group's components centre Francesco Bertinelli. The yokes constitute approximately 80% of the acc...

  12. Effects of post-fire logging on California spotted owl occupancy

    Directory of Open Access Journals (Sweden)

    Chad T. Hanson

    2018-01-01

    Full Text Available In fire-adapted forest ecosystems around the world, there has been growing concern about adverse impacts of post-fire logging on native biodiversity and ecological processes. This is also true in conifer forests of California, U.S.A. which are home to a rare and declining owl subspecies, the California spotted owl (Strix occidentalis occidentalis. While there has been recent concern about the California spotted owl occupancy in large fire areas where some territories have substantial high-severity fire effects, the influence of post-fire logging on the California spotted owl occupancy has been investigated very little, leading to some uncertainty about interpretation of conflicting results in different large fires. Research has found these owls preferentially select high-severity fire areas, characterised by high levels of snags and native shrubs, for foraging in forests that were not logged after fire, suggesting that removal of this foraging habitat might impact occupancy. The authors assessed the effect of post-fire logging and high-severity fire, on occupancy of this subspecies in eight large fire areas, within spotted owl sites with two different levels of high-severity fire effects. They found a significant adverse effect of such logging and no effect of high-severity fire alone. These results indicate it is post-fire logging, not large fires themselves, that poses a conservation threat to this imperilled species.

  13. Identifying APT Malware Domain Based on Mobile DNS Logging

    Directory of Open Access Journals (Sweden)

    Weina Niu

    2017-01-01

    Full Text Available Advanced Persistent Threat (APT is a serious threat against sensitive information. Current detection approaches are time-consuming since they detect APT attack by in-depth analysis of massive amounts of data after data breaches. Specifically, APT attackers make use of DNS to locate their command and control (C&C servers and victims’ machines. In this paper, we propose an efficient approach to detect APT malware C&C domain with high accuracy by analyzing DNS logs. We first extract 15 features from DNS logs of mobile devices. According to Alexa ranking and the VirusTotal’s judgement result, we give each domain a score. Then, we select the most normal domains by the score metric. Finally, we utilize our anomaly detection algorithm, called Global Abnormal Forest (GAF, to identify malware C&C domains. We conduct a performance analysis to demonstrate that our approach is more efficient than other existing works in terms of calculation efficiency and recognition accuracy. Compared with Local Outlier Factor (LOF, k-Nearest Neighbor (KNN, and Isolation Forest (iForest, our approach obtains more than 99% F-M and R for the detection of C&C domains. Our approach not only can reduce data volume that needs to be recorded and analyzed but also can be applicable to unsupervised learning.

  14. Generalized localization for the double trigonometric Fourier series and the Walsh-Fourier series of functions in L log +L log + log +L

    International Nuclear Information System (INIS)

    Bloshanskaya, S K; Bloshanskii, I L; Roslova, T Y

    1998-01-01

    For an arbitrary open set Ω subset of I 2 =[0,1) 2 and an arbitrary function f element of L log + L log + log + L(I 2 ) such that f=0 on Ω the double Fourier series of f with respect to the trigonometric system Ψ=E and the Walsh-Paley system Ψ=W is shown to converge to zero (over rectangles) almost everywhere on Ω. Thus, it is proved that generalized localization almost everywhere holds on arbitrary open subsets of the square I 2 for the double trigonometric Fourier series and the Walsh-Fourier series of functions in the class L log + L log + log + L (in the case of summation over rectangles). It is also established that such localization breaks down on arbitrary sets that are not dense in I 2 , in the classes Φ Ψ (L)(I 2 ) for the orthonormal system Ψ=E and an arbitrary function such that Φ E (u)=o(u log + log + u) as u→∞ or for Φ W (u)=u( log + log + u) 1-ε , 0<ε<1

  15. Permeability log using new lifetime measurements

    International Nuclear Information System (INIS)

    Dowling, D.J.; Boyd, J.F.; Fuchs, J.A.

    1975-01-01

    Comparative measurements of thermal neutron decay time are obtained for a formation after irradiation with a pulsed neutron source. Chloride ions in formation fluids are concentrated by the electrosmosis effect using charged poles on a well logging sonde. The formation is irradiated with fast neutrons and a first comparative measure of the thermal neutron decay time or neutron lifetime is taken. The chloride ions are then dispersed by acoustic pumping with a magnetostrictive transducer. The formation is then again irradiated with fast neutrons and a comparative measure of neutron lifetime is taken. The comparison is a function of the variation in chloride concentration between the two measurements which is related to formation permeability

  16. Pulsed neutron source well logging system

    International Nuclear Information System (INIS)

    Dillingham, M.E.

    1975-01-01

    A pulsed neutron source arrangement is provided in which a sealed cylindrical chamber encloses a rotatable rotor member carrying a plurality of elongated target strips of material which emits neutrons when bombarded with alpha particles emitted by the plurality of source material strips. The rotor may be locked in a so-called ON position by an electromagnetic clutch drive mechanism controllable from the earth's surface so as to permit the making of various types of logs utilizing a continuously emitting neutron source. (Patent Office Record)

  17. New radio meteor detecting and logging software

    Science.gov (United States)

    Kaufmann, Wolfgang

    2017-08-01

    A new piece of software ``Meteor Logger'' for the radio observation of meteors is described. It analyses an incoming audio stream in the frequency domain to detect a radio meteor signal on the basis of its signature, instead of applying an amplitude threshold. For that reason the distribution of the three frequencies with the highest spectral power are considered over the time (3f method). An auto notch algorithm is developed to prevent the radio meteor signal detection from being jammed by a present interference line. The results of an exemplary logging session are discussed.

  18. Zope based electronic operation log system - Zlog

    International Nuclear Information System (INIS)

    Yoshii, K.; Satoh, Y.; Kitabayashi, T.

    2004-01-01

    Since January 2004, the Zope based electronic operation logging system, named Zlog, has been running at the KEKB and AR accelerator facilities. Since Zope is the python based open source web application server software and python language is familiar for the members in the KEKB accelerator control group, we have developed the Zlog system rapidly. In this paper, we report the development history and the present status of Zlog system. Also we show some general plug-in components, called Zope products, have been useful for our Zlog development. (author)

  19. Landscape-scale changes in forest canopy structure across a partially logged tropical peat swamp

    Science.gov (United States)

    Wedeux, B. M. M.; Coomes, D. A.

    2015-11-01

    Forest canopy structure is strongly influenced by environmental factors and disturbance, and in turn influences key ecosystem processes including productivity, evapotranspiration and habitat availability. In tropical forests increasingly modified by human activities, the interplay between environmental factors and disturbance legacies on forest canopy structure across landscapes is practically unexplored. We used airborne laser scanning (ALS) data to measure the canopy of old-growth and selectively logged peat swamp forest across a peat dome in Central Kalimantan, Indonesia, and quantified how canopy structure metrics varied with peat depth and under logging. Several million canopy gaps in different height cross-sections of the canopy were measured in 100 plots of 1 km2 spanning the peat dome, allowing us to describe canopy structure with seven metrics. Old-growth forest became shorter and had simpler vertical canopy profiles on deeper peat, consistent with previous work linking deep peat to stunted tree growth. Gap size frequency distributions (GSFDs) indicated fewer and smaller canopy gaps on the deeper peat (i.e. the scaling exponent of Pareto functions increased from 1.76 to 3.76 with peat depth). Areas subjected to concessionary logging until 2000, and illegal logging since then, had the same canopy top height as old-growth forest, indicating the persistence of some large trees, but mean canopy height was significantly reduced. With logging, the total area of canopy gaps increased and the GSFD scaling exponent was reduced. Logging effects were most evident on the deepest peat, where nutrient depletion and waterlogged conditions restrain tree growth and recovery. A tight relationship exists between canopy structure and peat depth gradient within the old-growth tropical peat swamp forest. This relationship breaks down after selective logging, with canopy structural recovery, as observed by ALS, modulated by environmental conditions. These findings improve our

  20. Well logging. Acquisition and applications; Diagraphies. Acquisition et applications

    Energy Technology Data Exchange (ETDEWEB)

    Serra, O.; Serra, L.

    2001-07-01

    This reference book on wire-line and LWD well logging covers all geophysical methods of underground survey in a synthetic, visual and dynamical way. It treats of: the physical principle of well logging measurements, the different types of existing probes, the factors that can influence the measurements, and the applications of these measurements. The following well-logging methods are reviewed: resistivity; electromagnetic wave propagation; magnetic susceptibility and magnetic field; spontaneous potential; nuclear logging: natural gamma radioactivity, density logging, photoelectric index, neutron emission probes, hydrogen index or neutron porosity, neutron induced gamma spectroscopy, neutron relaxation time, NMR; acoustic measurements: sonic logging, seismic profiles; texture, structure and stratigraphy data acquisition; borehole diameter measurement; temperature measurement; wire sampling methods; place and role of well-logging in petroleum exploration; well-logging programs. (J.S.)

  1. Shiitake mushroom production on small diameter oak logs in Ohio

    Science.gov (United States)

    S.M. Bratkovich

    1991-01-01

    Yields of different strains of shiitake mushrooms (Lentinus edodes) were evaluated when produced on small diameter oak logs in Ohio. Logs averaging between 3-4 inches in diameter were inoculated with four spawn strains in 1985.

  2. LAST REMINDER: GSM Operator change

    CERN Multimedia

    2003-01-01

    CERN changes its mobile phone operator on 5th January 2004. Your old SIM card and number +41 79 201 XXXX will no longer be valid. Your new number will be +41 76 487 XXXX, but still 16 XXXX inside the CERN area. Your last four digits do not change. To obtain your new SIM card, please fill in the web form at http://it-service-gsm.web.cern.ch/it-service-gsm/ or call tel. 76111 if you do not have access to the web. Dates and places for the distribution of the new SIM cards are: - Meyrin site: Building 504, Restaurant 2, from 26/11 to 5/12; - Prevessin site: Building 866, Restaurant 3, room R-11, from 8/12 to 12/12.

  3. Log and tree sawing times for hardwood mills

    Science.gov (United States)

    Everette D. Rast

    1974-01-01

    Data on 6,850 logs and 1,181 trees were analyzed to predict sawing times. For both logs and trees, regression equations were derived that express (in minutes) sawing time per log or tree and per Mbf. For trees, merchantable height is expressed in number of logs as well as in feet. One of the major uses for the tables of average sawing times is as a bench mark against...

  4. Log-Log Convexity of Type-Token Growth in Zipf's Systems

    Science.gov (United States)

    Font-Clos, Francesc; Corral, Álvaro

    2015-06-01

    It is traditionally assumed that Zipf's law implies the power-law growth of the number of different elements with the total number of elements in a system—the so-called Heaps' law. We show that a careful definition of Zipf's law leads to the violation of Heaps' law in random systems, with growth curves that have a convex shape in log-log scale. These curves fulfill universal data collapse that only depends on the value of Zipf's exponent. We observe that real books behave very much in the same way as random systems, despite the presence of burstiness in word occurrence. We advance an explanation for this unexpected correspondence.

  5. Data Cleaning Methods for Client and Proxy Logs

    NARCIS (Netherlands)

    Weinreich, H.; Obendorf, H.; Herder, E.; Edmonds, A.; Hawkey, K.; Kellar, M.; Turnbull, D.

    2006-01-01

    In this paper we present our experiences with the cleaning of Web client and proxy usage logs, based on a long-term browsing study with 25 participants. A detailed clickstream log, recorded using a Web intermediary, was combined with a second log of user interface actions, which was captured by a

  6. Sediment transport and soil disturbance after postfire logging.

    Science.gov (United States)

    James D. McIver

    2003-01-01

    Recently there has been considerable debate on the practice of postfire logging, in which burned forests are entered soon after fire to recover commercially valuable trees. Proponents of the practice argue that postfire logging is part of a 'restoration package' that can be used to control erosion (e.g., contour logging) and can help to mitigate costs of...

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

    Science.gov (United States)

    Mostow, Jack; Beck, Joseph E.

    2009-01-01

    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…

  8. Economic incentives exist to support measures to reduce illegal logging

    Science.gov (United States)

    J.A. Turner; J. Buongiorno; A. Katz; S. Zhu; R. Li

    2008-01-01

    Three studies of the global economic implications of eliminating illegal logging are summarized. Processors of illegally sourced wood would lose from the elimination of illegal logging through high prices for logs and decreased production of wood products. Associated with these changes could be losses in employment and income. Beyond these losses to the processing...

  9. A survey of animal-powered logging in Alabama

    Science.gov (United States)

    Christopher W. Toms; Mark R. Dubois; John C. Bliss; John H. Wilhoit; Robert B. Rummer

    2001-01-01

    In a state with a very large, highly mechanized timber harvesting industry, animal-powered logging still occupies a niche in Alabama as a small-scale harvesting alternative. This article summarizes the results from a study that examined the extent of animal logging in Alabama. We investigated this topic by asking who is logging with animals, where are they working,...

  10. Interactive machine learning for postprocessing CT images of hardwood logs

    Science.gov (United States)

    Erol Sarigul; A. Lynn Abbott; Daniel L. Schmoldt

    2003-01-01

    This paper concerns the nondestructive evaluation of hardwood logs through the analysis of computed tomography (CT) images. Several studies have shown that the commercial value of resulting boards can be increased substantially if log sawing strategies are chosen using prior knowledge of internal log defects. Although CT imaging offers a potential means of obtaining...

  11. Financial and Economic Analysis of Reduced Impact Logging

    Science.gov (United States)

    Tom Holmes

    2016-01-01

    Concern regarding extensive damage to tropical forests resulting from logging increased dramatically after World War II when mechanized logging systems developed in industrialized countries were deployed in the tropics. As a consequence, tropical foresters began developing logging procedures that were more environmentally benign, and by the 1990s, these practices began...

  12. Environmental effects of postfire logging: literature review and annotated bibliography.

    Science.gov (United States)

    James D. McIver; Lynn Starr

    2000-01-01

    The scientific literature on logging after wildfire is reviewed, with a focus on environmental effects of logging and removal of large woody structure. Rehabilitation, the practice of planting or seeding after logging, is not reviewed here. Several publications are cited that can be described as “commentaries,” intended to help frame the public debate. We review 21...

  13. Utilization and cost of log production from animal loging operations

    Science.gov (United States)

    Suraj P. Shrestha; Bobby L. Lanford; Robert B. Rummer; Mark Dubois

    2006-01-01

    Forest harvesting with animals is a labor-intensive operation. It is expensive to use machines on smaller woodlots, which require frequent moves if mechanically logged. So, small logging systems using animals may be more cost effective. In this study, work sampling was used for five animal logging operations in Alabama to measure productive and non-productive time...

  14. Ultrafast CT scanning of an oak log for internal defects

    Science.gov (United States)

    Francis G. Wagner; Fred W. Taylor; Douglas S. Ladd; Charles W. McMillin; Fredrick L. Roder

    1989-01-01

    Detecting internal defects in sawlogs and veneer logs with computerized tomographic (CT) scanning is possible, but has been impractical due to the long scanning time required. This research investigated a new scanner able to acquire 34 cross-sectional log scans per second. This scanning rate translates to a linear log feed rate of 85 feet (25.91 m) per minute at one...

  15. Technology development for high temperature logging tools

    Energy Technology Data Exchange (ETDEWEB)

    Veneruso, A.F.; Coquat, J.A.

    1979-01-01

    A set of prototype, high temperature logging tools (temperature, pressure and flow) were tested successfully to temperatures up to 275/sup 0/C in a Union geothermal well during November 1978 as part of the Geothermal Logging Instrumentation Development Program. This program is being conducted by Sandia Laboratories for the Department of Energy's Division of Geothermal Energy. The progress and plans of this industry based program to develop and apply the high temperature instrumentation technology needed to make reliable geothermal borehole measurements are described. Specifically, this program is upgrading existing sondes for improved high temperature performance, as well as applying new materials (elastomers, polymers, metals and ceramics) and developing component technology such as high temperature cables, cableheads and electronics to make borehole measurements such as formation temperature, flow rate, high resolution pressure and fracture mapping. In order to satisfy critical existing needs, the near term goal is for operation up to 275/sup 0/C and 7000 psi by the end of FY80. The long term goal is for operation up to 350/sup 0/C and 20,000 psi by the end of FY84.

  16. Public PCs: Log Out or Lose Out

    CERN Multimedia

    Computer Security Team

    2013-01-01

    Do you regularly use one of the public Windows or Linux terminals in the CERN library or in front of the Users' Office? Or do you often give presentations or run meetings, workshops or conferences? Did you recently attend a training session in the CERN Training Centre? If you answered at least once with “yes”, we have a plea for you: LOG OUT when done in order to protect your data!   You might recall that CERN considers that “Your Privacy is Paramount”. But this does not come for free. In the few past months, we have received several reports from vigilant people who have spotted open user sessions on public PCs at CERN. Those users simply forgot to log out once their work, training or meeting was over. Their session continued without them being present. Worse, with CERN using a central Single Sign-On (SSO) portal, their login credentials would allow a malicious person at CERN to use those credentials to access that user’s mailbox, DFS ...

  17. Dual excitation acoustic paramagnetic logging tool

    Energy Technology Data Exchange (ETDEWEB)

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

    1989-01-01

    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.

  18. Radiation incident in oil well logging

    International Nuclear Information System (INIS)

    Lozada, J.A.

    1998-01-01

    On June 4th 1997 equipment failure and violation of approved procedures by a crew of workers initiated a series of events that resulted in the unnecessary exposure to neutron and gamma radiation, from a 666 GBq Am 241 Be source, of forty two workers from a well logging company in Venezuela. Due to the presence of dry mud or drilling fluids inside the logging tool, the nosepiece was screwed off the rest of the source holder; this piece was mistaken for the entire source holder thus leaving the source inside the tool. The tool was labelled for maintenance and electronic laboratory personal worked near the source for seven hours before they identify its presence. As soon as the incident was detected a contingency plan was implemented and the source could be retrieved from the tool and placed in its shipping container. The TLD badges indicate doses well below the annual limit of 20 mSv, and none of the workers involved in the incident seem to show serious health consequences from it. After the incident, in order to avoid the occurrence of similar situations, a better source and tool maintenance program was implemented, all the workers were re-trained, and area monitors were installed in all operations bases. (author)

  19. Temporal Decay in Timber Species Composition and Value in Amazonian Logging Concessions.

    Science.gov (United States)

    Richardson, Vanessa A; Peres, Carlos A

    2016-01-01

    Throughout human history, slow-renewal biological resource populations have been predictably overexploited, often to the point of economic extinction. We assess whether and how this has occurred with timber resources in the Brazilian Amazon. The asynchronous advance of industrial-scale logging frontiers has left regional-scale forest landscapes with varying histories of logging. Initial harvests in unlogged forests can be highly selective, targeting slow-growing, high-grade, shade-tolerant hardwood species, while later harvests tend to focus on fast-growing, light-wooded, long-lived pioneer trees. Brazil accounts for 85% of all native neotropical forest roundlog production, and the State of Pará for almost half of all timber production in Brazilian Amazonia, the largest old-growth tropical timber reserve controlled by any country. Yet the degree to which timber harvests beyond the first-cut can be financially profitable or demographically sustainable remains poorly understood. Here, we use data on legally planned logging of ~17.3 million cubic meters of timber across 314 species extracted from 824 authorized harvest areas in private and community-owned forests, 446 of which reported volumetric composition data by timber species. We document patterns of timber extraction by volume, species composition, and monetary value along aging eastern Amazonian logging frontiers, which are then explained on the basis of historical and environmental variables. Generalized linear models indicate that relatively recent logging operations farthest from heavy-traffic roads are the most selective, concentrating gross revenues on few high-value species. We find no evidence that the post-logging timber species composition and total value of forest stands recovers beyond the first-cut, suggesting that the commercially most valuable timber species become predictably rare or economically extinct in old logging frontiers. In avoiding even more destructive land-use patterns, managing

  20. Rill erosion in burned and salvage logged western montane forests: Effects of logging equipment type, traffic level, and slash treatment

    Science.gov (United States)

    J. W. Wagenbrenner; P. R. Robichaud; R. E. Brown

    2016-01-01

    Following wildfires, forest managers often consider salvage logging burned trees to recover monetary value of timber, reduce fuel loads, or to meet other objectives. Relatively little is known about the cumulative hydrologic effects of wildfire and subsequent timber harvest using logging equipment. We used controlled rill experiments in logged and unlogged (control)...

  1. Determination of the rock clayiness from statistically standardized gamma-logging diagrams

    International Nuclear Information System (INIS)

    Kholodilov, V.V.

    1975-01-01

    Statistical standardization (using mathematical expectancy and dispersion) was done on gamma-logging diagrams made from 43 boreholes in producing strata of mid Jurassic and lower Cretaceous deposits in the Dagestan Plain. The material of the deposits is chiefly sands and aleurites containing 5 to 45% clay. The dependence of the standard deviation of the gamma-log curves on the clayiness of the rocks was determined at intervals of 400 and 300 meters. The intervals were selected by considering the borehole depth. The coefficients of correlation were 0.87 and 0.86, respectively

  2. Use of pulsed neutron logging to evaluate perforation washing

    International Nuclear Information System (INIS)

    Dimon, C.A.

    1986-01-01

    This invention relates to the use of pulsed neutron logging techniques before and after perforation washing operations are performed to evaluate the degree of success of the perforation washing operations. Well logging operations of a type designed to respond to the difference between a formation immediately behind the well sheath and voids in the formation are performed both before and after the perforation washing operation. differences between the two resulting logs are then indicative of voids created by perforation washing. In a preferred embodiment, pulsed neutron logging is used as the logging technique, while a weighted brine having a high absorption cross section to pulsed neutrons is used as the perforation washing fluid

  3. Study of the reservoirs of Jurassic and Cretaceous periods in the south-cast slope of Central Kara-Kum vault using combination of acoustic logging, neutron-gamma logging, gamma logging, and electrical logging

    International Nuclear Information System (INIS)

    Meredov, T.M.; Baranov, M.I.

    1978-01-01

    Considered is the possibility of application of the combination of neutron-gamma logging, gamma logging al partitioncoustic logging and electrical logging to lithologica of sections, discovery reservoir layers in carbonate and terrigeneous sections as well as quantitative estimation of the porosity coefficients values at prospecting areas in the south-east slope of Central Kara-Kum vault. Neutron-gamma logging mostly makes it possible to partition carbonate rocks into limestones, dolomites and their interstitial variaties and to indicate sand stone layers with different degree of carbonate content

  4. KFM 01A. Q-logging

    International Nuclear Information System (INIS)

    Barton, Nick

    2003-03-01

    The first Forsmark potential repository site borehole KFM 01A provided core from 101.8 to 1000.7 m depth. This was independently Q-logged during a two-day period (19th-20th February, 2003), without access to BORMAP results or regional jointing frequencies or orientations. The Q-logging was intended to be an independent check for subsequent BORMAP-derived Q-parameter estimation. The Q-logging was accomplished using the manually-recorded 'histogram method' which allows the logger to enter Q-parameter ranges and depths directly into the appropriate histograms, which facilitates subsequent data processing using Excel spreadsheets. Successive pairs of core boxes, which contain an average of 11 meters of core in ten rows, were the source of ten opinions of each of the six Q-parameters, giving a total of 4920 recordings of Q-parameter values for the 164 core boxes. Data processing was divided into several parts, with successively increasing detail. The report therefore contains Q-histograms for the whole core, for four identified fracture(d) zones combined as if one unit, and then for the whole core minus these fracture(d) zones. This background rock mass quality is subsequently divided into nine depth zones or slices, and trends of variation with depth are tabulated. The four identified fracture(d) zones, which are actually of reasonable quality, are also analysed separately, and similarities and subtle differences are discerned between them. The overall quality of this first core is very good to excellent, with Q(mean) of 48.4, and a most frequent Q-value of 100. The range of quality is from 2.1 to 2130, which is the complete upper half of the six order of magnitude Q scale. Even the relatively fracture(d) zones, representing some 13% of the 900 m cored, have a combined Q(mean) of 13.9 and a range of quality of 2.1 to 150

  5. Linking Hunter Knowledge with Forest Change to Understand Changing Deer Harvest Opportunities in Intensively Logged Landscapes

    Directory of Open Access Journals (Sweden)

    Todd J. Brinkman

    2009-06-01

    Full Text Available The effects of landscape changes caused by intensive logging on the availability of wild game are important when the harvest of wild game is a critical cultural practice, food source, and recreational activity. We assessed the influence of extensive industrial logging on the availability of wild game by drawing on local knowledge and ecological science to evaluate the relationship between forest change and opportunities to harvest Sitka black-tailed deer (Odocoileus hemionus sitkensis on Prince of Wales Island, Alaska. We used data collected through interviews with local deer hunters and GIS analysis of land cover to determine relationships among landscape change, hunter access, and habitat for deer hunting over the last 50 yr. We then used these relationships to predict how harvest opportunities may change in the future. Intensive logging from 1950 into the 1990s provided better access to deer and habitat that facilitated deer hunting. However, successional changes in intensively logged forests in combination with a decline in current logging activity have reduced access to deer and increased undesirable habitat for deer hunting. In this new landscape, harvest opportunities in previously logged landscapes have declined, and hunters identify second-growth forest as one of the least popular habitats for hunting. Given the current state of the logging industry in Alaska, it is unlikely that the logging of the remaining old-growth forests or intensive management of second-growth forests will cause hunter opportunities to rebound to historic levels. Instead, hunter opportunities may continue to decline for at least another human generation, even if the long-term impacts of logging activity and deer harvest on deer numbers are minimal. Adapting hunting strategies to focus on naturally open habitats such as alpine and muskeg that are less influenced by external market forces may require considerably more hunting effort but provide the best option for

  6. Method and apparatus for logging inclined earth boreholes

    International Nuclear Information System (INIS)

    Youmans, A.H.

    1981-01-01

    An improved technique is provided for comparing the velocity of an elongated well logging instrument traversing an inclined earth borehole with the playout velocity of the well logging cable at the earth's surface to control both the cable hoist drum rotation and the rate of movement of the subsurface instrument and thus insure cable playout is in equilibrium with the logging instrument movement. Method and apparatus are described for detecting any reduction in movement of the logging instrument through the borehole and for reducing the velocity of the logging cable playout in response thereto by reducing drum rotation. Further, when the velocity of cable playout slows to a preselected value, a monitoring circuit generates control signals which actuate a means of power attached to or integral with the logging instrument which, upon initiation, apply a force to move the logging instrument upward or downward within the borehole

  7. DOE-Grand Junction logging model data synopsis

    International Nuclear Information System (INIS)

    Mathews, M.A.; Koizumi, C.J.; Evans, H.B.

    1978-05-01

    This synopsis provides the available data concerning the logging models at the DoE-Grand Junction facility, to date (1976). Because gamma-ray logs are used in uranium exploration to estimate the grade (percent U 3 O 8 ) and the thickness of uranium ore zones in exploration drill holes, logging models are required to calibrate the gamma-ray logging equipment in order to obtain accuracy, uniformity, standardization, and repeatability during logging. This quality control is essential for accurate ore reserve calculations and for estimates of ore potential. The logging models at the DoE-Grand Junction facility are available for use by private industry in calibrating their gamma-ray logging equipment. 21 figures, 26 tables

  8. Applicability estimation of flowmeter logging for detecting hydraulic pass

    International Nuclear Information System (INIS)

    Miyakawa, Kimio; Tanaka, Yasuji; Tanaka, Kazuhiro

    1997-01-01

    Estimation of the hydraulic pass governing hydrogeological structure contributes significantly to the siting HLW repository. Flowmeter logging can detect hydraulic passes by measuring vertical flow velocity of groundwater in the borehole. We reviewed application of this logging in situ. The hydraulic pass was detected with combination of ambient flow logging, with pumping and/or injecting induced flow logging. This application showed that the flowmeter logging detected hydraulic passes conveniently and accurately compared with other hydraulic tests. Hydraulic conductivity by using flowmeter logging was assessed above 10 -6 m/sec and within one order from comparison with injection packer tests. We suggest that appropriate application of the flowmeter logging for the siting is conducted before hydraulic tests because test sections and monitoring sections are decided rationally for procurement of quantitative hydraulic data. (author)

  9. Acoustic--nuclear permeability logging system

    International Nuclear Information System (INIS)

    Dowling, D.J.; Arnold, D.M.

    1978-01-01

    A down hole logging tool featuring a neutron generator, an acoustic disturbance generator, and a radiation detection system is described. An array of acoustic magnetostriction transducers is arranged about the target of a neutron accelerator. Two gamma ray sensors are separated from the accelerator target by shielding. According to the method of the invention, the underground fluid at the level of a formation is bombarded by neutrons which react with oxygen in the fluid to produce unstable nitrogen 16 particles according to the reaction 16 O(n,p) 16 N. Acoustic pulses are communicated to the fluid, and are incident on the boundary of the borehole at the formation. The resulting net flow of fluid across the boundary is determined from radiation detection measurements of the decaying 16 N particles in the fluid. A measure of the permeability of the formation is obtained from the determination of net fluid flow across the boundary

  10. Logging-while-drilling (LWD) pressure test

    Energy Technology Data Exchange (ETDEWEB)

    Thirud, Aase P.

    2003-07-01

    Statoil and Halliburton have completed a successful test of a new ground-breaking formation evaluation technology on the Norwegian shelf. An LWD formation tester, the GeoTapTM sensor, was used to quantify formation pressure during drilling operations. The inaugural job was completed by Halliburton's Sperry-Sun product service line onboard the Bideford Dolphin at the Borg Field while drilling a horizontal production well in the Vigdis Extension development. The GeoTap tool, part of Sperry-Sun's StellarTM MWD/LWT suite, was run in combination with a complete logging-while-drilling sensor package and the Geo-Pilot rotary steerable drilling system. Repeat formation pressures were taken and successfully transmitted to surface. This is the first time this type of technology has been successfully applied on the Norwegian shelf.

  11. Neutron die-away well logging

    International Nuclear Information System (INIS)

    Jacobson, L.A.

    1976-01-01

    Neutron die-away well logging is extensively used for the location and monitoring of hydrocarbon zones in cased wells. Casing prohibits the use of conventional open-hole electrical resistivity methods. Through an appropriate interpretation of the measured capture cross-section, it is possible to determine the fractional hydrocarbon content of the rock pore volume, provided that the interstitial water is moderately saline (Σ/sub w/ greater than or equal to .035 cm -1 ). Special sealed D-T accelerator tubes and high voltage supplies have been developed for this purpose. They must fit into a 25 mm design circle and operate at 175 0 C, producing approximately 10 8 neutron/sec average in repetitive bursts. In the Schlumberger method an electronic servo-system adjusts burst and measure-gate timing to minimize statistical uncertainty regardless of die-away time

  12. Water injection profiling by nuclear logging

    International Nuclear Information System (INIS)

    Arnold, D.M.

    1980-01-01

    This invention relates to nuclear logging techniques for determining the volume flow rates and flow directions of injected water moving behind a wellbore casing. The apparatus includes a sonde equipped with a neutron source and dual radiation detectors. Oxygen in the neutron irradiated water is transmitted to 16 N and the resultant primary and Compton scattered gamma rays are detected in two energy windows by both detectors. Count rate data is analysed in terms of the windows to obtain linear flow velocities for water flow within and behind the casing. Volume flow rates are determined for upward and downward flow, and horizontal volume flow into the surrounding formation is calculated. A complete injection profile may thus be obtained. (U.K.)

  13. Simulation Control Graphical User Interface Logging Report

    Science.gov (United States)

    Hewling, Karl B., Jr.

    2012-01-01

    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.

  14. Nut Production in Bertholletia excelsa across a Logged Forest Mosaic: Implications for Multiple Forest Use

    Science.gov (United States)

    Rockwell, Cara A.; Guariguata, Manuel R.; Menton, Mary; Arroyo Quispe, Eriks; Quaedvlieg, Julia; Warren-Thomas, Eleanor; Fernandez Silva, Harol; Jurado Rojas, Edwin Eduardo; Kohagura Arrunátegui, José Andrés Hideki; Meza Vega, Luis Alberto; Revilla Vera, Olivia; Valera Tito, Jonatan Frank; Villarroel Panduro, Betxy Tabita; Yucra Salas, Juan José

    2015-01-01

    Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world’s most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1–2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich

  15. Nut Production in Bertholletia excelsa across a Logged Forest Mosaic: Implications for Multiple Forest Use.

    Directory of Open Access Journals (Sweden)

    Cara A Rockwell

    Full Text Available Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae is one of the world's most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013 in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80% of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1-2 timber trees removed per ha. In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09 P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil

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

    Science.gov (United States)

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

    2013-03-01

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

  17. Last Glacial Maximum Salinity Reconstruction

    Science.gov (United States)

    Homola, K.; Spivack, A. J.

    2016-12-01

    It has been previously demonstrated that salinity can be reconstructed from sediment porewater. The goal of our study is to reconstruct high precision salinity during the Last Glacial Maximum (LGM). Salinity is usually determined at high precision via conductivity, which requires a larger volume of water than can be extracted from a sediment core, or via chloride titration, which yields lower than ideal precision. It has been demonstrated for water column samples that high precision density measurements can be used to determine salinity at the precision of a conductivity measurement using the equation of state of seawater. However, water column seawater has a relatively constant composition, in contrast to porewater, where variations from standard seawater composition occur. These deviations, which affect the equation of state, must be corrected for through precise measurements of each ion's concentration and knowledge of apparent partial molar density in seawater. We have developed a density-based method for determining porewater salinity that requires only 5 mL of sample, achieving density precisions of 10-6 g/mL. We have applied this method to porewater samples extracted from long cores collected along a N-S transect across the western North Atlantic (R/V Knorr cruise KN223). Density was determined to a precision of 2.3x10-6 g/mL, which translates to salinity uncertainty of 0.002 gms/kg if the effect of differences in composition is well constrained. Concentrations of anions (Cl-, and SO4-2) and cations (Na+, Mg+, Ca+2, and K+) were measured. To correct salinities at the precision required to unravel LGM Meridional Overturning Circulation, our ion precisions must be better than 0.1% for SO4-/Cl- and Mg+/Na+, and 0.4% for Ca+/Na+, and K+/Na+. Alkalinity, pH and Dissolved Inorganic Carbon of the porewater were determined to precisions better than 4% when ratioed to Cl-, and used to calculate HCO3-, and CO3-2. Apparent partial molar densities in seawater were

  18. Making lasting memories: Remembering the significant

    Science.gov (United States)

    McGaugh, James L.

    2013-01-01

    Although forgetting is the common fate of most of our experiences, much evidence indicates that emotional arousal enhances the storage of memories, thus serving to create, selectively, lasting memories of our more important experiences. The neurobiological systems mediating emotional arousal and memory are very closely linked. The adrenal stress hormones epinephrine and corticosterone released by emotional arousal regulate the consolidation of long-term memory. The amygdala plays a critical role in mediating these stress hormone influences. The release of norepinephrine in the amygdala and the activation of noradrenergic receptors are essential for stress hormone-induced memory enhancement. The findings of both animal and human studies provide compelling evidence that stress-induced activation of the amygdala and its interactions with other brain regions involved in processing memory play a critical role in ensuring that emotionally significant experiences are well-remembered. Recent research has determined that some human subjects have highly superior autobiographic memory of their daily experiences and that there are structural differences in the brains of these subjects compared with the brains of subjects who do not have such memory. Understanding of neurobiological bases of such exceptional memory may provide additional insights into the processes underlying the selectivity of memory. PMID:23754441

  19. A novel approach proposed for fractured zone detection using petrophysical logs

    International Nuclear Information System (INIS)

    Tokhmechi, B; Memarian, H; Noubari, H A; Moshiri, B

    2009-01-01

    Fracture detection is a key step in wellbore stability and fractured reservoir fluid flow simulation. While different methods have been proposed for fractured zones detection, each of them is associated with certain shortcomings that prevent their full use in different related engineering applications. In this paper, a novel combined method is proposed for fractured zone detection, using processing of petrophysical logs with wavelet, classification and data fusion techniques. Image and petrophysical logs from Asmari reservoir in eight wells of an oilfield in southwestern Iran were used to investigate the accuracy and applicability of the proposed method. Initially, an energy matching strategy was utilized to select the optimum mother wavelets for de-noising and decomposition of petrophysical logs. Parzen and Bayesian classifiers were applied to raw, de-noised and various frequency bands of logs after decomposition in order to detect fractured zones. Results show that the low-frequency bands (approximation 2, a 2 ) of de-noised logs are the best data for fractured zones detection. These classifiers considered one well as test well and the other seven wells as train wells. Majority voting, optimistic OWA (ordered weighted averaging) and pessimistic OWA methods were used to fuse the results obtained from seven train wells. Results confirmed that Parzen and optimistic OWA are the best combined methods to detect fractured zones. The generalization of method is confirmed with an average accuracy of about 72%

  20. Specific features of well logging of boreholes drilled on electrical nonconducting solutions

    International Nuclear Information System (INIS)

    Ruchkin, A.F.; Fomenko, V.G.

    1978-01-01

    Methods for identification of permeable strata and determination of their porosity and oil-gas saturation using standard combination of geophysical investigations in the boreholes drilled with nonaqueous and inert drilling fluids are considered. Geophysical combination consists of the methods indications of which are independent on electrical conductivity of drilling fluids. They are all modifications of radioactivity logging (gamma logging, neutron logging, neutron-gamma logging, gamma-gamma logging, pulsed neutron logging, nuclear-magnetic logging), acoustic logging and thermal logging

  1. Development of an Intelligent System to Synthesize Petrophysical Well Logs

    Directory of Open Access Journals (Sweden)

    Morteza Nouri Taleghani

    2013-07-01

    Full Text Available Porosity is one of the fundamental petrophysical properties that should be evaluated for hydrocarbon bearing reservoirs. It is a vital factor in precise understanding of reservoir quality in a hydrocarbon field. Log data are exceedingly crucial information in petroleum industries, for many of hydrocarbon parameters are obtained by virtue of petrophysical data. There are three main petrophysical logging tools for the determination of porosity, namely neutron, density, and sonic well logs. Porosity can be determined by the use of each of these tools; however, a precise analysis requires a complete set of these tools. Log sets are commonly either incomplete or unreliable for many reasons (i.e. incomplete logging, measurement errors, and loss of data owing to unsuitable data storage. To overcome this drawback, in this study several intelligent systems such as fuzzy logic (FL, neural network (NN, and support vector machine are used to predict synthesized petrophysical logs including neutron, density, and sonic. To accomplish this, the petrophysical well logs data were collected from a real reservoir in one of Iran southwest oil fields. The corresponding correlation was obtained through the comparison of synthesized log values with real log values. The results showed that all intelligent systems were capable of synthesizing petrophysical well logs, but SVM had better accuracy and could be used as the most reliable method compared to the other techniques.

  2. Pulsed neutron uranium borehole logging with prompt fission neutrons

    International Nuclear Information System (INIS)

    Bivens, H.M.; Smith, G.W.; Jensen, D.H.

    1976-01-01

    The gross count natural gamma log normally used for uranium borehole logging is seriously affected by disequilibrium. Methods for the direct measurement of uranium, such as neutron logging, which are not affected by disequilibrium have been the object of considerable effort in recent years. This paper describes a logging system for uranium which uses a small accelerator to generate pulses of 14 MeV neutrons to detect and assay uranium by the measurement of prompt fission neutrons in the epithermal energy range. After an initial feasibility study, a prototype logging probe was built for field evaluation which began in January 1976. Physical and operational characteristics of the prototype probe, the neutron tube-transformer assembly, and the neutron tube are described. In logging operations, only the epithermal prompt fission neutrons detected between 250 microseconds to 2500 microseconds following the excitation neutron pulse are counted. Comparison of corrected neutron logs with the conventional gross count natural gamma logs and the chemical assays of cores from boreholes are shown. The results obtained with this neutron probe clearly demonstrate its advantages over the gross count natural gamma log, although at this time the accuracy of the neutron log assay is not satisfactory under some conditions. The necessary correction factors for various borehole and formation parameters are being determined and, when applied, should improve the assay accuracy

  3. Intelligent approaches for the synthesis of petrophysical logs

    International Nuclear Information System (INIS)

    Rezaee, M Reza; Kadkhodaie-Ilkhchi, Ali; Alizadeh, Pooya Mohammad

    2008-01-01

    Log data are of prime importance in acquiring petrophysical data from hydrocarbon reservoirs. Reliable log analysis in a hydrocarbon reservoir requires a complete set of logs. For many reasons, such as incomplete logging in old wells, destruction of logs due to inappropriate data storage and measurement errors due to problems with logging apparatus or hole conditions, log suites are either incomplete or unreliable. In this study, fuzzy logic and artificial neural networks were used as intelligent tools to synthesize petrophysical logs including neutron, density, sonic and deep resistivity. The petrophysical data from two wells were used for constructing intelligent models in the Fahlian limestone reservoir, Southern Iran. A third well from the field was used to evaluate the reliability of the models. The results showed that fuzzy logic and artificial neural networks were successful in synthesizing wireline logs. The combination of the results obtained from fuzzy logic and neural networks in a simple averaging committee machine (CM) showed a significant improvement in the accuracy of the estimations. This committee machine performed better than fuzzy logic or the neural network model in the problem of estimating petrophysical properties from well logs

  4. One less trip : logging with less tripping, more protection

    Energy Technology Data Exchange (ETDEWEB)

    Byfield, M.

    2005-12-15

    New logging technology by Datalog Technology Inc. was described. Logging-while-tripping (LWT) technology uses a slim petrophysical sensor package that is moved to the targeted geological formation through a drill pipe, which reduces the exposure to vibration and shock involved in logging-while-drilling (LWD). The equipment features standard components in a patented configuration and comes in 2 segments: the receiver sub and the sensor package electronics. A receiver sub is inserted into the bottomhole assembly at the end of the drill string. Drilling progresses with the LWT sub in the bottomhole assembly until the borehole approaches the logging depth. The sensor package and electronics are then lowered into the drill string. If the well is horizontal, rig pumps push the package into the drill string until it lands in the LWT sub. Drill pipes are moved across the zone of interest and logs are recorded on downhole memory contained within the LWT package. As the logging operation progresses, a depth recorder at the surface records depth information along with the downhole recorders. When logging is completed, downhole tools are retrieved, and data downloaded from the LWT onboard memory is merged with the surface depth information to generate well logs. Retrieval via the drill string greatly reduces the risk of losing the logging gear, which contains radioactive material. Federal officials now routinely insist on extensive fishing operations to retrieve lost tools. If a well gets a gas kick while logging is in progress, the operator can still pump down mud or close the blowout preventer rams if necessary, and save time in determining where to perforate shallow gas wells. Compensated neutron logs, gamma rays, spectrum gamma rays, and induction have been tested with the LWT system. It was concluded that Petro-Canada has deployed the logs recently and has achieved results that compared satisfactorily with conventional logs. 2 figs.

  5. The 'last mile' of data handling: Fermilab's IFDH tools

    International Nuclear Information System (INIS)

    Lyon, Adam L; Mengel, Marc W

    2014-01-01

    IFDH (Intensity Frontier Data Handling), is a suite of tools for data movement tasks for Fermilab experiments and is an important part of the FIFE[2] (Fabric for Intensity Frontier [1] Experiments) initiative described at this conference. IFDH encompasses moving input data from caches or storage elements to compute nodes (the 'last mile' of data movement) and moving output data potentially to those caches as part of the journey back to the user. IFDH also involves throttling and locking to ensure that large numbers of jobs do not cause data movement bottlenecks. IFDH is realized as an easy to use layer that users call in their job scripts (e.g. 'ifdh cp'), hiding the low level data movement tools. One advantage of this layer is that the underlying low level tools can be selected or changed without the need for the user to alter their scripts. Logging and performance monitoring can also be added easily. This system will be presented in detail as well as its impact on the ease of data handling at Fermilab experiments.

  6. Water saturation in shaly sands: logging parameters from log-derived values

    International Nuclear Information System (INIS)

    Miyairi, M.; Itoh, T.; Okabe, F.

    1976-01-01

    The methods are presented for determining the relation of porosity to formation factor and that of true resistivity of formation to water saturation, which were investigated through the log interpretation of one of the oil and gas fields of northern Japan Sea. The values of the coefficients ''a'' and ''m'' in porosity-formation factor relation are derived from cross-plot of porosity and resistivity of formation corrected by clay content. The saturation exponent ''n'' is determined from cross-plot of porosity and resistivity index on the assumption that the product of porosity and irreducible water saturation is constant. The relation of porosity to irreducible water saturation is also investigated from core analysis. The new logging parameters determined from the methods, a = 1, m = 2, n = 1.4, improved the values of water saturation by 6 percent in average, and made it easy to distinguish the points which belong to the productive zone and ones belonging to the nonproductive zone

  7. Rill erosion in burned and salvage logged western montane forests: Effects of logging equipment type, traffic level, and slash treatment

    Science.gov (United States)

    Wagenbrenner, J. W.; Robichaud, P. R.; Brown, R. E.

    2016-10-01

    Following wildfires, forest managers often consider salvage logging burned trees to recover monetary value of timber, reduce fuel loads, or to meet other objectives. Relatively little is known about the cumulative hydrologic effects of wildfire and subsequent timber harvest using logging equipment. We used controlled rill experiments in logged and unlogged (control) forests burned at high severity in northern Montana, eastern Washington, and southern British Columbia to quantify rill overland flow and sediment production rates (fluxes) after ground-based salvage logging. We tested different types of logging equipment-feller-bunchers, tracked and wheeled skidders, and wheeled forwarders-as well as traffic levels and the addition of slash to skid trails as a best management practice. Rill experiments were done at each location in the first year after the fire and repeated in subsequent years. Logging was completed in the first or second post-fire year. We found that ground-based logging using heavy equipment compacted soil, reduced soil water repellency, and reduced vegetation cover. Vegetation recovery rates were slower in most logged areas than the controls. Runoff rates were higher in the skidder and forwarder plots than their respective controls in the Montana and Washington sites in the year that logging occurred, and the difference in runoff between the skidder and control plots at the British Columbia site was nearly significant (p = 0.089). Most of the significant increases in runoff in the logged plots persisted for subsequent years. The type of skidder, the addition of slash, and the amount of forwarder traffic did not significantly affect the runoff rates. Across the three sites, rill sediment fluxes were 5-1900% greater in logged plots than the controls in the year of logging, and the increases were significant for all logging treatments except the low use forwarder trails. There was no difference in the first-year sediment fluxes between the feller

  8. Aespoe Hard Rock Laboratory. BIPS logging in borehole KAS09

    International Nuclear Information System (INIS)

    Gustafsson, Jaana; Gustafsson, Christer

    2010-01-01

    This report includes the data gained in BIPS logging performed at the Aespoe Hard Rock Laboratory. The logging operation presented here includes BIPS logging in the core drilled borehole KAS09. The objective for the BIPS logging was to observe the condition of KAS09 in order to restore the borehole in the hydrogeological monitoring programme.All measurements were conducted by Malaa Geoscience AB on October 9th 2009. The objective of the BIPS logging is to achieve information of the borehole including occurrence of rock types as well as determination of fracture distribution and orientation. This report describes the equipment used as well as the measurement procedures and data gained. For the BIPS survey, the result is presented as images. The basic conditions of the BIPS logging for geological mapping and orientation of structures are satisfying for borehole KAS09, although induced affects from the drilling on the borehole walls limit the visibility

  9. Aespoe Hard Rock Laboratory. BIPS logging in borehole KAS09

    Energy Technology Data Exchange (ETDEWEB)

    Gustafsson, Jaana; Gustafsson, Christer (Malaa Geoscience AB (Sweden))

    2010-01-15

    This report includes the data gained in BIPS logging performed at the Aespoe Hard Rock Laboratory. The logging operation presented here includes BIPS logging in the core drilled borehole KAS09. The objective for the BIPS logging was to observe the condition of KAS09 in order to restore the borehole in the hydrogeological monitoring programme.All measurements were conducted by Malaa Geoscience AB on October 9th 2009. The objective of the BIPS logging is to achieve information of the borehole including occurrence of rock types as well as determination of fracture distribution and orientation. This report describes the equipment used as well as the measurement procedures and data gained. For the BIPS survey, the result is presented as images. The basic conditions of the BIPS logging for geological mapping and orientation of structures are satisfying for borehole KAS09, although induced affects from the drilling on the borehole walls limit the visibility

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1980-03-01

    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.

  11. Circular induction accelerator for borehole logging

    International Nuclear Information System (INIS)

    Chen, F.K.; Bertozzi, W.; Corris, G.W.; Diamond, W.; Doucet, J.A.; Schweitzer, J.S.

    1992-01-01

    This patent describes a downhole logging sonde adapted to be moved through a borehole, a source of gamma rays in the sonde for irradiating earth formations traversed by the borehole, one or more gamma ray detectors for detecting gamma rays scattered back to the sonde from the irradiated earth formations, and means for transmitting signals representative of the detected gamma rays to the earth's surface for processing. This patent describes improvement in the gamma ray source comprises a magnetic induction particle accelerator, including: a magnetic circuit having a field magnet, generally circular opposed pole pieces, and a core magnet metal ions from the group consisting of Mn, Zn and Ni; an excitation circuit including a field coil surrounding the field magnet and the core magnet and a core coil surrounding the central axially leg of the core magnet; an annular acceleration chamber interposed between the pole pieces; means for applying time-varying acceleration voltage pulses across the primary excitation circuit; means for injecting charged particles into orbit within the acceleration chamber; means for compressing the particle orbits to trap particles within generally circular orbits within the acceleration chamber; means for generating a particle accelerating magnetic flux in the magnetic circuit; and means for ejecting charged particles from the generally circular orbits and into contact with a target to produce gamma ray photons

  12. Acoustic and Optical Televiewer Borehole Logging

    International Nuclear Information System (INIS)

    Ahmad Hasnulhadi Che Kamaruddin; Nik Marzukee Nik Ibrahim; Zaidi Ibrahim; Nurul Wahida Ahmad Khairuddin; Azmi Ibrahim

    2016-01-01

    This review paper is focused on Borehole Televiewer. Borehole Televiewer or (BHTV) was used to obtain high-resolution acoustical images from the borehole wall. A probe with a high resolution downward looking camera is used. The camera has specific optics (a conical mirror with a ring of bulbs) with just one shot needed to capture the entire borehole circumference as a 360 panoramic view. Settings similar to traditional cameras (exposure, quality, light, frame rate and resolution) make it effective in almost any type of borehole fluid. After each shot, a series of horizontal pixel strings are acquired, giving a rasterized RGB picture in real-time which is transmitted to the console and finally to a monitor. The orientation device embedded in the tool, which is made of 3 inclinometers and 3 magnetometers, allows the inclination and azimuth of the probe to be computed in real-time, correctly orienting the borehole images. Besides, Acoustic and Optical Televiewer has been introduced as its advanced in technological research. Its logging has been successfully applied to geotechnical investigations and mineral exploration (Schepers et al., 2001) due to advances in beam focusing, increased dynamic range, digital recording techniques, and digital data processing (Schepers, 1991). Thus, this paper will go through to the basic principle of (BHTV) as one type of data collection today. (author)

  13. MCNP capabilities for nuclear well logging calculations

    International Nuclear Information System (INIS)

    Forster, R.A.; Little, R.C.; Briesmeister, J.F.; Hendricks, J.S.

    1990-01-01

    The Los Alamos Radiation Transport Code System (LARTCS) consists of state-of-the-art Monte Carlo and discrete ordinates transport codes and data libraries. This paper discusses how the general-purpose continuous-energy Monte Carlo code MCNP (Monte Carlo neutron photon), part of the LARTCS, provides a computational predictive capability for many applications of interest to the nuclear well logging community. The generalized three-dimensional geometry of MCNP is well suited for borehole-tool models. SABRINA, another component of the LARTCS, is a graphics code that can be used to interactively create a complex MCNP geometry. Users can define many source and tally characteristics with standard MCNP features. The time-dependent capability of the code is essential when modeling pulsed sources. Problems with neutrons, photons, and electrons as either single particle or coupled particles can be calculated with MCNP. The physics of neutron and photon transport and interactions is modeled in detail using the latest available cross-section data

  14. Acoustic reflection log in transversely isotropic formations

    Science.gov (United States)

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

    2018-01-01

    We have calculated the waveforms of sonic reflection logging for a fluid-filled borehole located in a transversely isotropic rock. Calculations have been performed for an acoustic impulse source with the characteristic frequency of tens of kilohertz that is considerably less than the frequencies of acoustic borehole imaging tools. It is assumed that the borehole axis coincides with the axis of symmetry of the transversely isotropic rock. It was shown that the reflected wave was excited most efficiently at resonant frequencies. These frequencies are close to the frequencies of oscillations of a fluid column located in an absolutely rigid hollow cylinder. We have shown that the acoustic reverberation is controlled by the acoustic impedance of the rock Z = Vphρs for fixed parameters of the borehole fluid, where Vph is the velocity of horizontally propagating P-wave; ρs is the rock density. The methods of waveform processing to determine the parameters characterizing the reflected wave have been discussed.

  15. Automated recognition of stratigraphic marker shales from geophysical logs in iron ore deposits

    Science.gov (United States)

    Silversides, Katherine; Melkumyan, Arman; Wyman, Derek; Hatherly, Peter

    2015-04-01

    The mining of stratiform ore deposits requires a means of determining the location of stratigraphic boundaries. A variety of geophysical logs may provide the required data but, in the case of banded iron formation hosted iron ore deposits in the Hamersley Ranges of Western Australia, only one geophysical log type (natural gamma) is collected for this purpose. The information from these logs is currently processed by slow manual interpretation. In this paper we present an alternative method of automatically identifying recurring stratigraphic markers in natural gamma logs from multiple drill holes. Our approach is demonstrated using natural gamma geophysical logs that contain features corresponding to the presence of stratigraphically important marker shales. The host stratigraphic sequence is highly consistent throughout the Hamersley and the marker shales can therefore be used to identify the stratigraphic location of the banded iron formation (BIF) or BIF hosted ore. The marker shales are identified using Gaussian Processes (GP) trained by either manual or active learning methods and the results are compared to the existing geological interpretation. The manual method involves the user selecting the signatures for improving the library, whereas the active learning method uses the measure of uncertainty provided by the GP to select specific examples for the user to consider for addition. The results demonstrate that both GP methods can identify a feature, but the active learning approach has several benefits over the manual method. These benefits include greater accuracy in the identified signatures, faster library building, and an objective approach for selecting signatures that includes the full range of signatures across a deposit in the library. When using the active learning method, it was found that the current manual interpretation could be replaced in 78.4% of the holes with an accuracy of 95.7%.

  16. Joint Inversion of Geochemical Data and Geophysical Logs for Lithology Identification in CCSD Main Hole

    Science.gov (United States)

    Deng, Chengxiang; Pan, Heping; Luo, Miao

    2017-12-01

    equations in accordance with the metamorphic formation model and employ BFGS algorithm to minimize the objective function. Finally, we identify lithology according to the composition content which accounts for the largest proportion. The results show that lithology identified by the method of this paper is consistent with core description. Moreover, this method demonstrates the benefits of using oxide content as an adhesive to connect logging data with lithology, can make the metamorphic formation model more understandable and accurate, and avoid selecting complex formation model and building nonlinear logging response equations.

  17. Cost of skid roads for arch logging in West Virginia

    Science.gov (United States)

    George R., Jr. Trimble; Carl R. Barr

    1960-01-01

    In the mountain hardwood country of the northern Appalachians, tree-length skidding with tractor and arch has proved to be economical logging. One essential part of this type of logging is that tree-length logs are winched to the skid roads: tractor and arch do not run around through the woods. Winching distance is commonly 200 to 300 feet; and occasionally an extra...

  18. Western tight gas sands advanced logging workshop proceedings

    Energy Technology Data Exchange (ETDEWEB)

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

    1982-04-01

    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)

  19. An artificial intelligence approach to well log correlation

    International Nuclear Information System (INIS)

    Startzman, R.A.; Kuo, T.B.

    1986-01-01

    This paper shows how an expert computer system was developed to correlate two well logs in at least moderately difficult situations. A four step process was devised to process log trace information and apply a set of rules to identify zonal correlations. Some of the advantages and problems with the artificial intelligence approach are shown using field logs. The approach is useful and, if properly and systematically applied, it can result in good correlations

  20. Towards an entropy-based analysis of log variability

    DEFF Research Database (Denmark)

    Back, Christoffer Olling; Debois, Søren; Slaats, Tijs

    2017-01-01

    the development of hybrid miners: given a (sub-)log, can we determine a priori whether the log is best suited for imperative or declarative mining? We propose using the concept of entropy, commonly used in information theory. We consider different measures for entropy that could be applied and show through...... experimentation on both synthetic and real-life logs that these entropy measures do indeed give insights into the complexity of the log and can act as an indicator of which mining paradigm should be used....

  1. Towards an Entropy-based Analysis of Log Variability

    DEFF Research Database (Denmark)

    Back, Christoffer Olling; Debois, Søren; Slaats, Tijs

    2018-01-01

    the development of hybrid miners: given a log, can we determine a priori whether the log is best suited for imperative or declarative mining? We propose using the concept of entropy, commonly used in information theory. We consider different measures for entropy that could be applied and show through...... experimentation on both synthetic and real-life logs that these entropy measures do indeed give insights into the complexity of the log and can act as an indicator of which mining paradigm should be used....

  2. Real Time Face Quality Assessment for Face Log Generation

    DEFF Research Database (Denmark)

    Kamal, Nasrollahi; Moeslund, Thomas B.

    2009-01-01

    Summarizing a long surveillance video to just a few best quality face images of each subject, a face-log, is of great importance in surveillance systems. Face quality assessment is the back-bone for face log generation and improving the quality assessment makes the face logs more reliable....... Developing a real time face quality assessment system using the most important facial features and employing it for face logs generation are the concerns of this paper. Extensive tests using four databases are carried out to validate the usability of the system....

  3. A legacy of low-impact logging does not elevate prevalence of potentially pathogenic protozoa in free-ranging gorillas and chimpanzees in the Republic of Congo: logging and parasitism in African apes.

    Science.gov (United States)

    Gillespie, Thomas R; Morgan, David; Deutsch, J Charlie; Kuhlenschmidt, Mark S; Salzer, Johanna S; Cameron, Kenneth; Reed, Trish; Sanz, Crickette

    2009-12-01

    Many studies have examined the long-term effects of selective logging on the abundance and diversity of free-ranging primates. Logging is known to reduce the abundance of some primate species through associated hunting and the loss of food trees for frugivores; however, the potential role of pathogens in such primate population declines is largely unexplored. Selective logging results in a suite of alterations in host ecology and forest structure that may alter pathogen dynamics in resident wildlife populations. In addition, environmental pollution with human fecal material may present a risk for wildlife infections with zoonotic protozoa, such as Cryptosporidium and Giardia. To better understand this interplay, we compared patterns of infection with these potentially pathogenic protozoa in sympatric western lowland gorillas (Gorilla gorilla gorilla) and chimpanzees (Pan troglodytes troglodytes) in the undisturbed Goualougo Triangle of Nouabalé-Ndoki National Park and the adjacent previously logged Kabo Concession in northern Republic of Congo. No Cryptosporidium infections were detected in any of the apes examined and prevalence of infection with Giardia was low (3.73% overall) and did not differ between logged and undisturbed forest for chimpanzees or gorillas. These results provide a baseline for prevalence of these protozoa in forest-dwelling African apes and suggest that low-intensity logging may not result in long-term elevated prevalence of potentially pathogenic protozoa.

  4. Systematic logging utilizing a log sheet designed for drill core descriptions. An example in uranium exploration activities

    International Nuclear Information System (INIS)

    Sasao, Eiji; Tsuruta, Tadahiko; Iida, Yoshimasa

    2000-01-01

    We describe the log sheets used during uranium exploration activities for unconformity-related uranium deposits by JNC. The purpose of using the logging sheets is to standardize the objects which all geologists must observe and for data quality assurance. The log sheets are a three-part set describing basement lithology, sandstone lithology and geotechnics. We devised our own log sheets to describe both the sandstone and the underlying basement rock when we started exploration in Athabasca Basin, Canada. We modified the sheets to gain a better understanding of the geological features related to uranium mineralization, and made final improvements to satisfy required quality based on the criteria of descriptive objects and accuracy. Use of the log sheets resulted in effective performance of core logging and improvement in the display of data. (author)

  5. Urban Geocaching: what Happened in Lisbon during the Last Decade?

    Science.gov (United States)

    Nogueira Mendes, R.; Rodrigues, T.; Rodrigues, A. M.

    2013-05-01

    Created in 2000 in the United States of America, Geocaching has become a major phenomenon all around the world, counting actually with millions of Geocaches (or caches) that work as a recreational motivation for millions of users, called Geocachers. During the last 30 days over 5,000,000 new logs have been submitted worldwide, disseminating individual experiences, motivations, emotions and photos through the official Geocaching website (www.geocaching.com), and several official or informal national web forums. The activity itself can be compared with modern treasure hunting that uses handheld GPS, Smartphones or Tablets, WEB 2.0, wiki features and technologies to keep Geocachers engaged with their activity, in a strong social-network. All these characteristics make Geocaching an activity with a strong geographic component that deals closely with the surrounding environment where each cache has been hidden. From previous work, significance correlation has been found regarding hides and natural/rural environments, but metropolitan and urban areas like Lisbon municipality (that holds 3.23% of the total 27534 Portuguese caches), still registers the higher density of Geocaches, and logs numbers. Lacking "natural/rural" environment, Geocaching in cities tend to happen in symbolic areas, like public parks and places, sightseeing spots and historical neighborhoods. The present study looks to Geocaching within the city of Lisbon, in order to understand how it works, and if this activity reflects the city itself, promoting its image and cultural heritage. From a freely available dataset that includes all Geocaches that have been placed in Lisbon since February 2001, spatial analysis has been conducted, showing the informal preferences of this activity. Results show a non-random distribution of caches within the study area, similar to the land use distribution. Preferable locations tend to be in iconic places of the city, usually close to the Tagus River, that concentrates 25

  6. Static dictionaries on AC0 RAMs: query time (√log n/log log n) is necessary and sufficient

    DEFF Research Database (Denmark)

    Andersson, Arne; Miltersen, Peter Bro; Riis, Søren

    1996-01-01

    ) on the time for answering membership queries in a set of size n when reasonable space is used for the data structure storing the set; the upper bound can be obtained using O(n) space, and the lower bound holds even if we allow space 2polylog n. Several variations of this result are also obtained. Among others......, we show a tradeoff between time and circuit depth under the unit-cost assumption: any RAM instruction set which permits a linear space, constant query time solution to the static dictionary problem must have an instruction of depth Ω(log w/log log to), where w is the word size of the machine (and log...

  7. Fermi's Paradox - The Last Challenge For Copernicanism?

    Directory of Open Access Journals (Sweden)

    Ćirković, M. M.

    2009-06-01

    Full Text Available We review Fermi's paradox (or the "Great Silence" problem, not only arguably the oldest and crucial problem for the Search for ExtraTerrestrial Intelligence (SETI, but also a conundrum of profound scientific, philosophical and cultural importance. By a simple analysis of observation selection effects, the correct resolution of Fermi's paradox is certain to tell us something about the future of humanity. Already more than three quarters of century old puzzle -- and a quarter of century since the last major review paper in the field by G. David Brin -- has generated many ingenious discussions and hypotheses. We analyze the often tacit methodological assumptions built in various answers to this puzzle and attempt a new classification of the numerous solutions proposed in an already huge literatureon the subject. Finally, we consider the ramifications of variousclasses of hypotheses for the practical SETI projects. Somewhatparadoxically, it seems that the class of (neocatastrophichypotheses gives, on the balance, the strongest justification tooptimism regarding our current and near-future SETI efforts.

  8. Fermi's paradox: The last challenge for copernicanism?

    Directory of Open Access Journals (Sweden)

    Ćirković M.M.

    2009-01-01

    Full Text Available We review Fermi's paradox (or the 'Great Silence' problem, not only arguably the oldest and crucial problem for the Search for ExtraTerrestrial Intelligence (SETI, but also a conundrum of profound scientific, philosophical and cultural importance. By a simple analysis of observation selection effects, the correct resolution of Fermi's paradox is certain to tell us something about the future of humanity. Already more than three quarters of century old puzzle and a quarter of century since the last major review paper in the field by G. David Brin has generated many ingenious discussions and hypotheses. We analyze the often tacit methodological assumptions built in various answers to this puzzle and attempt a new classification of the numerous solutions proposed in an already huge literature on the subject. Finally, we consider the ramifications of various classes of hypotheses for the practical SETI projects. Somewhat paradoxically, it seems that the class of (neocatastrophic hypotheses gives, on the balance, the strongest justification to optimism regarding our current and near-future SETI efforts.

  9. Condition and fate of logged forests in the Brazilian Amazon.

    Science.gov (United States)

    Gregory P. Asner; Eben N. Broadbent; Paulo J. C. Oliveira; Michael Keller; David E. Knapp; Jose N. M. Silva

    2006-01-01

    The long-term viability of a forest industry in the Amazon region of Brazil depends on the maintenance of adequate timber volume and growth in healthy forests. Using extensive high-resolution satellite analyses, we studied the forest damage caused by recent logging operations and the likelihood that logged forests would be cleared within 4 years after timber harvest....

  10. Teaching an Old Log New Tricks with Machine Learning.

    Science.gov (United States)

    Schnell, Krista; Puri, Colin; Mahler, Paul; Dukatz, Carl

    2014-03-01

    To most people, the log file would not be considered an exciting area in technology today. However, these relatively benign, slowly growing data sources can drive large business transformations when combined with modern-day analytics. Accenture Technology Labs has built a new framework that helps to expand existing vendor solutions to create new methods of gaining insights from these benevolent information springs. This framework provides a systematic and effective machine-learning mechanism to understand, analyze, and visualize heterogeneous log files. These techniques enable an automated approach to analyzing log content in real time, learning relevant behaviors, and creating actionable insights applicable in traditionally reactive situations. Using this approach, companies can now tap into a wealth of knowledge residing in log file data that is currently being collected but underutilized because of its overwhelming variety and volume. By using log files as an important data input into the larger enterprise data supply chain, businesses have the opportunity to enhance their current operational log management solution and generate entirely new business insights-no longer limited to the realm of reactive IT management, but extending from proactive product improvement to defense from attacks. As we will discuss, this solution has immediate relevance in the telecommunications and security industries. However, the most forward-looking companies can take it even further. How? By thinking beyond the log file and applying the same machine-learning framework to other log file use cases (including logistics, social media, and consumer behavior) and any other transactional data source.

  11. The log-linear return approximation, bubbles, and predictability

    DEFF Research Database (Denmark)

    Engsted, Tom; Pedersen, Thomas Quistgaard; Tanggaard, Carsten

    We study in detail the log-linear return approximation introduced by Campbell and Shiller (1988a). First, we derive an upper bound for the mean approximation error, given stationarity of the log dividendprice ratio. Next, we simulate various rational bubbles which have explosive conditional expec...

  12. The Log-Linear Return Approximation, Bubbles, and Predictability

    DEFF Research Database (Denmark)

    Engsted, Tom; Pedersen, Thomas Quistgaard; Tanggaard, Carsten

    2012-01-01

    We study in detail the log-linear return approximation introduced by Campbell and Shiller (1988a). First, we derive an upper bound for the mean approximation error, given stationarity of the log dividend-price ratio. Next, we simulate various rational bubbles which have explosive conditional expe...

  13. Predictive models of forest logging residues of Triplochiton ...

    African Journals Online (AJOL)

    The model developed indicated that logarithmic functions performed better than other form of equation. The findings of this study revealed that there is significant logging residues left to waste in the forest after timber harvest and quantifying this logging residue in terms of biomass model can serve as management tools in ...

  14. Secure Audit Logging with Tamper-Resistant Hardware

    NARCIS (Netherlands)

    Chong, C.N.; Peng, Z.; Peng, Z.; Hartel, Pieter H.; Gritzalis, D.; De Capitani di Vimercati, S.; Katsikas, S.K.; Samarati, P.

    Secure perimeter schemes (e.g. DRM) and tracing traitor schemes (e.g. watermarking, audit logging) strive to mitigate the problems of content escaping the control of the rights holder. Secure audit logging records the user's actions on content and enables detection of some forms of tampering with

  15. Ubiquitous Learning Project Using Life-Logging Technology in Japan

    Science.gov (United States)

    Ogata, Hiroaki; Hou, Bin; Li, Mengmeng; Uosaki, Noriko; Mouri, Kosuke; Liu, Songran

    2014-01-01

    A Ubiquitous Learning Log (ULL) is defined as a digital record of what a learner has learned in daily life using ubiquitous computing technologies. In this paper, a project which developed a system called SCROLL (System for Capturing and Reusing Of Learning Log) is presented. The aim of developing SCROLL is to help learners record, organize,…

  16. 14 CFR 125.407 - Maintenance log: Airplanes.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Maintenance log: Airplanes. 125.407 Section... OPERATIONS: AIRPLANES HAVING A SEATING CAPACITY OF 20 OR MORE PASSENGERS OR A MAXIMUM PAYLOAD CAPACITY OF 6... Maintenance log: Airplanes. (a) Each person who takes corrective action or defers action concerning a reported...

  17. Ontology-driven extraction of event logs from relational databases

    NARCIS (Netherlands)

    Calvanese, Diego; Montali, Marco; Syamsiyah, Alifah; van der Aalst, Wil M P; Reichert, M.; Reijers, H.A.

    2015-01-01

    Process mining is an emerging discipline whose aim is to discover, monitor and improve real processes by extracting knowledge from event logs representing actual process executions in a given organizational setting. In this light, it can be applied only if faithful event logs, adhering to accepted

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

    Science.gov (United States)

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

    2012-01-01

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

  19. Log-periodic dipole antenna with low cross-polarization

    DEFF Research Database (Denmark)

    Pivnenko, Sergey

    2006-01-01

    In this work, log-periodic antennas with improved cross-polarization level were studied. It was found that some modifications of the traditional design lead to an essential improvement of the co-to-cross polarization ratio up to 40 dB. An improved design of a log-periodic dipole antenna with low...

  20. The analog CTS communication interface in nuclear logging

    International Nuclear Information System (INIS)

    Li Min

    2000-01-01

    The author introduced a micro-controller-based CTS communication interface in nuclear logging, which provided convenience for the overhaul and regulation of the logging tool in CTS communication system. The use of micro-controller simplified the hardware structure of the interface, made the soft structure more rational and the whole system more flexible to control

  1. 21 CFR 211.182 - Equipment cleaning and use log.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Equipment cleaning and use log. 211.182 Section 211.182 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Reports § 211.182 Equipment cleaning and use log. A written record of major equipment cleaning...

  2. Logging residues under different stand and harvesting conditions, Rocky Mountains

    Science.gov (United States)

    Robert E. Benson; Cameron M. Johnston

    1976-01-01

    Volume and characteristics of logging residues from 34 harvest areas are presented. Clearcuts and partial cuts logged to conventional utilization levels and to close utilization levels are included. Residue volumes ranged from almost 3, 600 ft3 /acre of wood 3-inches-plus down to about 550 ft3 /acre, depending on treatment. More than 60 percent of the residues were...

  3. Effect of logging wounds on diameter growth of sawlog-size Appalachian hardwood crop trees

    Science.gov (United States)

    Neil I. Lamson; H. Clay Smith; H. Clay Smith

    1988-01-01

    In previously thinned, even-aged Appalachian hardwood stands, 5-year diameter growth of 102 wounded and 102 unwounded codominant crop trees were compared. A wounded crop tre was defined as one with at least one exposed sapwood logging wound at least 100 inch2 in size. An unwounded crop tree of the same species and size was selected near each of the 102 wounded trees....

  4. Analyzing engagement in a web-based intervention platform through visualizing log-data.

    Science.gov (United States)

    Morrison, Cecily; Doherty, Gavin

    2014-11-13

    Engagement has emerged as a significant cross-cutting concern within the development of Web-based interventions. There have been calls to institute a more rigorous approach to the design of Web-based interventions, to increase both the quantity and quality of engagement. One approach would be to use log-data to better understand the process of engagement and patterns of use. However, an important challenge lies in organizing log-data for productive analysis. Our aim was to conduct an initial exploration of the use of visualizations of log-data to enhance understanding of engagement with Web-based interventions. We applied exploratory sequential data analysis to highlight sequential aspects of the log data, such as time or module number, to provide insights into engagement. After applying a number of processing steps, a range of visualizations were generated from the log-data. We then examined the usefulness of these visualizations for understanding the engagement of individual users and the engagement of cohorts of users. The visualizations created are illustrated with two datasets drawn from studies using the SilverCloud Platform: (1) a small, detailed dataset with interviews (n=19) and (2) a large dataset (n=326) with 44,838 logged events. We present four exploratory visualizations of user engagement with a Web-based intervention, including Navigation Graph, Stripe Graph, Start-Finish Graph, and Next Action Heat Map. The first represents individual usage and the last three, specific aspects of cohort usage. We provide examples of each with a discussion of salient features. Log-data analysis through data visualization is an alternative way of exploring user engagement with Web-based interventions, which can yield different insights than more commonly used summative measures. We describe how understanding the process of engagement through visualizations can support the development and evaluation of Web-based interventions. Specifically, we show how visualizations

  5. Inversion of a lateral log using neural networks

    International Nuclear Information System (INIS)

    Garcia, G.; Whitman, W.W.

    1992-01-01

    In this paper a technique using neural networks is demonstrated for the inversion of a lateral log. The lateral log is simulated by a finite difference method which in turn is used as an input to a backpropagation neural network. An initial guess earth model is generated from the neural network, which is then input to a Marquardt inversion. The neural network reacts to gross and subtle data features in actual logs and produces a response inferred from the knowledge stored in the network during a training process. The neural network inversion of lateral logs is tested on synthetic and field data. Tests using field data resulted in a final earth model whose simulated lateral is in good agreement with the actual log data

  6. Cased-hole log analysis and reservoir performance monitoring

    CERN Document Server

    Bateman, Richard M

    2015-01-01

    This book addresses vital issues, such as the evaluation of shale gas reservoirs and their production. Topics include the cased-hole logging environment, reservoir fluid properties; flow regimes; temperature, noise, cement bond, and pulsed neutron logging; and casing inspection. Production logging charts and tables are included in the appendices. The work serves as a comprehensive reference for production engineers with upstream E&P companies, well logging service company employees, university students, and petroleum industry training professionals. This book also: ·       Provides methods of conveying production logging tools along horizontal well segments as well as measurements of formation electrical resistivity through casing ·       Covers new information on fluid flow characteristics in inclined pipe and provides new and improved nuclear tool measurements in cased wells ·       Includes updates on cased-hole wireline formation testing  

  7. Toward an Automated Labeling of Event Log Attributes

    DEFF Research Database (Denmark)

    Abbad Andaloussi, Amine; Burattin, Andrea; Weber, Barbara

    2018-01-01

    information systems often do not comply with the required maturity level, since they lack the notion of process instance, also referred in process mining as “case id”. Without a proper identification of the case id attribute in log files, the outcome of process mining algorithms is unpredictable. This paper...... proposes a new approach that aims to overcome this challenge by automatically inferring the case id attribute from log files. The approach has been implemented as a ProM plugin and evaluated with several real-world event logs. The results demonstrate a high accuracy in inferring the case id attribute.......Process mining aims at exploring the data produced by executable business processes to mine the underlying control-flow and dataflow. Most of the process mining algorithms assume the existence of an event log with a certain maturity level. Unfortunately, the logs provided by process unaware...

  8. Rock mass characterization for Copenhagen Metro using face logs

    DEFF Research Database (Denmark)

    Hansen, Sanne Louise; Galsgaard, Jens; Foged, Niels Nielsen

    2015-01-01

    An extension of the existing Metro in central Copenhagen is currently under construction. We present a comparison of the different field logging techniques available from a large number of borehole logs and face logs carried out during the construction in cooperation with the constructor and client......, describing rock mass characteristics using detailed face logging with geological description and recording of induration and fracturing, giving a field RQD value during excavation, combined with televiewer logs, when available, has shown to be a valuable tool for rock mass characterization compared......’s representatives, which illustrate and approve the applied methods. The new ‘Cityringen’ Metro will consist of two 16 km single track tunnels, with 17 stations and 3 construction and ventilation shafts. The geological ground conditions are dominated by glacial and postglacial deposits overlying Paleocene Greensand...

  9. PRODUCTION PROGRAM OPTIMIZATION – RESPONSIBLE MANAGEMENT METHOD OF LOGGING

    Directory of Open Access Journals (Sweden)

    Severian Vlăduț IACOB

    2014-06-01

    Full Text Available Aggression of any kind on the environment and especially uncontrolled exploitation of forests has generated mixed reaction among the public and politicians, but especially in the academic sphere where actually were fired early warning signs of the effects of these actions. Reduction of Earth's forested areas was discussed by specialists as continuous and highly accelerated, especially in the last century when reserve "green gold" of mankind has halved. As a result, the conservation of forests and prevention of environmental degradation have become great concerns of each nation, but the need for global action required the transformation into strategic objectives of regional and international bodies. They have designed policies and measures generally available and have created favorable framework implementation in the Member States and beyond. One of the projects that came to life and expanded worldwide was the sustainable development today, basically there are no area where the activity is not subrogated to achieve a balance between the components of economic, social and environmental. From this perspective forestry and forestry exploitation is the place where really have achieved sustainability. Achieving this requirement becomes an obligation, both for woodland owners and operators seeking to obtain profit from logging. Compliance and ensuring responsible management are certainly prerequisites of sustainability in this sector. Scientific planning of production is a method of management responsible. This study takes into account, on the one hand, highlighting the effects generated by uncontrolled deforestation and the importance of sustainable forest exploitation, and on the other hand, presenting the need to use scientific methods to practice responsible management.

  10. Log-concavity property for some well-known distributions

    Directory of Open Access Journals (Sweden)

    G. R. Mohtashami Borzadaran

    2011-12-01

    Full Text Available Interesting properties and propositions, in many branches of science such as economics have been obtained according to the property of cumulative distribution function of a random variable as a concave function. Caplin and Nalebuff (1988,1989, Bagnoli and Khanna (1989 and Bagnoli and Bergstrom (1989 , 1989, 2005 have discussed the log-concavity property of probability distributions and their applications, especially in economics. Log-concavity concerns twice differentiable real-valued function g whose domain is an interval on extended real line. g as a function is said to be log-concave on the interval (a,b if the function ln(g is a concave function on (a,b. Log-concavity of g on (a,b is equivalent to g'/g being monotone decreasing on (a,b or (ln(g" 6] have obtained log-concavity for distributions such as normal, logistic, extreme-value, exponential, Laplace, Weibull, power function, uniform, gamma, beta, Pareto, log-normal, Student's t, Cauchy and F distributions. We have discussed and introduced the continuous versions of the Pearson family, also found the log-concavity for this family in general cases, and then obtained the log-concavity property for each distribution that is a member of Pearson family. For the Burr family these cases have been calculated, even for each distribution that belongs to Burr family. Also, log-concavity results for distributions such as generalized gamma distributions, Feller-Pareto distributions, generalized Inverse Gaussian distributions and generalized Log-normal distributions have been obtained.

  11. Influence of borehole-eccentred tools on wireline and logging-while-drilling sonic logging measurements

    KAUST Repository

    Pardo, David

    2013-02-13

    We describe a numerical study to quantify the influence of tool-eccentricity on wireline (WL) and logging-while-drilling (LWD) sonic logging measurements. Simulations are performed with a height-polynomial-adaptive (hp) Fourier finite-element method that delivers highly accurate solutions of linear visco-elasto-acoustic problems in the frequency domain. The analysis focuses on WL instruments equipped with monopole or dipole sources and LWD instruments with monopole excitation. Analysis of the main propagation modes obtained from frequency dispersion curves indicates that the additional high-order modes arising as a result of borehole-eccentricity interfere with the main modes (i.e., Stoneley, pseudo-Rayleigh and flexural). This often modifies (decreases) the estimation of shear and compressional formation velocities, which should be corrected (increased) to account for borehole-eccentricity effects. Undesired interferences between different modes can occur at different frequencies depending upon the properties of the formation and fluid annulus size, which may difficult the estimation of the formation velocities. © 2013 European Association of Geoscientists & Engineers.

  12. Lithologic log and interpretation of instrument logs NURE project, Carson Sink, Nevada, borehole

    International Nuclear Information System (INIS)

    Horton, R.C.

    1978-04-01

    No uranium mineralization was penetrated by the drilling. The uranium content of the rock units are within the usual range for unmineralized rocks of the types penetrated. Although the instrument logs indicated ample porosity in the sedimentary section, drill-stem tests in the intervals 699 to 722 ft, 3,692 to 3,734 ft, and 3,920 to 3,995 ft failed to recover any formation fluid. The instrument logs generally indicated low porosity and permeability in the volcanic rocks. The low permeability may have prohibited the circulation of ground water and possible supergene enrichment. The Carson Sink is a closed basin and all water is lost by evaporation, although there may be minor subsurface interbasin transfer. As the basin subsided dense connate water (brines) may have been trapped within the sediments making circulation of less dense water impossible. At present, nonsaline water is found only at shallow depths and is underlain by saline water. The hydrologic regime of the basin is complex and general assumptions should be made with care. Detailed analysis of hydrologic data may reveal zones of deep circulation. Reducing conditions, as evidenced by thin beds of organic rich material and pyrite, are present at depth. However, the unconsolidated sediments are young (Pleistocene to Recent) and perhaps too youthful for substantial mineralization to have occurred. No further deep drilling is recommended until the complex prehistoric hydrologic regime is studied. The study should include the geologic structural history of the basin and influence of Pleistocene and earlier pluvial cycles

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

    Science.gov (United States)

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

    2011-09-16

    A previously reported chromatographic method to determine the 1-octanol/water partition coefficient (log P(o/w)) of organic compounds is used to estimate the hydrophobicity of bases, mainly commercial drugs with diverse chemical nature and pK(a) values higher than 9. For that reason, mobile phases buffered at high pH to avoid the ionization of the solutes and three different columns (Phenomenex Gemini NX, Waters XTerra RP-18 and Waters XTerra MS C(18)) with appropriate alkaline-resistant stationary phases have been used. Non-ionizable substances studied in previous works were also included in the set of compounds to evaluate the consistency of the method. The results showed that all the columns provide good estimations of the log P(o/w) for most of the compounds included in this study. The Gemini NX column has been selected to calculate log P(o/w) values of the set of studied drugs, and really good correlations between the determined log P(o/w) values and those considered as reference were obtained, proving the ability of the procedure for the lipophilicity assessment of bioactive compounds with very different structures and functionalities. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Review of the Czubek--Jonas gamma-log program

    International Nuclear Information System (INIS)

    Matthews, M.

    1978-11-01

    Several gamma-ray logs were computer processed using the Czubek--Jones and DOE's MDDAT gamma-log programs. Both of these programs convert counts per second from the gamma-ray logs to percent eU 3 O 8 . The results of these programs were compared to each other and to the core analysis (percent U 3 O 8 ) of the logged boreholes. The two gamma-log programs produced similar results. The core analysis did not compare favorably with the results of either gamma-log program. This unfavorable comparison is probably due to an incorrect assumption of secular equilibrium for the ore surrounding the boreholes. The Czubek--Jonas program requires a knowledge of the linear attenuation coefficient of the rocks surrounding a borehole. This limits the usefulness of the program because this coefficient is generally not known and varies for different gamma-ray energies. It is recommended that the MDDAT program continue to be used for estimating the grade (percent eU 3 O 8 ) from gamma-log data and not be replaced by the Czubek--Jonas program

  15. Dual detector neutron lifetime log: theory and practical applications

    International Nuclear Information System (INIS)

    Serpas, C.J.; Wichmann, P.A.; Fertl, W.H.; DeVries, M.R.; Rndall, R.R.

    1977-01-01

    The Neutron Lifetime Log instrumentation has continued to evolve and now is equipped with dual detectors for increased ease in gas detection and also a ratio response for a simultaneous porosity determination. A good deal of experimentation was involved to minimize both lithology and salinity effects on the porosity indication. This paper contains a discussion of the theory and concepts related to the application of the Dual Detector Neutron Lifetime Log (DNLL). It is important to note that with these advances the recording of thermal neutron capture cross section (Σ) remains consistent with the past measurements of earlier generations of instruments as the most accurate determination of this parameter. A number of field examples of the newly logged results are shown. These field cases include Dual Detector NLL's run thru the drill strings of highly deviated holes when difficulties were encountered in getting conventional open hole logs to bottom, logs thru open perforations and hot radioactive zones, comparisons of the large and small diameter instruments, logs with anomalous fluids in the annulus, logs thru multiple casing strings, and a number of other examples

  16. Numerical simulation of responses for cased-hole density logging

    International Nuclear Information System (INIS)

    Wu, Wensheng; Fu, Yaping; Niu, Wei

    2013-01-01

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

  17. Extracting the Textual and Temporal Structure of Supercomputing Logs

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-05-26

    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.

  18. Construction and validation of a Tamil logMAR chart.

    Science.gov (United States)

    Varadharajan, Srinivasa; Srinivasan, Krithica; Kumaresan, Brindha

    2009-09-01

    To design, construct and validate a new Tamil logMAR visual acuity chart based on current recommendations. Ten Tamil letters of equal legibility were identified experimentally and were used in the chart. Two charts, one internally illuminated and one externally illuminated, were constructed for testing at 4 m distance. The repeatability of the two charts was tested. For validation, the two charts were compared with a standard English logMAR chart (ETDRS). When compared to the ETDRS chart, a difference of 0.06 +/- 0.07 and 0.07 +/- 0.07 logMAR was found for the internally and externally illuminated charts respectively. Limits of agreement between the internally illuminated Tamil logMAR chart and ETDRS chart were found to be (-0.08, 0.19), and (-0.07, 0.20) for the externally illuminated chart. The test - retest results showed a difference of 0.02 +/- 0.04 and 0.02 +/- 0.06 logMAR for the internally and externally illuminated charts respectively. Limits of agreement for repeated measurements for the internally illuminated Tamil logMAR chart were found to be (-0.06, 0.10), and (-0.10, 0.14) for the externally illuminated chart. The newly constructed Tamil logMAR charts have good repeatability. The difference in visual acuity scores between the newly constructed Tamil logMAR chart and the standard English logMAR chart was within acceptable limits. This new chart can be used for measuring visual acuity in the literate Tamil population.

  19. The last LHC dipole magnet is lowered

    CERN Multimedia

    Claudia Marcelloni

    2007-01-01

    A ceremony is held as the last of 1746 superconducting magnets is lowered into the 27-km circumference tunnel that houses the LHC. The LHC project leader, Lyn Evans, changes a banner reading ‘first magnet for the LHC’ to ‘last magnet for the LHC’ in his native Welsh.

  20. Determination of residual oil saturation from time-lapse pulsed neutron capture logs in a large sandstone reservoir

    International Nuclear Information System (INIS)

    Syed, E.V.; Salaita, G.N.; McCaffery, F.G.

    1991-01-01

    Cased hole logging with pulsed neutron tools finds extensive use for identifying zones of water breakthrough and monitoring oil-water contacts in oil reservoirs being depleted by waterflooding or natural water drive. Results of such surveys then find direct use for planning recompletions and water shutoff treatments. Pulsed neutron capture (PNC) logs are useful for estimating water saturation changes behind casing in the presence of a constant, high-salinity environment. PNC log surveys run at different times, i.e., in a time-lapse mode, are particularly amenable to quantitative analysis. The combined use of the original open hole and PNC time-lapse log information can then provide information on remaining or residual oil saturations in a reservoir. This paper reports analyses of historical pulsed neutron capture log data to assess residual oil saturation in naturally water-swept zones for selected wells from a large sandstone reservoir in the Middle East. Quantitative determination of oil saturations was aided by PNC log information obtained from a series of tests conducted in a new well in the same field

  1. Geothermal well log interpretation state of the art. Final report

    Energy Technology Data Exchange (ETDEWEB)

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

    1980-01-01

    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.

  2. Application of computer data processing of well logging in Azerbaijan

    International Nuclear Information System (INIS)

    Vorob'ev, Yu.A.; Shilov, G.Ya.; Samedova, A.S.

    1989-01-01

    Transition from the mannal quantitative interpretation of materials of well-logging study (WLS) to application of computer in production association (PA) Azneftegeologiya is described. WLS materials were processed manually in PA till 1986. Later on interpretation was conducted with the use of computer in order to determine clayiness, porosity, oil and gas saturation, fluid of strata. Examples of presentation of results of computer interpretation of WLS data (including gamma-logging and neutron-gamma-logging) for determining porosity and oil saturation of sandy mudrocks are given

  3. Screening efficacy of a simplified logMAR chart

    Directory of Open Access Journals (Sweden)

    Naganathan Muthuramalingam

    2016-04-01

    Aim: This study evaluates the efficacy of a simplified logMAR chart, designed for VA testing over the conventional Snellen chart, in a school-based vision-screening programme. Methods: We designed a simplified logMAR chart by employing the principles of the Early Treatment Diabetic Retinopathy Study (ETDRS chart in terms of logarithmic letter size progression, inter-letter spacing, and inter-line spacing. Once the simplified logMAR chart was validated by students in the Elite school vision-screening programme, we set out to test the chart in 88 primary and middle schools in the Tiruporur block of Kancheepuram district in Tamil Nadu. One school teacher in each school was trained to screen a cross-sectional population of 10 354 primary and secondary school children (girls: 5488; boys: 4866 for VA deficits using a new, simplified logMAR algorithm. An experienced paediatric optometrist was recruited to validate the screening methods and technique used by the teachers to collect the data. Results: The optometrist screened a subset of 1300 school children from the total sample. The optometrist provided the professional insights needed to validate the clinical efficacy of the simplified logMAR algorithm and verified the reliability of the data collected by the teachers. The mean age of children sampled for validation was 8.6 years (range: 9–14 years. The sensitivity and the specificity of the simplified logMAR chart when compared to the standard logMAR chart were found to be 95% and 98%, respectively. Kappa value was 0.97. Sensitivity of the teachers’ screening was 66.63% (95% confidence interval [CI]: 52.73–77.02 and the specificity was 98.33% (95% CI: 97.49–98.95. Testing of VA was done under substandard illumination levels in 87% of the population. A total of 10 354 children were screened, 425 of whom were found to have some form of visual and/or ocular defect that was identified by the teacher or optometrist. Conclusion: The simplified logMAR testing algorithm

  4. Perfil logístico del sector cemento en Colombia

    OpenAIRE

    Hernández Calderón, Miguel Ángel; Nieves de la Hoz, Celia Elena

    2015-01-01

    Este proyecto caracteriza la logística del sector cemento en Colombia al identificar y describir los principales actores, procesos y materiales involucrados en la cadena de suministros del sector. Este documento compila la información logística relevante para la producción de cemento en Colombia. Esta información se obtuvo sintetizando estudios y reportes acerca de las prácticas logísticas y las condiciones en las que éstas se desarrollan. Adicionalmente se realizaron visitas empresariales en...

  5. Development of interpretation models for PFN uranium log analysis

    International Nuclear Information System (INIS)

    Barnard, R.W.

    1980-11-01

    This report presents the models for interpretation of borehole logs for the PFN (Prompt Fission Neutron) uranium logging system. Two models have been developed, the counts-ratio model and the counts/dieaway model. Both are empirically developed, but can be related to the theoretical bases for PFN analysis. The models try to correct for the effects of external factors (such as probe or formation parameters) in the calculation of uranium grade. The theoretical bases and calculational techniques for estimating uranium concentration from raw PFN data and other parameters are discussed. Examples and discussions of borehole logs are included

  6. Nuclear cross section library for oil well logging analysis

    International Nuclear Information System (INIS)

    Kodeli, I.; Kitsos, S.; Aldama, D.L.; Zefran, B.

    2003-01-01

    As part of the IRTMBA (Improved Radiation Transport Modelling for Borehole Applications) Project of the EU Community's 5 th Programme a special purpose multigroup cross section library to be used in the deterministic (as well as Monte Carlo) oil well logging particle transport calculations was prepared. This library is expected to improve the prediction of the neutron and gamma spectra at the detector positions of the logging tool, and their use for the interpretation of the neutron logging measurements was studied. Preparation and testing of this library is described. (author)

  7. Physical and measuring principles of nuclear well logging techniques

    International Nuclear Information System (INIS)

    Loetzsch, U.; Winkler, R.

    1981-01-01

    Proceeding from the general task of nuclear geophysics as a special discipline of applied geophyscis, the essential physical problems of nuclear well logging techniques are considered. Particularly, the quantitative relationship between measured values and interesting geologic parameters to be determined are discussed taking into account internal and external perturbation parameters. Resulting from this study, the technological requirements for radiation sources and their shielding, for detectors, electronic circuits in logging tools, signal transmission by cable and recording equipment are derived, and explained on the basis of examples of gamma-gamma and neutron-neutron logging. (author)

  8. Responses of soil fungi to logging and oil palm agriculture in Southeast Asian tropical forests.

    Science.gov (United States)

    McGuire, K L; D'Angelo, H; Brearley, F Q; Gedallovich, S M; Babar, N; Yang, N; Gillikin, C M; Gradoville, R; Bateman, C; Turner, B L; Mansor, P; Leff, J W; Fierer, N

    2015-05-01

    Human land use alters soil microbial composition and function in a variety of systems, although few comparable studies have been done in tropical forests and tropical agricultural production areas. Logging and the expansion of oil palm agriculture are two of the most significant drivers of tropical deforestation, and the latter is most prevalent in Southeast Asia. The aim of this study was to compare soil fungal communities from three sites in Malaysia that represent three of the most dominant land-use types in the Southeast Asia tropics: a primary forest, a regenerating forest that had been selectively logged 50 years previously, and a 25-year-old oil palm plantation. Soil cores were collected from three replicate plots at each site, and fungal communities were sequenced using the Illumina platform. Extracellular enzyme assays were assessed as a proxy for soil microbial function. We found that fungal communities were distinct across all sites, although fungal composition in the regenerating forest was more similar to the primary forest than either forest community was to the oil palm site. Ectomycorrhizal fungi, which are important associates of the dominant Dipterocarpaceae tree family in this region, were compositionally distinct across forests, but were nearly absent from oil palm soils. Extracellular enzyme assays indicated that the soil ecosystem in oil palm plantations experienced altered nutrient cycling dynamics, but there were few differences between regenerating and primary forest soils. Together, these results show that logging and the replacement of primary forest with oil palm plantations alter fungal community and function, although forests regenerating from logging had more similarities with primary forests in terms of fungal composition and nutrient cycling potential. Since oil palm agriculture is currently the mostly rapidly expanding equatorial crop and logging is pervasive across tropical ecosystems, these findings may have broad applicability.

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

    Directory of Open Access Journals (Sweden)

    Hudson Judith N

    2012-11-01

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

  10. New roles of LWD and wireline logging in scientific ocean drilling

    Science.gov (United States)

    Sanada, Y.; Kido, Y. N.; Moe, K.; Aoike, K.

    2014-12-01

    D/V Chikyu implemented by CDEX/JAMSTEC joined IODP from 2007. Various LWD (Logging While Drilling) and wireline logging have been carried out in many expeditions and for various purposes. Significant features of logging in Chikyu expeditions are many use of LWD than wireline logging, and riser dirlling. riser selected specific tools for each scientific target, and 3) carried out various borehole experiments. LWD has been more popular than wireline logging in Chikyu expeditions, because its advantages match theirs science targets. The advantages are followings. 1) LWD has more opportunities for measurement in unstable borehole, such as in the series of Nankai trough drilling expeditions. 2) LWD realtime data allows us to make realtime interpretation and operational decision. Realtime interpretation was required to set obsevartory at the properposition. 3) LWD before coring allows us to make a strategy of spot coring.We can design coring intervals for our interest and core length to improve core recovery.Riser drilling brings us merits for logging. One is hole stability (good hole condition) and the other is the use of large diameter tools. Controled drilling mud in riser drilling system prevent mud invasion to formation and mitigates collapse of borehole wall. They reduce the risk of tool stack and improve data quality. Large diameter of riser pipe enhances variation of tool seizes. A couple of new tools were used for new measurement and improvement of the data quality. For example, SonicScanner (trademark of Schulumberger) successfully measured compressional and share velocity in very low velocities at the soft sediment, where it has been difficult to measure them with conventional DSI tool (Exp319). The stress and pore pressure in the borehole were measured with the wireline logging tool, (Schlumberger MDT). The single probe tool enable to measure temporal formation fluid pressure. The double packer tool enable to fracture test by sealing and pumping in the

  11. Logging cuts the functional importance of invertebrates in tropical rainforest.

    Science.gov (United States)

    Ewers, Robert M; Boyle, Michael J W; Gleave, Rosalind A; Plowman, Nichola S; Benedick, Suzan; Bernard, Henry; Bishop, Tom R; Bakhtiar, Effendi Y; Chey, Vun Khen; Chung, Arthur Y C; Davies, Richard G; Edwards, David P; Eggleton, Paul; Fayle, Tom M; Hardwick, Stephen R; Homathevi, Rahman; Kitching, Roger L; Khoo, Min Sheng; Luke, Sarah H; March, Joshua J; Nilus, Reuben; Pfeifer, Marion; Rao, Sri V; Sharp, Adam C; Snaddon, Jake L; Stork, Nigel E; Struebig, Matthew J; Wearn, Oliver R; Yusah, Kalsum M; Turner, Edgar C

    2015-04-13

    Invertebrates are dominant species in primary tropical rainforests, where their abundance and diversity contributes to the functioning and resilience of these globally important ecosystems. However, more than one-third of tropical forests have been logged, with dramatic impacts on rainforest biodiversity that may disrupt key ecosystem processes. We find that the contribution of invertebrates to three ecosystem processes operating at three trophic levels (litter decomposition, seed predation and removal, and invertebrate predation) is reduced by up to one-half following logging. These changes are associated with decreased abundance of key functional groups of termites, ants, beetles and earthworms, and an increase in the abundance of small mammals, amphibians and insectivorous birds in logged relative to primary forest. Our results suggest that ecosystem processes themselves have considerable resilience to logging, but the consistent decline of invertebrate functional importance is indicative of a human-induced shift in how these ecological processes operate in tropical rainforests.

  12. Logging cuts the functional importance of invertebrates in tropical rainforest

    Science.gov (United States)

    Ewers, Robert M.; Boyle, Michael J. W.; Gleave, Rosalind A.; Plowman, Nichola S.; Benedick, Suzan; Bernard, Henry; Bishop, Tom R.; Bakhtiar, Effendi Y.; Chey, Vun Khen; Chung, Arthur Y. C.; Davies, Richard G.; Edwards, David P.; Eggleton, Paul; Fayle, Tom M.; Hardwick, Stephen R.; Homathevi, Rahman; Kitching, Roger L.; Khoo, Min Sheng; Luke, Sarah H.; March, Joshua J.; Nilus, Reuben; Pfeifer, Marion; Rao, Sri V.; Sharp, Adam C.; Snaddon, Jake L.; Stork, Nigel E.; Struebig, Matthew J.; Wearn, Oliver R.; Yusah, Kalsum M.; Turner, Edgar C.

    2015-01-01

    Invertebrates are dominant species in primary tropical rainforests, where their abundance and diversity contributes to the functioning and resilience of these globally important ecosystems. However, more than one-third of tropical forests have been logged, with dramatic impacts on rainforest biodiversity that may disrupt key ecosystem processes. We find that the contribution of invertebrates to three ecosystem processes operating at three trophic levels (litter decomposition, seed predation and removal, and invertebrate predation) is reduced by up to one-half following logging. These changes are associated with decreased abundance of key functional groups of termites, ants, beetles and earthworms, and an increase in the abundance of small mammals, amphibians and insectivorous birds in logged relative to primary forest. Our results suggest that ecosystem processes themselves have considerable resilience to logging, but the consistent decline of invertebrate functional importance is indicative of a human-induced shift in how these ecological processes operate in tropical rainforests. PMID:25865801

  13. Log-Normal Turbulence Dissipation in Global Ocean Models

    Science.gov (United States)

    Pearson, Brodie; Fox-Kemper, Baylor

    2018-03-01

    Data from turbulent numerical simulations of the global ocean demonstrate that the dissipation of kinetic energy obeys a nearly log-normal distribution even at large horizontal scales O (10 km ) . As the horizontal scales of resolved turbulence are larger than the ocean is deep, the Kolmogorov-Yaglom theory for intermittency in 3D homogeneous, isotropic turbulence cannot apply; instead, the down-scale potential enstrophy cascade of quasigeostrophic turbulence should. Yet, energy dissipation obeys approximate log-normality—robustly across depths, seasons, regions, and subgrid schemes. The distribution parameters, skewness and kurtosis, show small systematic departures from log-normality with depth and subgrid friction schemes. Log-normality suggests that a few high-dissipation locations dominate the integrated energy and enstrophy budgets, which should be taken into account when making inferences from simplified models and inferring global energy budgets from sparse observations.

  14. Irrationality measures of $\\log 2$ and $\\pi/\\sqrt{3}$

    OpenAIRE

    Brisebarre, Nicolas

    2001-01-01

    Using a class of polynomials that generalizes Legendre polynomials, we unify previous works of E. A. Rukhadze, A. K. Dubitskas, M. Hata, D. V. and G. V. Chudnovsky about irrationality measures of $\\log 2$ and $\\pi/\\sqrt{3}$

  15. Logging technique for assaying for uranium in rocks

    International Nuclear Information System (INIS)

    Givens, W.W.

    1973-01-01

    A uranium exploration technique is described for determining the uranium content of a formation traversed by borehole. A delayed fission neutron assay log is obtained by irradiating the formation with repetitive bursts of fast neutrons and detecting delayed neutrons resulting from neutron fission of uranium at time intervals between the fast neutron bursts and after dissipation of the neutrons originating in the bursts. In addition, a response log is obtained by irradiating the formation with a source of fast neutrons whereby the neutrons from this source are moderated in the formation to lower energy levels and are subject to absorption. Secondary radiation attendant to these lower energy neutrons is recorded in order to obtain a log representative of the response of the formation to moderation and absorption of the neutrons. The two logs thus obtained are correlated in order to determine a corrected value of uranium content of the formation. (author)

  16. Cross-system log file analysis for hypothesis testing

    NARCIS (Netherlands)

    Glahn, Christian

    2008-01-01

    Glahn, C. (2008). Cross-system log file analysis for hypothesis testing. Presented at Empowering Learners for Lifelong Competence Development: pedagogical, organisational and technological issues. 4th TENCompetence Open Workshop. April, 10, 2008, Madrid, Spain.

  17. Modelling discontinuous well log signal to identify lithological ...

    Indian Academy of Sciences (India)

    1Indian School of Mines (ISM), Dhanbad 826 004, India. ... new wavelet transform-based algorithm to model the abrupt discontinuous changes from well log data by taking care of ...... the 11th ACM International Conference on Multimedia,.

  18. Assessment of procurement systems for unutilized logging residues ...

    African Journals Online (AJOL)

    ... in the forest after clear-cutting operation with cutto- length harvesting method. ... as system-2 can be preferable for the initial supply chain configuration in Turkey. ... Key words: logging residue, forest biomass, chipping, supply cost, biomass ...

  19. Midwest Logging Firm Perspectives: Harvesting on Increasingly Parcelized Forestlands

    Directory of Open Access Journals (Sweden)

    Shorna Allred

    2011-01-01

    Full Text Available Loggers play a critical role in the sustainable production of wood and paper products, and harvesting activities contribute to economic health and viability of many Upper Midwest communities in the United States. If the logging sector is unable to procure wood efficiently and economically from an increasingly parcelized land base, the competitive ability of the forest industry could be jeopardized. Little is known about the functions of the logging sector related to the forest resource land base on which they depend, and it is imperative to improve our understanding of this important part of the forest industry. The purpose of this study was to determine prospective attitudes about the future of the logging industry and how trends in forestland parcelization and harvesting mechanization are impacting the logging industry, especially as it relates to smaller tracts of land.

  20. Log-concave Probability Distributions: Theory and Statistical Testing

    DEFF Research Database (Denmark)

    An, Mark Yuing

    1996-01-01

    This paper studies the broad class of log-concave probability distributions that arise in economics of uncertainty and information. For univariate, continuous, and log-concave random variables we prove useful properties without imposing the differentiability of density functions. Discrete...... and multivariate distributions are also discussed. We propose simple non-parametric testing procedures for log-concavity. The test statistics are constructed to test one of the two implicati ons of log-concavity: increasing hazard rates and new-is-better-than-used (NBU) property. The test for increasing hazard...... rates are based on normalized spacing of the sample order statistics. The tests for NBU property fall into the category of Hoeffding's U-statistics...

  1. A Method for Visualizing Transaction Logs of a Faceted OPAC

    Directory of Open Access Journals (Sweden)

    Xi Niu

    2010-12-01

    Full Text Available The authors introduce a method for visualizing user transaction logs from a library catalog application. Simple visualization supporting intuitive or qualitative analysis to quickly make sense of complicated patterns can be a useful supplement or alternative to more common quantitative analysis. To this end, a visual flowchart is created illustrating an individual user session. This visualization can be used to qualitatively grasp user behavior within the application, possibly as an aid to identifying patterns or clusters of use. These flowcharts are created by automatically pre-processing apache transaction logs into an XML representation of meaningful user actions, which are then converted via JavaScript in a web browser to HTML table based flowcharts. The particular toolkit introduced is named Visualization for Understanding Transaction Logs (VUTL, and is available with an open source license. The toolkit has been prototyped with logs from the catalog applications of several academic and one public library.

  2. Ordinal Log-Linear Models for Contingency Tables

    Directory of Open Access Journals (Sweden)

    Brzezińska Justyna

    2016-12-01

    Full Text Available A log-linear analysis is a method providing a comprehensive scheme to describe the association for categorical variables in a contingency table. The log-linear model specifies how the expected counts depend on the levels of the categorical variables for these cells and provide detailed information on the associations. The aim of this paper is to present theoretical, as well as empirical, aspects of ordinal log-linear models used for contingency tables with ordinal variables. We introduce log-linear models for ordinal variables: linear-by-linear association, row effect model, column effect model and RC Goodman’s model. Algorithm, advantages and disadvantages will be discussed in the paper. An empirical analysis will be conducted with the use of R.

  3. Logging, arboricide treatments and regeneration at Budongo Forest

    African Journals Online (AJOL)

    activity was gradually replaced by the taungya system introduced in ... of this study were to: (i) assess the impact of past logging and arboricide .... effects on Budongo forest. ..... Large size individuals such as Croton, Cordia milenii and.

  4. Opportunities to reduce risk associated with nuclear logging techniques

    International Nuclear Information System (INIS)

    Wraight, P.D.; Robinson, E.; de Fleurieu, R.

    1991-01-01

    Nuclear logging provides petroleum exploration and production companies with data that are critical to their decisions and operations. Because this type data is so important, environmentally conscious well-logging and service companies are constantly reviewing the risks to people and environment associated with nuclear sources with the ALARA (as low as reasonably achievable) principle in mind. Opportunities to additionally reduce risks, which can be accomplished only with the active involvement of oil companies, are proposed in this paper

  5. Fluid-Rock Characterization and Interactions in NMR Well Logging

    Energy Technology Data Exchange (ETDEWEB)

    Hirasaki, George J.; Mohanty, Kishore K.

    2003-02-10

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

  6. Some properties of the log-Laplace distribution

    International Nuclear Information System (INIS)

    Uppuluri, V.R.R.

    1980-01-01

    A random variable Y is said to have the Laplace distribution or the double exponential distribution whenever its probability density function is given by lambda exp(-lambda abs. value y), where -infinity 0. The random variable X = exp(Y) is said to have the log-Laplace distribution. With the problem of extrapolation to low doses in dose response curves as motivation, an axiomatic characterization of the log-Laplace distribution is obtained. 1 figure

  7. Development of slimline logging systems for coal and mineral exploration

    International Nuclear Information System (INIS)

    Reeves, D.R.

    1976-01-01

    Recently, interest shown by multinational oil companies in mining prospecting has led to the requirement for more sophisticated slimline logging units, capable of given comparable results to conventional systems. Aspects of operating conditions and logging requirements are discussed, with particular reference to the effect on equipment design. Special consideration is given to the design and calibration of gamma ray, density, neutron, caliper and resistivity tools. Methods of handling data are discussed and the general application of these techniques to mineral work is considered

  8. MCEM algorithm for the log-Gaussian Cox process

    OpenAIRE

    Delmas, Celine; Dubois-Peyrard, Nathalie; Sabbadin, Regis

    2014-01-01

    Log-Gaussian Cox processes are an important class of models for aggregated point patterns. They have been largely used in spatial epidemiology (Diggle et al., 2005), in agronomy (Bourgeois et al., 2012), in forestry (Moller et al.), in ecology (sightings of wild animals) or in environmental sciences (radioactivity counts). A log-Gaussian Cox process is a Poisson process with a stochastic intensity depending on a Gaussian random eld. We consider the case where this Gaussian random eld is ...

  9. Data logging and online reconstruction in H1

    International Nuclear Information System (INIS)

    Fuhrmann, P.; Gerhards, R.; Kruener-Marquis, U.; Olsson, J.E.; Szkutnik, Z.

    1994-01-01

    In spring 1992, the H1 detector at the HERA electron proton collider at DESY came into operation. The high bunch crossing rate and, correspondingly, the large data volumes are placing demanding requirements on the data logging and event reconstruction. Both tasks are performed on an SGI Challenge series computer. This note reviews the development and the experience with the data logging and online reconstruction in H1

  10. Some properties of the log-Laplace distribution

    International Nuclear Information System (INIS)

    Uppuluri, V.R.R.

    1980-08-01

    A random variable γ is said to have the Laplace distribution or the double exponential distribution whenever its probability density function is given by lambda exp(-lambda absolute value (y)), where -infinity 0. The random variable X = exp(γ) is said to have the log-Laplace distribution. With the problem of extrapolation to low doses in dose response curves as a motivation, an axiomatic characterization of the log-Laplace distribution is obtained. 1 figure

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

    OpenAIRE

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

    2002-01-01

    A hypothesis that the financial log-periodicity, cascading self-similarity 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 lambda=2, which indicates that its real value should be close to this number. This applies even to a declining decelerating log-periodic phase. Crucial in this connection is identification o...

  12. Fluid-Rock Characterization and Interactions in NMR Well Logging

    Energy Technology Data Exchange (ETDEWEB)

    Hirasaki, George J.; Mohanty, Kishore K.

    2003-02-10

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

  13. Make Log Yield Analysis Part of Your Daily Routine

    Science.gov (United States)

    Jan Wiedenbeck; Jeff Palmer; Robert Mayer

    2006-01-01

    You haven't been conducting regular log yield studies because you don't have extra people to assign to the task. Besides, you've been around sawmills your whole life and have an innate sense of how your logs are yielding relative to the price you paid for them. Right? At the USDA Forest Service's hardwood marketing and utilization research lab in...

  14. Detection of attack-targeted scans from the Apache HTTP Server access logs

    Directory of Open Access Journals (Sweden)

    Merve Baş Seyyar

    2018-01-01

    Full Text Available A web application could be visited for different purposes. It is possible for a web site to be visited by a regular user as a normal (natural visit, to be viewed by crawlers, bots, spiders, etc. for indexing purposes, lastly to be exploratory scanned by malicious users prior to an attack. An attack targeted web scan can be viewed as a phase of a potential attack and can lead to more attack detection as compared to traditional detection methods. In this work, we propose a method to detect attack-oriented scans and to distinguish them from other types of visits. In this context, we use access log files of Apache (or ISS web servers and try to determine attack situations through examination of the past data. In addition to web scan detections, we insert a rule set to detect SQL Injection and XSS attacks. Our approach has been applied on sample data sets and results have been analyzed in terms of performance measures to compare our method and other commonly used detection techniques. Furthermore, various tests have been made on log samples from real systems. Lastly, several suggestions about further development have been also discussed.

  15. On the Ergodic Capacity of Dual-Branch Correlated Log-Normal Fading Channels with Applications

    KAUST Repository

    Al-Quwaiee, Hessa

    2015-05-01

    Closed-form expressions of the ergodic capacity of independent or correlated diversity branches over Log-Normal fading channels are not available in the literature. Thus, it is become of an interest to investigate the behavior of such metric at high signal-to-noise (SNR). In this work, we propose simple closed-form asymptotic expressions of the ergodic capacity of dual-branch correlated Log- Normal corresponding to selection combining, and switch-and-stay combining. Furthermore, we capitalize on these new results to find new asymptotic ergodic capacity of correlated dual- branch free-space optical communication system under the impact of pointing error with both heterodyne and intensity modulation/direct detection. © 2015 IEEE.

  16. Monte Carlo Study on Gas Pressure Response of He-3 Tube in Neutron Porosity Logging

    Directory of Open Access Journals (Sweden)

    TIAN Li-li;ZHANG Feng;WANG Xin-guang;LIU Jun-tao

    2016-10-01

    Full Text Available Thermal neutrons are detected by (n,p reaction of Helium-3 tube in the compensated neutron logging. The helium gas pressure in the counting area influences neutron detection efficiency greatly, and then it is an important parameter for neutron porosity measurement accuracy. The variation law of counting rates of a near detector and a far one with helium gas pressure under different formation condition was simulated by Monte Carlo method. The results showed that with the increasing of helium pressure the counting rate of these detectors increased firstly and then leveled off. In addition, the neutron counting rate ratio and porosity sensitivity increased slightly, the porosity measurement error decreased exponentially, which improved the measurement accuracy. These research results can provide technical support for selecting the type of Helium-3 detector in developing neutron porosity logging.

  17. Mitigating Hillslope Erosion After Post-fire Salvage Logging Operations

    Science.gov (United States)

    Robichaud, P. R.; Bone, E. D.; Brown, R. E.

    2017-12-01

    In the past decades, wildfires around the world have continued to increase in size, severity, and cost. Major concerns after wildfires are the increased runoff and erosion due to loss of the protective forest floor layer, loss of water storage, and creation of water repellent soil conditions. Salvage logging is often a post-fire forest management action to recoup the economic loss of the burned timber, yet concerns arise on the impacts of this activity on water quality. Recently, several studies have been conducted to determine the effect of salvage logging on hillslope erosion. Logging skid trails have been cited as being the cause of high erosion during and after salvage operations. We investigated the impacts of adding operational logging slash to skid trails to reduce hillslope erosion after salvage operations on the 2015 North Star Fire, Washington. We implemented well-designed rapid response approach to compare slash treatment effectiveness by monitoring sediment yield and runoff response from hillslopes with a concentrated flow (rill) experiment. Various runoff amounts are incrementally added to 4 m hillslope plots with and without slash treatments. Our initial results suggest that adding logging slash increased ground cover significantly which contributed to an order of magnitude decrease in hillslope erosion. Integrating erosion mitigation strategies into salvage logging operations should be commonplace when hillslope erosion is a concern.

  18. Generating porosity spectrum of carbonate reservoirs using ultrasonic imaging log

    Science.gov (United States)

    Zhang, Jie; Nie, Xin; Xiao, Suyun; Zhang, Chong; Zhang, Chaomo; Zhang, Zhansong

    2018-03-01

    Imaging logging tools can provide us the borehole wall image. The micro-resistivity imaging logging has been used to obtain borehole porosity spectrum. However, the resistivity imaging logging cannot cover the whole borehole wall. In this paper, we propose a method to calculate the porosity spectrum using ultrasonic imaging logging data. Based on the amplitude attenuation equation, we analyze the factors affecting the propagation of wave in drilling fluid and formation and based on the bulk-volume rock model, Wyllie equation and Raymer equation, we establish various conversion models between the reflection coefficient β and porosity ϕ. Then we use the ultrasonic imaging logging and conventional wireline logging data to calculate the near-borehole formation porosity distribution spectrum. The porosity spectrum result obtained from ultrasonic imaging data is compared with the one from the micro-resistivity imaging data, and they turn out to be similar, but with discrepancy, which is caused by the borehole coverage and data input difference. We separate the porosity types by performing threshold value segmentation and generate porosity-depth distribution curves by counting with equal depth spacing on the porosity image. The practice result is good and reveals the efficiency of our method.

  19. A comparison between elemental logs and core data

    International Nuclear Information System (INIS)

    Kerr, S.A.; Grau, J.A.; Schweitzer, J.S.

    1992-01-01

    Neutron-induced gamma-ray spectroscopy, of prompt capture and delayed activation, together with natural gamma-ray measurements, provides a borehole elemental analysis to characterize rock matrix composition. This study involved extensive core and log data in two wells. One well was drilled with a barite-weighted oil-based mud through a shallow marine sand. The other was drilled with fresh water-based mud through a channel sand, mudstone sequence overlying limestone. The results illustrate the importance of a suitable core sampling strategy and the problems associated with matching core to log data. Possible inaccuracies from the modelling of Ca-, Fe- and S-bearing minerals have been determined. A method for correcting the total measured aluminium concentration for that due to the borehole mud has been successfully tested against aluminium concentrations measured in the cleaned core samples. Estimates of the overall accuracy and precision of the elemental logging concentrations are obtained by comparing the log results with those obtained from the laboratory core analysis. A comprehensive core elemental analysis can also provide useful insight into the way other logs, such as the photoelectric factor or formation thermal neutron macroscopic absorption cross section, are influenced by minor and trace elements. Differences between calculated values from elemental logs and measured macroscopic parameters provide additional data for a more detailed understanding of the rock properties. (Author)

  20. Latent log-linear models for handwritten digit classification.

    Science.gov (United States)

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

    2012-06-01

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

  1. The human factors of implementing shift work in logging operations.

    Science.gov (United States)

    Mitchell, D L; Gallagher, T V; Thomas, R E

    2008-10-01

    A fairly recent development in the forest industry is the use of shift work in logging in the southeastern U.S. Logging company owners are implementing shift work as an opportunity to increase production and potentially reduce the cost of producing each unit of wood, without consideration of the potential impacts on the logging crew. There are many documented physiological and psychological impacts on workers from shift work in a variety of industries, although few address forestry workers in the U.S. Semi-structured interviews were performed to gather information about how logging company owners were implementing shift work in seven southeastern states. Data collected during the interviews included employee turnover, shift hours, shift scheduling, safety considerations, and production impacts. Various work schedules were employed. The majority of the schedules encompassed less than 24 hours per day. Permanent and rotating shift schedules were found. None of the logging company owners used more than two crews in a 24-hour period. Additional safety precautions were implemented as a result of working after dark. No in-woods worker accidents or injuries were reported by any of those interviewed. Results indicate that a variety of work schedules can be successfully implemented in the southeastern logging industry.

  2. PUMA Internet Task Logging Using the IDAC-1

    Directory of Open Access Journals (Sweden)

    K. N. Tarchanidis

    2014-08-01

    Full Text Available This project uses an IDAC-1 board to sample the joint angle position of the PUMA 76 1 robot and log the results on a computer. The robot is at the task location and the logging computer is located in a different one. The task the robot is performing is based on a Pseudo Stereo Vision System (PSVS. Internet is the transport media. The protocol used in this project is UDP/IP. The actual angle is taken straight from the PUMA controller. High-resolution potentiometers are connected on each robot joint and are buffered and sampled as potential difference on an A/D converter integrated on the IDAC-1. The logging computer through the Internet acting as client asks for the angle set, the IDAC-1 responds as server with the 10-bit resolution sampling of the joint position. The whole task is logged in a file on the logging computer. This application can give the ability to the Internet user to monitor and log the robot tasks anywhere in the Word Wide Web (www.

  3. Multiple Browsers Structure Tree Recruitment in Logged Temperate Forests.

    Directory of Open Access Journals (Sweden)

    Edward K Faison

    Full Text Available Historical extirpations have resulted in depauperate large herbivore assemblages in many northern forests. In eastern North America, most forests are inhabited by a single wild ungulate species, white-tailed deer (Odocoileus virginianus, and relationships between deer densities and impacts on forest regeneration are correspondingly well documented. Recent recolonizations by moose (Alces americanus in northeastern regions complicate established deer density thresholds and predictions of browsing impacts on forest dynamics because size and foraging differences between the two animals suggest a lack of functional redundancy. We asked to what extent low densities of deer + moose would structure forest communities differently from that of low densities of deer in recently logged patch cuts of Massachusetts, USA. In each site, a randomized block with three treatment levels of large herbivores-no-ungulates (full exclosure, deer (partial exclosure, and deer + moose (control was established. After 6-7 years, deer + moose reduced stem densities and basal area by 2-3-fold, Prunus pensylvanica and Quercus spp. recruitment by 3-6 fold, and species richness by 1.7 species (19%. In contrast, in the partial exclosures, deer had non-significant effects on stem density, basal area, and species composition, but significantly reduced species richness by 2.5 species on average (28%. Deer browsing in the partial exclosure was more selective than deer + moose browsing together, perhaps contributing to the decline in species richness in the former treatment and the lack of additional decline in the latter. Moose used the control plots at roughly the same frequency as deer (as determined by remote camera traps, suggesting that the much larger moose was the dominant browser species in terms of animal biomass in these cuts. A lack of functional redundancy with respect to foraging behavior between sympatric large herbivores may explain combined browsing effects that were

  4. Multiple browsers structure tree recruitment in logged temperate forests

    Science.gov (United States)

    Faison, Edward K.; DeStefano, Stephen; Foster, David R.; Rapp, Joshua M.; Compton, Justin A.

    2016-01-01

    Historical extirpations have resulted in depauperate large herbivore assemblages in many northern forests. In eastern North America, most forests are inhabited by a single wild ungulate species, white-tailed deer (Odocoileus virginianus), and relationships between deer densities and impacts on forest regeneration are correspondingly well documented. Recent recolonizations by moose (Alces americanus) in northeastern regions complicate established deer density thresholds and predictions of browsing impacts on forest dynamics because size and foraging differences between the two animals suggest a lack of functional redundancy. We asked to what extent low densities of deer + moose would structure forest communities differently from that of low densities of deer in recently logged patch cuts of Massachusetts, USA. In each site, a randomized block with three treatment levels of large herbivores–no-ungulates (full exclosure), deer (partial exclosure), and deer + moose (control) was established. After 6–7 years, deer + moose reduced stem densities and basal area by 2-3-fold, Prunus pensylvanica and Quercus spp. recruitment by 3–6 fold, and species richness by 1.7 species (19%). In contrast, in the partial exclosures, deer had non-significant effects on stem density, basal area, and species composition, but significantly reduced species richness by 2.5 species on average (28%). Deer browsing in the partial exclosure was more selective than deer + moose browsing together, perhaps contributing to the decline in species richness in the former treatment and the lack of additional decline in the latter. Moose used the control plots at roughly the same frequency as deer (as determined by remote camera traps), suggesting that the much larger moose was the dominant browser species in terms of animal biomass in these cuts. A lack of functional redundancy with respect to foraging behavior between sympatric large herbivores may explain combined browsing effects that were

  5. The frequency and level of sweep in mixed hardwood saw logs in the eastern United States

    Science.gov (United States)

    Peter Hamner; Marshall S. White; Philip A. Araman

    2007-01-01

    Hardwood sawmills traditionally saw logs in a manner that either orients sawlines parallel to the log central axis (straight sawing) or the log surface (allowing for taper). Sweep is characterized as uniform curvature along the entire length of a log. For logs with sweep, lumber yield losses from straight and taper sawing increase with increasing levels of sweep. Curve...

  6. Modeling and validating the grabbing forces of hydraulic log grapples used in forest operations

    Science.gov (United States)

    Jingxin Wang; Chris B. LeDoux; Lihai Wang

    2003-01-01

    The grabbing forces of log grapples were modeled and analyzed mathematically under operating conditions when grabbing logs from compact log piles and from bunch-like log piles. The grabbing forces are closely related to the structural parameters of the grapple, the weight of the grapple, and the weight of the log grabbed. An operational model grapple was designed and...

  7. 40 CFR 146.66 - Logging, sampling, and testing prior to new well operation.

    Science.gov (United States)

    2010-07-01

    ... cement bond and variable density log, and a temperature log after the casing is set and cemented. (ii..., gamma ray, and fracture finder logs before the casing is installed; and (B) A cement bond and variable density log, and a temperature log after the casing is set and cemented. (iii) The Director may allow the...

  8. Regeneration and management of lesser known timber species in the Peruvian Amazon following disturbance by logging

    DEFF Research Database (Denmark)

    Karsten, Rune Juelsborg; Meilby, Henrik; Larsen, Jørgen Bo

    2014-01-01

    Following the principles of Reduced Impact Logging (RIL) the construction of roads and log landings together with logging gaps are the most profound direct impacts that a forest operation has on the forest. While the effects of logging gaps have been studied in detail, the impacts of road and log...

  9. Fond ootab võistlusele laste omaloomingut

    Index Scriptorium Estoniae

    2005-01-01

    Avatud Eesti Fond kuulutab Euroopa kodanikuhariduse aasta puhul välja laste ja noorte omaloominguvõistluse, kuhu oodatakse teemal "Meie muudame maailma" lasteaia- ja algklassilaste joonistusi ja V-XII klassi õpilaste esseid

  10. Exercise Brings Bone Benefits that Last

    Science.gov (United States)

    ... Subscribe May 2014 Print this issue Health Capsule Exercise Brings Bone Benefits that Last En español Send ... lose bone. Studies of animals have shown that exercise during periods of rapid growth can lead to ...

  11. Localized cutaneous sporotrichosis lasting for 10 years

    Directory of Open Access Journals (Sweden)

    Rathi S

    2003-05-01

    Full Text Available A case of localized cutaneous sporotrichosis lasting for 10 years is being reported. The fixed cutaneous variety creates diagnostic difficulty by mimicking other conditions, chiefly lupus vulgaris.

  12. Last LEP superconducting module travels to surface

    CERN Multimedia

    Patrice Loïez

    2001-01-01

    The last superconducting module is raised from the Large Electron-Positron (LEP) collider tunnel, through the main shaft, to the surface. Superconducting modules were only used in the LEP-2 phase of the accelerator, from 1996 to 2000.

  13. Preparing last LEP superconducting module for removal

    CERN Multimedia

    Patrice Loïez

    2000-01-01

    The last superconducting module travels along the LEP tunnel towards one of the shafts where it will be lifted to the surface. Superconducting modules were only used in the LEP-2 phase of the accelerator, from 1996 to 2000.

  14. On the last digits of consecutive primes

    OpenAIRE

    Holt, Fred B.

    2016-01-01

    Recently Oliver and Soundararajan made conjectures based on computational enumerations about the frequency of occurrence of pairs of last digits for consecutive primes. By studying Eratosthenes sieve, we have identified discrete dynamic systems that exactly model the populations of gaps across stages of Eratosthenes sieve. Our models provide some insight into the observed biases in the occurrences of last digits in consecutive primes, and the models suggest that the biases will ultimately be ...

  15. Closed expressions for $\\int_{0}^{1} t^{-1} log^{n-1}t log^{p}(1 - t) dt$

    CERN Document Server

    Kölbig, Kurt Siegfried

    1982-01-01

    Closed expressions for the integral integral /sub 0//sup 1/ t/sup -1/ log/sup n-1/t log/sup p/(1-t)dt, whose general form is given elsewhere, are listed for n=1(1)9, p=1(1)9. A formula is derived which allows an easy evaluation of these expressions by formula manipulation on a computer. The majority of the above expressions are given in a microfiche supplement to the paper.

  16. Monte Carlo Numerical Models for Nuclear Logging Applications

    Directory of Open Access Journals (Sweden)

    Fusheng Li

    2012-06-01

    Full Text Available Nuclear logging is one of most important logging services provided by many oil service companies. The main parameters of interest are formation porosity, bulk density, and natural radiation. Other services are also provided from using complex nuclear logging tools, such as formation lithology/mineralogy, etc. Some parameters can be measured by using neutron logging tools and some can only be measured by using a gamma ray tool. To understand the response of nuclear logging tools, the neutron transport/diffusion theory and photon diffusion theory are needed. Unfortunately, for most cases there are no analytical answers if complex tool geometry is involved. For many years, Monte Carlo numerical models have been used by nuclear scientists in the well logging industry to address these challenges. The models have been widely employed in the optimization of nuclear logging tool design, and the development of interpretation methods for nuclear logs. They have also been used to predict the response of nuclear logging systems for forward simulation problems. In this case, the system parameters including geometry, materials and nuclear sources, etc., are pre-defined and the transportation and interactions of nuclear particles (such as neutrons, photons and/or electrons in the regions of interest are simulated according to detailed nuclear physics theory and their nuclear cross-section data (probability of interacting. Then the deposited energies of particles entering the detectors are recorded and tallied and the tool responses to such a scenario are generated. A general-purpose code named Monte Carlo N– Particle (MCNP has been the industry-standard for some time. In this paper, we briefly introduce the fundamental principles of Monte Carlo numerical modeling and review the physics of MCNP. Some of the latest developments of Monte Carlo Models are also reviewed. A variety of examples are presented to illustrate the uses of Monte Carlo numerical models

  17. The Effects of Different Forest Loggings on Forest Birds Community Composition in Shastkolateh Forest, Gorgan

    Directory of Open Access Journals (Sweden)

    F. Parsaei

    2014-06-01

    Full Text Available The species composition of a bird community is dependent upon many factors. Within any geographic area, vegetation structure may be the most important factor. The changes of bird community composition based on foraging behavior in relation to 3 different harvesting systems, including strip cutting, group selection logging, and single tree selection logging, was evaluated in a virgin area in this study. Birds and environmental variables were detected within 103 circle sampling plots with 25m radius. Based on the results, 4 groups of birds were observed in treatments based on the foraging behavior. Group 1 was ground foragers, group 2 consisted of foliage gleaning, group 3 included flycatchers, and group 4 represented bark foraging. The first group had the highest abundance in the strip treatment. The second group in group selection treatment, and the third and fourth groups had the highest abundance in the virgin area and then, in single tree selection treatment. The first group showed the highest correlation with shrub and herb or grass layer, stone cover and the number of trees 10-20m in height. The second, third and fourth groups showed the highest correlation with the number of trees>20m in height, basal areas, dead trees number, and the number of fagus trees. The results showed the single cutting treatment had a relatively minor effect on mature forest bird species and were more appropriate and sustainable methods to reduce the negative effects of forest harvesting on the birds.

  18. Local regularity analysis of strata heterogeneities from sonic logs

    Directory of Open Access Journals (Sweden)

    S. Gaci

    2010-09-01

    Full Text Available Borehole logs provide geological information about the rocks crossed by the wells. Several properties of rocks can be interpreted in terms of lithology, type and quantity of the fluid filling the pores and fractures.

    Here, the logs are assumed to be nonhomogeneous Brownian motions (nhBms which are generalized fractional Brownian motions (fBms indexed by depth-dependent Hurst parameters H(z. Three techniques, the local wavelet approach (LWA, the average-local wavelet approach (ALWA, and Peltier Algorithm (PA, are suggested to estimate the Hurst functions (or the regularity profiles from the logs.

    First, two synthetic sonic logs with different parameters, shaped by the successive random additions (SRA algorithm, are used to demonstrate the potential of the proposed methods. The obtained Hurst functions are close to the theoretical Hurst functions. Besides, the transitions between the modeled layers are marked by Hurst values discontinuities. It is also shown that PA leads to the best Hurst value estimations.

    Second, we investigate the multifractional property of sonic logs data recorded at two scientific deep boreholes: the pilot hole VB and the ultra deep main hole HB, drilled for the German Continental Deep Drilling Program (KTB. All the regularity profiles independently obtained for the logs provide a clear correlation with lithology, and from each regularity profile, we derive a similar segmentation in terms of lithological units. The lithological discontinuities (strata' bounds and faults contacts are located at the local extrema of the Hurst functions. Moreover, the regularity profiles are compared with the KTB estimated porosity logs, showing a significant relation between the local extrema of the Hurst functions and the fluid-filled fractures. The Hurst function may then constitute a tool to characterize underground heterogeneities.

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

    Science.gov (United States)

    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

    The ANDRILL (Antarctic Drilling Project) McMurdo Ice Shelf (MIS) project drilled 1285 m of sediment in Hole AND–1B, 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 AND–1B. 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 237–342 mbsf. In the upper part of AND–1B, clear alternations between low and high NGR values distinguish between diatomite (lacking minerals containing naturally radioactive K, U, and Th) and 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 AND–1B. On the basis of these three downhole logs, diamictite, claystones, and sandstones can be predicted correctly for 74% of the 692–1018 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.

  20. The application of radiation logs to groundwater hydrology

    Energy Technology Data Exchange (ETDEWEB)

    Scott Keys, W [United States Geological Survey, Denver, CO (United States)

    1967-05-15

    The drilling of exploratory holes to determine the availability of groundwater and to plan the most economical methods of water development is expensive. The only technique available at present for obtaining geological and hydrological information through the casing of pre-existing water wells and other boreholes is by radiation logging. Up to now these logging techniques have been little used in groundwater hydrology. This report describes inexpensive portable radiation logging equipment that is available or has been developed for groundwater studies in connection with a general research project on the application of borehole geophysics in groundwater hydrology. It is possible to obtain data on the following: the source, velocity, and chemical quality of groundwater; the location, extent, geometry, bulk density, porosity, permeability, and specific yield of aquifers and associated strata; and the position of casings, casing collars, leaks, perforations, and cement. The radiation logs employed include natural gamma, gamma-gamma, neutron-gamma. neutron epithermal-neutron. and radioactive tracer. The following radioisotopes are utilized: cobalt-60, plutonium-239, americium-241, and iodine-131. Typical radiation logs obtained by the various techniques are described and examples are given of practical applications of radiation logging to groundwater investigations. The applications cited are studies of perched water in basaltic rocks and associated sedimentary strata; the porosity, moisture content, and position of zones into which water was injected in volcanic tuff; the position of the interface between brine and fresh water in fine-grained carbonate rocks and associated fine clastic rocks; the interpretation of porosity from a neutron log; and the location by means of a radioactive tracer of the more permeable fracture zones in a well penetrating crystalline rock. (author)