In a large scale environment humans rely on their mental representations cognitive maps to solve navigational problems. To approach the understanding of how humans acquire, process, and utilize information from the environment, three groups of participants in this study performed several experiments associated with finding their way in a previously unknown environment. Experimental tasks included route retracing, pointing to previously visited locations, and a questionnaire regarding wayfinding strategies and cognitive map development. Each of three groups of participants was in one of three unique conditions: 1. learning and retracing with navigational landmarks indicating right and left turns at decision points; 2. during route retracing only generic landmarks were present at decision points (landmarks indicating left and right were present during learning but replaced during retracing); and 3. no landmarks were present during route retracing (landmarks indicating left and right were present during learning but removed before retracing started). Results supported the hypothesis that during the initial stages of visiting an unknown environment we build metric knowledge together with non-metric knowledge associated with the broad categories of landmark and route knowledge. In addition, the environment plays an important role in wayfinding performance and that characteristics of the environment contribute differently to the development of our cognitive map. Last but not least, the strategies humans use to solve wayfinding problems in a novel environment are not based on an individual type of environmental knowledge; in fact, we switch between different types of environmental knowledge when necessary. Shifting between strategies appears to be from more familiar environmental knowledge to less familiar knowledge. In particular, participants from group 3 (no landmarks during the retracing period) were more likely to walk off-route during retracing but exhibited more accurate metric knowledge of the environment. Based on the results of this experiment, they combined route- and survey-based strategies in wayfinding and switched from the most familiar knowledge to a less familiar strategy.

The increasing interest and focus on unconventional reservoirs is a result of the industry's direction toward exploring alternative energy sources. It is due to the fact that conventional reservoirs are being depleted at a fast pace. Shale gas reservoirs are a very favorable type of energy sources due to their low cost and long-lasting gas supply. In general, according to Ausubel (1996), natural gas serves as a transition stage to move from the current oil-based energy sources to future more stable and environment-friendly ones. By looking through production history in the U.S Historical Production Database, HPDI (2009), we learn that the Barnett Shale reservoir in Newark East Field has been producing since the early 90's and contributing a fraction of the U.S daily gas production. Zhao et al. (2007) estimated the Barnett Shale to be producing 1.97 Bcf/day of gas in 2007. It is considered the most productive unconventional gas shale reservoir in Texas. By 2004 and in terms of annual gas production volume, Pollastro (2007) considered the Barnett Shale as the second largest unconventional gas reservoir in the United States. Many studies have been conducted to understand better the production controls in Barnett Shale. However, this giant shale gas reservoir is still ambiguous. Some parts of this puzzle are still missing. It is not fully clear what makes the Barnett well produce high or low amounts of gas. Barnett operating companies are still trying to answer these questions. This study adds to the Barnett chain of studies. It tests the effects of the following on Barnett gas production in the core area (Denton, Wise, and Tarrant counties): * Barnett gross thickness, including the Forestburg formation that divides Barnett Shale. * Perforation footage. * Perforated zones of Barnett Shale. Instead of testing these parameters on each well production decline curve individually, this study uses a new technique to simplify this process. Decline Map Analysis (DMA) is introduced to measure the effects of these parameters on all production decline curves at the same time. Through this study, Barnett gross thickness and perforation footage are found not to have any definite effects on Barnett gas production. However, zone 3 (Top of Lower Barnett) and zone 1 (Bottom of Lower Barnett) are found to contribute to cumulative production. Zone 2 (Middle of Lower Barnett) and zone 4 (Upper Barnett), on the other hand, did not show any correlation or influence on production through their thicknesses.

Using rice chromosome 1 pseudomolecule as a reference, a minimal tiling path for the euchromatic arms of sorghum chromosome 3 was constructed, in which 23 contigs contain an estimated 57.56 Mb of DNA. A total of 409 EST-STS markers and 255 genetic markers have been mapped onto the euchromatic arms providing excellent integration of the genetic and physical maps. A total of 21 contigs containing 9 ESTSTS and 35 genetic markers have been constructed across the heterochromatin block of sorghum chromosome 3 which comprise 16.57 Mb of DNA. Macrocolinearity between sorghum chromosome 3 and rice chromosome 1 was examined based on the mapped EST-STS markers. Approximately 85% of the EST-STS markers were colinear between these two homeologous chromosomes. Estimates of recombination were also determined, which indicates the existence of recombination cold and hot spots. Microcolinearity between sorghum chromosome 3 and rice chromosome 1 was examined at two different levels. In one case, overlapping sorghum BAC pools orthologous to a 5.1 Mb region of rice chromosome 1 were constructed and sequence skimmed. Alignment of the sorghum skim sequences to the TIGR rice gene models revealed ~62% colinearity between the two orthologous regions. In addition, colinearity between sorghum chromosome 3 and rice chromosome 5 was detected within this region which is likely due to the segmental homology between rice chromosome 1 and rice chromosome 5. Microcolinearity between sorghum and rice was also examined by comparing 2 fully sequenced sorghum chromosome 3 BAC clones to the orthologous region of rice chromosome 1. In this analysis, ~65% colinearity was detected for sorghum BAC 82G24 and ~59% colinearity was detected for sorghum BAC 181g10. Microcolinearity was largely confined to gene coding regions and sequences of exons displayed the highest percent identities. Small-scale gene rearrangements were also detected. Finally, RT-PCR analysis was carried out between a set of colinear and non-colinear genes from sorghum and rice to determine whether the loss of colinearity between orthologous genes resulted in a change in transcriptional regulation. No direct link between loss of colinearity and expression pattern was detected in these experiments.

The F-box protein Skp2 (S-phase kinase associated protein 2) positively regulates the G1-S transition by controlling the cell cycle inhibitor p27Kip1. The p42/p44 mitogen-activated protein (MAP) kinase activation is also necessary for the cell cycle progression. p27Kip1 acts as a negative regulator of the cell cycle by inhibiting the activity of cyclin/cdk complexes during G0 and G1. RT-PCR, Western blotting and immunohistochemical staining were used to assay their relationship with cervical lesion development. In RT-PCR and western blotting, Skp2 mRNA and protein were expressed mostly in carcinoma tissues. At Fisher¡¦s exact test showed that Skp2, p27Kip1 and p42/p44 MAP Kinase are strongly associated with disease progession respectively (P < 0.0001, P < 0.0001, P = 0.0043). We also found a postive correlation between the expression of Skp2 and p42/p44 MAP Kinase (P = 0.0097).

¡@¡@e-Learning is becoming more and more important for many educational institutions, and many educators believe that there is a good potential for providing adaptive learning in e-learning environment. In order to support the design of adaptive learning materials, teachers need to refer to the ontology of the subject domain to be taught. Moreover, ontology can show the whole picture and the core knowledge of a subject domain. Literature reviews also pointed out that graphical representation of ontology can reduce the problems of information overloading and learning disorientation for learners. However, ontology constructions all rely on domain experts in the past; it is a time consuming and high cost task. It would be more challenge for those emerging new domains like e-Learning. ¡@¡@e-Learning is a new and fast developing domain, how to automatic constructing its ontology is a very important topic. In this research, we use some relevant e-Learning journals and conferences papers as input data sources, and apply data mining techniques to automatically construct the concept maps for e-learning. We also analyzed the evolution in e-Learning domain according to the concept maps constructed at different time periods. ¡@¡@The contribution of this research is automatic constructing the concept maps of e-Learning domain using text-mining techniques. It can provide a comprehensive and useful reference for researchers to do research, for teachers to do adaptive course design and for learners to understand the related knowledge in e-Learning.

The main idea of strategy map is to compensate for the exceedingly static balance scorecard and to have the four frameworks more logically arranged. Strategic action is a dynamic system existing in the four frameworks of balance scorecard. Policymakers tend to pay too much attention to the variations of the short-time measurements than the long-term structural effect of system. Through time delay and the effect of negative feedback loops, strategic actions may cause the change of loops, leading to some side effects or counterintuition. As a result, managers may fail to correctly analyze situations and make appropriate decisions, have a complete strategic planning, and have the strategic goal expectably achieved. Public Television Service is a nonprofit corporation with properties of wireless television corporation and nonprofit organization simultaneously. Based on article 2 of the law of PTS, governmental donations of foundations for which a budget is prepared in accordance with this Law shall be reduced by ten percent each year until the third fiscal year; according to article 41, the station may not broadcast business commercials¡K This clause brings about an innate problem that it prevents PTS from raising money by dealing with commercial pursuits. With governmental donations barely increased, improving funds-raising ability has become an important object of PTS. With limited financial resource, PTS requires a dynamic managerial tool to keep its balance between the object of public welfare and the budget. The purpose of this article is to discuss the dynamic relations among strategic themes, actions and measurements on the strategy map of PTS, and to map the management system by qualitative and quantitative system dynamics. According to the result of secondary data analysis and the interviews, this research constitutes the strategy map of PTS based on strategic themes of four frameworks, modeling each sub-system. After testing, basic simulating and policy simulating, we can then explore the interaction among all sub-systems. Based on the theory of improving the dynamic alignment of balance scorecard strategy in system dynamics, this research models the system of PTS by intuitional and systematically-thinking methods separately. The results shows: 1. In the systems constructed by BSC and strategy map, dynamic relations exist in each component. Strategies may turn out to be counter-intuitional owing to time delay, and the effects of positive and negative loops. 2. Policy laboratory made by system dynamics can be used to simulate the policies. Leading and lag index of BSC also have dynamic properties. Therefore, when setting strategy goals or KPI, managers have to consider the influence caused by loops and time delay. In addition, the outcome of policy and case simulation reveals: 1. If the quality of TV programs does not progress in company with its service, the system will fall into the crisis of growth limit. 2. Improving service quality one-sidedly may lead to an effect disappointing or being detected after a long time because of time delay. 3. When executing the strategy to improve the quality of TV programs (to increase the budget of TV programs), PTS should manage to raise service capacity and satisfaction to reduce the force of negative feedback loops and maintain the policy effect.

In this thesis, we propose a knowledge map integration system to merge distributed knowledge maps into a global knowledge map based on the concept mapping methodology. This system performs the functions of knowledge map integration and knowledge map maintenance. The knowledge map integration function integrates different local knowledge maps specified by distributed organizations into a global knowledge map, and knowledge seekers can access the overall knowledge structure about the domain knowledge. Besides, the local knowledge maps in different organizations vary dynamically due to accumulation of information. Consequently, the demand for knowledge map maintenance increases in order to keep the global knowledge map up to date. The function of knowledge map maintenance can update the variations of every local knowledge map, and change the global structure simultaneously. The knowledge map integration system is evaluated by master thesis repository at National Central Library, and we obtain good results.

High-resolution physically ordered gene maps for the horse (Equus caballus, ECA) are essential to the identification of genes associated with hereditary diseases and traits of interest like fertility, coat color, and disease resistance or susceptibility. Such maps also serve as foundations for genome comparisons across species and form the basis to study chromosome evolution. In this study seven equine chromosomes (ECA6, 7, 10, 15, 18, 21 and X) corresponding to human chromosomes (HSA) 2, 19 and X were selected for high-resolution mapping on the basis of their potential involvement in diseases and conditions of importance to horses. To accomplish this, gene- and sequence-specific markers were generated and genotyped on the TAMU 5000rad horse x hamster RH panel. Additionally, screening of a BAC library by overgoes and subsequent STS content mapping and fingerprinting approaches were used to assemble and verify a BAC contig along a ~5 Mb span on ECA21. Dense gene maps were generated for each of the seven equine chromosomes by adding 408 new markers (285 type I and 123 type II) to the current maps of these chromosomes, thereby greatly improving overall map resolution to one mapped marker every 960kb on average (range: 700 kb – 1.3 Mb). Moreover, the contig on ECA21 contained 47 markers (42 genes and 5 microsatellites) as well as 106 STS markers distributed along 207 BAC clones. Comparisons of these maps with other species revealed a remarkably high level of horse-human X chromosome conservation, as well as two evolutionary breakpoints unique to Perissodactyls or Equids for the equine homologues of HSA19 and HSA2, one of which has been more precisely localized by the ECA21 contig. Thus, high resolution maps developed for these chromosomes i) provide a basis to map traits of interest rapidly to specific chromosomal regions, ii) facilitate searches for candidate genes for these traits by fine comparisons of the equine regions with corresponding segments in other species, and iii) enable understanding the evolution of the chromosomes. Expansion of this work to the entire equine genome will be important for developing novel strategies for diagnosis, prevention, and treatment of equine diseases.

Iterative decoding and codes on graphs were first devised by Gallager in 1960, and then rediscovered by Berrou, Glavieux and Thitimajshima in 1993. This technique plays an important role in modern communications, especially in coding theory and practice. In particular, low-density parity-check (LDPC) codes, introduced by Gallager in the 1960s, are the class of codes at the heart of iterative coding. Since these codes are quite general and exhibit good performance under message-passing decoding, they play an important role in communications research today. A thorough analysis of iterative decoding systems and the relationship between maximum a posteriori (MAP) and belief propagation (BP) decoding was initiated by Measson, Montanari, and Urbanke. This analysis is based on density evolution (DE), and extrinsic information transfer (EXIT) functions, introduced by ten Brink. Following their work, this thesis considers the MAP decoding thresholds of three iterative decoding systems. First, irregular repeat-accumulate (IRA) and accumulaterepeataccumulate (ARA) code ensembles are analyzed on the binary erasure channel (BEC). Next, the joint iterative decoding of LDPC codes is studied on the dicode erasure channel (DEC). The DEC is a two-state intersymbol-interference (ISI) channel with erasure noise, and it is the simplest example of an ISI channel with erasure noise. Then, we introduce a slight generalization of the EXIT area theorem and apply the MAP threshold bound for the joint decoder. Both the MAP and BP erasure thresholds are computed and compared with each other. The result quantities the loss due to iterative decoding Some open questions include the tightness of these bounds and the extensions to non-erasure channels.

Reproduction de : Thèse de doctorat : Pharmacie. Pharmacochimie : Nantes : 2007. / Bibliogr.