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81.
This paper presents the design and implementation of an integrated application program called ArcFVS that links the Forest Vegetation Simulator (FVS) and a Geographic Information System (GIS) to realize spatial selection of input files and graphic display of modeling output. Data for testing and running the model came from the U.S. Forest Service’s Forest Inventory and Analysis (FIA) Database and were also collected in field surveys in north-central Indiana. ArcFVS 1.0 is designed using the ArcGIS software from the Environmental Systems Research Institute (ESRI) and the Visual Basic for Applications (VBA) programming environment to manipulate ESRI’s ArcObjects. The resulting product offers custom functions as commands in a new menu or as tools on a new toolbar. They are used to: select spatially or by attribute the forest plots to be projected by FVS, create the FVS input files for the selected plots and display in a geospatial environment different types of FVS output (text output files, tables with variables of interest and visualization image files). Advantages of ArcFVS 1.0 include the new GIS capabilities, enhanced format translation functions and the standardized programming environment. 相似文献
82.
Jongchul Song Walter R. Fagerlund Carl T. Haas Clyde B. Tatum Jorge A. Vanegas 《Canadian Metallurgical Quarterly》2005,131(6):723-733
Prefabrication, preassembly, modularization, and off-site fabrication, collectively termed as prework have become more viable with recent advances in design and information technologies. These construction methods offer a substantial opportunity to improve project performance when circumstances merit. Successful implementation of these methods on a particular project requires systematic analysis and early decision making based on specific factors of the project. This paper identifies those factors influencing decisions on the use of prework, and current industry practices for evaluating the applicability of prework on industrial projects. It then presents a decision framework to assist industry practitioners with evaluating the applicability of prework on their project, and describes a computerized tool to aid project teams in the decision-making process. The developed framework and tool are useful and effective in the decision-making process, and easy to use, as validated by practitioners in the industry. 相似文献
83.
Ferrer Emilio; Salthouse Timothy A.; McArdle John J.; Stewart Walter F.; Schwartz Brian S. 《Canadian Metallurgical Quarterly》2005,20(3):412
Longitudinal multivariate mixed models were used to examine the correlates of change between memory and processing speed and the contribution of age and retest to such change correlates. Various age- and occasion-mixed models were fitted to 2 longitudinal data sets of adult individuals (N > 1,200). For both data sets, the results indicated that the correlation between the age slopes of memory and processing speed decreased when retest effects were included in the model. If retest effects existed in the data but were not modeled, the correlation between the age slopes was positively biased. The authors suggest that although the changes in memory and processing speed may be correlated over time, age alone does not capture such a covariation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
Finding changed identifiers is important for understanding the difference between two versions of a program and for detecting and resolving conflicts while merging variants of a program together. Standard practice for differencing and merging relies on line based techniques that do not recognize renamed identifiers. The design and implementation of a tool to automatically detect renamed identifiers between two versions of a program is presented. The system uses an abstract representation of language constructs to enable language awareness without introducing language dependence. Modules for Java and Scheme have been written. The detector works with multiple file pairs, taking into account renamings that span several files. A case study is presented that demonstrates proof of concept. The detector is part of a suite of intelligent differencing and merging programs that exploit the static semantics of programming languages. 相似文献
85.
86.
Reuter M.; Stark R.; Hennig J.; Walter B.; Kirsch P.; Schienle A.; Vaitl D. 《Canadian Metallurgical Quarterly》2004,118(3):462
Although it is known that there are fundamental personality differences in the behavioral responses to emotional stimuli, traits have scarcely been investigated in this context by means of functional imaging studies. To maximize the variance with respect to personality, the authors tested 12 control subjects and 12 subjects who had sadomasochistic experiences with respect to the relationship between J. A. Gray's (1970) personality dimensions, the behavioral approach system (BAS) and the behavioral inhibition system (BIS), and brain activity in regions of interest. The BIS was associated with activity in numerous brain areas in response to fear, disgust, and erotic visual stimuli, whereas few associations could he detected between the BAS and brain activity in response to disgust and erotic stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
Kalman David; Kahler Christopher W.; Tirch Dennis; Kaschub Cynthia; Penk Walter; Monti Peter M. 《Canadian Metallurgical Quarterly》2004,18(1):78
This study reports findings from an investigation of the efficacy of high-dose nicotine patch (NP) therapy for heavy smokers with a past history of alcohol dependence. One hundred thirty participants were randomly assigned to 42 mg or 21 mg of transdermal nicotine for 4 weeks, followed by an 8-week dose titration. Follow-up assessments were conducted at 4 and 12 weeks. Differences between dose conditions were nonsignificant, although unexpectedly, outcomes favored participants in the 21-mg NP condition. Nicotine abstinence at follow-up was related to longer length of alcohol abstinence at time of enrollment. Future research should investigate ways to improve smoking quit rates in this population, including more frequent counseling sessions and/or other pharmacotherapies. These investigations should focus primarily on smokers in early alcohol recovery. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
To maintain the original distribution pattern of diffusible elements in biological samples, electron probe microanalysis is carried out with frozen hydrated bulk specimens and cryosections, analysed at temperatures below 130 K. Ice has a very low intrinsic conductivity at this working temperature and surface- and space-charging appears, when uncoated specimens are irradiated with non-penetrating electrons. Although coating with a grounded conductor abolishes the surface potential, the build-up of an internal space-charge field is possible, depending on the sample thickness and beam voltage used. Consequently, the geometry of the X-ray source volume and the spectral distribution of the emitted continuous and characteristic X-rays are affected. To simulate the situation for microanalysis of frozen hydrated specimens the charging process in electron irradiated ice is studied by recording simultaneous specimen currents from the top and bottom of ice layer preparations. The external currents yield information on the build-up of internal space-charge fields which result from the balance of charge injection, storage, and transport. Irradiation of uncoated bulk specimens with a finely focused beam results in the build-up of a space-charge field close to the surface, which causes a reduction of the depth of microprobe analysis. In coated bulk specimens the induced conductivity renders possible a current flow to the front electrode, thereby limiting the space-charge field. Sections with an effective rear electrode will not charge appreciably if the electron range is larger than about half the section thickness. 相似文献
89.
Walter Michaeli Dirk Opfermann Thomas Kamps 《The International Journal of Advanced Manufacturing Technology》2007,33(1-2):206-211
In micro systems technology, the process of micro assembly injection moulding is used for the generation of hybrid micro systems.
With this process, more functions are integrated in less space. In the field of medical technology, miniaturisation also means
new methods of treatment with fewer side effects on the patient. New cures are developed by the miniaturisation of medical
instruments, such as keyhole surgery. For detailed investigations a specific demonstration was developed to display the potential
of micro assembly injection moulding in medical science. This part consists of a carbon-fibre reinforced PEEK puncture needle,
which incorporates three lumens. The selected materials allow use of the needle during magnetic resonance imaging. In order
to attach additional equipment a plastic connector needs to be overmoulded on the needle. The investigations focus on the
injection moulding process by characterising the influences of temperature, moulding parameters and material combinations
on the resulting bond strength between needle and connector. 相似文献
90.