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Building a Temporal GIS--Applied to Urban Landuse Zoning ChangeChiou, Jia-Cheng 06 September 2003 (has links)
Various activities and phenomenon in environment such as transportation, land resources exploitation and oceanic oil pollution can be analyzed and monitored by using GIS. But those will evolve when time elapses. In order to realize changes and implicit meaning in evolution, we can manage and analyze time-stamping geographic data (spatial-temporal data) in a temporal GIS. It is important to set up a spatial-temporal data model before building a temporal GIS. So, the focus of this research is the design of a relational spatial-temporal data model.
The major type of storing time of geographic data in the relational database of a GIS is to stamp each record with time (tuple-timestamping), so this method will be used in this research. The objective of this research is the development of a temporal GIS and makes the track of land use zoning change more convenient. The management and track of change of land use zoning data of Kaoshioung city is the case study in this research.
The ArcView 8.x software is used to develop a temporal GIS and spatial data and attribute data will be exported to geodatabase in it. Building spatial-temporal queries with ArcObject is the development of a temporal GIS in this research.
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Time-resolved optical beam induced current mapping of photonic deviceLiao, Yu-chi 01 July 2006 (has links)
Optical beam induced current mapping has found wide-spread applications in charactering semiconductor devices and integrated circuitry. Conventionally a focused cw laser beam is employed to excite carriers in the depletion region that is subsequently detected to form the contrast signal for scanning imaging. Device defects that may quench the photo-generated carriers can then be easily revealed. However, such detection is static in nature and the dynamics behavior of a device remains unknown. In this study, we are using a pulsed laser with high repetition rate and a high frequency phase sensitive lock-in loop to achieve temporal resolution at sub-nanosecond. In this way, the temporal response at a selected position on the device can be characterized
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Investigating the effect of impedance matching on LED with Time-resolved Electro-luminescence MicroscopyLin, Li-wei 23 July 2007 (has links)
As the great studies have been made in light emitting diodes, the application becomes more variety for different field. High bright light emitting diodes apply a new light source for fluorescence lifetime measurements. We use confocal scanning microscopy and a high frequency sensitive lock-in amplifier to obtain the electroluminescence image at ten of micrometer. We drive the light emitting diodes by radio frequency signal and observe it. We parallel connection an inductance to match the parasitic capacity in high frequency to obtain better light emitted brightness.
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The Research of Maintaining Consistency on Process Timing ConstraintsLin, Hsin-Nan 22 June 2000 (has links)
The advances of information technologies have forced many enterprises to reconsider the way their business processes are conducted. Among the various information technologies, workflow management systems (WFMSs) are widely recognized as an effective tool to greatly improve the efficiency of business processes and customers¡¦ satisfaction. Today, a great number of commercial WFMSs have been available on the market; however, none of them are very successful due to the lack of some important features. One of the features that are needed by many business processes is the specification and enforcement of time constraints. In this thesis, we propose a time constraint model that helps workflow designer to define and verify time constraints. Different constraints may be verified at different times, e.g., definition time, invocation time, execution time. A workflow instance, once detected as a violation of some time constraint, could be terminated immediately to avoid the waste of precious resources as well as to provide prompt response to users. A variety of algorithms for verifying time constraints are proposed and analyzed.
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Calibration of Time Domain Network Analyzer MeasurementsSu, Kuo-Ying 06 July 2000 (has links)
none
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Comparison Study of Space-Time Coded SystemsLin, Wei-Sen 05 August 2003 (has links)
The limit of bandwidth efficiency is well known in wireless radio communication. Therefore, making use of bandwidth efficiently is very important. Among various technologies which can increase the bandwidth efficiency, space-time coding system is very popular technology recently. In this article, we¡¦ll discuss three common schemes in ST system¡GSpace-Time Trellis Coding (STTC), Space-Time Block Coding (STBC) and Differential Space-Time Block Coding (DSTBC). First, we¡¦ll introduce the basic model of ST systems in chapter 2. And in chapter 3, the error probability, which is a close form, of STBC and DSTBC systems in slow fading channel will be derived, according to the derivation of error probability in multi-channel communication systems¡i10¡j. Then, the channel model will be defined as a fast fading channel and the error probability of STBC system in this channel model will be derived in chapter 4. Furthermore, we¡¦ll derive the error probability of STBC system in multi-path slow fading channel. Finally, we¡¦ll make a conclusion to the works we did in this article.
The contribution of this article are¡G1. We derive a bit error probably which is a close form of STBC and DSTBC systems in slow fading channel. 2. We analyze the performace of STBC system in fast fading channel and derive a bit error probability in this case. 3. We analyze the performance of STBC system in multi-path slow fading channel and get a result that the diversity gain will increase when use the RAKE receiver mentioned in this article.
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Overland flow time of concentration on flat terrainsChibber, Paramjit 15 November 2004 (has links)
Time of concentration parameter is defined very loosely in literature and it is calculated rather subjectively in practice (Akan 1986). The situation becomes adverse as the terrain slope approaches zero; because the slope generally appears in the denominator of any formula for time of concentration, this time goes to infinity as the slope goes to zero. The variables affecting this time parameter on flat terrains have been studied through plot scale field experiments. It has been found that the antecedent moisture and rainfall rate control this parameter. Some of the existing time of concentration methods have been compared, and it is found that all the empirical models compared under predict this time parameter. This under prediction can be attributed first to the differing concepts of time of concentration previous researchers have modeled, secondly to the absence of any accounting for the initial moisture content in their respective equations and thirdly to the watersheds where these models have been calibrated. At lower time of concentrations, Izzard-based model predictions show some results close to the observed values. A methodology to determine the plot scale surface undulations has been developed to estimate the depression storage. Regression equations have been derived based upon the experiments to determine the overland flow times on a flat plot of 30 feet length with uniform rainfall intensity. The application of these equations on other lengths cannot be ascertained. Equations for the hydrograph slope on flat terrains have been determined for bare clay and grass plots.
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Device for automating in vitro characterization of lymphatic vessel functionRajagopalan, Shruti 17 February 2005 (has links)
The lymphatic system consists of a network of vessels which work to return the
interstitial fluid back to the blood circulation. Individual units called lymphangions,
segments of lymphatic vessels between two valves, pump cyclically to propel lymph.
Lymphangions are similar to the heart in that they are sensitive to both preload and
afterload. To describe the heart independent of preload and afterload, investigators
developed the concept of time-varying elastance. We evaluated the applicability of this
concept to lymphangions by analyzing preliminary data obtained from the bovine
mesenteric vessels. We found that there were some limitations to the applicability of this
concept to lymphangions, as there was a high degree of variability with respect to
contraction strength and frequency of individual time-varying elastance curves. To better
characterize lymphangion mechanics, we built a device which would enable real-time
isobaric, isometric and isotonic experiments in vitro. We performed all three experiments
on lymphatic vessel segments and obtained input and output pressures, output flow,
instantaneous radii and wall tension. The characterization of the lymphangion using these
parameters can be the first step to simulate the behavior of a lymphatic vesssel and later
the behavior of an entire lymphatic system.
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A web-based timesheet tool for the design studioKim, Young-No 01 November 2005 (has links)
This research is related to time management and the use of timesheets in
architectural design education. It focuses on the role of Web-based timesheets in the
architectural design studio. The main purpose of the research is to explore whether
Web technology is helpful in increasing compliance with time documentation and can
determine which student behaviors and habits can be observed with Web-based
timesheets in architectural design education.
In time management, using timesheets is a common method to analyze time
usage. However, a traditional timesheet is usually focused on the investigator's (teacher
or employer) perspective. Therefore active participation is hardly expected and data
analysis is not easily offered to participants as useful information in real time. To
overcome the identified problems, Web technology may be useful.
For this research, a pilot software tool was developed and tested in design
studios at several grade levels. Research was focused on empirical observation to
determine which student work patterns and behaviors can be observed with a Webbased
timesheet tool.
The Web-based timesheet tool was successfully fielded in the design studio and the utility of the Web-based timesheet tool was observed. By analyzing the collected
data from the experiments with this Web-based timesheet tool, it was possible to
observe various work patterns and behaviors and to develop insights in the students'
design process. Analysis of log data gave interesting insights into students' work
patterns and design behaviors. Web technology was helpful in increasing the value of
the timesheet in architectural design education.
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Parental time and children's obesity measures: a theoretical and empirical investigationYou, Wen 25 April 2007 (has links)
The increased prevalence of childhood obesity is a major concern for society. This
study aims at exploring the influence of the parents (especially parental time allocation
choices) on childrenâÂÂs obesity-related health outcomes and examining the potential
differences between the fathersâ and the mothersâ marginal effects.
A household with two parents and one child is modeled. The household production
theory and the collective household modeling structure are combined. The model treats
the mother, the father and the child as three separate agents with individual preferences.
The two parentsâ interaction is modeled within the collective model framework by
assuming that they will reach Pareto efficient resource allocation between them. In order
to capture the dynamics between parents and the child, parents-child interaction is
modeled in a two-stage Stackleberg game structure where the child is allowed to have
certain decision choices of his/her own. This game structure allows us to explore the
parental influence on the childâÂÂs health outcomes while allowing the child to have
influencing power in the household decision-making process. Based on this theoretical model, a general triangular system with one childâÂÂs health
production equation and five health inputs demand equations is derived and estimated.
The empirical estimation is performed for three systems: pooled model, the younger
children model (of age 9 to 11), and the older children model (of age 13 to 15).
The empirical results show mother-related variables show more influence on the
childâÂÂs Body Mass Index (BMI) outcomes compared to father-related variables:
mothersâ BMI and mothersâ work-to-home stress spillover are positively related to their
childrenâÂÂs BMI while mothersâ time spent with their children is negatively related to
their childrenâÂÂs BMI. There exists a complementary relationship between mothersâÂÂ
income and fathersâ food preparation time. In the older children model, mothersâ own
income increases tend to decrease their time spent with their children.
The main contribution of this study is that it develops a general theoretical
framework to capture the dynamics in parents-child interaction. Based on this theoretical
model, empirical analysis and future work can be conducted in a theoretically consistent
way.
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