• 대기
• /
• 제25권3호
• /
• pp.483-499
• /
• 2015

This study examined the impact of change of land-use and meteorological condition due to urbanization on heat environment in Seoul metropolitan area over a decade (2000 and 2009) using Weather Research and Forecasting (WRF)-Urban Canopy Model (UCM). The numerical simulations consist of three sets: meteorological conditions of (1) October 2000 with land-use data in 2000 (base simulation), (2) October 2009 with land-use data in 2000 (meteorological condition change effect) and (3) October 2009 with land-use data in 2009 (both the effects of land-use and meteorological condition change). According to the experiment results, the change of land-use and meteorological condition by urbanization over a decade showed different contribution to the change of heat environment in Seoul metropolitan area. There was about $1^{\circ}C$ increase in near-surface (2 m) temperature over all of the analyzed stations due to meteorological condition change. In stations where the land-use type changed into urban, large temperature increase at nighttime was observed by combined effects of meteorological condition and land-use changes (maximum $4.23^{\circ}C$). Urban heat island (UHI) over $3^{\circ}C$ (temperature difference between Seoul and Okcheon) increased 5.24% due to the meteorological condition change and 26.61% due to the land-use change. That is, land-use change turned out to be contributing to the strengthening of UHI more than the meteorological condition change. Moreover, the land-use change plays a major role in the increase of sensible heat flux and decrease of latent heat flux.

• 대한산업공학회지
• /
• 제24권3호
• /
• pp.367-379
• /
• 1998

This paper considers two modes of partially accelerated life tests for items having Weibull lifetime distributions. In a use-to-acclerated mode each item is first run at use condition and, if it does not fail for a specified time, then it is run at accelerated condition until a predetermined censoring time. In an accelerated-to-use mode each one is first run at accelerated condition and, if it does not fail for a specified time, then it is run at use condition. Maximum likelihood estimators of the parameters of the lifetime distribution at use condition, and the 'acceleration factor' are obtained. The stress change time for each mode is determined to minimize the asymptotic variance of the acceleration factor, and the two modes are compared. For selected values of the design parameters the optimum plans are obtained, and the effects of the incorrect pre-estimates of the design parameters are investigated. Minimizing the generalized asymptotic variance of the estimators of the model parameters is also considered as an optimality criterion.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
• /
• pp.1291-1296
• /
• 2000

A basis for the direct use of data from nondestructive evaluation methods in bridge management systems is presented. Bridge management systems use integer-valued condition ratings to recognize conditions of bridge elements, to model progression of deterioration, and to determine repair needs. Data from nondestructive evaluation methods can inform management systems on the extent of damage, on the initiation of deterioration processes, and on the exposure of bridge elements to aggressive agents. In addition, data obtained through nondestructive evaluation methods allow the formation of models of specific deterioration process. The use of these data in bridge management systems requires redefinition of condition ratings together with the creation of procedures for automated interpretation of data. By these action, nondestructive evaluation methods are directly used to assign condition ratings, and condition ratings are made into terse form of NDE data that are compatible with present day bridge management systems. This paper reports work in progress to strategic use of nondestructive evaluation methods in bridge management system.

• 한국기계가공학회지
• /
• 제11권1호
• /
• pp.26-32
• /
• 2012

Polishing is one of the important methods in manufacturing of Si wafers and in thinning of completed device wafers. This study will report the characteristic of wafer according to processing time, machining speed and pressure which have major influence on the abrasion of Si wafer polishing. It is possible to evaluation of wafer abrasion by load cell and infrared temperature sensor. The characteristic of wafer surface according to processing condition is selected to use a result data that measure a pressure, machining speed, and the processing time. This result is appeared by the characteristic of wafer surface in machining condition. Through that, the study cans evaluation a wafer characteristic in variable machining condition. It is important to obtain optimal condition. Thus the optimum condition selection of ultra precision Si wafer polishing using load cell and infrared temperature sensor. To evaluate each machining factor, use a data through each sensor. That evaluation of abrasion according to variety condition is selected to use a result data that measure a pressure, machining speed, and the processing time. And optimum condition is selected by this result.

• 한국디지털건축인테리어학회논문집
• /
• 제9권2호
• /
• pp.35-43
• /
• 2009

The purpose of this study is to know the way of practical space use and user behavior pattern at the livingroom of city apartment that is the representative residential space of modern citizen. The way of study is to compare the livingroom of model house with actual condition of livingroom, through this way, we will know that livingroom is in use as the original concept of design or not. From the research which sees consequently (1) Most of the current model houses show common kind of livingroom by using typical style and arrangement of furniture (TV, couch, table, and decorations such as pictures or other artworks). (2) Actual condition of livingroom is different from model house in furniture arrangement and in using space which is set depending on the residents' preferences and characteristics.(computer, desk, exercising equipments, and instruments etc.) (3) The actual condition of livingroom shows the various behavior pattern of space use as the actual condition of livingroom is a mixture of typical kind of livingroom and the livingroom that reflects the characteristics of residents'.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
• /
• pp.1180-1183
• /
• 2003

170kV GIS(Gas Insulated Switchgear) is widely used in large industrial factory-electrical facilities of private use because has many benefits. But Other equipments's failures are occurred by GIS failures and give rise economic problems to user. Therefore we will examine the actual condition of the 170kV GIS-electrical facilities of private use and are able to confirm the distribution characteristic analysis of disconnecting switchgear. In this paper, we presents the actual condition investigation of the disconnecting switchgear of 170kV GIS-electrical facilities of private use by post - failure pattern, inspection method, test equipments and so forth.

• 한국의류학회지
• /
• 제38권6호
• /
• pp.913-928
• /
• 2014

This study estimated a dual path model to predict consumers' intention to use a QR code virtual store by the effect of a mobile transaction system and a facilitating condition that also examined the role of experience and the use of an intention model in the context of a QR code virtual store. A longitudinal field study was conducted at selected QR code virtual stores. A questionnaire containing mobile transaction system, facilitating condition, performance expectancy, effort expectance, and intention to use was administered at two different points in time: Initial use (T1) and the second use after one month (T2). This study sampled 109 subjects who voluntarily participated in field studies twice at different time points (pooled sample=218). Participants were asked to visit at the QR code virtual store and undertake shopping tasks on their smartphones. The estimated dual path model showed that a mobile transaction system had a positive effect on performance expectancy, which influenced intention to use; however, facilitating condition had a positive effect on effort expectancy, but the effort expectance did not lead to intention to use. The effort expectance significantly also affected the performance expectance influencing intention to use QR code virtual stores. It was also found that use experience moderated the effect of mobile transaction systems on performance expectancy. The findings discussed a critical and success factor in consumer technology acceptance and use over time. A managerial implication was also discussed to capture potential users by emphasizing performance expectancy with the superiority of an innovative system or consumer facilitating condition as external resources in the introduction stage of new technology.

• Korean Journal of Mathematics
• /
• 제17권1호
• /
• pp.53-66
• /
• 2009

We show the existence of a nontrivial periodic solution for the superquadratic parabolic equation with Dirichlet boundary condition and periodic condition with a superquadratic nonlinear term at infinity which have continuous derivatives. We use the critical point theory on the real Hilbert space $L_2({\Omega}{\times}(0 2{\pi}))$. We also use the variational linking theorem which is a generalization of the mountain pass theorem.

• 교육시설
• /
• 제13권3호
• /
• pp.6-16
• /
• 2006

The purpose of the study is on offer present condition of School Facilities for Local Residents in Daegu City. This study made progress within the scope of twenty-four public schools excepting one private school and five schools refused request. but opening present condition of the equipment was stopping in negative opening more than thing that is seen in present condition(to be a hall, a computer, swimming pool, physical education market, clearinghouse, art thread, library, language study thread) of two locals that show in old research. As result that diagnose this research, The school facilities open every schools excepting three schools could not open on account of establishment of sprinkler, residents protest about noise, small playground. The opening equipment was limited the playground, hall, basketball court, Badminton court, parking lot, classroom, library. And The use present condition was used by parking, walk, jogging and light exercise, basketball, badminton, state examination, sports meeting, books inspection, early stage soccer. When local residents require equipment use, it is not negative attitude in school but have active carriage. and Must consider plan that raise practical use degree so that can use school equipment.

• 교육시설
• /
• 제16권4호
• /
• pp.79-88
• /
• 2009

To enhance the administrational efficiency and for university facility and space management to be public, this research suggests a competent and an objective evaluation system and index. The study will assist national and university finances to contribute towards advanced education. Furthermore, figure out the space management condition of national university by utilizing the evaluation system, and through that suggesting efficient special management method. According to the result of this study, evaluation system for university facility can be widely divided into seven categories; system preparation, members conference, propriety of space allocation, propriety of management system, space use ratio, time control of space use, imposition index of surplus use. Based on these subdivisions, the space management category contains 19 evaluation items and the marking system allows perfect score of 100 points. In result of examining space management condition using the evaluation system, space management was well enforced in research focused university group where as in education centered university group, it shows relatively low enforcement. It also illustrated that efforts of evaluation items were required in categories of imposition index of surplus use and special use ratio in order for efficient space management.