• Title/Summary/Keyword: Hall factor

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A study on the Properties of $In_{l-x}Ga_{x}As$ Grown by the TGS Methods (TGS법으로 성장한 $In_{l-x}Ga_{x}As$의 특성에 관한 연구)

  • Lee, W.S.;Moon, D.C.;Kim, S.T.;Suh, Y.S.
    • Proceedings of the KIEE Conference
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    • 1988.11a
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    • pp.372-375
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    • 1988
  • The III-V ternary alloy semiconductor $In_{l-x}Ga_{x}As$ were grown by the temperature Gradient of $0.60{\leq}x{\leq}0.98$. The electrical properties were investigated by the Hall effect measurement with the Van der Pauw method in the temperature range of $90{\sim}300K$. $In_{l-x}Ga_{x}As$ were revealed n-type and the carrier concentration at 300K were in the range of $9.69{\times}10^{16}cm^{-3}{\sim}7.49{\times}10^{17}cm^{-3}$. The resistivity was increased and the carrier mobility was decreased with increasing the composition ratio. The optical energy gap determined by optical transmission were $20{\sim}30meV$ lower than theoretical valves on the basis of absorption in the conduction band tail and it was decreased with increasing the temperature by the Varshni rule. In the photoluminescence of undoped $In_{l-x}Ga_{x}As$ at 20K, the main emission was revealed by the radiative recombination of shallow donor(Si) to acceptor(Zn) and the peak energy was increased with increasing the composition, X. The diffusion depth of Zn increases proportionally with the square root of diffusion time, and the activation energy for the Zn diffusion into $In_{0.10}Ga_{0.90}As$ was 2.174eV and temperatures dependence of diffusion coefficient was D = 87.29 exp(-2.174/$K_{B}T$). The Zn diffusion p-n $In_{x}Ga_{x}As$ diode revealed the good rectfying characteristics and the diode factor $\beta{\approx}2$. The electroluminescence spectrum for the Zn-diffusion p-n $In_{0.10}Ga_{0.90}As$ diode was due to radiative recombation between the selectron trap level(${\sim}140meV$) and Zn acceptor level(${\sim}30meV$). The peak energy and FWHM of electroluminescence spectrum at 77K were 1.262eV and 81.0meV, respectively.

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Active and Cognitive Evaluating of the Recreational Spaces in Natural Settings (자연휴양공간(自然休養空間)의 이용행동(利用行動) 및 인지적(認知的) 평가(評價))

  • Kim, Bum Soo;Chung, Yoon Soo
    • Journal of Korean Society of Forest Science
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    • v.83 no.4
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    • pp.429-440
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    • 1994
  • This study attempt to evaluate the recreation space(two patterns ; one is open space ; forest, water-front space and free open space, the other recreational fercilities) located in the natural area based on clarifying the relationship between the physical conditions of these spaces and human response(users' cognitive evaluation and users' activity pattern). On this standpoint it was proceeded to analyses of the information which was collected by interviews to users who were in this open space at the natural park of Osaka Prefecture. Through this study, the results were summarized as follows ; 1) Forest and waterfront space are considered to be a basic factor of the composition in natural recreation areas. There was difference on the recreational value depending on condition of forest composition. The hardwood-forest apparently high in its efficiency. 2) Free open space is a definite recreational space surely wide in its scope of active of recreational use. The site should be setted up considering the plants conditions around and geographical features according to the recreational activities, and the ground cover should be well controlled. 3) The recreational facilities in natural settings such as the sightseeing tower, the insect display hall, and the camp site appeared to produce low value as a recreational space. It was desirable that recreational activities be allowed within the scope. Consequently, we should carefully consider environmental capacity and landscape to designing these spaces 4) Traditional history and cultural properties are recognized as part of recreational resource as and also as essence of the compositions. So continuos care and proportion of history and cultural properties should be guaranteed.

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Factors Influencing the Depression of Aged People (노인 우울에 미치는 요인)

  • Lee, Eun-Ryeong;Kang, Ji-Hyuk;Jung, Jae-Pil
    • The Journal of the Korea Contents Association
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    • v.13 no.7
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    • pp.290-300
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    • 2013
  • The purpose of this research is to examine the influence to physical health status, economic status, family support, social support and self-esteem which affects to solve depression, and give basic information for developing a program to prevent the aged people gloominess and a way to solve that gloominess. This surveying study was undertaken through personal interview way for 357 aged people who were in the elder's meeting hall, living in elderly welfare institude, or home near Gumi, Gimcheon, and Chilgok regions. For data analysis, SPSS/PC 18.0 and AMOS 18.0 program for frequency analysis, First, In the reason of depression by general distinctive quality, there was a significant difference in sex'educational background'existance of a spouse of the condition of living-together, and personal health condition. Second, affecting factors to religious life were economic condition, family support, and self-esteem. Third, the most serious factor that enhanced depression was physical health. Fourth, It appeared as higher attendence of indivisuals about religion means decrease of the depression. When these result reviewed, to control the depression of aged people, it is necessary to develop and conduct a total program that can detect and manage depression early through measuring the physical health, family support, social support and self-esteem. Especially, participation of religious life is considered to ameliorate the depression of aged people and help them live a good senescence.

An Analysis and Improvement of Free Form Building's Construction Productivity - Focused on Exposed Concrete Work - (비정형 건축물 공사의 생산성 분석 및 향상방안 - 노출콘크리트 공사를 중심으로 -)

  • Lee, Eun-Young;Kim, Yea-Sang
    • Korean Journal of Construction Engineering and Management
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    • v.15 no.3
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    • pp.38-46
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    • 2014
  • The Global's top five Design Firms selected from BauNetz a German architectural magazine in 2007 designed free form building design which was 25% of the overall design by 2006-2010. Free form building is a landmark of the city and the country so its social and economic impacts are very large. In case of Korea, free form buildings such as Tribowl in Incheon, KINTEX Exhibition hall 2 and Dongdaemun Design Plaza have increased. However, those the increase in design trends and, the needs due to the lack of free form building design and construction management experience, free form building projects can't be expected to profitability and have a number of problems after completion. Especially, there are many excessive quality problems and the rising cost due to design changes frequently and lack of experience and data. Thus an initial plan regardless of considering of free form building's characteristics can be a huge risk because of the difference with the plan and actual projects, yet there aren't free form building project's performance data and case studies related to productivity. In this study, through selection of low-construction productivity works and an analysis of the work process and productivity data, hope to propose an actual field productivity of free form building and the ways to improve productivity.

Preparation of Bismuth Telluride Thin Films using RF magnetron sputtering and Study on Their Thermoelectric Properties (RF 마그네트론 스퍼터링을 이용한 Bismuth Telluride 박막의 제조와 그 열전 특성 연구)

  • Kim, Dong-Ho;Lee, Gun-Hwan
    • Journal of the Korean Vacuum Society
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    • v.14 no.4
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    • pp.215-221
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    • 2005
  • Thermoelectric bismuth telluride thin films were prepared on $SiO_{2}$/Si substrate with co-sputtering of bismuth and tellurium targets. The effects of deposition temperature on surface morphology, crystallinity and electrical transport properties were investigated. Hexagonal crystallites were clearly visible at the surface of films deposited above $290 ^{\circ}C$. Change of dominant phase from rhombohedral $Bi_2Te_3$ to hexagonal BiTe was confirmed with X-ray diffraction analysis. The deviation from stoichiometric composition at high deposition temperature resulted in the change of structural and electrical characteristics. Seebeck coefficients of all samples have negative value, indicating the prepared $Bi_XTe_Y$ films are n-type thermoelectric. Optimum of Seebeck coefficient and power factor were obtained at the deposition temperature of $225 \^{circ}$C (about -55 $\mu$V/K and $3\times10^{-4}$ W/$k^{2}$m, respectively). Deterioration of thermoelectric properties at higher temperature.

A Study on the Effect of Booth Recommendation System on Exhibition Visitors Unplanned Visit Behavior (전시장 참관객의 계획되지 않은 방문행동에 있어서 부스추천시스템의 영향에 대한 연구)

  • Chung, Nam-Ho;Kim, Jae-Kyung
    • Journal of Intelligence and Information Systems
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    • v.17 no.4
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    • pp.175-191
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    • 2011
  • With the MICE(Meeting, Incentive travel, Convention, Exhibition) industry coming into the spotlight, there has been a growing interest in the domestic exhibition industry. Accordingly, in Korea, various studies of the industry are being conducted to enhance exhibition performance as in the United States or Europe. Some studies are focusing particularly on analyzing visiting patterns of exhibition visitors using intelligent information technology in consideration of the variations in effects of watching exhibitions according to the exhibitory environment or technique, thereby understanding visitors and, furthermore, drawing the correlations between exhibiting businesses and improving exhibition performance. However, previous studies related to booth recommendation systems only discussed the accuracy of recommendation in the aspect of a system rather than determining changes in visitors' behavior or perception by recommendation. A booth recommendation system enables visitors to visit unplanned exhibition booths by recommending visitors suitable ones based on information about visitors' visits. Meanwhile, some visitors may be satisfied with their unplanned visits, while others may consider the recommending process to be cumbersome or obstructive to their free observation. In the latter case, the exhibition is likely to produce worse results compared to when visitors are allowed to freely observe the exhibition. Thus, in order to apply a booth recommendation system to exhibition halls, the factors affecting the performance of the system should be generally examined, and the effects of the system on visitors' unplanned visiting behavior should be carefully studied. As such, this study aims to determine the factors that affect the performance of a booth recommendation system by reviewing theories and literature and to examine the effects of visitors' perceived performance of the system on their satisfaction of unplanned behavior and intention to reuse the system. Toward this end, the unplanned behavior theory was adopted as the theoretical framework. Unplanned behavior can be defined as "behavior that is done by consumers without any prearranged plan". Thus far, consumers' unplanned behavior has been studied in various fields. The field of marketing, in particular, has focused on unplanned purchasing among various types of unplanned behavior, which has been often confused with impulsive purchasing. Nevertheless, the two are different from each other; while impulsive purchasing means strong, continuous urges to purchase things, unplanned purchasing is behavior with purchasing decisions that are made inside a store, not before going into one. In other words, all impulsive purchases are unplanned, but not all unplanned purchases are impulsive. Then why do consumers engage in unplanned behavior? Regarding this question, many scholars have made many suggestions, but there has been a consensus that it is because consumers have enough flexibility to change their plans in the middle instead of developing plans thoroughly. In other words, if unplanned behavior costs much, it will be difficult for consumers to change their prearranged plans. In the case of the exhibition hall examined in this study, visitors learn the programs of the hall and plan which booth to visit in advance. This is because it is practically impossible for visitors to visit all of the various booths that an exhibition operates due to their limited time. Therefore, if the booth recommendation system proposed in this study recommends visitors booths that they may like, they can change their plans and visit the recommended booths. Such visiting behavior can be regarded similarly to consumers' visit to a store or tourists' unplanned behavior in a tourist spot and can be understand in the same context as the recent increase in tourism consumers' unplanned behavior influenced by information devices. Thus, the following research model was established. This research model uses visitors' perceived performance of a booth recommendation system as the parameter, and the factors affecting the performance include trust in the system, exhibition visitors' knowledge levels, expected personalization of the system, and the system's threat to freedom. In addition, the causal relation between visitors' satisfaction of their perceived performance of the system and unplanned behavior and their intention to reuse the system was determined. While doing so, trust in the booth recommendation system consisted of 2nd order factors such as competence, benevolence, and integrity, while the other factors consisted of 1st order factors. In order to verify this model, a booth recommendation system was developed to be tested in 2011 DMC Culture Open, and 101 visitors were empirically studied and analyzed. The results are as follows. First, visitors' trust was the most important factor in the booth recommendation system, and the visitors who used the system perceived its performance as a success based on their trust. Second, visitors' knowledge levels also had significant effects on the performance of the system, which indicates that the performance of a recommendation system requires an advance understanding. In other words, visitors with higher levels of understanding of the exhibition hall learned better the usefulness of the booth recommendation system. Third, expected personalization did not have significant effects, which is a different result from previous studies' results. This is presumably because the booth recommendation system used in this study did not provide enough personalized services. Fourth, the recommendation information provided by the booth recommendation system was not considered to threaten or restrict one's freedom, which means it is valuable in terms of usefulness. Lastly, high performance of the booth recommendation system led to visitors' high satisfaction levels of unplanned behavior and intention to reuse the system. To sum up, in order to analyze the effects of a booth recommendation system on visitors' unplanned visits to a booth, empirical data were examined based on the unplanned behavior theory and, accordingly, useful suggestions for the establishment and design of future booth recommendation systems were made. In the future, further examination should be conducted through elaborate survey questions and survey objects.

System Development for Measuring Group Engagement in the Art Center (공연장에서 다중 몰입도 측정을 위한 시스템 개발)

  • Ryu, Joon Mo;Choi, Il Young;Choi, Lee Kwon;Kim, Jae Kyeong
    • Journal of Intelligence and Information Systems
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    • v.20 no.3
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    • pp.45-58
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    • 2014
  • The Korean Culture Contents spread out to Worldwide, because the Korean wave is sweeping in the world. The contents stand in the middle of the Korean wave that we are used it. Each country is ongoing to keep their Culture industry improve the national brand and High added value. Performing contents is important factor of arousal in the enterprise industry. To improve high arousal confidence of product and positive attitude by populace is one of important factor by advertiser. Culture contents is the same situation. If culture contents have trusted by everyone, they will give information their around to spread word-of-mouth. So, many researcher study to measure for person's arousal analysis by statistical survey, physiological response, body movement and facial expression. First, Statistical survey has a problem that it is not possible to measure each person's arousal real time and we cannot get good survey result after they watched contents. Second, physiological response should be checked with surround because experimenter sets sensors up their chair or space by each of them. Additionally it is difficult to handle provided amount of information with real time from their sensor. Third, body movement is easy to get their movement from camera but it difficult to set up experimental condition, to measure their body language and to get the meaning. Lastly, many researcher study facial expression. They measures facial expression, eye tracking and face posed. Most of previous studies about arousal and interest are mostly limited to reaction of just one person and they have problems with application multi audiences. They have a particular method, for example they need room light surround, but set limits only one person and special environment condition in the laboratory. Also, we need to measure arousal in the contents, but is difficult to define also it is not easy to collect reaction by audiences immediately. Many audience in the theater watch performance. We suggest the system to measure multi-audience's reaction with real-time during performance. We use difference image analysis method for multi-audience but it weaks a dark field. To overcome dark environment during recoding IR camera can get the photo from dark area. In addition we present Multi-Audience Engagement Index (MAEI) to calculate algorithm which sources from sound, audience' movement and eye tracking value. Algorithm calculates audience arousal from the mobile survey, sound value, audience' reaction and audience eye's tracking. It improves accuracy of Multi-Audience Engagement Index, we compare Multi-Audience Engagement Index with mobile survey. And then it send the result to reporting system and proposal an interested persons. Mobile surveys are easy, fast, and visitors' discomfort can be minimized. Also additional information can be provided mobile advantage. Mobile application to communicate with the database, real-time information on visitors' attitudes focused on the content stored. Database can provide different survey every time based on provided information. The example shown in the survey are as follows: Impressive scene, Satisfied, Touched, Interested, Didn't pay attention and so on. The suggested system is combine as 3 parts. The system consist of three parts, External Device, Server and Internal Device. External Device can record multi-Audience in the dark field with IR camera and sound signal. Also we use survey with mobile application and send the data to ERD Server DB. The Server part's contain contents' data, such as each scene's weights value, group audience weights index, camera control program, algorithm and calculate Multi-Audience Engagement Index. Internal Device presents Multi-Audience Engagement Index with Web UI, print and display field monitor. Our system is test-operated by the Mogencelab in the DMC display exhibition hall which is located in the Sangam Dong, Mapo Gu, Seoul. We have still gotten from visitor daily. If we find this system audience arousal factor with this will be very useful to create contents.

A Study on the Influence of the Water System on the Location and Spatial Structure of Hongju-seong (수체계가 홍주성의 입지와 공간구조 변천과정에 미친 영향)

  • Lee, Kyung-Chan;Kang, In-Ae
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.38 no.4
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    • pp.12-24
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    • 2020
  • The purpose of this study is to analyze the influence of the water system on the location, spatial structure, and construction method of Hongju-eupseong, centering on Hongjumok-eupchi. During the Joseon Dynasty, the water system in Hongjumok-eupchi is composed of artificially constructed Seong-an Runnel and ponds based on a branch-shaped natural waterways flowing from south to north and west to east. Compiling the results of various literature records, excavations and analysis of map data, it can be seen that the water system has an important influence on the construction of Hongju-seong. Firstly, Hongju-seong from the Goryeo Dynasty to the late Joseon Dynasty is located using a circular shape of topographical structure and a small erosion basin formed on the inner side of the Hongseongcheon and Wolgyecheon streams without significant change in location. In particular, Wolgyecheon and Hongseongcheon are natural moats, which are harmonized with Sohyangcheon and riverside topographical structures, affecting the location and construction method of Hongju-seong, water related facilities, and the spatial structure of eupseong. It is understood that location characteristic of Hongju-seong reflects the urban location structure harmonized with waterways in ancient China and Korea. Secondly in harmony with the water system and topographic structure of Hongju-seong, it is an important factor in deciding the land use of the town, the arrangement of the town hall facilities and inducing various non-subsidiary measures such as the establishment of embankment forest with a secret function and the closure of the south gate. In addition, artificial drainage facilities such as Seongan runnel and ponds are being actively introduced from early on to protect the walls or towns from flooding of Wolgyecheon. Especially there were typical methods for protecting the walls from water damage such as the Joseon Dynasty stone castle structure that was integrated with saturn(soil wall) in the Goryeo Dynasty, retreating wall in the northern gate area in the late Joseon Dynasty, and the method of constructing wall using korean tile and stone floors between reinforced soil layers in the western and northern wall.