• Title/Summary/Keyword: Design Evaluation

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Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2013 (설비공학 분야의 최근 연구 동향 : 2013년 학회지 논문에 대한 종합적 고찰)

  • Lee, Dae-Young;Kim, Sa Ryang;Kim, Hyun-Jung;Kim, Dong-Seon;Park, Jun-Seok;Ihm, Pyeong Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.26 no.12
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    • pp.605-619
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    • 2014
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2013. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of fluid machinery, pipes and relative parts including orifices, dampers and ducts, fuel cells and power plants, cooling and air-conditioning, heat and mass transfer, two phase flow, and the flow around buildings and structures. Research issues dealing with home appliances, flows around buildings, nuclear power plant, and manufacturing processes are newly added in thermal and fluid engineering research area. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results for general analytical model for desiccant wheels, the effects of water absorption on the thermal conductivity of insulation materials, thermal properties of Octadecane/xGnP shape-stabilized phase change materials and $CO_2$ and $CO_2$-Hydrate mixture, effect of ground source heat pump system, the heat flux meter location for the performance test of a refrigerator vacuum insulation panel, a parallel flow evaporator for a heat pump dryer, the condensation risk assessment of vacuum multi-layer glass and triple glass, optimization of a forced convection type PCM refrigeration module, surface temperature sensor using fluorescent nanoporous thin film. In the area of pool boiling and condensing heat transfer, researches on ammonia inside horizontal smooth small tube, R1234yf on various enhanced surfaces, HFC32/HFC152a on a plain surface, spray cooling up to critical heat flux on a low-fin enhanced surface were actively carried out. In the area of industrial heat exchangers, researches on a fin tube type adsorber, the mass-transfer kinetics of a fin-tube-type adsorption bed, fin-and-tube heat exchangers having sine wave fins and oval tubes, louvered fin heat exchanger were performed. (3) In the field of refrigeration, studies are categorized into three groups namely refrigeration cycle, refrigerant and modeling and control. In the category of refrigeration cycle, studies were focused on the enhancement or optimization of experimental or commercial systems including a R410a VRF(Various Refrigerant Flow) heat pump, a R134a 2-stage screw heat pump and a R134a double-heat source automotive air-conditioner system. In the category of refrigerant, studies were carried out for the application of alternative refrigerants or refrigeration technologies including $CO_2$ water heaters, a R1234yf automotive air-conditioner, a R436b water cooler and a thermoelectric refrigerator. In the category of modeling and control, theoretical and experimental studies were carried out to predict the performance of various thermal and control systems including the long-term energy analysis of a geo-thermal heat pump system coupled to cast-in-place energy piles, the dynamic simulation of a water heater-coupled hybrid heat pump and the numerical simulation of an integral optimum regulating controller for a system heat pump. (4) In building mechanical system research fields, twenty one studies were conducted to achieve effective design of the mechanical systems, and also to maximize the energy efficiency of buildings. The topics of the studies included heating and cooling, HVAC system, ventilation, and renewable energies in the buildings. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which can improve the energy efficiency of the buildings. (5) The field of architectural environment is mostly focused on indoor environment and building energy. The main researches of indoor environment are related to infiltration, ventilation, leak flow and airtightness performance in residential building. The subjects of building energy are worked on energy saving, operation method and optimum operation of building energy systems. The remained studies are related to the special facility such as cleanroom, internet data center and biosafety laboratory. water supply and drain system, defining standard input variables of BIM (Building Information Modeling) for facility management system, estimating capability and providing operation guidelines of subway station as shelter for refuge and evaluation of pollutant emissions from furniture-like products.

The Effects of Self-Congruity and Functional Congruity on e-WOM: The Moderating Role of Self-Construal in Tourism (중국 관광객의 온라인 구전에 대한 자아일치성과 기능일치성의 효과: 자기해석의 조절효과를 중심으로)

  • Yang, Qin;Lee, Young-Chan
    • The Journal of Information Systems
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    • v.25 no.1
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    • pp.1-23
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    • 2016
  • Purpose Self-congruity deals with the effect of symbolic value-expressive attributes on consumer decision and behavior, which is the theoretical foundation of the "non-utilitarian destination positioning". Functional congruity refers to utilitarian evaluation of a product or service by consumers. In addition, recent years, social network services, especially mobile social network services have created many opportunities for e-WOM communication that enables consumers to share personal consumption related information anywhere at any time. Moreover, self-construal is a hot and popular topic that has been discussed in the field of modem psychology as well as in marketing area. This study aims to examine the moderating effect of self-construal on the relationship between self-congruity, functional congruity and tourists' positive electronic word of mouth (e-WOM). Design/methodology/approach In order to verify the hypotheses, we developed a questionnaire with 32 survey items. We measured all the items on a five-point Likert-type scale. We used Sojump.com to collect questionnaire and gathered 218 responses from whom have visited Korea before. After a pilot test, we analyzed the main survey data by using SPSS 20.0 and AMOS 18.0, and employed structural equation modeling to test the hypotheses. We first estimated the measurement model for its overall fit, reliability and validity through a confirmatory factor analysis and used common method bias test to make sure that whether measures are affected by common-method variance. Then we tested the hypotheses through the structural model and used regression analysis to measure moderating effect of self-construal. Findings The results reveal that the effect of self-congruity on tourists' positive e-WOM is stronger for tourists with an independent self-construal compared with those with interdependent self-construal. Moreover, it shows that the effect of functional congruity on tourists' positive e-WOM becomes salient when tourists' self-construal is primed to be interdependent rather than independent. We expect that the results of this study can provide important implications for academic and practical perspective.

Evaluation Methods of Compression Index and the Coefficient of Consolidation by Back Analysis of Settlement Data (현장계측치로부터 역산한 압축지수와 압밀계수의 평가 방법)

  • Lee, Dal Won;Lim, Seong Hun;Kim, Ji Moon
    • Korean Journal of Agricultural Science
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    • v.27 no.1
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    • pp.39-47
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    • 2000
  • A large scale field test of prefabricated vertical drains is performed to analyze the effect of parameters of the very soft clay at a test site. Compression index and the coefficient of horizontal consolidation obtained by back-analysis from the settlement data were compared with those obtained by means of laboratory tests. The Hyperbolic, Asaoka's and The Curve fitting methods are used to estimate final settlements and coefficients of consolidation. 1. Final settlement predicted with the Hyperbolic method was the largest, and the settlements predicted with the Asaoka's and the Curve fitting methods were nearly the same range, and it was concluded that smear effect has to be considered on design in the case that spacing of drains is small 2. The relationships of the measured consolidation ratio (Urn) and the designed consolidation ratio($U_t$) were showed as $U_m$ = (1.13~1.17)$U_t$, $U_m$ = (1.07~1.20)$U_t$, $U_m$ = (1.13~1.17)$U_t$ on the Hyperbolic, Asaoka's and the Curve fitting methods, respectively. The relations on the Asaoka's and the Curve fitting methods were nearly the same range. 3. The relationships of the field compression index($C_{cfield}$) and virgin compression index($V_{cclab}$) were showed as $C_{cfield}$ = (1.26~1.45)$V_{cclab}$, $C_{cfield}$ = (1.08~1.15) $V_{cclab}$, $C_{cfield}$ = (1.04~1.21)$V_{cclab}$, on the Hyperbolic, Asaoka's and the Curve fitting methods, respectively. 4. The ratio ($C_h/C_v$) of the coefficient of vertical consolidation and the coefficient of horizontal consolidation that is obtained by back-analysis from the settlement data was $C_h$=(0.7~0.9)$C_v$, $C_h$=(0.9~1.5)$C_v$, $C_h$=(2.4~3.0)$C_v$ on the Hyperbolic, Asaoka's and the Curve fitting methods, respectively. 5. It was concluded that the exact consolidation coefficient must be determined after the final settlement is predicted again when the consolidation is finished, because the field consolidation coefficient is decreased as the time allowed to be alone is increased.

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Radiographic evaluation of marginal bone resorption around two types of external hex implants : preliminary study (두 종의 external hex implant의 변연골 흡수에 관한 연구 : 예비연구 (preliminary study))

  • Lee, Ji-Eun;Heo, Seong-Joo;Koak, Jai-Young;Kim, Seong-Kyun;Han, Chong-Hyun
    • The Journal of Korean Academy of Prosthodontics
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    • v.46 no.2
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    • pp.169-174
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    • 2008
  • Statement of problem: Changes of the marginal bone around dental implants have significance not only for the functional maintenance but also for the esthetic success of the implant. It was proposed that bone-retention elements such as microthreads at the coronal part of implant might help maintain the marginal bone level. Purpose: This study was designed to evaluate the effect of microthread configuration within the marginal coronal portion of the implant fixture at the marginal bone changes after loading around two different external hex implants. Material and methods: Twenty-four patients were included and randomly assigned to treatment with $Br{{\aa}}nemark$ system implants (Group 1, rough-surfaced implants, n=20) and Oneplant system implants (Group 2, rough-surfaced neck with microthreads, n=20). Clinical and radiographic examinations were conducted at baseline (implant loading) and 1 year postloading. Data analysis was performed by the SAS statistical package version 9.1.3 (SAS Institute, Cary, NC, USA) and the final model was calculated by the MIXED procedure (three-level ANCOVA) for marginal bone change of each test group at baseline and 1 year follow-up. Results: Comparing to baseline, significant differences were noted in marginal bone level changes for the 2 groups at 1 year follow-up (P<0.05). Group 1 had a mean crestal bone level changes of $0.83{\pm}0.31mm$; Group 2 had a mean crestal bone level changes of $0.44{\pm}0.36mm$. Rough-surfaced with microthreads implants showed significantly less marginal bone loss than rough surfaced neck without microthread implants. Conclusion: A rough surface with microthreads at the implant was beneficial design to maintain the marginal bone level against functional loading.

An Investigation into the Secondary Science Teachers' Perception on Scientific Models and Modeling (과학적 모델과 모델링에 대한 중등 과학 교사의 인식 탐색)

  • Cho, Eunjin;Kim, Chan-jong;Choe, Seung-urn
    • Journal of The Korean Association For Science Education
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    • v.37 no.5
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    • pp.859-877
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    • 2017
  • The purpose of this study is to probe secondary science teachers' perception on scientific models and modeling. A total of 50 experienced science teachers were surveyed with 10 open-ended questions about several aspects of models and modeling: definition, examples, purpose, multiplicity, changeability, design/construction, evaluation and beliefs in the use of models and modeling as a teaching tool. The analysis of the data shows the following results: 1) understanding of models and modeling held by a majority of experienced secondary science teachers was far from that of experts as they concentrated on a model's superficial, representative, and visual functions, 2) when it comes to their view toward the use of a model, a model does not remain in the stage of 'doing science' but in the stage of being a subsidiary teaching tool for the teacher's explaining and the students' understanding of scientific concepts, 3) the subjects they majored in made meaningful differences in their contextual understanding of models and modeling, 4) though most of the teachers acknowledged the importance of teaching about models and modeling, even a lot of them showed a negative position toward the opinion that they are willing to apply modeling to their classes. Implications of the results were discussed in terms of intervention in order to enhance secondary science teachers' understanding and pedagogical content knowledge of models and modeling.

Derivation of rock parameters from Televiewer data (텔레뷰어에 의한 토목설계 매개변수의 산출)

  • Kim Jung-Yul;Kim Yoo-Sung
    • 한국지구물리탐사학회:학술대회논문집
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    • 1999.08a
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    • pp.137-155
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    • 1999
  • Recently, Televiewer(Borehole Acoustic Scanner(Televiewer)) has come to be widely used specially for the general engineering construction design. The Televiewer tool using a focussed acoustic beam is to detect the amplitude and traveltime of each reflected acoustic signal at the wall, resulting in the amplitude- and traveltime image respectively. Fractures can be well detected, because they easily scatter the acoustic energy due to the highly narrow beam. In addition, the drilling work will rough the borehole wall so that the acoustic energy can be scattered simply due to the roughness of the wall. Thus, the amplitude level can be directed associated with the elastic properties(impedance) and the hardness of the rock as well. Meanwhile, the traveltime image provides an information about the borehole shape and can be converted to a high precision 3D caliper log(max. 288 arms). In this paper, based on the high resolution of Televiewer images, general evaluation methods are illustrated to derive very reliable rock parameters.

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Optimization of Cookie Preparation by Addition of Yam Powder (마분말 첨가 쿠키 제조조건 최적화)

  • Joo, Na-Mi;Lee, Sun-Mee;Jung, Hee-Sun;Park, Sang-Hyun;Song, Yun-Hee;Shin, Ji-Hun;Jung, Hyeon-A
    • Food Science and Preservation
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    • v.15 no.1
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    • pp.49-57
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    • 2008
  • This study was conducted to develop an optimal composite recipe for a cookie including yam powder that would be attractive to all age groups. Wheat flour was partially substituted by yam powder to reduce the content of wheat flour. This study has produced the sensory optimal composite recipe by making cookies, respectively with each 5 level of yam powder $(X_1)$, Sugar$(X_2)$, butter$(X_3)$, by C.C.D (Central Composite Design) and conducting sensory evaluation and instrumental analysis by means of RSM (Response Surface Methodology). Sensory items showed very significant values in color, softness, overall quality (p<0.01), flavor (p<0.05) and those of instrumental analysis showed significant values in lightness, redness (p<0.05), spread ratio, hardness (p<0.01). Also sensory optimal ratio of yam cookie was calculated at yam powder 37.35 g, sugar 50.75 g, butter 78.40 g and it was revealed that the factors of influencing yam cookie aptitude were in older of yam powder, butter, sugar.

Effects of Feeding Whole-Crop Barley Silage and Corn Silage on Nutrients Availability, Growth Performance and Blood Parameters in Korean Black Goats (청보리사일리지 및 옥수수사일리지 급여가 육성기 재래 흑염소의 영양소 이용률, 성장 및 혈액성상에 미치는 영향)

  • Park, Min-Ki;Jo, Ik-Hwan;HwanBo, Soon;Ahn, Jong-Ho
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.31 no.4
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    • pp.441-450
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    • 2011
  • This study examined the effects of feeding whole-crop barley silage (BS), corn silage (CS) and the mixture of BS and CS (CB) on feed consumption, daily gain, nutrients apparent digestibilities and blood parameters in order to investigate the feed evaluation in Korean black goats. BS, CS, and CB were fed to twelve Korean black goats, which were allocated into three groups in metabolic cages according to the latin-square design. As a result, dry and organic matter intakes for goats per day have shown a tendency to decrease in the order of CS, CB and BS, but there were no significant differences. We also found a similar tendency when the intakes of crude protein, crude fat, and non-fiber carbohydrates (NFC) were examined. However, ADF and NDF consumptions showed a decreasing tendency in the order of CB, BS and CS. Dry matter intakes per metabolic body weight showed the decreasing tendency in the order of CS (57.6g), CB (53.8g) and BS (52.7g), however with no statistical differences. Average daily gain of 64.2 g in CB was significantly higher than the other groups (42.0g to 46.0g). Nitrogen intakes and nitrogen retention showed a decreasing tendency in the order of CS, CB and BC. Nevertheless, nitrogen retention in CS group was higher by 30% than that of the BC group with p<0.05. Apparant digestibilities of dry and organic matters were 72.6 and 72.8% for the CS group respectively, which were significantly higher than those of the BS group (67.5 and 69.0%) and the CB group (66.0 and 67.1%). In conclusion, the results of this study demonstrated that the CS group showed more positive feed consumption, digestibility, and nitrogen retention in Korean black goats than those of BS group. The CB group, however, showed similar results to the results of the CS group.

Development and Analyses of Effects of ICT Teaching: Learning Process Plan for 'Designing My Home' unit of Technology.Home Economic in High School (ICT활용 교수.학습 과정안 개발 및 효과 분석: 고등학교 기술.가정 "나의 주거 공간꾸미기" 단원을 중심으로)

  • Park Hyun-Sook;Cho Jae-Soon
    • Journal of Korean Home Economics Education Association
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    • v.18 no.2 s.40
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    • pp.15-27
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    • 2006
  • The purpose of this research was to develop and analyze the effects of ICT based teaching learning process plans for 'Designing My Home' unit of Technology Home Economics subject in High School. The seven housing contents were selected from 8 textbooks and 8 teaching resources at the analyses stage. A specific homepage(ieduhome.cafe.com) was built to utilize the eight ICT teaching learning process plan as well as many other resources at the planning & development stages. The number of 68 highschool students have participated for the application stage during September 4-26, 2003 and the same number have studied the same contents through regular teaching learning plans as a comparison group. Experimental groups have significantly more increased in the knowledge and understanding of the housing contents than have comparison groups. The same results occurred in the interests in Home Economics, Housing, and Internet utilized study. The Design reports were not statistically differed between two groups based on the objective evaluation criteria. The results of this study generally supported previous research and showed that the In teaching learning plans were more effective in various aspects than were the regular plans.

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Development and Application of Home Economics Teacher Training Program for Elevating The Recognition of Han Culture - Based on Clothing Life Culture in Three Kingdoms Period - (한(韓)문화 인식 증진을 위한 가정과교사 연수 프로그램의 개발 및 적용 - 의생활 문화 영역 삼국 시대 복식을 중심으로 -)

  • Bae, Hyun-Young;Park, Mi-Jeong;Lee, Hye-Ja
    • Journal of Korean Home Economics Education Association
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    • v.22 no.1
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    • pp.33-50
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    • 2010
  • This study was conducted as a preparation for the operation of 2007 revised curriculum and an effort towards professional development for Home Economics teachers in clothing life culture area. The aim of this study was to develop an teacher training program based on the clothing life culture in three kingdoms period, apply it to teacher training, and evaluate the program by analyzing the purpose of participation, trainee expectation and gratification, change of recognition level about Han culture, trainee satisfaction, and willingness to apply to teaching and attend further training program. The characteristic of the training program was that it consisted of both highly qualified lectures on professional contents and practices with school classroom level, and it dealt with the ancient korean clothing as its central subject. The purpose of the training program was to elevate the recognition of Han culture and increase the possibility of application in the classroom situation. It showed that the trainees participated with high intrinsic motivations, aiming to improve their professionalism in subject content and expecting various subject content. It also showed that the trainee gratification was very high in professional knowledge of clothing culture area, and the trainees were gratified in most evaluation items. As to the recognition level of korean culture, even before the training program, it was generally higher than average. After the program, it increased meaningfully. Through the training program, the trainees became feel prouder of Han culture and people and themselves as Home economics teachers. The contents of the program were considered very helpful for the improvement of professionalism and the design of instruction and learning activity. It was revealed that Home Economics teachers had very high expectations of the development of instruction-learning models which could enable them to experience new and interesting ideas, help enhance their professionalism, and be applied to their teaching. Therefore, continuous development and operation of the teacher training program relating to the life culture such as clothing, food, and housing life are needed.

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