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Heat/Mass Transfer on Effusion Plate with Circular Pin Fins for Impingement/Effusion Cooling System with Intial Crossflow (초기 횡방향 유동이 존재하는 충돌제트/유출냉각에서 원형핀이 설치된 유출면에서의 열/물질전달 특성)

  • Hong Sung Kook;Rhee Dong-Ho;Cho Hyung Hee
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.29 no.7 s.238
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    • pp.828-836
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    • 2005
  • Impingement/effusion cooling technique is used for combustor liner or turbine parts cooling in gas turbine engine. In the impingement/effusion cooling system, the crossflow generated in the cooling channel induces an adverse effect on the cooling performance, which consequently affects the durability of the cooling system. In the present study, to reduce the adverse effect of the crossflow and improve the cooling performance, circular pin fins are installed in impingement/effusion cooling system and the heat transfer characteristics are investigated. The pin fins are installed between two perforated plates and the crossflow passes between these two plates. A blowing ratio is changed from 0.5 to 1.5 for the fixed jet Reynolds number of 10,000 and five circular pin fin arrangements are considered in this study. The local heat/mass transfer coefficients on the effusion plate are measured using a naphthalene sublimation method. The results show that local distributions of heat/mass transfer coefficient are changed due to the installation of pin fins. Due to the generation of vortex and wake by the pin fin, locally low heat/mass transfer regions are reduced. Moreover, the pin fin prevents the wall jet from being swept away, resulting in the increase of heat/mass transfer. When the pin fin is installed in front of the impinging let, the blockage effect on the crossflow enhances the heat/mass transfer. However, the pin fin installed just behind the impinging jet blocks up the wall jet, decreasing the heat/mass transfer. As the blowing ratio increases, the pin fins lead to the higher Sh value compared to the case without pin fins, inducing $16\%{\~}22\%$ enhancement of overall Sh value at high blowing ratio of M=1.5.

Multi-physics Modelling of Moisture Related Shrinkage in Concrete (콘크리트 수분관련 수축에 관한 다중물리모델)

  • Lee, Chang-Soo;Park, Jong-Hyok
    • Journal of the Korean Society of Hazard Mitigation
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    • v.9 no.2
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    • pp.1-9
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    • 2009
  • Water binder ratio combine high-performance concrete shrinkage of less than 0.4 to determine the transformation to a total shrinkage of water to move outside and internal consumption of moisture due to drying shrinkage and autogenous shrinkage, and then, the relative humidity changes and strain to be approached by surface physics describe the relationship between self-desiccation and autogenous shrinkage was set. To verify the self-desiccation in the humidity shrinkage and humidity measurements performed, and the research model, Tazawa, CEB-FIP model than to let the measure and the most similar results in this study based on self-desiccation model, autogenous shrinkage didn't represent the linear shrinkage by the drying shrinkage of the external moving but exponential relationships, unlike with the nature and rapid in the early age properly describes the attributes in shrinkage could see. After this research to move moisture and to reflect the shrinkage model, temperature, moisture transfer, strain analysis by multi-physics model is very similar to the results of mock-up specimen measurements performed for this research, the value measured by the internal consumption of moisture, therefore self-desiccation and a multi-physics model considering autogenous shrinkage might be relevant.

A Study of Fashion illustration Applying Formative of Folk Painting (민화의 조형적 양식을 응용한 패션 일러스트레이션 연구)

  • Lee, Ji-Soo;Chung, Eun-Sook
    • Journal of the Korean Society of Clothing and Textiles
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    • v.29 no.8 s.145
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    • pp.1057-1067
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    • 2005
  • In the modem society, people try to represent and protect their traditional arts in aesthetic way along with the global society. The proposal of this thesis is about the fashion illustration that has adopted the folklike formative arts. 1 prefer the formative character rather then the universal character and I would like to use of folk paintings far the fashion illustration. Because the formative character of folk paintings is very expressional, we are able to draw a fashion illustration in easy, new, creative and less difficult way. The fashion illustration has to be a specialized field from the formative arts, and we need to study in a new way as well. We draw fashion illustration through the understanding of folk paintings and the study of analysis in formative. As a result of this study, we could draw a fashion illustration which is very abstract, exaggerative and simple. We also could expect the free hand drawing lines on this illustration. In these fashion illustrations, the human bodies let us fret the artists' tense, speed, and power. According to the important character of folk painting, which is the beauty of color, these fashion illustrations have expressed more color intensive. In the falk paintings there is a kind of rules to make color order, so the fashion illustrations that we drew have the bright and clear color combination. Because the folk paintings shouldn't be the artistic but should be the realistic, the fashion illustrations concentrate on the real subject. It is very natural looking that use the natural dyes in the fashion illustrations. According to this kind of art task, fashion illustration will be a certain part of the illustration in the modem society.

A Study of the Status and Improvements of the National Science Fairs (현행 전국과학전람회의 실태 및 개선방안에 관한 연구)

  • 최도성;한효의
    • Journal of Korean Elementary Science Education
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    • v.20 no.1
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    • pp.59-73
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    • 2001
  • The National Science Fairs has been held in every year for the promotion of science and technology and scientific civil life. The purpose of this study is to survey the current problems in National Science Fairs by making up a question and to improve them. The study makes up a questionnaires about the existing Science Fairs to the teachers who have submitted their works to the Science Fairs and suggest the ways of improvement. The result of questionnaires is that little availability of reference materials, difficulty of paying proper attention to regular classes because of frequent travels, and absence of experimental devices and experimental rooms are perceived as major obstacles in preparing for the exhibition. Respondents teacher also pointed out some problems with the current organization of the exhibition; non-voluntary selection process for the potential authors, separation of research content from regular teaching materials, unrealistically high standard, low participation rate of teachers, so many exhibited works, lack of professionalism in the screening process. The majority however, agreed that the exhibition event should be continuously done, after remedial measures have been taken about the problems. First, the side of science education is emphasized in a purpose of the science fairs to let activity related to science fair be closely connected with school education. Second, students have to be divided according to grade. Third, research level have to be set not too higher than regular instruction content. Fourth, hand book related to science fairs have to be manufactured and spread. Fifth, data of local science fair have to be arranged. Sixth, judging section have to be subdivided and people related to science education have to be included to a judge. Seventh, excellent works have to be support to participate in ISEF.

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Automatic Pattern Setting System Reacting to Customer Design

  • Yuan, Ying;Huh, Jun-Ho
    • Journal of Information Processing Systems
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    • v.15 no.6
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    • pp.1277-1295
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    • 2019
  • With its technical development, digital printing is being universally introduced to the mass production of clothing factories. At the same time, many fashion platforms have been made for customers' participation using digital printing, and a tool is provided in platforms for customers to make designs. However, there is no sufficient solution in the production stage for automatically converting a customer's design into a file before printing other than designating a square area for the pattern designed by the customer. That is, if 30 different designs come in from customers for one shirt, designers have to do the work of reproducing the design on the clothing pattern in the same location and in the same angle, and this work requires a great deal of manpower. Therefore, it is necessary to develop a technology which can let the customer make the design and, at the same time, reflect it in the clothing pattern. This is defined in relation to the existing clothing pattern with digital printing. This study yields a clothing pattern for digital printing which reflects a customer's design in real time by matching the diagram area where a customer designs on a given clothing model and the area where a standard pattern reflects the customer's actual design information. Designers can substitute the complex mapping operation of programmers with a simple area-matching operation. As there is no limit to clothing designs, the variousfashion design creations of designers and the diverse customizing demands of customers can be satisfied at low cost with high efficiency. This is not restricted to T-shirts or eco-bags but can be applied to all woven wear, including men's, women's, and children's clothing, except knitwear.

A Study on the Characteristic of Internal Changing of Departments after Establishment in General Hospital - Focused on the KS Hospital - (국내 종합병원의 건립후 나타난 부문별 내부변화 특성에 관한 연구 - KS 병원의 사례를 중심으로 -)

  • Cho, Jun-Young;Yang, Nae-Won
    • Korean Institute of Interior Design Journal
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    • v.17 no.2
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    • pp.75-82
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    • 2008
  • Weeks who is an architect in England suggest that let us consider the hospital architecture as not determined architecture but an undetermined architecture. Because it has been changing unexpectedly. The changing process of hospital architecture is required that it has to involve the new function and be a role model because of variations of environmental factors. For silving the requirements above mentioned, hospital architecture takes the way of appropriateness inner origin form and finally it considers new formation. The 53% of hospital buildings in Korea were built in 1980s. For 30years, these buildings have been not only extended a buildings but also changed in parts of functions and sizes on buildings which are original. The purpose of this study is producing the basic references which suggest solution to face on the changing of hospital building during planning it in the future using by analysis of variation inside the hospital building and grasping of characters in each departments. Each department is analyzed as follows. There is no inner change but only expansion partly by enlargement of building. In the outpatient, there is not only expansion by enlargement of building and but also extension toward other parts and the rate of variation of inside is high. In the diagnostic treatment, there are differences in diagnostic treatment. Surgical suit and diagnostic imaging have been expanded by enlargement than the change of inside. But the others of the departments have been changed by change of inside and also there are sometimes changes of inner walls.

Energy-efficient Multi-hop Communitation Strategy in Bluetooth Low Energy (Bluetooth Low Energy에서의 전송 효율적 멀티 홉 전송 전략)

  • Byun, Hyungho;Oh, Youngjune;Kim, Chong-kwon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.05a
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    • pp.77-80
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    • 2017
  • One of the fundamental limits of Bluetooth Low Energy(BLE) is that the data transmission is available via singlehop connection. In this research, we suggested the stable multihop transmission method to overcome this limitation. In multihop connection situation, multiple singlehop connection should be made and disconnected dynamically. Therefore, we stored the data within the GATT layer and tried to send it dynamically. We divided whole process as 4 states, and let each nodes transfers around each states to make data connection safely. Also, we set the transfer policy between each states during the transmission to make a robust system. From the experiment in real-time environment, we proved that our method showed high rate of packet delivery in a multihop network, which consists of more than 3 nodes.

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A simulation module to practice hydraulic mechanical governors and its adjustment characteristics for stability (유압기계식 거버너의 실습용 시뮬레이션 모듈과 안정도의 조정 특성)

  • Choi, Soon-Man
    • Journal of Advanced Marine Engineering and Technology
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    • v.37 no.5
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    • pp.533-540
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    • 2013
  • Prime movers in engine rooms inherently are much affected by the adjustment of their governors for the steady state and transient properties, consequently requiring that marine engineers shall be well familiar with the way to manage governor dials for normal operation. The hydro-mechanical governors basically have different control characteristics and adjustment parameters of stability from digital governors. The former include compensation mechanism using dash pot while the control algorithm of the latter is usually based on the PID action. This study is for configuring a simulation module to let trainees practice how to adjust dials for stability on hydraulic governors in the view that the practice by real governors and engines is time consuming and high cost for operation. The governor module includes the adjusting points such as speed set, speed droop, needle valve and compensation pointer with engine module of $2^{nd}$ order coupled. The results of simulation showed satisfactory responses as a training tool for the adjustment of control parameters.

A Characteristics of Directional Orientation of the Houses on Sangas, Imha, Hawoosan, Walgok Traditional Villages of Geomantic North (북향형국(北向形局)의 전통마을에서 주택의 방위적(方位的) 특성에 관한 연구 - 상사, 임하, 하우산, 월곡 마을을 중심으로 -)

  • Lee, Hyun-Byung;Kim, Sung-Woo
    • Journal of architectural history
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    • v.18 no.3
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    • pp.27-44
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    • 2009
  • In Korea, the direction of houses are typically determined by considering the directional orientation and shape of the mountain range rather than ignoring the geographical feature of the mountain range. Traditional villages of Korea are known to have very particular ways of adopting the geomantic surroundings of natural environment. This is very true especially have a high mountain in the back and a lower mountain in front. At the same time, most of the houses tend to prefer south as a man direction so that they can receive more sun light. However, if the mountain range faces north, it will not be easy to determine the directional orientation of houses. This paper, therefore, tries to identify how the houses of villages facing north, direst the orientation. This, the northern village, solves the problem by facing all direction rather than one major direction. The houses of the villages facing north, tend to revise the direction by changing the back mountain(주산) or front mountain(인산) that helps them change the direction towards he range of eastern or western direction. As a result, the houses tend to the direction towards east and wes compared to north and south. The directional orientation of houses was clearly distributed or concentrated by depending of the shape and directional orientation of the mountain range. This kind of research let us know the relationship between the natural north direction, the direction of geomantic surrounding, and the direction of houses in traditional Korean villages.

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The Experiences of Alternative Therapy with the Menopausal Symptom in middle-aged Women (중년여성의 갱년기 증상완화를 위한 대체요법 경험)

  • Lee, Hea-Sook
    • The Journal of Korean Academic Society of Nursing Education
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    • v.10 no.1
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    • pp.149-160
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    • 2004
  • The primary purpose of this study was to describe psychological aspects of menopausal women who have experiences on alternative therapies, such as pomegranate tree fluid, life pack, evening primerose, zacro syrup, zacro pill, multi-vitamin, oriental medicine instead of estrogen. In order to have insights on the participants behaviors, this qualitative research was conducted. The participants in this study were six women who have been taking at least one of the alternative therapies to relieve the menopausal symptom. Data had been collected from November 2002 to May 2003. The interview questions were about motivations to seek the alternative therapy, menopausal symptoms, feelings or positive effects after the treatment. The interviews were recorded and transcribed into written documents. The method described by Giorgi was utilized for data analysis. The study results were as follows : 1. The participants sought the alternative therapy based on their own information or by friends' recommendations. The motivations of taking the therapy were to live younger and healthier by reliving menopausal symptoms including somatic symptoms, such as irregular menstruation, flushing sense, cold sweating, insomnia, dull headache, vagina dryness, cystitis after sexual intercourse, joint pain, nervousness, depression, skin dryness, and suppression of activity. 2. The participants expressed that they became more active and felt better with disappearing menopausal symptoms after about 2 to 3 weeks treatment. 3. The participants did not want to accept the fact that they had menopause, which caused avoidance of having medical diagnosis and medical treatment. They also did not want to let their spouses know about their symptoms. 4. The major reason of taking the alternative therapy was to avoid the side effects of estrogen therapy in spite of high costs of the alternative way. 5. The participants suggested that menopausal women needed to be educated about physical and psychological symptoms of menopause. They also needed to be informed about how to manage it. In conclusion, accurate information about foods and drugs utilized for the alternative therapy was needed. Medically proved methods to recognize positive effects and side effects were also necessary. These goals could be achieved by continuous medical observations and further research.

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