• Title/Summary/Keyword: Field heat

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Development of a UAV-Based Urban Thermal Comfort Assessment Method (UAV 기반 도시 공간의 열 쾌적성 평가기법 개발)

  • Seounghyeon Kim;Bonggeun Song;Kyunghun Park
    • Journal of the Korean Association of Geographic Information Studies
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    • v.27 no.2
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    • pp.61-77
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    • 2024
  • The purpose of this study was to develop a method for rapidly diagnosing urban thermal comfort using Unmanned Aerial Vehicle (UAV) based data. The research was conducted at Changwon National University's College of Engineering site and Yongji Park, both located in Changwon, Gyeongsangnam-do. Baseline data were collected using field measurements and UAVs. Specifically, the study calculated field measurement-based thermal comfort indices PET and UTCI, and used UAVs to create and analyze vegetation index (NDVI), sky view factor (SVF), and land surface temperature (LST) images. The results showed that UAV-predicted PET and UTCI had high correlations of 0.662 and 0.721, respectively, within a 1% significance level. The explanatory power of the prediction model was 43.8% for PET and 52.6% for UTCI, with RMSE values of 6.32℃ for PET and 3.16℃ for UTCI, indicating that UTCI is more suitable for UAV-based thermal comfort evaluation. The developed method offers significant time-saving advantages over traditional approaches and can be utilized for real-time urban thermal comfort assessment and mitigation planning

The Reliability Evaluation about the Triode-Type CNT Emission Source (삼극형 CNT 전자원에 대한 신뢰성 평가)

  • Kang, J.T.;Kim, D.J.;Jeong, J.W.;Kim, D.I.;Kim, J.S.;Lee, H.R.;Song, Y.H.
    • Journal of the Korean Vacuum Society
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    • v.18 no.2
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    • pp.79-84
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    • 2009
  • The electron emission source of triode type has been fabricated using CNT paste. The nano Ag particle and photosensitive polymers were added to the CNT paste. The surface roughness of the CNT emitter was uniform by the back exposure method. The added nano Ag particle improves the adhesion and the electric conductance with small variation in the CNTs and between electrode. After the aging with heat-exhausting, the reliability of the triode CNT electron source was secured in the high voltage and current operation for 12 hours. At this time, the gate leakage current was about 10 % less than.

Integrated Numerical Analysis of Induction-Heating-Aided Injection Molding Under Interactive Temperature Boundary Conditions (열-유동 상호작용을 고려한 유도가열 적용 미세 사출성형의 통합적 수치해석)

  • Eom, Hye-Ju;Park, Keun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.34 no.5
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    • pp.575-582
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    • 2010
  • In recent years, several rapid-mold-heating techniques that can be used for the injection molding of thin-walled parts or micro/nano structures have been developed. High-frequency induction heating, which involves heating by electromagnetic induction, is an efficient method for the rapid heating of mold surfaces. The present study proposes an integrated numerical model of the high-frequency induction heating process and the resulting injection molding process. To take into account the effects of thermal boundary conditions in induction heating, we carry out a fully integrated numerical analysis that combines electromagnetic field calculation, heat transfer analysis, and injection molding simulation. The proposed integrated simulation is extended to the injection molding of a thin-wall part, and the simulation results are compared with the experimental findings. The validity of the proposed simulation is discussed according to the ways of the boundary condition imposition.

A Study about medical doctors of the school of Seowon (서원학파(西源學派) 의가(醫家)에 관(關)한 연구(硏究))

  • Yoon, Chang-Yeol
    • Journal of Korean Medical classics
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    • v.26 no.3
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    • pp.1-9
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    • 2013
  • Objective : In South Song era, Choe Ga-eon(崔嘉彦) built Seowonam(西源庵), lived as a hermit and communicated with Juja(朱子) in LuShan(廬山), JiangXi province(江西省), JiuJiang city(九江市). Maekgyeol(脈訣) written by him significantly influenced the forthcoming medical doctors, who took over his studies and were called the school of Seowon. Little information about his life and his successors encouraged this study. Method : The core contents of Maekgyeol(脈訣), his life based on Waryongamgi(臥龍庵記) and Seowongamgi(西源庵記) written by Juja(朱子) and his successors on the basis of various medical books were investigated. Result : The Seowonam(西源庵) is located at the entrance of xiufeng Scenic spot(秀峰景區) which is 6km west from center of Xingzi county(星子縣), JiangXi province(江西省), JiuJiang city(九江市). The points of Maekgyeol(脈訣) are inferring the symptom of wind, energy, cold and heat by categorizing seven exterior and eight interior pulse into four pulses of float, sink, slow and quick and diagnosing a disease of three warmer and the five viscera and the six entrails by subordinating four pulses to Chon, Gwan, and Cheok(寸關尺). By writing the book of Sawonron(四原論) he clarified the clinical point, pulse, disease, symptom, treatment with learning the cause of a disease through pulse, understanding the symptom through a disease, and giving a remedy through a symptom. Then he communicated with Juja(朱子) assigned to NanKangJun(南康軍) as a ruler. He helped Juja(朱子) to build Waryongam(臥龍庵) and Juja(朱子) wrote Seowonamgi(西源庵記) for him. Conclusion : The members of medical doctors of the school of Seowon were Choe Ga-eon(崔嘉彦) and his follower Yu Gae(劉開), Yugae's disciple Eom Yong-hwa(嚴用和) and Ju Jong-yang(朱宗陽) and Ju Jong-yang's disciple Jang Do-jung(張道中). They, who were famous for pulse, had contributed to advancing study of pulses in the field of oriental medicine.

Compressive Strength Generation Properties of Concrete using a Large Amount of Industrial Byproduct (산업부산물을 다량 사용한 콘크리트의 압축강도 발현 특성 검토)

  • Kim, Yong-Ro;Song, Young-Chan;Park, Jong-Ho;Jeong, Yong
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.6 no.2
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    • pp.67-73
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    • 2011
  • In this study, it was investigated compressive strength generation of concrete using high volume mineral admixture obtaining fundamental data for the application of concrete structure in construction field. For this, it was evaluated compressive strength with unit binder contents($310{\sim}410kg/m^3$), replacement ratio of mineral admixture(70~90%), unit water contents($140{\sim}150kg/m^3$) and curing temperature in the normal strength range. Also, after producing mock-up structure, hydration heat and compressive strength generation was evaluated to examine properties in the concrete member. In case of concrete using a large amount of industrial byproducts which was reviewed in this study, it is possible to secure compressive strength more than 24MPa at age 28days with about $13^{\circ}C$ ambient temperature of curing condition and that is considered to be applied to structure at construction site.

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Functional Drainage Evaluation of Block Paving through the Usage of Sludge and Wheel Tracking Test (슬러지 투입 및 휠트랙킹 시험을 이용한 블록 포장의 기능적 투수평가)

  • Lee, Sang-Yum;Jung, Hoon-Hee;Mun, Sung-Ho;Park, Dae-Geun;Park, Kyong-Min
    • International Journal of Highway Engineering
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    • v.13 no.3
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    • pp.31-38
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    • 2011
  • As the percentage of permeable ground is reduced due to the increased impermeable roads of major cities, a heat island phenomenon can be dominantly observed, resulting in increased temperature. In addition, rainfall that would have been naturally absorbed and retained by the permeable ground is overflowed due to large volumes of run-off water, resulting in more sewer failures and increased erosion. In terms of permeable pavement system, block paving has been used anywhere as well as provides many years of service. The permeable block paving is an effective alternative to the more traditional asphalt or plain concrete for minor roads; furthermore, it looks a lot better than other pavements. In this study, the functional drainage evaluation of block paving was carried out, considering the usage of experimental sludge and wheel tracking test, in order to simulate the field condition of roads.

A Study on the Historical Changes in the Theory of 'Syndrome Differentiation' from the Viewpoint of Yoon Gilyeong (윤길영(尹吉榮)의 변증론(辨證論) 변천(變遷) 연구(硏究)에 대한 고찰)

  • Kim, Gyeong Cheol;Lee, Hai Woong
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.19 no.3
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    • pp.151-158
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    • 2015
  • Objectives Syndrome differentiation and treatment (辨證論治) is one of the core theories in Korean medicine and syndrome differentiation (辨證) constitutes a branch of disease diagnosis in Korean medicine. Yoon Gil-Young, one of the modern outstanding scholar of basic medical science in Korean medicine, wrote on basic theories of Korean medicine such as physiology, pathology, formula science, etc. Hereby we will analyze and discuss his works to understand his recognition of historical changes in the syndrome differentiation. Methods We conducted researches into the two works of Yoon Gil-Young's, which are "The Clinical Formula Science of Eastern Medicine (東醫臨床方劑學)" and "The theory of Four-Constitution Medicine (四象體質醫學論)". From Yoon's academic standpoint which connects the basic medical science with the clinical medicine, we analyzed his opinion about syndrome differentiation and its historical changes. Results According to Yoon's research work on syndrome differentiation and its historical changes, the development of syndrome differentiation, which goes in harmony with the history of Korean medicine, has its deep root in " Huangdi's Internal Classic (黃帝內經)" and "Treatise on Cold Damage and Miscellaneous Diseases (傷寒雜病論)". And through "Treatise on the Spleen and Stomach (脾胃論)" and the articles of warm disease (溫病論), the theory of syndrome differentiation became extended to the whole clinical diagnostic field in Korean medicine, finally including the achievements in "Treasured Mirror of Eastern Medicine (東醫寶鑑)", "Longevity and Life Preservation in Eastern Medicine (東醫壽世保元)". Conclusions Yoon Gil-Young recognized that the system of syndrome differentiation was developed in accordance with the theories from the "Treatise on Cold Damage and Miscellaneous Diseases", then the "Treatise on the Spleen and Stomach" and the articles of warm disease. The four-constitution medicine in Korea and Koho school in Japan which lays emphasis on abdominal signs also contributed to its development. Syndrome differentiation can be categorized basically into three states of intrinsic cold (本寒), intrinsic deficiency (本虛), intrinsic heat (本熱) according to the deficiency and excess in human body metabolism.

Utilization of CFD Simulation Model for a Bubble Column Photobioreactor (버블 칼럼 광생물반응기의 내부 유동분석을 위한 전산유체역학 시뮬레이션 모델의 이용)

  • Yoo, J.I.;Lee, I.B.;Hwang, H.S.;Hong, S.W.;Seo, I.H.;Bitog, J.P.;Kwon, K.S.;Kim, Y.H.
    • Journal of The Korean Society of Agricultural Engineers
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    • v.51 no.5
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    • pp.1-8
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    • 2009
  • Photobioreactor (PBR) that houses and cultivates microalgae providing a suitable environment for its growth, such as light, nutrients, CO2, heat, etc. is now getting more popular in the last decade. Among the many types of PBRs, the bubble column type is very attractive because of its simple construction and easy operation. However, despite the availability of these PBRs, only a few of them can be practically used for mass production. Many limitations still holdback their use especially during their scale-up. To enlarge the culture volume and productivity while supplying optimum environmental conditions, various PBR structures and process control are needed to be investigated. In this study, computational fluid dynamics (CFD) was economically used to design a bubble-column type PBR taking the place of field experiments. CFD is a promising technique which can simulate the growth and production of microalgae in the PBR. To study bubble column PBR with CFD, the most important factor is the possibility of realizing bubble. In this study, multi-phase models which are generally used to realize bubbles were compared by theoretical approaches and comparing in a 2D simulation. As a result, the VOF (volume of fluid) model was found to be the most effective model to realize the bubbles shape as well as the flow inside PBR which may be induced by bubble injection. Considering the accuracy and economical efficiency, 0.005 second time step size was chosen for 2.5 mm mesh size. These results will be used as criteria for scale-up in the PBR simulation.

Coupled Nonlinear Finite Element-Boundary Element Analysis of Nuclear Waste Storage Structures Considering Infinite Boundaries (비선형 유한요소-경계요소 조합에 의한 핵폐기구조체의 무한영역해석)

  • 김문겸;허택녕
    • Computational Structural Engineering
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    • v.6 no.4
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    • pp.89-98
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    • 1993
  • As the construction of nuclear power plants are increased, nuclear wastes disposal has been faced as a serious problem. If nuclear wastes are to be buried in the underground stratum, thermo-mechanical behavior of stratum must be analyzed, because high temperature distribution has a significant effect on tunnel and surrounding stratum. In this study, in order to analyze the structural behavior of the underground which is subject to concentrated heat sources, a coupling method of nonlinear finite elements and linear boundary elements is proposed. The nonlinear finite elements (NFE) are applied in the vicinity of nuclear depository where thermo-mechanical stress is concentrated. The boundary elements are also used in infinite domain where linear behavior is expected. Using the similar method as for the problem in mechanical field, the coupled nonlinear finite element-boundary element (NFEBE) is developed. It is found that NFEBE method is more efficient than NFE which considers nonlinearity in the whole domain for the nuclear wastes depository that is expected to exhibit local nonlinearity behavior. The effect of coefficients of the rock mass such as Poisson's ratio, elastic modulus, thermal diffusivity and thermal expansion coefficient is investigated through the developed method. As a result, it is revealed that the displacements around tunnel are largely dependent on the thermal expansion coefficients.

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Effect of Carthami Tinctorii Fructus Herbal-acupuncture Solution(CTF-HAS) on Gene Expression in HepG2 carcinomar cells by Proteomic Analysis (Proteomic Analysis기법을 이용한 홍화자약침액(紅花子藥鍼液)이 간암세포주(肝巖細胞柱)의 유전자(遺傳子) 발현(發顯)에 미치는 영향(影響))

  • Lee, Kyung-Min;Lim, Seong-Chul;Jeong, Tae-Young;Seo, Jung-Chul;Han, Sang-Won
    • Journal of Pharmacopuncture
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    • v.8 no.2
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    • pp.23-28
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    • 2005
  • Objective : It has long been known about the osteogenic effect of CTF-HAS on bone tissues. However, it has not been determined the effect of CTF-HAS on cancer cells. The purpose of this study is to screen the CTF-HAS mediated differentially expressed genes in cancer cells such as HepG2 hepatoma cells lines. Methods : CTF-HAS was prepared by boiling and stored at $-70^{\circ}C$ until use. For proteomic analysis, total protein was analyzed by 2D gel electrophoresis and Q-TOF mass spectrometer. Results : In proteomic analysis, three spots were identified by 2D-gel electrophoresis and Q-TOF analysis. One down-regulated protein was heat shock 70kDa protein 5 and up-regulated proteins were chaperonin and 2-phospho -pyruvate-hydratase ${\alpha}-enolase$ by 1.5mg/ml of CTF-HAS. Discussion : Proteomic analysis approach were performed to screen the differential expression genes. The screened genes will be used for the better understanding in therapeutic effect of CTF-HAS on cancer field.