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설비공학 분야의 최근 연구 동향: 2011년 학회지 논문에 대한 종합적 고찰 (Recent Progress in Air-Conditioning and Refrigeration Research: A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2011)

  • 한화택;이대영;김서영;최종민;백용규;김수민
    • 설비공학논문집
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    • 제24권6호
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    • pp.521-537
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    • 2012
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2011. 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) Research trends of thermal and fluid engineering have been surveyed as groups of fluid machinery and fluid flow, thermodynamic cycle, and new and renewable energy. Various topics were presented in the field of fluid machinery and fluid flow. Research issues mainly focused on the rankine cycle in the field of thermodynamic cycle. In the new and renewable energy area, researches were presented on geothermal energy, fuel cell, biogas, reformer, solar water heating system, and metane hydration. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer, nanofluids and industrial heat exchangers. Researches on heat transfer characteristics included heat transfer above liquid helium surface in a cryostat, methane hydrate formation, heat and mass transfer in a liquid desiccant dehumidifier, thermoelectric air-cooling system, heat transfer in multiple slot impinging jet, and heat transfer enhancement by protrusion-in-dimples. In the area of pool boiling and condensing heat transfer, researches on pool boiling of water in low-fin and turbo-B surfaces, pool boiling of R245a, convective boiling two-phase flow in trapezoidal microchannels, condensing of FC-72 on pin-finned surfaces, and natural circulation vertical evaporator were actively performed. In the area of nanofluids, thermal characteristics of heat pipes using water-based MWCNT nanofluids and the thermal conductivity and viscosity were measured. In the area of industrial heat exchangers, researches on fin-tube heat exchangers for waste gas heat recovery and Chevron type plate heat exchanger were implemented. (3) Refrigeration systems with alternative refrigerants such as $CO_2$, hydrocarbons, and mixed refrigerants were studied. Heating performance improvement of heat pump systems were tried applying supplementary components such as a refrigerant heater or a solar collector. The effects of frost growth were studied on the operation characteristic of refrigeration systems and the energy performance of various defrost methods were evaluated. The current situation of the domestic cold storage facilities was analyzed and the future demand was predicted. (4) In building mechanical system fields, a variety of studies were conducted to achieve effective consumption of heat and maximize efficiency of heat in buildings. Various researches were performed to maximize performance of mechanical devices and optimize the operation of HVAC systems. (5) In the fields of architectural environment and energy, diverse purposes of studies were conducted such as indoor environment, building energy, and renewable energy. In particular, renewable energy and building energy-related researches have mainly been studied as reflecting the global interests. In addition, various researches have been performed for reducing cooling load in a building using spot exhaust air, natural ventilation and energy efficiency systems.

대량 수혈을 받은 환아들에서 정맥 투여한 deferoxamine의 효과 (Effect of intravenous deferoxamine in multiply transfused patients)

  • 오상민;강준원;김선영
    • Clinical and Experimental Pediatrics
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    • 제50권12호
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    • pp.1225-1230
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    • 2007
  • 목 적 : 만성 빈혈로 대량 수혈을 받아야 하는 환아들에서는 조직과 장기에 철이 축적될 수 있다. 이러한 환아들에서 효과적인 철킬레이트 치료의 목적은 충분한 양의 철을 제거하여 체내에서 철로 인한 장기 손상이 나타나지 않도록 하는데 있다. 본 연구는 후향적으로 대량 수혈을 받은 환아들에서 정맥 투여한 deferoxamine의 효과를 알아보고자 하였다. 방 법 : 2005년 3월부터 2007년 1월까지 15명의 대량 수혈을 받았던 환아들을 대상으로 하였으며 이들 중 수혈 의존성 환아들은 한 달에 1단위 이상의 농축 적혈구 수혈을 최근 6개월 이상 계속 받고 있는 환아들로 정의하였다. 7일 동안 deferoxamine을 10-30 mg/kg/day로 24시간 지속 정맥주입하였으며 투여 전, 후 그리고 3개월 후의 혈청 철, 총철결합능, ferritin을 수혈 의존성 환아들과 수혈 비의존성 환아들로 나누어 비교하였다. 결 과 : 6명의 남아와 9명의 여아가 있었으며 이들의 나이는 5.6-21.3(중앙값 8.3)세였고 수혈 의존성 환아들은 7명, 수혈 비의존성 환아들은 8명이었다. 수혈 의존성 환아들의 ferritin은 deferoxamine 투여 전과 후, 3개월 후에 의미 있는 차이를 보이지 않았으나 수혈 비의존성 환아들에서는 투여 전과 비교 시 투여 3개월 후에는 의미 있는 감소를 보였다(P=0.046). Deferoxamine 정맥주입과 연관된 이상 반응은 경미하였으며 1-2일 내에 소실되었다. 결 론 : 7일 동안 정맥주입하는 deferoxamine은 수혈 비의존성 환아들에서 단기간의 효과적인 치료로 사용될 수 있을 것으로 생각되지만 수혈 의존성 환아들의 경우에는 철의 축적을 막기 위해 유지 요법이 필요할 것으로 생각된다.

백서 하악골의 기능적 전방위가 악관절 원판에 미치는 영향 (CHANGES IN THE SHAPE AND ULTRASTRUCTURE OF THE ARTICULAR DISK OF RAT FOLLOWING POSTURAL HYPERPROPULSOR)

  • 장병천;경희문;성재현;배용철
    • 대한치과교정학회지
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    • 제24권4호
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    • pp.917-932
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    • 1994
  • 백서에 있어서 기능적 전방위 장치가 악관절 원판에 미치는 변화 양상을 관찰하기 위하여 생후 4주령 부터 3주간 및 4주간 기능적 전방위 장치를 장착한 후 백서의 악관절 부위를 적출하여 광학 및 전자 현미경으로 관찰한 결과 다음의 소견을 얻었다. 실험 2주군에 있어서 악관절 원판의 전방부 및 후방부 두께는 실험군이 대조군보다 통계적으로 유의성 있는 증가를 나타내었다. 실험 4주군에 있어서 악관절 원판의 두께는 전방부에서 실험군이 대조군보다 통계적으로 유의성 있는 증가를 나타내었다. 광학 현미경 소견에서 2주 및 4주실험군의 전방부에서 대조군에 비하여 섬유아세포의 밀도가 높은 경향을 나타내었다. 전자현미경 소견 2주군에서 내강이 확장된 RER이 대단히 잘 발달하여 collagen등 세포외 물질의 합성이 왕성한 것으로 추측되는 세포, 내강이 확장되지는 않았으나 RER이 발달하고 free ribosome이 발달되어 세포내 세사의 합성이 활발한 것으로 추측되는 세포, 전형적 인 chondroid cell이 관찰되었으며, 실험군 전방부에서는 대조군에 비하여 내강이 확장된 RER이 발달된 섬유 모세포들의 비율이 높았다. 4주 실험군에서 전방부는 대조군에 비하여 전반적으로 세포밀도가 높았으며 RER 및 free ribosome이 발달된 섬유 모세포 비율이 높았다. 이상의 결과를 종합하면, 하악골의 기능적 위치 변화는 관절원판의 부위에 따라 기계적 부하를 변화시키며, 결과적으로 세포수준에서 이에 적응 혹 대응하므로써 형태의 변화가 일어날 수 있다고 사료된다.

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설비공학 분야의 최근 연구 동향 : 2007년 학회지 논문에 대한 종합적 고찰 (Recent Progress in Air Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2007)

  • 한화택;신동신;최창호;이대영;김서영;권용일
    • 설비공학논문집
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    • 제20권12호
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    • pp.844-861
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    • 2008
  • The papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during the year of 2007 have been reviewed. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environments. The conclusions are as follows. (1) The research trends of fluid engineering have been surveyed as groups of general fluid flow, fluid machinery and piping, etc. New research topics include micro nano fluid, micropump and fuel cell. Traditional CFD was still popular and widely used in research and development. Studies about fans and pumps were performed in the field of fluid machinery. Characteristics of flow and fin shape optimization are studied in the field of piping system. (2) The research works on heat transfer have been reviewed in the field of heat transfer characteristics, heat exchangers, and desiccant cooling systems. The research on heat transfer characteristics includes thermal transport in pulse tubes, high temperature superconductors, ground heat exchangers, fuel cell stacks and ice slurry systems. For the heat 'exchangers, the research on pin-tube heat exchanger, plate heat exchanger, condensers and gas coolers has been cordially implemented. The research works on heat transfer augmenting tubes have been also reported. For the desiccant cooling systems, the studies on the design and operating conditions for desiccant rotors as well as performance index are noticeable. (3) In the field of refrigeration, many papers were presented on the air conditioning system using CO2 as a refrigerant. The issues on the two-stage compression, the oil selection, and the appropriate oil charge were treated. The subjects of alternative refrigerants were also studied steadily. Hydrocarbons, DME and their mixtures were considered and various heat transfer correlations were proposed. (4) Research papers have been reviewed in the field of building facilities by grouping into the researches on heat and cold sources, air conditioning and air cleaning, ventilation and fire research including tunnel ventilation, flow control of piping system, and sound research with drain system. Main focuses have been addressed to the promotion of efficient or effective use of energy, which helps to save energy and results in reduced environmental pollution and operating cost. (5) Studies were mostly focused on analyzing the indoor environment in various spaces like cars, old tombs, machine rooms, and etc. in an architectural environmental field. Moreover, subjects of various fields such as the evaluation of noise, thermal environment, indoor air quality and development of energy analysis program were researched by various methods of survey, simulation, and field experiment.

비육후기 사료에서 비타민-미량광물질 첨가제의 제거가 돼지의 성장 능력, 근육 내 비타민 E 및 분 중 미량광물질 함량에 미치는 영향 (Effects of Deletion of Supplementary Vitamins and Trace Minerals on Performance, Muscle Vitamin E and Fecal Trace Mineral Contents in Finishing Pigs)

  • 이승철;이종언;김규일
    • Journal of Animal Science and Technology
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    • 제45권4호
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    • pp.543-550
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    • 2003
  • 비육후기 사료에서 비타민-미량광물질 첨가제의 제거가 돼지의 성장, 사료효율, 혈 중 헤모글로빈 농도, 돈육 내 비타민 E 및 분 중 미량광물질 함량에 미치는 영향을 구명하기 위하여 사육환경이 서로 다른 돈사에서 두 번의 시험이 수행되었다. 시험 1에서는 45두의 비육돈 (평균체중 70 kg, 3원교잡종)을 돈방 당 5두씩 배치하고, 대조구 (비타민-미량광물질 프리믹스 첨가), 프리믹스 50% 및 0% 첨가구에 각각 3돈방을 배치하여 환기와 온도가 제어되지 않는 재래식 톱밥돈사에서 7주동안 사양한 후 도축하였다. 시험 2에서는 돈사 환기 및 온도가 자동 조절되는 슬러리 무창돈사에서 36두의 요크셔 비육돈 (평균체중 56 kg)을 돈방 당 4두씩 배치, 대조구(비타민-미량광물질 프리믹스 첨가), 프리믹스 0% 및 프리믹스 0%+비타민 E(100 mg $\alpha$-tocopherol acetate/kg) 첨가구에 각각 3돈방을 배치하여 7주 동안 사양 후 도축하였다. 두 시험에서 처리 간 일당증체량, 사료섭취량, 사료효율 및 도체특성은 유의차가 없었으나 시험 2에서는 대조구의 일당증체량이 약간 높은 경향을 보였다. 프리믹스의 미 첨가는 헤모글로빈 함량이나 적혈구 수에 영향을 주지 않았다. 분 중 Mn과 Zn 함량은 대조구에서 프리믹스를 첨가하지 않은 다른 처리에서 보다 매우 높게 (P<0.01) 나타났다. 혈 중 미량광물질 함량은 처리간 유의차를 보이지 않았다. 햄 근육 (gluteus maxima) 내 $\alpha$-tocopherol 함량은 프리믹스를 첨가하지 않음으로써 감소하였으나 (P〈 0.01), 도살 전 2주 동안 $\alpha$-tocopheryl acetate(100mg/kg diet)를 급여함으로써 프리믹스 첨가구보다도 더 증가하였다 (P< 0.01). 본 연구결과 돼지 비육후기 사료에 비타민-미량광물질 프리믹스의 첨가는 성장율에는 큰 영향을 미치지 않으면서 분 중 일부 미량광물질을 증가시키기 때문에 경제적인 손실과 토양오염의 위험이 있음을 말해 준다. 프리믹스 제거로 인한 고기 내 비티민 E 함량의 감소는 마지막 2주동안 $\alpha$-tocopherol 를 첨가 급여함으로써 회복될 수 있다.

우치에 대한 All-in-one 상아질 결합제의 전단결합강도 비교 연구 (STUDY ON THE SHEAR BOND STRENGTH OF ALL-IN-ONE DENTIN BONDING SYSTEM)

  • 박형주;유승훈;김종수
    • 대한소아치과학회지
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    • 제33권4호
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    • pp.661-672
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    • 2006
  • 우치 60개를 준비하여 법랑질과 상아질에 대하여 각각 1군 AQ Bond, 2군 AQ Bond $Plus^{TM}$, 3군 Single $Bond^{TM}$로 설정하고, 군당 10개씩 배정하였고, 군당 혼화층 관찰에 5개와 resin tag 관찰을 위해 5개씩 배정하였다. 준비된 우치의 법랑질과 상아질을 노출시킨 후 제조사의 지시에 따라 표면을 처리하고, 내경 3mm의 폴리에틸렌 튜브를 이용하여 $Z-250^{TM}$ 복합레진 접착을 시행하였다. 100% 습윤 상태에서 24시간동안 보관 후 $5^{\circ}C$$55^{\circ}C$ 조건하에서 500회 열순환을 시행하였다. 만능시험기를 분당 cross head speed 5mm 속도로 설정하고 100kg F load cell을 사용하여 전단결합강도를 측정하고 파절된 시편들을 수거하여 주사전자현미경으로 파절면을 관찰하였다. 혼화층과 resin tag 관찰을 위하여 상아질 접착면에 대해 수직으로 절단하고 인산과 질산으로 처리한 후 주사전자현미경으로 관찰하였다. 이상의 결과를 토대로 행동 조절에 어려움이 많은 소아 환자의 복합레진 수복시 적용 과정 및 시간 단축이 장점으로 부각되고 있는 all-in-one system의 임상 적용 가능성을 평가하고 다음과 같은 결론을 얻었다. 1. 전단 결합 강도 측정결과 1군, 2군 간에는 유의차가 없었으나, 3군이 1군과 2군에 비해 높은 전단 결합 강도를 보였으며 통계학적 유의차를 보였다 (p<0.05). 2. 파절 양상 관찰 결과 1군과 2군의 법랑질과 상아질 모두에서 그리고 3군의 상아질에서 주로 adhesive fracture 양상을 보였으며, 3군 법랑질에서 각각 cohesive와 adhesive fracture가 균등한 분포를 보였다. 3. 주사 전자 현미경 소견에서 1군과 2군은 resin tag형성이 매우 미약하고 불규칙한 양상을 보인 반면, 3군에서는 비교적 긴밀하게 형성된 resin tag이 관찰되었으며 resin tag의 표면에 형성된 뚜렷한 측부 가지들도 발견되었다.

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접착제 도포후 오염된 표면의 처리방법에 따른 복합레진의 전단결합강도와 미세누출 (SHEAR BOND STRENGTH AND MICROLEAKAGE OF COMPOSITE RESIN ACCORDING TO TREATMENT METHODS OF CONTAMINATED SURFACE AFTER APPLYING A BONDING AGENT)

  • 박주식;이석종;문주훈;조영곤
    • Restorative Dentistry and Endodontics
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    • 제24권4호
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    • pp.647-656
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    • 1999
  • The purpose of this study was to investigate the shear bond strength and marginal microleakage of composite to enamel and dentin according to different treatment methods when the applied bonding agent was contaminated by artificial saliva. For the shear bond strength test, the buccal and occlusal surfaces of one hundred twenty molar teeth were ground to expose enamel(n=60) and dentin surfaces(n=60). The specimens were randomly assigned into control and 5 experimental groups with 10 samples in each group. In control group, a bonding system(Scotchbond$^{TM}$ Multi-Purpose plus) and a composite resin(Z-100$^{TM}$) was bonded on the specimens according to manufacture's directions. Experimental groups were subdivided into 5 groups. After polymerization of an adhesive, they were contaminated with at artificial saliva on enamel and dentin surfaces: Experimental group 1 ; artificial saliva was dried with compressed air. Experimental group 2 ; artificial saliva was rinsed with air-water spray and dried. Experimental group 3 ; artificial saliva was rinsed, dried and applied an adhesive. Experimental group 4 ; artificial saliva was rinsed, dried, and then etched using phosphoric acid followed by an adhesive. Experimental group 5, artificial saliva was rinsed, dried, and then etched with phosphoric acid followed by consecutive application of both a primer and an adhesive. Composite resin(Z-100$^{TM}$) was bonded on saliva-treated enamel and dentin surfaces. The shear bond strengths were measured by universal testing machine(AGS-1000 4D, Shimaduzu Co. Japan) with a crosshead speed of 5mm/minute under 50kg load cell. Failure modes of fracture sites were examined under stereomicroscope. The data were analyzed by one-way ANOVA and Tukey's test. For the marginal microleakage test, Class V cavities were prepared on the buccal surfaces of sixty molars. The specimens were divided into control and experimental groups. Cavities in experimental group were contaminated with artificial saliva and those surfaces in each experimental groups received the same treatments as for the shear test. Cavities were filled with Z-100. Specimens were immersed in 0.5% basic fuchsin dye for 24 hours and embedded in transparent acrylic resin and sectioned buccolingually with diamond wheel saw. Four sections were obtained from the one specimen. Marginal microleakages of enamel and dentin were scored under streomicroscope and averaged from four sections. The data were analyzed by Kruskal-Wallis test and Fisher's LSD. The results of this study were as follows. 1. The shear bond strength to enamel showed lower value in experimental group 1(13.20${\pm}$2.94MPa) and experimental group 2(13.20${\pm}$2.94MPa) than in control(20.03${\pm}$4.47MPa), experimental group 4(20.96${\pm}$4.25MPa) and experimental group 5(21.25${\pm}$4.48MPa) (p<0.05). 2. The shear bond strength to dentin showed lower value in experimental group 1(9.35${\pm}$4.11MPa) and experimental group 2(9.83${\pm}$4.11MPa) than in control group(17.86${\pm}$4.03MPa), experimental group 4(15.04${\pm}$3.22MPa) and experimental group 5(14.33${\pm}$3.00MPa) (p<0.05). 3. Both on enamel and dentin surfaces, experimental group 1 and 2 showed many adhesive failures, but control and experimental group 3, 4 and 5 showed mixed and cohesive failures. 4. Enamel marginal microleakage was the highest in experimental group 1 and there was a significant difference in comparison with other groups (p<0.05). 5. Dentin marginal microleakages of experimental group 1 and 2 were higher than those of other groups (p<0.05). This result suggests that treatment methods, re-etching with 35% phosphoric acid followed by re-application of adhesive or repeating all adhesive procedures, will produce good effect on both shear bond strength and microleakage of composite to enamel and dentin if the polymerized bonding agent was contaminated by saliva.

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설비공학 분야의 최근 연구 동향: 2008년 학회지 논문에 대한 종합적 고찰 (Recent Progress in Air-Conditioning and Refrigeration Research: A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2008)

  • 한화택;최창호;이대영;김서영;권용일;최종민
    • 설비공학논문집
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    • 제21권12호
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    • pp.715-732
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    • 2009
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2008. 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) Research trends in thermal and fluid engineering have been surveyed in the categories of general fluid flow, fluid machinery and piping, new and renewable energy, and fire. Well-developed CFD technologies were widely applied in developing facilities and their systems. New research topics include fire, fuel cell, and solar energy. Research was mainly focused on flow distribution and optimization in the fields of fluid machinery and piping. Topics related to the development of fans and compressors had been popular, but were no longer investigated widely. Research papers on micro heat exchangers using nanofluids and micro pumps were also not presented during this period. There were some studies on thermal reliability and performance in the fields of new and renewable energy. Numerical simulations of smoke ventilation and the spread of fire were the main topics in the field of fire. (2) Research works on heat transfer presented in 2008 have been reviewed in the categories of heat transfer characteristics, industrial heat exchangers, and ground heat exchangers. Research on heat transfer characteristics included thermal transport in cryogenic vessels, dish solar collectors, radiative thermal reflectors, variable conductance heat pipes, and flow condensation and evaporation of refrigerants. In the area of industrial heat exchangers, examined are research on micro-channel plate heat exchangers, liquid cooled cold plates, fin-tube heat exchangers, and frost behavior of heat exchanger fins. Measurements on ground thermal conductivity and on the thermal diffusion characteristics of ground heat exchangers were reported. (3) In the field of refrigeration, many studies were presented on simultaneous heating and cooling heat pump systems. Switching between various operation modes and optimizing the refrigerant charge were considered in this research. Studies of heat pump systems using unutilized energy sources such as sewage water and river water were reported. Evaporative cooling was studied both theoretically and experimentally as a potential alternative to the conventional methods. (4) Research papers on building facilities have been reviewed and divided into studies on heat and cold sources, air conditioning and air cleaning, ventilation, automatic control of heat sources with piping systems, and sound reduction in hydraulic turbine dynamo rooms. In particular, considered were efficient and effective uses of energy resulting in reduced environmental pollution and operating costs. (5) In the field of building environments, many studies focused on health and comfort. Ventilation. system performance was considered to be important in improving indoor air conditions. Due to high oil prices, various tests were planned to examine building energy consumption and to cut life cycle costs.

설비공학 분야의 최근 연구 동향 : 2013년 학회지 논문에 대한 종합적 고찰 (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)

  • 이대영;김사량;김현정;김동선;박준석;임병찬
    • 설비공학논문집
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    • 제26권12호
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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.

설비공학 분야의 최근 연구 동향: 2014년 학회지 논문에 대한 종합적 고찰 (Recent Progress in Air-Conditioning and Refrigeration Research: A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2014)

  • 이대영;김사량;김현정;김동선;박준석;임병찬
    • 설비공학논문집
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    • 제27권7호
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    • pp.380-394
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    • 2015
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2014. 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 heat and mass transfer, cooling and heating, and air-conditioning, the flow inside building rooms, and smoke control on fire. Research issues dealing with duct and pipe were reduced, but flows inside building rooms, and smoke controls were 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 thermal contact resistance measurement of metal interface, a fan coil with an oval-type heat exchanger, fouling characteristics of plate heat exchangers, effect of rib pitch in a two wall divergent channel, semi-empirical analysis in vertical mesoscale tubes, an integrated drying machine, microscale surface wrinkles, brazed plate heat exchangers, numerical analysis in printed circuit heat exchanger. In the area of pool boiling and condensing, non-uniform air flow, PCM applied thermal storage wall system, a new wavy cylindrical shape capsule, and HFC32/HFC152a mixtures on enhanced tubes, were actively studied. In the area of industrial heat exchangers, researches on solar water storage tank, effective design on the inserting part of refrigerator door gasket, impact of different boundary conditions in generating g-function, various construction of SCW type ground heat exchanger and a heat pump for closed cooling water heat recovery were performed. (3) In the field of refrigeration, various studies were carried out in the categories of refrigeration cycle, alternative refrigeration and modelling and controls including energy recoveries from industrial boilers and vehicles, improvement of dehumidification systems, novel defrost systems, fault diagnosis and optimum controls for heat pump systems. It is particularly notable that a substantial number of studies were dedicated for the development of air-conditioning and power recovery systems for electric vehicles in this year. (4) In building mechanical system research fields, seventeen studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, and renewable energies, piping in the buildings. Proposed designs, performance 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 was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the evaluation of work noise in tunnel construction and the simulation and development of a light-shelf system. The subjects of building energy were worked on the energy saving of office building applied with window blind and phase change material(PCM), a method of existing building energy simulation using energy audit data, the estimation of thermal consumption unit of apartment building and its case studies, dynamic window performance, a writing method of energy consumption report and energy estimation of apartment building using district heating system. The remained studies were related to the improvement of architectural engineering education system for plant engineering industry, estimating cooling and heating degree days for variable base temperature, a prediction method of underground temperature, the comfort control algorithm of car air conditioner, the smoke control performance evaluation of high-rise building, evaluation of thermal energy systems of bio safety laboratory and a development of measuring device of solar heat gain coefficient of fenestration system.