다양한 기후조건에서의 진공 멤브레인 제습 시스템 성능 해석

임현정(Hyunjeong Lim),이진욱(Jinwook Lee),최상미(Sangmi Choi),임지훈(Jihun Lim),김민성(Minsung Kim) 대한기계학회 2019 대한기계학회 춘추학술대회 Vol.2019 No.11

As standard of living and average temperature in the summer season are increased, cooling load is rapidly increasing globally. It becomes important to develop innovative technologies that can replace the conventional vapor compression cycle because the cycle cannot be improved its efficiency anymore due to limit of technology. Vacuum membrane dehumidification system(VMD) is used for dehumidification in a membrane heat pump which is one alternative of the vapor compression cycle. In this paper, characteristics of vacuum membrane dehumidification systems are introduced and dehumidification COP of each typical VMD systems are simulated thermodynamically in various climate condition. Between two VMD systems, water vapor discharged VMD system showed the best dehumidification performance, but it sometimes has lower COP than condenser combined VMD system. Results are compared and discussed in depth.

다양한 진공 멤브레인 제습구조를 적용한 에어컨디셔너의 성능 비교

임현정(Hyunjeong Lim),최상미(Sangmi Choi),정민규(Min Gyu Jung),김민성(Minsung Kim) 대한설비공학회 2018 대한설비공학회 학술발표대회논문집 Vol.2018 No.6

An alternative technology that surpasses the efficiency of conventional vapor compression cycle is needed to meet the increased demand for air conditioning. As one of the candidates, we analyzed a membrane heat pump. The membrane heat pump is designed to maximize the cycle efficiency by applying hydrophobic water-passing dense membrane in heat exchangers, which can decrease energy consumption in dehumidification and vapor compression process. This new heat pump separates air-conditioning process into dehumidification and latent heat cooling. There are three types of vacuum membrane dehumidification structure which can separate steam from the air. In this study, the heat and mass transfer of membrane heat pump in each process are modeled and COPs of each system are compared.

이온투과성 멤브레인을 이용한 개방형 증기압축식 에어컨디셔너의 성능해석

임현정(Hyunjeong Lim),김찬중(Chanjoong Kim),조연주(Yeon Joo Cho),최상미(Sangmi Choi),김민성(Minsung Kim) 대한설비공학회 2017 대한설비공학회 학술발표대회논문집 Vol.2017 No.6

An alternative technology that surpasses the efficiency of conventional vapor compression cycle is needed to meet the increased demand for air conditioning. As one of the candidates, we analyzed a membrane heat pump. The membrane heat pump is designed to maximize the cycle efficiency by applying hydrophobic water-passing dense membrane in heat exchangers, which can decrease energy consumption in dehumidification and vapor compression process. This new heat pump separates air-conditioning process into dehumidification and latent heat cooling. Air is dehumidified through steam separation membrane and cooled by water cooling loop. For cooling water cycle, vacuum pump and circulation pump are equipped to establish semi-open water cycle. From the simulation, membrane heat pump showed COP improved more than 20% of conventional system. This study modeled the heat and mass transfer of membrane heat pump in each process and analyzed heat exchanger operating principle by considering membrane’s vapor permeability for main two objects.

진공 멤브레인 제습 시스템의 운전 조건 변화에 따른 열역학적 성능 해석

임현정(Hyunjeong Lim),최상미(Sangmi Choi),정민규(Min Gyu Jung),이진욱(Jinwook Lee),김민성(Minsung Kim) 대한설비공학회 2019 대한설비공학회 학술발표대회논문집 Vol.2019 No.-

Cooling load is rapidly increasing due to improvement in the standard living and increase of average temperature in summer these days. Therefore, it is necessary to develop innovative technologies that can replace the conventional vapor compression cycle. A membrane heat pump can be one solution and vacuum membrane dehumidification is the main key of this device. In this paper, characteristics of vacuum membrane dehumidification (VMD) systems are introduced and dehumidification performance of each typical VMD systems are simulated thermodynamically. After this, results are compared and discussed in depth.

히트파이프 지중열교환기를 이용한 기후별 난방성능 해석

임현정(HyunJeong Lim),김찬중(Chan Joong Kim),오혜란(Hyeran Oh),김민성(Minsung Kim) 대한설비공학회 2016 대한설비공학회 학술발표대회논문집 Vol.2016 No.11

A ground-loop heat exchanger is one of the key components to collect low grade ground heat for a ground source heat pump system. A typical ground source heat pump consists of a refrigerant loop operated by a compressor and a geothermal brine loop operated by a circulation pump. Although ground source heat pumps are known as one of the most efficient HVAC devices, their performance still need to be upgraded since the energy consumption by the peripherals like the circulation pump are considerable and estimated more than 10% of the total electricity input. In order to reduce the ground circulation energy, a variety of researches such as direct expansion geothermal heat pumps are studied, but no apparent performance improvement was found due to other negative effects like the increase of pressure drop in the ground loop. Geothermal heat pipe can be a good alternative to replace ground-loop heat exchanger for heating purpose. The energy saving potential using heat pipe as ground heat exchanger was investigated. In a cold region, ground source heat pump with geothermal heat pipe can be a great choice to save energy.

호텔의 경험적 소비특성이 재방문의도와 전환의도에 미치는 영향

임현정(Hyunjeong Lim) 한국콘텐츠학회 2016 한국콘텐츠학회논문지 Vol.16 No.4

본 연구는 호텔기업에서 고객들이 경험하는 소비특성이 재방문의도와 전환의도에 어떤 영향을 미치는지 살펴보고, 또한 고객들의 방문횟수에 따라서 재방문의도와 전환의도에 미치는 영향력이 조절되는지 검증하여 마케팅 전략 측면에 실무적 시사점을 제공하고자한다. 이를 위해서 국내 특1, 2급 호텔을 이용한 고객534명을 대상으로 실증분석 하였고, 그 결과는 다음과 같다. 첫째, 호텔의 경험적 소비특성 중에서 유희성, 상징성, 유익성, 심미성이 재방문의도에 정(+)의 영향을 미치는 것으로 나타났다. 둘째, 호텔의 경험적 소비특성 중에서 상징성, 유익성, 심미성만이 전환의도에 부(-)의 영향을 미치는 것으로 나타났다. 더불어 재방문의도와 전환의도에 가장 큰 영향을 미치는 경험적 소비특성은 상징성임을 알 수 있었다. 셋째, 호텔의 경험적 소비특성 중 유희성, 공유성과 재방문의도의 영향관계는 방문횟수에 따라 조절되며, 호텔의 경험적 소비특성 중 유희성, 상징성과 전환의도와의 관계역시 방문횟수에 따라 조절되는 결과를 보였다. 이런 결과를 바탕으로 호텔기업에서는 효율적인 마케팅 전략을 수립할 수 있을 것이다. The purpose of this study is the findings of the effects of the experiential consumption characteristics in the hotel business on customers’ revisiting and switching Intention. Also, this study is to examine revisiting and switching intention in accordance with visit frequency. For this study, the author analyzed empirically 534 copies of questionnaires. The first finding of this study discovered that playfulness, symbolism, usefulness and aesthetics had positive effects on revisiting intention. Second, symbolism, usefulness and aesthetics had negative effects on switching intention. Especially, symbolism had more significant effect on revisiting and switching intention than other variables. And finally, visit frequency had moderating effects between the experiential consumption characteristics and revisiting intention, switching intention. The hotel companies are possible to obtain several strategic implications on the basis of this empirical results.

전주천 생태하천복원사업 후 이용자 평가 -환경특성 및 중요도, 만족도 분석을 중심으로-

임현정 ( Hyunjeong Lim ),이명우 ( Myungwoo Lee ),정문선 ( Moonsun Jeong ) 한국환경영향평가학회 2015 환경영향평가 Vol.24 No.3

본 연구의 목적은 전주천의 환경특성과 이용자 모니터링을 통한 구간별 하천관리방안 모색에 있다. 전주천 생태하천 복원구간의 환경특성으로 상류는 전주한옥마을과 인접하고 매우 좋은 수질과 자연하천경관을 갖고 있으며, 중, 하류는 수질상태가 양호하고 시설물이 집중되어 하천의 이용이 높은 구간이다. 설문을 통해 이용자특성, 이용행태, 시민참여, 중요도 우선순위, 중요도-만족도를 조사하였고, 설문응답 총 454부 중 무응답 완전제거 후 383부에 대한 인구 통계적 분석과 중요도-만족도 분석(Importance-Satisfaction Analysis: ISA)을 수행하였다. 그 결과 상, 중류는 60대 이상, 하류는 30~50 대의 이용률이 높고, 10분 이내, 도보권 이용자들이 운동을 목적으로 ‘혼자’, ‘계절과 관계없이’, ‘매일’ 혹은 ‘주 2~3회’ 방문하는 것으로 나타났다. ‘생태체험 활동’과 ‘하천지킴이 참여’는 ‘경우에 따라 참여’가 세구간 평균 78%로 나타났다. 중요도 우선순위에서 상, 하류는 ‘수질’ > ‘녹지연결’ > ‘산책로’, 중류는 ‘수질’ > ‘식물관리’ > ‘산책로’로 나타나 ‘수질’이 가장 중요함을 알 수 있었다. ISA 결과, 전 구간 10개 항목의 만족도(3.00)가 중요도(4.02)보다 낮아 개선이 필요하며, ‘우선시정’ 관리로 상류는 ‘식물 및 시설물관리’, 중, 하류는 ‘식물관리’, 전체 구간은 ‘식물관리’(I-S: 4.13, 2.89)로 나타났다. This study is to examine the section-based stream management with environmental characteristics and user monitoring. In Jeonjucheon, upstream section located near to Jeonju Hanok village has very good water quality and natural stream landscape. In case of mid/down streams, water quality is good and heavy concentration of facility leads to high use rates of these sections. The questionnaire consists of 5 parts: user characteristics, use behavior, citizen participation, importance rank, and Importance-Satisfaction(IS). 383 out of 454 responses with listwise deletion are used for demographic analysis and IS Analysis. In terms of citizen participation through ‘ecological experience activity’ and ‘stream stewardship activity’, ‘occasional participation’ shows the average of 78% in all three sections. For importance rank, the results arranged in order of priority show ‘water quality’ > ‘green corridor’ > ‘trail’ in up/down streams and ‘water quality’ > ‘vegetation management’ > ‘trail’ in midstream. Therefore, ‘water quality’ appears to be the most important variable among 13 variables. At last, the results of ISA indicate that all 10 variables need to be improved as satisfaction is lower than importance. In addition, ‘plant management’ variable falls into ‘concentrate here’ quadrant where importance is high and satisfaction is low.

다양한 구조의 진공 멤브레인 제습 성능에 관한 연구

임현정(Hyunjeong Lim),최상미(Sangmi Choi),정민규(Min Gyu Jung),김민성(Minsung Kim) 대한기계학회 2018 대한기계학회 춘추학술대회 Vol.2018 No.12

Membrane is a selective barrier which can separate one specific species from the mixture. An example of applying the membrane to air conditioning is vacuum membrane dehumidification. In this system, a vacuum compressor which is on one side of membrane creates pressure lower than another side. Therefore, water vapor in the humid air is separated when it passes the membrane module. There are three types of vacuum membrane dehumidification. Direct type is the simplest among them but the compressor outlet temperature is very high due to the high compression ratio. Bypass type and two modules type improve this problem. In this study, dehumidification COP of two models are compared in various compressor inlet pressure and climate conditions in detail.

효율적인 전산 장비 관리 시스템 설계 및 구현

임현정(Hyunjeong Lim),복경수(Kyoungsoo Bok),유재수(Jaesoo Yoo) 한국콘텐츠학회 2019 한국콘텐츠학회 종합학술대회 논문집 Vol.2019 No.5

방한 베트남 관광객의 정보탐색행동과 만족도에 관한 연구

임현정(Lim, Hyunjeong) 한국관광레저학회 2021 관광레저연구 Vol.33 No.8