• 대한의용생체공학회:의공학회지
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• 제28권3호
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• pp.387-391
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• 2007

An oxygenator is a very important artificial organ and widely used for patients with lung failure or during open heart surgery. Although an oxygenator has been widely studied worldwide to enhance its efficiency, studies on oxygenators, in particular when using a pulsatile blood flow, are domestically limited. Therefore, a new oxygenator was developed in the lab and animal experimental results are described in the paper. The oxygenator is composed of polycarbonate housing and polypropylene hollow fibers. It has a total length of 400 mm and a surface area of $1.7 m^2$. The animal experiment lasted for 4 hours. The blood flow rate was set to 2 L/min and a pulsatile blood pump, T-PLS (Twin-Pulse Life Support), was used. Samples were drawn at the oxygenator's inlet and outlet. The total hemoglobin (Hb), saturation oxygen ($sO_2$), and partial oxygen pressure ($pO_2$), partial $CO_2$ pressure ($pCO_2$), and plasma bicarbonate ion concentration ($HCO_3^-$) were measured. The oxygen and carbon dioxide transfer rates were also calculated based on the experimental data in order to estimate the oxygenator's gas transfer efficiency. The oxygen and carbon dioxide transfer rates were $16.4{\pm}1.58$ and $165.7{\pm}10.96 mL/min$, respectively. The results showed a higher carbon dioxide transfer rate was achieved with the oxygenator. Also, the mean inlet and outlet blood pressures were 162.79 and 137.92 mmHg, respectively. The oxygenator has a low pressure drop between its inlet and outlet. The aim of own preliminary study was to make a new oxygenator and review its performance when applying a pulsatile blood pump thus, confirming the possibility of a new oxygenator suitable for pulsatile flow.

• 한국환경복원기술학회지
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• 제20권6호
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• pp.1-19
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• 2017

This study set out to identify problems with amphibian habitation by the wetland types and improve their habitation environment in urban forest wetlands, thus creating a habitat for amphibians. Study site include forest swamps in Jatjul Park as well as Yeoji neighborhood Park in Guro-gu, and in Choansan neighborhood Park in Dobong-gu. The forest swamp in Jatjul Park gets its water from Mt. Maebong and it is a former escalated farmland-turned wetland. The swamp area is $2,500m^2$, a forest zone and a landscape planting site are 83.27% and 6.70% each. Target species Seoul pond frogs are inseparable from rice fields because they live in a short radius of and lay eggs in or near paddy fields, and Rana nigromaculata have similarities with Rana plancyi chosenica in choosing their habitats. There was need for paths that would lead to other paths so amphibians would spread to other parts of the forest and for measures to secure open water. Modifying a variety of routes for water, human and animals along with building a buffer to keep the core habitation zones were required. The forest swamp in Yeonji neighborhood Park used to be a water reservoir on the foot of Mt. Gunji. The swamp area is $1,980m^2$, a forest zone and farmland account for 80.61% and 4.88% each. Non-point pollutants from upstream along run into the subject forest marsh, bare ground on the around swamp and steep stone embankments obstructed amphibians. Target species was Bufo gargarizans that live in forests and edges of hills and spawn in deep water. The forest swamp in Choansan neighborhood Park gets its water from Mt. Choan and it is close to its water source that it is a mountain stream forest wetland. The basin and the swamp are $35,240m^2$ and $250m^2$ in size respectively. A forest zone accounts for 90.20%, high stone embankments laid in refurbishing the valley obstruct amphibians and there is water shortage in times of droughts. Target species were Rana coreana, Rana dybowskii and Hynobius leechii that live in mountain valleys, streams and wetlands and lay eggs in forest marshes and rocks in valleys. Looking into the three swamps of amphibian habitation, I came to conclusions that those wetlands were suitable for their amphibians but man-made facilities blocked their corridors leading to other corridors and even killed off target species in some parts of those swamps by destroying those parts. Amphibians live in water, on ground and underground at different stages of life. Hence, we should take this fact into consideration when planning their habitats and design core habitation zones, buffers zone and use zones accordingly. Buffer zones ought to be between core habitation zones and surrounding trees. Aiming at protecting core habitation zones, buffers should be in harmony with habitation zones. Use zones should be minimized in size and not in direct contact with core habitation zones.

• 대기
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• 제23권1호
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• pp.93-102
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• 2013

Atmospheric transport pathway of an air mass is an important constraint controlling the chemical properties of the air mass observed at a designated location. Such information could be utilized for understanding observed temporal variabilities in atmospheric concentrations of long-lived chemical compounds, of which sinks and/or sources are related particularly with natural and/or anthropogenic processes in the surface, and as well as for performing inversions to constrain the fluxes of such compounds. The Lagrangian particle dispersion model FLEXPART provides a useful tool for estimating detailed particle dispersion during atmospheric transport, a significant improvement over traditional "single-line" trajectory models that have been widely used. However, those without a modeling background seeking to create simple back-trajectory maps may find it challenging to optimize FLEXPART for their needs. In this study, we explain how to set up, operate, and optimize FLEXPART for back-trajectory analysis, and also provide automatization programs based on the open-source R language. Discussions include setting up an "AVAILABLE" file (directory of input meteorological fields stored on the computer), creating C-shell scripts for initiating FLEXPART runs and storing the output in directories designated by date, as wells as processing the FLEXPART output to create figures for a back-trajectory "footprint" (potential emission sensitivity within the boundary layer). Step by step instructions are explained for an example case of calculating back trajectories derived for Anmyeon-do, Korea for January 2011. One application is also demonstrated in interpreting observed variabilities in atmospheric $CO_2$ concentration at Anmyeon-do during this period. Back-trajectory modeling information introduced in this study should facilitate the creation and automation of most common back-trajectory calculation needs in atmospheric research.

• 한국의료질향상학회지
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• 제2권2호
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• pp.156-171
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• 1996

Background: Nosocomial infection control is one of important means to assure the quality of medical care in the hospital, however, it has been neglected by most of the hospital personnels. Of nosocomial infections, urinary tract infection is the highest incidence, which is related to the indwelling catheter. It is, therefore, necessary to pay primary attention to the patients with the indwelling catheter in intensive care unit in order to control nosocomial Infection and to improve the quality of medical care in the hospital. Methods : The subjects of this study were patients with indwelling catheter who were admitted to the ICU of Pusan Paik Hospital from March 1994 to May 1995. The author calculated UTI rate among the subjects through the cultivation of the urine, identified the related factors of the UTI through brain storming of study team and head nurses working at ICU, and analized the effectiveness of the proposed approaches through comparing the infection rates of before and after activities. Results : The major activities carried out by the study team were to conduct in-service education programs for the staffs working at ICU about the importance of the nosocomial infection control in QA, and nursing intervention to reduce the UTI rate among the patients with indwelling catether. 1. The major nursing interventions that the study team had implemented were as follows ; 1) Drainage system was changed from partial open system to completely closed system. 2) Bladder irrigation which was routinely practised in all patients stopped among the noninfected patients. 3) Bladder irrigation set was changed to the disposable one. 4) Catheter was inserted under the anesthesia for patients to be operated. 5) Male patient receiving wrapped with gauze after perineal care was not wrapped. 6) Clamp which had not been before was newly attached to drainage tube. 7) Urine bag which had been packed into a lot of pieces was done into each piece. 8) The interval of change of indwelling catheter had regularly been four weeks, however it was used continously until it worked well. 9) Catheter was attached well at the defined site. 10) Paper towel was used instead of cotton towel. 11) Mats at the entrance were removed and cleansing of wards was enhanced. 2. The UTI rate by month was 34.4% in maximum and 9.8% in minimum during the period of this study, however it had gradually decreased. After 6 months from initiating infection control activities, the trend of rates was relatively stable. It was identified that UTI rate was different by season 12.5% in winter and 27.2% in summer. 3. Utilization rate of indwelling catheter was maintained at under 50%, but it was increased above 57% from April 1995. 4. The number of bladder irrigation sets used per day was 33.3 sets in maximum and 2.8 sets in minimum. The number used per day were also remarkably deceased. Conclusion : It was found that a program to control UTI could contribute to nosocomial infection control, and it was, in turn, a mean to assure the quality of medical care in the hospital. The nursing interventions which this study team had implemented were effective in the reduce of UTI rates.

• 한국콘텐츠학회논문지
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• 제10권6호
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• pp.286-296
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• 2010

DJ로봇 개발을 위한 연구는 디지털과 네트워크의 시대를 맞이하여 매우 빠른 속도로 변화하고 있는 대중들의 음악 서비스 요구에 부응하기 위한 것이다. 기존의 연구들은 대체적으로 개인화된 환경, 개인화된 장비를 전제로 음악 서비스 개발에 나서고 있지만 DJ로봇은 공공이 공유하는 공간을 전제로 삼고 있다. DJ로봇은 우리나라 전통적 공간과 전통 음악을 우선적으로 한다. 최근 한국 문화에 대한 외국의 호의와 수요가 확대됨에 따라 우리 전통 혹은 고유한 특질에 기초한 콘텐츠의 산업적 활용 가치가 점점 높아지고 있기 때문이다. 한편, DJ로봇은 외부 환경 변화를 감지하는 방식과 심리학, 감성공학 등에 의한 음악의 속성을 설정하는 방식의 결합으로 구성되어 있다. 설치 공간의 온도, 습도, 조도, 풍속, 소음 등의 환경 요소를 측정 및 적용하고 헤브너의 감성분류법에 기초하여 감성공학에 의한 반복적인 실험과 검증을 통해 음원의 객관성을 확보할 것이다. DJ로봇은 전통 공간의 사운드스케이프를 아름답게 변화시키는 동시에 수용자 감성과 연계된 전통음악 BGM의 활용을 통하여 아직까지 극소수 사람들 사이에서만 소통되고 있는 전통음악을 보다 다양하고 적극적인 기능을 지닌 문화콘텐츠로 재탄생 시키는 일에 기여할 것이다.

• 한국정보과학회논문지:소프트웨어및응용
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• 제37권1호
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• pp.60-73
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• 2010

본 연구의 목적은 한국어 수분류사 체계를 설정하고, 수분류사와 공기명사 간 의미관계 정보를 제공하는 한국어 수분류사 어휘의미망 "KorLexClas 1.5"의 정보구조와 구축방식을 소개하는 데 있다. KorLex 명사, 동사, 형용사, 부사가 영어 워드넷(Princeton WordNet)을 기반으로 참고구축 방식으로 개발된 것에 비해, KorLexClas 1.0버전과 이를 확장한 1.5버전은 직접구축 방식으로 개발하였다는 점에서, 수분류사의 계층구조와 언어단위 간 의미관계 설정은 매우 방대한 시간과 정교한 구축 방식을 요구한다. 따라서 작업의 효율성을 기함과 동시에, 구축된 어휘의미망의 신뢰성 및 확장성을 높이기 위해, (1) 다양한 기구축 언어자원을 활용하되 상호 검증하는 절차를 거치고, (2) 부분문장 분석방법을 이용하여, 수분류사 및 공기명사 목록을 확장하며, (3) 언어학적 준거를 기준으로 수분류사의 계층구조를 설정하고, (4) 수분류사와 공기명사 간 의미관계 정보를 제공하되 확장성을 확보하기 위해, KorLexNoun 1.5에 '최하위 공통상 위노드(LUB : Least Upper Bound)'를 설정하는 방식을 택한다. 이러한 특성을 가진 KorLexClas 1.5는 기계번역을 비롯한 한국어정보처리의 제 분야에 응용될 수 있다.

• 유통과학연구
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• 제12권10호
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• pp.123-128
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• 2014

Purpose - The purpose of the study is to reexamine the price fairness as practiced by low cost airlines, as a consumer has to experience such inconveniences as inferior airport transportation, extra fees on in-flight meals, and non-negotiable seats, and consumers evaluate such experiences keeping in mind their total costs. This evaluation includes price fairness and allows a reasonable and overall consideration of factors of low cost airlines. It tries to set up a measurement of the indicators consumers' perceptions of price fairness academically as it adapts price fairness to airline services which are renowned for price volatility. Research design, data, and methodology - The research proposes an alternative pricing strategy for the long term profit of low cost airlines after going over conflicts between the traditional theory of consumers' price perception mechanism and flexible fair policy of low cost airlines. It was meaningful when it relates to the early stage of the business, while it enhances the risks relating to the long term survival of low cost airlines. In addition, it is significant as it highlights the negative influences on consumers' perceptions of price fairness, as low cost airlines run on extremely low cost perspectives. Results - The results of the research provide insight into four perspectives, as consumers' perceptions of price fairness are influenced by the frequency and range of price changes and services. The first perspective is that it would lead to positive price evaluation when a low cost airline cuts prices frequently with little changes than one big change. It also would lead to the same result when it comes to necessary services. The second perspective is that one big increase of price would rather undermine the negative aspects of price changes than those of several smaller ones. The third perspective is that additional services would be good to consumers' perceptions of price fairness as compared to discount benefits with respect to the cost. Finally, a low cost airline should consider that consumers will change airlines or defer their flight schedule if the flight fares increase beyond their limits. Conclusions - Low cost airlines should reconsider their pricing policies for services that were provided free earlier. A consumer would not like discount benefits when made to pay for services that were, for long, free of charge. If a low cost airline can provide services with no charge, it should improve volumes if the costs are standardized and, moreover, should consider the charging fees. Alternatively, a consumer can choose between services and fair discount. Low cost airlines are implementing sales promotion strategies, as the competition is more intense than it used to be. In these days, they should regard services over sales promotion, as consumers may prefer to spend money on good premium services. Some differentiation in services could create a good market position for the airlines and, hence, good financial performance.

• 한국산학기술학회논문지
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• 제17권7호
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• pp.154-164
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• 2016

본 논문은 최근 사회적 이슈가 되고 있는 감정 노동자의 이직의도 결정 요인에 관한 연구로서, 서비스 산업에 종사하는 감정 노동자의 서비스 품질 향상에 영향을 미치는 이직 의도를 결정하는 요인이 무엇인지에 대해 실증적인 연구를 통해 조사 분석한 것이다. 독립 변수로 설정한 감정 노동자의 직무특성 및 직무환경, 조직문화, 감정노동행위 등이 종속 변수인 이직 의도에 어떤 영향을 미치는지 실증 조사하였으며, 이러한 독립 변수들이 직무만족을 매개로 감정 노동자의 이직 의도에 어떻게 영향을 미치는지에 대해 실증적으로 살펴보았다. 연구 대상으로는 주로 강원권의 대형 숙박 서비스업에 종사하는 감정 노동자를 대상으로 하였으며 직무특성 및 직무환경 요인 중에서는 직무다양성 요인과 내외적 보상 요인이 이직 의도에 영향을 미치고 있었고, 조직문화 요인으로는 인적 자원 문화, 개방 체계 문화, 위계 질서 문화 요인이 이직의도에 영향을 미치고 있었으며, 감정노동 행위 중에서는 표면행위, 진심행위 요인이 이직의도에 영향을 미치고 있는 것으로 실증적으로 조사되었다. 또한 직무만족을 매개로 한 가설검증에서는 직무다양성 요인 등 몇몇 요인들이 영향을 미치고 있었으며, 향후에는 독립변수 요인으로 정규직 비정규직 여부를 하나의 요인으로 두고 실증조사를 해보면 좀 더 유익한 결론을 얻을 수 있을 것 같다.

• 지능정보연구
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• 제24권3호
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• pp.45-66
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• 2018

크라우드펀딩(Crowdfunding)은 최근 벤처 기업의 기금 모금을 위한 엔젤 기금보다 인기가 있다. 이에 따라 크라우드펀딩의 성공 요인을 파악하는 것은 기금 조성자 및 투자자로 하여금 크라우드펀딩 프로젝트와 관련된 효과적 의사결정을 내리기 위해 크라우드펀딩 성공 여부를 선험적으로 예측하는데 유용할 것이다. 이에 최근까지 프로젝트의 목표 및 관련 SNS의 수와 같은 몇 가지 수치적 요인을 독립변인으로 제안하여 이들이 크라우드펀딩 캠페인의 성공에 어떤 영향을 미치는지 등이 연구되어오고 있었다. 그러나 수치가 아닌 비정형 데이터를 통한 크라우드펀딩 캠페인의 성공에 대한 예측은 거의 이루어진 바 없으며, 특히 프로젝트를 소개하는 문서에 대한 특성 분석을 통해 해당 프로젝트의 성공여부를 예측하려는 연구는 아직 이루어지지 않았다. 사실 프로젝트를 소개하는 문서는 공개되어 있어 확보에 드는 비용이 적게 들기 때문에 매우 유용하다. 따라서 본 연구의 목적은 Wadiz 등 온라인상으로 공개되어 있는 프로젝트에 대한 소개 문서를 기반으로 크라우드펀딩 프로젝트의 성공을 예측하는 새로운 방법을 제안하는 것이다. 제안된 방법의 성능을 테스트하기 위해, 본 연구에서는 1,980개의 실제 크라우드펀딩 프로젝트와 관련된 텍스트를 수집하고 경험적으로 분석했다. 텍스트 데이터 세트에서 카테고리, 응답 수, 자금 조달 목표, 기금 모금 방법, 보상, SNS 추종자 수, 이미지 및 비디오 수 및 기타 숫자 데이터와 같은 프로젝트에 대한 세부 정보를 수집하였다. 분석 결과 이러한 요인들은 분류 알고리즘에서 분류 성능을 제고하는데 의미 있는 변인으로 확인되었다. 즉, 제안된 방법이 최근에 제안된 비정형 텍스트 기반 방법보다 정확도나 F-점수 및 수행 경과 시간에서 성능이 우수하였다.

• 한국조경학회지
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• 제18권4호
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• pp.45-71
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• 1991

The landscape systems in Korean island settlements can be recognized as results of ingabitants' ecological adptation to the isolated environment with the limited natural resources. Both the fishery dominant industry in island society and ecological nature of its environments seem to have influenced on inhabitants' environmental cognition as well as the physical landscape of island villages such as its location, spatial pattern in each village, housing form and so on. This study was done mainly by both refering to the related documents and direct observations in case study areas, and results of the study can be summarized as follows. 1. In general, the landscape of an individual island seems to take more innate characteristics of island's own, corresponding to the degree of isolation from mainland. That is, while the landscape of island in neighboring waters takes both inland-like and island-innate landscape character at the same time, the one in the open sea far from land takes more innate landscape character of all island's own in the aspects of village location, land use and housing density etc. 2. The convex landform of most islands brings about more centrifugal village allocation than centripetal allocation in most inland villages. And thus most villages in each island face extremely diverse directions different from the south facing preference in most inland rural villages. 3. Most island villages tend to be located along the ecologically transitional strip between land and sea, so called 'line of life', rather than between hilly slope and flat land as being in most inland village locations. So they are located with marine ecology bounded fishing ground ahead and land ecology bounded agricultural site at the back of them. 4. The settlement pattern of the island fishing villages shows more compact spatial structure than that of inland agricultural villages, due to the absolute limits of usable land resources and the adaptation to the marine environment with severe sea winds and waves or for the easy accessability to the fishing grounds. And also the managerial patterns of public owned sea weed catching ground, which take each family as the unit of usership rather than an individual, seem to make the villagescape more compact and the size of Individual residence smaller than that of inland agricultural village. 5. The folk shrine('Dand') systems, in persrective of villagescape, represent innate environmental cognition of island inhabitants above all other cultural landscape elements in the island. Usually the kinds and the meanings of island's communal shrine and its allocative patternsin island villagescape are composed of set with binary opposition, for example 'Upper shrine(representing 'earth', 'mountain' or 'fire')' and 'Lower Shrine(representing 'sea', 'dragon' or 'water') are those. They are usually located at contrary positions in villagescape each other. That is, they are located at 'the virtical center or visual terminus(Upper shrine at hillside behind the village)' and 'the border or entrance(Lower Shrine at seashore in front of the village)'. Each of these shirines' divinity coincides with each subsystem of island's natural eco-system(earth sphere vs marine sphere) and they also contribute to ecological conservation, bonded with the 'Sacred Forest(usually with another function of windbreak)' or 'Sacred Natural Fountain' nearby them, which are representatives of island's natural resources.