• The Korean Journal of Ecology
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• 제9권1호
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• pp.33-40
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• 1986

The distribution of giant duckweed (Spirodela polyrrhiza) and small duckweed (Lemna aequinoctialis) was investigated at lead-zinc mine area and the limiting factors for their distribution were studied by laboratory experiments. The metal investigated of water affected on the growth of giant duckweed and small duckweed. Under filed conditions, both giant duckweed and small duckweed did not persist at more acidic conditions than pH 4.8 or at conditions more than 0.30 ppm of Cd concentration. Giant duckweeds were intolerable, under conditiions with less than 0.30 ppm of Cd and above than 0.07ppm of Zn, but small duckweeds were tolerable under conditions of more than 0.07 ppm of Zn concentration. However, neither can live above 7.50ppm of Zn concentration. These field observations corresponded with the results of the laboratory experiments.

• 대한두경부종양학회지
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• 제31권1호
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• pp.22-26
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• 2015

Small cell carcinoma of larynx has been reported as a rare disease occurring in 0.5% of larynx cancer. This tumor is known as one of the most lethal of all malignancies and associated with early recurrence and distant metastasis, leading into death. We experienced a case of a 70-year old male patient, who had admitted for sore throat and dysphagia and diagnosed as small cell carcinoma of larynx. We present small cell carcinoma of larynx with a brief review of literature.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.134-137
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• 2008

A methodology to evaluate the performance analysis for small hydropower at existing water treatment facilities has been studied. It consists of two main parts; flow duration function which can describe existing water treatment facilities and performance analysis to estimate the output characteristics of small hydro power plants. The output performance characteristics for Mi-ho reservoir, Sum-kang low dam, Sun-cheon sewage treatment plant and Nam-dong purification plant were analyzed, using developed model. According to the simulation results, the predicted data show that the data were in good agreement with measured results. Also, it was found that the developed model in this study can be used to analyze the output characteristics for small hydro power at existing water treatment facilities.

• 신재생에너지
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• 제2권2호
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• pp.81-85
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• 2006

The output performance characteristics for surveyed sites were analyzed, using developed model. It consists of two main parts, the deciding flow duration characteristic of river and performance prediction model to estimate the output characteristics of small hydropower plants. As a result, It was found that the flowrate concerning with 25% of time ratio on flow duration curve can be selected to design flowrate of small hydropower plants, and the output characteristics of small hydropower plants having overflow dam are different from large scale hydropower plants.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.1306-1307
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• 2011

Recently, the small scale photovoltaic (PV) electronic devices are drawing attention as the upcoming PV generation system. The PV system is commonly used in small scale PV applications such as LED lighting and cell phone. This paper proposes photovoltaic output sensorless (POS) maximum power point tracking (MPPT) control for a small scale charging system of PV-nickel metal hydride battery using field-programmable gate array (FPGA) controller. A converter is connected to a small scale PV cell and battery, and performs the POS MPPT at the battery terminal current instead of being at the PV cell output voltage and current. The FPGA controller and converter operate based on POS MPPT method. The experimental results show that the nickel metal hydride battery is charged by the maximum PV output power.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2009년도 학술대회
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• pp.301-309
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• 2009

This study focuses on event-driven social media (EDSM), which supports the production of unique cultural items of small groups by satisfying the conflicting desires of distinctiveness and assimilation that small groups possess. EDSM is a system which promotes the production of idioculture through small group interaction by using an actual event in which people participate in small groups. By setting up an EDSM system in a university festival in which 10,000 to 15,000 people gather in small groups, idioculture production was tested for approximately eight hours and a half. Interaction records gathered from the test, as well as focus group interview data garnered soon after were used to analyze usage patterns of EDSM, types of idiocultures produced, and resulting factors of user experience. Through this, considerations upon designing future EDSM were proposed.

• 한국압력기기공학회 논문집
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• 제8권1호
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• pp.1-7
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• 2012

A PHE (Process Heat Exchanger) is a key component required to transfer heat energy of $950^{\circ}C$ generated in a VHTR (Very High Temperature Reactor) to the chemical reaction that yields a large quantity of hydrogen. A small-scale PHE prototype made of Hastelloy-X is being tested in a small-scale gas loop at Korea Atomic Energy Research Institute. In order to properly evaluate the high-temperature structural integrity of the small-scale PHE prototype, it is very important to impose a proper constraint condition on its structural analysis model. For this effort, we tried to impose several constraint conditions on the structural analysis model and consequently fixed a proper and effective displacement constraints.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 춘계학술대회 논문집 전력기술부문
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• pp.166-168
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• 2001

Generation by the privately owned generators, which are normally operated has occupied about 10% of total generation. Recently the small co-generation employed gas engine has been introduced and attracted public interest. For privately owned generator to be paralleled Utilities, a customer complies with Generator Parallel Operation Guideline set by Utilities and installs related protective relays. But the guideline is not specified to small co-generation, only provides parallel operation of privately owned generator. So applying this guideline, initial investment can be too high comparing to total co-generation cost. Besides there is no specified guide about ALTS, which arises asynchronous problem. In this paper we analyzed guideline and technical problem when small co-generation is paralleled. And additionally needed researching area to improve distribution of small co-generation is discussed.

• 한국임상수의학회지
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• 제31권1호
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• pp.61-65
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• 2014

The study aimed at determining the feasibility of three portal totally Laparoscopic cryptorchidectomy in small breed dogs. Four right sided and one left sided abdomen retained testicles in five dogs weighing 2.2~8.7 kg were retrieved successfully. Pampiniform plexus and vas deference were ligated and transected with Hem-o-lock/monopolar electrocauterization (1/5), or ultrasonic scalpel (4/5) and the latter provided more easy, quick and safe hemostasis and transection. The resected testis was easily removed through a insertion site. Mean surgical time was $19.9{\pm}15.2$ minutes and when the abdominal cavity was explored again, there were no major complications. The patient recovered favorably without unwilling events. This is the case report of laparoscopic cryptorchidectomies in small breed dogs weigh less than 10 kg. Laparoscopic cryptorchidectomy could be considered as an alternative in small animal surgery.

• 한국가스학회지
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• 제19권1호
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• pp.51-56
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• 2015

To assess downward positions of water spray for the small-scale release of chlorine gas, dispersion coefficients for the Gaussian dispersion model were validated at the small-scale release experiment. And the downwind distances of water spray were assessed with the simulated results. As results, the Gaussian plume model using the Briggs' dispersion coefficient well estimated the dispersed characteristics for small-scale release of chlorine gas. The best adequate downwind position of water spray is the position of the maximum concentration of chlorine at the ground level. And the adequate vertical and horizontal dimensions of water spray consider the maximum width and height of cloud.