• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.9
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• pp.31-39
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• 2011

In this paper, we propose a signal readout system with small area and low power consumption for CNT sensor arrays. The proposed system consists of signal readout circuitry, a digital controller, and UART I/O. The key components of the signal readout circuitry are 64 transimpedance amplifiers (TIA) and SAR-ADC with 11-bit resolution. The TIA adopts an active input current mirror (AICM) for voltage biasing and current amplification of a sensor. The proposed architecture can reduce area and power without sampling rate degradation because the 64 TIAs share a variable gain amplifier (VGA) which needs large area and high power due to resistive feedback. In addition, the SAR-ADC is designed for low power with modified algorithm where the operation of the lower bits can be skipped according to an input voltage level. The operation of ADC is controlled by a digital controller based on UART protocol. The data of ADC can be monitored on a computer terminal. The signal readout circuitry was designed with 0.13${\mu}m$ CMOS technology. It occupies the area of 0.173 $mm^2$ and consumes 77.06${\mu}W$ at the conversion rate of 640 samples/s. According to measurement, the linearity error is under 5.3% in the input sensing current range of 10nA - 10${\mu}A$. The UART I/O and the digital controller were designed with 0.18${\mu}m$ CMOS technology and their area is 0.251 $mm^2$.

• Ecology and Resilient Infrastructure
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• v.6 no.2
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• pp.79-88
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• 2019

In order to study the water quality status and its causal environmental factors, the water quality variables of chemical oxygen demand (COD), chlorophyll a (Chl a), Total phosphorus (TP), and total nitrogen (TN), the hydrogeomorphologic variables of water level fluctuation, total water storage, dam elevation, watershed area, and shoreline development index, and the land cover variables of forest, agricultural area, and urbanized area in the watershed were investigated in total 73 reservoirs with various operational purposes, water level fluctuation and geographical distribution in South Korea. The water quality was more eutrophic in the reservoirs of the more urbanized and agricultural area in the watershed, the low altitude, the narrow water level fluctuation, the narrowed watershed area, and the more circular shape. In terms of the purposes of reservoir operation, the reservoirs for agricultural irrigation were more eutrophic than the reservoirs for flood control. The results of the variable selection and path analysis showed that COD determined by Chl a and TP was directly affected by water level fluctuation and the shoreline development of the reservoirs. TP was directly affected by the urbanized area of the watershed which was related to the elevation of the reservoir. TP was also influenced by the water level fluctuation and the shoreline development. In conclusion, the eutrophication of the reservoirs in Korea would be influenced by the land use of the watershed, hydrological and geographical characteristics of the reservoir, water level fluctuation by the anthropogenic management according to the reservoir operation purpose, and the location of the reservoirs.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.1
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• pp.27-34
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• 2010

In a test duct with closed configuration, particle removal performance of an edge-plate type electrostatic precipitator (ESP) was evaluated at a high flow rate in $CO_2$ rich environments by changing gap distances between collection plates, concentrations of $CO_2$, particle sizes, types of electrodes, and types of power supplies. At the same experimental conditions, collection efficiency of particles with the mean particle size, 300 nm, decreased as the gap distance and $CO_2$ concentration increased because of low electrostatic force and low discharged current. In addition, as the particle size increased, the efficiency increased because of high charging rate of the large particles. With the electrode type which has higher surface area of a discharging plate and with the power supply which applied 25 kHz-pulsed DC voltages, the removal efficiency was high even in rich $CO_2$ condition due to high electrostatic force at the same power consumption.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.549-558
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• 2017

The aim of this study was to analyze the effects of aerobic exercise on the blood lipids, leptin, ghrelin, and HOMA-IR factors in obese postmenopausal Korean women. Thirty-six healthy postmenopausal women (mean age, $54.47{\pm}2.50$ years) with >32 % body fat were assigned randomly to an aerobic exercise group (n = 18) or to a "no exercise" control group (n = 18). The subjects' body composition, blood lipid, leptin, ghrelin levels, and HOMA-IR were measured before and after a 16-week line-dancing program. The exercise group showed a significant decrease in body weight, percent body fat, body mass index, visceral fat area, leptin, insulin, glucose, HOMA-IR, total cholesterol, triglycerides, apolipoprotein B, low-density lipoprotein cholesterol, and systolic and diastolic blood pressure. In addition, this group exhibited a significant increase in the apolipoprotein A-I, ghrelin, and high-density lipoprotein cholesterol levels. The energy metabolic factors that influenced the visceral fat included ghrelin, leptin, insulin, glucose, and HOMA-IR. The t-value, which determined the statistical significance of the independent variables, was significant for ghrelin, glucose, insulin, and HOMA-IR (p < 0.05). Regular and continuous aerobic exercise (e.g., line dancing) effectively improved the body composition, visceral fat, serum blood lipids, leptin, ghrelin, and HOMA-IR factors in obese postmenopausal Korean women.

• Journal of Korea Water Resources Association
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• v.48 no.9
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• pp.719-728
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• 2015

In this study, urban runoff analyses were performed using high resolution Quantitative Precipitation Estimation (QPE), and variation of rainfall and runoff were analyzed to evaluate QPE data for urban runoff analysis. The five drainage districts (Seocho3, 4, 5, Yeoksam and Nonhyun) around Gangnam station were chosen as study area, the area is $7.4km^2$. Rainfall data from KMA AWS (34 stations), SKP AWS (156 stations) and Gwanduk radar were used for QPEs in Seoul area. Four types of QPE(QPE1: KMA AWS, QPE2: KMA+ SKP AWS, QPE3: Gwangduk radar, QPE4: QPE2+QPE3) of 6 events in July 2013 were generated by using Krigging and conditional merging. The temporal and spatial resolution of QPEs are 10 minutes and 250 m, respectively. The complex pipe network were treated as 773 manholes, 772 sub-drainage districts and 1,059 pipelines for urban runoff analysis as input data. QPE2 and QPE4 show spatial variation of rainfall by sub-drainage districts as 1.9 times bigger than QPE1. The peak runoff of QPE2 and QPE4 also show spatial variation as 6 times bigger than Gangnam and Seocho AWS. Thus, the spatial variation of rainfall and runoff could exist in small area such as this study area, and using high-resolution rainfall data is desirable for accurate urban runoff analysis.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.641-651
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• 2022

This research compares and analyzes evacuation time depending on the change in stair width in case of fire at Goshiwons. For this, a simulation has been conducted based on possible evacuation time according to the calculation method for the number of people admittable to a specific target for fire fighting equipped with accommodation. Currently, Gosiwon, which is classified as an accommodation facility (a total floor area of 500 m² or more), uses blind spots prescribed by the Fire Services Act, Building Act, and Parking Act to build a high-rise building on a small area of land, and most Gosiwon is transformed into a modified accommodation. This is in line with the owner's operating profit, so it is expected to show a continuous increase. Securing the golden time of Gosiwon evacuation time is the last bastion of Gosiwon residents who belong to the economically disadvantaged in our society, and we hope this study will serve as a starting point for discussions on revising related laws and regulations to establish a social safety net As a result of the evacuation simulation analysis, the evacuation time was the least when the width of the group and the evacuation stairs were expanded to 200cm, and the evacuation time of the existing building was reduced by up to 166.3 seconds by comparing 648.4 seconds and scenario 6. This analysis can be meaningful, in that the width of the evacuation stairs revision of related laws and regulations for the safety of multiplex available premises.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.737-742
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• 2005

본 연구는 GIUH(Geomorphologic Instantaneous Unit Hydrograph) 매개변수와 유역의 지 형특성 인자인 유역면적, 유로연장, 유로경사의 상관성을 분석하여 유역면적과 유로연장의 GIUH 매개변수와의 상관식을 유도하였다. 그리고 대상유역의 Fractal분석도 실시하여 지형상사를 확인하였다. 상관식의 검증을 위해 설마천 유역을 선정하여 결과를 실측치를 계산치와 수정치로 비교하고 계산치와 수정치도 비교하였다. 본 연구의 결과로 산정된 상관식을 사용하여 임의의 미계측 유역의 GIUH매개변수를 산정할 경우 기존의 복잡하고 시간이 많이 소요되는 GIS작업의 번거로움을 최소화할 수 있을 것이다.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.6 no.11
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• pp.52-62
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• 1985

우리나라의 논면적은 132만 정보로써 전 경지면적의 60.7$\%$에 해당되며 우리국민의 주식인 쌀을 생산하는 터전이다. 벼를 씨뿌린 후 수확하기까지는 약6개월이 소요되지만 본답에 이앙하고부터는 4개월이면 충분히 벼를 수확할 수 있기 때문에 나머지 8개월동안 논토양을 어떻게 이용하느냐에 따라서 농가경제는 물론 국가의 식량생산에도 큰 영향을 주게된다. 또한 단위면적당 벼 수량을 높이기 위하여는 토양조건을 벼가 자라는데 부족함이 없도록 만들어 주어야 되는데, 비료나 농약 등은 벼가 자라는 기간에 뿌릴 수 있지만 논을 깊이 갈이한다거나 배수시설 등은 벼 생육기간에는 작업이 불가능하므로 벼를 수확한 후에 계획하지 않으면 안된다. 이제 여러 가지 어려운 여건속에서도 연속 5년간 대풍을 이룬 논토양을 농한기동안 어떻게 이용하고 어떻게 관리해야 되는가에 대하여 소개하기로 하겠다.

• Korean Institute of Interior Design Journal
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• v.14 no.2 s.49
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• pp.128-134
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• 2005

This dissertation is about a study on the space planning of take-out coffee shops grouped by type. The classification is based primarily on stand-alone shop, which runs independently, and shop in shop, located inside of another shop with different industry. And its subdivision is characterize by 3 types: Combination type has not only space to enjoy coffee as we can usually see in conventional coffee shops, but also a counter where take-out coffee is served. Separation type has space for drinking coffee and an external booth for easy buy. Booth type is a booth itself or driving (cruising) booth. In conclusion, some take-out coffee shop are exampled and space analysis is made with analytic tools, such as people of preference, location evaluation, functional space division, dimension per person, and planning of traffic line.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.04a
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• pp.54-56
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• 2002

고추는 국내 재배면적이 노지재배가 75,000 ha 정도로서 해마다 조금씩 감소하고 있고, 시설재배가 5,000 ha 정도로서 해마다 증가하고 있다. 따라서 약 80,000 ha 의 재배 면적을 매년 심어야 하기 때문에 원예작물 가운데 가장 많은 모종을 필요로 한다. 이를 뒷받침하기 위하여 공정육묘에서 차지하는 비율이 60%를 넘고 있다. 고추종자는 발아적온이 28-3$0^{\circ}C$ 정도로 알려져 있으며 발아소요일수가 2-3일 정도로서 발아적산온도는 1,300~1,450$^{\circ}$ 정도로 알려져 있다. (중략)