• 대한토목학회논문집
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• 제4권4호
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• pp.137-145
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• 1984

타일랜드 북동부(北東部) 세 지역(地域)에서 나타나는 이산토(離散土)에 대한 물리적(物理的) 화학적(化學的) 특성(特性)에 대(對)한 시험(試驗)이 실험실(實驗室)과 현장(現場)에서 수행(遂行)되었다. 이산토(離散土)의 점토함량(粘土含量)과 이산성(離散性)과의 관계(關係)를 구명(糾明)하기 위(爲)하여 실내(室內)에서 이산토중(離散土中)의 점토(粘土) 분리(分離)한 후(後) 인위적(人爲的)인 점토함량비(粘土含量比)로 흙을 다시 만들어서 pinhole 시험(試驗)을 수행(遂行)하였는데, 이산토(離散土)는 점토함량비(粘土含量比)에 관계(關係)없이 쉽게 이산(離散)되었다. 또한 흙의 추출수(抽出水)와 저수지(貯水池) 물에 대한 화학적(化學的) 특성(特性)을 밝히기 위하여 SA,R, ESP 및 pH 값들이 결정(決定)되었는데, 이산토(離散土)는 1.8~6.7 SAR, 1.4~7.9 ESP 및 5.4~9.0의 pH 값을 나타내어서 일반적(一般的)인 흙에 비(比)하여 높은 SAR, ESP 및 pH 값을 보였다.

• 한국대기환경학회지
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• 제12권3호
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• pp.243-254
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• 1996

The main purpose of this study is to investigate the collection efficiency characteristics of a cylindrical ESP. To do that, it is necessary to analyze the electric field, gas flow field, and mechanism of particle movement by numerical simulation based on EHD model. For a gas flow field, Navier-Stokes equation involving the electric source term was solved by SIMPLE algorithm. In case of the electric field, the current continuity and electric field equations were solved by S.O.R. method. The analysis of particle movement was performed on the basis of PSI-CELL model from the Lagrangian viewpoint. The results showed that the influence on the gas flow field by the electric field is almost negligible in a cylindrical ESP. The particle drift velocity $V_P$ toward the collection surface is increased continuously by the electrostatic force due to the rise of particle charge as the particle is moving to the flow direction and the particle size becomes larger. The collection efficiency is to quitely higher with the increase of applied voltage for the same particle size, while becomes smaller as the inlet velocity is increased.

• International Journal of Computer Science & Network Security
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• 제22권8호
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• pp.1-6
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• 2022

In this paper, we will present the realization of a facial recognition system using the ESP32-CAM board controlled by an Arduino board. The goal is to monitor a remote location in real time via a camera that is integrated into the ESP32 IOT board. The acquired images will be recorded on a memory card and at the same time transmitted to a pc (a web server). The development of this remote monitoring system is to create an alternative between security, reception, and transmission of information to act accordingly. The simulation results of our proposed application of the facial recognition domain are very efficient and satisfying in real time.

• Journal of Microbiology and Biotechnology
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• 제13권3호
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• pp.400-405
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• 2003

A gene (hpkA), encoding a histidine protein kinase homolog, has been identified in the upstream region of the espAB operon in Myxococcus xanthus. It encodes a 333 amino acid (35,952 Da) protein with a histidine protein kinase domain in the region from amino acid 90 to 317. Null mutations in the hpkA gene caused formation of loose irregular fruiting bodies, while wild-type strains developed tight hemispherical fruiting bodies under developmental conditions. Sporulation of the hpkA mutant was delayed by at least 12 h compared to that of the wild-type. It appeared that the hpkA mutation increased the expression of the espAB operon by more than 2-fold compared with the wild-type under developmental conditions. Expression of the hpkA gene was low under vegetative conditions, but was highly induced under developmental conditions.

• 한국대기환경학회지
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• 제27권6호
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• pp.641-649
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• 2011

The aim of this study is to understand the characteristics of exhausting particulate matters (PM) and to control emitted PM from meat cooking restaurants. We found that $PM_{2.5}$, $PM_{5.0}$ occupy 69.2% and 98.6% of total PM from pork cooking, respectively. Therefore, we can see that it is not easy to remove PM generated from a pork cooking process. The collection efficiencies of various control devices, which are a condensing scrubber, a cyclone, an impactor, an oil filter and an electrostatic precipitator (ESP), were measured and compared. ESP had the highest collection efficiency (88.6%) and condensing scrubber had the lowest one (68.0%). However, the system recovering property should be considered to choose a control device because PM from meat cooking process are extremely stickiness. Therefore, we can recommend that ESP following an impactor or a cyclone is the best combination to remove PM generated from meat cooking restaurants.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.3-8
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• 2009

Since 2001, the Building Energy Efficiency Rating and Certification System have been implemented in Korea. For rating the energy efficiency performance, the evaluation tool for Building Energy Efficiency Rating System has been used. In this study, the evaluation tool was compared with detailed analysis programs(Trnsys 16, ESP-r) through simulations of heating energy needs for apartment, and we checked the character of the evaluation tool.

• International Journal of Automotive Technology
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• 제7권2호
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• pp.201-208
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• 2006

This paper describes the control philosophy of ESP(Electronic Stability Program) which consists of the stability control the fault diagnosis and the fault tolerant control. Besides the functional performance of the stability control, robustness of control and fault diagnosis is focused to avoid the unnecessary activation of the controller. The look-up tables are mentioned to have the accurate target yaw rate of the vehicle and obtained from vehicle tests for the whole operation range of the steering wheel angle and the vehicle speed. The wheel slip control with a design goal of wheel slip invariance is implemented for the yaw compensation and the target wheel slip is determined by difference between the target yaw rate and actual yaw rate. Since the ESP has a high severity level and the robust control is required, the robustness margin for the stability control is determined according to several uncertainties and the robust fault diagnosis is performed. Both computer simulation and test results are shown in this paper.

• 한국토양비료학회지
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• 제33권2호
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• pp.92-99
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• 2000

음식물쓰레기 퇴비 시용이 논 토양과 밭 토양의 Na집적에 미치는 영향을 비교하고자 실내 항온 실험을 하였다. 음식물쓰레기 혼합비율을 달리하여 부숙시킨 6종의 음식물쓰레기 퇴비를 처리하여, 논 토양은 담수조건으로, 밭 토양은 포장용수량 상태로 $25^{\circ}C$에서 항온시켰다. 음식물쓰레기 혼합비율이 높은 퇴비일수록 Na 함량과 EC가 높았다. 음식물쓰레기 퇴비의 양이온 무기화 율은 논과 밭 토양 간에 차이가 없었으며, Na, K, Mg 및 Ca가 각각 99, 94, 71 및 55%로서 Na>K>Mg>Ca 순으로 높았다. NaCl 함량이 높은 퇴비를 시용할수록 논과 밭 토양에서 공히 SAR과 ESP가 고도의 유의성 ($R^2=0.99$)을 가지고 직선적으로 증가하였다. SAR과 ESP 증가율은 논 토양에 비해 밭 토양에서 2.3배 높았다. 이 차이는 SAR분석 시 실제 상황을 감안하여 논 토양은 담수 상태의 토양용액을 사용하였던 반면, 밭 토양은 포화추출용액을 사용하므로써, 토양:물 비가 크게 달라서 일어나는 회석효과 때문으로 판단되었다. SAR 계산 시 분모로 사용되는 논 토양의 $([Ca^{2+}+Mg^{2+}]/2)^{1/2}$은 음식물쓰레기 퇴비 처리들 간에 2.1~2.4로 별 차이가 없었 던 반면, 분자로 사용되는 [$Na^+$]는 3.1~9.5로 편차가 컸다. 따라서 토양 Na집적을 고려한 음식물쓰레기 퇴비 품질 평가 시, Ca와 Mg 함량을 무시하고 Na 함량 만 사용할 것을 제안하였다. 토양 Ex. Na함량은 ESP와 고도의 유의성이 있는 직선관계를 보여, 새로운 토양 Na 집적 지표로 토 Ex. Na 함량을 제안하였다.

• 대한지리학회지
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• 제40권6호
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• pp.671-693
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• 2005

이 논문은 현대 사회의 이데올로기적 바탕을 이루고 있는 자유주의적 이론에서 제시되거나 또는 함의된 환경론을 고찰하고, 특히 환경정의의 관점에서 이를 비판하고자 한다. 우선 포괄적 의미에서 자유주의적 견해에서 이해되는 환경론을 살펴보고, 다음으로 보다 심층적으로 로크 등의 근대 사상가로부터 시작되는 고전적 자유주의와 여기서 분화된 자유지상주의, 공리주의를 환경론적 관점에서 해석하고자 한다. 끝으로 자유주의에 근거한 다원주의 및 이에 대한 비판으로 제기되고 있는 다양한 대안적 다원주의들, 특히 공동체주의, 포스트모던 다원주의, 그리고 문화적 다원주의 등을 자유주의의 한계 극복과 환경(정의)론의 구축과 관련하여 고찰하고자 한다. 결론적으로 환경정의에 관한 바람직한 개념화와 환경문제에 대한 올바른 접근을 위하여 최소한 자유주의(자유주의적 다원주의를 포함)에서 비판적 다원주의로 관심을 전환해야 함을 주장하고자 한다.

• 한국입자에어로졸학회지
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• 제9권2호
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• pp.103-110
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• 2013

The electrostatic precipitator (ESP) has been used for degrading atmospheric pollutants. These devices induce the electrical forces to facilitate the removal of particulate pollutants. The ions travel from the high voltage electrode to the grounded electrode by Coulomb force induced by the electric field when a high voltage is applied between two electrodes. The ions collide with gas molecules and exchange momentum with each other thus inducing fluid motion, electrohydrodynamic (EHD) flow. In this study, for the simulation of electric field and EHD flow in ESPs, an open source EHD solver, "espFoam", has been developed using open source CFD toolbox, OpenFOAM(R) (Open Field Operation and Manipulation). The electric potential distribution and ionic space charge density distribution were obtained with the developed solver, and validated with experimental results in the literature. The comparison results showed good agreement. Turbulence model is also incorporated to simulate turbulent flow; hence the developed solver can analyze laminar and turbulent flow. In distributions of electric potential and space charge, the distributions become distorted and asymmetric as the flow velocity increases. The effect of electrical drift flow was investigated for different flow velocities and the secondary flow in a flow of low velocity is successfully predicted.