• Title/Summary/Keyword: 최적효율

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Treatability Study on the Remediation Groundwater Contaminated by TPH Cr6+ : Lab-Scale Experiment (TPH와 6가 크롬으로 오염된 지하수 처리를 위한 실내 실험)

  • Lee, Gyu-Beom;Chang, Yoon-Young
    • Journal of Environmental Impact Assessment
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    • v.28 no.3
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    • pp.332-345
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    • 2019
  • The purpose of the study is to evaluate the treatability of contaminated groundwater with TPH and (or) $Cr^{6+}$. Laboratory scale tests were performed for oil/water separation, dissolved air flotation (DAF), coagulation and precipitation, and filtration with sand and activated carbon respectively. Two times of oil/water separation tests for total 40 minutes of separation or separating time shows 90.2 % of TPH removal rate. In case of DAF test for high TPH sample, the TPH removal rates were not varied significantly by the variation of microbubble size. However, tests for low TPH samples show that TPH removal rate increases as microbubbles are smaller. When coagulant was added to sample for DAF test, TPH removal rate was increased 12.3 %. SS removal rate by DAF was 97.9 % at $16-40{\mu}m$ and it was increased as the size of microbubble is reduced. Tests for coagulation and precipitation were performed to evaluate the removal of $Cr^{6+}$ in groundwater. The increase of $FeSO_4$ dosage increased $Cr^{6+}$ removal rate in the coagulation and precipitation process. As the amount of activated carbon in the filter media increased TPH removal rate in the filtration process. SS removal rate by the filtration was 96.7 % similar to the results of DAF process tests. The filtration process treats TPH and SS. Best design parameters are determined as the size of sand is $425-850{\mu}m$ and the ratio of activated carbon and sand is 50:50.

The Economic Analysis of Underground Parking Lot Frames adopting 8-Bay Parking Modules (8-Bay 주차모듈을 적용한 아파트 지하주차장 구조의 경제성 분석)

  • Yu, Yongsin;Yoon, Bohyung;Kim, Minsu;Kim, Taewan;Lee, Chansik
    • Korean Journal of Construction Engineering and Management
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    • v.20 no.1
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    • pp.52-61
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    • 2019
  • On 30 June, 2017, the Ministry of Land, Infrastructure, and Transport announced the minimum size of parking section will be expanded in parking lots. The expansion of parking section could lead to increase in apartment prices because of increase in total area of the parking lots. It is necessary to adjust the column spacing and number in the parking lots and to apply the 8-Bay long-span parking module with good parking efficiency. According to the study, the construction cost of the 6-Bay module and 8-Bay module was almost the same. But The 8-Bay module was more economical than the 6-Bay module because of the reduction in total area of 8-Bay multi-moduel. The Result of construction cost of 8-Bay modules, Removal Deck-plate RC system was most economical. While the construction cost of PC system was higher due to increase in volume of the member, it would ensure sufficient economy by reducing the girder height to apply a pre-stress method. Also, the construction cost of hollow slab system was the highest. But it could be used as the underground parking lots for apartment, because it had the lowest cost per square meter. This Study has a academic significance by proving the applicability of the 8-Bay Module to underground parking lot of apartment. And it is expected that this study will be used as basic data to derive optimal construction method that applies 8-Bay Module.

Evaluation of Operational Options of Wastewater Treatment Using EQPS Models (EQPS 모델을 이용한 하수처리장 운전 평가)

  • Yoo, Hosik;Ahn, Seyoung
    • Journal of the Korean Society of Urban Environment
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    • v.18 no.4
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    • pp.401-408
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    • 2018
  • EQPS (Effluent Quality Prediction System, Dynamita, France) was applied to analyze the appropriateness of the design of a bioreactor in A sewage treatment plant. A sewage treatment plant was designed by setting the design concentration of the secondary clarifier effluent to total nitrogen and total phosphorus, 10 mg/L and 1.8 mg/L, respectively, in order to comply with the target water quality at the level of the hydrophilic water. The retention time of the 4-stage BNR reactor was 9.6 hours, which was 0.5 for the pre-anoxic tank, 1.0 for the anaerobic tank, 2.9 for the anoxic tank, and 5.2 hours for the aerobic tank. As a result of the modeling of the winter season, the retention time of the anaerobic tank was increased by 0.2 hours in order to satisfy the target water quality of the hydrophilic water level. The default coefficients of the one step nitrification denitrification model proposed by the software manufacturer were used to exclude distortion of the modeling results. Since the process modeling generally presents optimal conditions, the retention time of the 4-stage BNR should be increased to 9.8 hours considering the bioreactor margin. The accurate use of process modeling in the design stage of the sewage treatment plant is a way to ensure the stability of the treatment performance and efficiency after construction of the sewage treatment plant.

A Study on the Development of Sleep Monitoring Smart Wear based on Fiber Sensor for the Management of Sleep Apnea (수면 무호흡증 관리를 위한 섬유센서 기반의 슬립 모니터링 스마트 웨어 개발에 관한 연구)

  • Park, Jin-Hee;Kim, Joo-Yong
    • Science of Emotion and Sensibility
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    • v.22 no.1
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    • pp.89-100
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    • 2019
  • Sleep apnea, a medical condition associated with a variety of complications, is generally monitored by standard sleep polysomnography, which is expensive and uncomfortable. To overcome these limitations, this study proposes an unconstrained wearable monitoring system with stretch-fiber sensors that integrate with the wearer's clothing. The system allows patients to undergo examinations in a familiar environment while minimizing the occurrence of skin allergies caused by adhesive tools. As smart clothing for adult males with sleep apnea, long-sleeved T-shirts embedding fibrous sensors were developed, enabling real-time monitoring of the patients' breathing rate, oxygen saturation, and airflow as sleep apnea diagnostic indicators. The gauge factor was measured as 20.3 in sample 4. The maximum breathing intake, measured during three large breaths, was 2048 ml. the oxygen saturation was measured before and during breath-holding. The oxygen saturation change was 69.45%, showing a minimum measurable oxygen saturation of 70%. After washing the garment, the gauge factor reduced only to 18.0, confirming the durability of the proposed system. The wearable sleep apnea monitoring smart clothes are readily available in the home and can measure three indicators of sleep apnea: respiration rate, breathing flow and oxygen saturation.

Study of the Priority of Baby Boomer Policy: Emotional Psychology through Analytic Hierarchy (AHP 분석방법을 통한 감성심리 기반의 베이비부머 정책 우선순위 결정)

  • Kang, Ju-Ree;Lee, Chung-Real;Hwang, Du-Kyung
    • Science of Emotion and Sensibility
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    • v.22 no.1
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    • pp.77-88
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    • 2019
  • As the social interest of the Baby Boomer generation is increasing, this study derives implications for lifelong education policy through identification of the need and support for lifelong education among baby boomers lifelong learning, taking into account such aspects of quality of life as emotional psychology-based self-development and self-realization. To optimally explore support for lifelong learning for the baby-boomer generation, first-tier (top-level), sixth-tier (bottom-level), and five-other evaluation criteria were available. For the first layer, we examined whether potentiality or realizability was more desirable, and for the second layer, detailed criteria for realizability were set up, dividing them into financial, legal, and administrative feasibility. A study conducted by experts on the policy priority analysis of Baby Boomers showed that their support for lifelong learning places a greater priority on its feasibility (the more feasible alternative) than desire (the more desirable option). Among the six criteria, lifestyle activities had high priority, and the relative importance of the five assessment alternatives for lifetime learning activities was shown to be higher for employment skills education (0.377), civil participation education (0.181), lifestyle activities (0.200), and 'lifetime activities' (06.11). These results are meaningful: they can help shape and refine the needs of lifelong education, assess their relative importance, and prepare basic data for lifelong learning policies for baby boomers who are about to enter their old age.

An Efficient AP Channel Scanning Scheme for Real-time VoIP Streaming in Wireless LAN (WLAN 기반 실시간 VoIP Streaming을 위한 효율적 채널 스캐닝 기법)

  • Cheon, Young-Chang;Youn, Hee-Yong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.10a
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    • pp.595-598
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    • 2014
  • In order to provide the Mobile Stations operating in IEEE 802.11 Wireless LAN network with seamless handover, a comprehensive study on the functions of handover considering various networking environments and characteristics of Mobile Stations is required. Note that the channel scan process finding a new AP takes the major portion of handover time, and this is the most significant issue with seamless handover for real-time multimedia service in WLAN environment. In this paper the functions required to provide seamless handover in IEEE 802.11 WLAN network are identified, and a new scanning technique is proposed with which the Mobile Stations can selectively scan the channels to reduce the channel scan time in various network environments. Here each Mobile Station awares of the channels the neighbor APs are using by scanning them in advance according to the proposed technique. Afterwards, when handover is actually required, the optimal AP is decided quickly by scanning only the predetemined group of channels and order of scan without unnecessary scan of all the channels. In addition, proposes to enter the Scan Trigger Value and Handover Threshold Value in mobile phones in order to prevent the phenomenon can not handover.

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Efficient Information System Sizing Selection Using Cloud Computing Platform (클라우드 컴퓨팅 플랫폼을 이용한 효율적인 정보시스템 용량 산정 방법에 관한 연구)

  • Seong, Baek-min;Lee, Min-gyu;Sohn, Hyo-jung;Kim, Jong-bae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.10a
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    • pp.79-81
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    • 2014
  • Recently, It is built various information systems evolve IT skills. But When you build the information system, Difficult to determine whether the appropriate scale and problems that rely heavily on SI companies and professionals. To solve this problem, Korea Information Security Agency, etc., based on the primary objective was to develop H/W Capacity Equation formally to each system type. But the problems are to present H/W capacity equation by discussion of the expert group of suppliers and relatively long that it is difficult to formally apply in the situation now so it is no longer the limit. In this study, we proposes proper capacity planning techniques, which can guarantee the best performance compared to the budget invested. For this purpose, we derived the proper H/W capacity equation by regression analysis to gather performance metrics and cost of various cases by simulation of a virtual environment in the cloud. Through this study, when capacity planning, It is possible to reduce costs that It is possible to build an information system based on the digitized data and build information system in an environment that does not rely on the SI business or professional.

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Intrusion of the extruded maxillary central incisor using skeletal anchorage system and unilateral segmental intrusion arch (골성 고정원과 편측 분절호선을 이용한 정출된 상악 중절치의 압하 치료)

  • Kwon, Eun-Young;Baek, Young-Jae;Park, Soo-Byung;Kim, Seong-sik;Kim, Yong-il;Choi, Youn-kyung
    • Journal of Dental Rehabilitation and Applied Science
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    • v.35 no.3
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    • pp.180-190
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    • 2019
  • Patients who have a moderate periodontitis with pathologic tooth migration of maxillary incisors, it is necessary not only periodontal treatment for reduce periodontal inflammation, but also orthodontic treatment to teeth repositioning. For orthodontic treatment, it is necessary to apply less force and careful considerations of the center of resistance of the tooth and optimal force of tooth movement. At this time, the segmental arch applied only to the target teeth, is more effective and predictable, because applied force and direction can be controlled. In addition, to design the orthodontic appliance that can prevent the unwanted tooth movement that used as an anchorage is important. In recent years, various types of skeletal anchorage system have been used for preventing loss of the anchorage. We reported the patient who had extruded maxillary central incisor due to pathologic tooth migration, treated by a successful periodontal-orthodontic multidisciplinary treatment using an orthodontic appliance designed to apply less traumatic force and reduce an anchorage loss.

A Basic Analysis on the Operation of the Cultural Heritage Committee (부록 1. 문화재위원회의 역할에 관한 기초적 분석)

  • Kim, Hong-real
    • Korean Journal of Heritage: History & Science
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    • v.38
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    • pp.421-474
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    • 2005
  • The Cultural Heritage Committee is an advisory committee established under the Cultural Heritage Administration with the aim of carrying out examination and deliberation on preservation, management and use of cultural properties. The Cultural Heritage Administration is responsible for Korean cultural properties. It was found to produce and execute policies on cultural properties, which involves in-depth investigation and consultation of experts in the fields of cultural properties. In here the Cultural Heritage Committee plays an important role in policy-making on Korean cultural properties. Governmental committees in Korea are largely divided into consultation committees and administrative commissions. Consultation committees are subdivided into consultation, deliberation and legislative committees. The Korean government established the Bureau of Cultural Properties in October 1961, and enacted provisions (as a presidential decree) on March 27, 1962, by the Cultural Properties Act, January 10, 1962. The Cultural Heritage Committee was opened as a deliberation committee which covers the entirety of cultural properties, including designation and cancellation of cultural properties, on which currently 120 members serve in 9 subcommittees. The committee member hold two years membership. This analysis contains a frame and scheme of the committee, function and statue of the current operation and study on role of a deliberation committee.

A Study on the Thermal Flow Analysis for Heat Performance Improvement of a Wireless Power Charger (열 유동해석을 통한 무선충전기 발열 성능 향상에 관한 연구)

  • Kim, Pyeong-Jun;Park, Dong-Kyou
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.7
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    • pp.310-316
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    • 2019
  • In automotive application, customers are demanding high efficiency and various functions for convenience. The demand for these automotive applications is steadily increasing. In this study, it has been studied the analysis of heat flow to improve the PCB(printed circuit board) heating performance of WPC (wireless power charger) recently developed for convenience. The charging performance of the wireless charger has been reduced due to power dissipation and thermal resistance of PCB. Therefore, it has been proposed optimal PCB design, layout and position of electronic parts through the simulation of heat flow analysis and PCB design was analyzed and decided at each design stage. Then, the experimental test is performed to verify the consistency of the analysis results under actual environmental conditions. In this paper, The PCB modeling and heat flow simulation in transient response were performed using HyperLynx Thermal and FloTHERM. In addition, the measurement was performed using infrared thermal imaging camera and used to verify the analysis results. In the final comparison, the error between analysis and experiment was found to be less than 10 % and the heating performance of PCB was also improved.