• 제목/요약/키워드: Efficiencies

검색결과 3,649건 처리시간 0.03초

A Study on the Marking Efficiency of Tailored Jacket (테일러드 재킷의 Marking 효율성에 관한 연구)

  • Lee, Mi-Sook;Uh, Mi-Kyung;Suh, Mi-A
    • The Research Journal of the Costume Culture
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    • 제14권2호
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    • pp.310-319
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    • 2006
  • This study intended to compare and analyze marking efficiencies of tailored jacket based on different cloth and production conditions, 'the width of cloth', 'the number of marking pieces' and 'the direction for marking deployment'. The results were as follows. For the two pieces of markers, the efficiency of the cloth width of 110cm was higher than that of 150cm. As the number of markers increased, the efficiency of cloth width of 150cm was higher than that of 110cm. In the case of one-directional deployment, the results obtained was that the efficiency of two markers was higher than that of three markers, while, in the case of bi-directional deployment, the efficiency of three markers was higher than that of two markers. In the case of one-directional deployment for each size, the marking efficiencies were higher in two markers at the cloth width of 110 cm and higher in three markers at the cloth width of 150 cm. Then, in marking efficiencies according to the direction for marking deployment, bi-direction marker was the most efficient marker, followed by one-direction for each size marker and one-direction marker.

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Treatment of Phosphorus Species using Iron Coagulation and Fenton Oxidation (철염 응집과 펜톤 산화를 이용한 인의 존재형태별 처리)

  • Park, Sung-Hwan;Moon, Byung-Hyun
    • Journal of Korean Society on Water Environment
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    • 제30권6호
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    • pp.653-657
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    • 2014
  • Effects of $H_2O_2$ addition for fenton oxidation on iron coagulation for treatment of phosphorus species, such as orthophosphate, metaphosphate, pyrophosphate, organic phosphate, were investigated. The effects of coagulant dosage, hydrogen peroxide dosage and the combined sequence ferric coagulation and $H_2O_2$ addition for fenton oxidation and coagulation were studied. The characteristics of floc growth rate were monitored using the PDA. The removal efficiencies of phosphorus species by iron coagulation were increased as Fe/P molar ratio increased. However, the removal efficiencies of metaphosphate, pyrophosphate, organic phosphate by a ferric coagulation were not increased as Fe/P molar ratio increased. The removal efficiency of metaphosphate, pyrophosphate, organic phosphate was increased by using iron coagulation and $H_2O_2$ addition for fenton oxidation. The result indicated that non-reactive phosphorus after iron coagulation was changed to reactive phosphorus by $H_2O_2$ addition for fenton oxidation and the oxidized iron enhanced the coagulation efficiencies.

Removal of NO/SO2 by the low temperature plasmas and photocatalysts (저온 플라즈마와 광촉매에 의한 NO/SO2 제거)

  • Kim, Dong-Joo;Kim, Kyo-Seon
    • Journal of Industrial Technology
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    • 제26권A호
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    • pp.181-188
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    • 2006
  • In this study, we analyzed the effects of several process variables on the removal efficiencies of NO and $SO_2$ by the dielectric barrier discharge process combined with photocatalysts. The $TiO_2$ photocatalysts were coated onto the spherical-shaped glass beads as dielectric materials by the dip-coating method to analyze the effects of photodegradation reaction on the NO and $SO_2$ removal. As the voltage applied to the plasma reactor increases, or as the pulse frequency of applied voltage increases, the NO and $SO_2$ removal efficiencies increase. Also as the residence time increases, or as the initial concentration of NO decreases, the NO and $SO_2$ removal efficiencies increase. The higher the amount of $TiO_2$ particles coated onto the glass bead is, the larger the surface area of $TiO_2$ particles for the photodegradation reaction is and the NO and $SO_2$ are removed more quickly by the faster photodegradation reactions.

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A Study on Efficient Simple Water Supply System in Rural Areas (농촌지역의 효율적인 간이 상수처리에 관한 연구)

  • 이홍근;백남원;백도현
    • Journal of Environmental Health Sciences
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    • 제22권3호
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    • pp.103-115
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    • 1996
  • The purpose of this study was to establish acceptable criteria for the design of simple water treatment plant in rural areas. To develop efficient simple water treatment methods for rural areas, water quality in the study areas was investigated and rapid and slow filtrations in pilot-scale were tested under various conditions. The main results of this study are as follows. It was found that the water qualities of the study areas exceed the drinking water standards, which implies that some treatments are required in rural areas. Treatment efficiencies of both rapid sand and dual-media (sand and anthracite) filtration without pre-treatment such as flocculation and sedimentation are very low, which were turned out to be unadequate for the rural areas. Treatment efficiencies of both vertical and horizontal slow filtration without chlorination are very high for consumed $KMnO_4, NH_3-N, NO_3-N$, turbidity, and very low for coliform and bacteria. Treatment efficiencies of both vertical and horizontal slow filtration with chlorination are very high over the most pollutants. A slow filtration with chlorination is efficient for the rural areas. An adequate depth of sand layer is over 60 cm. A horizontal filtration is more economical than a vertical filtration. A horizontal filtration can be operated for a relatively long periods of time without sand washing or replacement because clogging is removed by simple back-washing.

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A Study on the Electrochemical Characteristics of Hydrogen Storage Alloy Electrodes for Secondary Batteries (축전지용 수소저장합금 전극의 전기화학적 특성에 관한 연구)

  • KIM, Chan-Jung;LEE, Jae-Myoung;CHOI, Byung-Jin;KIM, Dai-Ryong
    • Journal of Hydrogen and New Energy
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    • 제4권2호
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    • pp.29-40
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    • 1993
  • Intensive studies on the electrochemical characteristics of TiFe type alloy electrodes have been carried out to clarify the mechanism of electrochemical hydrogen absorption and desorption. It was found that electrochemical activation of the TiFe type alloys is difficult and that charge efficiencies are very low even after a decade of activation cycles. However, by the pretreatment of the powders such as gas activation and/or Ni chemical plating, charge efficiencies fairly increased, especially for the $TiFe_{0.8}Ni_{0.2}$ alloy. It was considered that difficulties to activation and lower charge efficies of the alloys are due to the presence of the passivation films, which prohibit inward diffusion of hydrogen and promote the combination of adsorbed hydrogen atom to gas bubbles during the electrochemical charge. In addition, lower diffusivity of hydrogen in the alloys may be played an important role lowering the charge efficiencies.

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Quantitative approach to analyze searching efficiencies varying degrees of imbalance in a binary search tree (수량적 접근 방법에 의한 이진 검색 트리 불균형도에 따른 검색 성능 비교 분석)

  • 김숙영
    • Journal of the Korea Computer Industry Society
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    • 제3권2호
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    • pp.235-242
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    • 2002
  • To minimize restructuring cost of a tree, experiments were conducted to collect quantitative information of searching efficiencies varying degrees of imbalance in a binary search tree. Degrees of tree imbalance were measured by a balance factor, an absolute value of height difference of left subtree and right subtree in a binary search tree. The average number of comparisons increased (p<0.01), and searching efficiency of O(n) was more appropriate rather than O(logn), as degrees of imbalance in a binary search tree deteriorated. However, there were no significant differences of searching efficiencies in height balanced trees and trees with subtrees to have height 3 less than the other (p>0.05). Therefore, the findings would be applicable to maintain searching efficiency of a software with a binary search tree.

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Evaluating the Operational Efficiencies of Local Universities Using DEA Approach (자료포락분석을 이용한 지역대학의 효율성분석)

  • Choi, Kyoung Ho;Ahn, Jeong Yong
    • The Korean Journal of Applied Statistics
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    • 제26권1호
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    • pp.49-58
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    • 2013
  • Data envelopment analysis is a relatively new data oriented approach to evaluate the performance of a set of peer entities called decision making units which convert multiple inputs into multiple outputs. It has been extensively applied in performance evaluation and benchmarking entities such as hospitals, universities, cities, courts, and business firms. This study provides the evaluating results of the operational efficiencies of local universities using a DEA approach. In addition, we explore the difference of the efficiency between regional flagship national universities and non-flagships.

Application of Hybrid Constructed Wetland System for Stream Water Quality Improvement (오염하천 수질개선을 위한 Hybrid형 인공습지의 적용)

  • Kim, Seung-jun;Choi, Yong-su;Bae, Woo-keun
    • Journal of Korean Society on Water Environment
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    • 제22권2호
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    • pp.209-214
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    • 2006
  • The purpose of this study is to improve the stream water quality by the experimental hybrid constructed wetland system. It consisted of the water layer, sand bed planted reeds, irises and roses, gravel bed, yellow-soil media bed and a flow shifter (FS) which can reverse top and bottom flow in the middle of the wetland. The organic compounds and nitrogen removal efficiencies varied with the seasons, namely temperature change. In summer, the mean efficiencies of COD and TN in the outflow from this wetland system were 63.4 and 48.0% and shown the highest, respectively, whereas, the suspended solids and phosphorus removal efficiencies seemed to be less affected by temperature. As a result of inspecting the decreasing trend of pollutants, nitrification-denitrification in the wetland was the major removal mechanism for nitrogen, the nitrogen reduction was especially enhanced by the application of a FS in the wetland, and phosphorus reduction was mainly occurred as a consequence of adsorption of the yellow-soil media.

Assessment of Water Management Efficiencies for Irrigation Pumping Stations in the Han River and Nakdong River Basins (한강 및 낙동강 유역의 양수장 지구 물관리효율 평가)

  • Kim, Hyeon-Jun;Kim, Chul-Gyum;kim, Sung
    • Magazine of the Korean Society of Agricultural Engineers
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    • 제45권1호
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    • pp.23-32
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    • 2003
  • The objective of this study is assessing water management efficiency using water withdrawals from rivers and water requirements for paddies. The water management efficiency was defined by the ratio of water requirements and water withdrawals. Water withdrawals were estimated using the operating times and pumping capacity of the pumping stations from 1992 to 1999 in the Han River and Nakdong River basins. Water requirements were estimated by adding the evapotranspiration of the crops and infiltrations in the irrigated area. Evapotranspiration from the paddies was calculated by the FAO modified Penman method with observed daily weather data. The monthly water management efficiency was analyzed for each pumping stations and the district offices of KARICO (Korea Agricultural and Rural Infrastructure Corporation). The efficiencies of 59 pumping stations in the Han River basin varied from 19% to 135%, and the average was 61%. The efficiencies of 146 pumping stations in the Nakdong River basin ranged from 17% to 190%, and the average was 72%. There were no good correlations between the water management efficiency and pump capacity or irrigated area, it showed that the water management efficiency was affected by the traditional water management practices rather than the scale of irrigation district.

The Improved Artificial Trap Baits (통발용 인공미끼의 개발)

  • 염말구
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • 제34권2호
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    • pp.185-190
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    • 1998
  • The aim of this study was to develop the artificial trap baits being able to replace the natural anchovy or sardine baits. The fishing trials for evaluating the fishing efficiencies of the artificial baits were conducted with commercial traps at coastal areas near Tongyoung, southern Korea. The preferable artificial baits which were made of minced anchovy, sardine, mackerel, or fish surplus products mixed with wheat flour into dry or wet pelleted or crumbled types, were showed some merits as the following. \circled1 Fishing efficiencies of the artificial baits were same or little higher level than that of the natural bait anchovy; \circled2 bait cost were same or little lower level; \circled3 dry artificial baits stocked in the room condition showed good fishing efficiencies; \circled4 making of artificial baits were very simple; \circled5 there were no harm to the fish and little pollution to the environment; \circled6 the releasing rate of attractants in the artificial or natural bait showed similar patterns. The artificial baits using the fish by-products which were vacuum freeze-drying extract of boiled anchovy or tunas extract, showed lower catches in the conger eel, Coner miriaster, but similar catches in the crabs, mainly Charybdis japonica, to the those of natural anchovy bait.

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