• 제목/요약/키워드: specific discharge

검색결과 608건 처리시간 0.032초

Line Start 형 리니어 압축기 (Line Start Linear Compressor without Stroke Controller)

  • 홍언표;박경배;최기철;이형국
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2004년도 유체기계 연구개발 발표회 논문집
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    • pp.697-702
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    • 2004
  • LG Electronics developed linear compressors for a household refrigerator which can reduce energy consumption up to $24\%$ by only Drop-ln instead of a conventional reciprocating compressor. The linear compressor is composed of a linear oscillating motor, a piston directly coupled with the linear motor, a cylinder and the specific discharge system of LG. Because of this free-piston structure, the position of the piston can be changeable according to the voltage variation, load variation and so on. By this reason, LG linear compressor has been in need of an additional unit to control the position of the free-piston stably. In this paper we will introduce the innovative technology which is able to operate the linear compressor without controlling the piston position like a conventional reciprocating compressor.

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열역학법에 의한 펌프의 수력효율측정 (Efficiency measuring in pump using Thermodynamic method)

  • 권영준;서창덕;정용채;박장원
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2004년도 유체기계 연구개발 발표회 논문집
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    • pp.546-551
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    • 2004
  • An applying Thermodynamic method for the purpose of measuring hydraulic efficiency of pump-motor system, based on IEC60041 code, is not easy to adopt at field test. Even though there were splendid development in measuring technic in discharge measuring through the hydraulic machina lots of unsolved problems concerned in flow-rate are still remain in measuring hydraulic efficiency in hydraulic machine. The key point in measuring hydraulic efficiency is to measure exact flow-rate. So, Thermodynamic methode provides a good solution. This methode measures hydraulic efficiency by detecting the difference of temperature and pressure between the hydraulic process of machine, without measuring flow-rate of pump or turbine. By measuring temperature in mk level and absolute pressure in pascal, we can get a difference of thermodynamic specific energy in Moliere chart before and after of hydraulic process, md that difference is equal to hydraulic loses. Following the standard in proceeding Thermodynamic methode, I hope these trial and records make others be familiar to the thermal methode and make it easer to beginner for trial.

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Monoclonal antibody-based enzyme immuno-slide assay (EISA) in the rapid diagnosis of Peste des petits ruminants of goats

  • Das, Kamol K.;Rahman, M.B.;Shil, N.K.;Rahman, Md Siddiqur;Jang, Hyung-Kwan;Song, Hee-Jong
    • 한국동물위생학회지
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    • 제33권1호
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    • pp.1-6
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    • 2010
  • Monoclonal antibody (mAb)-based enzyme immune-slide assay (EISA) was used for the detection of Peste des petits ruminants (PPR) virus from field samples collected from a natural outbreak. The clinicopathological study was undertaken to diagnose the case primarily of PPR. Antigen was detected from discharges and faeces of infected goats and swabs of postmortem lesions prepared on glass slide or glass plate using acetone fixation. Nasal discharge collected at the early stage of disease course or lung is an appropriate ante- or postmortem sample for this technique, respectively. Convalescent polyclonal sera collected from recovered animals which were diagnosed as PPR by EISA showed high antibody titer against PPR by C-ELISA, demonstrating the satisfactory specificity of the test. Therefore, EISA is a sensitive and specific assay to confirm PPR infection both in field and laboratory conditions and especially suitable for developing country.

점토-Fly Ash 혼합물로 된 제체의 사면안정 해석(지반공학) (The Analysis of Slope Stability on Clay-Fly Ash Mixtures Embankment)

  • 권무남;정성욱;김현기
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2000년도 학술발표회 발표논문집
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    • pp.477-483
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    • 2000
  • Fly ash is the unburned residue resulting from the combustion of coal in utility and industrial boilers such as thermal power plants. Annually about 5 million tons of fly ash is being produced in korea. Less than 25 percent of total volume of fly ash is currently being used effectively for some ways. In the future, the volume of fly ash discharge from thermal power stations will be increasing more and more, and the development of the utilization of high volume fly ash is required. Fly ash has a lower compacted density and specific gravity than coarse grained natural aggregates but equivalent strength properties indicating that the fly ash could be used as a structural fill materials. So, clay-fly ash mixtures can be used as a fill material in the construction of embankments. Laboratory tests have been carried out to determine the physical, chemical, and geotechnical characteristics of the clay and fly ash. The fly ash is mixed with the clay in different proportions and the geotechnical characteristics of the mixtures have been studied also. In this study describes the results of the experimental study. The implications of the use of clay and clay-fly ash mixtures on the stability of embankments are discussed.

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중소유역의 수문학적 특성이 하천유사량에 미치는 영향 (The Effects of Hydrologic Characteristics on Sediment Discharge in Streams with Small and Medium Size Watersheds)

  • 김활곤;서승덕
    • 한국농공학회지
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    • 제38권3호
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    • pp.127-136
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    • 1996
  • The purpose of this study is to provide with information for the water resources development and management in stream management planning, such as information on the sediment trensport, design of dam and water facilities, river improvement and flood plains management. The major results obtained from the field measurement and analysis of the watershed characteristics, hydraulic and sediment characteristics are as follows ; 1. The rating curve formulas obtained from the analysis of the hydraulic characteristics data collected are ; Q-=110.563 $(H-0.474)^2$ for 0.7m$(H-0.146)^2$ for 0.4m$Sr=aX{^2} {_1} X^{c}{_2}$, in the experimental watershed.

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Light Tar Decomposition of Product Pyrolysis Gas from Sewage Sludge in a Gliding Arc Plasma Reformer

  • Lim, Mun-Sup;Chun, Young-Nam
    • Environmental Engineering Research
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    • 제17권2호
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    • pp.89-94
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    • 2012
  • Pyrolysis/gasification technology utilizes an energy conversion technique from various waste resources, such as biomass, solid waste, sewage sludge, and etc. to generating a syngas (synthesis gas). However, one of the major problems for the pyrolysis gasification is the presence of tar in the product gas. The tar produced might cause damages and operating problems on the facility. In this study, a gliding arc plasma reformer was developed to solve the previously acknowledged issues. An experiment was conducted using surrogate benzene and naphthalene, which are generated during the pyrolysis and/or gasification, as the representative tar substance. To identify the characteristics of the influential parameters of tar decomposition, tests were performed on the steam feed amount (steam/carbon ratio), input discharge power (specific energy input, SEI), total feed gas amount and the input tar concentration. In benzene, the optimal operating conditions of the gliding arc plasma 2 in steam to carbon (S/C) ratio, 0.98 $kWh/m^3$ in SEI, 14 L/min in total gas feed rate and 3.6% in benzene concentration. In naphthalene, 2.5 in S/C ratio, 1 $kWh/m^3$ in SEI, 18.4 L/min in total gas feed rate and 1% in naphthalene concentration. The benzene decomposition efficiency was 95%, and the energy efficiency was 120 g/kWh. The naphthalene decomposition efficiency was 79%, and the energy yield was 68 g/kWh.

The Synthesis of Na0.6Li0.6[Mn0.72Ni0.18Co0.10]O2 and its Electrochemical Performance as Cathode Materials for Li ion Batteries

  • Choi, Mansoo;Jo, In-Ho;Lee, Sang-Hun;Jung, Yang-Il;Moon, Jei-Kwon;Choi, Wang-Kyu
    • Journal of Electrochemical Science and Technology
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    • 제7권4호
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    • pp.245-250
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    • 2016
  • The layered $Na_{0.6}Li_{0.6}[Mn_{0.72}Ni_{0.18}Co_{0.10}]O_2$ composite with well crystalized and high specific capacity is prepared by molten-salt method and using the substitution of Na for Li-ion battery. The effects of annealing temperature, time, Na contents, and electrochemical performance are investigated. In XRD analysis, the substitution of Na-ion resulted in the P2-$Na_{2/3}MO_2$ structure ($Na_{0.70}MO_{2.05}$), which co-exists in the $Na_{0.6}Li_{0.6}[Mn_{0.72}Ni_{0.18}Co_{0.10}]O_2$ composites. The discharge capacities of cathode materials exhibited $284mAhg^{-1}$ with higher initial coulombic efficiency.

신경망을 이용한 보이드 결함에 의한 열화진단 (Degradation Diagnosis by Void Defects Using a Neural Network)

  • 최재관;김성홍;김재환
    • 한국전기전자재료학회논문지
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    • 제11권10호
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    • pp.940-945
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    • 1998
  • In this paper, we obtained the data, which is required in training the neural network and diagnosing the degradation degree, by introducing the AE detection that is effective method in ordinary degradation diagnosis on activation. Aa the results of generalization tests by appling neural network to the unknown AE patterns obtained from two kinds of specimen, firstly as to evaluate an objective performance of neural network, the recognition ration for no-void specimen and 1[mm] -void specimen are appeared to be 98.9% and 92.5%, respectively. Also, in the evaluation of the adaptability of neural network with a new type of 0.2[mm] -void specimen, it is confirmed that the result appears to be 64% of recognition ratio at 94% of confidence interval coefficient in expectation output 0.2. On the other hand, the recognition capability of the neural network was confirmed by data from no-void and 1[mm] void specimen. The results prove the promising possibility of the application of ANN to discriminate specific void affecting as main degradation source at partial discharge condition in insulator containing multi-void by accummulated data base.

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새로운 합성법에 의한 LiV$_3$O$_8$ 의 초음파처리 특성 (The Ultrasonic Treatment Characteristics of LiV$_3$O$_8$ by New Synthesis)

  • 박수길;김종진;손원근;김상욱;류부형;이주성
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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    • pp.151-154
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    • 1998
  • The layered trivanadate, LiV$_3$O$_{8}$ has been investigated as a cathode material for secondary lithium batteries. Early in its development the preparation method of LiV$_3$O$_{8}$ strongly influenced its electrochemical properties, such as discharge capacity, rate capability and cycling efficiency. In the present experiment, a new synthesis route has been applied to obtain LiV$_3$O$_{8}$ . Instead of the conventional high temperature technique leading to the crystalline form, a solution technique producing the amorphous form has been used. This material, after dehydration, shows an electrochemical performance exeeding that of the crystalline one. The rationale for this behavior mainly lies in microscopic factors, i.e., in the possibility for the unit cell of amorphous LiV$_3$O$_{8}$ to insert up to 9 Li$^{+}$, instead of six for crystalline LiV$_3$O$_{8}$ . The ultrasonically treated products in water were characterized by XRD, TGA, DSC, and SEM. These measurements showed that the ultrasonic treatment process of crystalline LiV$_3$O$_{8}$ causes a decrease in crystallinity and considerable increases in specific surface area and interlayer spacing.g.

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근거기반 임상실무지침: 장루간호 (Evidence-Based Nursing Practice Guideline: Ostomy Care)

  • 이윤진;박현숙;김민경;서희원;이미주;원은애;조가나
    • 임상간호연구
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    • 제26권2호
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    • pp.154-163
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    • 2020
  • Purpose: The aim of this study was to develop an evidence-based guideline for stoma management providing institutional policy, assessment, complications and follow-up care. Methods: The guideline adaptation manual consisting of 23 steps developed by the National Evidence-Based Healthcare Collaborating Agency was used for this study. It presents an overview of the process used to develop the guideline and lists specific recommendations from the guideline. Results: It provides 55 recommendations that include the following 8 topics: 1) Organization and policy recommendations, 2) Preoperative nursing; Ostomy education, stoma site marking, 3) Ostomy formation, 4) Postpoperative nursing; education, assessment, high output stoma management, 5) Selection of ostomy products, 6) Colostomy irrigation, 7) Stomal and peristomal complications, 8) Follow-up care after discharge. Conclusion: The guideline can be used to address stoma management in hospital settings. The intent of the guideline is to provide information that will assist healthcare providers to manage adult patients with ostomies, prevent or decrease complications, and improve patients' outcomes.