• 제목/요약/키워드: balance law

검색결과 201건 처리시간 0.031초

열분해 가스화 용융시스템에서 용융슬래그의 폐열 활용 (Waste Heat Utilization of Melted slags at Pyrolysis, Gasification and Melting System)

  • 이호석;성상철;오명도
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2008년도 하계학술발표대회 논문집
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    • pp.1237-1242
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    • 2008
  • A study on waste heat utilization of melted slags at pyorlysis, gasification and melting system was performed. Researchers studied heat balance of substances that flow and flow out to the system which is consisted of melting furnace, combustion chamber, and waste heat boiler, then they calculated melting slags' quantity of heat by the first law of thermodynamics. If they use water cursh pit outflow which is gotten by quenching of melting slag as a energy for heating and cooling system, steam of waste heat boiler would be delivered to a steam turbine, making energy, then they will get 67,671,000 won of profit a year. It will take 3 years to repossess the cost that they invested for building it. And, if we predict durability of trash burner is 20 years, we will get approximately 1,150,407,000 won of profits in 17 years without the period when we repossess the building costs.

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상류유동전개부, 수축부 및 자유분사류로 이어지는 유동장에서의 난류에너지 천이에 대한 연구 (Transition of Turbulent Kinetic Energy Through a Serial Unit of Straight-Duct, Contraction and Free-Jet)

  • 한용운;남경덕
    • 대한기계학회논문집
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    • 제16권12호
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    • pp.2368-2375
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    • 1992
  • 본 연구에서는 축대칭 유동장치를 구성하여 열선 풍속계를 이용, 중심축에 따 른 난류쇠퇴양식을 살펴보고 동시에 난류에너지천이에 대한 세밀한 분석을 통하여 각 각 상류유동전개부, 수축부 및 자유분사류로 연속되는 3개의 유동 구조속에서 어떻게 천이해 갈 것인가를 측정하여 축대칭 유동의 난류구조 변천에 대한 기초 실험자료로 제시하고저 한다.

Modified DEBA for determining size dependent shear fracture energy of laminates

  • Goodarzi, M. Saeed;Hosseini-Toudeshky, Hossein
    • Steel and Composite Structures
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    • 제28권1호
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    • pp.111-121
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    • 2018
  • It has been argued that fracture energy of composite laminates depends on their thickness and number of layers. In this paper a modified direct energy balance approach (DEBA) has been developed to evaluate the mode-II shear fracture energy for E-glass/Epoxy laminates from finite element model at an arbitrary thickness. This approach considers friction and damage/plasticity deformations using cohesive zone modeling (CZM) and nonlinear finite element modeling. The presence of compressive stress and resulting friction was argued to be a possible cause for the thickness dependency of fracture energy. In the finite element modeling, CZM formulation has been developed with bilinear cohesive constitutive law combined with friction consideration. Also ply element have been developed with shear plastic damage model. Modified direct energy balance approach has been proposed for estimation of mode-II shear fracture energy. Experiments were performed on laminates of glass epoxy specimens for characterization of material parameters and determination of mode-II fracture energies for different thicknesses. Effect of laminate thickness on fracture energy of transverse crack tension (TCT) and end notched flexure (ENF) specimens has been numerically studied and comparison with experimental results has been made. It is shown that the developed numerical approach is capable of estimating increase in fracture energy due to size effect.

연속이온교환평형 칼럼 모델 개발 (Development of Column ion Exchange Modeling with Successive Ion Exchange Equilibrium)

  • 이인형
    • 한국산학기술학회논문지
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    • 제3권2호
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    • pp.141-145
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    • 2002
  • 이온교환수지탑으로 유입된 이온은 연속적인 이온교환 평형을 이루면서 수지층을 통과한다는 가정하에 질량작용법칙과 몰 균형식을 조합하여 연속이은교환평형 칼럼모델을 개발하였다. 연속이온교환평형 칼럼모델을 이용하여 원자력발전소 복수탈염설비 탈염기의 성능을 평가한 결과, Na/sup +/및 Cl/sup -/누출 농도는 수지의 재생효율에 따라 다르며, 특정이온의 유입수 및 유출수에서 농도 비율은 용액 및 수지의 상태에 따라 달라짐을 확인하였다. 본 모델은 수지농도를 보정하여 국부 불완전 평형을 고려할 수 있고, 다성분 존재하의 경쟁적 이온교환을 묘사할 수 있는 장점을 가지고 있다.

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Airborne Remote Sensing of Evapotranspiration over Rice Paddy

  • Chen, Y.Y.;Liou, Yuei-An
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.351-353
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    • 2003
  • We present a retrieval scheme for the remote sensing of evapotranspiration (ET) over rice paddy. To perform the retrieval, high-resolution airborne imagery of multi-spectral visible and thermal infrared data, and ground-based meteorological measurements are utilized. Our ET retrieval scheme is based on the basic principal of surface energy budget, which is a result of balance in longwave and shortwave radiation, latent heat, sensible heat, and energy flux into the ground. To partition the latent and sensible heat fluxes of interest from the energy balance equation, three basic parameters are of most concern, including albedo, surface temperature, and normalized difference vegetation index (NDVI). The NDVI and albedo can be easily derived from the visible and near infrared spectral data, while the surface tem-perature can be determined through the analysis of the infrared data with the Stefan Boltzmann law. From the airborne imagery taken on 28 April 2003, we observe very good dry and wet pixels that can be easily corre-sponded to the radiation and evaporation controlled crite-ria, respectively, and, hence, for the further use in defin-ing the evaporative fraction needed to partition sensible and latent heat fluxes from the net energy flux. The de-rived ET is compared with the in situ measurements.

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우리나라 여대생의 배우자 선택 및 결혼관에 관한 조사연구 (A Study on the View of Choice of Spouse and Marriage of Unmarried Women's College Students)

  • 김영옥
    • 한국생활과학회지
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    • 제8권1호
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    • pp.29-43
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    • 1999
  • This study was carried out to investigate the view of the choice of spouse and marriage of unmarried women's college students. Most respondents in this study think that the optimum age for marriage is 27 and prefer a seniority in age of 3-4 years who feels in love as the future husband. Also, they wish that the job of future husband be a technical expert. Approximately 63% of respondents recognize the necessity of marriage but 38% of respondents do not show a positive opinion for marriage. They also expect the emotional stabilization or partnership from marriage. Majority of respondents show a negative response to the marriage as means to solve economic difficulties. However, only 25.9% of respondents strongly show the negative opinion. In the acquaintance of the opposite sex in the purpose for marriage, most respondent are negative. However, they are positive in keeping virginal purity prior to marriage. Also, it has revealed that respondents want a partnership through allotment in domestic duties including baby sitting rather than household management through patriarchal system. In household economy, they prefer sharing living expenses and having a job after marriage. In choosing an ideal husband, although the academic background is considered as an important factor, but the present occupation is more important than the academic background. Also, one of the priority to choosing a spouse is influenced by each household circumstance and economic balance. About half of respondents want their parents-in-law to be alive, however, few respondents want to live together with parents-in-law.

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페미니스트 현상학을 이용한 한국 유방암 환자의 질병체험 (Illness Experience of Women with Breast cancer in Korea: Using Feminist Phenomenology)

  • 박은영;이명선
    • 성인간호학회지
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    • 제21권5호
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    • pp.504-518
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    • 2009
  • Purpose: The purpose is to explore the illness experience of Korean women with breast cancer using feminist phenomenology. Methods: Data were collected by individual in-depth interviews from ten women with total mastectomy. The data were analyzed using Colaizzi's method from feminist perspective to reveal implicit socio-cultural norms that oppress women with breast cancer. Results: Two categories and seven major themes emerged: cancer-related experience (1) unfairness of having breast cancer; (2) being confined to the gaze of the others; patriarchy-related experience (3) hardness of being daughter-in-law; (4) struggling to keep on being good mother; (5) continued housework as duty; (6) recognizing self as precious wife, and (7) awakening of true self. All participants felt it was very unfair to get breast cancer because they had done their best for roles of mother, wife, and daughter-in-law. They struggled to free themselves from the social disgrace like the roles imposed by the patriarchal society. By awakening their true selves, they could manage a balance between other-oriented life and self-oriented life. Conclusion: Oncology nurses need to provide psychosocial support for women with breast cancer in finding their true selves in a traditional patriarchal society where women are oppressed and breast cancer is stigmatized.

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미세기포 발생 펌프에서 생성되는 기포농도와 용존공기농도의 비교 (Comparison of Dissolved Air and Micro-Bubble Concentration by a Micro-Bubble Generating Pump)

  • 이창한;안갑환
    • 한국환경과학회지
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    • 제23권11호
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    • pp.1835-1842
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    • 2014
  • The goal of this study was to evaluate micro-bubble concentration ($C_{air}$) in water by air/water ratio (A/W ratio) with a micro-bubble generating pump. The estimation of micro-bubble concentration is based on the balance of inlet/outlet air and water flow rate. On net A/W ratio to be generated micro-bubble, we found that the obtained the $C_{air}$ are shown as a function of discharge pressure ($P_g$) of the micro-bubble generating pump. The correlation of the $C_{air}$ and the $P_g$ ($C_{air}=3.261P_g-1.754$) was adequately described by the least square methods with a high correlation coefficient (r = 0.9459) and calculated values fit the experimental data quite well. The $C_{air}$ was lower than theoretical dissolved air concentration ($C_{aq}$) calculated by Henry's law. The $C_{air}$ for being operated the micro-bubble generating pump was 6.75 - 39.53 mL/L, however, we found that the optimum of the $C_{air}$ to generate micro-bubble was the range from 10 to 12 mL/L.

한.일 FTA체결에 따른 수산부문 영향 분석 (The Effect Analysis of Korea-Japan FTA on Fisheries Sector)

  • 이광남;박명섭
    • 무역상무연구
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    • 제22권
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    • pp.227-254
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    • 2004
  • This paper focuses on the analysis of effects on fisheries sector following Korea-Japan Free Trade Agreement and the results are found as follows. In terms of national competitiveness, the RCA(Revealed comparative advantage) index shows that Korea is higher than Japan in most species items. And the calculation of TSI(Trade Specialization Index) finds that Korea is export specialized while Japan import specialized, showing that Korean fisheries sector is internationally more competitive than Japan. The tariffs on the marine products should be completely scrapped between Korea and Japan, export of marine products to Japan increases a mere 2%, while import from Japan 13.5%. In terms of value, annual export to Japan stands at 20,135thousand USD, while import from Japan at 12,137thousands USD, resulting in trade balance improvement of 8,000thousand USD in total. The tariff measures above is expected to have a positive effect on the related industry of marine products such as Oyster, Conger eel, Ark shells and Laver, but those involved in fisheries of Alaska pollack, Hair tail, Sea-bream(live fish), Red horsehead(frozen), Saury are expected to be negatively affected. Given the results of analysis above, the effects of FTA on the fisheries would be advantageous to Korea as a whole, but at the same time, the advantage and disadvantage sustained differs by fishery type and marine products. To that effect, negotiation strategies and countermeasures should be made, taking the results into account.

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선화주 균형발전을 위한 해운법 및 독점규제법의 개정방향에 관한 연구 (A Study on the Direction for Revision of Korea Shipping Act and Monopoly Regulation and Fair Trade Act)

  • 박광서
    • 무역상무연구
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    • 제49권
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    • pp.213-236
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    • 2011
  • Korea Shipping Act admits shipping conferences' joint actions like rate agreement, sailing agreement in some degree for development of shipping transport industries for decades. Meanwhile, EU has prohibited all kinds of shipping conferences' joint actions since October 2008, and many advanced countries also have similar position on shipping conference. The balance development between shippers and ship owners is very important in terms of national economic growth. So it is appropriate time to revise related laws such as Shipping Act and Monopoly Regulation and Fair Trade Act. First, It is direction for revision of Korean Shipping Act. The act has to define precisely the criteria of "unfairness" in case of admitting of shipping conferences' joint actions. Shipping conferences have a conference with shipper or shipper's delegation substantially on freight and transport conditions and so on. Second, It is direction for revision of Monopoly Regulation and Fair Trade Act. The fair trade commission has to perform fair roles between shippers and ship owners. The judgement of fairness has to confirm according to the spirit of not Korea Shipping Act but Korea Monopoly Regulation and Fair Trade Act itself.

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