• Journal of Applied and Pure Mathematics
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• 제6권3_4호
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• pp.155-165
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• 2024

Let R be a semi-prime ring. Let [δ₁, D₁] and [δ₂, D₂] be two generalized symmetric reverse biderivations of R with associated reverse biderivations D₁ and D₂. The main aim of the present paper is to establish conditions of orthogonality for symmetric reverse biderivations and symmetric generalized reverse biderivations in R.

• 산업경영시스템학회지
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• 제32권4호
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• pp.72-78
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• 2009

Reverse logistics is the process of planning and controlling the recovery flow of end of life products. Industry is increasingly being confronted with the need to solve several reverse logistics issues because of not only stringent environmental legislations but also economic reasons. Recently, thanks to the advent of emerging technologies, such as RFID, enhancing the productivity of reverse logistics operations has been highlighted. The application of RFID technology is going beyond forward logistics, which is the delivery of manufactured goods to consumers, and being expanded, though not frequently yet, to reverse logistics, which includes return, recovery, reuse, reproduction and disposal. However, it requires a deep insight for the research of reverse logistics and new environment. In this regard, we studied effectiveness by applying RFID middleware technology to reverse logistics.

• Journal of Pharmaceutical Investigation
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• 제35권5호
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• pp.333-336
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• 2005

The objective of this study was to investigate the stability of tetracycline HCl on encapsulation into and inside reverse micelles. To do so, tetracycline HCl was first mixed with cetyltrimethylammonium bromide, water and ethyl formate to make reverse micelles. The degradation kinetics of tetracycline HCl inside the reverse micelles was then assessed by scrutinizing its stability data. Under our experimental conditions, the reverse micelles formed spontaneously in absence of any mixing devices. During the preparation of the reverse micelles, however, considerable portions of tetracycline HCl underwent a chemical reaction (e.g., epimerization). For instance, $51.4{\pm}0.6%$ of an initial concentration of tetracycline HCl was transformed into a degradation product. Once dissolved inside the reverse micelles, the degradation of tetracycline HCl followed an exponential decay pattern. The plot of log{the degradation rate of tetracycline HCl} versus log{tetracycline HCl concentration} made it possible to determine the order of degradation reaction and rate constant. It was proven that the degradation of tetracycline HCl inside the reverse micelles followed a first order kinetics with a rate constant of 0.0027 $hour^{-1}$. Meriting further investigation might be formulation studies to stabilize tetracycline HCl on encapsulation into and inside the reverse micelles.

• 한국주거학회논문집
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• 제16권5호
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• pp.49-56
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• 2005

This study will focus on status and structure of Japanese public reverse mortgage that has been changed since 1980. Especially, on newly introduced long-term supporting system for living fund after 2003. Private housing construction companies studied preceding cases of real estate products with reverse mortgage theory and also induced learning point from the change of Japanese public reverse mortgage market. From this on the purpose of this study is suggesting a better plan for successful reverse mortgage introduction in Korea. The data and articles of Japanese reverse mortgage are used for this study, also reverse mortgage related data are collected from web-site and research reports from the inside and outside of the country. From the total postal survey in September, 2004, the system contents after Year 2003 are described here. As described above, reverse mortgage is a way to support public social pension system and expected to play an important role as an assisting method for stable housing and supporting living cost to the aged. Eventually, it is necessary to find a way for introducing a public reverse mortgage as a welfare system for low income people.

• 한국시뮬레이션학회논문지
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• 제15권2호
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• pp.13-21
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• 2006

환경적인 부분에 대한 관심이 증대되면서 기업은 제품을 생산하고 판매하는 것만으로는 기업 이윤을 확보하는 데 어려움을 겪고 있다. 이에 대한 대책으로 이미 사용된 후 수명을 다한 제품과 자원(used products and materials)의 재활용에 대해 주목하게 되었고, 자원의 재활용에 대한 제도는 OECD 국가에서는 이미 보편화되어 있다. 이러한 변화에 발맞추어 자동차 산업에서도 제품의 친환경적인 측면이 강조되고 여러 관련 법규가 제정됨에 따라 상당히 큰 파장을 불러일으키고 있다. 특히 EU는 2005년부터 단계적인 폐차처리 지침을 만들고 이를 지키지 못하는 차량의 경우 더 이상 유럽 지역에 수출을 할 수 없게 하였다. 이에 따라 자동차 업계에서는 자동차의 재활용 및 부품의 재사용에 대한 연구가 활발히 진행되고 있으며, 수명이 다한 제품에 대해 리사이클링(Recycling)과 재사용(Reusing) 하여 제조 기업에게 피드백 하는 닫힌 고리(Closed loop) 형태의 회수물류(Reverse Logistics) 체계를 구축해야 하는 실정이다. 따라서 본 연구에서는 자동차 산업에서의 부품의 재사용과 재활용에 대한 Reverse Logistics 효과를 분석할 수 있는 Closed Loop 방식의 시뮬레이션 모델을 만들고 이를 통해 기존의 Supply Chain과 Reverse Supply Chain을 비교해 봄으로써 Reverse logistics의 도입에 따른 효과를 분석하고, 폐차율을 고려한 자동차 산업의 Reverse logistics의 도입 효과에 대한 분석도 수행하고자 한다. 본 연구의 결과를 통해 자동차 업계의 국내외 역물류의 도입에 따른 효과분석과 국내 폐자동차 관련 정책결정에 필요한 자료가 될 것으로 사료된다.

• Archives of Reconstructive Microsurgery
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• 제10권1호
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• pp.55-59
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• 2001

The hand is a frequently affected area in high voltage electrical burn injury as an input or output sites. Therefore, early debridement and synchronous flap coverage are generally accepted as a primary treatment of several electrical burns complicated by exposure of tendons, neurovascular structures, and bones. So, in order to establish convenient, promising methods for the reconstruction of hand defects in electrical burn patients, we performed various reverse forearm flaps. From March 1997 to February 2000, we reconstructed 12 cases of hand defects in high voltage electrical burn wounds with reverse forearm flaps. Reverse radial fasciocutaneous flap were 3 cases, reverse ulnar fasciocutaneous flap were 3 cases, reverse ulnar fasciocutaneous flap and STSG were 4 cases, reverse ulnar fascial flap and STSG were 2 cases. We successfully reconstructed hand defects in all 12 cases, and obtained following conclusions. 1 Various reverse forearm flaps provide well vascularized, profitable tissues and they require short operative time with relatively easy procedures. 2. Reverse fascial flap and STSG, reverse fasciocutaneous flap and STSG provide thin flaps with good aesthetics and minor donor site morbidity.

• 한국경영과학회지
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• 제42권1호
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• pp.29-41
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• 2017

Korea is expected to become a super-aged society by 2050. Given an aging population and the increasing pressure for the early retirement, a sufficient social safety net for elderly population becomes important. The Korean government introduced public reverse mortgage program in 2007, which is a product for aging seniors and the elderly, The number of reverse mortgage subscribers has also steadily grown. The demand continues to grow, but the reverse mortgage over a long period of time is a highly uncertain and risky product in the position of guarantee or lending institution. Thus, suitable demand prediction of the reverse mortgage subscribers is necessary for stable and sustainable operation. This study uses a Bass diffusion model to forecast the long-term demand for reverse mortgage and provides insight into reverse mortgage by forecasting demand for stability and substantiality of the loan product. We represent the projections of new subscribers on the basis of the data obtained from Korea Housing Finance Corporation. Results show that potential market size of Korean reverse mortgage reaches approximately 760,000-1,160,000 households by 2020. We validate the results by comparing the estimate of the cumulative number of subscribers with that found in literature.

• 한국전기전자재료학회논문지
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• 제19권2호
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• pp.185-188
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• 2006

We studied on the reverse twist near the pixel edge depending on the rubbing direction for the fringe field switching (FFS) mode. Liquid crystal (LC) dynamic and the transmittance near the pixel edge, where the various field directions are generated, depend on the initial rubbing direction because the position of reverse twist is decided by the angle between the electric direction and the LC director at a bias voltage. For example, when the rubbing angle is $7^{\circ}$, the reverse twist appears on the bottom position of the right sharp comer of the pixel edge so that the reverse region exists far away from main active region. But, when the rubbing angle is $-7^{\circ}$, the reverse twist appears on the top position of the right sharp comer of the pixel edge, resulting that the region becomes more close to the main active area and the unstable disclination lines (DLs) easily intrude into the active region. Therefore, it is necessary to keep the reverse twist region far from the active region and it is possible by controlling the rubbing direction in the design of a pixel electrode.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권4호
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• pp.1931-1953
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• 2017

The reverse skyline query plays an important role in information searching applications. This paper deals with continuous reverse skyline queries in sensor networks, which retrieves reverse skylines as well as the set of nodes that reported them for continuous sampling epochs. Designing an energy-efficient approach to answer continuous reverse skyline queries is non-trivial because the reverse skyline query is not decomposable and a huge number of unqualified nodes need to report their sensor readings. In this paper, we develop a new algorithm that avoids transmission of updates from nodes that cannot influence the reverse skyline. We propose a data mapping scheme to estimate sensor readings and determine their dominance relationships without having to know the true values. We also theoretically analyze the properties for reverse skyline computation, and propose efficient pruning techniques while guaranteeing the correctness of the answer. An extensive experimental evaluation demonstrates the efficiency of our approach.

• Nuclear Engineering and Technology
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• 제52권9호
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• pp.1955-1962
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• 2020

In a sudden shutdown of primary pump or coolant loss accident in a marine nuclear power plant, the primary flow decreases rapidly in a transition process from forced circulation (FC) to natural circulation (NC), and the lower flow enters the steam generator (SG) causing reverse flow in the U-tube. This can significantly compromise the safety of nuclear power plants. Based on the marine natural circulation steam generator (NCSG), an experimental loop is constructed to study the characteristics of reverse flow under middle-temperature and middle-pressure conditions. The transition from FC to NC is simulated experimentally, and the characteristics of SG reverse flow are studied. On this basis, the experimental loop is numerically modeled using RELAP5/MOD3.3 code for system analysis, and the accuracy of the model is verified according to the experimental data. The influence of the flow variation rate on the reverse flow phenomenon and flow distribution is investigated. The experimental and numerical results show that in comparison with the case of adjusting the mass flow discontinuously, the number of reverse flow tubes increases significantly during the transition from FC to NC, and the reverse flow has a more severe impact on the operating characteristics of the SG. With the increase of flow variation rate, the reverse flow is less likely to occur. The mass flow in the reverse flow U-tubes increases at first and then decreases. When the system is approximately stable, the reverse flow is slightly lower than obverse flow in the same U-tube, while the flow in the obverse flow U-tube increases.