• 한국경영과학회지
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• 제13권1호
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• pp.1-9
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• 1988

The purpose of this paper is study the sensitivity analysis of matrix game. Teh sensitivity analysis of matrix is classified into two types. Type one is to find the characteristic region of an element of the pay off matrix in which the value of the current optimal strategy remains as an optimum. Type two is to find that in which the basis of the current optimal strategy does not change. This paper shows the characteristic regions of basic and nonbasic strategies. Further it is found that the characteristic regions of type one and two are same in the case that the element is that of at least one player's nonbasic strategy.

• 품질경영학회지
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• 제31권3호
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• pp.193-204
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• 2003

In this paper, we consider a periodic preventive maintenance(PM) policy in which each PM reduces the hazard rate but remains the pattern of hazard rate unchanged. And the system undergoes only minimal repairs at failures between PM's. The expected cost rate per unit time is obtained. The optimal number N of PM and the optimal period x, which minimize the expected cost rate per unit time are discussed. Explicit solutions for the optimal periodic PM are given for the Weibull distribution case.

• 품질경영학회지
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• 제14권2호
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• pp.40-46
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• 1986

The decision maker has the job of torecasting capital investments and operating expenses to aid the decision making in choosing and evaluating present and future alternatives. The estimating function eventually analysis, evaluates and choose the alternatives. The analysis stemmed originally from a preliminary design of some sort, and eventually plans are started to investigate investment possibilites. This study provide the descounted cash flow and the present worth method. Despite any choice of an analytical method, there remains the problem of predicting certain future events. Therefore, these models dealing with optimum plant sizing, equipment replacement, and lease or buy will be discussed.

• Journal of Smart Tourism
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• 제2권4호
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• pp.11-23
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• 2022

The use of robots in tourism and hospitality contexts have drawn increasing scholarly and practical regard. Although the number of recent robotics related studies continue to grow, a general knowledge map, which is important to point out promising directions for future studies, remains to be made. To understand the application of robotics in tourism and hospitality, this study conducts descriptive and bibliometric analysis to present a holistic knowledge map of this specific field where research trend, key contributors, highly cited references, and popular themes were identified. Collaboration networks among institutes and regions were additionally illustrated. Collaboration across fields, industries, and perspectives were encouraged following the findings and both theoretical and practical implications are accordingly provided.

• Clinical and Experimental Reproductive Medicine
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• 제42권3호
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• pp.126-129
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• 2015

Essure (Bayer) received approval from the U.S. Food and Drugs Administration as a permanent non-hormonal contraceptive implant in November 2002. While the use of Essure in the management of hydrosalpinx prior to in vitro fertilization (IVF) remains off-label, it has been used specifically for this purpose since at least 2007. Although most published reports on Essure placement before IVF have been reassuring, clinical experience remains limited, and no randomized studies have demonstrated the safety or efficacy of Essure in this context. In fact, no published guidelines deal with patient selection or counseling regarding the Essure procedure specifically in the context of IVF. Although Essure is an irreversible birth control option, some patients request the surgical removal of the implants for various reasons. While these patients could eventually undergo hysterectomy, at present no standardized technique exists for simple Essure removal with conservation of the uterus. This article emphasizes new aspects of the Essure procedure, as we describe the first known association between the placement of Essure implants and the subsequent development of fluid within the uterine cavity, which resolved after the surgical removal of both devices.

• Clinical Endoscopy
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• 제55권1호
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• pp.58-66
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• 2022

Background/Aims: Anastomotic leakage after esophageal surgery remains a feared complication. During the last decade, management of this complication changed from surgical revision to a more conservative and endoscopic approach. However, the treatment remains controversial as the indications for conservative, endoscopic, and surgical approaches remain non-standardized. Methods: Between 2010 and 2020, all patients who underwent Ivor Lewis esophagectomy for underlying malignancy were included in this study. The data of 28 patients diagnosed with anastomotic leak were further analyzed. Results: Among 141 patients who underwent resection, 28 (19.9%) developed an anastomotic leak, eight (28.6%) of whom died. Thirteen patients were treated with endoluminal vacuum therapy (EVT), seven patients with self-expanding metal stents (SEMS) four patients with primary surgery, one patient with a hemoclip, and three patients were treated conservatively. EVT achieved closure in 92.3% of the patients with a large defect and no EVT-related complications. SEMS therapy was successful in clinically stable patients with small defect sizes. Conclusions: EVT can be successfully applied in the treatment of anastomotic leakage in critically ill patients, while SEMS should be limited to clinically stable patients with a small defect size. Surgery is only warranted in patients with sepsis with graft necrosis.

• 지식경영연구
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• 제13권4호
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• pp.13-29
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• 2012

Although the role of information systems (IS) on environmental sustainability much attention, the coordination between green practices and environmental management information systems (EMIS) in a firm remains unexplored area in environmental management and IS disciplines. This study elaborated the antecedents of the coordination between green practices and EMIS and then examines the links among them. Also, this study investigated the links from the coordination between green practices and EMIS to firm's environmental performance. The results showed that both attitudes of managers who are responsible for a firm's green practices and their support had direct effects on the coordination between green practices and EMIS. Also, consistent with environmental management literature, the study provides a better understanding of the relationship between the coordination between green practices and EMIS and environmental performance.

• Journal of Communications and Networks
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• 제15권2호
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• pp.153-163
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• 2013

In recent years, more and more researches have been focusing on trust management of vehicle ad-hoc networks (VANETs) for improving the safety of vehicles. However, in these researches, little attention has been paid to the location privacy due to the natural conflict between trust and anonymity, which is the basic protection of privacy. Although traffic safety remains the most crucial issue in VANETs, location privacy can be just as important for drivers, and neither can be ignored. In this paper, we propose a beacon-based trust management system, called BTM, that aims to thwart internal attackers from sending false messages in privacy-enhanced VANETs. To evaluate the reliability and performance of the proposed system, we conducted a set of simulations under alteration attacks, bogus message attacks, and message suppression attacks. The simulation results show that the proposed system is highly resilient to adversarial attacks, whether it is under a fixed silent period or random silent period location privacy-enhancement scheme.

• 셀메드
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• 제2권3호
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• pp.21.1-21.8
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• 2012

Heart disease that ultimately leads to heart failure (HF) has been the number one cause of death in the United States as well as in many other countries for over a century. Inotropic therapy utilizing cardiotonics to increase cardiac contractility remains a significant component of the management of HF. However, adverse effects of currently available cardiotonics have been compromising their therapeutic value and often lead to further myocardial dysfunction. Thus, discovery of safe cardiotonics remains a main challenge to improvement of inotropic therapy for HF. This review briefly summarized cellular mechanisms underlying the inotropic action of currently available cardiotonics, newly-developed carditonics and the bark of Terminalia arjuna (TA), a tropical tree used in ayurvedic medicine. The potential of TA bark as a new cardiotonic in inotropic treatment for HF was also discussed.

• Asian-Australasian Journal of Animal Sciences
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• 제11권6호
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• pp.769-773
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• 1998

Genetic advances, changes in housing systems and new management strategies have made it necessary to thoroughly review conventional nutritional programs. The approach has changed from one of feeding to permit gradual depletion of fat and protein tissues to one of feeding to maintain long-term nutritional balance. Increasingly the sow is viewed as a dynamic system that can be described by a mathematical model. There is opportunity to improve the initial models through research to provide a better understanding of metabolism and key physiological events in the sow's reproductive life. Direct experimentation remains a very important tool for defining nutritional requirements. Recent data supports increases in amino acid recommendations during lactation. Voluntary feed intake remains an intractable problem during lactation.