• Nuclear Engineering and Technology
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• v.51 no.5
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• pp.1307-1313
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• 2019

Recent analysis results with realistic assumptions provide the variability of operator allowable time for the initiation of aggressive cooldown under small break loss of coolant accident or steam generator tube rupture with total failure of high pressure safety injection. We investigated how plant risk may vary depending on the variability of operators' failure probability of timely initiation of aggressive cooldown. Using a probabilistic safety assessment model of a nuclear power plant, we showed that plant risks had a linear relation with the failure probability of aggressive cooldown and could be reduced by up to 10% as aggressive cooldown is more reliably performed. For individual accident management, we found that core damage potential could be gradually reduced by up to 40.49% and 63.84% after a small break loss of coolant accident or a steam generator tube rupture, respectively. Based on the importance of timely initiation of aggressive cooldown by main control room operators within the success criteria, implications for improvement of emergency operating procedures are discussed. We recommend conducting further detailed analyses of aggressive cooldown, commensurate with its importance in reducing risks in nuclear power plants.

• International Journal of Computer Science & Network Security
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• v.21 no.8
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• pp.28-34
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• 2021

Internet Service Providers (ISPs) constantly endeavor to resolve network congestion, in order to provide fast and cheap services to the customers. This study suggests two models based on Markov chain, using three and four access attempts to complete the call. It involves a comparative study of four models to check the relationship between Internet Access sharing traffic, and the possibility of network jamming. The first model is a Markov chain, based on call-by-call attempt, whereas the second is based on two attempts. Models III&IV suggested by the authors are based on the assumption of three and four attempts. The assessment reveals that sometimes by increasing the number of attempts for the same operator, the chances for the customers to complete the call, is also increased due to blocking probabilities. Three and four attempts express the actual relationship between traffic sharing and blocking probability based on Markov using MATLAB tools with initial probability values. The study reflects shouting results compared to I&II models using one and two attempts. The success ratio of the first model is 84.5%, and that of the second is 90.6% to complete the call, whereas models using three and four attempts have 94.95% and 95.12% respectively to complete the call.

• Journal of the Korea Society for Simulation
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• v.31 no.1
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• pp.19-27
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• 2022

This study compares and analyzes wholesale(or price-only) contract, revenue-sharing contract, quantity-flexibility contract, and channel-rebate contract in a decentralized supply chain consisting of one supplier and one retailer. By setting the parameters of each coordination contract based on the previous results, we conduct simulations using @RISK for several combinations of these parameters. Under the supply chain coordination, we evaluate the probability of successfully signing a contract and the participant in favor of each contract. As a result, the quantity-flexibility contracts is most advantageous for the retailer and the channel-rebate contracts is most advantageous for the supplier. It revealed that revenue-sharing contracts can be used more flexibly because they can be selected in the widest range to redistribute profits between supplier and retailer.

• Journal of Technology Innovation
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• v.20 no.3
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• pp.57-91
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• 2012

This paper investigates determinants of litigation success in the two distinctive types of patent litigations, ex-parte and inter-parte cases, which are brought in the process where a filed application becomes a valid patent right. We regress winning rates of patent applicants on the characteristics of firms, trials, patent lawyer, and patent itself, using a probit model with sample selections. The paper finds that the relative suit rate of a firm, time to be sued, changes of patent agents by applicants, and multiple agents among explanatory variables affect ex-parte reexamination and in-parte post-grant patent trials differently in the point of average marginal effects. These variables lower the probability of applicant's victory in the ex-parte cases, while they raise the probability in the inter-parte trials. However, the experience that agents represent applicants is a winning rate-increasing factor both in inter-parte and ex-parte reexamination, unexpectedly. This result cannot be applied to the entire domain of the variable, since sample selection effects are reflected in the result. The number of claim increases the winning probability of the applicant in the both types of patent litigations. This study has some limitations because it ignores the information on the legal person to which a patent agent belongs, and confined agent's experience to patent filing. We leave it future studies to investigate the effects of lawsuit experience of patent agent, and those of characteristics of the law firm to which individual patent lawyer is affiliated.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.1
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• pp.127-133
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• 2020

This paper deals with the development of a smart mirror to support changing hair styles. A key function of the service is the ability to synthesize the image into the user's face when the user chooses a desired hair image and virtually styling the hair. To check the effectiveness of the hair image synthesis function, the success rate measurement experiment of Haar-cascade algorithm's facial recognition was conducted. Experiments have confirmed that the facial recognition succeeds with a 95 percent probability, with both eyes and eyebrows visible to the subjects. It is the highest success rate. It confirmed that if either of the eyebrows of the subjects are not visible or one eyeball is covered, the success rate of facial recognition is 50% and 0% respectively.

• Journal of Digital Convergence
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• v.11 no.9
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• pp.341-348
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• 2013

The present study aims to analyze kickers' strategic actions for finishing in penalty shoot-outs among youth soccer players ultimately to increase success rates of shoot-outs and to score a victory. Subjects were experienced 271 soccer players attending high schools located around the capital area. To determine any difference in strategic actions for finishing in penalty shoot-outs among the subjects, frequency analysis or chi-square was used for the analysis. The analysis found the following points: First, the success or failure rates of kickers in penalty shoot-outs were found to depend on subjects' experiences as soccer players. Second, in terms of kickers' shooting qualities, they were found to shoot on goal regardless of shooting positions. Third, an important factor to enhance the shoot-outs probability was found to be a strategic action through the eyes. Fourth, in view of the strategic actions prior to kickers' shooting, goalies were found to check out kickers' positions first and estimate the directions and qualities of shooting via kickers' body actions and eye lines.

• Archives of Reconstructive Microsurgery
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• v.26 no.1
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• pp.9-13
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• 2017

Purpose: Fingertip amputations are the most common type of upper limb amputations. Composite grafting is a simple and cost-effective technique. Although many factors have investigated the success of composite grafting, the success rate is not high. Therefore, this study was conducted to investigate whether the microscopic procedure process during composite grafts improves the success rate. Materials and Methods: Thirteen cases of unreplantable fingertip amputation underwent a microscopic resection procedure for composite graft in the operating room. The principle of the procedure was to remove the least devitalized tissue, maximize the clean tissue preservation and exact trimming of the acral vessel and to remove as many foreign bodies as possible. Results: All fingertips in the thirteen patients survived completely without additional procedures. Conclusion: Composite grafting allows for the preservation of length while avoiding the donor site morbidity of locoregional flaps. Most composite grafts are performed as quickly as possible in a gross environment. However, we take noticed the microscopic resection. This process is thought to increase the survival rate for the following reasons. First, the minimal resection will maximize the junction surface area and increase serum imbibition. Second, sophisticated trimming of injured distal vessels will increase the likelihood of inosculation. Third, accurate foreign body removal will reduce the probability of infection and make it possible to increase the concentration and efficiency in a microscopic environment. Although there is a need for more research into the mechanisms, we recommend using a composite graft under the microscopic environment.

• Journal of Technology Innovation
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• v.18 no.2
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• pp.175-219
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• 2010

Since diversification can be a necessary means for company's survival and the conservation of its success, hundreds of studies have been done by three schools of industrial economics, strategic management, and Neo-Schumpeterian economics for over 30 years. However, any school has not presented a model comprehensively explaining diversification' success or failure. The study tried to suggest a theoretical framework integrating findings came from three schools. The framework considers both firm's technological capabilities and sector-specific characteristics as well as reflects a Neo-Schumpeterian view emphasizing technological aspects. The goal of the study is finding major reasons of success and failure during company's diversification through studying three diversification cases of Samsung. Our findings show that the diversification toward TFT-LCD was easier and more successful than the diversification toward microprocessor because DRAM is more similar to TFT-LCD than microprocessor. Samsung also tended to build only the types of capabilities which were originated from capabilities accumulated in DRAM business. Our findings give firm's strategists a lesson that they can increase the probability of success in diversification, if only they should simultaneously consider a new sector's characteristics, a firm's technological capabilities accumulated in old sectors, and the availability of old capabilities for being applied to a new sector.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.6
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• pp.3188-3207
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• 2017

In this paper, we propose an image enhancement algorithm to improve license plate extraction rate in various environments (Day Street, Night Street, Underground parking lot, etc.). The proposed algorithm is composed of image enhancement algorithm and license plate extraction algorithm. The image enhancement method can improve an image quality of the degraded image, which utilizes a histogram information and overall gray level distribution of an image. The proposed algorithm employs an interpolated probability distribution value (PDV) in order to control a sudden change in image brightness. Probability distribution value can be calculated using cumulative distribution function (CDF) and probability density function (PDF) of the captured image, whose values are achieved by brightness distribution of the captured image. Also, by adjusting the image enhancement factor of each part region based on image pixel information, it provides a function that can adjust the gradation of the image in more details. This processed gray image is converted into a binary image, which fuses narrow breaks and long thin gulfs, eliminates small holes, and fills gaps in the contour by using morphology operations. Then license plate region is detected based on aspect ratio and license plate size of the bound box drawn on connected license plate areas. The images have been captured by using a video camera or a personal image recorder installed in front of the cars. The captured images have included several license plates on multilane roads. Simulation has been executed using OpenCV and MATLAB. The results show that the extraction success rate is more improved than the conventional algorithms.

• Journal of Distribution Science
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• v.10 no.3
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• pp.7-13
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• 2012

Recently, with the success of Groupon in the USA using the new business model referred to as social commerce, which is a commercial transaction involving group purchases on social network service (SNS), social commerce business receives much attention. Social commerce is capable of effectively promoting additional purchasing by customers through unprecedented price discounts and limiting the number of purchasers and time allotted for purchases, and is able to achieve promotional effects over and above those of simple product promotion due to customers' voluntary word of mouth. Although social commerce is effective for short-term increase in the sales of products, there are numerous dissenting opinions on whether it can promote repurchasing by customers. In particular, social commerce in Korea focuses only on unprecedented discounted prices and does not have the marketing effect that SNS can produce over and above the sales promotion. The objective of this study is to find the factors that influence the repurchase intention on social commerce and to analyze factors that contribute the social commerce product. For this, this study extracts repurchase intention factors and computes a repurchase probability to assess the influence of factors other than price discount on social commerce customers at the time of repurchasing. In addition, the importance of factors toward sales revenue for each of the social commerce products (e.g., restaurant/café, beauty, tour/leisure, show/exhibition, and fashion/clothes) is estimated by using the computed repurchase probabilities. The repurchase probability through the analysis can be used for development of social commerce business in Korea.