• Journal of Navigation and Port Research
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• v.43 no.4
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• pp.250-255
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• 2019

The objective of this study was to analyze the risk of collision accidents to the VTSOs (Vessel Traffic Service Operators) as small ferries and fishing boats are expanded for monitoring targets. The VTSOs was surveyed, the scale of the small vessels defined and the course of general cargo vessels and small vessels along the Busan VTS area investigated for three days. From calculating the risk with CoRI, patterns of increased or decreased risk due to course deviation were similar, and there was no significant difference between the maximum values and the minimum values. In addition, most VTSOs responded that the minimum time required was approximately three minutes to safely instruct in encounter situation, however, the collision risk with a small vessel is very rapidly changing within the three minutes, which is likely to increase the workload and decrease the concentration of the VTSOs. The objective of this study was to investigate the effect on VTSOs with respect to the expansion of small vessels as collision risk, it is expected that it will contribute to the establishment of a suitable scale for the target vessels for VTS through the analysis of each index of the CoRI model and various case studies.

• Journal of Navigation and Port Research
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• v.45 no.3
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• pp.117-129
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• 2021

This study intends to verify the effectiveness of incentive schemes at Busan Port' aimed at promoting transshipment cargo. The current incentive schemes of Busan port intended to increase the T/S cargo volume have been disputed constantly. It is imperative, therefore, to restructure the system in accordance with the planned strategy. In this study, in order to ensure objectivity of the incentive schemes, all the parties (carriers, terminal operators and Port Authority) with a direct interest are answered and analyzed using the AHP methodology. Effectiveness is the top priority in the analysis of beneficiary validity of incentive schemes, when incentives are provided to Global overseas carriers compared with Global national carriers, IntraAsia carriers and Terminal operators. In the analysis of incentive schemes, direct cash support corresponding to the quantity of the T/S cargo had the highest effectiveness compared with exemption of port dues, cost compensation, port infrastructure support and subsidy for the service opening. The study results, therefore, reference the Port Authority when restructuring the schemes. This study has been conducted only focusing on the Busan port; however, the findings may have significant implications for overseas Port Authorities intending to implement incentive systems to promote cargo volumes similar to those at Busan port.

• Korean Journal of Human Ecology
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• v.19 no.2
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• pp.325-341
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• 2010

A study on what kind of problems young consumers experience in buying and using mobile phone services with a comprehensive and consumers oriented perspective is needed. Through this acknowledgement, we investigated (i) the degree of consumer problems that young consumers experience in purchasing and using mobile phone services, and (ii) the related variables that affect experiences of this consumer problem. The parents of the teenagers were also included in the survey because they experience the same problems young consumers' experience in buying and using mobile phone services. Data were gathered through an internet survey (www.embrain.com) and a total of 699 samples from 350 parents and 349 youths using mobile phone services were analysed. The results are as follows. First, the teenagers and parents' experience level of young consumers' problems were generally high experiencing similar kinds of problems. Second, parents experienced more young consumers' problems than the teenagers in buying and using mobile phone services, especially in misuse and abuse of the phones. Third, among the teenagers, the monthly usage fee music or game usage, the number of changes in mobile phone service operators, the number of replacement mobile phones and the gender had a significant effect on consumers' problems of mobile phone services. Among the parents, the monthly usage fee, music or game usage, confirmation of the bill, and the gender of their child were significant consumer problems. Based on results of our survey the direction of consumer policy and education was suggested for teenagers and their parents.

• Journal of Digital Convergence
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• v.10 no.9
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• pp.375-381
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• 2012

If a mobile station requests a channel allocation in its mobile networks, the switching center assigns a channel to a mobile station that belongs to each base station. There are three kinds of channel allocation schemes; a fixed channel allocation, a dynamic channel allocation and a hybrid combination of these two forms. In assigning a good frequency, it is our intention to provide quality service to our customers as well as to use resources efficiently. This paper proposes methods of assigning frequencies that minimize interference between channels and that also minimize the amount of searching time involved. In this paper, we propose an algorithm to per specific equipment, regardless of the number of channels that can be used as a general-purpose system, such as base stations, control stations, central office model is proposed, the existing operators manner similar to the fixed channel allocation based statistics and assigned when the conventional method and the improved method is proposed. Different ways and compared via simulations to verify the effectiveness of the proposed approach.

• Journal of Korean Society of Water and Wastewater
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• v.31 no.1
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• pp.63-72
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• 2017

For economic evaluation of integrated operation to sewage facilities, benefit-cost analysis was performed to watershed sewage works project in 7 watershed areas, 156 facilities. In this study, the cost before and after integrated operation was compared and benefits are calculated from the reduction of operators, increasement treated pollution loads, reduction cost through operation convenience, reduction water consumption through effluent reuse, and improvement of life benefit. The result showed that cost was 8,500million won and benefit was 16,747million won, so benefit was 49% higher than cost. B/C analysis result showed that B/C ratio was 1.97 and it is similar to other researches. The benefits of integrated operation included convenience of data management, increase of emergency response, decrease of complains with sewage which was not reflected numerically, so the benefits of integrated operation were expected much greater than this result

• Journal of the Korean Society for information Management
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• v.23 no.2
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• pp.61-79
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• 2006

To come up with the recommendations to improve the patent & trademark retrieval efficiency, 100,016 patent & trademark search requests by 17,559 unique users over a period of 193 days were analyzed. By analyzing 2,202 multi-query sessions, where one user issuing two or more queries consecutively, we discovered a number of retrieval efficiency improvements clues. The session analysis result also led to suggestions for new system features to help users reformulating queries. The patent & trademark retrieval users were found to be similar to the typical web users in certain aspects especially in issuing short queries. However, we also found that the patent & trademark retrieval users used Boolean operators more than the typical web search users. By analyzing the multi-query sessions, we found that the users had five intentions in reformulating queries such as paraphrasing, specialization, generalization, alternation, and interruption, which were also used by the web search engine users.

• Culinary science and hospitality research
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• v.7 no.3
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• pp.193-209
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• 2001

The result of this study suggests that students' perception of service value is related to functional value with regard to need and satisfaction, epistemic value, image, emotional value, functional value with regard to price and quality, and social value. Specifically female students give less importance to epistemic value than their male counterparts. Students in the 2nd grade gave less favorable scores to the functional value with regard to need and satisfaction, epistemic value, image, emotional value and functional value with regard to price and quality than students in the 1st grade. Students in the night class gave less scores to epistemic value and functional value with regard to price and quality than students in the day class. It is confirmed that the difference between groups by the period in school is in functional value with regard to need and satisfaction, image, emotional value, and functional value with regard to price and quality. And it is also revealed that these results are similar to the results of analysis by the grade. In conclusion college operators should not overemphasize that the department of Hotel culinary arts occupies the leading position of the culinary academic world in Korea and the firms of food service industry positively evaluate the department of Hotel culinary arts, and in order to cope with the rapidly changing environment of the culinary education consistent investment constant changes and of efforts should not be stopped. On one hand the teaching staff of the department of Hotel culinary arts should reconsider their original role, and need behavior and practice to fill their deficiency with steady efforts in terms of students' perceived service value. In addition the students of the department of Hotel culinary arts should not be shackled by the past tradition, should not take a pessimistic view of the present situation, should not take an optimistic view of the future, and should always cultivate their ability to provide for the future.

• Journal of Industrial Technology
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• v.29 no.B
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• pp.221-228
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• 2009

For a stable supply of electric power, periodical inspection of the electric facilities and repair of the distribution lines are required. In case of any unexpected accidents, looped operation among distribution lines may be necessary in order to supply electricity through the sound lines, separating the faulted lines. As a result of this study, it was found that normal looped operation became impossible when phase difference of the looped distribution lines is more than 3 degrees compared with the voltage supply of the distribution lines. Therefore, for a stable supply of electric power to Chuncheon, it is judged to be desirable that looped operation of the distribution lines coming from the same substation M. Tr Bank shall be performed in principle and in case of looped operation with the substation of different system, looped operation among the lines shall be performed after voltage regulation of the substation M. Tr Bank, maintaining similar voltages and load supply volume in order to avoid phase difference through checking the operation conditions of each substation M. Tr Banks. And when looped operation among the distribution lines is scheduled, voltage regulation schedule has been established so far by calculating maximum supply volume through the transformer of the substation and the maximum load volume through the distribution lines but in the future, looped operation of the distribution lines shall be carried out by removing voltage difference with regulating tap or load of the surrounding transformers, with giving prior notice to the substation operators.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.4
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• pp.76-85
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• 2011

In this paper, we propose a texture feature-based language identification using Gabor feature and wavelet-domain BDIP (block difference of inverse probabilities) and BVLC (block variance of local correlation coefficients) features. In the proposed method, Gabor and wavelet transforms are first applied to a test image. The wavelet subbands are next denoised by Donoho's soft-thresholding. The magnitude operator is then applied to the Gabor image and the BDIP and BVLC operators to the wavelet subbands. Moments for Gabor magnitude image and each subband of BDIP and BVLC are computed and fused into a feature vector. In classification, the WPCA (whitened principal component analysis) classifier, which is usually adopted in the face identification, searches the training feature vector most similar to the test feature vector. Experimental results show that the proposed method yields excellent language identification with rather low feature dimension for a document image DB.

• Journal of Gastric Cancer
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• v.16 no.4
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• pp.240-246
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• 2016

Purpose: It is hypothesized that robotic gastrectomy may surpass laparoscopic gastrectomy after the operators acquire long-term experience and skills in the manipulation of robotic arms. This study aimed to evaluate the long-term learning curve of robotic distal gastrectomy (RDG) for gastric cancer compared with laparoscopic distal gastrectomy (LDG). Materials and Methods: From October 2008 to December 2015, patients who underwent LDG (n=809) were matched to patients who underwent RDG (n=232) at a 1:1 ratio, by using a propensity score matching method after stratification for the operative year. The surgical outcomes, such as trends of operative time, blood loss, and complication rate, were compared between the two groups. Results: The RDG group showed a longer operative time (171.3 minutes vs. 147.6 minutes, P<0.001) but less estimated blood loss (77.6 ml vs. 116.6 ml, P<0.001). The complication rate and postoperative recovery did not differ between the two groups. The RDG group showed a longer operative time and similar estimated blood loss compared with the LDG group after 5 years of experience (operative time: 159.2 minutes vs. 136.0 minutes in 2015, P=0.003; estimated blood loss: 72.9 ml vs. 78.1 ml in 2015, P=0.793). Conclusions: In terms of short-term surgical outcomes, RDG may not surpass LDG after a long-term experience with the technique.