• Journal of Korea Port Economic Association
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• v.37 no.1
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• pp.31-70
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• 2021

The purpose of this paper is to measure the clustering change and analyze empirical results, and choose the clustering ports for Busan, Incheon, and Gwangyang ports by using Hierarchical clustering(single, complete, average, and centroid), Silhouette, and 2SCE[the Second Stage(Type II) cross-efficiency] matrix clustering models on Asian container ports over the period 2009-2018. The models have chosen number of cranes, depth, birth length, and total area as inputs and container TEU as output. The main empirical results are as follows. First, ranking order according to the efficiency increasing ratio during the 10 years analysis shows Silhouette(0.4052 up), Hierarchical clustering(0.3097 up), and 2SCE(0.1057 up). Second, according to empirical verification of the Silhouette and 2SCE models, 3 Korean ports should be clustered with ports like Busan Port[ Dubai, Hong Kong, and Tanjung Priok], and Incheon Port and Gwangyang Port are required to cluster with most ports. Third, in terms of the ASEAN, it would be good to cluster like Busan (Singapore), Incheon Port (Tanjung Priok, Tanjung Perak, Manila, Tanjung Pelpas, Leam Chanbang, and Bangkok), and Gwangyang Port(Tanjung Priok, Tanjung Perak, Port Kang, Tanjung Pelpas, Leam Chanbang, and Bangkok). Third, Wilcoxon's signed-ranks test of models shows that all P values are significant at an average level of 0.852. It means that the average efficiency figures and ranking orders of the models are matched each other. The policy implication is that port policy makers and port operation managers should select benchmarking ports by introducing the models used in this study into the clustering of ports, compare and analyze the port development and operation plans of their ports, and introduce and implement the parts which required benchmarking quickly.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.2
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• pp.36-42
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• 2011

The current healthcare information systems field to meet the growing demand for healthcare for a variety of building systems and operation, and subsequent information on the budget continues to increase, but the current system, although the association link between the various systems made does not, with organizations with information about each of the standardization and real-time network status data do not consist of various materials, such as insufficient to provide real-time issues have been raised. This paper proposes a Integrated information system on Healthcare based on JXTA to solve problems mentioned above. Until now, in a network environment for data storage and management is the most widely used server-intensive structure, while an increase in users and traffic difficulties in data management and communications services to handle the growing number of servers increase faster than information associated with the cost savings, P2P model in terms of efficient data management has emerged as a new solution. Therefore this paper designs a platform for Integrated information system on Healthcare based on JXTA as a method to integrate health information data and services, and then proves that the new information system on healthcare based on JXTA is the suitable model.

• The Journal of the Korea Contents Association
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• v.10 no.6
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• pp.258-274
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• 2010

Along with hardware implementation of cultural arts, the importance of cultivating and securing professionals who are able to operate and mange it from the political perspective is highlighted as a political issue. In addition, with growing public demand for culture, performing arts are enlarged and professionalized, and this increased the number of large-scale musicals and activated exchanges with overseas performances, which raised the demand for personnel of performing technology. Like this, growing theaters require professionals in the performing technology field for technically safe and quality performance. The certification system for performing arts professionals is to develop quality of theaters and performing arts by increasing vocational professionalism and safety in the performing technology field. This system performed since 2000 is getting positioned, and employees who worked for the performing technology field at this time showed a lot of attentions with certainty they would receive credit for artistic professionalism and raise pride as a performing arts professional. However, the government's political strategy to secure professionals of cultural arts and interest in human resource(HR) policy in the performing arts field were relatively insufficient. Therefore, this study examined the problems by looking into actual conditions regarding operation and role under the initial purpose of the certification system, and purposed the improvement plan as a first certification system to cultivate Korean performing arts professionals.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.59-67
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• 2017

This study analyzes the efficiency of oriental hospitals using DEA(Data Envelopment Analysis). The input variables include the numbers of doctors, nurses, medical technicians, and beds. The output variable iscomprised of the sales account. The analysis tools used are EnPas and IBM SPSS Statistics 19. As a result of efficiency analysis, the private hospitals(establishment), less than 10 years in operation(operating period), containing less than 50 beds (number of the beds), located in the metropolitan area(location) showed high efficiency in the BCC(Banker, Charnes & Cooper) model, but indicated relatively low efficiency in CCR(Charnes, Cooper & Rhodes) model. This contradictory result is caused by inefficiencies in hospital size. The logistic regression analysis conducted to analyze the variables that affect the efficiency of oriental hospitals found that the efficiency decreased by 0.955 with each increase of 1 bed in the hospital.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.12 no.4
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• pp.11-21
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• 2013

The conventional real-time signal control strategy for oversaturated situation generally requires a number of detectors at the intersection in order to identify the queue length at each approach. Also, existing strategy for the spillback has limited effect due to the temporal spillback control which only reduce the green split at the approach. In this study, a signal control system utilizing the imagery information from ITS roadside equipment is developed for operation of oversaturated intersections. The strategy calculates the saturation ratio based on the queue length extracted from ITS RSE, and designs the signal control variables according to the saturation ratio. The signal control strategy is divided into two phases: oversaturated and supersaturated. In oversaturated conditions, timing plan for main approach is optimized by the queue length. In oversaturated conditions where spillback might occur, the signal timing is designed in order to avoid the spillback. To increase field adaptability, the strategy is designed to adjust the split length, all-red-time, and clearance time, and keep the major signal control variables intact. The result of the simulation shows that in oversaturated conditions, the improvement is similar to the real-time signal control system. In case of, oversaturated conditions, however, the effect of the strategy is superior to that of a real-time system.

• The Journal of the Acoustical Society of Korea
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• v.32 no.6
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• pp.548-555
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• 2013

The localization of sources has a numerous number of applications. To estimate the position of sources, the relative delay between two or more received signals for the direct signal must be determined. Although the generalized cross-correlation method is the most popular technique, an approach based on eigenvalue decomposition (EVD) is also popular one, which utilizes an eigenvector of the minimum eigenvalue. The performance of the eigenvalue decomposition (EVD) based method degrades in the low SNR and the correlated environments, because it is difficult to select a single eigenvector for the minimum eigenvalue. In this paper, we propose a new adaptive algorithm based on Canonical Correlation Analysis (CCA) in order to extend the operation range to the lower SNR and the correlation environments. The proposed algorithm uses the eigenvector corresponding to the maximum eigenvalue in the generalized eigenvalue decomposition (GEVD). The estimated eigenvector contains all the information that we need for time delay estimation. We have performed simulations with uncorrelated and correlated noise for several SNRs, showing that the CCA based algorithm can estimate the time delays more accurately than the adaptive EVD algorithm.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.3
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• pp.207-212
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• 2007

This paper aims to measure and evaluate the technical efficiency with two inputs and four outputs with the use of fuzzy DEA in Korean RCC/RSC. Especially, this paper included not only the marine accident data which occurred for the analysis in particular but also the possibility data of a potential marine accident by an Environmental Stress value and analyzed the technical efficiency. And in this paper, asymmetrical triangular fuzzy number is presented about inputs/ outputs data and a procedure is suggested for it's solution. The basic idea is to transform the fuzzy CCR model into a crisp linear programming problem by applying an alternative ${\alpha}$-cut approach. Also this paper propose a ranking method for fuzzy RCC/RSC using presented fuzzy DEA approach. The result, when ${\alpha}$-cut is 0.5, efficiency priority is found in the order of YS, BS, MP, TY, JJ, PH, US, IC, SC, DH, GS, TA, WD RCC/RSC. Finally, Inefficiency TA, WD RCC/RSC have to benchmarking with reference sets.

• Journal of Chest Surgery
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• v.29 no.2
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• pp.171-176
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• 1996

From March, 1983 to June, 1994, twenty-two patients underwent coronary artery and combined operations. The ages of the patients ranged from 42 years to 72 years (mean 60.4$\pm$8.2 years). There were 17 male and 5 female patients. The left ventricular (LV) ejection fraction ranged from 25% to 65% (mean 46.9$\pm$14.2%). Nine patients had mechanical complication of myocardial infarction (MI), of which 5 were LV aneurysm, 3 ventricular septal defect and 1 mitral regurgitation. Nine patients had rheumatic valvular heart disease of whom 7 with aortic valve disease and 2 with mitral valve disease. Two other patients had left atrial thrombi, only one with atrial septal defect a d another with aneurysm of ascending aorta. An average of 2.1$\pm$1.0 bypasses was done, ranging from one to four. There were 3 postoperative complications; 2 perioperative MI and 1 leg wound infection. Among complicated patients, mortality was 1 patient (4.5%) due to low cardiac output syndrome after perioperative MI. With 3 to 136 months follow-up (mean 41.1$\pm$40.2 months), late mortality was 1 patient due to cerebral vascular accident. Among long-term survivors, all patients are in New York Heart Association functional class I or II. Although the number of patients was small, our surgical results were favorable. Therefore we think that coronary revascularization combined with heart operation does not increase the operative risk when associated coronary artery disease is present, and it reduces the occurrence of late death.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.2
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• pp.90-95
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• 2009

Sludge pre-treatment utilizing cavitation is one of the commercialized methods at present. Cavitation can be generated by two different methods, sonotrode and hydrodynamic principle, and there has been no direct comparison between the two methods. In this study, solubilization efficiency, changes in sludge size distribution, and the methane production potential after pre-treatment by the two methods were compared. The maximum solubilization efficiency per unit energy input with the two methods was similar, and was 302 mg ${\Delta}SCOD/g$ TS at the energy input of 0.18 kWh/L. Break-up of sludge flocs were dominant during the early period of pre-treatment, while cell disintegration continued through the pre-treatment with the increase in the number of particles with less than 1 ${\mu}m$. BMP test results indicated that the methane potential increased up to 24.3% without differences between the two pre-treatments, and the increase in methane potential did not proportional to energy input. Although the energy efficiency of the two methods was quite similar, hydrodynamic methods might be a better choice for field application considering the operation and maintenance cost, and its potential improvement in energy efficiency.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.6
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• pp.77-90
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• 2015

An increasing number of vehicles is causing various traffic problems such as chronic congestion of highways and air pollution. Local governments have been managing traffic by constructing systems such as Intelligent Transport Systems (ITS) and Advanced Traffic Management Systems (ATMS) to relieve such problems, but construction of an infrastructure-based traffic system is insufficient in resolving chronic traffic problems. A more sophisticated system with enhanced operational management capabilities added to the existing facilities is necessary at this point. As traffic patterns of the urban traffic flow is time-specific due to the different vehicle populations throughout the time of the day, a local network-wide signal operation plan that can manage such situation-specific traffic patterns is deemed to be necessary. Therefore, this study is conducted for the purpose of establishment of a plan for contextual signal control management through signal optimization at the network level after setting the Frame Signal in accordance to the traffic patterns gathered from the short-term traffic forecast data as a means to mitigate the problems with existing standardized signal operations.