• Journal of the Korean Data and Information Science Society
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• v.26 no.3
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• pp.639-652
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• 2015

In today's manufacturing environment, the process data can be easily measured and transferred to a computer for analysis in a real-time mode. As a result, it is possible to monitor several correlated quality variables simultaneously. Various multivariate statistical process control (MSPC) procedures have been presented to detect an out-of-control event. Although the classical MSPC procedures give the out-of-control signal, it is difficult to determine which variable has caused the signal. In order to solve this problem, data mining and machine learning techniques can be considered. In this paper, we applied the technique of decision tree learning to the MSPC, and we did simulation for MSPC procedures to monitor the bivariate normal process means. The results of simulation show that the overall performance of the MSPC procedure using decision tree learning technique is similar for several values of correlation coefficient, and the accurate classification rates for out-of-control are different depending on the values of correlation coefficient and the shift magnitude. The introduced procedure has the advantage that it provides the information about assignable causes, which can be required by practitioners.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.3
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• pp.305-316
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• 2011

Cracked teeth are a common problem with incomplete fracture that typically shows pain on biting and temperature stimuli. The most common cause of crack is known to be the masticatory accident. Predisposing factors were aging, old restoration, and iatrogenic stress concentration, etc. Accurate diagnosis is needed for detecting the extent of crack and pulp vitality. There are many diagnostic tools like bite test, direct observation with transillumination, dye penetration, and radiographs. Immediate treatment for pain relief and occlusal adjustment would be needed. Composite resin and bonded amalgam showed favorable prognosis. Moreover, cusp protection is reliable permanent treatment for cracked teeth. The purpose of this article is to review the literature about the prevention, diagnosis, and treatment for cracked teeth.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.2223-2231
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• 2010

Recently, an important physical device of transportation, such as car, railroad, ship and aircraft has changed into electronic control unit. According to accident reports, the most of car accidents are caused by faults of embedded software loaded to computer control unit. The facts implies that the test to find defects in embedded software haven't performed sufficiently. As a result, it is necessary to establish the test procedures of embedded software based on safety assessment criteria. The objective of this proposal is to provide a unit test procedure complied with the safety assessment criteria for the embedded software. In addition, an effective unit testing procedure and defect analysis methods are proposed and a testing procedure using a safety criteria built-in tool is presented.

• Journal of fish pathology
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• v.26 no.1
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• pp.39-44
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• 2013

Saprolegnia isolate from wild brook lamprey was identified on the basis of its morphological and molecular characteristics. The isolates showed aseptic hyphae and clavate zoosporagium. Zoospores discharge was typically saprolegnoid. Neither oogomia nor antheridia was observed in this study. ITS sequence obtained from the isolate was compared with other Saprolegnia spp. to analyse their phylogenetic relationships. Results showed that the isolate belongs to clade I including Saprolegnia parasitica. Based on the asexual organs, zoospore discharge manner and ITS sequence analysis, the isolate was identified as S. parasitica.

• Journal of Fisheries and Marine Sciences Education
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• v.6 no.2
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• pp.190-197
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• 1994

In this paper, 2513 marine casualties occurred in Korean waters, during 1989-1993, were analysed by the Multivariate Data Analysis Method. The main results obtained were as follows : 1. Moat of marine casualties resulted from the human factors such as careless operation and insufficient engine maintenance. Engine trouble accounted for main patten of accidents and great number of accidents occurred in fishing vessels. 2. From the point of view of the damage of human life and properties, accidents took place in cargo ships, passenger ships and tankers were serious, but in fishing vessels, those were not so serious. 3. Grounding, collision mainly resulted from careless operation, however flooding and capsizing were much affected by bad weather and material defect.

• The Journal of the Korea Contents Association
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• v.12 no.11
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• pp.58-67
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• 2012

It is widely observed in the Korean broadcasting production industry that unfair trade practices occur either when the drawing up a contract is ill-timed, when the contract's stipulations do not adequately cover possibilities in reality, or when the contract is simply breached. In particular, the most prevalent cause of the breach of contracts lies in the broadcasting production practices. Hence, systematic efforts should be made to improve the daily practices of the production industry by ensuring that the whole production process is carried out by contract. In order to achieve this, the following are suggested: i) A preliminary contract is to be made prior to the main one. ii) A standard production contract, which can be used as a template for other sub-contracts such as writing contracts, acting contracts, employment contracts, and so on, needs be introduced. iii) The standard contract should stipulate the obligations of the personnel from broadcasting companies, the recognition of the rights of production companies that created formats, and the boundary of the autonomy that production companies can exercise during production, in particular. iv) Prohibitive provisions are to be introduced into the Broadcasting Law in order to limit the causes for unfair trade practices.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.2
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• pp.465-472
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• 2016

Principal Component Analysis (PCA) is useful statistical technique for finding patterns in data, and expressing the data in such a way as to highlight their similarities and differences. In this paper, 1417 marine casualties occurred in Korean littoral sea in recent 5 years, were examined by the PCA. The main results obtained were as follows : 1. Most of marine casualties resulted from the human factors such as careless operation and insufficient engine maintenance. 2. Collision and standing mainly resulted from steering room-related human factors such as careless guard, inadequate ship-handling, however engine damage and fire explosion mainly resulted from engine room-related human factor such as bad handling of engine system. 3. No. 1 principal component represents accident frequency, No. 2 principal component represents the cause and No. 3 principal component represents the pattern of marine casualties, respectively.

• Fire Science and Engineering
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• v.24 no.1
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• pp.103-110
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• 2010

Farming activity was the second cause of forest fire following the carelessness. In this study, 74 forest fires caused by farming activity and waste burning in 2009 was investigated for analyzing ignition patterns. The main cause to bring about forest fire was the farming waste burning as 25 cases, burning of farming waste matter after product and household waste burning were the second causes as 19 cases. Landcovers which transfer flame from ignition point to forest were fallow field graveyard, field fruit farm, field levee fallow field. The average distance between ignition point and forest sleeve was 19 m, and the maximum distance was 130 m. The probability of forest fire ignition was high in the 100 m buffer zone from the forest sleeve that is the prohibition rule of fire use for forest fire prevention at the forest fire season.

• Journal of the Korea Institute of Building Construction
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• v.20 no.6
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• pp.527-535
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• 2020

This study analyzed main causes of claims in EPC/Turnkey projects. For this purpose, this study referred to the FIDIC silver book, which lists the international standard contract conditions for EPC/Turnkey projects. The most frequent cause of claim was delay. A process was then proposed to determine whether the owner or contractor was the responsible party when the delay claim occurred. The proposed process was for damages for delay which is the conditions of contract for indemnities against delay claim. The process was based on conditions of the contract of two previous EPC/Turnkey projects that were constructed in 2010, the FIDIC silver book, as well as the obligations of owner and contactors. The proposed process is applicable depending on the conditions of the contract and the owner's meaning. Furthermore, by identifying the responsible party, this study will contribute in identifying the possible claim types before concluding a contract and writing the specific contract.

• Journal of the Korean Society of Radiology
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• v.81 no.4
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• pp.794-805
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• 2020

Acute abdomen is a condition with sudden abdominal pain that may require immediate surgical treatment. The causes of acute abdomen in pediatric patients are diverse, and can be categorized in broad range from diseases requiring surgery to diseases requiring medication or clinical observation only. The role of the imaging study in children with acute abdomen is to distinguish between patients who need medication and patients who need surgery by identifying diseases that cause abdominal pain, if possible. Since intussusception and appendicitis are the leading causes of acute abdomen requiring surgical treatment in children, it is important to exclude intussusception in young infants complaining of acute abdominal pain and exclude acute appendicitis in older children with acute abdomen. In this paper, we introduce intussusception, acute appendicitis, midgut volvulus, Meckel's diverticulum and duplication cyst, which has characteristic imaging finding of the disease that can cause acute abdomen in pediatric patients.