• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.3
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• pp.279-286
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• 2015

To achieve lightweight design, research & development of various lightweighting technologies such as hydroforming are underway worldwide. In the case of hydroforming, application of ultra high strength steel is essential for weight reduction of the car. However, considering common high-strength carbon steel, it is not suitable to the actual hydroformed parts since the lack of formability. DP steel offers an outstanding combination of strength and formability as a result of their microstructure. DP steel has high strength and good formability but it's difficult to secure stable quality of welding section because of softening of weld section and chemical composition. Therefore, most of companies use LASER welding when making high strength tube. Electric resistance welding is excellent production method for steel tube manufacturing considering the productivity. Optimum electric resistance welding technology is needed to be developed for application of high strength hydroformed parts using DP steel. This study is comprehensive research & development from electric resistance welding to actual formabililty evaluation.

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.6
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• pp.1027-1037
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• 2023

This paper presents an efficient method for generating informative apparel fit comments by analyzing 122 fit reviews found in 7 menswear patternmaking textbooks, which include both domestic and foreign sources. The fit reviews for menswear were categorized into top and bottoms, and the expressions varied based on body parts, causes, and fit issue appearances. The causes of fit issues could be attributed to size errors and structural errors in both top and bottoms. Both top and bottoms had fit reviews concerning unique body types, but it could cause trouble among learners as both were based on unclear criteria for body type classification and lacked relevant explanations. Common fit issue appearances included compound wrinkles, pulling wrinkles, sagging wrinkles, and garment being away from the body. No clear correlation was observed between the causes of fit issues and specific appearances. Limitations were identified in using textbooks as educational data, such as inconsistent solutions for different body types or fit issues, and the presence of ambiguous visual materials. As a result, strategies such as categorizing fit issue appearances, providing 3D visual examples with subcategorized causes, body types and parts could enhance quality of fit reviews and improve fit outcomes in clothing production systems.

• Environmental and Resource Economics Review
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• v.20 no.2
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• pp.335-356
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• 2011

In this paper, we attempted to suggest a way to evaluate appropriateness and efficiency for the energy consumption structure. For this, based on Markowitz (1952)' mean-variance portfolio model, we constructed an optimal fossil fuel mix. In constructing the optimal mix, we first defined returns on fossil fuels (oil, coal and natural gas) as TOE (Ton of Oil Equivalent) per $1. Then, by using the dynamic latent common factor model, we decomposed the growth rates of the returns on each fossil fuel into two parts : the common part and the idiosyncratic part. Finally, based on the results from the dynamic latent common factor model, we constructed the optimal fossil fuel mix implied by the mean-variance portfolio model. Our results indicate that for the fossil fuel mix to be on the efficient frontier, it is crucial to reduce oil consumption as low as possible. Moreover, our results imply that it is more efficient to increase natural gas consumption rather than coal consumption in reducing oil consumption. These results are in line with the strategies for the future energy consumption structure pursued by Korea and indicate that reduction in oil use can improve overall efficiency in energy consumption.

• Journal of the Korean Society for Railway
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• v.20 no.3
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• pp.349-355
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• 2017

Failures of railway systems can result in train delays or accidents, and therefore high reliability is required to ensure safety of railway systems. To improve reliability, railway systems are designed with redundant systems so that the standby system will continue to function normally even if the primary system fails. Generally, overall system reliability can be evaluated by the reliabilities of the parts of the whole system and the reliability of the redundant system considering common failures in case of each system is not conform physical, functional and process independent. In this study, the reliability of the hot-standby sparing system is analyzed the independent systems and dependent systems with common failures. The reliability for the standby system can be effectively analysed using Markov models, which can model the redundant configuration and the state transition.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5287-5291
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• 2013

The human papilloma virus (HPV) causes skin and mucous membrane infections. It crosses from one person to another by skin-to-skin contact, such as sexual contact. There are more than 100 types of HPV that can influence different parts of the body. Some types of HPV can cause cancer (such as cervical or anal cancer) and others can cause warts (such as genital or plantar warts). HPV infection is one of the most common sexually transmitted infections (STIs) in Iran and around the world. Considerable molecular evidence suggests a role for human papilloma virus (HPV) in the pathogenesis of carcinoma. Epidemiological studies on human papilloma viruses (HPVs) infections in general population are critical for the performing of health policy guidelines for developing the strategies to hinder the primary and secondary different cancer. In different parts of Iran, there is a lack of population-based studies to determine the prevalence of HPV in the general population. The aim of this population-based study was therefore to report the prevalence ratse of HPV types among Iranian patients. To study the risk of human papilloma virus (HPV) infection, we managed a retrospective study in Kerman province, southeast of Iran. For this purpose, 410 patients tested for the presence of HPV DNA using PCR and INNo-Lipa assays. HPV DNA was detected in 108 out of 410 patients (26.34%), while it was not detected in any of the control group samples. Patients included 23 (21.1%) males and 86 (78.8%) females. HPV type 6 was the most common (49%) followed by HPV type 16 (10.1%), and also HPV type11 (9.2%). The prevalence of HPV in Iran is comparable to those reported in other regions of the world. In a similar manner, it seems that HPV types 6, 16 and11 are the most common types in Kerman. Additional studies on larger group of patients, particularly in those with pre-invasive forms of disease, are needed to explain the roles of different HPV types in this location of Iran.

• BMB Reports
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• v.33 no.5
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• pp.417-421
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• 2000

Mitochondrial DNA (mtDNA) mutation was investigated in a hepatoma patient using a polymerase chain reaction (PCR) and an in situ hybridization technique. Biotin-labeled probes for the subunit m of cytochrome c oxidase revealed differences in the in situ hybridization. A PCR assay using biopsied and microdissected tissues showed that common deletion (4,977 bp) was more pronounced in the cancer region than in the normal parts of the same patient. These results suggest that mtDNA deletion might be associated with tumorigenesis in hepatoma.

• Journal of Korean Institute of Industrial Engineers
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• v.15 no.2
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• pp.77-86
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• 1989

A fully automated cost estimation system(FACES) has been developed. Since speed, accuracy, and consistency are essential factors in automating a cost estimation, the use of computers in cost estimation system(CES) has grown rapidly in the last few years. FACES is a micro computer based cost estimation system that employs a manufacturing knowledge base. A Group Technology(GT) based part classification and coding(C&C) scheme is used to automate the process planning aspects of cost estimation. Variant process planning methods are employed to generate workstation routings from form features of the part. The system has been tested for an assembly of six machined parts. Results indicate that the system could provide a substantial improvement in accuracy, productivity, and performance over the more traditional full dialog approach to cost estimation. It also provides a good foundation for a factory automation by using a common GT based database through design to production.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.9 no.4
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• pp.32-37
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• 2010

One of the most common engineering processes using plastics is the injection molding. In addition, plastics are utilized over the entire areas in our life including cars and home appliances among others for their characteristics with no deterioration even after a long time, as well as for their light weights in addition to their good durability. This paper aimed to minimize defects through prior analyses on the weld line, air traps, filling time, molding temperature and deformation patterns among others while carrying out interpretations on the cooling, filling and deformation in the injection process using the moldflow for rear lamp reflectors among components for a car in making parts through the coating process after injection.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.04a
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• pp.90-93
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• 2000

This paper presents job scheduling for non-identical parallel machines using Simulated Annealing (SA). The scheduling problem accounts for allotting work parts of L lots into M parallel machines, where each lot is composed of N homogeneous jobs. Some lots may have different jobs while every job within each lot has common due date. Each machine has its own performance and set up time according to the features of the machine, and also by job types. A meta-heuristic, SA, is applied in this study to determine the job sequences of the scheduling problem so as to minimize total tardiness of due. The SA method is compared with a conventional steepest descent(SD) algorithm that is a typical tool for finding local optimum. The comparison shows the SA is much better than the SD in terms tardiness while SA takes longer , but acceptable time.

• Journal of Auto-vehicle Safety Association
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• v.12 no.3
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• pp.27-33
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• 2020

In this paper, the process of predicting efficient durability performance for vibration durability test of automobile parts using vibration test load on automobile fuel tank is presented. First of all, the common standard load that can be applied to the initial development process of the automobile was used for the fuel tank and the vulnerability of the fuel tank to the vibration fatigue load was identified through frequency response analysis. In addition, the vulnerability of the fuel tank was re-enacted through vibration durability test results, and the scale factor was applied to the standard load. In order to predict the vibration durability performance required for detailed design, vibration fatigue analysis was performed on the developed vehicle with the frequency of vibration severity equivalent to the durability test, and the vulnerability and life span of the fuel tank were identified through the process of applying weights to these selected standard loads, thereby reducing the test time of the development vehicle.