• Journal of the Korea Safety Management & Science
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• v.13 no.3
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• pp.1-8
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• 2011

The overall goal of a safety based railroad system is either to eliminate hazards in designing or to minimize the possibility of it. In order to indicate system safety or low risk although it may not be possible to achieve zero risk conditions, first, it shall ensure that any disasters would occur due to system operation because the prescribed specifications are properly fulfilled and there are no failures of any kind. Second, the risk of faults or failures leading to a mishap must be eliminated or minimized by using fault-tolerance or fail-safe procedures. This paper will attempt to summarize the personal and social risk criterion at widely scattered points, presently used as a safety approach in all over EU, in order to establish the step by step procedures of the detailed standard for railway facilities. In addition, we present the new safety analysis method using the SIL-based evaluation standard and the Reachability Graph of the Petri Net.

• Journal of Korean Society for Quality Management
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• v.44 no.1
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• pp.77-94
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• 2016

Purpose: This paper reviews Type 1 Gage study, Gage R&R study, and procedure of ISO 22514-7 for assessing a measurement system, and discusses some relationships between the measurement capability indices. Methods: The gage capability index $C_g$ of Type 1 Gage study, precision-to-tolerance ratio PTR of Gage R&R study, and measurement performance ratio $Q_{MS}$ and $Q_{MP}$ of ISO 22514-7 are considered in this paper. Results: This paper derives the relationships between $C_g$ and $Q_{MS}$, PTR and $Q_{MP}$, and $Q_{MS}$ and $Q_{MP}$, respectively, and discusses the acceptance conditions for each procedures. Conclusion: The measurement capability analysis is the first step for the quality improvement of the manufacturing processes. Therefore the result of this study provides a helpful guidelines for assessing the measurement system, enabling proper evaluation of manufacturing processes.

• Korean Journal of Organic Agriculture
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• v.31 no.4
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• pp.309-325
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• 2023

GMO labeling system in South Korea stipulates three labeling methods: GMO labeling, no labeling and Non-GMO labeling. Products labeled as Non-GMO are not allowed for unintentional commingling of GMO without tolerance. However, consumers vary their acceptance of Non-GMO label on the unintentionally commingled products and willingness to pay according to the mixing rate, rather than devalue the whole products as useless. Additionally, consumers do not believe that the acceptable mixing rate should be discriminated between non-labeled products, which allow up to 3% of unintentional GMO contamination, and Non-GMO labeled products. Information on unintentional GMO mixing mainly refers to the mixing rate, but the Non-GMO content remaining even after commingling is also important information. The decline in value is alleviated when consumers are exposed to positive information, such as Non-GMO content, rather than when exposed to negative information, such as the mixing rate. Loss Aversion Coefficient is relative depending on whether the information representing the loss is positive or negative. Information that a Non-GMO labeled product contains X% GMO is more sensitive than information that (100-X)% Non-GMO remains.

• Culinary science and hospitality research
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• v.20 no.4
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• pp.310-321
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• 2014

This study investigated the effects of starches(potato, sweet potato, and corn starch) on the quality characteristics of raw and cooked noodles. The moisture content, color, mixogram, texture profile and sensory evaluation were performed. The mixogram showed the addition of starches shortened the kneading time. Mixing tolerance was higher in the noodles with starch than the control group, which indicates that the addition of starch increases dough durability. Moisture content of raw noodles was the highest in the samples with potato starch. L-value of raw noodles was the highest in the samples added with corn starch, whereas that of cooked noodles was the highest in the samples added with potato starch. The hardness of raw noodles was the highest in the control sample, and the chewiness of raw noodles was the highest in the samples added with sweet potato starch. The hardness of cooked noodles was the highest in the samples added with corn starch and the lowest in the control group. The tension distance of raw noodles was the longest in the control group and the tension force of raw noodles was the highest in the noodle with sweet potato starch. The acceptance test indicated that the noodles prepared with the addition of sweet potato starch scored the highest in flavor, taste, texture and overall acceptability.

• Journal of the Korean association of regional geographers
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• v.23 no.1
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• pp.23-46
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• 2017

This article examines the sexualization of place under conditions of the compressed modernization and reflexive cosmopolitanism. In particular, I adopt Michel de Certeau's spatial didactic model of strategy and tactic to investigate the dynamics at play in the gay labelling of a Coffee Bean & Tea Leaf (Coffee Bean) in South Korea, and explore the 'gaying' that takes place within preconceived heteronormative space. Using interview data, I additionally explore the negotiation tactics and coping mechanisms at work when gays compete with heterosexuals for non-gay place. The results illustrate how gays gay in heteronormative space and how heteronormative space harmoniously embodies gay men. The findings suggest that spatial location and tactic play important roles in stimulating compromise of sexual territory. Gay Bean benefits from being nestled between locations with histories of tolerance, while it also prospers from reflexive cosmopolitan ideals of diversity and acceptance of others. Gay identity and gaying is interpreted as foreign in Korea, which buttresses gay performativity in spaces welcoming of foreigners and so-called "deviance." However, how gaying functions within place relies not only on spatial histories of tolerance outside, but also on the tactics of identity negotiation within. The findings suggest that spatial and tactical conditions induce gay individuals to police other gay-identified individuals when gays gay in so-called heteronormative places.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.3
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• pp.145-153
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• 2016

Cable TV with largest subscription base in pay TV market has difficulty in managing the task of digital switch over. This study analyzed the factors in delay of cable TV switch over and examined the impact of pay TV market structure and competition. The delaying factors turned out to be the lack of incentives and resources of cable TV operators, insufficient policy measures and acceptance tolerance issues of subscribers. Since cable TV operators with monopolistic status in pay TV market had continuous profit from analog service, they were not responsive to digital switch over which requires additional investment. Policy measures including support for the low income household and mandatory cut-off point for stopping analog broadcasting. Subscriber's willingness to accept digital broadcasting in terms of price sensitivity and preference for convenient operation also played a role. Introduction of IPTV in pay TV market influenced the speed of digital switch over of cable TV operators. MSOs with economies of scale showed higher digital switch over rate than independent SO.

• Archives of Reconstructive Microsurgery
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• v.18 no.1
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• pp.9-15
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• 2009

Whether a seven days course of anti-${\alpha}{\beta}$-T cell receptor-antibody (${\alpha}{\beta}$-TCRmAb) combined with FK506 therapy promotes survival of limb allografts in fully MHC-mismatched combination (Brown Norway $\rightarrow$ Lewis) was examined. Eight animals received 250 ${\mu}g$/kg/day of ${\alpha}{\beta}$-TCRmAb for 7 days and 2 mg/kg/day of FK506 postoperatively (Combination therapy group). Eight animals had FK506 only (Mono-therapy group) and five animals did not have treatment (Control group). Clinical signs of early rejection with edema or erythema in the skin occurred at an average of 8.6${\pm}$1.5 days postoperatively in Control group and 59.0${\pm}$8.3 days in Mono-therapy group, both of which proceeded to irreversible rejection with necrosis of the epidermis and finally mummification. In Combination therapy group, all animals showed evidence of early rejection at an average of 56.8${\pm}$12.6 days postoperatively, however, in 4 of 8 limbs, early rejection resolved without any treatment and limbs survived >1 year. At 9 months postoperatively, donor skin grafts were accepted and third-party skin grafts were rejected by all four survivors, demonstrating donor-specific tolerance. Little or no detectable chimerism was observed in any of the 4 surviving animals at one-year postoperatively. Combination therapy of ${\alpha}{\beta}$-TCRmAb and FK506 resulted in long-term survival in fully MHC-mismatched limb transplants.

• Journal of radiological science and technology
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• v.43 no.2
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• pp.105-114
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• 2020

This study aimed to assess of beam-matching accuracy for an 8 MV beam between the same model linear accelerators(Linac) commissioned over two years. Two models were got the customer acceptance procedure(CAP) criteria. For commissioning data for beam-matched linacs, the percentage depth doses(PDDs), beam profiles, output factors, multi-leaf collimator(MLC) leaf transmission factors, and the dosimetric leaf gap(DLG) were compared. In addition, the accuracy of beam matching was verified at phantom and patient levels. At phantom level, the point doses specified in TG-53 and TG-119 were compared to evaluate the accuracy of beam modelling. At patient level, the dose volume histogram(DVH) parameters and the delivery accuracy are evaluated on volumetric modulated arc therapy(VMAT) plan for 40 patients that included 20 lung and 20 brain cases. Ionization depth curve and dose profiles obtained in CAP showed a good level for beam matching between both Linacs. The variations in commissioning beam data, such as PDDs, beam profiles, output factors, TF, and DLG were all less than 1%. For the treatment plans of brain tumor and lung cancer, the average and maximum differences in evaluated DVH parameters for the planning target volume(PTV) and the organs at risk(OARs) were within 0.30% and 1.30%. Furthermore, all gamma passing rates for both beam-matched Linacs were higher than 98% for the 2%/2 mm criteria and 99% for the 2%/3 mm criteria. The overall variations in the beam data, as well as tests at phantom and patient levels remains all within the tolerance (1% difference) of clinical acceptability between beam-matched Linacs. Thus, we found an excellent dosimetric agreement to 8 MV beam characteristics for the same model Linacs.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.1
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• pp.31-40
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• 2022

Six Sigma is a philosophy and systematic methodology for quality improvement. It encourages continuous quality improvement efforts to achieve the ideal goal of 6σ. Sigma(σ) is a statistic representing the standard deviation of the normal distribution, and 6σ level means a level where the tolerance of the specification is six times the standard deviation of the process distribution. In terms of the defective rate, the 6σ level achieves the 0.002 defectives per one million units. However, in the field, the 6σ level is used in the sense of achieving 3.4 defects per one million opportunities, which shows a large gap from the 6σ level in the statistical viewpoint. This is because field practitioners accept a 1.5σ shift of the mean of process when calculating the defective rate under sigma level. It said that the acceptance of 1.5σ shift of the mean is from experience, but there is no research or theoretical explanation to support it logically. Although it is a non-scientific explanation based on experience, considering that there has been no objection to the 1.5σ shift for a long time and it is rather accepted, it is judged that there is a reasonable basis for the 1.5σ shift. Therefore, this study tries to find a reasonable explanation through detective power of control chart via the run-rules to the 1.5σ shift empirically recognized by practitioners.

• Journal of Korean Society of Steel Construction
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• v.26 no.6
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• pp.511-522
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• 2014

In this study, an innovative steel stair system is presented which enables rapid erection and high quality control in both residential and office building construction. This system features two lightweight steel stringers of box shape, bolted connections easy to absorb construction tolerance, and stair steps movable transversely (or sliding steps) such that the work space needed for concrete stairway wall could be easily provided. In this type of stairway system, other than providing robust connecting details, ensuring vibration performance is especially important since this system may be vibration-sensitive due to lightweight nature and/or probable low damping. To tackle these issues, a series of full-scale mock-up tests were conducted by using box-shape stringer members with or without concrete-fill. The connection system was shown to be sufficiently stiff and strong, or it remained elastic even under the 160% of service load level. Among the seven stringer alternatives, five exhibited satisfactory vibration performance according to the related North American and European acceptance criteria.