• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.419-431
• /
• 2007

The track and rail surface geometry is of prime importance on the requirement for track dynamic stiffness, particularly for the speed of 350 km/h, for which both the requirement for fatigue and tensile strength limits require a lower stiffness than 100 kN/mm, which is near the value for ballasted track. However, the track quality has been considered as being the same for 350 km/h as that for 300 km/h, and based on ballasted track, and the track geometry may be kept in better condition with a slab track(probably more similar to the medium quality track geometry of ballasted track). In conclusion, under the condition that the track geometry quality provided by the concrete slab system is fairly good, and that the required maintenance is applied to the rail surface, there would be no safety risk if the fastening system point stiffness reaches 160 kN/mm for 300 km/h operation, and 110 N/mm at 350 km/h.

• Journal of the Korean Society of Tobacco Science
• /
• v.14 no.1
• /
• pp.57-65
• /
• 1992

The quality of cut tobacco will be deteriorated due to weather conditions such as temperature and relative humidity, when shipping and long term storaging. The change of equilibrium moisture contents in cut tobacco were under influence of relative humidity and temperature but not humectants. Therefore internal packing materials are necessary for cut tobacco to maintain initial quality, including taste, flavour and musty smell during shipping or storaging. When packing cut tobacco for shipping or long term storaging, desiralbe packing density was 200/$m^2$, For the long term storage under R.H 90% and 3$0^{\circ}C$, polyethylene film thickness suitable for packing material are above 100$\mu$, which resulted in 42days of shelf life.

• Journal of Korean Society for Quality Management
• /
• v.38 no.3
• /
• pp.449-462
• /
• 2010

In this Paper, We analyzed influence Factor to TPM Performance in medium and small enterprises by empirically. By Literature survey, We hypothesize education training and 5S influence to individual improvement, independence maintenance, planning and foresight, which also influence to flexibility, total equipment performance, quality, which finally influence to lower cost, delivery date. To analyze empirically, we survey questionnaire in medium and small enterprises being below 300 people. From statistical analysis, 7 hypotheses are rejected, which is different existing research. This is analyzed that reflect actuality that medium and small enterprises is different from large enterprises. We expect that result of this treatise does concentration effort in important factor to get TPM performance in medium and small enterprises.

• Journal of Korean Society for Quality Management
• /
• v.41 no.3
• /
• pp.413-421
• /
• 2013

Purpose: System availability and life cycle cost are often used to evaluate the system performance and is influenced by the operation and maintenance characteristic. In this paper, we propose the method to improve life cycle cost and satisfy the target availability through redundancy allocation. Methods: We consider the redundancy is available at all items in multi level system. Thus, we assume that sub-assembly, module, components can be duplicated. Simulation and genetic algorithm are employed to optimize redundancy allocation. Results: Target availability is higher, the life cycle cost is increased. In addition, the items for redundancy are selected at higher level in multi level system if target availability is higher. Conclusion: We could know that target availability affects the duplication number of items and the selection of redundancy items. For further study, we will consider new optimization algorithms to compare with the proposed GA algorithm and improve optimization performance.

• Proceedings of the Membrane Society of Korea Conference
• /
• 1995.10a
• /
• pp.106-122
• /
• 1995

Industrialization has given humanity many benefits, such as material abundance and conveniences. However, it has also caused detrimental side effects to the environment which are becoming a global problem. During the 1960's, the national economic scale in Korea was expanded and personal lifestyles rapidly improved. These improvements also caused environmental problems such as water contamination. Water contamination caused by old, worn water pipes, harmful materials and deposits from the water purification processes decreased the tap water quality, causing unpleasant odors and tastes. Due to poor maintenance of the reservoir facilities of tap water quality, citizens lost their faith in the water quality. In the long term, it made us worry about the health of our nation's citizens (6,16).

• Journal of Korea Technology Innovation Society
• /
• v.2 no.1
• /
• pp.74-89
• /
• 1999

The purpose of this study is to identify in two aspects the relationship between standardization activities and technological development at the firm level. The first aspect is to analyze the relationship between the current Korean industrial standards system and the firm's technological development vis-a-vis quality standards. The analysis reveals that even if Korean firms recognize the importance of standards, the level of product quality of the KS mark is still lower compared to the average world level. The survey also reveals that the reasons for acquiring ISO and KS marks are mainly aimed at enforcing company image and increasing quality management mind, rather than to foster technological innovation. The second aspect explores how much Korean industrial standards (KS marks) affect the firm's technological development in the Process of standards acquisition activities. The survey results show that standardization activities have a less positive impact on technological innovation than on the maintenance of consistent production works.

• Journal of the Korean Society of Food Culture
• /
• v.21 no.1
• /
• pp.51-56
• /
• 2006

This research suggests critical and specific decisive variables that affect general service quality of the products in family restaurants, considering features of services in which consumption and production happens simultaneous by collecting the raw data through point of sales. It also analyses the factors and helps to offer them practical strategies by providing managers of the restaurants and marketers with empirical viewpoints based on the research. Generally, family restaurants need their own physical environment and are required to encourage customers to revisit themselves by maintaining pleasant environment as well as, considering space for customers and for employees' working routes and effective maintenance of the facilities. The result of the study also tells that even if the unimportant factors did not affect much on the restaurants, management over these factors can be a differentiated strategy for competitive advantage over the other businesses.

• The Transactions of the Korea Information Processing Society
• /
• v.2 no.6
• /
• pp.918-926
• /
• 1995

In this paper, we study on the systems management for managing ATM network which is especially related to the management of Quality of Service(QoS). QoS management is considered as monitoring function. Therefore, we establish the management model of control and information aspects to manage ATM layer which has resource control, Operation and Maintenance (OAM) functions for performance management and monitoring functions. In particular, we focus on the effective processing of reported performance information caused by the indication of QoS degradation being represented as "QoSAlarm". In order to perform these management activities, the manager can process problem reports of QoS degradation in the proposed manner which uses the priority concepts based on QoS classes. In this circumstance, it is possible to take recovery actions in a predetermined and limited time for managed objects with fault and performance problems.

• Journal of Food Hygiene and Safety
• /
• v.35 no.3
• /
• pp.205-212
• /
• 2020

Foodborne diseases occur frequently and have various being related to the intake of contaminated foods. Seafood products are susceptible to contamination due to higher water content and microorganisms, which combine to give them a short shelf-life. Various approaches have been applied to overcome this problem. Edible coatings that are also biodegradable and biocompatible have been discussed as one of the applicable solutions. These coatings can actually help to maintain seafood quality by inhibiting the growth of microorganisms and delaying the loss of moisture. This paper presents the effects of various natural bio-polymers, antimicrobial substances and physical sterilization techniques such as gamma irradiation, ultraviolet (UV) sterilization, and light-emitting diode (LED) sterilization on seafood coatings.

• Journal of Korean Society of Water and Wastewater
• /
• v.29 no.4
• /
• pp.493-502
• /
• 2015

In accordance with the Watershed Sewer System Maintenance Plan enforced on February 2, 2013, the different compliance concentration of effluent limit be applied to effluent discharged from public sewage treatment works(PSTWs) in each watershed on the basis of water quality thereof. With the introduction of watershed sewer system, it is necessary to set the compliance concentration of effluent limit for PSTWs situated in the watershed, by region and PSTW size, to achieve water quality criteria for regional watersheds or target water quality under TMDL program. Watershed Environmental Agencies establish the Watershed Sewer System Maintenance Plan and set the compliance concentrations of effluent limit for PSTWs under the plan. The agencies plan to apply tougher effluent BOD concentration limits in Class I to IV areas. Effluent BOD concentration limits will be toughened from 5~10 mg/L to 3 mg/L in class II~III areas, from 10mg/L to 5mg/L in class IV areas. Uniform application of effluent BOD concentration limits to PSTWs in the watershed sewer system need to be complemented considering type of sewage treatment technology employed and watershed characteristics. Therefore, this study presents method to determine the compliance concentration of effluent limit from PSTWs in the watershed.