• Proceedings of the Safety Management and Science Conference
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• 2002.05a
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• pp.275-283
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• 2002

This study is focused on the calculation for optimum period for environmental logistics system to replace old truck. Companies throughout the world have recognized the importance of environmentalism and the role of logistics in structuring a corporate response to environmental issues like recycling, waste disposal, pollution, and many others. Reverse logistics, the term often used to represent the role of logistics in environmentalism, is gaining acceptance by firms.

• Journal of the Korean Society of Safety
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• v.18 no.4
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• pp.35-38
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• 2003

The wire rope, one of the component of the elevator, is extremely important for the sage operation of the elevator. That is why the wire rope is replaced at a specific interval regradless of the operating conditions or the degree of damage to prevent the breakage of the wire rope. This is the waste of resources, causing economic and environmental loss. This paper has surveyed and analyzed and analyzed the status of replacing wire-rope by buildings that use elevators, in order to compare the replacement cycles of the wire rope under each operating conditions.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.05a
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• pp.1603-1608
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• 2006

Nuclear power plant have focused constituent that is always safety. However, period set to observe element that is economic performance keeping inner place now. Hereupon, in this study, chose fuel replace that is on one main activity doing at nuclear power plant for the target. And chose computerization and data management for fuel replace process to the direction.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.665-668
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• 2006

Concrete secondary product that use cement is increasing application from reason of shortening etc.. of construction period in construction site. Manufacture method of construction of this concrete secondary product there is hot-check method, direct spray method, press method, extrusion molding method etc.. Also, I am using reinforcement boating certainly in this process. In most case, We have used asbestos by reinforcement fiber until early 90s but use from human body hurtfulness controversy is felt constraint. Therefore, application of principal parts fiber is increasing. But, to replace asbestos, because must satisfy all lubricating ability, productivity etc.. class, it is the very difficult matter to replace asbestos. In this study, I wished to do Test about asbestos principal parts possibility at extrusion process to charge shape or form making test piece because mixs polypropylene fiber etc. by plan that replace asbestos in cement extrusion molding product and measures bending strength and elasticity.

• Journal of Animal Science and Technology
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• v.63 no.6
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• pp.1344-1354
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• 2021

This study was conducted to evaluate the effects of brown rice (Japonica) on growth performance, nutrient digestibility, and blood parameters of weanling pigs. A total of 60 weanling pigs (28-day-old, 30 barrows and 30 gilts, 6.73 ± 0.77 kg body weight [BW]) were randomly allotted to 2 dietary treatments (6 pigs per pen; 5 replicates per treatment) in a randomized complete block design with the initial BW and sex as blocks. The dietary treatments were a typical nursery diet based on corn and soybean meal (CON) and the CON replaced 50% of corn with brown rice (BR). Pigs were fed respective dietary treatments for 5 weeks. For the last week of experiment period, pigs were fed respective dietary treatments containing 0.2% chromic oxide as an indigestible marker. Fecal samples were collected from randomly selected 1 pig in each pen daily for the last 3 d after the 4-d adjustment period. Blood was collected from randomly selected 1 pig in each pen on d 0, 3, 7, and 14 after weaning. Compared with pig fed CON diet, pigs fed the BR diet were found to have higher (p < 0.05) final BW, overall average daily gain, and apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of dry matter and energy. However, there were no significant differences between the groups with respect to average daily feed intake, gain to feed ratio, frequency of diarrhea, and the AID and ATTD of crude protein during overall experimental period. Similarly, there were no significant differences on blood parameters between the groups. Thus, the findings of this study indicate that brown rice (Japonica) can be used to replace 50% of corn in the diet of pigs during the nursery period without negatively affecting growth performance, nutrient digestibility, or blood parameters.

• Earthquakes and Structures
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• v.13 no.3
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• pp.231-239
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• 2017

Fundamental period is one of the most critical parameters affecting the seismic design of buildings. In this paper, a very simple approach is presented for estimating the fundamental period of multiple-degree-of-freedom (MDOF) structures. The basic idea behind this approach is to replace the complicated MDOF system with an equivalent single-degree-of-freedom (SDOF) system. To realize this equivalence, a procedure for replacing a two-degree-of-freedom (2-DOF) system with an SDOF system, known as a two-to-single (TTS) procedure, is developed first; then, using the TTS procedure successively, an MDOF system is replaced with an equivalent SDOF system. The proposed approach is expressed in terms of mass, stiffness, and number of stories, without mode shape or any other parameters; thus, it is a very simple method. The accuracy of the proposed method is investigated by estimating the fundamental periods of many MDOF models; it is found that the results obtained by the proposed method agree very well with those obtained by eigenvalue analysis.

• Journal of Korean Society for Quality Management
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• v.28 no.1
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• pp.210-219
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• 2000

When an electronic control system has been used for long time, the electronic control system becomes obsolete and no longer In production. In this case, the existing control system should replace by new system due to shortage of spare modules. However, if the proper number of spare modules are stocked, it may be possible and more economical than to replace by new system to extend the usage period of the existing control system. In this case, it is an important problem to determine the proper number of spare modules. In this paper, a method to determine the proper number of spare modules is presented with an application example.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.126-127
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• 2014

At construction sites, due to the reason of inconvenience and difficulties of producing and using curing equipment and when it comes to measuring compression strength of the actual structure, strength of structure concrete according to general standards which are suggested in concrete standard specification are assessed. However, this method does not consider various variables of the sites such as kinds concretes and sizes of frame works so that it is not easy to measure proper curing period and strength. Thus, this study reviews description of strength development according to In-situ temperature system and analyzes and compares properties of strength development of the existing curing methods such as sealing curing so that it provides basic materials for period of removal of molds.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.2
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• pp.1-13
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• 2021

Previous studies have found the significant adverse effects of coronavirus disease 2019 (COVID-19) on stock returns and volatility. The effects varied with the confirmed cases and deaths. However, the extent of the effects have never been measured exactly. This study proposes a measurement model for the COVID-19 effects. In the proposed model, stock returns in the COVID-19 period are weighted averages of pre-COVID-19 normal returns and COVID-19-induced returns. The effects are measured by the contributing weights of the COVID-19-induced returns. Kalman filtering is used to estimate the model for the world and Chinese markets, in combination with 10 markets - five most affected countries (United States, India, Brazil, Russia, and France) and five best recovering countries (Hong Kong, Australia, Singapore, Thailand, and South Korea). The sample returns are daily, obtained from the closing Morgan Stanley global investable market indexes. The full period is from September 24, 2018, to October 30, 2020, whereas the COVID-19 period is from November 18, 2019, to October 30, 2020. The contributing weights are significant and close to 100% for all markets. The COVID-19-induced returns replace the pre-COVID-19 normal returns; they are negatively auto-correlated and highly volatile. The COVID-19-induced returns are new normal returns in the COVID-19 period.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.9
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• pp.1764-1768
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• 2009

As the demand of electric power is increasing rapidly, the need of the compact and light electric power device is also increased. Copper clad aluminum (CCA) is newly proposed electrical conductor, because of its light-weight and low-cost characteristics, to replace the existing conductor made of copper. This paper presents the salt-proof characteristics of the copper clad aluminum (CCA) to certificate long time safe operation of the newly proposed electrical conductor. The two types of the CCA conductor were tested in the neutral salt spray tester. The experimental results of two types of the CCA with salt spray were presented in this paper. The results comprise resistance measured data, micro picture of the selected surface, and component measured data according to the elapsed time. The period of the experiment was 1,000 hours. There was no evidence to show the corrosion of CCA during the whole period of the experiments.