• Journal of Applied Reliability
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• v.17 no.2
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• pp.103-111
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• 2017

Purpose: Accelerated degradation tests can speed time to market and reduce the test time and costs associated with long term reliability tests to verify the required service life of a product or material. This paper proposes a service life prediction method for components or materials using an accelerated degradation tests based on the relationships between temperature and the rate of failure-causing chemical reaction. Methods: The relationship between performance degradation and the rate of a failure-causing chemical reaction is assumed and least square estimation is used to estimate model parameters from the degradation model. Results: Methods of obtaining acceleration factors and predicting service life using the degradation model are presented and a numerical example is provided. Conclusion: Service life prediction of a component or material is possible at an early stage of the degradation test by using the proposed method.

• Toxicological Research
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• v.9 no.1
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• pp.69-72
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• 1993

LBD-005, a newly developed recombinant granulocyte-macrophage colony stimulating factor, was tested for primary skin irritation in male New Zealand White rabbits. In the primary skin irritation test, LBD-005 was applied to intact and abraded skins for 24 hours. Primary irritation index was "0" in test and control sites of all animals' thus LBD-005 was evaluated as a non-irritatant on the basis of the criteria of Draize et al. (1994).l. (1994).

• Advances in concrete construction
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• v.7 no.3
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• pp.191-201
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• 2019

Bamboo concrete bond behaviour is investigated through pullout test in this work. The bamboo strip to be used as reinforcement inside concrete is first treated with chemical adhesive to make the bamboo surface impermeable. Various surface coatings are explored to understand their water repellant properties. The chemical action at the bamboo concrete interface is studied through different chemical coatings, sand blasting, and steel wire wrapping treatment. Whereas mechanical action at the bamboo concrete interface is studied by developing mechanical interlock. The result of pullout tests revealed a unique combination of surface treatment and grooved bamboo profile. This combination of surface treatment and a grooved bamboo profile together enhances the strength of bond. Performance of a newly developed grooved bamboo strip is verified against equivalent plain rectangular bamboo strip. The test results show that the proposed grooved bamboo reinforcement, when treated, shows highest bond strength compared to treated plain, untreated plain and untreated grooved bamboo reinforcement. Also, it is observed that bond strength is majorly influenced by the type of surface treatment, size and spacing of groove. The changes in bamboo-concrete bond behavior are observed during the experimentation.

• Korean Journal of Pharmacognosy
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• v.22 no.2
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• pp.124-127
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• 1991

In the preceding paper, it was reported that total 63 traditional Korean herbal medicines listed in the Korean Pharmacopoeia and Korean Natural Drug Standards were found to be different plants in terms of systematic botany when those were compared with other two countries' drug compendia, Chinese Pharmacopoeia, Japanese Pharmacopoeia and Japanese Natural Drug Standards. Among 63 traditional Korean herbal drugs, 28 items were subject to the chemical identification test by using official methods that are described in the Korean Pharmacopoeia and the Korean Natural Drug Standards. In addition, 5 items were also tested by using the official methods described in Chinese and Japanese drug compendia, since there are no official chemical tests available in the Korean drug compendia. It was found that most of chemical tests appeared to be suitable. It was noted that the chemical test for Atractylodis Rhizoma(蒼朮) was incorrect and unapplicable. Those chemical tests for Clematidis Radix(威靈仙), Rubi Fructus(覆盆子) and Viticis Fructus(蔓荊子) are desirable to be revised for more accurate identification.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.4
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• pp.387-394
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• 2015

We have recently developed a cost-effective and pouch-type chemical vapor sampler which consists of a selectively permeable high density polyethylene(HDPE) membrane, aluminum/nylon barrier film, and adsorbents. Since the sampler mimics the actual adsorption process that occurs when the skin is exposed to chemical vapors, it can be applied to man-in-simulant test(MIST) to determine the protective capability of individual protective ensembles for chemical warfare agents. In this study, we describe the manufacturing process of samplers and results for performance testing on MIST. Methyl salicylate(MeS) is used to simulate chemical agent vapor and the vapor sampler was used to monitor chemical concentration of MeS inside the protective suit system while worn. Values of protection factors(PF) were also analyzed to provide an indication of the protection level of the suit system evaluate by MIST. The results obtained by home-made samplers(ADD samplers) and commercially avaliable ones(Natick samplers) showed no significant differences.

• The Korean Journal of Pesticide Science
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• v.9 no.1
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• pp.41-50
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• 2005

For the removal of residual pesticides in ginseng extracts, we estabilished the removal process using pilot plant system, the characteristic components of ginseng maintains only. According to the agricultural chemical removal process, we monitored residual pesticides of 155 species, compraing the characteristic components of ginseng. The process of 4 types of agricultural chemical removal process compared to the control test was appeared that the residual pesticides were eliminated. As results above, the most efficient method of the possibility of raising the removal ratio of the agricultural chemical construction process was dried process of hexane after dipping and also remaining quality of the hexane appeared lowly. Besides, the removal process had an effected on the ginsenocide os ginseng, only the residual pesticides will be able to remove.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2001.11a
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• pp.98-98
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• 2001

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.1
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• pp.129-134
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• 2014

We have developed a cost-effective and facile method to manufacture a pouch-type chemical vapor sampler. Originally, the sampler was developed by U. S. Army Natick Soldier Research, Development, and Engineering Center(NSRDEC) to determine the protective capability of individual protective ensembles or Man-in-Simulant Test (MIST). They used a selectively permeable high density polyethylene(HDPE) as front membrane and aluminum/ Nylon barrier film as an impermeable back sheet in order to mimic the actual adsorption process that occurs when the skin is exposed to chemical weapons. However, it costs over twenty dollars per sampler and the minimum of quantity is 2500 per order. In addition, it is inconvenient to employ a variety of adsorbents into the sampler, which could prevent MIST researchers to do various tests for development of MIST methodologies. Here, we report the simple method to manufacture the sampler in a laboratory scale. All the materials we used are easily obtainable and inexpensive. In addition, all the procedures we perform are generally known. We used methyl salicylate(MeS) vapor to be adsorbed into the sampler and employed several different adsorbents to evaluate the performance of samplers. The results obtained by home-made samplers and commercially avaliable one showed no significant differences. Also, MeS vapor was selectively adsorbed into the sampler depending on adsorbents. We conclude that home-made samplers are capable of collecting any kind of chemical vapor for a variety of purposes.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.196-199
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• 2004

Metakaolin is a cementitious material for producing high-strength concrete. This material is now used as substitute for silica-fume. In this paper, we tested the compressive strength of concrete according to the substitute ratio of metakaolin, silica-fume. And we did the durability test such as chloride ion diffusion and chemical attack. In the compressive strength test, the result shows that $10\%$ substitute of metakaolin & silica-fume for binder is optimum. In the chloride ion diffusion test, according to the increase of substitute of metakaolin & silica-fume for binder, the diffusion coefficient is more reduced. And in the chemical attack test, according to the increase of substitute, the resistance is more excellent. In the durability test, we recognized that metakaolin is able to used as a substitute for silica-fume.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.495-498
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• 2005

It was investigated the durability of the concrete to improve construction materials with polymer cement mortar in this study. With the popularity of repair and rehabilitation material, some mixtures composed of Ethylene Vinyl Acetate(EVA) was studied. Ethylene Vinyl Acetate(EVA) carried out tests to determine its properties which a include: freezing-thawing resistance test, carbonation test, and chemical resistance test. Result of freezing-thawing resistance test, mass change ratio and chemical resistance test, mass change ratio decreased of 12 and $15\~45\%$ as compared with control mortar. Carbonation depth decreased $3.7\~5.6mm$ as polymer-cement ratio increased $1\~4\%$.