• Journal of Korean Society of Environmental Engineers
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• v.32 no.6
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• pp.625-630
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• 2010

This study aims to examine the possible use of heavy oil fly ash as raw material for deodorization panels by adding additives such as activated carbon and diatomite during deodorization panel manufacturing process and improving the performance of formaldehyde and toluene elimination.The recycled heavy oil flyash deodorization panel to be used either of them as additives removed more than 93% of formaldehyde and more than 97% of toluen but the compressive strength was decreased 27 to 63%. In an experiment to be used both additives, Whereas, the panel to include activated carbon 5% and diatomite 5% removed 84% against formaldehyde and 96% against toluen, and the compressive strength was increased 32% better than standard panel. Therefore it could be confirmed that the recycled heavy oil flyash deodorization panel is increased the compressive strength and the removal efficiency against harmful chemical substances by using the additives mixture.

• Journal of Korea Technology Innovation Society
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• v.19 no.4
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• pp.736-767
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• 2016

Recently, the social issue about harmful effects of nano-materials including nano-products to human body and environment have been raised, which were not expected in times past. To prevent the risks of nano-materials on the environment and human body, the regulatory policies are reinforced to ensure public health in world trends. In Korea, governmental department has prepared the policy for 'National nano-safety Management Master Plan' since 2011. However, it is very hard to manage all kinds of nano-materials, due to lack of nano-safety law and a wide range of nano-technology application. This study aims to analyze the current situation of the national policy related to nano-safety management and legislation, and also review the limitation of current system to propose improvement plan for nano-safety.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.6 no.1
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• pp.10-17
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• 1997

It is pointed out that the color of composite resin is changing according to it's ploymerization and this color change is a harmful effect for the clinical satisfacion of composite resin restoration. The purpose of this study was to compare the changes of color of newly developed composite resins between before and after exposure of activating light. Five Compostie resins (8 shades) were employed: Palfique Estelite(UL, U, DY, G ; Tokuyama), Photo Clearfil A (US : Kuraray), Photo Clearfil Bright (US ; Kuraray), GC Graft LC(A3 ; GC), Silux Plus(U; 3M), Tristirnulus values of each material were determined before and after curing-light exposure by using a Micro Multi Photometer (MMP-1001, Nihon Denshoku Kogyo). The values were transformed into $L^*\;a^*\;b^*$ system and color changes of the resins were evaluated by the changes of $L^*$, $a^*$ and $b^*$ values for the individual shades. In addition, the effects of resin thickness and background color on color changes were also studied The finding were as follows: 1. Color changes of $L^*$, $a^*$ and $b^*$ values were recognized due to the light exposure for all products. The $b^*$ values of Palfique Estelite showed negligible changes for all shades. 2. The $b^*$ values were affected strongly by the background color, especially when decreasing the brightness on the background color.(Request original article reprints to Dr. Aoshima)

• Clinical and Experimental Reproductive Medicine
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• v.28 no.4
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• pp.295-300
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• 2001

Objective : To assess the effects of progesterone and acetyl-L-carnitine used after treated with Isolate�� gradient before semen cryopreservation-thawing on sperm parameters and membrane integrity. Material and Methods : From April 2001 to July 2001, ten normal male partner of couples who were visited in vitro fertilization (IVF) clinics. the semens were treated with $Isolate^{(R)}$ gradient before cryopreservation, spermatozoa was incubated with progesterone (1, 5 and $10{\mu}M$), acetyl-L-carnitine (2.5, 5 and $10{\mu}M$), or both (progesterone, $1{\mu}M$; and acetyl-L-carnitine, $5{\mu}M$) for 30 min. Results: There were no differences in sperm parameters and vital stain among isolate only treated group, progesterone (1, 5 and $10{\mu}M$), acetyl-L-carnitine (2.5, 5 and $10{\mu}M$) and both (progesterone, $1{\mu}M$; and acetyl-L-carnitine, $5{\mu}M$). But, in high concentration of acetyl-L-carnitine ($10{\mu}M$) treated group, sperm parameters and vital stain were decreased. The statistical method was used ANOVA (Kruskal-Wallis test) and p value was <0.01. Conclusions : Neither progesterone nor acetyl-L-carnitine show to be protective effect on the cryodamage assessed by sperm parameters and vital stain (eosin-Y stain) in normal sperm. High concentration of acetyl-L-carnitine ($10{\mu}M$), however, was harmful effect on cryoprevention.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.629-632
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• 2008

As concrete is a material which is subject to wide quality fluctuations by temperature, grip of seasonal feature and maintenance of ambient temperature and humidity to secure the quality required after casting concrete are able to keep away from harmful effects. In case of summer, a high temperature has caused rapid hydration reaction of cement in early age, which has caused to decrease strength by autogenous shrinkage. Therefore we need to consider a countermeasure for decrease in the hydration heat of hot-weather concrete, according to minimize water and cement content and use mineral admixtures In this experimental research, the compressive strength development for replacement ratio of mineral admixtures, curing temperature and methods of concrete was investigated to confirm the effects of mixture design and curing condition on compressive strength of concrete.

• Journal of the Korea Concrete Institute
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• v.28 no.1
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• pp.49-57
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• 2016

The aim of this study was to investigate the fundamental properties of pyroclastic flow deposit (PFD), and evaluate the fresh and strength properties of concrete mixed with PFD by indoor tests. The fresh properties, strength properties, shrinkage properties, and durability of the concrete mixed with PFD were also evaluated by outdoor plant tests. the harmful alkali-silica reaction did not occur by mixing concrete with PFD. ages. Moreover, no difficulty was found to be associated with concrete manufacture in the plant because no change in air contents and noticeable slump loss occurred by mixing concrete with PFD. The strength properties, shrinkage properties, and durability of the concrete mixed with PFD were also compared with those of normal concrete. With a suitable temperature control and curing method of concrete, the concrete mixed with PFD is considered to be useful in the construction material field.

• Fashion & Textile Research Journal
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• v.10 no.5
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• pp.702-712
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• 2008

The aim of this study is to develop Casual Hanbok design made of Hanji yarn textiles for New Silver generation women. The New silver generation is a coined word which has meaning of a newly silver generation and it is distinguished from pre-silver generation. New silver generation is a generation that is independent and given active role by their age groups and generational characteristic. The concept of silver generation was introduced from maturity market in Japan. This study was based on analysis about their preference of forms, colors, and materials of Casual Hanbok. The survey target were 270 female over age 50 living in Daejeon City. The analysis methods used frequency and percentage. The results were summarized as following. Although almost of them haven't worn Casual Hanbok, they had the positive recognition on wearing one. They preferred longer length jacket to traditional Korean style, shorter length of skirt. They also preferred the traditional sleeve shape and knotted buttons. On the foundation of this fact, 2 styles consist of 5 Casual Hanbok design items made of functional material - Hanji yarn textiles that have antimicrobial, deodorant, quick drying, far infrared radiation which are not harmful to health - for New silver women were suggested. One style was 3 items - blouse, vest, skirt - which are the sense of Korean tradition with activity by patch. The other was 2 items - jacket and skirt - which are the sense of Korean tradition with modern way by quilting. Lastly, these garments were evaluated by 13 experts, they were satisfied with 2 styles and all items. As this study were based on the Elderly women living in Daejeon city, it had the limitation on applying of preference styles to all the New silver generation.

• Journal of Korean Tunnelling and Underground Space Association
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• v.2 no.2
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• pp.62-71
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• 2000

The abandoned mines causing settlement of the surface above and collapse of the cavities are the major influencing factor on the stability of the nearby underground structures. To prevent the harmful effect, the backfill methods are commonly applied to the cavities although the design criteria and the analysis method are not properly addressed in some cases. An approximate analytical method together with the numerical technique is considered in this study to simulate the gradual deterioration of the rock masses around the cavities and, therefore, the influential zone to the underground structures passing through the cavities. Also considered in this study is the backfill effect on the stability of the rock masses around the cavities. Specifically, the incomplete backfill effect is compared with that of the idealized backfill method by adopting elasto-plastic analysis involving a strain softening material law.

• Preventive Nutrition and Food Science
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• v.11 no.4
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• pp.348-357
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• 2006

Nano is a unit that designates a billionth; accordingly nanotechnology could be described as the study and applications of the unique characteristics and phenomena of nanometer size materials. Applications of nanotechnology fall into two categories (one is top-down and the other is bottom-up). Currently, most products are the results of the top-down approach. Nanofoods have distinct functional characteristics stemming from the size, mass, chemical combinations, electrolytic features, magnetic properties of food sources at the nano level and which can be applied for safe absorption and delivery into the body. The greatest advantage of nanofood is that it permits the efficient use of small quantities of nutritional elements by increasing digestive absorption ability and by delivering natural elements without any change in their original characteristics. On the other hand, there are still unsolved problems, such as questions about safety and introduction of harmful material. The demand for new commercial food products is increasing, and commercial food producers are gradually combining nanotechnology and traditional food preparation methods. Nanofoods will improve our eating habits remarkably in the future. Tomorrow we will design nanofoods by shaping molecules and atoms. It will have a big impact on the food and food-processing industries. The future belongs to new products and new processes with the goals of customizing and personalizing consumer products. Nanotechnology is expected to be applied to not only foods themselves, but also to food packaging, production, safety, processing and storage. Also, it is believed that nanotechnology will be applied tracking finished products back to production facilities and even to specific processing equipment in those facilities. The aim of this study is the introduction of technology, applications, products, markets, R&D, and perspectives of nanofoods in the food industry.

• Journal of Construction Engineering and Project Management
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• v.2 no.4
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• pp.20-24
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• 2012

Construction while being an economic activity that provides facilities and infrastructure, it is beneficial to man in some aspects and detrimental in others. There have been environmental concerns related to construction activities globally which mainly focus on atmospheric emissions, depletion of natural resources and energy issues. This study was carried out to assess the impacts of construction activities on the environment in Iganga Municipality and to propose measures for their mitigation. The methodology included: review of relevant literature, observations of the general environmental effects of construction activities, focus groups and a survey conducted among construction industry role players to determine their perceptions and opinions regarding environmental impact of construction activities. The collected data was presented in tabular form and analysed by description of responses to questions. The study revealed that forests were the most greatly degraded due to high demand of timber for construction followed by wetlands degradation. The findings of this study will be useful to architects, designers and builders in order to carefully design buildings and other infrastructure that are environmentally friendly and sustainable. Construction materials and their mode of acquisition are harmful threats to the environment. There is need to reduce the consumption of these materials through recycling and reusing wastes to reduce on waste generation, use of virgin materials and the subsequent waste of energy used in new material production.