• Journal of the Korean Wood Science and Technology
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• v.35 no.2
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• pp.61-68
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• 2007

The applicable scope of adhesives in the current society is broad and currently, several types of PVAc resin are sold in the market for adhesives. PVAc resin is primarily used for wood works and paper adhesion. However, the PVAc resin itself has the disadvantages that its viscosity is highly temperature- dependent and the work condition and viscosity get worse at the low temperature in the winter seasons. Although phthalate-based plasticizer is used to complement these disadvantages, adhesion strength and heat-resistance are weakened by adding the phthalate-based plasticizer and in the winter period, the amount of quantity should be increased. Also in a high-density product, it worsens the work condition by causing a rise of viscosity and delays curing and in a low-density product, it worsens the storage stability by causing separate precipitation. In addition to these, the phthalate-based plasticizer as a material of causing environmental hormones is currently restricted in the advanced countries for its amount of use and also in the domestic market, it is necessary to prepare for the situation. This study has not only eliminated the disadvantages of PVAc resin emulsion without adding a phthalate-based plasticizer of causing these problems, but also synthesized the PVAc resin for timber adhesion that is excellent in woodwork, thermal-resistance, water-resistance, storage stability, and adhesion performance. As the result, it has proven an excellent performance in thermal resistance, water resistance, storage stability, and minimum film forming temperature.

• Polymer(Korea)
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• v.24 no.4
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• pp.520-528
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• 2000

New high solid acrylic resins (BMHA) containing 70% of solids content have been synthesized. The environmental friendly high solid coatings (BNHS) were prepared by using these acrylic resins and polyisocyanates. The BMHA was obtained by introducing a new functional group, acetoacetoxyethyl methacrylate (AAEM), in the copolymerization of n-butyl acrylate, methyl methacrylate, and 2-hydroxyethyl acrylate. Lowering T$_{g}$ and increasing the AAEM amount in the BMHA resulted in a high value of conversion. There was no difference in conversion with the variations of OH values. In the next step, high solid BNHS coatings were prepared by the curing reaction between BMHA and polyisocyanate at room temperature. The properties of these coatings were evaluated especially for the application of automotive top-coating materials. The introduction of AAEM in the BNHS enhanced the abrasion resistance and solvent resistance of the coatings, which indicated the possible use of BNHS coatings for top-coating materials of automobile..

• Journal of Korean Medical classics
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• v.30 no.2
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• pp.45-57
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• 2017

Objectives : There exists a number of books that deal with curing diseases with foods. This includes Shennongbencaojing from Han Dynasty era, Zanyin's Shiloaoxingan and Mengxi's Shilaobencao from Tang Dynasty era, Husihui's Yinshanzhengyao from Won Dynasty era, and Feiboxiong's Sikgamboncho from Qing Dynasty era. This paper aims to delve into the food treatment revealed in Sikgamboncho, which is the latest book in the preceeding list, and studied its differences when compared to other medical books that deal with food treatment methods. Methods : The format and contents of Feiboxiong's Sikgamboncho were studied. For its format, Shilaoaoxingan, Yinshanzhengyao, Shikryochanyo, and Donguibogam were used to compare their formats with that of Sikgamboncho in order to discern the unique characteristics found in the book. For its contents, the paper studied food ingredients and food treatment separately, and then studied the historical significance of Feiboxiong's Sikgamboncho. Results : Sikgamboncho categorizes 12 types of grain, 22 types of vegetables, 7 types of cucumis calyx, 27 types of fruit, 9 types of flavor, 4 types of bird, 4 types of animal, 10 types of fish with scales, 4 types of carapace, and 2 types of worm. The book explains each ingredient's harvest period, its nature, potency, and taboos. The food treatment section explains 74 types of treatments that are divided between the wind, cold, summer heat, dampness, dryness category and the qi, blood phlegm, deficiency, and excess category. Each treatment contains its potency and recipe. Conclusions : Feiboxiong underlined the importance of ingredient through placing significance even to the order of ingredients. Out of the total 74 food treatments, 25 treatments were dedicated to deal with weakness. Feiboxiong attempted to prevent human body from becoming weak, which reflects his emphasis on the importance of food and wellness.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.2
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• pp.257-262
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• 2016

This study was conducted to compare the physicochemical traits of dry-cured hams made from two different three-way crossbred pigs: Yorkshire${\times}$Landrace${\times}$Duroc (YLD) and Yorkshire${\times}$Berkshire${\times}$Duroc (YBD). Animals were slaughtered at a live weight of 110 to 120 kg and cooled at $0^{\circ}C$ for 24 h in a chilling room, the ham portion of the carcasses were cut and processed by dry-curing for physico-chemical analyses. While the moisture and crude protein contents of dry-cured ham were higher in YLD than in YBD, crude fat and ash content were higher in YBD (p<0.05). The salt contents of ham from YBD were higher than those from YLD (p<0.05). YBD ham samples showed a higher $L^*$ and $b^*$ values than those from YLD, while YBD ham showed lower $a^*$ value (p<0.05). Thiobarbituric acid reactive substances (TBARS) and volatile basic nitrogen (VBN) values of YLD hams were lower than those of YBD samples (p<0.05). Hardness, gumminess, chewiness, and shear force values of YBD ham were higher than those of YLD sample (p<0.05). Saltiness was significantly higher in YBD ham than in YLD samples (p<0.05). YLD ham displayed a superior quality than YBD. Considering the meat quality parameters of two-way crossbred ham, YLD hams could be more suitable for the production of dry-cured products.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.441-444
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• 2011

Type A and Type B and are commercial HTPB models, which are very popular prepolymer for polyurethane binder family. So the study has been performed on the physical, chemical characteristic of HTPB and viscosity, mechanical property of PBX-A applying to HTPB. But We excluded the Type A from Appication test, because of law Hydroxyl value. And in the case of Type B, Type B-1, 2 has mechanical disadvatage to apply to HTPB in the process comparing with B-3. It seems to make no problem if we change equivalence ratio or curing condition within standards. But if we are to apply process condition like R-45HT(US-sample), it would be essential to apply HTPB with higher Hydroxyl Value and hydroxyl Functionality.

• Journal of the Korean Society of Propulsion Engineers
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• v.13 no.5
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• pp.1-6
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• 2009

A development of a composite solid propellant is carried out for an application to gas generators as an energy source of rocket system. With HTPB as a propellant binder which has 80% of particle loading ratio, a favorable rheology, and moderate curing properties at the range of $-50^{\circ}{\sim}70^{\circ}C$, AN is selected as the first kind of oxidizer having the characteristics of a low flame temperature, minimal particle residual as well as nontoxic products. AP is the second oxidant for ballistic property control. A series of experiments for the improvement of physical properties were conducted and resulted in the propellant formulation having 30% of strain rate at 8 bar of max. stress.

• Journal of the Korean GEO-environmental Society
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• v.15 no.10
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• pp.29-34
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• 2014

In order to examine strength properties depended on climate changes of solidified soil amended by porosity silica which enhance harms of cement, this study conducts a wetting and drying repetition test and then, attempts to verify strength properties before and after solidified soil gets environmental influence. Test pieces for the unconfined compression test changed the mixing ratio of solidified soil compared to mixed soil weigh to 5 %, 10 % and 15 %. For each step, it was created by mixing 0.5 %, 1.0 % and 1.5 % of wood chips, and curing period for 7, 14, and 28 days. Then, the wetting and drying repetition process was repeated 0, 3, 6, and 12 cycles to analyze mechanical properties. To also evaluate changes of relative dynamic elastic modulus before and after the wetting and drying, dynamic elastic modulus tests were conducted when each cycle was completed.

• Korean Chemical Engineering Research
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• v.50 no.6
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• pp.1076-1081
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• 2012

For the purpose of development of the latex suitable for latex modified concrete, experimental researches on the preparation of carboxylated styrene butadiene latex by the method of the two-step emulsion polymerization and application to concrete were performed. Sodium dodecylbenzene sulfonate and sodium salt of lauryl sulfonate were selected as anionic emulsifiers, and nonylphenoxy poly(ethyleneoxy) ethanols (n=10, 20, 40) as latex stabilizer. Potassium persulfate and sodium bisulfite were used as redox initiator, besides $Na_2HPO_4$ and $K_2CO_3$ as electrolytes. Polymerization recipe of latex suitable for latex modified concrete were suggested from the experimental researches on the effects of anionic emulsifiers and their concentration on the polymerization stability, and the effect of electrolytes concentration on the particle size of latex. Physical properties, such as slump, air contents, compressive and flexural strength, of latex prepared by suggested polymerization recipe were examined. The experimental results showed that latex modified concrete satisfied the quality standards in slump and air contents. Furthermore, it was turned out that the compressive and the flexural strength of latex modified concrete with 28 days curing time showed appreciably improvements.

• Journal of Korean Academy of Nursing
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• v.24 no.3
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• pp.327-344
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• 1994

It is needed that nursing scholars in Korea should understand the philosophy and perspectives of oriental medicine, and then explore the possiblities of theory building which can be a Korean’s unique nursing theory. With the assumption of this kind of work can be achieved by cooperation of oriental medicine and nursing areas, this study measures the subjectivity -opinions, attitudes, and values-of professional from these two areas. Identifing the schemata(structure of subjectivity) would be a basic step for the strategies and construction of oriental nursing theory. The Q-sorts of 57 professionals were combined into five distinctive factors, namely, Q-types. The five factors were named as follows : Type I, Fundamentalist, consistently insists that the understanding of oriental medicine should be a basic step for the development of oriental nursing model, because ororiental medicine's theories and practices in curing are very unique and different from the western. Type Ⅱ, Pessimist, denies the uniqueness of oriental nursing field and its independency, because of lack of scientific evidences and professionalism. Type Ⅲ, Harmonist, believes the basic concepts in two different medic관 spheres are identical, but, at the same time, accept the uniqueness of the two. They try to propose Korean Nursing Model which accomodates local culture and conventions, and the way of Nurturing Life(Yang-sang), based on the traditional western nursing. Type W. Needy Follower, merely expects the Korean Nursing Model which considers the characteristics of Koreas culture and physical constitution and, thus, is more suitable to them. Some-times, they experience the discontent and conflict when they need more qualitative and culture-oriented nursing interventions. Type V, Alternative Giver, actully clarifies the concept of Oriental Nursing, and provides specific program as a alternative of universal western nursing. Various ways of Nurturing Life (mental, life, and diet Yang-sang) were introduced as a guideline for the specification of the nursing area and its con-tent. Throughout the study, the five different Q-factors were identified, and the concept of Oriental Nursing and aspects of its theory construetion were discussed.

• Korean Journal of Soil Science and Fertilizer
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• v.12 no.1
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• pp.43-46
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• 1979

Curing the studies on the mechanism of the nodule formation and the infection of rhizobia using the continously cultured plant cell tissues, it was found that some calluses possess high nitrogen fixation activity. This experiment was conducted to know the differences among the calluses and the Rhizobia. The results obtained were as follows; 1) In a single inoculation the nitrogenase activity of soybean cell cultures-rhizobium was moderately higher than non-leguminous cell cultures, however, in the mixing inoculation that was reversely found. 2) Host factor, which was characteristics for the nodule formation and the nitrogenase activity, was not appeared generally in the plant cell cultures except for Kuamusume and Toyozuzu in soybean, and Datura in non-leguminous cell cultures. 3) In the 012 rhizoblium cultured on soybean cell cultures and in the 010, 023 and 024 rhizobia cultured on non-leguminous cell cultures the nitrogenase activity higher than the others.