• 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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.10
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• pp.23-29
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• 2020

The soil structures settle down continuously under cyclic dynamic loading after opening railway lines. This study examined the characteristics of the settlement and stiffness of cement-treated soils with the change in the content of fines under cyclic dynamic loading. Eighteen cases of the test were carried out with the changes in the fines content of soils, cement content, and curing days. Based on the test results, cement-treated soils containing more than 3% of cement could decrease settlement sufficiently even with a high portion of fines under cyclic dynamic loading. In addition, the elastic and plastic settlements could be reduced using 3 to 4% cement to the level of 1/4 and 1/6, respectively. In the viewpoint of stiffness, the resilient modulus of cement-treated soils increases with increasing cement content. Using more than 3% of cement, the 80MPa compaction stiffness standard for the upper subgrade of railways was satisfied, even with 40% of fines content of soils.

• The Korean Nurse
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• v.34 no.1
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• pp.74-87
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• 1995

This study was to investigate the current prevention Mechanism of tuberculosis infection and to find out how nursing teachers handle against tuberculosis infection. The objectives of this study was to aid in better treatment and maintenance of those infected-students and help students to prevent the disease by themselves. The subjects of this research were 78 students who were proved to be infected at tuberculosis by the test result of each high school and 35 nursing teachers who retain those 78 infected students. The results of this study were as follows: 1. The infection rete of tuberculosis and the general characteristics of the infected students at Girls' High School: There are approximately 33 and 50 tuberculosis-infected cases in 1992 and 1993. The tuberculosisinfection rate were 0.12% in 1992, while the infection rate were 0.17% in 1993. The infection rate for academic Girls' High School stucents were 51.3%, while that of vocational Girls' High school students were 48.7%, About 30.8% of respondents have a family history of tuberculosis infection. 2. The current management system of tuberculosis treatment: It was reported that 59.0% of respondents out of total cases were in the process of treatment, and 41% of them were recovered (from tuberculosis). 55.1% of respondents use health center as their most frequent treatment location. 57.5% of academic Girls' High School and 47.4% of vocational Girls' high shool reported inconsistent meals while curing tuberculosis. In terms of taking medicine, 55.1% reported inconsistently. 3. The current management system of nursing teachers; Approximately 57.1% of nursing teachers were at academic Girls' High School. while 42.9% were at vocational Girls' High School. While treating tuberculosis, 85.7% of nursing teachers checked the consistent medicine-taking, 54. 3% of them checked the side effects of medicine, 80% of them consulted with students, while only 25. 7% of them check the school attendance. This study also finds out that we have underestimated the importance of tuberculosis treatment and health education at the shool level, it has not been effective enough for students to recognize the importance of tuberculosis. It is our assertion that nursing teachers should have paid much more attention to tuberculosis itself and infected-cases.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.4
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• pp.662-669
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• 2020

Objective: This study was conducted to evaluate the effect of red glasswort (RG) (Salicornia herbacea L.) curing on the physicochemical, textural and sensory properties of cooked pork loin ham (M. longissimus thoracis et lumborum). Methods: All treatments were cured with different salt and RG powder levels. RG0 treatment was prepared with only 4% NaCl (w/w) as a control, and RG25, 3% NaCl:1% RG (w/w); RG50, 2% NaCl:2% RG (w/w); RG75, 1% NaCl:3% RG (w/w); RG100, 0% NaCl:4% RG (w/w) treatments were prepared sequentially. All samples were individually vacuum packaged in polyethylene bags and stored for 7 d at 3℃±1℃. Results: The results showed that as the rate of RG substitution increased, pH value, redness, myofibrillar protein solubility, and myofibrillar fragmentation index increased (p<0.05), but salt concentration and shear force decreased (p<0.05). However, there were no significant differences in cooking loss and moisture content. In terms of sensory evaluation, RG100 exhibited higher scores in tenderness and juiciness than RG0 (p<0.05). Conclusion: The partial substitution of NaCl by RG could improve the physicochemical properties, textural and sensory characteristics of cooked pork loin. Therefore, it is suggested that RG as a natural salt replacer could be an effective ingredient for developing low-sodium cured hams.

• Polymer(Korea)
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• v.38 no.2
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• pp.171-179
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• 2014

Low temperature cure prepregs are being developed for use in the preparation of large-structured fiber-reinforced polymer (FRP) composites with good performance. Cure behavior and chemorheology of low temperature cure epoxy resin system, based on epoxy resin, curing agent, and accelerators, were investigated to provide a matrix resin suitable for the prepreg preparation. Characteristics of cure reaction were studied in both dynamic and isothermal conditions by means of differential scanning calorimetry and rheometry. The low temperature cure epoxy resin system suggested in this study as a matrix resin was curable at $80^{\circ}C$ for 3 h, and showed the gel times of 120 and 20 min at 80 and $90^{\circ}C$, respectively. Thermal and mechanical properties of the cured sample were almost the same as high temperature cure counterparts.

• Journal of the Korea institute for structural maintenance and inspection
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• v.8 no.4
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• pp.87-96
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• 2004

As a special concrete, which is a mixture of soil, cement and water, has strength like regular concrete for pavement, soil cement has been used in various field such as pavement and soft soil improvement. The objective of this study was to investigate the characteristic of unconfined compressive strength and time dependent behavior of soil cement that is made from decomposed granite soil or coluvial and inorganic solidification liquid. The results showed that the unconfined compressive strength appears to increase as the amount of cement and curing time increase In addition, the strength seems to decrease with increase of the potion of fine particles(No 200 sieve). The result of XRD indicated that there is Vermiculite, the product of reaction, in the soil cement. The dynamic properties of material, such as shear complex compliance, shear complex modulus, and phase angle could be calculated from the hysteresis loop obtained from the Haversine Creep Tests. Finally, creep behavior was able to be predicted from these dynamic properties.

• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.1
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• pp.26-34
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• 2013

Durability performance in RC structures varies significantly with changes in cover depth and mix proportions. GGBFS (Ground Granulated Blast Furnace Slag) is very effective mineral admixture and widely used for an improved resistance to chloride attack. In this paper, characteristics such as porosity, compressive strength, and diffusion coefficient are evaluated in GGBFS concrete with 30~70% of replacement ratio and $4,000{\sim}8,000cm^2/g$ of fineness. Through the tests, more dense pore structure, higher compressive strength, and lower diffusion coefficient are obtained in GGBFS concrete, which are evaluated to be more dependent on replacement ratio than fineness. With increasing curing period from 3 to 91 days, porosity decreases to 77.47% and strength increases to 373% in GGBFS concrete. Chloride diffusion coefficient in GGBFS concrete decreases to 64.4% compared with that in OPC concrete, which shows significant improvement of durability performance.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.2 s.25
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• pp.35-44
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• 2007

Plowable fill is generally a mixture of sand, fly ash, a small amount of cement and water. Sand is the major component of most flowable fill mixes. Marine dredged soil was adopted for flowable fill instead of fly ash. Natural sea sand and in-situ soil were used for comparison. The flow behavior, hardening characteristics, and ultimate strength behavior of flowable fill were investigated. The unconfined compression test necessary to sustain walkability as the fresh flowble fill hardens was determined and the strength at 3-days appeared to correlate well with the water-to-cement ratio. The strength parameters, like cohesion and internal friction angle, was determined along the curing time. The creep test for settlement potential was conducted. Also, potable falling weight deflectometer(PFWD) test has been carried out for elastic modulus of each controlled low strength materials(CLSM). The data presented show that marine dredged soil and in-situ soil can be successfully used in CLSM.