• Geomechanics and Engineering
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• 제16권4호
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• pp.375-384
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• 2018

Unconfined compressive strength (UCS) of high plasticity clayey soil mixed with 5 and 10 % of Portland cement and four chemical agents such as sodium hexametaphosphate, aluminum sulfate, sodium carbonate, and sodium silicate with 0, 5, 10, and 20% concentrations was comparatively evaluated. The individual and combined effects of the cement and chemical agents on the UCS of the soil mixture were investigated. The strength of the soil-cement mixture generally increases with increasing the cement content. However, if the chemical agent is added to the mixture, the strength of the cement-chemical agent-soil mixture tends to vary depending on the type and the amount of the chemical agent. At low concentrations of 5% of aluminum sulfate and 5% and 10% of sodium carbonate, the average UCS of the cement-chemical agent-soil mixture slightly increased compared to pure clay due to increasing the flocculation of the clay in the mixture. However, at high concentrations (20%) of all chemical agents, the UCS significantly decreased compared to the pure clay and clay-cement mixtures. In the case of high cement content, the rate of UCS reduction is the highest among all cement-chemical agent-soil mixtures, which is more than three times higher in comparison to the soil-chemical agent mixtures without cement. Therefore, in the mixture with high cement (> 10%), the reduction of the USC is very sensitive when the chemical agent is added.

• 조명전기설비학회논문지
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• 제18권6호
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• pp.1-7
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• 2004

고압방전등을 점등하기 위해서는 고전압의 시동전압이 필요하게 되는데, 이러한 시동전압은 고압력의 나트륨램프에서도 필요하게 된다. 자기장은 전기 방전튜브에서 만들어지게 되며 증기 원자에 대한 전자충돌이 가속화되면서 2차 전자가 발생하고 전기 방전튜브에 전류가 급속도로 흐르게 되며, 나트륨램프의 제작회사마다. 서로 다른 램프의 수명 및 교환시점도 서로 다르다는 것을 본 논문의 연구과정에서 발견하게 되었다. 본 논문에서는 LabVIEW소프트웨어패키지를 사용 중인 나트륨램프의 교환시점의 알고리듬을 제안한다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 지반공학 공동 학술발표회
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• pp.453-460
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• 2005

Sodium silicate - the usual portland cement which accomplishes a cement pouring reconsideration main stream and sodium silicate(No.3) after reacting sodium silicate(No.3) with the reaction sodium silicate where oxidation natrium which is included does not react with the cement receiving stiffening water it will burn together on underwater and to become the durability lacks pouring it is recognized. From the hazard which improves an advantage it used the additive which relates in congealing and stiffening of the portland cement and sodium tripolyphosphate(STPP) addition hour initial material age(72 hours at once) which does to be revealed the at high-in-tensity is discovered while accomplishing. The effect of additives on the reactions of sodium silicate solution and cement suspesion was investigated by various physical and chemical tests, such as Si-NMR, XRD, SEM uniaxial compression test. The additives were STPP(sodium tripolyphosphate), EDTA, SUGAR. The compressive strength of sodium silicate(No.3) - cement grout with additives was about $1.5{\sim}10$ times higher than that without additive in early age(72 hours).

• 식품과학과 산업
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• 제49권2호
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• pp.34-44
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• 2016

Given that fermented foods, such as kimchi and doenjang, are main food sources for high sodium intake in Korea, there have been needs to develop sodium-reduced kimchi and doenjang with the proper quality. However, small and medium sized business could not actively develop the sodium-reduced products due to lack of techniques and information as well as economical reasons. The most important aspects is to address food safety issues including microbial contaminations in sodium-reduced foods. Hurdle Technology, physical, biological, chemical control technique, would have to be preferentially considered to increase the hygiene safety standards in entire processing steps including raw materials, process water, manufacturing environments, and so on. Once the food hygiene level is stable, the next challenges are to improve the taste of the sodium reduced-products as well as to packaging and storage technologies. The development of a variety of sodium-reduced fermented foods would result in significant mitigation of sodium intake by Korean. This report provides the directions to develop sodium-reduced kimchi, doenjang or pickled food products for small and medium sized business, based on the technical consulting results of sodium reduction project supported by Ministry of Food and Drug Safety in 2015.

• International Journal of Oral Biology
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• 제47권4호
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• pp.49-54
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• 2022

Taste is a basic sensation to get attracted toward nutritious foods or avoid possible harmful substances. The basic taste qualities in humans consist of sweet, bitter, umami, salty, and sour. Basically, sweet and umami tastes make food attractive, whereas bitter and sour tastes make it avoidable. Salty taste comprises basic salty and high salt taste. The basic salty taste is known as amiloride-sensitive salty taste, which is inhibited by amiloride, but the high salt taste is not sensitive to amiloride. Moreover, high salt taste can also cause avoidance behavior in human beings. Sodium, one of the most important cations in the body fluids of vertebrates, controls the volume of total body fluids and is a risk factor for cardiovascular diseases, such as hypertension. The concentration of sodium in body fluids must be under delicate control. A distinction between the salty taste and high salt taste would be a contributing mechanism to control the volume and/or osmolarity of body fluids.

• Journal of Community Nutrition
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• 제8권4호
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• pp.193-199
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• 2006

There have been many studies indicating increased salt intake is related to elevated blood pressure (BP). Hypertension and pre-hypertension are prevalent in Korea. A national survey showed that the Korean average daily salt consumption was 12.5g, which is more than twice the current recommendation in the UK or USA. This study was performed to understand which aspects of the Korean diet contributed to high salt intake and elevated BP in Korea. The subjects consisted of 1,110 Korean adult men aged 30 to 49 years who were selected from the data of 2001 Korean National Health and Nutrition Survey, a nationwide cross sectional survey. The relationship of BP with sodium and high sodium food intakes were analyzed. After categorizing subjects according to their BP, the socio-demographic information and food and nutrients intakes were analyzed. BP increased with a larger amounts of sodium intake and the trend was significant with diastolic BP. However, the trends of BP for sodium densities of the diet were not. People with hypertension significantly tended to be older, larger, and less educated than people with normal BP. And they consumed more foods from the fats, oils & sweets group and larger amounts of discretionary sodium than normal people. The current report advocates that public health intervention, which improves the awareness of the role of salt on elevated blood pressure for the public, should be implemented in Korea.

• Nuclear Engineering and Technology
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• 제41권10호
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• pp.1323-1332
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• 2009

The IHX (Intermediate Heat eXchanger) for a pool-type SFR (Sodium-cooled Fast Reactor) system transfers heat from the primary high temperature sodium to the intermediate cold temperature sodium. The upper structure of the IHX is a coaxial structure designed to form a flow path for both the secondary high temperature and low temperature sodium. The coaxial structure of the IHX consists of a central downcomer and riser for the incoming and outgoing intermediate sodium, respectively. The IHX of a pool-type SFR is supported at the upper surface of the reactor head with an IHX support structure that connects the IHX riser cylinder to the reactor head. The reactor head is generally maintained at the low temperature regime, but the riser cylinder is exposed in the elevated temperature region. The resultant complicated temperature distribution of the co-axial structure including the IHX support structure may induce a severe thermal stress distribution. In this study, the structural feasibility of the current upper support structure concept is investigated through a preliminary stress analysis and an alternative design concept to accommodate the IHTS (Intermediate Heat Transport System) piping expansion loads and severe thermal stress is proposed. Through the structural analysis it is found that the alternative design concept is effective in reducing the thermal stress and acquiring structural integrity.

• 대한지역사회영양학회지
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• 제20권5호
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• pp.327-337
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• 2015

Objectives: Dietary life is closely associated with dietary attitude and diet-related knowledge. Particularly, dietary habit such as sodium intake can be affected by various dietary behaviors such as food choices, dietary attitude toward salty food and a preference for salty taste. The purpose of this study was to assess sodium-related nutrition knowledge and to identify sodium-related attitude and behaviors according to the level of sodium-related knowledge of university students. Methods: Anthropometric measurements were provided by 408 students who participated in this study. The study participants answered questionnaires to provide information on general dietary behaviors, sodium-related dietary attitude and other behavioral factors. A total score of nutrition knowledge was used to categorize study participants in to two groups, namely, low level in sodium-related knowledge (LNaK) or high level in sodium-related knowledge (HNaK) and the attitude and the behaviors of students toward sodium intake were compared between these two groups. Results: The ratio of female students in HNaK group was higher than that in the LNaK group. HNaK group had a higher score in checking nutrition label of processed food than the LNaK group. Total score of sodium-related attitude and behaviors of HNaK group were 34.81 and 32.75, respectively and these scores were significantly higher than that of the LNaK group whose scores were 32.57 and 30.57, respectively. Total energy intake was not different between two groups but the intakes of calcium, vitamin B2 and folate were higher in HNaK group than in the LNaK group. Correlation analysis adjusted for age and gender revealed that total score of sodium-related nutrition knowledge was positively correlated with total score of sodium-related attitude and behaviors. Conclusions: In conclusion, students who had high level of sodium-related nutrition knowledge had desirable attitude and behaviors toward sodium intake and these results can be considered in nutrition education for university students.

• 약학회지
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• 제42권3호
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• pp.284-289
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• 1998

The effect of reaction condition, solvent addition and thermal treatment on the bulk density, crystallinity and chemical properties of the freeze-dried cefazohn sodium was inves tigated to prepare the cefazolin sodium powder for injection with good flowability. Crystalline cefazolin sodium powder with high untapped-bulk density (about 45%) and low compressibility (about 40%) was obtained by solvent addition to the very highly concentrated cefazohn sodium solution followed by subsequent thermal treatment before freeze-drying. The desirable solvent was low substituted alcohol such as isopropyl alcohol and anhydrous ethanol with the final concentration of about 9%. The pH adjustment and nitrogen gas purging during the reaction did not give significant effect on the chemical properties such as content, color, transmittance and pH of the reconstituted cefazolin sodium aqueous solution.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제3권3호
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• pp.169-175
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• 1999

2,4-Dinitrophenol(DNP) is a metabolic uncoupler that prevents cells from creating energy for growth and it has been suggested that the availability of sodium ions may be important in mitigating the effects of uncouplers. Accordingly, the degradation of DNP was investigated using activated sludge which had been adapted to mineralize DNP. After the acclimation of the activated sludge, the effect of sodium ions on the toxicity of high concentrations(80 to 100mg/L) of DNP was investigated over a sodium ion concentration range of 9.3$\times$10-5 to 94mM. The concentration of sodium ions in the activated sludge mixed liquor seemed to have little effect on the DNP toxicity. However, a lack of sodium in the grwoth media resulted in a reduction of the DNP degradation rate by a bacterial isolate from the activated sludge culture identified as Nocardia asteroides.