• The Korean Journal of Pain
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• 제11권1호
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• pp.127-129
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• 1998

Intractable chest and abdominal wall pain responds well to root surgery. But it is better to perform this procedure less invasively with less complications. Cryoanalgesia has been developed to relieve several neurogenic pain without causing irrversible nerve damage. Well-selected percutaneous cryoablative procedure could be one of the technique of choice for some chronic pains because it has the advantage of easy application without any remarkable side effect. We did percutaneous cryoneurolysis of the spinal nerve root at the thoracic level to treat one patient with severe cancer pain on the chest wall(T4, 5, and 8 dermatomes) after successful percutaneous radiofrequency T6 and T7 posterior root rhizotomy. This procedure was performed under fluoroscopic guidance. We advanced 2 mm cryoprobe to the posterior, superior aspect of vertebral foramen on lateral view until the patient felt paresthesia. 3 times of 2 minutes freezing was applied to each spinal nerve root. The patient got immediate pain relief without any side effect.

• Computers and Concrete
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• 제5권6호
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• pp.573-597
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• 2008

Among artificial intelligence-based computational techniques, adaptive neuro-fuzzy inference systems (ANFIS) are particularly suitable for modelling complex systems with known input-output data sets. Such systems can be efficient in modelling non-linear, complex and ambiguous behaviour of cement-based materials undergoing single, dual or multiple damage factors of different forms (chemical, physical and structural). Due to the well-known complexity of sulfate attack on cement-based materials, the current work investigates the use of ANFIS to model the behaviour of a wide range of self-consolidating concrete (SCC) mixture designs under various high-concentration sodium sulfate exposure regimes including full immersion, wetting-drying, partial immersion, freezing-thawing, and cyclic cold-hot conditions with or without sustained flexural loading. Three ANFIS models have been developed to predict the expansion, reduction in elastic dynamic modulus, and starting time of failure of the tested SCC specimens under the various high-concentration sodium sulfate exposure regimes. A fuzzy inference system was also developed to predict the level of aggression of environmental conditions associated with very severe sodium sulfate attack based on temperature, relative humidity and degree of wetting-drying. The results show that predictions of the ANFIS and fuzzy inference systems were rational and accurate, with errors not exceeding 5%. Sensitivity analyses showed that the trends of results given by the models had good agreement with actual experimental results and with thermal, mineralogical and micro-analytical studies.

• Nuclear Engineering and Technology
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• 제41권8호
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• pp.1127-1134
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• 2009

Concrete has three major properties after a penetration-reinforcing agent is applied on its surface. First, the durability is improved by the sol-gel process of synthesized material from the polycondensation of TEOS (tetra-ethoxyorthosilicate) and acrylate monomer. Second, the capability to absorb impact energy is reinforced through the formation of a soft and flexible layer of organic monomers by Tea (Tetra Ethyl Amin). Third, the capability to prevent deterioration is enhanced by adding isobutyl-orthosilicate and alcohol. The performance and application of an agent developed through the synthesis of organic and inorganic material in an effort to prevent concrete from deterioration and improve the durability of concrete structures were verified in diverse experiments. The results of these experiments showed that the application of the proposed penetration-reinforcing agent has the effect of increasing the compressive strength by filling up the internal pores of concrete with physically and chemically stable compounds after penetrating the concrete. It also improves the durability against the deterioration factors such as salt water damage, carbonation, freezing and thawing, and compound deterioration. Therefore, it is confirmed that the penetration-reinforcing agent is a useful substance for the management and repair of concrete structures.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.351-354
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• 2005

Quality of concrete required to achieve the desired levels of strength and durability depend on the effectiveness of the curing method. During cold weather, the concrete at the time of placement should be taken to prevent damage to concrete due to freezing. Since the cement-water reaction is exothermic by nature, the temperature within mass concrete can be quite high. The temperature control for massive sections should be taken more careful than for shallow sections. However, in the constructing hydraulic structures, the curing temperature control for concrete had been very difficult to be taken in a proper way because the conditions constructing them are poor and contractors are small enterprises. For several. reasons including above, Rural Research Institute has developed a device and program for recording curing temperature history in cold weather concrete and mass. As there are two major advantages of the device, namely cheapness and availability, this program and device has been recommended to the use of curing temperature control in cold weather concrete and mass.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.21-22
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• 2009

본 논문에서는 SHCC로 단면 복구된 콘크리트 보가 동결융해 환경에 노출되는 경우 그 휨 보강 및 균열제어 특성에 대한 실험결과를 제시한다. 본 연구에서 사용된 SHCC는 PVA 및 PE 섬유를 각각 0.75% 보강한 것이며 물결합재 비를 주요변수로 한다. 실험결과 SHCC로 휨 인장측이 단면 복구된 콘크리트의 휨내력은 동결융해의 노출 유무에 따라 각각 2.42 및 3.31배 증가되었다. 또한 휨 인장측의 균열제어 성능도 우수하게 나타났으나 이러한 성능은 동결융해에 노출됨에 따라 저하되는 특성을 보였다. 이는 시멘트 복합체와 섬유계면이 반복 동결융해에 의해 손상되었기 때문인 것으로 판단된다.

• 한국식품영양과학회지
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• 제28권6호
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• pp.1283-1287
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• 1999

This study was carried out to develop new processed food from cherry tomatoes. The dried cherry tomatoes were prepared by using a sequence of osmotic dehydration, air drying, vacuum drying and freeze drying. The moisture contents of dried cherry tomato products by nontreatment and osmosis treatment were about 11~13% and 7.5~ 10%, respectively. The vitamin C contents of the dried product after osmotic dehydration were higher than those of the dried products by nontreatment. The vitamin C content of the freezing dried product was the highest of the others. The vacuum dried product by nontreatment was retained color of fresh fruit in the change of color. The ΔE value of the air dried product was lower than those of the others. As a result to microscopic analysis, fresh cherry tomato was observed regular tissue, while cherry tomato treated by osmosis was observed a cell collapse following the loss of water. The dried product had cell shrinkage and dense tissue. And the cell wall of dried products after osmotic dehydration were much more damage than those of nontreatment dried product. The palatability of the air dried product was the best of three drying methods. The dried cherry tomatoes treated by osmosis were superior to the dried cherry tomatoes by nontreatment.

• 보존과학연구
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• 통권30호
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• pp.125-136
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• 2009

Stone cultural heritages in Korea have a severe damages from chemical and biological weathering because most of them have been situated in outdoors without any suitable protection systems, and this in turn causes deformation and structural damage. To counteract these problems and increase durability, various kinds of conservation materials are used in the conservation and restoration treatments. However until now there are not many practical and technological experiments on this subject. This paper attempts quantitative evaluation of effectiveness about chemical of ethylsilicate based resin for sandstone in Yeongyang-gun. It takes a long time to evaluate durability and side effect after conservation materials treatment. So we use artificial weathering through freezing§ thawing experimental method. As a result of this experiment, porosity and absorptance increased, and elastic wave speed, elastic modules, unconfined compression strength and tensile strength decreased more than before. This study plans to make a scientific method study about weathering factor and mechanism, and to deduce correlation between artificial weathering and natural weathering.

• 한국조리학회지
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• 제5권2호
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• pp.165-190
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• 1999

There are no reliable data about the effect on the baking industry in Korea yet. The damage caused by the product's aging is so much in the confectionary and baking industries. Therefore, the aging of bread is an economical problem which determines its commercial lifespan. In order to solve out this aging problem, this article dealt with the factors which give rise to the effect of starch on the aging and its inhibitory methods. 1. Control of the moisture content : Because the aging of starch occurs at 30~60% of moisture most frequently, controlling the moisture content above or below the above percentage can help restrain the aging to a certain degree. 2. Addition of sugars : The sugars become hydrated through hydrogenation with the moisture in the food. Thus, the sugars suppress the phenomenon of crumbling inside the food acting as a kind of dehydrator. 3. Use of an emulsifying agent : The emulsifying agent increases the stability of starch colloid liquid and suppresses the precipitation of starch molecules and the formation of crystallized range to prevent aging. 4. Method by freezing : The aging of starch does hardly occur reaching -2$0^{\circ}C$~-3$0^{\circ}C$ below zero. 5. Maintenance of warm condition : The freshness of bread is maintained at the 80% of humidity at 5$0^{\circ}C$.

• Journal of Oral Medicine and Pain
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• 제23권3호
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• pp.249-255
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• 1998

Mucoceles of the minor salivary glands are the most common cystic lesions affected the oral mucosa. They are believed to be the result of trauma to the salivary duct caused, for example, by biting the lip, cheek, or tongue. Surgical excision has been the most common treatment for these lesions, but occasional recurrences develop after excision because surgical trauma may damage the surrounding minor salivary glands Although various alternative nonsurgical approaches, such as steroid infection, application of gamma-linolenic acid, have also been reported, they are not used routinely, Lasers, particularly the carbon dioxide laser, have been used in the management of mucoceles. Although this treatment requires specialized equipment. Cryotherapy is another effective nonsurgical method for treating mucoceles. Clinically, cryotherapy has primarily been applied to the treatment of leukoplakia and hyperplastic, granulomatous, vascular, and pigmented lesions. Limited information, however, is available on the application of cryotherapy in salivary gland lesions, including mucoceles. A simple and easy cryotherapy to treat a mucocele on the lower lip is described. A 25 years old female patient with a mucocele on the lower lip was treated by direct application of liquid nitrogen with a cotton swab. The lesion was exposed to 4 or 5 cycles composed of freezings of 10-30 s and thawings of double the freezing times. No anesthesia was required. The lesion nearly disappeared without scar 10 days after the cryotherapy. Cryotherapy has become an established nonsurgical method, characterized by its simple application, therapeutic effectiveness, painless during the procedure and low incidence of secondary infection and hemorrhage.

• 설비공학논문집
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• 제24권4호
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• pp.336-342
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• 2012

Large-scale active solar heat systems are generally using heat exchanger between collector and storage tank loops to prevent damage by freezing. It is difficult to maintain stratification in a storage tank in the system owing to greater flow rate enhancing heat transfer. In the previous study, we introduced a spiral-jacketed storage tank and obtained good results to keep system performance of general level without better stratification. We added a scroll-shaped heat exchanger coil on the upper part in the spiral-jacketed storage tank. As a result of the experiment, it was verified that degree of stratification of the new type storage tank is higher than that of the previous one with a possibility of better collector efficiency and solar fraction.