• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2000년도 추계학술발표논문집
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• pp.83-83
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• 2000

Alkylketene dimer was known as a cellulose reactive or alkaline size because it does not require to fix to the fiber as do the traditional rosin sizes. A proposed sizing mechanism of AKD was the formation of P -ketoester bond between AKD and cellulose which provides the permanent attachment and the orientation of the hydrophobic alkylchains outward. However, some questions about the reaction had arisen and thus, the sizing mechanism of AKD has been a subject of controversy for several decades. The major concern of the controversy is that AKD is really reactive with cellulose or not in the papermaking conditions. In this study, reaction between AKD and pulp fiber was investigated, in order to find out whether AKD forms P-ketoester with pulp fiber during aging under no catalyzed neutral condition with obvious spectroscopic evidence. In addition, effect of aging treatment on the sizing development was studied. It has been disclosed that, in absence of water, AKD reacted with cellulose to form P -ketoester linkage under no catalyzed neutral condition, while, in presence of water, most of AKD was hydrolyzed to a dialkyl ketone or P -ketoacid. In addition, during the aging treatment of AKD-sized paper, its typical IR spectra bands gradually were reduced, completely disappeared after 6hr aging, and formed new absorption bands at 1707cm-' and shoulder peak at 1700cm-' which refer to the typical dialkylketone absorption bands. Therefore, the formation of P -ketoester between AKD and pulp fiber is impossible in the practical papermaking process. It could be suggested that the sizing development of AKD-sized paper is obtained by next two mechanism: 1) formation of a thin-layer of AKD on the fiber surface through melting and spreading of AKD emulsion particles by heat and 2) the hydrolysis of AKD to dialkyl ketone which has higher melting point, during drying and storage of AKD sized papers.

• 한국지반공학회논문집
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• 제20권6호
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• pp.109-118
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• 2004

점토의 압밀은 시간적 지연을 갖는 현상으로 시간적 지연은 소성적 지연시간과 수리적 지연시간으로 나눠진다. 본 연구에서는 점토의 2차압밀이 압밀침하에 어떠한 영향을 미치는지를 알고자 CRS 시험을 실시하였다. 시험결과 소성적 지연시간은 선행압밀하중을 구하는데 큰 영향을 미치는 것으로 나타났고, 압밀하중과 압밀지연시간으로부터 유사선행압밀하중을 예측하는 식을 제안하였다. 또 압밀지연시간에 따른 압밀계수의 특징은 선행압밀 전까지는 큰 범위의 값을 가지나 선행압밀하중의 약 2배 지점을 지나서는 압밀지연시간에 관계없이 일정한 값으로 수렴하는 경향을 나타냈다. 그리고 정규압밀영역에서의 투수계수는 간극비와 밀접한 관계에 있으며, Samarasinghe 등의 제안식을 이용하여 시험결과로부터 투수상수 n, $C_1$값을 결정하였고, Kozeny-Carman 제안식과 비교분석하여 보았다. 투수계수와 간극비 관계에서도 압밀지연시간에 의한 지연압축으로 인하여 aging effect를 관찰할 수 있었다.

• 전기학회논문지
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• 제63권6호
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• pp.764-769
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• 2014

This paper describes sheath voltage limiter(SVL) transient characteristics by switching overvoltage considering single point bonding in underground transmission cables. The crossbonding system is generally used for grounding methods of underground transmission system. However, the single point bonding system is used in selective area which is difficult to consist of crossbonding major section. The sheath voltage limiters are connected between joints in the single point bonding. Specially, the high overvoltage might be generated in that section as well as the aging of sheath voltage limiter might be progressed by various electrical stress including lightning overvoltage, switching overvoltage and power frequency overvoltage. Therefore, in this paper, the switching overvoltage characteristics in underground cables are firstly analysed using EMTP simulation. Then, the switching overvoltage of sheath voltage limiter is also studied in single point bonding. Finally, the reduction method of sheath voltage limiter switching overvoltage is proposed by various simulation studies including circuit breaker operating order.

• 한국실내디자인학회논문집
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• 제19권2호
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• pp.225-233
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• 2010

At this point in time South Korea is rapidly metastasizing to a aging society. A major cause of aging can be summarized as increased life expectancy, decrease of nuclear family and birthrate, and South Korea's progress is faster than any other country. From the 1970s, western society has changed social welfare to deinstitutionalization and community care because of problems about economic reason and facilities protection, so the type of elderly social service has also changed from the facility welfare service which is accommodated old people in certain facility to community welfare service which provides various welfare services with living together. Public facilities for low income group which are supported by government are lower, 6.6%, than the United States or Japan, 50%. They are divided into private manage facilities and subscription elderly facilities. These subscription elderly residential facilities show poor administration because of focusing on development and market analysis for investment returns. Therefore, in order to vitalize the elderly welfare residential facilities in Korea, we need plans about systematic services facilities for welfare and phased medical treatments. Therefore, the purpose of this study is that (1) the types and functions of residents for community elderly residential facilities in elderly welfare policies of U.S., and supported policies are researched as a transcendental model, (2) data about operating system with the principles of the market is analyzed, and (3) basic data about welfare facility plan for community residential elderly people is provided.

• 전기학회논문지
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• 제67권1호
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• pp.142-147
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• 2018

Private electrical facilities are judged whether it is suitable for the insulation aging condition of their incoming underground cables using DC leakage current test method. In the case where the service point of utility is the secondary side of cut out switch installed in the electric pole, there is a problem that it is difficult to separate the lightning arresters(LA) because of their high position of the pole. Therefore, the field test voltage is applied at value lower than DC 30 kV, which are stated in the inspection guideline. However, this test could reduced the insulation performance of the LA by accelerating the electrical stress of the metal oxide varistor element in the pre-breakdown region. In this study, we analyzed the relationship between the DC test voltage and the leakage current using the non-destructive DC high voltage equipment with leakage current measurement function. The results show that the leakage current increases sharply above the specified test voltage. As a consequence, it could be contributed to improve insulation aging inspection method by selecting the possible test area on the VI characteristic curve of the pre-breakdown area of the LA.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제15권4호
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• pp.33-43
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• 2009

As a result of rapid aging speed in our society, many problems related to elderly people have happened in many parts of our society. Among them, supply for elderly housing is one of the biggest problems. To solve these problems, 'long-term care insurance' has been put in operation from July 2008. By the time of the insurance operation, Ministry of Health and Welfare is increasing facilities every year according to '10-year expending plan of Care service infra' from 2002. As a result, the supply rate of elderly facilities has been raised. But the differences of facility supply rate between regions are very high in some cases. Therefore older people who need care sometimes cannot get proper care services in some areas. In that case, the frail older people have to use other care facilities of other regions. This is not a proper situation from the point of "Aging in Place". In order to prevent that case, it is necessary to set up proper 'Daily Living Spheres' and establish elderly care plan for it. Considering the points above, this study proposes the size of 'Daily Living Spheres' for the elderly, the kind and amount of elderly care facilities in it for the construction of Community Based Elderly Care System.

• 한국주조공학회지
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• 제7권2호
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• pp.114-121
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• 1987

In order to determine the plane strain fracture toughness of Al-Si-Cu-Mg alloy castings, solution heat treatments have been conducted at $530^{\circ}C$ for 8hr and aged for 10hr at $145^{\circ}C$, $160^{\circ}C$ and $175^{\circ}C$. Effects of aging treatment and of Si contents on the fracture toughness have been investigated by a three point loaded bend test, using the artificial notch. The results obtained are as follows; 1) The fracture toughness is appreciably affected by the aging treatment temperature and Si contents. The specimen aged for 10hr at $145^{\circ}C$ has the highest fracture toughness. 2) Increasing Si contents from 5% to 9% results in decrease of fracture toughness. 3) Increasing the aging temperature and Si contents, C.O.D. value was decreased. The specimen aged for 10hr at $145^{\circ}C$ has the highest C.O.D. value. 4) Dimple patterns were observed in the specimens of containing under 7% Si, while mixed cleavage-dimple patterns in those of over 8% Si.

• The Korean journal of internal medicine
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• 제33권6호
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• pp.1039-1049
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• 2018

The populations of Asian countries are expected to age rapidly in the near future, with a dramatic increase in the number of heart failure (HF) patients also anticipated. The need for palliative and end-of-life care for elderly patients with advanced HF is currently recognized in aging societies. However, palliative care and active treatment for HF are not mutually exclusive, and palliative care should be provided to reduce suffering occurring at any stage of symptomatic HF after the point of diagnosis. HF patients are at high risk of sudden cardiac death from the early stages of the disease onwards. The decision of whether to perform cardiopulmonary resuscitation in the event of an emergency is challenging, especially in elderly HF patients, because of the difficulty in accurately predicting the prognosis of the condition. Furthermore, advanced HF patients are often fitted with a device, and device deactivation at the end of life is a complicated process. Treatment strategies should thus be discussed by multi-disciplinary teams, including palliative experts, and should consider patient directives to address the problems discussed above. Open communication with the HF patient regarding the expected prognosis, course, and treatment options will serve to support the patient and aid in future planning.

• 문화기술의 융합
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• 제1권1호
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• pp.69-72
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• 2015

최근 한국에서 저출산, 핵가족화, 1인 가족 증가 등의 사회적 병리 현상과 더불어 고령화가 급속히 진행되고 있다. 한국의 고령화 추이는 일본의 고령화 추이와 유사하게 나타나고 있어, 향후 더 심화된 고령화가 나타날 것으로 보인다. 그러나 한국은 아직 고령화 문제에 대한 연구가 매우 부족하여 향후 고령화가 급속도로 진행시 많은 문제가 발생할 것으로 예상된다. 이에 고령화에 대해 대비하고 있는 일본의 장례문화 중 한국의 장례에 도입할 수 있는 적합한 문화를 비교하여 고령화에 맞춰 대비할 필요가 있다. 일본의 고령화에 따라 나타나는 장례문화는 슈카츠(終活), 직장(直葬), 가족장(家族葬) 등이 있다. 이 중, 핵가족화 및 1인 가족 증가 등에 따른 소규모 장례문화가 확산될 것으로 예상되어 일본의 '가족장(家族葬)'이 한국에 도입하기에 적합할 것으로 보인다. 급속히 고령화되어가는 한국 사회와 고령화에 따른 변화된 장례문화의 제시는 필수적이며, '가족장(家族葬)' 제도의 도입은 향후 발생할 한국 내의 고령화에 따른 장례문화를 선도하는데 중요한 지침이 될 것으로 기대한다.

• 한국가족복지학
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• 제54호
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• pp.187-224
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• 2016

본 연구의 목적은 심리사회적노화가 연령통합인식에 미치는 영향을 살펴보고, 이에 대한 가족주의 및 가족결속의 조절효과를 확인하는 것이다. 이를 통해 연령통합을 위한 가족 차원의 실천적 정책적 개입 근거의 기초자료를 마련했다는 점에서 의의가 있다. 본 연구에서 사용된 자료는 한국연구재단의 지원을 받아 진행된 "2014년 고령화 사회에 대한 인식조사"이며, 40세부터 90세까지 702명의 자료를 활용하여 분석하였다. 결과분석은 STATA13.1 통계프로그램을 활용하여, 다중회귀분석을 실시하였다. 분석결과 심리사회적 노화인식이 낮을수록 연령통합인식이 부정적인 것으로 나타났다. 가족주의와 가족결속은 연령통합인식에는 통계적으로 유의하게 영향을 주지 않았지만, 심리사회적 노화와 상호작용하여 연령통합인식을 상승시키는 조절효과가 통계적으로 유의하게 나타났다. 즉, 심리사회적 노화가 부정적이며, 연령통합인식을 감소시킬 때, 가족중심적인 사고와 실제적인 가족 간 교류와 결속은 연령통합인식을 상승시키는 순수조절효과를 나타내었다. 본 연구를 통해 심리사회적 노화가 부정적인 시점에서 가족중심의 가치와 가족 간 교류와 결속을 강화하는 것이 연령통합인식에 긍정적으로 기여할 수 있다는 시사점을 제공하였다.