• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
• /
• pp.17-22
• /
• 2002

Chloride ions have a tendency to penetrate into concrete and proceed the corrosion by depassivating rebar surface. Thus the deteriorated concrete is subject to experience severe degrading of durability under marine environment. Physical properties of mortar, such as, compressive strength and penetration depth of chloride ion were investigated. And to investigate the effect of containing SG, FA in mortar, the diffusion coefficient of chloride was measured through an electro - migration test. The diffusion coefficient of chloride was decreased with the increase of replacement ratio of SG compared with plain specimen.

• 한국지역지리학회지
• /
• 제11권2호
• /
• pp.169-186
• /
• 2005

본 연구에서는 서울시에서 발생하고 있는 인구이동의 대부분을 차지하는 도시내 인구이동의 지리적 특성을 밝히고, 아파트 평당 매매가를 통해 지역의 경제적 특성이 인구이동에 미치는 영향을 살펴보고자 한다. 구와 행정동을 분석단위지역으로 인구이동을 가시화함으로써 밝혀진 서울시 내부 인구이동의 지리적 특성은 다음과 같다. 첫째, 거리가 증가함에 따라 인구이동은 급격하게 감소하였는데, 지배적인 인구이동은 대부분 인접 구와 인접 행정동 사이에서 발생함으로써 근거리이동이 탁월하게 관찰되었다. 둘째, 근거리이동의 지배적인 패턴은 인접한 모든 지역이 아니라 특정 지역 사이에서 관찰되는데, 특히 한강과 학군이 주요한 경계로 나타나고 있다. 섯째, 분석 단위지역에 따라 상이한 인구이동 패턴이 나타나고 있다. 이와 동시에 행정동별 아파트 평당 매매가의 차이는 인구이동의 발생 및 이동인구의 규모에 큰 영향을 미치고 있다. 따라서 서울시 내부 인구이동의 지리적 특성인 근거리이동은 거리가 인구이동에 미치는 영향력을 의미하는 동시에, 인접한 지역 간의 경제적 유사성 및 주택시장의 분절화에 따른 인구이동에 있어서의 제약을 반영한다. 이는 서울시 내부의 인구이동이 주택가격이 상이한 지역에 거주하는 집단사이의 거주지 분리를 유지 강화시키는 역할을 하고 있음을 시사한다.

• 한국교육학연구
• /
• 제14권1호
• /
• pp.45-69
• /
• 2008

본 연구는 한국교육고용패널(KEEP) 데이터를 사용하여 한국사회에서 발생하는 대안교육 수요의 결정요인을 분석하였다. 분석결과에 따르면, 자녀의 성별과 컴퓨터 이용 시간이 학부모의 대안교육 수요에 중요한 영향을 미치는 것으로 나타났다. 또한 교육정책에 대해 관심이 크고, 학교만족도가 낮으며, 교육 목적의 탈한국 성향이 강한 학부모일수록 자녀에게 대안교육을 제공하려는 생각이 강한 것으로 밝혀졌다. 그런데 대안교육 수요는 자녀의 성별에 따라 다소 다른 양상을 보여주었다. 그리하여 남학생에게는 컴퓨터 이용 시간과 교육정책에 대한 관심이 주로 문제가 될 수 있는 반면, 여학생의 경우에는 건강상태가 대안교육 수요를 유발할 개연성이 있는 것으로 드러났다. 한편 학부모의 학교만족도와 교육 목적의 탈한국 성향은 남학생과 여학생 모두에게 대안교육 수요의 핵심적 결정요인으로 작용하고 있었다.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
• /
• pp.125-126
• /
• 2005

Recently semiconductor devices are required more smaller scale and more powerful performance. For smaller scale of device, multilayer structure is proposed. And, for the higher performance, interconnection material is change to copper, because copper has high EM(Electro-migration)and low resistivity. Then copper CMP process is a great role in a multilayer formation of semiconductor. Copper process is different from aluminum process. ECP process is one of the copper processes. In this paper, we focused on the defects tendency by copper thickness which filled using ECP process. we observed hump high and dishing. Conclusively, hump hight reduced at copper thickness increased Also dishing reduced.

• Environmental Engineering Research
• /
• 제14권4호
• /
• pp.226-236
• /
• 2009

The performance of phytoremediation has proven effective in the removal of nutrients and metals from aqueous systems. However, little information is available regarding the behavior of pesticides and their removal pathways in aquatic environments involving plant-uptake. A detailed understanding of the kinetics of pesticide removal by plants and information on compound/plant partition coefficients can lead to an effective design of the phytoremediation process for anthropogenic pesticide reduction. It was determined that the reduction rates of four organophosphorus (OP) and two organochlorine (OC) pesticides (diazinon, fenitrothion, malathion, parathion, dieldrin, hexachlorobenzene [HCB]) could be simulated by first-order reaction kinetics. The magnitude of k was dependent on the pesticide species and found within the range of 0.409 - 0.580 $d^{-1}$. Analytical results obtained by mass balances suggested that differential chemical stability, including diversity of molecular structure, half-lives, and water solubility, would greatly influence the removal mechanisms and pathways of OPs and OCs in a phytoreactor (PR). In the case of OP pesticides, plant accumulation was an important pathway for the removal of fenitrothion and parathion from water, while pesticide sorption in suspended matter (SM) was an important pathway for removal of dieldrin and HCB. The magnitude of the pesticide migration factor (${\Large M}_p^{pesticide}$) is a good indication of determining the tendency of pesticide movement from below- to above-ground biomass. The uncertainties related to the different phenomena involved in the laboratory phyto-experiment are also discussed.

• 대한수의학회지
• /
• 제33권4호
• /
• pp.679-691
• /
• 1993

As a series of studies to investigate the effect of immunosuppression on Ascaris suum infection in undefinitive hosts, a delicate relationship between host and parasite, rabbits were divided into experiment 1(control group) and experiment 2(immnunosuppressive group treated with prednisolone acetate) and inoculated with a single dose of 5,000 embryonated A suum eggs. The recovery rates, sizes and morphology of the larvae and immunological responses in the rabbits were chronologically monitored according to somatic migration. In both experiments, the larvae failed to develop into the adults, but young adults in the experiment 2 grew somewhat faster and survied later than those in the experiment 1. The mast cells of small intestinal mucosa and mesenteric lymph nodes and the goblet cells of small intestinal mucosa in the worm detected cases of experiment 2 decreased remarkably in number comparing with those of experiment 1. Considering the experimental results. the expulsion mechanism of somatic migrant larvae may he related to the temporary increasing tendency of the mast cells, the goblet cells, T-cells of mesenteric lymph nodes and spleens, eosinophils in peripheral blood, degranulation rates of peritoneal mast cells and the migration inhibition rates of leucocytes. In addition, patent infection of A suum in the rabbits was not obviously observed despite of immunosuppression by prednisolone acetate.

• 동남아시아연구
• /
• 제20권2호
• /
• pp.31-72
• /
• 2010

This study is to explain the nature of transnational activities being involved in by Filipina intermarriage migrants in Korea by examining the institutional backgrounds of market, society and the state. The increasing number of Filipina intermarriage with Korean coincides with the advance of liberal market economy, which governs internal and bilateral interactions between and among the three institutions in both countries. While existing various reasons for engaging in intermarriage, a significant number of Filipina wives in Korea ventured into it with uncertain expectations that they might earn better lives and could support their families. Such hopes usually turn out in vain when they meet the real lives in Korea. It is mainly because their spouses in Korea would rather be those who left behind in the marriage market due to their lack of competitiveness. Filipina wives are also suffering from social isolation caused by language and other barriers such as family relations or rural life they might settle in. Their transnational activities usually tend to be their effort to breakthrough their unexpected condition of difficult lives in Korea. They usually make use of transnational sort of community activities to cultivate chances to engage in bread earning activity. Migrant's transnational activity has a great impact on sociocultural changes in the country of origin and of arrival. Transnational activity provides migrants with economic opportunities, and uplifts self-esteem as well. Intermarriage couples, especially with Southeast Asian wives, and their offsprings show a tendency of downward assimilation to Korean society. Korean state policy toward them should not simply apply undiscriminated assimilation theory, but take into account their possible strength of transnational identity with which they could find a means to integrate themselves successfully into the mainstream Korean society.

• Journal of Radiation Protection and Research
• /
• 제44권4호
• /
• pp.128-148
• /
• 2019

Massive environmental monitoring has been conducted continuously since the Fukushima Daiichi Nuclear Power accident in March of 2011 by different monitoring methods that have different features together with migration studies of radiocesium in diverse environments. These results have clarified the characteristics of radiological environments and their temporal change around the Fukushima site. At three months after the accident, multiple radionuclides including radiostrontium and plutonium were detected in many locations; and it was confirmed that radiocesium was most important from the viewpoint of long-term exposure. Radiation levels around the Fukushima site have decreased greatly over time. The decreasing trend was found to change variously according to local conditions. The air dose rates in environments related to human living have decreased faster than expected from radioactive decay by a factor of 2-3 on average; those in pure forest have decreased more closely to physical decay. The main causes of air dose rate reduction were judged to be radioactive decay, movement of radiocesium in vertical and horizontal directions, and decontamination. Land-use categories and human activities have significantly affected the reduction tendency. Difference in the air dose rate reduction trends can be explained qualitatively according to the knowledge obtained in radiocesium migration studies; whereas, the quantitative explanation for individual sites is an important future challenge. The ecological half-lives of air dose rates have been evaluated by several researchers, and a short-term half-life within 1 year was commonly observed in the studies. An empirical model for predicting air dose rate distribution was developed based on statistical analysis of an extensive car-borne survey dataset, which enabled the prediction with confidence intervals. Different types of contamination maps were integrated to better quantify the spatial data. The obtained data were used for extended studies such as for identifying the main reactor that caused the contamination of arbitrary regions and developing standard procedures for environmental measurement and sampling. Annual external exposure doses for residents who intended to return to their homes were estimated as within a few millisieverts. Different forms of environmental data and knowledge have been provided for wide spectrum of people. Diverse aspects of lessons learned from the Fukushima accident, including practical ones, must be passed on to future generations.

• 한국농촌건축학회논문집
• /
• 제4권1호
• /
• pp.9-18
• /
• 2002

Keumsan-gun is the area where there are many mobile populations as the place to be adjacent to Daejon. There is the tendency that the empty houses at Keumsan area are increasing as 1,115 houses every year as of 2001. So, this researcher examined and analyzed the actual state by grasping the present situation of empty houses centering around Keumsan-gun. And, this researcher could obtain the following conclusion as the result that this researcher progressed the study so as to present the application scheme of empty houses. As for Keumsan-gun, farming populations are more than other city and gun at Choongcheong Southern Proince Area as the area formed with mountain groups topographically. Thus, it is forecast that the appearance of empty houses will increase, as the population decrease and the residents to have migration plan will appear higher than other city and gun in the future also. Therefore, as for the superannuated empty houses that use is impossible, to service by removing will be helpful to the image uplifting of village. In addition, as for the empty houses that use is possible, the establishment of system to connect buyers by rebuilding them as garden houses and weekend houses etc. through purchase and sale and long-term lease etc. is necessary.

• Asian Pacific Journal of Cancer Prevention
• /
• 제16권2호
• /
• pp.831-836
• /
• 2015

Tumor fluid accumulation occurs in both human cancer and experimental tumor models. Solid tumors show a tendency to tumor fluid accumulation because of their anatomical and physiological features and this may be influenced by molecular factors. Fluid accumulation in the peri-tumor area also occurs in the Dunning model of rat prostate cancer as the tumor grows. In this study, the effects of tumor fluids that were obtained from Dunning prostate tumor-bearing Copenhagen rats on the strongly metastatic MAT-LyLu cell line were investigatedby examining the cell's migration and tumor fluid's toxicity and the kinetic parameters such as cell proliferation, mitotic index, and labelling index. In this research, tumor fluids were obtained from rats injected with $2{\times}10^5$ MAT-LyLu cells and treated with saline solution, and 200 nM tetrodotoxin (TTX), highly specific sodium channel blocker was used. Sterilized tumor fluids were added to medium of MAT-LyLu cells with the proportion of 20% in vitro. Consequently, it was demonstrated that Dunning rat prostate tumor fluid significantly inhibited proliferation (up to 50%), mitotic index, and labeling index of MAT-LyLu cells (up to 75%) (p<0.05) but stimulated the motility of the cells in vitro.