• Title/Summary/Keyword: 설계특성변화

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Analysis of the Effect of Heat Island on the Administrative District Unit in Seoul Using LANDSAT Image (LANDSAT영상을 이용한 서울시 행정구역 단위의 열섬효과 분석)

  • Lee, Kyung Il;Ryu, Jieun;Jeon, Seong Woo;Jung, Hui Cheul;Kang, Jin Young
    • Korean Journal of Remote Sensing
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    • v.33 no.5_3
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    • pp.821-834
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    • 2017
  • The increase in the rate of industrialization due to urbanization has caused the Urban Heat Island phenomenon where the temperature of the city is higher than the surrounding area, and its intensity is increasing with climate change. Among the cities where heat island phenomenon occurs, Seoul city has different degree of urbanization, green area ratio, energy consumption, and population density in each administrative district, and as a result, the strength of heat island is also different. So It is necessary to analyze the difference of Urban Heat Island Intensity by administrative district and the cause. In this study, the UHI intensity of the administrative gu and the administrative dong were extracted from the Seoul metropolitan area and the differences among the administrative districts were examined. and linear regression analysis were conducted with The variables included in the three categories(weather condition, anthropogenic heat generation, and land use characteristics) to investigate the cause of the difference in heat UHI intensity in each administrative district. As a result of analysis, UHI Intensity was found to be different according to the characteristics of administrative gu, administrative dong, and surrounding environment. The difference in administrative dong was larger than gu unit, and the UHI Intensity of gu and the UHI Intensity distribution of dongs belonging to the gu were also different. Linear regression analysis showed that there was a difference in heat island development intensity according to the average wind speed, development degree, Soil Adjusted Vegetation Index (SAVI), Normalized Difference Built-up Index (NDBI) value. Among them, the SAVI and NDBI showed a difference in value up to the dong unit and The creation of a wind route environment for the mitigation of the heat island phenomenon is necessary for the administrative dong unit level. Therefore, it is considered that projects for mitigating heat island phenomenon such as land cover improvement plan, wind route improvement plan, and green wall surface plan for development area need to consider administrative dongs belonging to the gu rather than just considering the difference of administrative gu units. The results of this study are expected to provide the directions for urban thermal environment design and policy development in the future by deriving the necessity of analysis unit and the factors to be considered for the administrative city unit to mitigate the urban heat island phenomenon.

Effects of Steam Flaking of Corns imported from USA and India on the in vitro Fermentation Characteristic and the Mycotixin Contents of Logistic Processing Line (미국산과 인도산 옥수수의 steam flaking 처리가 공정라인별 mycotoxin 함량의 변화와 in vitro 발효 특성에 미치는 영향)

  • Lee, Shin-Ja;Lee, Ji-Hun;Shin, Nyeon-Hak;Han, Jung-Hun;Hyun, Jong-Hwan;Moon, Yea-Hwang;Lee, Sung-Sill
    • Journal of Life Science
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    • v.19 no.1
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    • pp.65-74
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    • 2009
  • The objective of this study was to examine the effects of steam flaking treatment of corn grains imported from USA and India on in vitro gas production, microbial growth and contents of aflatoxin $B_1$ and ochratoxin A. Each treatment was composed of total 4 treatments including (1) USCW (US com-whole type), (2) USCF (US corn-flaked type), (3) IDCW (India corn-whole type) and (4) IDCF (India orn-flaked type) with 4 replications $\times$ 6 incubation times (3, 6, 9, 12, 18 and 24 hr). Mycotoxin (aflatoxin $B_1$ & ochratoxin A) contents in test corns tended to increase gradually with increasing logistics periods from the harbor, hopper, silo to processing line. The contents of aflatoxin $B_1$ in India corn (IDCW) and US corn (USCW) were 11.71 and 1.78 ppb, respectively when measured at the hopper. After steam flaking, both contents of aflatoxin $B_1$ in USCW and IDCW were 0.00 ppb. It means that Aspergillus flavus could be decreased by steam flaking. However, this trend was not observed in ochratoxin content. The gas production rate of USA corns (USCW & USCF) was significantly (p<0.05) higher than India corns (IDCW & IDCF), and that of steam flaked corns (USCF & IDCF) was higher $1.5{\sim}2%$ than whole corns (USCW & IDCW) after 3 hr incubation in in vitro experiment. pH value was optimally maintained for microbial growth during whole incubation times with the value of 6.05 to 6.54, and was not significantly different between treatments, but USCF was somewhat lower than other treatments. pH value decreased following 12 hr of incubation but gas production increased rapidly during the same period. In addition, in vitro microbial growth rates also increased with up to 18 hr of incubation period, thereafter experienced a decrease with extended incubation time. In conclusion, US corn was superior to India corn by origin based on the results of in vitro and mycotoxin contents. And steam flaking process of imported corns tended to decrease mycotoxin contents such as aflatoxin $B_1$ and ochratoxin A as well as improve in vitro gas production and microbial growth rates.

Fundamental Study on Establishing the Subgrade Compaction Control Criteria of DCPT with Laboratory Test and In-situ Tests (실내 및 현장실험를 통한 DCPT의 노상토 다짐관리기준 정립에 관한 기초연구)

  • Choi, Jun-Seong
    • International Journal of Highway Engineering
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    • v.10 no.4
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    • pp.103-116
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    • 2008
  • In this study, in-situ testing method, Dynamic Cone Penetration Test(DCPT) was presented to establish a new compaction control criteria with using mechanical property like elastic modulus instead of unit weight for field compaction control. Soil chamber tests and in-situ tests were carried out to confirm DCPT tests can predict the designed elastic modulus after field compaction, and correlation analysis among the DCPT, CBR and resilient modulus of sub grade were performed. Also, DCPT test spacing criteria in the construction site was proposed from the literature review. In the result of laboratory tests, Livneh's equation was the best in correlation between PR of DCPT and CBR, George and Pradesh's equation was the best in the predicted resilient modulus. In the resilient modulus using FWD, Gudishala's equation estimates little larger than predicted resilient modulus and Chen's equation estimates little smaller. And KICT's equation estimates the modulus smaller than predicted resilient modulus. But using the results of laboratory resilient modulus tests considering the deviatoric and confining stress from the moving vehicle, the KICT's equation was the best. In the results of In-situ DCPT tests, the variation of PR can occur according to size distribution of penetrate points. So DCPT test spacing was proposed to reduce the difference of PR. Also it was shows that average PR was different according to subgrade materials although the subgrade was satisfied the degree of compaction. Especially large sized materials show smaller PR, and it is also found that field water contents have influence a lot of degree of compaction but a little on the average PR of the DCPT tests.

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Patterns of Cash Payments for Care : Cross-National Comparative Study (장기요양 현금급여 정책의 국가간 비교 연구)

  • Seok, Jae-Eun
    • Korean Journal of Social Welfare
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    • v.58 no.2
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    • pp.273-302
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    • 2006
  • The introduction of cash payments for care is a distinct trend that characterizes changes in care policies since the 1990s. Recently, many developed countries have newly introduced or extended cash payments for care that allow care users to be able to plan themselves for their cares instead of receiving direct care services from the state. Cash payments for care can be said to be one of the alternative policies by which user choices are extended, and it becomes possible to establish demand-cantered care delivery systems more economically and effectively, hence addressing the issue of the financial limitations and rigid systems that are common in modern welfare states, which make it difficult to response to various needs. However, the design and administration of cash for care vary across different countries. Such variations of cash for care policies influence on the combination of consumerism (based on liberal market values intrinsic in the care market) and citizenship based on social solidarity. Those variations eventually produce impacts on the balance of responsibilities and the roles of families, the state and market regarding care in other words, balancing of welfare pluralism. This paper has attempted to find general meanings and particularity of cash for care polices in modem welfare states by means of looking at the characteristics of cash for care policies of four different countries (Netherlands, France, Germany and Italy) and their impacts on their care market. If the four countries are ranked by the degree that they emphasize citizenship in light with social rights, the Netherlands, France, Germany and Italy could be placed in due order. From an economic point of view and in terms of cost containment, those countries will be placed in an inverse order, It is apparent that in the course of planting cash for care policies in the existing social systems involving different socio-cultural conditions and labour markets, sometimes more emphasis is placed on the citizenship of care users, family carers and care providers than on cost containment issue, and sometimes vice versa. Behind this lies the process of different social valuation on what care is about; who can better deliver care; who should be responsible for care; how responsibilities should be shared and so on.

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Numerical and Experimental Study on the Coal Reaction in an Entrained Flow Gasifier (습식분류층 석탄가스화기 수치해석 및 실험적 연구)

  • Kim, Hey-Suk;Choi, Seung-Hee;Hwang, Min-Jung;Song, Woo-Young;Shin, Mi-Soo;Jang, Dong-Soon;Yun, Sang-June;Choi, Young-Chan;Lee, Gae-Goo
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.2
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    • pp.165-174
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    • 2010
  • The numerical modeling of a coal gasification reaction occurring in an entrained flow coal gasifier is presented in this study. The purposes of this study are to develop a reliable evaluation method of coal gasifier not only for the basic design but also further system operation optimization using a CFD(Computational Fluid Dynamics) method. The coal gasification reaction consists of a series of reaction processes such as water evaporation, coal devolatilization, heterogeneous char reactions, and coal-off gaseous reaction in two-phase, turbulent and radiation participating media. Both numerical and experimental studies are made for the 1.0 ton/day entrained flow coal gasifier installed in the Korea Institute of Energy Research (KIER). The comprehensive computer program in this study is made basically using commercial CFD program by implementing several subroutines necessary for gasification process, which include Eddy-Breakup model together with the harmonic mean approach for turbulent reaction. Further Lagrangian approach in particle trajectory is adopted with the consideration of turbulent effect caused by the non-linearity of drag force, etc. The program developed is successfully evaluated against experimental data such as profiles of temperature and gaseous species concentration together with the cold gas efficiency. Further intensive investigation has been made in terms of the size distribution of pulverized coal particle, the slurry concentration, and the design parameters of gasifier. These parameters considered in this study are compared and evaluated each other through the calculated syngas production rate and cold gas efficiency, appearing to directly affect gasification performance. Considering the complexity of entrained coal gasification, even if the results of this study looks physically reasonable and consistent in parametric study, more efforts of elaborating modeling together with the systematic evaluation against experimental data are necessary for the development of an reliable design tool using CFD method.

Flow Resistance of Plane Nettings for Net Cages (우리 그물용 평면 그물감의 유수저항)

  • KIM Tae-Ho;KIM Dae-An;RYU Cheong-Ro
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.3
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    • pp.254-259
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    • 2001
  • In order to make clear the resistance of plane nettings u,sed widely in constructing net cages, the resistance R taken by $R=kSU^2$, where S was the wall area of nettings, U the flow velocity, and k the resistance coefficient, was measured in a circulating water channel by using nylon Raschel nettings and PE trawler-knotted nettings coated with anti-fouling paint or not and then the properties of coefficient k were investigated. The mesh size L and the angle $\phi$ between two adjacent bars was given by the function of Reynolds number ${\lambda}U/v$ in the region of ${\lambda}U/v<180$, i. e., $$k=350(\frac{\lambda U}{v})^{-0.25}$$.where $\lambda$ was the representative size of nettings expressed as $$\lambda=\frac{{\pi}d^2}{2L\;sin\;2{\phi}}$$On the other hand, the coefficient k was almost fixed between 92 and 102 ($kg{\cdot}s^2/m^4$) in the region of ${\lambda}U/v{\geq}180$ and varied according to the ratio $S_n/S$ of the total area $S_n$ of nettings projected to the plane perpendicular to the water flow to the wall area S of nettings, i.e., it was given by $$k=98.6(\frac{S_n}{S})^{1.19}$$ regardless of the coating of paint.

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The Effects of Musculoskeletal Disorder Prevention Exercise Program Considering Agricultural Work Posture (농작업 자세를 고려한 근골격계 질환 예방 운동프로그램의 효과)

  • Park, So-Yeon;Kim, Jin-Kyung
    • The Journal of Korean society of community based occupational therapy
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    • v.3 no.1
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    • pp.1-10
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    • 2013
  • Objective : This study investigates the impact of the musculoskeletal disorder prevention exercise program designed on the basis of agricultural work posture on the balance ability, Oswestry Disability level, and Psychosocial stress of participants from one rural village in Chungnam area. Method : The exercise program was provided to 21 farmers with musculoskeletal symptoms living in one village in Chungnam area. Such program was performed once a week, 90 minutes per session, for a total of twelve weeks from July 10 to October 11, 2008, and was constructed in a way to increase flexibility and muscular strength, taking agricultural work posture into account. The balance ability, Oswestry Disability Index, and Psychosocial Well-being Index scores were analyzed based on the data of 13 of the farmers who participated in the program for more than eight times and in all of the pre- and post-assessments. Result : Thirteen participants were all women who were 70.55(${\pm}6.78$) years old on average. Most of them were engaged in general dry-filed farming. The parts where they mainly felt the pain were low back(69.2%) and knees(61.5%), and 46.2% responded 'not healthy' to the question on the overall health status. The static balance ability when standing on the right foot significantly increased from the average 9.27(${\pm}5.53$) seconds before intervention to 14.22(${\pm}5.47$) seconds after intervention(p<.05). The Oswestry Disability Index showed a significant change, decreasing from the average 19.84(${\pm}6.89$) seconds to 14.38(${\pm}7.58$) seconds(p<.05). However, there was no change in the Psychosocial Well-being Index. Conclusion : This exercise program that has been conducted for the female farmers who are mainly engaged in the dry-filed farming has contributed to the improvement of their static ability and reduction of their Oswestry Disability Index scores. It is expected that the studies on the effects of the differentiated exercise programs depending on work characteristics will make progress in the future.

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Study on Hydrogen Production and CO Oxidation Reaction using Plasma Reforming System with PEMFC (고분자 전해질 연료전지용 플라즈마 개질 시스템에서 수소 생산 및 CO 산화반응에 관한 연구)

  • Hong, Suck Joo;Lim, Mun Sup;Chun, Young Nam
    • Korean Chemical Engineering Research
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    • v.45 no.6
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    • pp.656-662
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    • 2007
  • Fuel reformer using plasma and shift reactor for CO oxidation were designed and manufactured as $H_2$ supply device to operate a polymer electrolyte membrane fuel cell (PEMFC). $H_2$ selectivity was increased by non-thermal plasma reformer using GlidArc discharge with Ni catalyst simultaneously. Shift reactor was consisted of steam generator, low temperature shifter, high temperature shifter and preferential oxidation reactor. Parametric screening studies of fuel reformer were conducted, in which there were the variations of the catalyst temperature, gas component ratio, total gas ratio and input power. and parametric screening studies of shift reactor were conducted, in which there were the variations of the air flow rate, stema flow rate and temperature. When the $O_2/C$ ratio was 0.64, total gas flow rate was 14.2 l/min, catalytic reactor temperature was $672^{\circ}C$ and input power 1.1 kJ/L, the production of $H_2$ was maximized 41.1%. And $CH_4$ conversion rate, $H_2$ yield and reformer energy density were 88.7%, 54% and 35.2% respectively. When the $O_2/C$ ratio was 0.3 in the PrOx reactor, steam flow ratio was 2.8 in the HTS, and temperature were 475, 314, 260, $235^{\circ}C$ in the HTS, LTS, PrOx, the conversion of CO was optimized conditions of shift reactor using simulated reformate gas. Preheat time of the reactor using plasma was 30 min, component of reformed gas from shift reactor were $H_2$ 38%, CO<10 ppm, $N_2$ 36%, $CO_2$ 21% and $CH_4$ 4%.

Family Structure and Succession of the Late Chosun Seen through Male Adoption (양자제도를 통해 본 조선후기 가족구조와 가계계승: 의성김씨 호구단자 분석을 중심으로)

  • Park, Soo-Mi
    • Korea journal of population studies
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    • v.30 no.2
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    • pp.71-95
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    • 2007
  • This paper attempts to identify the principle of family succession and family patterns of yangban in the late Chosun period through an analysis of male adaptation cases found in family registration records. The primary source of analysis is the family registration documents of Uiseong Kim's from the late 17th century to the early 20th century. As a result, it is found that there is a substantial change in the patterns of family from the early and mid Chosun period to the late Chosun period. The change is the strengthening of the principle of patriarchy succession through male adoption. Looking at the data as a whole, the average number of household members is increased and the membership of kinship also expanded. In contrast to the family patterns of the early Chosun period, not only the patterns of Uiseong Kim's family are predominately immediate family or collateral family but also the majority is extended family in the 18th and 19th centuries. The male adoption cases recorded in Uiseong Kim's family registration documents take up 33.8% of the male adoption cases in the entire family registration documents. This goes to show that the strengthening of the principle of primogeniture succession at a time when child mortality rate is very high resulted in the increase of male adoption. In conclusion, the late Chosun society was a society where the seat of primogeniture was much more important than immediate hereditary members in the family succession.

Effect of moisture content on some physical properties of domestic wheat (함수율에 따른 우리밀의 물리적 특성)

  • Kim, Oui-Woung;Kim, Hoon;Kim, Sang-Suk;Choi, Eun-Jung
    • Food Science and Preservation
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    • v.22 no.5
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    • pp.652-659
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    • 2015
  • The physical properties of wheat kernels were determined as a function of moisture content to optimize the design of equipment for post-harvest management. Several properties, including bulk density, dynamic repose angle, one thousand-kernel weight, specific gravity, length, width, thickness, and area of two wheat cultivars (Baekjjung: B and Jogyeong: J ), were studied in the moisture range from approximately 9% to 30% wet basis. As moisture increased, length increased linearly from 6.42 to 7.20 mm (B) and 8.71 to 9.15 mm (J), width increased from 2.90 to 3.49 mm (B) and 4.12 to 4.43 mm (J), thickness from 2.94 to 3.20 mm (B) and 3.29 to 3.63 mm (J), and area from 14.13 to $19.44mm^2$ (B) and 27.75 to $31.25mm^2$ (J). Additionally, the dynamic repose angle and one thousand-kernel weight increased linearly from $46.3^{\circ}$ to $54.0^{\circ}$ (B) and $46.3^{\circ}$ to $54.5^{\circ}$ (J) and from 32.26 to 41.51 g (B) and 45.30 to 63.07 g (J), respectively, as the moisture content increased. Based on the experimental measurements, only the bulk density and specific gravity decreased from 754.0 to $664.1kgm^{-3}$ (B) and 776.1 to $660.0kgm^{-3}$ (J) and from 1.2950 to 1.2265 (B) and 1.3379 to 1.2671 (J), respectively, as moisture content increased.