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The Characteristics of Black Carbon of Seoul (서울의 블랙카본 특성 연구)

  • Park, Jongsung;Song, Inho;Kim, Hyunwoong;Lim, Hyungbae;Park, Seungmyung;Shin, Suna;Shin, Hyejoung;Lee, Sangbo;Kim, Jeongho
    • Journal of Environmental Impact Assessment
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    • v.28 no.2
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    • pp.113-128
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    • 2019
  • The concentration and coating thickness of black carbon (BC) were measured along with fine dust in the fall of 2018, at the Seoul Metropolitan Area Intensive Monitoring Station (SIMS). In fall, the concentration of $PM_{10}$ and $PM_{2.5}$ was $23{\pm}12.6{\mu}g/m^3$ and $12{\pm}5.8{\mu}g/m^3$, respectively, lower than that in other seasons. The BC level, measured using an Aethalometer, was $0.73{\pm}0.43{\mu}g/m^3$, while the levels of elemental carbon (EC) and refractory-BC (rBC), measured by semi-continuous carbon analyzer (SOCEC) and single particle soot photometer (SP2), were $0.34{\pm}0.18{\mu}g/m^3$ and $0.32{\pm}0.18{\mu}g/m^3$, respectively. As such, the concentration level differed according to the measurement method, but its time-series distribution and diurnal variation showed the same trends. The BC concentration at SIMS was primarily affected by automobiles with higher levels of BC during morning and evening commuting times due to increased traffic congestion. rBC, measured by SP2, had a peak concentration and coating thickness of 84 nm and 43 nm, respectively. Notably, the coating thickness had an inverse relationship with particle size.

An essay on appraisal method over official administration records ill-balanced. -For development of appraisal process and method over chosun government-general office records- (불균형 잔존 행정기록의 평가방법 시론 - 조선총독부 공문서의 평가절차론 수립을 위하여 -)

  • Kim, Ik-Han
    • The Korean Journal of Archival Studies
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    • no.13
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    • pp.179-203
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    • 2006
  • This study develops the process and method of official administration documents which have remained ill-balanced like the official documents of the government-general of Chosun(the pro-Japanese colonial government (1910-1945)). At first, the existing Appraisal-theories are recomposed. The Appraisal-Theories of Schellenberg is focused valuation about value of records itself, but fuction-Appraisal theory is attached importance to operational activities which take the record into action. But given that the record is a re-presentation of operational activities, the both are the same on the philosophy aspect. Therefore, in the case that the process - method is properly designed, it can be possible to use a composite type between operational activities and records. Also, a method of the Curve has its strong points in the macro and balanced aspect while the Absolute has it's strength in the micro aspect, so that chances are that both alternate methodologies are applied to the study. Hereby, the existing Appraisal theories are concluded to be the mutually-complemented things that can be easily put together into various forms according to the characteristics of an object and its situation, in the terms of the specific Appraisal methodology. Especially, in the case of this article dealing with the imbalance remains official-documents, it is necessary to compromise more properly process with a indicated useful method than establishing a method and process by choosing the only one theory. In order to appraise the official-documents of the pro-Japanese colonial government (1910-1945), a macro appraisal of value has to be appraised about them by understanding a system, functions and using the historical-cultural evolution, after analysing Disposal Authority. From this, map the record so that organization function maps are constructed regarding the value rank of functions and detailed-functions. After this, establish the appraisal strategy considering the internal environment of archival agencies and based on micro appraisal to a great quantity of records remained and supplying other meaning to a small quantity of records remained for example, the oral resources production are accomplished. The study has not yet reached the following aspects ; a function analysis, historical decoding techniques, a curve valuation of the record, the official gazette of the government general of Chosun( the pro-Japanese government for 1910-1945), an analysis method of the other historical materials and it's process, presentation of appraisal output image. As the result, that's just simply a proposal and we should fill in the above-mentioned shortages of the study through development of all the up-coming studies.

Comparative Studies on Mechanism of Photocatalytic Degradation of Rhodamine B with Sulfide Catalysts under Visible Light Irradiation (가시광선하에서 황화물계 광촉매를 이용한 로다민 B의 광분해 반응기구에 대한 비교 연구)

  • Lee, Sung Hyun;Jeong, Young Jae;Lee, Jong Min;Kim, Dae Sung;Bae, Eun Ji;Hong, Seong Soo;Lee, Gun Dae
    • Clean Technology
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    • v.25 no.1
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    • pp.46-55
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    • 2019
  • CdS and CdZnS/ZnO materials were prepared using precipitation method and used as photocatalysts for the photocatalytic degradation of rhodamine B (RhB) under visible light irradiation. The prepared photocatalysts were also characterized by XRD and UV-vis DRS. The results indicated that the photocatalysts with intended crystalline structures were successfully obtained and both the CdS and CdZnS/ZnO can absorb visible light as well as UV. The photocatalytic activities were examined with the addition of scavenger for various active chemical species and the difference of reaction mechanisms over the catalysts were discussed. The $CH_3OH$, KI and p-benzoquinone were used as scavengers for ${\cdot}OH$ radical, photogenerated positive hole and ${\cdot}O_2{^-}$ radical, respectively. The CdS and CdZnS/ZnO showed different photocatalytic degradation mechanisms of RhB. It can be postulated that ${\cdot}O_2{^-}$ radical is the main active species for the reaction over CdS photocatalyst, while the photogenerated positive hole for CdZnS/ZnO photocatalyst. As a result, the predominant reaction pathways over CdS and CdZnS/ZnO photocatalysts were found to be the dealkylation of chromophore skeleton and the cleavage of the conjugated chromophore structure, respectively. The above results may be mainly ascribed to the difference of band edge potential of conduction and valence bands in CdS, CdZnS and ZnO semiconductors and the redox potentials for formation of active chemical species.

Expression and Purification of Three Lipases (LipAD1, LipAD2, and LipAD3) and a Lipase Chaperone (LipBD) from Acinetobacter schindleri DYL129 (Acinetobacter schindleri DYL129 유래의 3개 lipases와 chaperone의 발현과 정제)

  • Kim, Sun-Hee;Lee, Yong-Suk;Jeong, Hae-Rin;Pyeon, Hyo-Min;You, Ju-Soon;Choi, Yong-Lark
    • Journal of Life Science
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    • v.29 no.4
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    • pp.492-498
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    • 2019
  • Previously, three kinds of lipases, lipAD1, lipAD2, and lipAD3, and lipase chaperone, lipBD, of Acinetobacter schindleri DYL129 isolated from soil sample were reported. In this report, three lipase and lipase chaperone were cloned into the pET32a(+) or pGEX-6P-1 vectors for protein expression in Escherichia coli, and named as pETLAD1, pETLAD2, pETLAD3 and pETLBD or pGEXLAD1, pGEXLAD 2, pGEXLAD3 and pGEXLBD, respectively. Protein expression rate was higher in pET system than in pGEX system. Although LipAD1 and LipAD2 were produced as inclusion bodies, their expression levels were high. So LipAD1 and LipAD2 could be solubilized in 8 M urea buffer and purified. LipAD3 and LipBD were overexpressed in soluble form and purified. Those proteins were purified by His-tag affinity chromatography connected in AKTA prime system. The activities of the purified lipases were demonstrated with 1% tributyrin agar plate. After purification, molecular mass was determined with sodium dodecyl sulfate-polyacrylamide gel electrophoresis. LipAD1 showed high activity toward ${\rho}$-nitrophenyl acetate and ${\rho}$-nitrophenyl butyrate, LipAD2 showed high activity toward ${\rho}$-nitrophenyl acetate and ${\rho}$-nitrophenyl myristate, and LipAD3 showed high activity toward ${\rho}$-nitrophenyl acetate, ${\rho}$-nitrophenyl butyrate, and ${\rho}$-nitrophenyl miristate, respectively. Three lipases, LipAD1, LipAD2, and LipAD3, showed optimal reaction at $50^{\circ}C$ using ${\rho}$-nitrophenyl butyrate, as substrate.

Estimation of Baseflow based on Master Recession Curves (MRCs) Considering Seasonality and Flow Condition (계절·유황특성을 고려한 주지하수감수곡선을 활용한 기저유출분리 평가)

  • Yang, Dongseok;Lee, Seoro;Lee, Gwanjae;Kim, Jonggun;Lim, Kyoung Jae;Kim, Ki-Sung
    • Journal of Wetlands Research
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    • v.21 no.1
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    • pp.34-42
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    • 2019
  • Baseflow which is one of the unmeasurable components of streamflow and slowly flows through underground is important for water resource management. Despite various separation methods from researches preceded, it is difficult to find a significant separation method for baseflow separation. This study applied the MRC method and developed the improved approach to separate baseflow from total streamflow hydrograph. Previous researchers utilized the whole streamflow data of study period at once to derive synthetic MRCs causing unreliable results. This study has been proceeded with total nine areas with gauging stations. Each three areas are selected from 3 domestic major watersheds. Tool for drawing MRC had been used to draw MRCs of each area. First, synthetic MRC for whole period and two other MRCs were drawn following two different criteria. Two criteria were set by different conditions, one is flow condition and the other is seasonality. The whole streamflow was classified according to seasonality and flow conditions, and MRCs had been drawn with a specialized program. The MRCs for flow conditions had low R2 and similar trend to recession segments. On the other hand, the seasonal MRCs were eligible for the baseflow separation that properly reflects the seasonal variability of baseflow. Comparing two methods of assuming MRC for baseflow separation, seasonal MRC was more effective for relieving overestimating tendency of synthetic MRC. Flow condition MRCs had a large distribution of the flow and this means accurate MRC could not be found. Baseflow separation using seasonal MRC is showing more reliability than the other one, however if certain technique added up to the flow condition MRC method to stabilize distribution of the streamflow, the flow conditions method could secure reliability as much as seasonal MRC method.

FTA Negotiation Strategy and Politics in the Viewpoint of the Three-Dimensional Game Theory: Korea-EU FTA and EU-Japan EPA in Comparison (삼차원게임이론의 관점에서 바라 본 유럽연합의 FTA 협상 전략 및 정치: 한-EU FTA와 EU-일본 EPA의 비교를 중심으로)

  • Kim, Hyun-Jung
    • Journal of International Area Studies (JIAS)
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    • v.22 no.2
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    • pp.81-110
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    • 2018
  • In this paper, we examined the regional economic integration, the trade negotiation strategy and bargaining power of the European Union through the logical structure of the three - dimensional game theory. In the three - dimensional game theory, the negotiator emphasized that the negotiation strategy of the triple side existed while simultaneously operating the game standing on the boundary of each side game, constrained from each direction or occasionally using the constraint as an opportunity. The study of three-dimensional game theory is aimed at organizing the process of coordinating opinions and meditating interests at the international level, regional level and member level by the regional union as a subject of negotiation. This study would compare and analyze the recently concluded EU-Japan EPA (Economic Partnership Agreement) negotiation process with the case of the EU FTA, and summarize the logic of the three-dimensional game theory applicable to the FTA of the regional economic partnership. Furthermore, the study would illustrate the strategies of the regional economic cooperatives to respond to negotiations. The area of trade policy at the EU level has already been completed by the exclusive power of the Union on areas where it is difficult to politicize with technical features. Moreover, the fact that the policy process at the Union level has not been revealed as a political issue, and that the public opinion process is a double-step approach. In conclusion, the EU's trade policy process constitutes a complicated and sophisticated process with the allocation of authority by various central organizations. The mechanism of negotiation is paradoxically simplified because of the common policy decision process and the structural characteristics of the trade zone, and the bargaining power at the community level is enhanced. As a result, the European Commission would function as a very strong negotiator in bilateral trade negotiations at the international level.

The Association Between Accounting Conservatism and Corporate Investment Expenditure in Korean Listed Firms During the Global Financial Crisis (글로벌 금융위기가 한국 기업의 투자지출에 미치는 영향에 대한 실증적 분석: 회계보수주의를 중심으로)

  • Kim, Byoung Ho
    • International Area Studies Review
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    • v.22 no.3
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    • pp.121-148
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    • 2018
  • This paper examines the role of accounting conservatism on investment expenditure for non-financial Korean listed firms around the 2007-2008 global financial crisis using a differences-in-differences design. Specifically, this paper examines the association between an ex ante classification of firms by their level of accounting conservatism prior to the credit crisis and the ex post magnitude of the decline in investment. Consistent with prior literature, this study found that firms experienced a decline in their investment when hit by the financial crisis (Campello et al. 2010). And also this study found that firms with more conservative financial reporting experienced a smaller decline in investment activity following the financial crisis than did firms with less conservative financial reporting. Together, the results suggest that negative shocks to the supply of external finance hampers firm-level investment and that conservative financial reporting can lessen the sensitivity of firms' investment to such negative shocks. Next, this study shows that the magnitude of our findings is greater for firms more likely to suffer from underinvestment (as opposed to overinvestment). Firms that are financially constrained or have greater demand for external finance are more likely to experience underinvestment. Consistent with the predictions, this study finds stronger benefits of conservatism for firms that face relatively greater costs in raising external capital (i.e., financially constrained firms) or that have a relatively greater need to do so (i.e., firms that lack internal financial resources). This study also finds that the role for conservatism is greater in firms with a higher level of information asymmetry, consistent with the notion that conservatism mitigates financing frictions arising from information problems.

A study of prostate symptom, sleep quality and quality of life in the community-dwelling korean elderly (남성 노인의 전립선 증상, 수면의 질, 삶의 질에 관한 연구)

  • Shin, Kyung-Rim;Kang, Younhee;Shin, Mee-Kyung
    • 한국노년학
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    • v.28 no.4
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    • pp.1041-1054
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    • 2008
  • This study aimed to identify the severity and types of prostate symptom, to identify the relationship of prostate symptom, sleep quality and quality of life of the elderly in korea, so to provide basic data for developing nursing interventions for the elderly's prostate symptom management. This study used a descriptive correlational research design. The subjects of this study were 100 elderly men over 65yr in an urban city. Data were collected through personal interviews using questionnaires from September 2006 to March 2007. The IPPS, PSQI and SF-36-K were administered. The collected data were analyzed by descriptive statistics and Pearson's correlation. The major findings of this study were as follows: 1) 44% of the participants have moderate to severe Prostate symptom(IPSS>7). 2) Prostate symptom has positive relationship with sleep quality(r=.272, p=.006) and negative relationship with health related quality of life(r=-.197, p=.049). The results of this study indicate that prostate symptom is related to sleep quality and quality of life. So it is necessary to give information to the elderly about the effective coping method of prostate symptom and about the life style which have positive effect to prostate symptom.

A Systematic Review of Community Elder Abuse Studies in South Korea (한국 지역사회 거주 노인학대 연구의 체계적 고찰)

  • Kim, Dong Ha;Kang, Serin;Lee, Yoon Kyoung;Cha, Ye Won;Yoo, Seunghyun;Kim, Hongsoo
    • 한국노년학
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    • v.36 no.4
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    • pp.1003-1024
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    • 2016
  • The human rights of older people have gotten more attention recently in South Korea, a country that is in transition to a super-aged society. This study aimed to systematically review studies on elder abuse and related factors among community-dwelling older adults in South Korea over twenty years (1994-2016). We searched major databases (Riss, DBpia, KISS, KMbase, and PubMed) and identified published studies relevant to the topic. Based on inclusion and exclusion criteria related to study quality, a total of 31 studies were selected for this review. We examined types, measurements, and risk factors of elder abuse as well as study designs in the selected studies, guided by Johannesen's theoretical framework on elder abuse. All of the reviewed studies on elder abuse in Korea were cross-sectional studies, most of which focused on older people living in urban areas, using a non-random sampling method. All of the studies focused on certain types of elder abuse only. Some adopted elder-abuse instruments that were not validated, and others used self-developed instruments without psychometric tests. As for the risk factors of elder abuse in South Korea, the physical and mental health of the victims and aggressors impacted the risk of elder abuse, but general sociodemographic factors such as age, sex, and education were less likely to be related to the risk. In addition, decreasing caregiver burden and building elder-friendly communities are important for the prevention of elder abuse. Needed are further empirical studies on elder abuse with a theoretical framework that gives consideration to the unique sociocultural contexts of Korea. It is also recommended to develop instruments to measure elder abuse reflecting the sociocultural contexts of Korea, and to examine the multi-dimensional risk factors of elder abuse.

A Study on the Application Effect of Central-Grid PV System at a Streetlamp using RETScreen - A Case Study of Gwangjin-gu - (RETScreen을 이용한 가로등의 계통연계형 태양광시스템 적용 효과 분석 - 서울시 광진구를 중심으로 -)

  • Kang, Seongmin;Choi, Bong-Seok;Kim, Seungjin;Mun, Hyo-dong;Lee, Jeongwoo;Park, Nyun-Bae;Jeon, Eui-Chan
    • Journal of Climate Change Research
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    • v.5 no.1
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    • pp.1-12
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    • 2014
  • With continued economic growth, Korea has seen an increase in the nighttime activities of its citizens as hours of activity have extended into night. There is an increasing trend in energy consumption related to citizens' nighttime activities. In order to analyze ideas for an efficient replacement of the power consumption of streetlights and for profit generation by applying grid-type solar systems, this study used an RETScreen model. Through energy analysis and cost analysis, the application benefit and viability of grid-type solar street light systems were analyzed. With analysis result of a total weekly power generation of 114 kWh via a grid-connected solar streetlight system, it was shown that the net present value of a grid-connected solar street light system is 155,362 KRW, which would mean a payback period of about 5.2 years, and as such, it was shown that profit could be generated after about 6 years. In addition, if the grid-connected solar power generation system proposed by this study is to be applied, it was shown that 401,935 KRW in profit could be generated after the 20-year useful life set for the solar system. In addition, the sensitivity analysis was performed taking into account the price fluctuations of SMP, maintenance. As a result, a payback period has increased by 1~2 years, and there were no significant differences. Because the most important factor that affect the economic analysis is the cost of supply certification of renewable energy, a stable sales and acquisition of this certification are very important. the Seoul-type Feed in Tariff(FIT) connected to other institutions will enable steady sales by confirming to purchase the certification for 12 years. Therefore, if those issues mentioned above are properly reflected, Central-grid PV system project will be able to perform well in the face of unfavorable condition of solar PV installation.