• Title/Summary/Keyword: Long Range

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Relationship between Macrofungi Fruiting and Environmental Factors in Songnisan National Park (속리산 국립공원의 버섯발생과 환경요인과의 관계)

  • Park, Yong-Woo;Koo, Chang-Duck;Lee, Hwa-Yong;Ryu, Sung-Ryul;Kim, Tae-Heon;Cho, Young-Gull
    • Korean Journal of Environment and Ecology
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    • v.24 no.6
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    • pp.657-679
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    • 2010
  • Mushroom fruiting was investigated in pine and oak dominated forest stands in Songni National Park located in central Korea for six years from 2003 to 2008, in order to understand the relationship between mushroom diversity and the environmental factors, precipitation, temperature, soil moisture and vegetation. The most frequent fruiting families were those of ectomycorrhizal mushrooms, Tricholomataceae, Amanitaceae, Russulaceae, Cortinariaceae, and Boletaceae. The frequency of mushroom fruiting varied from 94 to 167 species per year, with July and August having the highest(13~90 species). Mushroom fruiting was positively correlated to precipitation(r=0.897), using Palmer Drought Severity Index for the long term period and Standard Precipitation Index for short term period. Soil moisture content also affected mushroom fruiting, with Lactarius chrysorrheus and Russula virescens fruiting only at soil moisture content higher than 20%. Positive correlation between mushroom fruiting and temperature was also noted(r=0.77), with optimum rates at $21{\sim}25^{\circ}C$. Tricholoma flayayirens, Amanita gymnopus, Lactarius piperatus, Inocybe asteropora and Xerocomus chrysenteron were able to fruit at temperatures higher than $25^{\circ}C$. However, Laccaria amethystea, Amanita virosa and Russula mariae fruited at relatively wide temperature range. The influence of vegetation on mushroom fruiting was likewise noted, with 38 species, including Suillus bovinus and Boletopsis leucomelas being specific to pine dominated stands, while 42 species, including Polyporus arcularius and Hericium erinaceum were specific to oak dominated stands. On the other hand, around 50 species, including Laccaria laccata and Lycoperdon parlatum, were able to fruit in both types of vegetation. In conclusion, mushroom fruiting greatly varies with changes in precipitation, soil moisture, temperature and vegetation.

The Achievements and limitations of the U. S. Welfare Reform (미국 복지개혁의 성과와 한계)

  • Kim, Hwan-Joon
    • Korean Journal of Social Welfare
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    • v.53
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    • pp.129-153
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    • 2003
  • This study examines the socio-economic impacts of recent welfare reform in the United States. Based on the neo-conservative critique to the traditional public assistance system for low-income families, the 1996 welfare reform has given greater emphases on reducing welfare dependency and increasing work effort and self-sufficiency among welfare recipients. In particular, the welfare reform legislation instituted 60-month lifetime limits on cash assistance, expanded mandatory work requirements, and placed financial penalties for noncompliance. With the well-timed economic boom in the second half of the 1990s, the welfare reform seems to achieve considerable progress; welfare caseload has declined sharply to reach less than 50% of its 1994 peak, single mothers' labor force participation has increased substantially, and child poverty has decreased. In spite of these good signals, the welfare reform also has several potential problems. Many welfare leavers participate in the labor market, but not all (or most) of them. The economic well being of working welfare leavers did not increased significantly, because earnings increase was canceled out by parallel decrease in welfare benefits. Furthermore, most of working welfare leavers are employed in jobs with poor employment stability and low wages, making them highly vulnerable to frequent layoff, long-time joblessness, persistent poverty, and welfare recidivism. Another serious problem of the welfare reform is that a substantial number of welfare recipients are faced with extreme difficulties in finding jobs, because they have severe barriers to employment. The new welfare system with 5-year time limit can severely threaten the livelihoods of these people. The welfare reform presupposes that welfare recipients can achieve self-reliance by increasing their labor market activities. However, empirical evidences suggest that many people are unable to respond to the new, work-oriented welfare strategy. It may be a very difficult task to achieve both objectives of the welfare reform((1) providing adequate income security for low-income families and (2) promoting self-sufficiency) at the same time, because sometimes they are conflicting each other. With this in mind, a possible solution can be to distinguish welfare recipients into "(Very)-Hard-to-Employ" group and "(Relatively)-Ready-to-Work" group, based on elaborate examinations of a wide range of personal conditions. For the former group, the primary objective of welfare policies should be the first one(providing income security). For the "Ready-to-Work" group, follow-up services to promote job retention and advancement, as well as skill-training and job-search services, are very important. The U. S. experiences of the welfare reform provide some useful implications for newly developing Korean public assistance policies for the able-bodied low-income population.

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A Study on the Smog Reduction Strategies in China (중국의 스모그 저감정책에 대한 고찰)

  • Jeon, So Hyeon;Kim, Yong Pyo
    • Particle and aerosol research
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    • v.11 no.3
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    • pp.63-75
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    • 2015
  • Atmospheric environment in Korea is influenced by outside, especially China. The concentrations of air pollutants in China have showed decreasing trends since 2000. However, these concentration levels in China are still higher than other developed countries. The Chinese Government has tried several measures to control the air pollution. In this study, the details of the amendments and smog reduction strategies in China, especially for Beijing are reviewed and the strategies for Korean side to promote cooperation in Northeast Asia are suggested and discussed. The Chinese State Council amended the Environmental Protection Provisions and Clean Air Act and announced The Action Plan for Air Pollution Control (2013-2017), focusing on three key regions, Beijing-Tianjin-Hebei area (Jing-Jin-Ji), Yangtze River Delta (YRD) and Pearl River Delta (PRD). These policy actions and plan are mainly for the reducing coal usage and emissions from vehicles. It is suggested that, Korea should actively promote multi-national cooperation in the region to take an initiative role in environmental areas.

Changes of Growth and Flowering Characteristics in Rapeseed Cultivars with Different Sowing Date (파종시기에 따른 유채(Brassica napus L.) 품종별 생육 및 개화특성)

  • Lee, Tae Sung;Lee, Yong Hwa;Kim, Kwang Soo;Lee, Hoo Kwan;Jang, Young Seok;Choi, In Hu;Kim, Kwan Su
    • Korean Journal of Plant Resources
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    • v.27 no.1
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    • pp.80-88
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    • 2014
  • This study was carried out to understand the effect of sowing date on growth characteristics, flower duration of a total of 6 domestic rapeseed cultivars, "Sunmang", "Tammiyuchae", "Tamlayuchae", "Naehanyuchae", "Yongsanyuchae" and "Hallayuchae" with different sowing dates (25 Sept., 5 Oct., 15 Oct., 25 Oct., 5 Nov.) in Muan, Jeollanamdo, Republic of Korea. The results obtained were summarized as the follows: The number of seedling stand after overwintering was decreased in all 6 cultivars. It changed little until 5 Oct., and then showed continuously largely decrease as the sowing date being delayed. As the sowing date was being delayed, plant height was decreased while Silique length and thousand seed weight were increased. Seed yield in all 6 cultivars decreased almost linearly with late sowing date. In correlation analysis between the delaying sowing date and growth characteristics, it was inversely correlated with plant height ($r=-0.769^{**}$), No. of branches/plant ($r=-0.760^{**}$), No. of siliqua/panicle ($r=-0.631^{**}$) and seed yield ($r=-0.946^{**}$), while showed a positive correlation with silique length (r=0.635), seed diameter ($r=0.629^{**}$) and thousand grain weight ($r=0.422^*$). No. of seeds/silique and seed set percentage were not significantly correlated with the delaying sowing date. The flower duration was long in order of Sunmang, Tammiyuchae, Yongsanyuchae, Naehanyuchae, Hallayuchae and Tamlayuchae. Varietal variation of flowering date was larger with early sowing date than with delaying sowing date. The range of flower duration across all cultivars was from 1 day of Tamlayuchae to 14 days of Sunmang according to the sowing date, and the end flowering date was able to be extended from 2 to 9 days, compared to normal date of end flowering.

Influence on Intra-limb Coordination in Individuals Wearing a Knee Extension Constraint Brace during Walking (무릎 신전 제한형 보조기 착용이 보행 시 하지 내 협응에 미치는 영향)

  • Chang, Yoonhee;Jeong, Bora;Kang, Sungjae;Ryu, Jeicheong;Kim, Gyu Seok;Mun, Museong;Ko, Chang-Yong
    • Journal of rehabilitation welfare engineering & assistive technology
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    • v.10 no.3
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    • pp.207-214
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    • 2016
  • The aim of this study was to evaluate Influence on intra-limb coordination in individuals wearing knee brace during walking. Seven healthy male adults ($32.3{\pm}2.7$ years old, $175.2{\pm}3.8cm$, $76.2{\pm}8.7kg$) participated. They wore knee brace or didn't wear any knee brace and were asked to walk along a 10 m long walkway. Spatiotemporal parameters, angles of the lower limbs, and intra-limb continuous relative phase (CRP) were measured and calculated. No differences of spatiotemporal parameters were shown (all p > 0.05). There were no changes in the angle and its range of motion (ROM) in the hip for the subjects as wearing knee brace, while ROM ($65.5{\pm}3.7^{\circ}$ vs. $60.5{\pm}3.5^{\circ}$, p < 0.05) of the angle and maximum flexion angles (stance: $31.9{\pm}4.6$ vs. $25.6{\pm}5.5$, swing: $76.7{\pm}3.1$ vs. $68.9{\pm}3.4$, all p < 0.05) in the knee significantly decreased. No changes in ROM of angle in the ankle were shown, whereas maximum dorsiflexion decreased ($22.4{\pm}2.6$ vs. $19.2{\pm}2.1$, p < 0.05) and maximum plantarflexion increased ($9.5{\pm}3.0$ vs. $15.7{\pm}2.2$, p<0.05). There were no changes in most of CRP between joints. CRP between the hip and knee joints decreased ($93.0{\pm}7.8$ vs, $84.7{\pm}4.9$, p < 0.05). Most of CRP standard deviation increased (between the hip and ankle joint during swing: $25.1{\pm}6.7$ vs. $32.4{\pm}1.9$, between the knee and ankle joint during stance: $46.0{\pm}12.9$ vs. $80.1{\pm}31.1$, between the knee and ankle joint during swing: $34.5{\pm}4.1$ vs. $37.6{\pm}3.1$, all p < 0.05). These results indicated that wearing knee brace affected joint angle and intra-limb coordination, but less affected gait features.

An Analysis of Papers used in Historical Manuscrips (조선시대 고문서(古文書)에 사용된 종이 분석)

  • Son, Ke-Young
    • Journal of Korean Society of Archives and Records Management
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    • v.5 no.1
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    • pp.79-105
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    • 2005
  • This study is that the name from Tagjijunjeol is compared with the actual papers used in historical documents. I have selected the families having had influencing power in Gyungi-Do(京畿道), Gyungsang-Do(慶尙道), Jeonra-Do(全羅道), Chungcheung-Do(忠淸道), and analyzed 1504 articles of historical documents owned by those families. I checked up each papers used in historical documents in it's shape of screens, density, raw material. I cannot find the feature of it's region, but prominent feature according to the types and period of historical documents. At first, I have surveyed the impressions of screen marks in papers. The number of strips can be divided into two cases, around 10 and around 17. The case around 17 is similar to the number seen in the book paper of the early Joseon Dynasty, but the case around 10 is rare. Dard Hunter said in his book, published in 1933, that screens were made of Korean grass(Miscanthus sp.) at that time in Korea. I guess the impressions of screen marks of the case around 10 was made of Korean grass, Miscanthus sp.. The case around 10 and the case around 17 were not different in period, but the contemporary appearance. However, if we look into the change of strips' number, we can learn that it becomes more dense as time goes by. The intervals of hair stitch, contrary to book paper, have appeared irregularly and a short hair stitch was frequently found between long hair stitches. This was the result of fastening extra stitch to increase the firmness of strips, as the part of screens which was frequently touched by hands would wear out easily. Then, have look into the density. Each kinds of historical documents had a wide range of density. But the average have had relationship with the kinds of paper written in Tagjijunjeol. The historical documents having the same item of paper have kept similar densities. From the density variation of Gosingyoji(告身敎旨), the letter of appointment the official rank over 5 by king, based on time periods, we can see a great disparity between before and after Imjin-waeran war. Before Imjin-waeran war paper's quality was high, right after Imjin-waeran war went abruptly down, and went gradually up just from 1650's, but since 1700's quality has not risen more, kept the value. On the contrary, the density of Gyocheop(敎牒), the letter of appointment the official rank under 5 by the Ministry of Personnel and the Ministry of Military, have not had a great disparity according to time periods, but had a lower density than Gosingyoji. Joseon Dynasty has strictly divided Gosingyoji appointing the official rank over 5 from Gyocheop appointing the official rank under 5, it seems to distinguish the appointment by king from the appointment by Ijo(吏曹), the Ministry of Personnel and Byeongjo(兵曹), the Ministry of Military.

Underpricing of Initial Offerings and the Efficiency of Investments (신주(新株)의 저가상장현상(低價上場現象)과 투자(投資)의 효율성(效率成)에 대한 연구(硏究))

  • Nam, Il-chong
    • KDI Journal of Economic Policy
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    • v.12 no.2
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    • pp.95-120
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    • 1990
  • The underpricing of new shares of a firm that are offered to the public for the first time (initial offerings) is well known and has puzzled financial economists for a long time since it seems at odds with the optimal behavior of the owners of issuing firms. Past attempts by financial economists to explain this phenomenon have not been successful in the sense that the explanations given by them are either inconsistent with the equilibrium theory or implausible. Approaches by such authors as Welch or Allen and Faulhaber are no exceptions. In this paper, we develop a signalling model of capital investment to explain the underpricing phenomenon and also analyze the efficiency of investment. The model focuses on the information asymmetry between the owners of issuing firms and general investors. We consider a firm that has been owned and operated by a single owner and that has a profitable project but has no capital to develop it. The profit from the project depends on the capital invested in the project as well as a profitability parameter. The model also assumes that the financial market is represented by a single investor who maximizes the expected wealth. The owner has superior information as to the value of the firm to investors in the sense that it knows the true value of the parameter while investors have only a probability distribution about the parameter. The owner offers the representative investor a fraction of the ownership of the firm in return for a certain amount of investment in the firm. This offer condition is equivalent to the usual offer condition consisting of the number of issues to sell and the unit price of a share. Thus, the model is a signalling game. Using Kreps' criterion as the solution concept, we obtained an essentially unique separating equilibrium offer condition. Analysis of this separating equilibrium shows that the owner of the firm with high profitability chooses an offer condition that raises an amount of capital that is short of the amount that maximizes the potential profit from the project. It also reveals that the fraction of the ownership of the firm that the representative investor receives from the owner of the highly profitable firm in return for its investment has a value that exceeds the investment. In other words, the initial offering in the model is underpriced when the profitability of the firm is high. The source of underpricing and underinvestment is the signalling activity by the owner of the highly profitable firm who attempts to convince investors that his firm has a highly profitable project by choosing an offer condition that cannot be imitated by the owner of a firm with low profitability. Thus, we obtained two main results. First, underpricing is a result of a signalling activity by the owner of a firm with high profitability when there exists information asymmetry between the owner of the issuing firm and investors. Second, such information asymmetry also leads to underinvestment in a highly profitable project. Those results clearly show the underpricing entails underinvestment and that information asymmetry leads to a social cost as well as a private cost. The above results are quite general in the sense that they are based upon a neoclassical profit function and full rationality of economic agents. We believe that the results of this paper can be used as a basis for further research on the capital investment process. For instance, one can view the results of this paper as a subgame equilibrium in a larger game in which a firm chooses among diverse ways to raise capital. In addition, the method used in this paper can be used in analyzing a wide range of problems arising from information asymmetry that the Korean financial market faces.

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A Landscape of Joseon Dynasty in Late 19th Century through Experience Record of Modern Westerners - Focused on Landscape Vocabulary and Content Analysis - (근대기 서양인들의 조선견문기를 통해 본 19세기 말 조선의 경관 - 경관 관련 어휘와 내용 분석을 중심으로 -)

  • Kim, Dong-Hyun;Shin, Hyun-Sil
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.36 no.1
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    • pp.20-33
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    • 2018
  • This study aims to illuminated landscape of Joseon Dynasty in the end of 19th century when Joseon dynasty began to modernize through the perspective of Westerners. Historical meaning to Western people's landscape records has been preceded. And landscape typology and their perception were analyzed. The results were as follows. First, the Westerners who visited Joseon dynasty at that time were involved in the historical and political situation of the Joseon Dynasty or understood their culture through traveling for so long. And record of Westerners is a significant data to analyze scenery at that time because common contents appear in various books. Second, the landscape of Joseon dynasty that appears in Western records was mainly recorded in small towns and villages, natural environments, scenic sites, historic sites, modern facilities, and cultivated areas. Small towns and villages are mainly mentioned with shabby alleys and dense houses. And natural landscape were identified to mountain landscapes and diverse geomorphological landscape that surrounding vegetation along the coast and rivers. The palaces, fortress and temples were recorded as main objects of scenic sites and historic site. And western-style buildings such as foreign legations and settlements, churches and schools were mentioned in the modernized facilities. A cultivated land was confirmed to be underdeveloped and neglected, but as range of view became wider, it was seen to a peaceful and prosperous rural landscape. Third, Westerners' landscape perception of Joseon dynasty at that time can be deduced from positive or negative perceptions. The residential environment was perceived as negative because it was unsanitary and backward. On the contrary, outstanding natural landscapes, scenic sites and historic sites, and upper class gardens were perceived as positive. For modernized landscapes, positive and negative perceptions were similarly mentioned. Positive perceptions were formed in improvement of civilized landscape, and appeared negative perception because damaged traditional landscapes and heterogeneity.

Spectral Response of $TiO_{2}$/Se : Te Heterojunction for Color Sensor (컬러센서를 위한 $TiO_{2}$/Se : Te 이종접합의 스펙트럼 응답)

  • Woo, Jung-Ok;Park, Wug-Dong;Kim, Ki-Wan;Lee, Wu-Il
    • Journal of Sensor Science and Technology
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    • v.2 no.1
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    • pp.101-108
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    • 1993
  • $TiO_{2}$/Se : Te heterojunction for color sensor has been fabricated by RF reactive sputtering and thermal evaporation methods onto glass substrate. The optimum deposition condition of $TiO_{2}$ films was such that RF power was 120 W, substrate temperature was $100^{\circ}C$, oxygen concentration was 50%, working pressure was 50 mTorr for the $TiO_{2}$ film thickness of $1000{\AA}$. In this case, the optical transmittance of $TiO_{2}$ film at 550 nm-wavelength was 85%, resistivity was $2{\times}10^9{\Omega}{\cdot}cm$, refractive index was 2.3, and optical bandgap was 3.58 eV. The composition ratio of 0 to Ti by AES analysis was 1.7. When $TiO_{2}$ films were annealed at $400^{\circ}C$ for 30 min. in $O_{2}$ ambient, the optical transmittance of $TiO_{2}$ films at the wavelength range of $300{\sim}580$ nm was improved from 0 to 25%. When Se : Te films were annealed at $190^{\circ}C$ for 1 min., photosensitivity under illumination of 1000 lux was 0.75. The optical bandgap of Se : Te films was 1.7 eV. The structures of Se : Te films were the hexagonal with (100) and (110) orientation. The spectral response of a-Se was improved by the addition of Te, especially in the long wavelength region. The $TiO_{2}$/Se : Te heterojunction showed wide spectral response, and more improved one than that of a-Si film in the blue light region.

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Analyzing the Influence of Biomass and Vegetation Type to Soil Organic Carbon - Study on Seoseoul Lake Park and Yangjae Citizen's Forest - (바이오매스량과 식생구조가 토양 탄소함유량에 미치는 영향 분석 - 서서울호수공원과 양재 시민의 숲을 대상으로 -)

  • Tanaka, Riwako;Kim, Yoon-Jung;Ryoo, Hee-Kyung;Lee, Dong-Kun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.17 no.1
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    • pp.123-134
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    • 2014
  • Identification of methods to optimize the growth of a plant community, including the capacity of the soil to further sequester carbon, is important in urban design and planning. In this study, to construct and manage an urban park to mitigate carbon emissions, soil organic carbon of varying biomass, different park construction times, and a range of vegetation types were analyzed by measuring aboveground and belowground carbon in Seoseoul Lake Park and Yangjae Citizen's Forest. The urban parks were constructed during different periods; Seoseoul Lake Park was constructed in 2009, whereas Yangjae Citizen's Forest was constructed in 1986. To identify the differences in soil organic carbon in various plant communities and soil types, above and belowground carbon were measured based on biomass, as well as the physical and chemical features of the soil. Allometric equations were used to measure biomass. Soil total organic carbon (TOC) and chemical properties such as pH, cation exchange capacity (CEC), total nitrogen (TN), and soil microbes were analyzed. The analysis results show that the biomass of the Yangjae Citizen's Forest was higher than that of the Seoseoul Lake Park, indicating that older park has higher biomass. On the other hand, TOC was lower in the Yangjae Citizen's Forest than in the Seoseoul Lake Park; air pollution and acid rain probably changed the acidity of the soil in the Yangjae Citizen's Forest. Furthermore, TOC was higher in mono-layered plantation area compared to that in multi-layered plantation area. Improving the soil texture would, in the long term, result in better vegetation growth. To improve the soil texture of an urban park, park management, including pH control by using lime fertilization, soil compaction control, and leaving litter for soil nutrition is necessary.