• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.341-348
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• 2013

Maintenance of adequate soil tension or content during the period of crop growth is necessary to support optimum plant growth and yields. A better understanding of soil tension and content for precision irrigation would allow optimal soil water condition to crops and minimize the adverse effects of water stress on crop growth and development. This research reports on a comparison of soil water tension and content variations in differently textured soils over time under drip irrigation using two different water management methods, i.e. pulse time and required water irrigation methods. The pulse time-based irrigation was performed by turning the solenoid valve on and off for preset times to allow the wetting front to disperse in root zone before additional water was applied. The required water estimation method was a new water control logic designed by Rural Development Administration that applies the amount of water required based on a conversion of the measured water tension into water content. The use of the pulse time irrigation method under drip irrigation at a high tension of -20 kPa and high temperatures over $30^{\circ}C$ was not successful at maintaining moisture tensions within an appropriate range of 5 kPa because the preset irrigation times used for water control could not compensate for the change in evapotranspiration during day and night. The response time and pattern of water contents for all of the tested soils measured with capacitance-based sensor probes were faster and more direct than those of water tensions measured with porous and ceramic cup-based tensiometers when water was applied, indicating water content would be a better control variable for automatic irrigation. The required water estimation-based irrigation method provided relatively stable control of moisture tension, even though somewhat lower tension values were obtained as compared to the target tension of -20 kPa, indicating that growers could expect to be effective in controlling low tensions ranging from -10 to -20 kPa with the required water estimation system.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.373-383
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• 2012

Soybean, C.V. Daewonkong, was planted on 25 May and 25 June in 2011, and four temperature gradient, control (ambient temperature in field plot), control + $3^{\circ}C$, control + $4^{\circ}C$, and control + $5^{\circ}C$, were artificially created by controlling the green house system. The obtained results indicated that vegetative growth of soybean plant was beneficially facilitated by planting on May (PM) than planting on June (PJ). The 100-seed weight was significantly higher in PM, and positively affected by increasing temperature, whereas the weight was reduced in control + $5^{\circ}C$ plot. Isoflavone content and fatty acid composition were analyzed to determine the effects of plating date and growth temperature. Isoflavone content was higher in PJ plot ($1479.8{\mu}g/g$) than in PM plot ($1201.8{\mu}g/g$), however, the influence of growth temperature varied with planting date. The composition of oleic acid was positively affected by increasing temperature, whereas the proportions of linoleic and linolenic acid were reduced. The numbers of node was considered as a major variable in the regression equations estimated using forward stepwise regression analysis for isoflavone content and unsaturated fatty acid under different environmental conditions.

• Journal of Yeungnam Medical Science
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• v.10 no.1
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• pp.190-196
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• 1993

The prognosis of chronic hepatitis C is very variable. In some, the disease is progressive and cirrhosis can develop from chronic hepatitis C. Hepatitis C virus(HCV) may act as a trigger towards hepatocellular carcinoma in patients with cirrhosis. Interferon has been used for the treatment of chronic hepatitis C in abroad, 16 patients with chronic C liver disease were treated with ${\alpha}$-interferon (alfa-2b; "Intron A" Schering Corp. Kenilworth. NJ). All patients were given ${\alpha}$-interferon in subcutaneous doses of 3 million units three times weekly for 1 to 9 months. During therapy, CBC and ALT levels were checked weakly to monthly. After therapy, patients were followed for 1 to 8 months. Among 16 patients treated with ${\alpha}$-interferon, progressive decrease of ALT levels was observed in 14(87.5%). In 11 patients(68.8%), ALT levels fell into the normal range during therapy, and in 9 of 11, within one month after therapy, 6 months after the completion of therapy in 4 of 9 patients(44.4%) whose ALT levels were in the normal range, ${\alpha}$-interferon seems to have effect in controlling disease activity in patients with chronic hepatitis C. But the changes in the usage of ${\alpha}$-interferon, dose and duration, long term follow up and more convenient and simple tests for HCV detection are recommended for the better effect and the exact evaluation on the effect of ${\alpha}$-interferon therapy in patients with chronic hepatitis C.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.8-9
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• 2017

Soybean yield has been low and unstable in Japan and other areas in East Asia, despite long history of cultivation. This is contrasting with consistent increase of yield in North and South America. This presentation tries to describe perspective of breaking stagnation of soybean yield in East Asia, considering the factors of the different yields between regions. Large amount of rainfall with occasional dry-spell in the summer is a nature of monsoon climate and as frequently stated excess water is the factor of low and unstable soybean yield. For example, there exists a great deal of field-to-field variation in yield of 'Tanbaguro' soybean, which is reputed for high market value and thus cultivated intensively and this results in low average yield. According to our field survey, a major portion of yield variation occurs in early growth period. Soybean production on drained paddy fields is also vulnerable to drought stress after flowering. An analysis at the above study site demonstrated a substantial field-to-field variation of canopy transpiration activity in the mid-summer, but the variation of pod-set was not as large as that of early growth. As frequently mentioned by the contest winners of good practice farming, avoidance of excess water problem in the early growth period is of greatest importance. A series of technological development took place in Japan in crop management for stable crop establishment and growth, that includes seed-bed preparation with ridge and/or chisel ploughing, adjustment of seed moisture content, seed treatment with mancozeb+metalaxyl and the water table control system, FOEAS. A unique success is seen in the tidal swamp area in South Sumatra with the Saturated Soil Culture (SSC), which is for managing acidity problem of pyrite soils. In 2016, an average yield of $2.4tha^{-1}$ was recorded for a 450 ha area with SSC (Ghulamahdi 2017, personal communication). This is a sort of raised bed culture and thus the moisture condition is kept markedly stable during growth period. For genetic control, too, many attempts are on-going for better emergence and plant growth after emergence under excess water. There seems to exist two aspects of excess water resistance, one related to phytophthora resistance and the other with better growth under excess water. The improvement for the latter is particularly challenging and genomic approach is expected to be effectively utilized. The crop model simulation would estimate/evaluate the impact of environmental and genetic factors. But comprehensive crop models for soybean are mainly for cultivations on upland fields and crop response to excess water is not fully accounted for. A soybean model for production on drained paddy fields under monsoon climate is demanded to coordinate technological development under changing climate. We recently recognized that the yield potential of recent US cultivars is greater than that of Japanese cultivars and this also may be responsible for different yield trends. Cultivar comparisons proved that higher yields are associated with greater biomass production specifically during early seed filling, in which high and well sustained activity of leaf gas exchange is related. In fact, the leaf stomatal conductance is considered to have been improved during last a couple of decades in the USA through selections for high yield in several crop species. It is suspected that priority to product quality of soybean as food crop, especially large seed size in Japan, did not allow efficient improvement of productivity. We also recently found a substantial variation of yielding performance under an environment of Indonesia among divergent cultivars from tropical and temperate regions through in a part biomass productivity. Gas exchange activity again seems to be involved. Unlike in North America where transpiration adjustment is considered necessary to avoid terminal drought, under the monsoon climate with wet summer plants with higher activity of gas exchange than current level might be advantageous. In order to explore higher or better-adjusted canopy function, the methodological development is demanded for canopy-level evaluation of transpiration activity. The stagnation of soybean yield would be broken through controlling variable water environment and breeding efforts to improve the quality-oriented cultivars for stable and high yield.

• Korean Journal of Poultry Science
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• v.41 no.2
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• pp.99-104
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• 2014

The objective of this study is to analyze the production of extra-large egg and assess the impacts of exogenous factors in feeding the layer chicken. The main results of this study are as follows; First, feeding rations on the basics of statistics, internal maximum and minimum temperature and, the age at first egg affect the production of extra-large egg. Second, implicating the standardized coefficients from the conclusion of regression model estimating suggest that the amount of feed has the greatest impact on production followed by the age at first egg. Third, by using the elasticity of output and the volatility in the production, the result suggest that among the independent variable factors in the external volatility, the biggest one goes to feed ration, and the age at first egg follows. In order to control the production volatility in the extra-large egg production of the farms, it is necessary to manage an efficient feeding based on feed ration, age at first egg and, the maximum and minimum temperature inside the farm. Taken together, the results demonstrates that it should be concentrated by controlling the exogenous factors affecting extra large egg production and the management system construct, to increase extra-large egg production and the income of farmers at the same time.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.4
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• pp.67-80
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• 2015

Although recent policies and regulations in Korea strongly advocate and encourage cultivation of venture foundations, studies on venture foundation and success are very limited and often primarily focus on entrepreneurship or individual quality as a venture founder in addition to such studies' validity in question. Therefore, this study primarily focuses on venture preparation process which is subject to venture founder's effort to verify the policy effectiveness in the relationship between venture preparation and business performance. Major goal of this study is to reduce social cost of venture failure by suggesting systematic policy support for venture foundations and analyzing the relationship between following variables: first, venture preparation and financial performance, second, venture preparation and non-financial performance, and third, venture preparation and business performance. 400 initial venture foundations less than 5 years are selected from KISED(Korea Institute Startup & Entrepreneurship Development) trend analysis to carry out statistical analysis using SPSS 18.0. To organize the data features, frequency analysis as well as descriptive statistics are performed to verify the hypothesis. As a result, sub-factors in measurement of venture preparation which are venture education period, venture benefit, and experience of incubating organization are selected as independent variables. Likewise, sub-factors in measurement of business performance which are financial performance and non-financial performance are used as dependent variables. To validate interactive effect, venture preparation period is selected as control variable to perform hierarchical regression analysis. The analysis result verifies that venture benefit has positive influence on financial and non-financial performance while venture education period has positive influence on non-financial influence and experience of incubating organization has negative influence on non-financial performance without influence on financial performance. In addition, interaction of venture preparation period has positive influence solely between venture benefit and non-financial performance. Through this study, appropriate supporting plans depending on the level of venture preparation can be derived to improve business performance of initial venture foundations for policy designer of venture support, and quality rather than quality improvement of venture businesses is possible through investigation of structural issues of individual venture businesses. Ultimately, this study suggests venture founders to determine whether to focus on venture preparation process or to start a venture business.

• Korean Journal of Biological Psychiatry
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• v.9 no.2
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• pp.140-151
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• 2002

Object and Method:Minor physical anomalies(MPAs) are frequently seen in patients with schizophrenia. MPAs are considered to arise from the anomalous development of ectoderm-originated tissues in the developing fetus. Since the central nervous system originates from ectoderm, MPAs can be regarded as externally observable and objective indicators of the aberrant development which might have taken place in the central nervous system. To investigate whether MPAs are more frequent in schizophrenic patients, the frequencies of MPAs were compared between schizophrenic patients and normal controls. Total 245 schizophrenic patients diagnosed with DSM-IV(male : 158, female : 87), and 418 normal control subjects(male : 216, female : 202) were included in this study. The MPAs were measured using the modified Waldrop scale with fifteen items in six bodily regions; head, eye, ear, mouth, hand, and foot. Result:The total scores of Waldrop scale were $4.40{\pm}1.93$($mean{\pm}standard$ deviation) in patients and $3.43{\pm}1.68$ in controls for females, and for males, $4.58{\pm}1.75$ in patients and $4.28{\pm}1.59$ in controls. For females, the excess of MPAs in schizophrenic patients was statistically significant(t-test : p<0.001). For males, schizophrenic patients also showed more MPAs than normal controls, but this tendency did not reach statistical significance (t-test : p=0.094). When the modified Waldrop total scores excluding head circumference were compared, the total scores in schizophrenic patients were significantly higher for both male and female subjects(t-test : male p<0.001, female p=0.001). The individual anomaly items included in Waldrop scale were also investigated. The items of epicanthus, hypertelorism, malformed ears, syndactylia were significantly more frequent in schizophrenic patients. In contrast, the items of adherent ear lobes, asymmetric ears, furrowed tongue, curved fifth finger, single palmar crease and big gap between toes did not show any differences in frequency between schizophrenic patients and normal controls. Since a lot of statistical analyses showed different results between male and female subjects, it seems to be necessary to consider gender as an important controlling variable for the analysis, however only the item of head circumference showed statistically significant gender-related difference according to log-linear analysis. Conclusion:With a relatively large sample size, the frequencies of MPAs enlisted in Waldrop scale were compared between schizophrenic patients and normal controls in this study. MPAs were more frequently seen in schizophrenic patients and, especially, several specific items in the Waldrop scale showed prominent excess in schizophrenic patients. Although definite conclusions cannot be drawn due to the inherent limitation of the study using Waldrop scale, these results seem to support the possibility that aberrant neurodevelopmental process might be involved in the pathogenesis of schizophrenia in some of the patients.

• The Korean Journal of Financial Management
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• v.25 no.4
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• pp.25-51
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• 2008

In this paper, we analyse empirically the fixed asset investment smoothing of working capital of firms listed on Korea Securities Market. The main results of this study can be summarized as follows. Firms will seek to lower long-term cost by smoothing fixed asset investment and maintaining stationary investment with working capital. Working capital is not only an important use of fund, but also a source of liquidity that should be used to smooth fixed asset investment relative to cash flow shocks if firms face financial constraints. Working capital investment is more sensitive than fixed asset investment to cash flow fluctuations. If firms face financial constraints, working capital investment will compete with fixed asset investment for the limited pool of available cash flows. So, fixed asset investment will have negative relationship with working capital investment. However, criticism that the positive correlation between cash flows and fixed asset investment could arise simply because cash flows is proxy variable for investment demand. Finally, controlling for the fixed asset investment smoothing effects of working capital results in a much larger estimate of the long run impact of financial constraints. Financial constraints is measured by dividend payout ratio and market access level. Fazzari et al. (1988), Fazzari and Petersen (1993), and Faulkender et al. (2008) emphasize that low dividend firms or market unaccessible firms are more likely to face financial constraints, and rarely make use of new equity issuing. The results from empirical analysis show that financial constraints can be better explained using 'adjustment cost' concept. Specifically, the results show that financial constraints exist and that in order to measure financial constraint effects more succinctly, fixed asset investment smoothing effects with working capital should be considered.

• Journal of Korean Society of Forest Science
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• v.87 no.4
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• pp.519-527
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• 1998

An economic study of vegetation control to increase production of Songyi (Korean name far pine mushroom, matsutake, Tracholoma matsutake (S. Ito & Imai) Sing.) in red pine (Panes densiflora) stands in Korea was undertaken. In Korea, Songyi grows only in red pine stands. Harvest of this mushroom provides a significant income source to rural people in Korea yielding exports of US$20 million to US$80 million per year. However, hypogeous Songyi colonies and the mushroom production are declining, partly because shade tolerant species are succeeding the shade intolerant red pine. Past research says that it is possible to deep Songyi production increasing by controlling under-story vegetation. But few people are wilting to invest in the necessary control. Our analysis found that the economics of vegetation control appear to be quite favorable, showing an internal rate of return (IRR) of 20.7 percent in 15 years. However, positive returns do not occur for at least eight years and even then, the returns may not appear to the landowner to be a result of vegetation control efforts only because the mushroom production has been greatly variable depending on weather conditions. In a sensitivity analysis, it was found that the number of circular mushroom colonies was critically important for the cash flow. Results of this analysis are also sensitive to assumptions about annual growth length(0.16m radial growth=1.0m/circular length growth) of Songyi colony. However, the primary goal of vegetation control should be to keep the young colonies growing. Further research in the behavior of hypogeous Songyi colonies after vegetation control would help to improve our confidence in the results.

• The Korean Journal of Archival Studies
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• no.12
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• pp.81-135
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• 2005

The release of administrative information has been the challenge of our age following the maturation of democratic ideology in our society. However, differences of opinion and conflict still exist between the government and private sectors regarding the issue, and it seems that the technical and policy-related insufficiencies of information and record management that actually operate the release of information are the main causes. From the perspective of records management, records or information are variable in their nature, value, and influence during their life span. The most controversial issue is the records and information in the current stage of carrying out business activities. This is because the records and information pertaining to finished business are but evidence to ascertain the past, and have only a limited relationship to the ideal of the 'democratic participation' by citizens in activities of the public sector. The current information release policies are helpless against the 'absence of information,' or incomplete records, but such weakness can be supplemented by enforcing record management policies that make obligatory the recording of all details of business activities. In addition, it is understood that the installation of 'document offices("Jaryogwan")' that can manage each organization's information and records will be an important starting point to integrate the release, management, and preservation of information and records. Nevertheless, it seems that the concept of 'release' in information release policies refers not to free use by all citizens but is limited to the 'provision' of records according to public requests, and the concept of 'confidential' refers not to treating documents with total secrecy but varies according to the particulars of each situation, making the actual practice of information release difficult. To solve such problems, it is absolutely necessary to collect the opinions of various constituents associated with the recorded information in question, and to effectively mediate the collective opinions and the information release requests coming from applicants, to carry out the business more practically. Especially crucial is the management of the process by which the nature and influence of recorded information changes, so that information which has to be confidential at first may become available for inquiry and use over time through appropriate procedures. Such processes are also part of the duties that record management, which is in charge of the entire life span of documents, must perform. All created records will be captured within a record management system, and the record creation data thus collected will be used as a guide for inquiry and usage. With 'document offices(Jaryogwan)' and 'archives' controlling the entire life span of records, the release of information will become simpler and more widespread. It is undesirable to try to control only through information release policies those records the nature of which has changed because, unlike the ones still in the early stages of their life span and can directly influence business activities, their work has finished, and they have become historical records or evidences pointing to the truth of past events. Even in the past, when there existed no formal policy regarding the release of administrative information, the access and use of archival records were permitted. A more active and expanded approach must be taken regarding the 'usage' of archival records. If the key factor regarding 'release' lies in the provision of information, the key factor regarding 'usage' lies in the quality and level of the service provided. The full-scale usage of archival records must be preceded by the release of such records, and accordingly, a thorough analysis of the nature, content, and value of the records and their changes must be implemented to guarantee the release of information before their use is requested. That must become a central task of document offices and "Today's information" will soon become "yesterday's records," and the "reality" of today will become "history" of the past. The policies of information release and record management share information records as their common objective. As they have a mutual relationship that is supplementary and leads toward perfection, the two policies must both be differentiated and integrated with each another. It is hoped that the policies and business activities of record management will soon become normalized and reformed for effective and fair release of information.