• Development and Reproduction
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• v.20 no.4
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• pp.289-296
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• 2016

This report describes the sex differentiation of the Korean rose bitterling, Rhodeus uyekii, from hatching to 170 days post-hatch (DPH) in relation to total length (TL), body weight (BW), and integral water temperature (IWT). The growth curve of TL from just hatching to 83 DPH was $5.144e^{0.045t}$ ($R^2=0.961$; t, time), and that of BW was $2.398e^{0.086t}$ ($R^2=0.725$). Primordial germ cells (PGCs) were observed at 17 DPH (7.9 mm TL, 3.74 mg BW, $374^{\circ}C$ IWT), and thereafter began to protrude into the peritoneal cavity. At 21 DPH ($9.2{\pm}0.14mm$ TL, $4.8{\pm}0.07mg$ BW, $462^{\circ}C$ IWT), some PGCs contained condensed chromatin and oocyte were observed in meiotic prophase. In contrast to the ovaries, which grew gradually after sexual differentiation, testes began multiplying at 25 DPH (10.1 mm TL, 5.42 mg BW, $550^{\circ}C$ IWT), when testicular differentiation was first identified, and multiplied continuously thereafter. At 33 DPH (11.2 mm TL, 10.5 mg BW, $726^{\circ}C$ IWT), the developing testes contained spermatogonia that exhibited mitotic activity. No spermatocyte or sperm cell was observed until 83 DPH (18.9 TL, 48.2 mg BW, $1,826^{\circ}C$ IWT). At 170 DPH (32.5 mm TL, 270.1 mg BW, $3,740^{\circ}C$ IWT), which was the end point of this study, the mature ovaries showed germinal vesicle breakdown, while the mature testes contained observable spermatocytes and sperm cells. These results allow us to identify the sex differentiation type of the Korean rose bitterling as differentiated gonochoristic.

• Journal of Korean Society of Transportation
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• v.27 no.4
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• pp.115-126
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• 2009

The lane-change behavior usually consists of discretionary lane-change and mandatory lane-change types. For the first type, drivers change lanes selectively to maintain their own driving condition and the second type is the case that the drivers must change the current lane, which can occur in recurrent congestion sections like merging and weaving sections. The mandatory lane-change behavior have a great effect on the operation condition of freeway. In this paper, we first generate data such as traffic volumes, speeds, densities, and the number of lane-change within the merging and weaving sections using the data of individual vehicle collected from time-lapse aerial photography. And then, the data is divided into the stable and congested flow by analyzing the speed variation pattern of individual vehicles. In addition, the number of lane-changing from ramp to mainline within every 30-meter interval is investigated before and after traffic congestion at study sites and the distribution of lane-changing at each 30-meter point is analyzed to identify the variation of lane-changing ratio depending on the stable and congested flows. To recognize the effect of mainline flow influenced by ramp flow, this study also analyzes the characteristics of the lane-changing distributions within the lanes of mainline. The purpose of this paper is to present the basic theory to be used in developing a lane-changing model at the merging and weaving sections on freeways.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.800-804
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• 1997

To evaluate the characters related to rice grain quality as affected by silicate application, the ripened color, appearence and physicochemical properties of rice grain which were produced at the silt-loam paddy field of National Yeongnam Agricultural Exeperiment Station with a little poor drainage for trials on long-term effects of continuous application of same fertilizer were analyzed comparing with the NPK fertilizer an the NPK＋compost in 1995. The whiteness value and color space value in ripened color of rice hull by silicate application were higher than those in the plots of NPK and NPK＋compost, because of low percentage of rusty grain and sooty grain, The percentage of perfect grain in brown rice and in milled rice by the silicate application increased by 6.1~7.5% and by 1.8~3.5% respectively, as compared with the NPK application and white core and white belly of milled rice were decreased, The amylose content, protein content and starch-iodine blue value of milled rice by silicate application were lower than those in the plots of NPK and NPK＋compost, while the peak point and breakdown viscosity of gelatinized rice flour on amylograph, and tastes value evaluated as a indicater of pannel test by nireco tester were higher. By silicate application these factors could be affected toward better in eating quality.

• The Journal of the Korea Contents Association
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• v.16 no.1
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• pp.24-41
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• 2016

Study is about Bit Coin that is electronic cash that is received attention globally in recent. It is increasing domestically that uses bit coin for convenience of micro payment, and also bit coin is possible to exchange each countries' currency. In this point, we searched understanding degree and acceptance of bit coin. Also we applied transformed TAM(Technology Acceptance Model) to search factors that have an effect on consumers' intention to use it. In advance, we analyze features of bit coin, and extract factors through preceding researches for existing electronic cash, because studies for intention to use bit coin are weak in internal and external. First of results is that 'economic efficiency' which is a characteristic variable of bit coin influences 'intention to use,' a dependent variable through 'perceived usefulness,' a parameter. It was investigated that monetary and mental costs that was costed when we use bit coin were less than using other cash. Secondly, 'payment convenience' that is a characteristic variable affects 'intention to use', a dependent variable through 'perceived usefulness,' a parameter. It was measured that problems of inconvenience that include transaction process, cash management time shortage and exchange changes will be solved by using bit coin. Thirdly, 'reliability' that is a perceived risk variable of bit coin has a direct effect on 'intention to use,' a dependent variable. It was investigated that we could achieve purpose of payment because we weren't influenced by breakdown on system by processing distributed database in some computers. Fourthly, 'perceived usefulness,' a parameter of bit coin directly affects 'intention to use,' a dependent variable. Then consumers who want to use bit coin are fascinated bit coin for various usability. Moreover, we want to provide implications to all of finance corporations, companies related electronic cash and bit coin users based on these results.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.399-405
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• 2011

In this study, we evaluated the fruit quality indices and the incidence of physiological disorders of Korean new pear cultivar 'Whasan' to determine appropriate harvest time for exportation and to enhance storability and shelf-life of the fruits during simulated exportation and extending market environment under different temperature conditions. In the experiment of simulated exportation headed for North America including Canada and U.S.A., the fruits transported at $1^{\circ}C$ showed less weight loss than those of $5^{\circ}C$. Market temperature appeared as a key factor for keeping freshness of exported pear fruits rather than transportation temperature. Quality factors such as high flesh firmness and low incidence of fruit rot and physiological disorders including core breakdown and pithiness were attained at the fruits maintained at $18^{\circ}C$ when we compared with $25^{\circ}C$. The fruits of harvested early maturity at 135 day after full bloom showed 28.6 N of flesh firmness when the fruits stored at $1^{\circ}C$ of transportation and $18^{\circ}C$ of market temperature, while the fruits progressed $5^{\circ}C$ of transportation and $25^{\circ}C$ of market temperature dropped to 24.2 N during 30 days of shelf life. Also, a high incidences of physiological disorders and of fruit decay rates were obvious in the fruits distributed at $25^{\circ}C$ were observed approximately two times higher than the those of $18^{\circ}C$. Therefore, temperature management during marketing resulted as an important point for maintaining fruits quality in the process of pear fruit exportation.

• Korean Journal of Social Welfare
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• v.53
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• pp.31-49
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• 2003

Neo-liberalism, the most influential ideology in the current world, argues for the commercialization of social security programs and for the dissolution of the interventionist welfare state. From the neo-liberal viewpoint, social services become more efficient and more advantageous for recipients, when provided by the market, not by the state. It is also argued that the welfare of all social members is best secured when the market freely operates without any interference from the state. From the neo-liberal point of view, an argument was raised to commercialize the state-administered Workers' Compensation program of Korea in the mid-1990s. This argument was faced with strong resistances from labor unions and social welfare circles, and has disappeared since the economic breakdown and the restructuring of Korean society during the late 1990s. Butr, such an argument can emerge anytime as the nee-liberal ideology become more powerful. This article aims to examine the neo-liberal argument that the privatization of social security programs, through an increases in efficiency, improves the interests of the recipients as well as the whole society. For this, this article attempts to analyze the Workers' Compensation programs of the USA, which, from state to state, are administered by the state government or by private insurance companies. This study can serve as an effective critique for the neo-liberal argument, if it finds that state-administered Workers' Compensation programs are more efficient than those managed by insurance companies. This article's another aim is to assess the controversies over the privatization of the Workers' Compensation program of Korea during the mid to late 1990s. The controversies were more about which viewpoint is right and, in most cases, lacked empirical evidence. This study shall empirically criticize the argument for the privatization of the Workers' Compensation program.

• Journal of Distribution Science
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• v.9 no.3
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• pp.83-94
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• 2011

Most domestic companies, with the exclusion of major firms, are reluctant to implement a supply chain management (SCM) network into their operations. Most small- and medium-sized enterprises are not even aware of SCM. Due to the inherent total-systems efficiency of SCM, it coordinates domestic manufacturers, subcontractors, distributors, and physical distributors and cuts down on cost of inventory control, as well as demand management. Furthermore, a lack of SCM causes a decrease in competitiveness for domestic companies. The reason lies in the fundamentality of SCM, which is the characteristic of information sharing, process innovation throughout SCM, and the vast range of problems the SCM management tool is able to address. This study suggests the contemplation and reformation of the current SCM situation by analyzing the SCM strategic plan, discourses and logical discussions on the topic, and a successful case for adapting SCM; hence, the study plans to productively "process" SCM. First, it is necessary to contemplate the theoretical background of SCM before discussing how to successfully process SCM. I will describe the concept and background of SCM in Chapter 2, with a definition of SCM, types of SCM promotional activities, fields of SCM, necessity of applying SCM, and the effects of SCM. All of the defects in currently processing SCM will be introduced in Chapter 3. Discussion items include the following: the Bullwhip Effect; the breakdown in supply chain and sales networks due to e-business; the issue that even though the key to a successful SCM is cooperation between the production and distribution company, during the process of SCM, the companies, many times, put their profits first, resulting in a possible defect in demands estimation. Furthermore, the problems of processing SCM in a domestic distribution-production company concern Information Technology; for example, the new system introduced to the company is not compatible with the pre-existing document architecture. Second, for effective management, distribution and production companies should cooperate and enhance their partnership in the aspect of the corporation; however, in reality, this seldom occurs. Third, in the aspect of the work process, introducing SCM could provoke corporations during the integration of the distribution-production process. Fourth, to increase the achievement of the SCM strategy process, they need to set up a cross-functional team; however, many times, business partners lack the cooperation and business-information sharing tools necessary to effect the transition to SCM. Chapter 4 will address an SCM strategic plan and a case study of LG Electronics. The purpose of the strategic plan, strategic plans for types of business, adopting SCM in a distribution company, and the global supply chain process of LG Electronics will be introduced. The conclusion of the study is located in Chapter 5, which addresses the issue of the fierce competition that companies currently face in the global market environment and their increased investment in SCM, in order to better cope with short product life cycle and high customer expectations. The SCM management system has evolved through the adaptation of improved information, communication, and transportation technologies; now, it demands the utilization of various strategic resources. The introduction of SCM provides benefits to the management of a network of interconnected businesses by securing customer loyalty with cost and time savings, derived through the consolidation of many distribution systems; additionally, SCM helps enterprises form a wide range of marketing strategies. Thus, we could conclude that not only the distributors but all types of businesses should adopt the systems approach to supply chain strategies. SCM deals with the basic stream of distribution and increases the value of a company by replacing physical distribution with information. By the company obtaining and sharing ready information, it is able to create customer satisfaction at the end point of delivery to the consumer.

• Korean Journal of Agricultural Science
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• v.12 no.2
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• pp.356-369
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• 1985

In Korea, inevitable researches for the blast control exactly started from 1927 by the organization of Office of Rural Development with the local extensive outbreak of panicle blast at Jeonlla Buk-Do Province in 1926. At present, the rice blast is still one of the most destructive and widespread diseases in spite of considerable contributions by rice scientists, particularly plant pathologists during last 55 years in Korea. Rice blast control and management are very difficult because of the marked variability in pathogenicity of the blast fungus. From the results obtained through the disease surveys during last 70 years, different 3 prevalence type of blast such as bimodal leaf-blast type, bimodal panicle-blast type and bimodal continual blast type were recognized. In generally speaking, pattern of blast outbreak is said to be characterized by severe outbreak of panicle blast after slight outbreak of leaf blast with discontinuity between leaf and panicle blast. So we have to pay much attention for successful management of panicle blast giving direct influence to rice yield. Main factors induce blast epidemic were pointed out to be breakdown of the disease resistance, nutritional unbalance such as excess application of nitrogen, delay of transplantation and longspell of rain fall by extensive surveys and researches on blast during last 70 years in Korea. The fact some of Japonica varieties such as Kokuryomiyako, Tamanishiki, Ginbozu and Pungok belong to varietal group A had been cultivated with extensive acrage over 30 years in this country should be mentioned by Korean rice scientists. Differences in field resistance between varieties in the same group are detectable and apparently small but sometimes epidemiologically significant differential effects may be found out in case of blast. Much more attention should be payed to accumulate the knowledges on field resistance for successful management of blast. Excess application of nitrogen is more effective to outbreak of panicle blast than that of leaf blast of IR varieties. In comparatively low level application of nitrogen infection rate of panicle blast of IR varieties is considerably high. Low temperature effects on outbreak of blast is very great. It results in remarkable increase of the inoculum potential on the leaf lesions and infection of panicle blast in leaf sheathes of IR varieties during the booting stage. In economic point of view, it is concluded that 5 times sprays of effective fungicides including 3 times before and 2 times after heading is good enough to control blast. We have experienced no one of control measures for blast is superior to all others. The integrated control measures was established as guideline of blast control around 1950 in Korea. This guideline must be helpful for rice growers as long as rice growing continue.