• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.2
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• pp.61-71
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• 2009

Most deciduous trees in temperate zone are dormant during the winter to overcome cold and dry environment. Dormancy of deciduous fruit trees is usually separated into a period of rest by physiological conditions and a period of quiescence by unfavorable environmental conditions. Inconsistent and fewer budburst in pear orchards has been reported recently in South Korea and Japan and the insufficient chilling due to warmer winters is suspected to play a role. An accurate prediction of the flowering time under the climate change scenarios may be critical to the planning of adaptation strategy for the pear industry in the future. However, existing methods for the prediction of budburst depend on the spring temperature, neglecting potential effects of warmer winters on the rest release and subsequent budburst. We adapted a dormancy clock model which uses daily temperature data to calculate the thermal time for simulating winter phenology of deciduous trees and tested the feasibility of this model in predicting budburst and flowering of Niitaka pear, one of the favorite cultivars in Korea. In order to derive the model parameter values suitable for Niitaka, the mean time for the rest release was estimated by observing budburst of field collected twigs in a controlled environment. The thermal time (in chill-days) was calculated and accumulated by a predefined temperature range from fall harvest until the chilling requirement (maximum accumulated chill-days in a negative number) is met. The chilling requirement is then offset by anti-chill days (in positive numbers) until the accumulated chill-days become null, which is assumed to be the budburst date. Calculations were repeated with arbitrary threshold temperatures from $4^{\circ}C$ to $10^{\circ}C$ (at an interval of 0.1), and a set of threshold temperature and chilling requirement was selected when the estimated budburst date coincides with the field observation. A heating requirement (in accumulation of anti-chill days since budburst) for flowering was also determined from an experiment based on historical observations. The dormancy clock model optimized with the selected parameter values was used to predict flowering of Niitaka pear grown in Suwon for the recent 9 years. The predicted dates for full bloom were within the range of the observed dates with 1.9 days of root mean square error.

• The Korean Journal of Air & Space Law and Policy
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• v.33 no.1
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• pp.81-120
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• 2018

To promote the aviation safety reporting system that is operated to enhance aviation safety and to utilize related information, it should first be preceded by standards for non-punishment and data protection. It is because the purpose of collection and analysis of aviation safety related data through the aviation safety reporting system is to prevent recurrence of accidents by investigating their causes through collection and analysis of diverse types of information related to aviation safety. Both mandatory and voluntary reporting systems are in operation for aviation safety under the current Aviation Safety Act. It is said that they were introduced to survey causes for accidents and to prevent recurrences. In fact, however, it is hard to expect active implementation of the reporting system for aviation safety unless the reporters are firstly exempted from punishment. Therefore, the system should be improved so that it can satisfy its purpose and the purposes of data collection concerning aviation safety through examination of the purposes of the reporting system. One of the matters that needs to be considered to promote the reporting system should be the scope of aviation safety hindrances presupposed under the current institution. The voluntary aviation safety reporting system differs from the systems of ICAO or the key advanced countries, including the USA and the UK as it limits the target accidents subject to reporting to minor aviation safety hindrances only. That being said, improvements should be made by requiring mandatory reporting of aviation safety hindrances based on their severity while recognizing a greater variety of aviation safety concerns like international standards. Safety actions and sharing of information based on collection and analysis of diverse data related to aviation safety will greatly contribute to enhance aviation safety as the purposes of the reporting system are to explore causes for accidents and to prevent their recurrences. What is most important in this regard is strict data protection and non-punishment principles; compliance with them should be secured. We can hardly expect the successful operation of the system unless the reporter is exempted from punishment and the relevant data is protected as promotion of voluntary reporting is an essential factor for enhancing the safety culture. Otherwise, the current system may induce hiding of relevant facts or data to evade punishment. It is true that the regulation for enhancing safety tends to have limitations or blind spots; nevertheless, it should still be enforced strictly and completely. Technological progresses and mistakes of operators appear in different forms based on individual cases. The consequential damages may amount to a truly severe level. Therefore, we have studied and suggested to the methods of activiation and amendments on the aviation safety reporting system, which is referred for one of the proactive safety management systems. The proposed improvement of the reporting system and introduction of non-punishment for collection of aviation safety data for deploying a preemptive prevention system would serve as the backbone for enhancing aviation safety in Korea.

• Journal of Veterinary Clinics
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• v.29 no.5
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• pp.377-383
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• 2012

Bovine diarrhea is a major economical burden to the bovine industry in Korea. Since multiple infectious agents can be involved in bovine diarrhea, differential diagnosis is essential for effective treatment. Therefore, a panel of two multiplex real-time PCR assays which can simultaneously detect six major bovine enteric pathogens [i.e., bovine viral diarrhea virus (BVDV), bovine coronavirus (BCoV), group A bovine rotavirus (BRV), Salmonella spp., Escherichia coli (E. coli) $K99^+$, and Cryptosporidium parvum] was developed and applied to test 97 fecal samples collected from cattle farms in Korea. In addition, microscopic examination was also preformed on the samples to detect Coccidium oocyst. The estimated sensitivity of the multiplex PCR was 0.1 $TCID_{50}$ for BVDV, BCoV and group A BRV, 5 and 0.5 CFU for E. coli $K99^+$ and Salmonella, respectively, and 50 oocysts for Cryptosporidium. The amplification efficiency of the multiplex PCR ranged between 0.97 and 0.99 for each pathogen. Among 97 samples, 36 samples were positive for at least one of the 6 major pathogens and 6 samples were simultaneously positive for 2 pathogens by the multiplex PCR assay. Coccidium oocysts were also detected in 48 samples, which were all collected from over 1 month old calves. In conclusion, the multiplex real-time PCR panel can be a useful tool for fast and accurate diagnosis of calf diarrhea associated with BVDV, BCoV, group A BRV, E. coli $K99^+$, Salmonella, and/or Cryptosporidium and Coccidium may be an important target which needs to be included in the multiplex PCR panel in the future.

• The Korean Journal of Air & Space Law and Policy
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• v.26 no.1
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• pp.271-297
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• 2011

Recently, risk of space accident possibility increased in according to commercial space activity and space debris. It failed launch satellite second times in South Korea. Therefore was discussed on liability and insurance issue. Generally, discuss of space insurance be divided two type. Firstly, space insurance relevant to launching satellite and in-orbit. Satellite Launch Insurance and In-Orbit Insurance by the Satellite Operator Secondly, space insurance relevant to Third Party Liability. The former is to protect owner of satellite and operator. The latter is to liable and indemnify owner of satellite and operator's liability. US, UK, France, Russia, South Korea forced to buy space insurance following to domestic law. This is a brief overview of risk allocation and insurance practices in the commercial space transportation industry today. We begin with traditional space transportation, i.e., commercial satellite launches. This is a mature industry with known players. Industry practices have developed and legislation has been adopted in the U.S. and other countries over the past decades to address liability and insurance issues. The primary focus here is on U.S. law, but the discussion of industry practice applies more generally. We then move on to a more exotic form of space transportation: Commercial human space flight. Several private companies are now signing up space tourists for commercial suborbital human space flight, advertised to become available in the near future. The United States amended its launch legislation in 2004 to promote commercial human space flight. But questions remain as to how this new industry will respond to the risk allocation regime established by the U.S. legislation, which leaves both the space flight operator and space tourist exposed to risk and potential liability. As a general proposition, state statutes and contractual waivers alone cannot be relied upon to provide adequate liability protection, and insurance will be required. Federally mandated contractual waivers by space flight participants or liability caps would be helpful to complement insurance solutions. Eventually, as the industry matures, such practices could be extended to an international legal regime. For all the issues mentioned above, I have studied the existing international treaties and several country's domestic law to the space by referring U.S's Commercial Space Launch Amendment Act of 2004 and concluded that uniform legal regime to govern these insurance issues should be established domestically and internationally in the future.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.1
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• pp.120-128
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• 2018

The purpose of this study is to establish basic data for the continuous protection management policy of domestic natural world heritage and mixed world heritage, and to examine the present situation and characteristics of the protection management according to the World Heritage Convention on the World Heritage listed Huangshan. The results of this study are as follows. First, Huangshan began to be protected by the establishment of the Huangshan Construction Committee in 1933, and after the designation of national park in 1982, laws and regulations were established in the central ministries, And various projects related to utilization have been implemented. Secondly, the establishment of the boundary for protection was actively intervened by the central government, such as the reorganization of the boundary of Huangshan through the administrative district plan. In order to protect the ecological and landscape value as well as the cultural factor, And designated a heritage designated area. Third, the protection management of Huangshan was divided into four major stages. The first phase was divided into the period when administrative measures were taken to manage the protection of Huangshan. The second phase was designated as a national park in Huangshan. The third period was the time of the protection-oriented project according to the recommendation of the international organizations after the World Heritage listed. The fourth period was the expansion of the tourism industry for the continuous use of protection of Huangshan city, My preservation business was being implemented. Fourth, Huangshan is managed by the central government and the city government. Huangshan, which is a mixed heritage, is managed jointly by the Ministry of Cultural Heritage Administration and the Ministry of Natural Heritage Administration. The protection and management of Huangshan promoted the efficiency and expertise of the heritage-related work through the establishment of the administrative unit-specific management system, and the local governments were entrusted with the authority to implement the protection management policies that meet local characteristics. Fifth, the preservation area of Huangshan has been destroyed by the development policy centered on the mountain. In addition, according to the operation of accommodation facilities, there are problems such as sewage, garbage disposal, and environmental pollution caused by tourists, and the damage caused by pests and diseases in planted plantations around the area and changes in ecosystem due to the composition of cable cars. Sixth, for the continuous protection of Huangshan, strict regulations on new construction, extension and management of accommodation are required, and it is necessary to install facilities to limit and control the number of visitors.

• Journal of Korean Society of Transportation
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• v.19 no.1
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• pp.101-114
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• 2001

Transportation enterprises should maintain constant and qualitative operation. Thus, in short period, transportation enterprises don't change supply in accordance with demand. In the result, transportation enterprises don't reduce operation in spite of management deficit at will. In freight transportation type, less-than-truckload(LTL) has more relation with above transportation feature than truckload(TL) does. Because freight transportation supply of TL is more flexible than that of LTL in correspondence of freight transportation demand. Relating to above mention, it appears that shortage of road and freight terminal of LTL is larger than that of TL. Especially in road and freight terminal comparison, shortage of freight terminal is larger than that of road. Shortage of road is the largest in 1990, and improved after-ward. But shortage of freight terminal is serious lately. So freight terminal needs more expansion than road, and shows better investment condition than road. Freight terminal expansion brings road expansion in LTL, on the contrary, freight terminal expansion substitutes freight terminal for road in TL. In transportation revenue, freight terminal's contribution to LTL is larger than that to TL. However, when we adjust quasi-fixed factor - road and freight terminal - to optimal level in the long run, in TL, diseconomies of scale becomes large, but in LTL, economies of scale becomes large. Consequently, it is necessary for TL to make counterplans to activate management of small size enterprises and owner drivers. And LTL should make use of economies of scale by solving the problem, such as nonprofit route, excess of rental freight handling of office, insufficiency of freight terminal, shortage of driver, and unpreparedness of freight insurance.

• Fire Science and Engineering
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• v.31 no.5
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• pp.53-62
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• 2017

Electric power which is the energy source of economy and industries requires long distance transportation due to regional difference between its production and consumption, and it is supplied through the multi-loop transmission and distribution system. Prior to its actual use, electric power flows through several transformations by voltage transformers in substations depending on the characteristics of each usage, and a transformer has the structure consisting of the main body, winding wire, insulating oil and bushings. A transformer fire that breaks out in substations entails the primary damage that interrupts the power supply to houses and commercial facilities and causes various safety accidents as well as the secondary economic losses. It is considered that causes of such fire include the leak of insulating oil resulting from the destruction of bottom part of bushings, and the chain reaction of fire due to insulating oil that reaches its ignition point within 1 second. The smoke detector and automatic fire extinguishing system are established in order to minimize fire damage, but a difficulty in securing golden time for extinguishing fire due to delay in the operation of detector and release of gas from the extinguishing system has become a problem. Accordingly, this study was carried out according to needs of active mechanism to prevent the spread of fire and block the leak of insulating oil, in accordance with the importance of securing golden time in extinguishing a fire in its early stage. A bushings fireproof structure was developed by applying the high temperature shape retention materials, which are expanded by flame, and mechanical flame cutoff devices. The bushings fireproof structure was installed on the transformer model produced by applying the actual standards of bushings and flange, and the full scale fire test was carried out. It was confirmed that the bushings fireproof structure operated at accurate position and height within 3 seconds from the flame initiation. It is considered that it could block the spread of flame effectively in the event of actual transformer fire.

• Journal of agriculture & life science
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• v.46 no.2
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• pp.179-190
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• 2012

This study was performed to obtain a heat saving effect and enhance the efficiency of a greenhouse by using a hot water piping in order to minimize the operating costs of a greenhouse as oil prices continue to rise. This method also reduces the likelihood of accidents caused by snowdrifts in regions with heavy snowfall. In general, the experimental plot was $2.0{\sim}6.0^{\circ}C$ higher than the control plot. When the skylight felt was opened, the minimum temperature was in the range of $3.0{\sim}12.0^{\circ}C$. Therefore, we judged that damage caused by snowdrifts may be prevented partly by active heating. The temperature difference inside of the greenhouse by height was insignificant. The maximum heating load of the greenhouse according to crop was respectively about $37,000kcal{\cdot}h^{-1}$ and $41,700kcal{\cdot}h^{-1}$. During the experiment, the heat value of each designed temperature in the range of the minimum ambient temperature $-11.9{\sim}4.0^{\circ}C$ was about 95,000~322,000 kcal and it was in the range of $6,050{\sim}20,900kcal{\cdot}h^{-1}$. If it is compared with the maximum heating load, it can be shown that about 15~56% of the heating energy can be supplied. The total heat value and the amount of power consumption were 2,629,025 kcal and 677.3 kWh respectively during the experiment. If it is heated with diesel, a fossil fuel, the consumption during the experiment was 291 L and the cost was 331,700won. Total cost of using electric power was about 24,400 won and it is shown that it is about 7.5% of the cost of diesel consumption. Also, if the total amount of power consumption is converted into energy, it is approximately 582,200 kcal and the energy was just about 22% of the total heat value.

• Korean Journal of Ichthyology
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• v.30 no.4
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• pp.194-204
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• 2018

In order to minimize the damage on the red sea bream Pagrus major by a harmful dinoflagellate Cochlodinium polykrikoides, we investigated the effect of feeding, starvation and stocking density on the survival rate, growth, growth restoration and physiological response of P. major exposure to C. polykrikoides. The experimental groups were divided into three groups such as F-HD (feeding and high density with $6.4kg/m^3$), S-HD (starvation and high density with $6.4kg/m^3$) and S-LD (starvation and low density with $3.2kg/m^3$) according to stocking density and starvation in marine cage ($11m{\times}11m{\times}5m$). The F-HD was fed throughout the experiment for 9 weeks, whereas S-HD and S-LD were not fed for 5 weeks and then refeeding for 4 weeks. Survival rate was the lowest in F-HD (85.5%) and S-LD was the highest (97.3%). The growth rates of S-HD and S-LD were significantly lower than F-HD during starvation period for 4 weeks, but rapidly recovered after feeding. The nutritional status such as ALB, TP, TCH, TG were similar to tendency of growth data. Ht, Hb, AST, ALT and GLU levels were significantly higher in the F-HD than in the starvation groups at the same time (in 3 week) during starvation period. But starvation groups did not differ during starvation period. As a result, F-HD is more sensitive to stress than S-HD and S-LD. Thus, during C. polykrikoides bloom period, starvation and stocking density control can help survival and growth restoration of the red sea bream.

• Korean Journal of Heritage: History & Science
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• v.43 no.1
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• pp.100-117
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• 2010

This study analyzed vegetation structure of natural monuments Koelreuteria paniculata community in search of a conservation and management plan. Plant sociological analysis of Koelreuteria paniculata community indicates that it can be classified into Achyranthes japonica subcommunity and Rhodotypos scandens subcommunity and Trachelospermum asiaticum var. intermedium subcommunity. While Koelreuteria paniculata community of Ahnmyeondo is composed of sub tree layer and herb layer, those of Pohang and Wando are composed of tree layer, Sub tree layer, shrub layer, herb layer. The results of tree vitality analysis showed that those in Ahnmyeondo appeared to be relatively low when compared to those in Pohang and Wando-gun. This can be understood in two different aspects: disease and insects vulnerability due to a relatively simple structure and lack of competitive species, and decreased vitality / natural branch losses due to crown competition arising from high density. The result of soil characteristics analysis showed that soil texture, soil pH, organic matter, $p_2O_5$, exchange positive ion were sufficient for tree growth while total nitrogen was not, so that discretion would be needed for fertilizer application. As there were damages of disease and inscet, but only for 10~15% of the entire area; it still requires consistent preconsideration. The study suggests the management methods for preservation of Koelreuteria paniculata community. First, securing designated areas is necessary in order to minimize environment deterioration due to surrounding development. Especially, for sections with decreased areas, expansion of designated areas through land purchase should also be considered. Second, artificial interference may affect the livestock. Therefore, monitoring of artificial interference is necessary, based on which protection projects must be conducted. Third, from analysis of young plants which influence the maintenance mechanisms of Koelreuteria paniculata community, a decrease compared to the prior year was observed; investigation is needed. Therefore, an active management policy through status examination of livestock such as germination and young plants is necessary.