• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2000.04a
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• pp.9-10
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• 2000

An important business-field of world-wide steel-industry is the coating of thin metal-sheets with zinc, zinc-aluminum and aluminum based materials. These products mostly go into automotive industry. in particular for the car-body. into building and construction industry as well as household appliances. Due to mass-production, the processing is done in large continuously operating plants where the mostly cold-rolled metal-strip as the substrate is handled in coils up to 40 tons unwind before and rolled up again after passing the processing plant which includes cleaning, annealing, hot-dip galvanizing / aluminizing and chemical treatment. In the liquid Zn, Zn-AI, AI-Zn and AI-Si bathes a combined action of corrosion and wear under high temperature and high stress onto the transfer components (rolls) accounts for major economic losses. Most critical here are the bearing systems of these rolls operating in the liquid system. Rolls in liquid system can not be avoided as they are needed to transfer the steel-strip into and out of the crucible. Since several years, ceramic roller bearings are tested here [1.2], however, in particular due to uncontrollable Slag-impurities within the hot bath [3], slide bearings are still expected to be of a higher potential [4]. The today's state of the art is the application of slide bearings based on Stellite\ulcorneragainst Stellite which is in general a 50-60 wt% Co-matrix with incorporated Cr- and W-carbides and other composites. Indeed Stellite is used as the bearing-material as of it's chemical properties (does not go into solution), the physical properties in particular with poor lubricating properties are not satisfying at all. To increase the Sliding behavior in the bearing system, about 0.15-0.2 wt% of lead has been added into the hot-bath in the past. Due to environmental regulations. this had to be reduced dramatically_ This together with the heavily increasing production rates expressed by increased velocity of the substrate-steel-band up to 200 m/min and increased tractate power up to 10 tons in modern plants. leads to life times of the bearings of a few up to several days only. To improve this situation. the Mechanical Alloying (MA) TeChnique [5.6.7.8] is used to prOduce advanced Stellite-based bearing materials. A lubricating phase is introduced into Stellite-powder-material by MA, the composite-powder-particles are coated by High Energy Milling (HEM) in order to produce bearing-bushes of approximately 12 kg by Sintering, Liquid Phase Sintering (LPS) and Hot Isostatic Pressing (HIP). The chemical and physical behavior of samples as well as the bearing systems in the hot galvanizing / aluminizing plant are discussed. DependenCies like lubricant material and composite, LPS-binder and composite, particle shape and PM-route with respect to achievable density. (temperature--) shock-reSistibility and corrosive-wear behavior will be described. The materials are characterized by particle size analysis (laser diffraction), scanning electron microscopy and X-ray diffraction. corrosive-wear behavior is determined using a special cylinder-in-bush apparatus (CIBA) as well as field-test in real production condition. Part I of this work describes the initial testing phase where different sample materials are produced, characterized, consolidated and tested in the CIBA under a common AI-Zn-system. The results are discussed and the material-system for the large components to be produced for the field test in real production condition is decided. Outlook: Part II of this work will describe the field test in a hot-dip-galvanizing/aluminizing plant of the mechanically alloyed bearing bushes under aluminum-rich liquid metal. Alter testing, the bushes will be characterized and obtained results with respect to wear. expected lifetime, surface roughness and infiltration will be discussed. Part III of this project will describe a second initial testing phase where the won results of part 1+11 will be transferred to the AI-Si system. Part IV of this project will describe the field test in a hot-dip-aluminizing plant of the mechanically alloyed bearing bushes under aluminum liquid metal. After testing. the bushes will be characterized and obtained results with respect to wear. expected lifetime, surface roughness and infiltration will be discussed.

• Journal of Chest Surgery
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• v.40 no.8
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• pp.529-535
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• 2007

Background: An imbalance between oxidants and antioxidants leads to oxidative stress, and this has been proposed to play an important role in the pathogenesis of lung neoplasm. Apurinic/apyrimidinic endonuclease-1/redox factor-1 (APE/ref-1) is a multifunctional protein involved in DNA base excision repair and the redox regulation of many transcription factors. However, the alteration of the expressed levels of APE/ref-1 in non-small cell lung cancer is unknown. Material and Method: Forty-nine patients with surgically resected non-small cell lung cancer (NSCLC) were included in this study. Immunohistochemical staining with APE/ref-1 antibodies was performed, and their expressions were analyzed via Western blotting for specific antibodies. Result: APE/ref-1 was localized at the nucleus and mainly in the non-tumor region of the NSCLC tissue specimens; it was expressed in the cytoplasm and nucleus of the NSCLC. The nuclear and cytoplasmic expressions of APE/ref-1 in lung cancers were markedly up-regulated in the NSCLC, and this was correlated with the clinical stage. Catalase, as first-line antioxidant defense, was dramatically decreased in the NSCLC. Conclusion: Taken together, our results suggest that APE/ref-1, and especially cytoplasmic APE/ref-1, was upregulated in the lung cancer regions, and this may contribute to the compensatory defense system against oxidative stress. A low expression of catalase might have fundamental effects on the extracellular redox state of lung tumors, along with the potential consequences for the tumors.

• Journal of Environmental Impact Assessment
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• v.26 no.6
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• pp.553-562
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• 2017

In these days, agricultural reservoirs are considered as a useful resource for recreational purposes, tour and cultural amenity for vicinity communities as well as irrigation water supply. However, many of the agricultural reservoirs are showing a eutrophic or hyper-eutrophic state and high level of organic contamination. In particular, about 44.7% of the aged agricultural reservoirs that constructed before 1945 exceed the water quality criteria for irrigational water use. In addition to external loading, internal nutrient loading from bottom sediment may play an important role in the nutrient budget of the aged reservoirs. The objectives of this study were to characterize variations of thermal structure of a shallow M reservoir (mean depth 1.7 m) and examine the potential of internal nutrient loading by continuous monitoring of vertical water temperature and dissolved oxygen (DO) concentration profiles in 2015 and 2016. The effect of internal loading on the total loading of the reservoir was evaluated by mass balance analysis. Results showed that a weak thermal stratification and a strong DO stratification were developed in the shallow M Reservoir. And, dynamic temporal variation in DO was observed at the bottom of the reservoir. Persistent hypoxic conditions (DO concentrations less than 2 mg/L) were established for 87 days and 98 days in 2015 and 2016, respectively, during the no-rainy summer periods. The DO concentrations intermittently increased during several events of atmospheric temperature drop and rainfall. According to the mass balance analysis, the amount of internal $PO_4-P$ loading from sediment to the overlying water were 37.9% and 39.7% of total loading during no-rainy season in 2015 and 2016, respectively on August when algae growth is enhanced with increasing water temperature. Consequently, supply of DO to the lower layer of the reservoir could be effective countermeasure to reduce nutrient release under the condition of persistent DO depletion in the bottom of the reservoir.

• Applied Biological Chemistry
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• v.45 no.2
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• pp.84-91
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• 2002

If contaminated river water is sprayed over the floodplain, organic matter and nitrogen would be removed by microbial processes in the rhizosphere of vegetation during the filtration through soil. In this study we tested the organic matter and nitrogen removal from contaminated river water by the floodplain filtration. Model system of floodplain was constructed using a PVC pipe (15 cm i.d. ${\times}$ 150 cm L) which was packed with a loamy sand soil collected from a floodplain in Nakdong river. The model system was instrumented with soil solution samplers and gas samplers. A river water collected from Omogcheon in Kyongsan was sprayed from top of the model system at three different rates. The concentration of organic matter, DO, $NO_3^-$, $NO_2^-$, $NH_4^+$, $N_2$ and $N_2O$, and redox potential were measured as a function of soil depth for 24 days after the system reached a steady state. When river water was sprayed at the rates of 40.8 and 68.0 $l/m^2/day$, a significant reductive condition for denitrification was developed at below 5-cm depth of the soil. When the water reached at 90-cm depth of the soil, COD and concentration of inorganic nitrogen were lowered, on an average, from 18.7 to 5 mg/l and from 2.7 to 0.4 mg/l, respectively. $N_2$ comprised most of the N gas evolved from denitrification and $N_2O$ concentrations emitted at the surface of soil were less than 1 {\mu}l/l. The effective removal of organic matter and nitrogen by the filtration in the model system of floodplain demonstrates that the native floodplains, which include rhizosphere of vegetation at the top soil, could be more effective in the treatment of contaminated river waters and other industrial waste waters containing high concentration of organic matter and nitrogen.

• Journal of the Korean Geographical Society
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• v.41 no.2 s.113
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• pp.168-187
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• 2006

Windy meteorological conditions and dried fire fuels due to higher atmospheric instability and dryness in the lower troposphere can exacerbate fire controls and result in more losses of forest resources and residential properties due to enhanced large wildland fires. Long-term (1979-2005) climatology of the Haines Index reconstructed in this study reveals that spatial patterns and intra-annual variability of the atmospheric instability and dryness in the lower troposphere affect the frequency of wildland fire incidences over the Korean Peninsula. Exponential regression models verify that daily high Haines Index and its monthly frequency has statistically significant correlations with the frequency of the wildland fire occurrences during the fire season (December-April) in South Korea. According to the climatic maps of the Haines Index created by the Geographic Information System (GIS) using the Digital Elevation Model (DEM), the lowlands below 500m from the mean sea level in the northwestern regions of the Korean Peninsula demonstrates the high frequency of the Haines Index equal to or greater than five in April and May. The annual frequency of the high Haines Index represents an increasing trend across the Korean Peninsula since the mid-1990s, particularly in Gyeongsangbuk-do and along the eastern coastal areas. The composite of synoptic weather maps at 500hPa for extreme events, in which the high Haines Index lasted for several days consecutively, illustrates that the cold low pressure system developed around the Sea of Okhotsk in the extreme event period enhances the pressure gradient and westerly wind speed over the Korean Peninsula. These results demonstrate the need for further consideration of the spatial-temporal characteristics of vertical atmospheric components, such as atmospheric instability and dryness, in the current Korean fire prediction system.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.6
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• pp.662-671
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• 2015

As the type of Hazardous and Noxious Substances(HNS) becomes various and the transport volume of HNS increases, HNS spill incidents occur frequently on land and the sea. In view of various damages to human lives and properties by HNS spills, it is necessary to educate and train professional personnel in preparation for and response to potential HNS spills. This study shows the current state of response systems and education courses against HNS spill incidents on land and the sea to compare those with each other between land and sea in Korea. Incident command system on land are basically similar to that at sea, but leading authority which is responsible for combating HNS spills at sea is changeable depending on the location of HNS spill, as it were, Korea Coast Guard(KCG) is responsible for urgent response to HNS spill at sea, while municipalities are responsible for the response to HNS drifted ashore. Education courses for HNS responders on land are established at National Fire Service Academy(NFSA), National Institute of Chemical Safety(NICS), etc., and are diverse. Education and training courses for HNS responder at sea are established at Korea Coast Guard Academy(KCGA) and Marine Environment Research & Training Institute(MERTI), and are comparatively simple. Education courses for dangerous cargo handlers who work in port where land is linked to the sea are established at Korea Maritime Dangerous Goods Inspection & Research Institute(KOMDI), Korea Port Training Institute(KPTI) and Korea Institute of Maritime and Fisheries Technology(KIMFT). Through the comparison of education courses for HNS responders between land and sea, some recommendations such as extension of education targets, division of an existing integrated HNS course into two courses composed of operational level and manager level with respective refresh course, on-line cyber course and joint inter-educational institute course in cooperation with other relevant institutes are proposed for the improvement in education courses of KCG and KOEM(Korea Marine Environment Management Corporation) to educate and train professionals for combating HNS spills at sea in Korea.

• The Korean Journal of Air & Space Law and Policy
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• v.1
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• pp.47-85
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• 1989

The Fundamental purpose of the Warsaw Convention was to establish uniform rules applicable to international air transportation. The emphasis on the benefits of uniformity was considered important in the beginning and continues to be important to the present. If the desire for uniformity is indeed the mortar which holds the Warsaw system together then it should be possible to agree on a worldwide liability limit. This liability limit would not be so unreasonable, that it would be impossible for nations to adhere to it. It would preclude any national supplemental compensation plan or Montreal Agreement type of requirement in any jurisdiction. The differentiation of liability limits by national requirement seems to be what is occurring. There is a plethora of mandated limits and Montreal Agreement type 'voluntary' limits. It is becoming difficult to find more than a few major States where an unmodified Warsaw Convention or Hague Protocol limitation is still in effect. If this is the real world in the 1980's, then let the treaty so reflect it. Upon reviewing the Warsaw Convention, its history and the several attempts to amend it, strengths become apparent. Hijackings of international flights have given rise to a number of lawsuits by passengers to recover damages for injuries suffered. This comment is concerned with the liability of an airline for injuries to its passengers resulting from aviation terrorism. In addition, analysis is focused on current airline security measures, particularly the pre-boarding screening system, and the duty of air carriers to prevent weapons from penetrating that system. An airline has a duty to exercise a high degree of care to protect its passengers from the threat of aviation terrorism. This duty would seemingly require the airline to exercise a high degree of care to prevent any passenger from smuggling a weapon or explosive device aboard its aircraft. In the case an unarmed hijacker who boards having no instrument in his possession with which to promote the hoax, a plaintiff-passenger would be hard-pressed to show that the airline was negligent in screening the hijacker prior to boarding. In light of the airline's duty to exercise a high degree of care to provide for the safety of all the passengers on board, an acquiescene to a hijacker's demands on the part of the air carrier could constitute a breach of duty only when it is clearly shown that the carrier's employees knew or plainly should have known that the hijacker was unarmed. A finding of willful misconduct on the part of an air carrier, which is a prerequisite to imposing unlimited liability, remains a question to be determined by a jury using the definition or standard of willful misconduct prevailing in the jurisdiction of the forum court. Through the willful misconduct provision of the Warsaw Convention, air carrier face the possibility of unlimited liability for failure to implement proper preventive precautions against terrorist. Courts, therefore, should broadly construe the willful misconduct provision of the Warsaw Convention in order to find unlimited liability for passenger injuries whenever air carrier security precautions are lacking. In this way, the courts can help ensure air carrier safety and prevention against terrorist attack. Air carriers, therefore, would have an incentive to increase, impose and maintain security precautions designed to thwart such potential terrorist attacks as in the case of Korean Air Lines Flight No.858 incident having a tremendous impact on the civil aviation community. The crash of a commercial airliner, with the attending tragic loss of life and massive destruction of property, always gives rise to shock and indignation. The general opinion is that the legal system could be sufficient, provided that the political will is there to use and apply it effectively. All agreed that the main responsibility for security has to be borne by the governments. I would like to remind all passengers that every discovery of the human spirit may be used for opposite ends; thus, aircraft can be used for air travel but also as targets of terrorism. A state that supports aviation terrorism is responsible for violation of International Aviation Law. Generally speaking, terrorism is a violation of international law. It violates the soverign rights of the states, and the human rights of the individuals. I think that aviation terrorism as becoming an ever more serious issue, has to be solved by internationally agreed and closely co-ordinated measures. We have to contribute more to the creation of a general consensus amongst all states about the need to combat the threat of aviation terrorism.

• 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 East Asian Society of Dietary Life
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• v.24 no.4
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• pp.514-528
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• 2014

This study examined the actual state and future improvement of food allergies in adolescents and adults in order to prevent damage. In this survey, proportions of females, people in their 40s, college graduates, and office workers and housewives with allergies were higher than other groups. Exactly 41.1% of participants responded that they had experienced food allergies while 58.9% responded that they had not. According to their responses, the most common food allergy symptom involved the skin while whole-body allergic reactions were rare. Most respondents answered that frequency of their food allergies was two or three times. There was a variety of allergenic foods, including fast food, eggs, mackerel and milk, and instant food was ranked as the most allergenic food. Therefore, in order to protect consumers from damage caused by food allergens, the food allergen labeling system must be improved. A better food allergen labeling system should be implemented to avoid potential risks of allergic reactions and ensure national food safety.

• The Korean Journal of Air & Space Law and Policy
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• v.32 no.2
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• pp.129-153
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• 2017

Fair Competition policy in aviation field has been discussed since open skies policy began in 1970s. This issue has been also the main topic in the ICAO's Worldwide Air Transport Conference, the Air Transport Symposium, etc. ICAO defines competition as the existent or potential rivalry between two or more operators, carriers or groups, striving for advantages in the same market based on different prices, qualities and services. In a broader sense, the definition includes more various meanings; reasonable, fair, effective, and unrestricted competitions. Nowadays, competition laws and regulations to air transportation have been applied more frequently and the issues varies from antitrust immunity, mergers and alliances, abuse of dominant positions, capacity dumping and predatory pricing, sales and marketing, to airport charges and fees, state aid and loan guarantees. Now, the competition among the airlines or nations in aviation industry is changing to cooperation level. A lot of airlines try to survive by various cooperation methods. Therefore the policy of Korean aviation industry should be developed, taking so-called "the viewpoint of national aviation industry ecosystem" into consideration and Korean government should prepare a policy of fair competition to cope with it. First, in the process of open skies policy with neighboring countries such as China, Japan and the Middle East, it is necessary to apply the fair competition act and prepare laws and regulations to implement it. Second, the standards of effective ownership and control of air transportation business should be reviewed. Third, in preparation for aviation agreements and liberalization, the Korean aviation industry needs to study and review competition and cooperation issues through the analysis of strict aviation market structure for airlines and airport operations. Fourth, it is necessary to create a fair air transportation environment for the development of air transportation and competitiveness through preemptive policies such as the approval of mergers, acquisitions, JV and the ripple effects analysis.