• Nuclear Engineering and Technology
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• v.39 no.5
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• pp.603-616
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• 2007

Roy Huddle, having invented the coated particle in Harwell 1957, stated in the early 1970s that we know now everything about particles and coatings and should be going over to deal with other problems. This was on the occasion of the Dragon fuel performance information meeting London 1973: How wrong a genius be! It took until 1978 that really good particles were made in Germany, then during the Japanese HTTR production in the 1990s and finally the Chinese 2000-2001 campaign for HTR-10. Here, we present a review of history and present status. Today, good fuel is measured by different standards from the seventies: where $9*10^{-4}$ initial free heavy metal fraction was typical for early AVR carbide fuel and $3*10^{-4}$ initial free heavy metal fraction was acceptable for oxide fuel in THTR, we insist on values more than an order of magnitude below this value today. Half a percent of particle failure at the end-of-irradiation, another ancient standard, is not even acceptable today, even for the most severe accidents. While legislation and licensing has not changed, one of the reasons we insist on these improvements is the preference for passive systems rather than active controls of earlier times. After renewed HTGR interest, we are reporting about the start of new or reactivated coated particle work in several parts of the world, considering the aspects of designs/ traditional and new materials, manufacturing technologies/ quality control quality assurance, irradiation and accident performance, modeling and performance predictions, and fuel cycle aspects and spent fuel treatment. In very general terms, the coated particle should be strong, reliable, retentive, and affordable. These properties have to be quantified and will be eventually optimized for a specific application system. Results obtained so far indicate that the same particle can be used for steam cycle applications with $700-750^{\circ}C$ helium coolant gas exit, for gas turbine applications at $850-900^{\circ}C$ and for process heat/hydrogen generation applications with $950^{\circ}C$ outlet temperatures. There is a clear set of standards for modem high quality fuel in terms of low levels of heavy metal contamination, manufacture-induced particle defects during fuel body and fuel element making, irradiation/accident induced particle failures and limits on fission product release from intact particles. While gas-cooled reactor design is still open-ended with blocks for the prismatic and spherical fuel elements for the pebble-bed design, there is near worldwide agreement on high quality fuel: a $500{\mu}m$ diameter $UO_2$ kernel of 10% enrichment is surrounded by a $100{\mu}m$ thick sacrificial buffer layer to be followed by a dense inner pyrocarbon layer, a high quality silicon carbide layer of $35{\mu}m$ thickness and theoretical density and another outer pyrocarbon layer. Good performance has been demonstrated both under operational and under accident conditions, i.e. to 10% FIMA and maximum $1600^{\circ}C$ afterwards. And it is the wide-ranging demonstration experience that makes this particle superior. Recommendations are made for further work: 1. Generation of data for presently manufactured materials, e.g. SiC strength and strength distribution, PyC creep and shrinkage and many more material data sets. 2. Renewed start of irradiation and accident testing of modem coated particle fuel. 3. Analysis of existing and newly created data with a view to demonstrate satisfactory performance at burnups beyond 10% FIMA and complete fission product retention even in accidents that go beyond $1600^{\circ}C$ for a short period of time. This work should proceed at both national and international level.

• Food Science and Preservation
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• v.24 no.8
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• pp.1094-1102
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• 2017

Hazardous metals leaching experiment was carried out in accordance with various usage environments for camping cooking utensils distributed in the market. There was a significant difference in the degree of migration for lead, arsenic, cadmium and nickel defending on the solvent and how to use, although they were all appropriate for criteria. In general, the migrated amount of aluminum was increased in acidic condition, and the migrated amount of arsenic was increased in salty condition. Physical scratches increased the overall release of hazardous metals from the portable pots and pans for camping in all solvents. Especially, in 0.5% citric acid solution, cadmium was migrated by physical scratch in stainless steel and hard aluminum pots and pans. The longer the leaching time, the higher the migration of aluminum in acid condition and arsenic in basic condition. From these results, it is desirable to use the cooking utensil for camping without being exposed to strong acidic or basic solution and scratches in order to reduce the migration of hazardous metals from them.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.3
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• pp.183-192
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• 1982

The variability of rice productivity during last 2 decades (1961-1980) of ten years before and after the introduction of"Tongil" was reviewed from the epochal, regional and varietal points of view. During that period the cultivated area of paddy rice have remained almost unchanged, while the total rice production have got elevated from 3, 463 million metric tons in 1961 to 6.006 million metric tons in 1977, recording 73.4% increase. This remarkable increase in rice production is considered to be attributable much to the development and release of new high yielding variety, "Tongil", coupled with the amelioration of cultural techniques. However, in 1978 Tongil type varieties experienced the epidemic outbreak of blast disease due to the shifted race population of blast fungus and in 1980 recorded poor rice production as low as in 1960's due to the unfavorable weather stress throughout the rice growing season, giving rise to many problems awaiting solutions for securing the stabilized high production of rice. The rice yield has continued the gradual increase during last two decades but its difference between farmer and research organization have got wider from 79kg/10a during 1960 to 1971 to 101kg/l0a during 1972 to 1980, and also the inter-regional differences have been increased from 50-60kg/10a to 80kg/10a during those periods. Therefore, this proves that we have raised the upper boundary of rice yield by increasing the yield potential of rice variety but have not changed those absolute deviations. Estimates indicate that the increased rice production during that period was indebted 40 percent to the varietal improvement and 13 percent to the ameliorated agro-technologies, and the rest, 47 percent, could be ascribed to the other factors besides varieties and cultural technologies such as the improved agricultural environments, etc. Of course, even though it cannot be expected to unify the cultural environments and the cultural technologies, provided that much efforts are to be endeavored to minimize the yield difference of 20 percent between farmer and research organizations and the inter-regional yield difference of 20 percent, much increased rice production can be expected to be achieved with the current level of cultural technology and the yielding potential of the present rice varieties. In order to expedite the above effects on rice production the followings are to be put into practices consitently and steadfastly. 1. Reinforcement of breeding for varieties with high yielding potential and less susceptible to climatic-stress and pests, and of basic physicoecological studies of rice plant for improving the cultural technologies. 2. Continuous endeavor to secure the stabilized cultural environments by improving the soil fertility and increasing the drainage and irrigation facilities. 3. Political back-up to encourage the farmers' incentives for production 4. Precise surveys for agricultural statistics to facilitate the long-term planninge long-term planning.

• Journal of Soil and Groundwater Environment
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• v.11 no.5
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• pp.20-34
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• 2006

This study was undertaken to assess the anthropogenic impact on trace metal concentrations (Zn, Cu, Pb, Cr, Ni, and Cd) of roadside sediments (N = 70) from No.7 national road within the watershed of Hoidong Reservoir in Pusan City and to estimate the potential mobility of selected metals using sequential extraction. We generally found high concentrations of metals, especially Zn, Cu and Pb, affected by anthropogenic inputs. Compared to the trace metal concentrations of uncontaminated stream sediments, arithmetic mean concentrations of roadside sediments were about 7 times higher for Cu, 4 times higher for Zn, 3 times higher for Pb and Cr and, 2 times higher for Ni and As. Speciation data on the basis of sequential extraction indicate that most of the trace metals considered do not occur in significant quantities in the exchangeable fraction, except for Cd and Ni whose exchangeable fractions are appreciable (average 29.3 and 25.8%, respectively). Other metals such as Zn (51.4%) and Pb (45.2%) are preferentially bound to the reducible fraction, and therefore they can be potentially released by a pH decrease and/or redox change. Copper is mainly found in the organic fraction, while Cd is highest in the exchangeable fraction, and Cr and Ni in the residual fraction. Considering the proportion of metals bound to the exchangeable and carbonate fractions, the comparative mobility of metals probably decreases in the order of Cd>Ni>Pb>Zn>Cr>Cu. Although the total concentration data showed that Zn was typically present in potentially harmful concentration levels, the data on metal partitioning indicated that Cd, Ni and Pb pose the highest potential hazard for runoff water. As potential changes of redox state and pH may remobilize the metals bound to carbonates, amorphous oxides, and/or organic matter, and may release and flush them through drain networks into the watershed of Hoidong Reservoir, careful monitoring of environmental conditions appears to be very important.

• 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 Legislation Research
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• no.44
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• pp.611-653
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• 2013

An whistle-blowing is recognition of acts of misconduct or corruption by individuals(laborers) or party which belongs to a certain organization and it refers to the act of informing to the senior organization or to the outside public agency to avoid jeopardies that could be potentially lead against benefit of the public. These whistle-blowings can be a Ansatz that improve corporation's transparency and accountability by prevention of enterprise's misconduct as well, it has been recognized as an important role for the establishment of corporate ethics, moreover, social justice. What to be treated primarily as labor law problem is arousing some controversies of the possibility that the public announcement could be whether a disciplinary punishment or not because it brings some mischievous effects for the honor and the reputation to the company which conducted the illegal actions and the action of the contrary to the social value. And futhermore, recently, the matter of compensational responsibility according to the arrangement conversion, bullying followed by the informant has been brought up. The fundamental standpoint of precedent related with the judgement of justification for the punishment as reason of the whistle-blowing ought to do the sincere duty for the labor contract which is the employees are supposed to consider the employer's profits. For that reason, if the emploee release the inside fact to the public and give any damages to employer's secret or confidence or honor, it will be a causing reasong of the disciplinary punishment, but in specific cases, the relevant and level of punishment limitation can be judged by the contents of public announcement and the truth, the purpose of the acts and details and the way of announcement. Precisely, on the assumption that there are necessity of the characteristic profit or the freedom of expression for the informant, with overall consideration whether or the basis part of the informant is true or there is a fair reason which make the informant believe is true or the purpose of informant has the public profit or the contents of the whistle-blowing are important for relevant organization or the means and the way was suitable, if the whistle-blowing are approved to be resonable, the organization are not permitted the reprimand or dismiss Futhermore, to find the solution for the issues of the disciplinary punishment and the treatment of all sorts of disadvantages, for the reason of whistle-blowing, since the protection law for public declarer which was enacted in last 2011 have the position as the general law, the purport of the equal law has to be considered sytematically and also the judicial precedent which is related to the justification of whistle-blowing are needed to be considered as well.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.15 no.2
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• pp.169-182
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• 2002

Background: Allergic rhinitis(AR) is a heterogeneous disorder that despite its high prevalence is often undiagnosed. It is characterized by one or more symptoms including sneezing, itching, nasal congestion, and rhinorrhea. And it is frequently accompanied by symptoms involving the eyes, ears, and throat, including postnasal drainage. There are many different causes of rhinitis in children and adults. Approximately 50$\%$ of all cases of rhinitis are caused by allergy. In the case of rhinitis caused by allergens, symptoms arise as a result of inflammation induced by a gamma globulin E-mediated immune response to specific allergens such as pollens, molds, animal dander, and dust mites. The immune response involves the release of inflammatory mediators and the activation and recruitment of cells to the nasal mucosa. AR is similar to 鼻？, hypersensitive rhinitis in Oriental Medicine. I think hypersensitive rhinitis is including of AR, vasomotor rhinitis and non-allergic rhinitis related with eosinophil increased and so on. Purpose: To perform a clinical analysis of hypersensitive rhinitis including allergic rhinitis and estimate the efficacy of Oriental Medical treatment. Objective: We studied 96 patients who had visited our hospital with complaints of nasal symptoms from March 2000 to February 2002; they had the signs more than 2 - nasal obstruction, watery discharge, sneezing and eye or nasal itching. Parameters Observed & Methods: We treated them with acupuncture & herb-medication. Sometime they used aroma oil or external medicine. 1) the distribution of sex & age groups 2) the clinical type based on duration & the severity of symptom 3) the breakdown of complication & pasl history of Otolaryngologic or allergic disease 4) the clinical assessment and classification of rhinitis(sneezers and runners & blockers) 5) the associated symptoms and signs 6) the classification of Byeonjeung 7) the classification of prescriptions and 8) the efficacy of treatment. Result: 1. In the clinical type of based on duration, the intermittent type was 42.7$\%$ and the persistent was 57.3$\%$. 2. We observed the severity of symptoms based on the quality of life. The mild type was 24.0$\%$ and the moderate-severe was 76.0$\%$. 3. In the clinical assessment and classification of rhinitis, the sneezers and runners type was 69.8$\%$ and the blockers was 30.2$\%$. 4. The most common family history with otolaryngologic or allergic disease were allergic rhinitis(17.7$\%$), urticaria, paranasal sinusitis and T.B.(3.1$\%$). 5. The most common past history with otolaryngologic or allergic disease were paranasal sinusitis(14.6$\%$), atopic dermatitis and asthma(8.3$\%$). It was 31.3$\%$ they had a family history and 44.8$\%$, past history. 6. The most common complication was paranasal sinusitis(15.6$\%$). In decreasing order the others were otitis media with effusion(9.4$\%$), GERD and headache(6.3$\%$), asthma, bronchitis, nasal bleeding and allergic dermatitis(5.2$\%$). 7. Classification through Byeonjeung : ⅰ) 39 cases(34.9$\%$) were classified as showing Deficiency syndrome. The insuffficiency of Qi was 17.7$\%$, deficiency of Kidney-Yang, 12.5$\%$ and Lung-Cold, 10.4$\%$. ⅱ) 57 cases(59.4$\%$) were classified as showing Excess syndrome. The Fever of YangMing-meridian was 35.4$\%$, Lung-Fever, 24.0$\%$. 8. The efficacy of treatments showed: an improvement in 22cases(22.9$\%$); an improvement partly in 24 cases(25.0$\%$); no real improvement or changes in 16 cases(16.7$\%$); and couldn't check the results 18cases(18.6$\%$). Conclusion: We suggest that this study could be utilized as a standard of clinical Oriental Medical treatment when we treat hypersensitive rhinitis including allergic rhinitis.

• The Korean Journal of Blood Transfusion
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• v.29 no.3
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• pp.262-272
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• 2018

Background: Massive hemorrhage due to trauma is one of the major causes of death in trauma patients, and the quick supply of appropriate blood products is critical in order to reduce the mortality rate. We introduced a massive transfusion protocol (MTP) for safe and rapid transfusion of trauma patients. Using records collected since its adoption, we compared the characteristics of MTP applied group (MTP group) and MTP not applied group (non-MTP group) to determine whether there is an indicator for predicting patients to be treated with MTP. Methods: We retrospectively reviewed the electronic medical records and laboratory findings of patients who received massive transfusions in the trauma emergency room of a single tertiary hospital from February to August 2018. We analyzed various laboratory test results, the amount and ratio of the transfused blood products, and the time required for blood products to be released for the MTP group and the non-MTP group. Results: Of the 54 trauma patients who received massive transfusions, 31 were in the MTP group and 22 in the non-MTP group. There was no significant difference in initial vital signs (except blood pressure) and laboratory test results. Also there was no difference in the amount and ratio of blood products, but the time required for blood product release was shorter in the MTP group. Conclusion: There was no significant difference in clinical findings such as initial vital signs and laboratory test results between the MTP and non-MTP groups, but required blood products were prepared and released more quickly for the MTP group.

• Journal of Korea Entertainment Industry Association
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• v.14 no.3
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• pp.191-200
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• 2020

Companies are seeking to maximize profits through exports and imports in the ultra-fast, ultra-high-speed modern society. It is only possible to sustain its survival if it targets the global market, not based on any specific region. The K-POP group is also targeting overseas markets in a manner similar to the various global strategies used when companies make inroads into foreign markets, including exports, contracts and direct investment. The K-POP group is engaged in various forms of activities, ranging from simple forms of performance (export) that are visited and staged by an invitation from a certain foreign country to series performances (license) by an invitation from a local promoter and tour performances using its capabilities. The K-POP group is seeking to go beyond the art of single-stage performances and make a systematic plan and make inroads into foreign countries in the form of direct investment suitable for each foreign country. The K-POP group made inroads into overseas markets in the form of simple performances from the late 1990s to 2005, when 'Korean Wave' was first introduced. Group H.O.T., etc. are typical examples. Since then, it has sought to enter overseas markets in the form of franchises by accepting overseas members by 2018, starting with Super Junior in 2005. Since then, the K-POP group in the form of joint investment attempted as group IZ*ONE in 2018 appeared, and a voice story came out in September 2018 when South Korea's JYP Entertainment and Tencent of China joined forces. Unlike K-POP Group, which has entered foreign markets with a global strategy based on the existing export method (H.O.T.), 'Boystory' is a representative group that is made with joint investment, which is a direct investment method. In February 2020, RBW released 'D1Verse,' a five-member group selected by Vietnam's reality show, as a joint investment-type group. This shows the possibility that domestic and foreign companies will release a group in the form of joint investment in order to pursue both globalization and localization.

• Journal of Practical Agriculture & Fisheries Research
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• v.25 no.3
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• pp.19-29
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• 2023

This study investigated effect of water temperature change on the formation and release of conchospores of Neopyropia yezoensis. We observed that conchocelis growth and conchospores formation in oyster shell at labolatory during 7 weeks. In order to investigate the amount of conchospore formation in oyster shells, which was being cultured at 28℃, was moved to 10℃, 18℃, 28℃, and culture during 6 weeks. At 10℃, we observed an average of 127 for 1 week, 127 for 2 weeks, 95 for 3 weeks, 90 for 4 weeks, 76 for 5 weeks, and 75 for 6 weeks. At 18℃, we observed an average of 141 for 1 week, 135 for 2 weeks, 94 for 3 weeks, 153 for 4 weeks, 162 for 5 weeks, and 2 for 6 weeks. At 28℃, we observed an average of 167 for 1 week, 102 for 2 weeks, 148 for 3 weeks, 157 for 4 weeks, 270 for 5 weeks, and 138 for 6 weeks. Conchospores released from the shell grew into a young thalli in the culture for 6 weeks, and the number of ones was counted. The number of young thalli were investigated at 10℃, 0 for 1 week, 189 for 2 weeks, 200 for 3 weeks, 89 for 4 weeks, 56 for 5 weeks and 27 for 6 weeks. At 18℃, It observed 0 for 1 week, 26 for 2 weeks, 546 for 3 weeks, 16 for 4 weeks, 17 for 5 weeks and 154 for 6 weeks. It was not observed at 28℃.