• 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.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1014-1020
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• 1996

To develope a manufacturing process of the Korean type hot sauce, ingredients and chemical components of the imported hot sauces were investigated. The major ingredients of the imported hot sauce were chili, vinegar and salt. Chemical analysis of the imported hot sauce showed: moisture; 44.73-95.66%, total nitrogen; 0.11-1.06%, reducing sugar; 0.03-3.18%, crude fiber; 0.42-2.51%, salt; 0.87-10.44%, pH; 3.22-4.05, titratable acidity; 1.18-3.62%, capsanthin; 0.44-1.06% and capsaicin; 2.40-4.28 mg%. With the red pepper powder and/or kochujang, 20 Korean type hot sauces were prepared. Chemical analysis of the Korean type hot sauce showed: moisture; 53.07-78.30%, total nitrogen; 0.34-0.68%, reducing sugar; 1.60-4.34%, curde fiber; 1.31-2.54%, salt; 4.07-5.56%, pH; 3.37-2.54, titratable acidity; 1.15-3.06%, capsanthin; 0.11-1.36% and capsaicin; 0.55-1.42 mg%. Chemical components except capsaicin of the Korean type hot sauce were similar to those of the imported one. As the results of sensory evaluation on the 20 Korean type hot sauces with red pepper powder and/or kochujang developed, three Korean type hot sauces were finally selected. As compared with Sriracha hot sauce, an imported hot sauce, the Korean type hot sauces were evaluated to be superior to the imported one.

• Journal of the Korean Society of Food Culture
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• v.19 no.2
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• pp.177-183
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• 2004

Green tea, a leaf of the plant Camellia sinensis, is one of the most consumed traditional oriental beverages. Green tea has been considered a medicine and a healthful beverage since ancient times, but recently it has received a great deal of attention because of its antioxidants like polyphenols. Moreover, green tea contains amino acids, carbohydrates, proteins, chlorophyll, volatile compounds, minerals, and phytochemical components that are essential or helpful to human health. Depending on the manufacturing process, green teas are classified into several types. Among these, powdered green tea can be effective in the absorption of ingredients compare with other types of green tea since we take the beverage with powder itself. In this paper, the contents of general ingredients (moisture, proteins, fat, carbohydrates, and ash), minerals (Fe, Mg, Ca, Na, K, and P), hunter color values, and alcohol insoluble substance were determined in total of six powdered green teas commercialized in Korea and Japan.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.06a
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• pp.16-23
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• 2000

The increasing functional needs of top-quality printing papers and packaging paperboards, and especially the rapid developments in electronic printing processes and various computer printers during past few years, set new targets and requirements for modern paper quality. Most of these paper grades of today have relatively high filler content, are moderately or heavily calendered , and have many coating layers for the best appearance and performance. In practice, this means that many of the traditional quality assurance methods, mostly designed to measure papers made of pure. native pulp only, can not reliably (or at all) be used to analyze or rank the quality of modern papers. Hence, introduction of new measurement techniques is necessary to assure and further develop the paper quality today and in the future. Paper formation , i.e. small scale (millimeter scale) variation of basis weight, is the most important quality parameter of paper-making due to its influence on practically all the other quality properties of paper. The ideal paper would be completely uniform so that the basis weight of each small point (area) measured would be the same. In practice, of course, this is not possible because there always exists relatively large local variations in paper. However, these small scale basis weight variations are the major reason for many other quality problems, including calender blacking uneven coating result, uneven printing result, etc. The traditionally used visual inspection or optical measurement of the paper does not give us a reliable understanding of the material variations in the paper because in modern paper making process the optical behavior of paper is strongly affected by using e.g. fillers, dye or coating colors. Futhermore, the opacity (optical density) of the paper is changed at different process stages like wet pressing and calendering. The greatest advantage of using beta transmission method to measure paper formation is that it can be very reliably calibrated to measure true basis weight variation of all kinds of paper and board, independently on sample basis weight or paper grade. This gives us the possibility to measure, compare and judge papers made of different raw materials, different color, or even to measure heavily calendered, coated or printed papers. Scientific research of paper physics has shown that the orientation of the top layer (paper surface) fibers of the sheet paly the key role in paper curling and cockling , causing the typical practical problems (paper jam) with modern fax and copy machines, electronic printing , etc. On the other hand, the fiber orientation at the surface and middle layer of the sheet controls the bending stiffness of paperboard . Therefore, a reliable measurement of paper surface fiber orientation gives us a magnificent tool to investigate and predict paper curling and coclking tendency, and provides the necessary information to finetune, the manufacturing process for optimum quality. many papers, especially heavily calendered and coated grades, do resist liquid and gas penetration very much, bing beyond the measurement range of the traditional instruments or resulting invonveniently long measuring time per sample . The increased surface hardness and use of filler minerals and mechanical pulp make a reliable, nonleaking sample contact to the measurement head a challenge of its own. Paper surface coating causes, as expected, a layer which has completely different permeability characteristics compared to the other layer of the sheet. The latest developments in sensor technologies have made it possible to reliably measure gas flow in well controlled conditions, allowing us to investigate the gas penetration of open structures, such as cigarette paper, tissue or sack paper, and in the low permeability range analyze even fully greaseproof papers, silicon papers, heavily coated papers and boards or even detect defects in barrier coatings ! Even nitrogen or helium may be used as the gas, giving us completely new possibilities to rank the products or to find correlation to critical process or converting parameters. All the modern paper machines include many on-line measuring instruments which are used to give the necessary information for automatic process control systems. hence, the reliability of this information obtained from different sensors is vital for good optimizing and process stability. If any of these on-line sensors do not operate perfectly ass planned (having even small measurement error or malfunction ), the process control will set the machine to operate away from the optimum , resulting loss of profit or eventual problems in quality or runnability. To assure optimum operation of the paper machines, a novel quality assurance policy for the on-line measurements has been developed, including control procedures utilizing traceable, accredited standards for the best reliability and performance.

• Journal of Animal Environmental Science
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• v.13 no.3
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• pp.211-218
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• 2007

This study was carried out to develop the technique for manufacturing activated carbon from livestock manure and to analyse it's odor absorptiveness. Each of layer manure(LM), litter from broiler house(BL) and litter from dairy barn(DL), compost from layer manure(LC) and pig manure(PC), and coconut shell(CS) was used as a raw material. Activated carbon by grinding the raw material, adding the coal tar as a binder, palletizing, drying, heating with $N_2$ gas at $400^{\circ}C$ for 1 hour, activating by reaction with steam at a temperature of $750^{\circ}C$ for 1 hour. Moisture contents of raw material was 44.9% in layer compost, 71.9% in layer manure, 24.4% in broiler litter, 47% in pig manure compost and 33.9% in dairy litter. Volatile matter in layer compost, layer manure, broiler litter, pig manure compost and dairy litter was 18.8%, 31.0%, 49.8%, 22.3% and 11.6%, respectively. Surface area(BET) of activated carbon from layer compost, layer manure, broiler litter, pig manure compost, dairy litter and coconut shell was 259.8, 209.8, 63.5, 442.3, 812.9 and $1,040\;m^2/g$, respectively. Activated carbon made by livestock manure or litter were examined with scanning electron microscope, and micropore was a type of sponge like particles honeycombed with chambers. Pore size of activated carbon was ranged from 0.39 to $5.02\;{\AA}$, but coconut shell was $0.30\;{\AA}$. Iodine absorptiveness of activated carbon from livestock manure was $530{\sim}580mg/g$. But activated carbon made by coconut shell was 1000 mg/g. Each activated carbon could absorb odor compound very well. Absorptiveness of activated carbon from layer manure for hydrogen sulfide and trimethyl amino was 74.5% and 73.9% at the accumulated flux of 60,000 ml, but, in the case of ammonia was only 15.2% at the accumulated flux of 10,000 ml

• Journal of Yeungnam Medical Science
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• v.7 no.1
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• pp.81-93
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• 1990

The author fractographically analyized the cause of metal failure(the first time this procedure has been used for this metal failure)and also analyized it clinically. In this study, I selected eight cases which have been analyized fractographically. In all these cases, the analysis was done after treatment of metal failure of implants internally fixed to femur shaft fractures at the Department of Orthopedic Surgery, Yeung-Nam University Hospital during the six year period from May 1983 to September 1989. 1. Metal failure occured in five dynamic-compression plates, one Jewett nail, one screw in Rowe plate, and one interlocking nail. 2. The clinical cause of metal failure was deficiency of medial butress in five cases, incorrect position of implant in one case, and incorrect selection of implant in two cases. 3. The time interval between internal fixation and metal failure was four months in one case, between five months to twelve months in six cases, three years in one case. 4. The fractographically analytical cause of metal failure was ; first, impact failure, one case, second, fatigue failure, six cases, machining mark(stress liser), four cases type : low consistent cyclic fatigue failure irregular cyclic fatigue failure third, stress corrosion crack, one case. 5. 316L Stainless Steel has good resistance to corrosion. However, when its peculiar surface film is destroyed by fretting, it shows pitting corrosion. This is, perhaps, the main cause of metal failure. 6. It is possible that mechanical injury occured in implants during the manufacturing of implants or that making a screw hole is the main cause of metal failure.

• Journal of Mushroom
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• v.18 no.4
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• pp.357-364
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• 2020

The grade and price of Lentinula edodes largely differs in preference depending on the product area and seasonal factors. The product amount of autumn L. edodes was higher than that of spring L. edodes, but high quality, which is divided into "Hwago" is low in preference. Mostly, the autumn L. edodes is obtained as powder; hence, it is necessary to develop a processing method to utilize its flavor and aroma at an affordable price. Additionally, we estimated the content of 𝛽-glucan, ergosterol, vitamin D₂, reducing sugars, and free amino acids and evaluated the anti-inflammatory activity of saccharification powder of log-cultivated L. edodes. In the saccharification powders obtained via 7 min of UV irradiation of log-cultivated L. edodes, 𝛽-glucan and vitamin D₂ contents were found to be the highest, whereas ergosterol content was found to be the lowest. The content of reducing sugars ranged from 62.4 mg/L to 68.2 mg/L. The free amino acids were higher in these saccharification powders than in the control. Subsequently, RAW 264.7 cells were treated with different concentrations (10, 50, 100, 200, 300, and 500 ㎍/mL) of the saccharification powders of log-cultivated L. edodes obtained via different UV irradiation time applications. The cells showed good viability; the anti-inflammatory effect was found to be the highest at 7 min UV irradiation. Therefore, 7 min of UV irradiation was determined to be the optimum condition for manufacturing saccharification powders of log-cultivated L. edodes. Hence, saccharification powders of log-cultivated L. edodes may be used as a raw material for natural sweeteners, food additives, and in the food industry.

• Korean Journal of Heritage: History & Science
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• v.55 no.4
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• pp.138-164
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• 2022

The Neolithic shell midden in Daejuk-ri, Seosan, is distributed on the gentle slope of a low hill close to the west coast. The bedrock of the area consists mainly of schist with various mafic minerals, but shows a partial gneiss pattern. The site consists of loamy topsoil and clay loam subsoil, and the degree of siallization is relatively low. Although the pottery excavated from the shell midden shares mostly similar features, a variety of shapes and patterns coexist. The surface colors, thickness and physical properties are slightly different. The pottery can be subdivided into three types (IA, IB and II) according to the composition of the body clay, the temper and the existence of a black core. Types IA and IB are colorless mineral pottery with a non-black or black core respectively. TypeII is colored mineral pottery with a non-black core. Type I pottery also contains non-plastic colored minerals, but type II contains a large amount of biotite, chlorite, talc, amphibole, diopside and tremolite, which include a large amount of Mg and Fe. The studied pottery contains a small amount of organic matter. Considering the grain size and relatively poor sorting and roundness of the non-plastic particles, the pottery appears to be made by adding coarse non-plastic tempers for special purposes to the untreated weathered soil around the site. The three types of pottery seem to have been incompletely fired in general. While type IB has the lowest degree of oxidation, typeII shows the highest degree of redness and oxidation. It can be interpreted that these differences depend on the firing temperature and the ratio of non-plastic particles. Through a synthesis of the minerals, geochemical data and thermal history, it can be determined that the firing temperature ranged from 600 to 700℃. The pottery types of the Daejuk-ri Shell Midden have slightly different production conditions, mineral compositions, and physical properties, but have undergone similar production processes with basically the same clay materials. The clay is almost identical to the composition of the bedrock and weathered soil distributed in the Daejuk-ri area. Currently, there is an industrial complex in the area, so it is difficult to confirm the soil and geological distribution of the site. However, it is highly probable that the area around the site was self-sufficient for the clay and tempers required for the production of the Neolithic pottery. Therefore, it can be interpreted that the group that left the shell midden in Daejuk-ri lived near the site, visited the site for the purpose of collecting and processing shellfish, and discarded the broken pottery along with shells.

• Journal of Communication Design
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• v.66
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• pp.90-101
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• 2019

South Korea had a hard time creating its own image of a nation that formed its identity due to 6.25, Japanese-style rule, division of South and North Korea, and military dictatorship. Recently, Korea has been searching and spreading its identity by creating a Korean wave such as various events and K-POPs. However, since there are still no images and cultural products representing Korea's identity, it is necessary to develop design contents related to native culture and professional cultural product design. Design powers such as France and Japan focus on design projects that can add value to their national design policy projects. Traditional Korean contents also need to be specialized and continuous in image design and research. In this study, five lucky-SubokGangnYeon(long life, happiness and peace), a representative of Korean culture, studied with the most interest in the old and the modern, namely, "Living healthy long." Through the development of cultural product design and the use of design content, I would look forward to presenting the diversity and direction in producing Korea's own design products and images that fit the trend of modern 'age of 100.' Based on images based on special exhibitions related to longevity of the National Folk Museum of Korea, the museum discovers key used features and meanings, studies patterns and patterns, and analyzes design cases applied to modern cultural product design. We also want to look at the direction available through design content, which is a symbol of llong life happiness and peace. First, cultural products have limitations that lack the development of design products, lack of public relations and sales outlets, and lack of awareness of traditional culture, which should precede policy support and awareness reform at the national level. Second, we need to streamline prices that meet the needs of the market. Third, cultural product design and contents related to tradition can be settled and disseminated more easily when traditional design is utilized and distributed mainly on practical stationery and household goods. Fourth, it is necessary to develop contents of various Korean images based on research on Korean cultural history and aesthetic consciousness. Research on the Korean culture of designers should be conducted, not just in the form of figurative images. Fifth, traditional manufacturing methods and materials should be respected by modern times, but modern production products should be developed with economy and durability.

• Journal of Venture Innovation
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• v.3 no.2
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• pp.41-76
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• 2020

This study confirmed factors affecting smart factory technology acceptance through empirical analysis. It is a study on what factors have an important influence on the introduction of the smart factory, which is the core field of the 4th industry. I believe that there is academic and practical significance in the context of insufficient research on technology acceptance in the field of smart factories. This research was conducted based on the Unified Theory of Acceptance and Use of Technology (UTAUT), whose explanatory power has been proven in the study of the acceptance factors of information technology. In addition to the four independent variables of the UTAUT : Performance Expectancy, Effort Expectancy, Social Influence, and Facilitating Conditions, Government Assistance Expectancy, which is expected to be an important factor due to the characteristics of the smart factory, was added to the independent variable. And, in order to confirm the technical factors of smart factory technology acceptance, the Task Technology Fit(TTF) was added to empirically analyze the effect on Behavioral Intention. Trust is added as a parameter because the degree of trust in new technologies is expected to have a very important effect on the acceptance of technologies. Finally, empirical verification was conducted by adding Innovation Resistance to a research variable that plays a role as a moderator, based on previous studies that innovation by new information technology can inevitably cause refusal to users. For empirical analysis, an online questionnaire of random sampling method was conducted for incumbents of domestic small and medium-sized enterprises, and 309 copies of effective responses were used for empirical analysis. Amos 23.0 and Process macro 3.4 were used for statistical analysis. For accurate statistical analysis, the validity of Research Model and Measurement Variable were secured through confirmatory factor analysis. Accurate empirical analysis was conducted through appropriate statistical procedures and correct interpretation for causality verification, mediating effect verification, and moderating effect verification. Performance Expectancy, Social Influence, Government Assistance Expectancy, and Task Technology Fit had a positive (+) effect on smart factory technology acceptance. The magnitude of influence was found in the order of Government Assistance Expectancy(β=.487) > Task Technology Fit(β=.218) > Performance Expectancy(β=.205) > Social Influence(β=.204). Both the Task Characteristics and the Technology Characteristics were confirmed to have a positive (+) effect on Task Technology Fit. It was found that Task Characteristics(β=.559) had a greater effect on Task Technology Fit than Technology Characteristics(β=.328). In the mediating effect verification on Trust, a statistically significant mediating role of Trust was not identified between each of the six independent variables and the intention to introduce a smart factory. Through the verification of the moderating effect of Innovation Resistance, it was found that Innovation Resistance plays a positive (+) moderating role between Government Assistance Expectancy, and technology acceptance intention. In other words, the greater the Innovation Resistance, the greater the influence of the Government Assistance Expectancy on the intention to adopt the smart factory than the case where there is less Innovation Resistance. Based on this, academic and practical implications were presented.