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Evaluation of the Potential of Nitrogen Plasma to Cosmetics (질소 플라즈마의 화장품 가능성 평가)

  • Lee, So Min;Jung, So Young;Brito, Sofia;Heo, Hyojin;Cha, Byungsun;Lei, Lei;Lee, Sang Hun;Lee, Mi-Gi;Bin, Bum-Ho;Kwak, Byeong-Mun
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.48 no.3
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    • pp.189-196
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    • 2022
  • Plasma refers to an ionized gas that is often referred to as "the fourth phase of matter", following solid, liquid, and gas. Plasma has traditionally been utilized for industrial applications such as welding and neon signs, but its promise in biomedical fields such as cancer treatment and dermatology has lately been recognized. Indeed, due to its beneficial effects in promoting collagen production, improving skin tone, and eliminating harmful bacteria in the skin, plasma treatment constitutes an important target for dermatological research. In this study, a plasma device for cosmetic manufacturing based on nitrogen, the main component of the atmosphere, was designed and assembled. Moreover, nitric oxide (NO) was selected since is easier to follow and evaluate than other nitrogen plasma active species, and its contents were measured to perform a quantitative and qualitative evaluation of plasma. First, an injection method, using different proximities labeled "sinking" and "non sinking" treatments, was performed to test the most efficient plasma treatment method. As a result, it was observed that the formulation obtained by a non sinking treatment was more effective. Furthermore, toner and ampoule were selected as cosmetics formulations, and the characteristics of the formulation and changes in the injected plasma state were observed. In both formulations, the successful injection of NO plasma was 2 times higher in toner formulation than ampoule formulation, and it gradually decreased with time, having dissipated after a week. It was confirmed that the nitrogen plasma used did not affect the stability of the toner and ampoule formulations at low temperature (4 ℃), room temperature (25 ℃), and high temperature (37 ℃ and 50 ℃) conditions. The results of this study demonstrate the potential of plasma cosmetics and highlight the importance of securing the stability of the injected plasma.

A Review on the Recycling of the Concrete Waste Generate from the Decommissioning of Nuclear Power Plants (원전 해체 콘크리트 폐기물의 재활용에 대한 고찰)

  • Jeon, Ji-Hun;Lee, Woo-Chun;Lee, Sang-Woo;Kim, Soon-Oh
    • Economic and Environmental Geology
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    • v.54 no.2
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    • pp.285-297
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    • 2021
  • Globally, nuclear-decommissioning facilities have been increased in number, and thereby hundreds of thousands of wastes, such as concrete, soil, and metal, have been generated. For this reason, there have been numerous efforts and researches on the development of technology for volume reduction and recycling of solid radioactive wastes, and this study reviewed and examined thoroughly such previous studies. The waste concrete powder is rehydrated by other processes such as grinding and sintering, and the processes rendered aluminate (C3A), C4AF, C3S, and ��-C2S, which are the significant compounds controlling the hydration reaction of concrete and the compressive strength of the solidified matrix. The review of the previous studies confirmed that waste concretes could be used as recycling cement, but there remain problems with the decreasing strength of solidified matrix due to mingling with aggregates. There have been further efforts to improve the performance of recycling concrete via mixing with reactive agents using industrial by-products, such as blast furnace slag and fly ash. As a result, the compressive strength of the solidified matrix was proved to be enhanced. On the contrary, there have been few kinds of researches on manufacturing recycled concretes using soil wastes. Illite and zeolite in soil waste show the high adsorption capacity on radioactive nuclides, and they can be recycled as solidification agents. If the soil wastes are recycled as much as possible, the volume of wastes generated from the decommissioning of nuclear power plants (NPPs) is not only significantly reduced, but collateral benefits also are received because radioactive wastes are safely disposed of by solidification agents made from such soil wastes. Thus, it is required to study the production of non-sintered cement using clay minerals in soil wastes. This paper reviewed related domestic and foreign researches to consider the sustainable recycling of concrete waste from NPPs as recycling cement and utilizing clay minerals in soil waste to produce unsintered cement.

A Study on the Resource Recovery of Fe-Clinker generated in the Recycling Process of Electric Arc Furnace Dust (전기로 제강분진의 재활용과정에서 발생되는 Fe-Clinker의 자원화에 관한 연구)

  • Jae-hong Yoon;Chi-hyun Yoon;Hirofumi Sugimoto;Akio Honjo
    • Resources Recycling
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    • v.32 no.1
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    • pp.50-59
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    • 2023
  • The amount of dust generated during the dissolution of scrap in an electric arc furnace is approximately 1.5% of the scrap metal input, and it is primarily collected in a bag filter. Electric arc furnace dust primarily consists of zinc and ion. The processing of zinc starts with its conversion into pellet form by the addition of a carbon-based reducing agent(coke, anthracite) and limestone (C/S control). These pellets then undergo reduction, volatilization, and re-oxidation in rotary kiln or RHF reactor to recover crude zinc oxide (60%w/w). Next, iron is discharged from the electric arc furnace dust as a solid called Fe clinker (secondary by-product of the Fe-base). Several methods are then used to treat the Fe clinker, which vary depending on the country, including landfilling and recycling (e.g., subbase course material, aggregate for concrete, Fe-source for cement manufacturing). However, landfilling has several drawbacks, including environmental pollution due to leaching, high landfill costs, and wastage of iron resources. To improve Fe recovery in the clinker, we pulverized it into optimal -sized particles and employed specific gravity and magnetic force selection methods to isolate this metal. A carbon-based reducing agent and a binding material were added to the separated coarse powder (>10㎛) to prepare briquette clinker. A small amount (1-3%w/w) of the briquette clinker was charged with the scrap in an electric arc furnace to evaluate its feasibility as an additives (carbonaceous material, heat-generating material, and Fe source).

Simultaneous determinations of anthracycline antibiotics by high performance liquid chromatography coupled with radial-flow electrochemical cell (고성능 액체 크로마토그래피/방사흐름 전기화학전지를 이용한 안트라사이클린계 항생제의 동시 정량)

  • Cho, Yonghee;Hahn, Younghee
    • Analytical Science and Technology
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    • v.20 no.4
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    • pp.308-314
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    • 2007
  • The analytical method of HPLC with the radial-flow electrochemical cell (RFEC) has been developed to determine doxorubicin, epirubicin, nogalamycin, daunorubicin and idarubicin simultaneously by employing a reversed-phase chromatography. Anthracyclines were detected at -0.74 V vs. a Ag/AgCl (0.01 M NaCl) reference electrode, a potential of diffusion current plateau in the mobile phase. At a $V_f$ of 1.0 mL/min doxorubicin, epirubicin, daunorubicin and idarubicin appeared at a retention time ($t_r$) of 6.4 min, 7.4 min, 12.7 min and 18.4 min, respectively, while at a $V_f$ of 0.6 mL/min, doxorubicin, epirubicin, nogalamycin, daunorubicin and idarubicin appeared at a $t_r$ of 9.9 min, 11.5 min, 13.5 min, 19.6 min and 28.7 min, respectively. The linearity between each anthracycline injected ($2.40{\times}10^{-7}M{\sim}1.42{\times}10^{-5}M$) and peak area (charge) was excellent with the square of the correlation coefficient ($R^2$) higher than 0.999. The detection limits were $1.0{\times}10^{-8}M{\sim}1.5{\times}10^{-7}M$ for the five anthracyclines. Within-day precision for the five anthracyclines were in reasonable relative standard deviations less than 3 % ($1.00{\times}10^{-6}M{\sim}1.42{\times}10^{-5}M$) except the lower concentrations less than $0.7{\mu}M$. Solid phase extractions of $1.00{\times}10^{-5}M$ epirubicin, $0.48{\times}10^{-5}M$ nogalamycin and $1.52{\times}10^{-5}M$ daunorubicin from human serum with a $C_{18}$ cartridge resulted in 97 %, 100 % and 90 % of recoveries, respectively.

A Case Study of Shanghai Tang: How to Build a Chinese Luxury Brand

  • Heine, Klaus;Phan, Michel
    • Asia Marketing Journal
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    • v.15 no.1
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    • pp.1-22
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    • 2013
  • This case focuses on Shanghai Tang, the first truly Chinese luxury brand that appeals to both Westerners and, more recently, to Chinese consumers worldwide. A visionary and wealthy businessman Sir David Tang created this company from scratch in 1994 in Hong Kong. Its story, spanned over almost two decades, has been fascinating. It went from what best a Chinese brand could be in the eyes of Westerners who love the Chinese culture, to a nearly-bankrupted company in 1998, before being acquired by Richemont, the second largest luxury group in the world. Since then, its turnaround has been spectacular with a growing appeal among Chinese luxury consumers who represent the core segment of the luxury industry today. The main objective of this case study is to formally examine how Shanghai Tang overcame its downfall and re-emerged as one the very few well- known Chinese luxury brands. More specifically, this case highlights the ways with which Shanghai Tang made a transitional change from a brand for Westerners who love the Chinese culture, to a brand for both, Westerners who love the Chinese culture and Chinese who love luxury. A close examination reveals that Shanghai Tang has followed the brand identity concept that consists of two major components: functional and emotional. The functional component for developing a luxury brand concerns all product characteristics that will make a product 'luxurious' in the eyes of the consumer, such as premium quality of cachemire from Mongolia, Chinese silk, lacquer, finest leather, porcelain, and jade in the case of Shanghai Tang. The emotional component consists of non-functional symbolic meanings of a brand. The symbolic meaning marks the major difference between a premium and a luxury brand. In the case of Shanghai Tang, its symbolic meaning refers to the Chinese culture and the brand aims to represent the best of Chinese traditions and establish itself as "the ambassador of modern Chinese style". It touches the Chinese heritage and emotions. Shanghai Tang has reinvented the modern Chinese chic by drawing back to the stylish decadence of Shanghai in the 1930s, which was then called the "Paris of the East", and this is where the brand finds inspiration to create its own myth. Once the functional and emotional components assured, Shanghai Tang has gone through a four-stage development to become the first global Chinese luxury brand: introduction, deepening, expansion, and revitalization. Introduction: David Tang discovered a market gap and had a vision to launch the first Chinese luxury brand to the world. The key success drivers for the introduction and management of a Chinese luxury brand are a solid brand identity and, above all, a creative mind, an inspired person. This was David Tang then, and this is now Raphael Le Masne de Chermont, the current Executive Chairman. Shanghai Tang combines Chinese and Western elements, which it finds to be the most sustainable platform for drawing consumers. Deepening: A major objective of the next phase is to become recognized as a luxury brand and a fashion or design authority. For this purpose, Shanghai Tang has cooperated with other well-regarded luxury and lifestyle brands such as Puma and Swarovski. It also expanded its product lines from high-end custom-made garments to music CDs and restaurant. Expansion: After the opening of his first store in Hong Kong in 1994, David Tang went on to open his second store in New York City three years later. However this New York retail operation was a financial disaster. Barely nineteen months after the opening, the store was shut down and quietly relocated to a cheaper location of Madison Avenue. Despite this failure, Shanghai Tang products found numerous followers especially among Western tourists and became "souvenir-like" must-haves. However, despite its strong brand DNA, the brand did not generate enough repeated sales and over the years the company cumulated heavy debts and became unprofitable. Revitalizing: After its purchase by Richemont in 1998, Le Masne de Chermont was appointed to lead the company, reposition the brand and undertake some major strategic changes such as revising the "Shanghai Tang" designs to appeal not only to Westerners but also to Chinese consumers, and to open new stores around the world. Since then, Shanghai Tang has become synonymous to a modern Chinese luxury lifestyle brand.

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Nutritional quality evaluation of complementary baby food products in Korea according to food composition (국내 시판 간편 이유식의 식품 구성에 따른 영양적 질 평가)

  • Eun-Ju Lee;Jee-Young Yeon;Mi-Hyun Kim
    • Journal of Nutrition and Health
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    • v.56 no.5
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    • pp.537-553
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    • 2023
  • Purpose: The purpose of this study was to evaluate the nutritional quality of complementary baby food products sold in Korea according to the baby food stages and food composition. Methods: A total of 1,587 complementary food products sold online and offline between March and December 2021 were investigated. They ranged from liquid meals to solid rice for babies aged 5 to 36 months. Results: The number of intakes per packaged volume was 2.8 in Stage 1, 1.9 in Stage 2, 1.4 in Stage 3, and 1.1 in Stage 4 (p < 0.0001). The dietary variety scores (DVS) of the complementary baby food products were 3.4 in Stage 1, 5.5 in Stage 2, 7.1 in Stage 3, and 9.7 in Stage 4 (p < 0.0001) and showed a significant increase in the later stages. The Korean dietary diversity score (KDDS) significantly increased from 2.3 in Stage 1, to 2.8 in Stage 2, 3.0 in Stage 3, and 3.4 in Stage 4 (p < 0.0001). The higher the baby food stage, the higher the proportion of grains/meat/vegetable ingredients. The ratio of protein intake to Adequate Intake (AI) or Recommended Nutrition Intake (RNI) was higher in products with a KDDS of 3 points or more, or in products with 2 points or fewer in Stages 1 and 2 (p < 0.0001, respectively). The ratio of protein intake to RNI increased as the KDDS score increased in Stages 3 and 4 (p < 0.0001, respectively). For all stages of baby foods, the ratio of protein intake to AI or RNI was high in products that included the meat group (beans, nuts, meat, eggs, fish, and shellfish) (p < 0.0001, respectively). Conclusion: Continuous research and nutritional evaluation are required for establishing nutrient content standards for commercially available baby foods, considering breast milk intake.

Comparative Analysis of Ginsenoside Content in Processed Red Ginseng Foods Based on Food Type and Formulation (홍삼가공식품의 식품유형별 및 제형별 진세노사이드 함량 비교)

  • Yun-Jeong Yi;Min-Su Chang;In-Sook Lee;Hyun-Jeong Kim;Hyun-Jeong Jang;In-Sook Hwang
    • Journal of Food Hygiene and Safety
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    • v.39 no.2
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    • pp.163-170
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    • 2024
  • Red ginseng is manufactured as a health-functional food and is also present in various food types and in different product forms. However, there is currently no standardized regulation of ginsenoside content in foods containing red ginseng. In the present study, we analyzed the ginsenoside content of 66 red ginseng-containing foods and 35 health-functional foods collected online and directly from the market. The ginsenoside content was assessed using liquid chromatography (LC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods. The ginsenoside content of the various food types ranged 0.0 (not detected)-71.567 mg per daily intake of foods containing red ginseng. Sugar-preserved foods had the highest ginsenoside content, followed by solid teas, liquid teas, and red ginseng beverages. For health-functional foods, the ginsenoside content ranged 3.4-58.5 mg per daily intake, with levels ranging 83-607% of the indicated amounts. All values met the established standards. Upon comparing red ginseng health-functional foods and red ginseng-containing foods, the average ginsenoside content was determined to be 18.21 and 8.79 mg, respectively, thus being nearly twice as high in health-functional foods. However, there was a minimal difference between the ginsenoside content of red and black ginseng, with values of 11.84 and 12.63 mg, respectively. These findings provide insights on the variations in ginsenoside content of red and black ginseng in various food forms. This information is expected to be valuable for future regulations and consumer choice of products containing red ginseng.

Studies on Dairy Farming Status, Reproductive Efficiencies and Disorders in New Zealand (I) A Survey on Dairy Farming Status and Milk Yield in Palmerston North Area (뉴질랜드 (Palmerston North) 의 낙농 현황과 번식 및 번식장해에 관한 연구(I) Palmerston North 지역의 낙농 현황과 우유 생산량에 관한 조사 연구)

  • 김중계;맥도날드
    • Korean Journal of Animal Reproduction
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    • v.24 no.1
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    • pp.1-18
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    • 2000
  • Eighty dairy farms in Palmers ton North area in New Zealand were surveyed on 1) general characteristics (10 Questions), 2) milk yield and feed supplementary (7 questions), 3) reproductive efficiencies (12 questions) and 4) reproductive disorders (12 questions) by mail questions from February to July, 1998. Among those 4 items from 38 dairy farms (47.5%), especially in items 1) and 2), overall dairy farming situation, supplementary feeding and milk yields were surveyed and analyzed for Korean dairy farmers (especially in Cheju island) to have better understanding or higher economical gains. The results were as follows. 1. In dairy experience, 21 (45%) among 38 dairy farms surveyed were answered that farming less than 15 years, 15~19 year, 20~25 years and over 26 years experience were 3 (7.9%), 7 (18.4%), 6 (15.8%) and 5 (13.2%) which generally showed longer experience compare to Korean dairy farming situation. In survey of labour input and business goal of dairy farming, self-managing farms, sharemilkers, unpaid family manpowering farms, manager running farms, farms with hired worker, farms with part time helper and other type was 21 (55.3%), 10 (26.3%), 2 (3.5%), 3 (5.3%), 18 (31.6%), 2 (3.5%), and 1 (1.8%), respectively. 2. Analyzing pasture and tillable land, pasture according to feeding scale (200, 300 and 400 heads) were 56, 90 and 165.3 ha, and tillable lands were 51, 78 and 165 ha which showed some differences among feeding scale. In recording methods in 38 farms replied, 36 (95%) dairy handbook and 23 (70%) dual methods taking farms were higher than that of 10 (26.3%) computer and 15(39.5%) well-recorder methods. 3. Dairy waste processing facilities in environmental field were almost perfect except of metropolitan area, and so no problem was developed in its control so far. Hence, 26 farm (68.4%) of pond system was higher rather than those in 8 (21.2%) of using as organic manure after storing feces of dairy cattle, 1(2.6%) bunker system and 3 (7.9%) other type farms. 4. In milking facilities, 33 farms (86.9%) of Harringbone types were higher than those in 3 (7.9%) of Walkthrough types, 1 (2.6%) of Rotary system and other types. Although the construction facilities was not enough, this system show the world-leveled dairy country to attempted to elevate economic gains using the advantage of climatic condition. 5. In milking day and yearly yield per head, average 275 milking days and 87 drying days were longer than that of 228 average milking days in New Zealand. Annual total milk yield per head and milk solid (ms) was 3,990 kg and approximately 319 kg. Dairy milk solid (ms) per head, milk yield, fat percentage was 1.2 kg, 15.5 kg and average 4.83% which was much higher than in other country, and milk protein was average 3.75%. 6. In coclusion, Palmerstone North has been a center of dairy farming in New Zealand for the last 21 years. Their dairy farming history is 6~9 year longer than ours and the average number of milking cows per farm is 355, which is much greater than that (35) of Korea. They do not have dairy barn, but only milking parlors. Cows are taken care of by family 0.5 persons), are on a planned calving schedule in spring (93%) and milked for 240~280 days a year, avoiding winter. Cows are dried according to milk yield and body condition score. This management system is quite different from that of Korean dairy farms. Cows are not fed concentrates, relying entirely on pasture forages and the average milk yield per cow is 3,500 kg, which is about 1/2 milk yield of Korean dairy farms. They were bred to produce high fat milk with an average of 4.5%. Their milk production cost is the lowest in the world and the country's economy relies heavily on milk production. We Korean farmers may try to increase farming size, decreasing labor and management costs.

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A study on the air pollutant emission trends in Gwangju (광주시 대기오염물질 배출량 변화추이에 관한 연구)

  • Seo, Gwang-Yeob;Shin, Dae-Yewn
    • Journal of environmental and Sanitary engineering
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    • v.24 no.4
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    • pp.1-26
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    • 2009
  • We conclude the following with air pollution data measured from city measurement net administered and managed in Gwangju for the last 7 years from January in 2001 to December in 2007. In addition, some major statistics governed by Gwangju city and data administered by Gwangju as national official statistics obtained by estimating the amount of national air pollutant emission from National Institute of Environmental Research were used. The results are as follows ; 1. The distribution by main managements of air emission factory is the following ; Gwangju City Hall(67.8%) > Gwangsan District Office(13.6%) > Buk District Office(9.8%) > Seo District Office(5.5%) > Nam District Office(3.0%) > Dong District Office(0.3%) and the distribution by districts of air emission factory ; Buk District(32.8%) > Gwangsan District(22.4%) > Seo District(21.8%) > Nam District(14.9%) > Dong District(8.1%). That by types(Year 2004~2007 average) is also following ; Type 5(45.2%) > Type 4(40.7%) > Type 3(8.6%) > Type 2(3.2%) > Type 1(2.2%) and the most of them are small size of factory, Type 4 and 5. 2. The distribution by districts of the number of car registrations is the following ; Buk District(32.8%) > Gwangsan District(22.4%) > Seo District(21.8%) > Nam District(14.9%) > Dong District(8.1%) and the distribution by use of car fuel in 2001 ; Gasoline(56.3%) > Diesel(30.3%) > LPG(13.4%) > etc.(0.2%). In 2007, there was no ranking change ; Gasoline(47.8%) > Diesel(35.6%) > LPG(16.2%) >etc.(0.4%). The number of gasoline cars increased slightly, but that of diesel and LPG cars increased remarkably. 3. The distribution by items of the amount of air pollutant emission in Gwangju is the following; CO(36.7%) > NOx(32.7%) > VOC(26.7%) > SOx(2.3%) > PM-10(1.5%). The amount of CO and NOx, which are generally generated from cars, is very large percentage among them. 4. The distribution by mean of air pollutant emission(SOx, NOx, CO, VOC, PM-10) of each county for 5 years(2001~2005) is the following ; Buk District(31.0%) > Gwangsan District(28.2%) > Seo District(20.4%) > Nam District(12.5%) > Dong District(7.9%). The amount of air pollutant emission in Buk District, which has the most population, car registrations, and air pollutant emission businesses, was the highest. On the other hand, that of air pollutant emission in Dong District, which has the least population, car registrations, and air pollutant emission businesses, was the least. 5. The average rates of SOx for 5 years(2001~2005) in Gwangju is the following ; Non industrial combustion(59.5%) > Combustion in manufacturing industry(20.4%) > Road transportation(11.4%) > Non-road transportation(3.8%) > Waste disposal(3.7%) > Production process(1.1%). And the distribution of average amount of SOx emission of each county is shown as Gwangsan District(33.3%) > Buk District(28.0%) > Seo District(19.3%) > Nam District(10.2%) > Dong District(9.1%). 6. The distribution of the amount of NOx emission in Gwangju is shown as Road transportation(59.1%) > Non-road transportation(18.9%) > Non industrial combustion(13.3%) > Combustion in manufacturing industry(6.9%) > Waste disposal(1.6%) > Production process(0.1%). And the distribution of the amount of NOx emission from each county is the following ; Buk District(30.7%) > Gwangsan District(28.8%) > Seo District(20.5%) > Nam District(12.2%) > Dong District(7.8%). 7. The distribution of the amount of carbon monoxide emission in Gwangju is shown as Road transportation(82.0%) > Non industrial combustion(10.6%) > Non-road transportation(5.4%) > Combustion in manufacturing industry(1.7%) > Waste disposal(0.3%). And the distribution of the amount of carbon monoxide emission from each county is the following ; Buk District(33.0%) > Seo District(22.3%) > Gwangsan District(21.3%) > Nam District(14.3%) > Dong District(9.1%). 8. The distribution of the amount of Volatile Organic Compound emission in Gwangju is shown as Solvent utilization(69.5%) > Road transportation(19.8%) > Energy storage & transport(4.4%) > Non-road transportation(2.8%) > Waste disposal(2.4%) > Non industrial combustion(0.5%) > Production process(0.4%) > Combustion in manufacturing industry(0.3%). And the distribution of the amount of Volatile Organic Compound emission from each county is the following ; Gwangsan District(36.8%) > Buk District(28.7%) > Seo District(17.8%) > Nam District(10.4%) > Dong District(6.3%). 9. The distribution of the amount of minute dust emission in Gwangju is shown as Road transportation(76.7%) > Non-road transportation(16.3%) > Non industrial combustion(6.1%) > Combustion in manufacturing industry(0.7%) > Waste disposal(0.2%) > Production process(0.1%). And the distribution of the amount of minute dust emission from each county is the following ; Buk District(32.8%) > Gwangsan District(26.0%) > Seo District(19.5%) > Nam District(13.2%) > Dong District(8.5%). 10. According to the major source of emission of each items, that of oxides of sulfur is Non industrial combustion, heating of residence, business and agriculture and stockbreeding. And that of NOx, carbon monoxide, minute dust is Road transportation, emission of cars and two-wheeled vehicles. Also, that of VOC is Solvent utilization emission facilities due to Solvent utilization. 11. The concentration of sulfurous acid gas has been 0.004ppm since 2001 and there has not been no concentration change year by year. It is considered that the use of sulfurous acid gas is now reaching to the stabilization stage. This is found by the facts that the use of fuel is steadily changing from solid or liquid fuel to low sulfur liquid fuel containing very little amount of sulfur element or gas, so that nearly no change in concentration has been shown regularly. 12. Concerning changes of the concentration of throughout time, the concentration of NO has been shown relatively higher than that of $NO_2$ between 6AM~1PM and the concentration of $NO_2$ higher during the other time. The concentration of NOx(NO, $NO_2$) has been relatively high during weekday evenings. This result shows that there is correlation between the concentration of NOx and car traffics as we can see the Road transportation which accounts for 59.1% among the amount of NOx emission. 13. 49.1~61.2% of PM-10 shows PM-2.5 concerning the relationship between PM-10 and PM-2.5 and PM-2.5 among dust accounts for 45.4%~44.5% of PM-10 during March and April which is the lowest rates. This proves that particles of yellow sand that are bigger than the size $2.5\;{\mu}m$ are sent more than those that are smaller from China. This result shows that particles smaller than $2.5\;{\mu}m$ among dust exist much during July~August and December~January and 76.7% of minute dust is proved to be road transportation in Gwangju.

A Study on the Traumatic Teeth Damage of Children (어린이의 외상성 치아손상에 관한 연구)

  • Yoo, Su-Min;Park, Ho-won
    • Journal of dental hygiene science
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    • v.4 no.1
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    • pp.21-25
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    • 2004
  • In modern times, children's trauma is increasing every year because of car accidents and life environment changes. There is a limit to prevent traumatic damage for oral cavity organization. The fundamental data of trauma treatment and prevention will be presented through the survey and analysis of traumatic teeth damage. I examined 113 patients from Oct. 4th, 2000 to Feb. 27th, 2004 at Dept. of Children's Dental Clinic, Kangnung National University. The results are as follows. (1) The trauma frequency of male subjects is higher than that of female at a rate of 2.05:1. The average age is 5.27 for men and 5.27 for women. The highest percentage of trauma patients is among 2 year old children. It is 21.2%. (2) A patient survey was taken at a trauma treatment hospital. On the first day 34.4% of the patients had come to receive treatment of their first set of teeth. However, after a week, 38.8% of the patients had received treatment on their permanent teeth. (3) As a result of falling, 59% of patients needing treatment on their first set of teeth. 55.1% of patients is permanent teeth. As a result of bump against physical solid, 26.6% of patients is the first set of teeth and 26.5% of patients is permanent teeth. (4) Teeth damage happened at home. 42.1% were male. 35.1% were female. According to trauma, 59.4% of teeth damage happened at home. 28.6% of permanent teeth damage happened at school or kindergarten. (5) According to trauma, the number of teeth damaged was in the first set of teeth are as follows: 56.3%, one-31.3%, three or four-6.3% each. For permanent teeth: two-46.9%, one-28.6%, four over-16.3% and three-8.2%. Over four teeth is larger number for permanent teeth. (6) 56% of first set of teeth patients and 43.4% of permanent teeth patients were male. 56.8% of first set of teeth patients and 43.2% of permanent teeth were female. Trauma happened to both male and female frequently in the first set of teeth. (7) Most of the tooth damage which was in the first set of teeth and permanent teeth was done to the upper jaw. 75% of patients are the first set of teeth. 63.8% of patients are permanent teeth. Trauma is very high in the two mid teeth of the upper jaw. (8) According to trauma survey, 30.2% is from impulse. 28.0% is from crown fracture, 14.7% is from depression. 8.9% is from concussion. 7.1% is from full dislocation of a joint. 2.2% of patients are extrusion. 1.8% is from displacement. According to teeth damage trauma, 35.8% is pulse in the first set of teeth. The breaking of the crown of a tooth happened a lot in permanent teeth. (9) According to data, 43.2% of teeth damage in the first set of teeth goes without treatment. In permanent teeth, it is 38.9%. After treatment, 22.0% of first set of teeth treatment requires a dental pulp treatment. In permanent teeth, which is used for temporary acid etching resin restoration.

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