• Title/Summary/Keyword: 혼합토

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Relationship on the Refractive Status of the High School 3rd Grade Students with Subnormal Visual Acuity in Gwangju Metropolitan City (광주지역 고등학교 3학년생의 비정시안의 굴절상태에 대한 고찰)

  • Yoon, Young;Ryu, Geun-Chang
    • Journal of Korean Ophthalmic Optics Society
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    • v.12 no.3
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    • pp.105-110
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    • 2007
  • To investigate the ametropia and refractive error of 222 ametropic eyes of the 111 high school students in Gwangju Metropolitan City, the visual acuity test was performed by the object and subject method. 85% of the eye types were positive for myopia, 14% for emmetropia, and 1% for hyperopia, respectively. 38% of the abnormal refraction eyes were positive for simple myopia, 4% for myopia simple astigmatism, 56% for myopia compound astigmatism, and 0% for simple hyperopia, 0% for hyperopia simple astigmatism, 2% for hyperopia compound astigmatism, 0% for mixed astigmatism, respectively. 92% of the axes fo astigmatism were for astigmatism with-the-rule, 6% for astigmatism against-the rule, 2% for astigmatism oblique, respectively. As for the astigmatic power, 0.50 < cylinder < 1.00D was 68%, 1.00 < cylinder < 2.00D was 25%, and anything over the 2.00 cylinder D was 7%. As for the equivalent spheric power of myopic abnormal refraction eyes, -0.50 < spheric equivalent < -2.00D was 26%, -2.00D < spheric equivalent < -6.00D was 55% and anything over the -6.00D was 19%. The rate of wearing glasses was 74%. It increases compared to 20 years ago. 91% of the eye test place was the optical shop, 9% the eye doctor hospital. 80% of the students need to change their optical lenses because spherical equivalent power was over 0.50D.

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규산나트륨을 이용한 졸-겔 구형 $SiO_2$ 나노졸 합성 연구

  • Gwon, Il-Jun;Park, Seong-Min;Kim, Myeong-Sun;Sim, Ji-Hyeon;Yeom, Jeong-Hyeon
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2012.03a
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    • pp.111-111
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    • 2012
  • 나노테크놀로지는 종래의 가공으로는 얻기 힘들었던 섬유가공 효과를 간단하게 할 수 있는 기술이다. 현재 각국의 기능성 나노 가공제를 섬유에 응용하는 나노 테크놀로지는 현재 공업 생산되고 있는 면, 모, 견 등의 천연섬유 및 polyester, Nylon 등의 합성섬유의 원단에 적용하는 데서 출발하고 있다. 이러한 나노기술은 기존의 설비와 물을 사용하는 것이 큰 특징이고, 특별한 기계장치가 필요하지 않으며, 소규모의 실험장비만 있어도 현장투입이 가능한 나노입자의 제조가 가능하기 때문에 대량생산이 용이하고 설비투자는 원칙적으로 필요하지 않는다. 또한, 나노입자의 분산을 제대로 시키면 그 사이즈가 빛의 가시광선 영역의 파장(400~800nm)에 비해 절반 수준이하 크기의 입자가 대부분을 차지하기 때문에 염색성, 태의 변화가 적어 앞으로 더욱더 나노테크놀로지에 의한 가공이 확대될 것이 예상된다. 특히 유 무기 하이브리드 재료는 용액상태에서 제조되기 때문에 용액 코팅공정의 적용이 가능하여 다양한 코팅에 적극적으로 활용되고 있다. 또한 코팅공정 온도가 상대적으로 낮아서, 유기물의 기능성 발현이 용이하며, 섬유가공에 그대로 적용이 가능하고, 섬유고분자와 내구성 있게 직접 결합이 되어 실용성이 높다 할 수 있다. 또한 나노졸의 형성 시, 혹은 나노졸에 기능성 물질을 첨가함으로서 나노졸과 기능성 물질을 복합화하여 섬유상에 부여하는 것도 가능하다. 최근에 실리카졸의 형성과 성장에 관한 연구는 졸-겔 기술의 발전과 해석 및 상용화에 집중되어 있다. 규산나트륨과 황산 또는 염산을 사용하여 실리카를 생성하는 공정은 tetraethoxysilane (($Si(OC_2H_5)_4$, (TEOS))를 이용하여 합성하는 방법과 달리 대량의 실리카를 경제적으로 생산하는데 방법으로 널리 연구되고 있지만, 많은 연구가 수행되었음에도 불구하고 실리카 졸의 특성, 성장, 제조에 대한 충분한 이해가 이루어 지지 않고 있어, 아직까지 나노크기의 입자를 제조하는 공정에 대해서는 경제성, 효율성, 품질의 균일성이 떨어지는 것이 현실이다. 따라서 본 연구에서는 앞서 연구된 졸-겔 합성기술과 저렴한 원료인 규산나트륨을 이용하여 보다 간단하고 경제적인 방법으로 고부가가치의 다양한 실리카 나노졸을 제조할 수 있는 연구를 하고자 하였다. 이를 위해 규산나트륨 수용액의 특성, 핵 생성에 필요한 규산나트륨 수용액의 산화반응 특성, 그리고 출발용액의 졸겔 반응을 기초로 하여 실리카 졸 형성에 대한 반응물질의 혼합방법, 반응온도, 반응물의 농도, pH등이 최종 실리카 나노졸 제품의 입자 크기와 모양 등에 미치는 영향을 조사하려고 하며 이를 토대로 다양한 크기와 특성을 가진 실리카 나노졸을 제조하였다.

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Geochemical Significance of $^{14}C$ Age from the Dongrae Hot Spring Water (동래온천수의 $^{14}C$ 연대의 지구과학적 의의)

  • Lee, Seung-Gu;Nakamura, Toshio;Kim, Tong-Kwon;Ohta, Tomoko;Kim, Hyoung-Chan;Lee, Tae-Jong
    • Economic and Environmental Geology
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    • v.42 no.6
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    • pp.541-548
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    • 2009
  • The Dongrae thermal water area located at the southeastern marginal part of the Korean Peninsula is one of the oldest hot springs in Korea. The Dongrae thermal water shows Na-Cl type of water chemistry, whereas the shallow cold groundwater is Ca(-Na)-$HCO_3$ type. In this paper, we discuss the age of the Dongrae hot spring, i.e. groundwater cycle among meteoric water-surface water-shallow groundwater-hot spring water. The $^{87}Sr/^{86}Sr$ ratios of the thermal water in Dongrae area range from 0.705663 to 0.705688 and are lower than those of groundwater, surface water and rain water as well as aquifer bearing granite. These Sr isotopic signatures in the Dongrae thermal water indicate that the circulation rate between thermal water and current meteoric water including groundwater, surface water and rain water in the Dongrae area should be very slow. The $^{14}C$ age of the Dongrae hot spring water range from $1,271{\pm}36$ BP(before present) to $2,467{\pm}36$ BP whereas that of the shallow groundwater is $-495{\pm}33$ BP. This suggests that the period of groundwater cycle among meteoric water, surface water, shallow groundwater and hot spring should be more than 1,270 years. Then, it also indicates that the present Dongrae hot spring may be a mixed water between the old thermal water heated for at least 1,270 years and the present shallow cold groundwater.

Effect of Solidified/Stabilized Sewage Sludge using Neutral Solidifying Chemical Agent and Alkaline Agent as Landfill Cover on Decomposition of Organic Matter in Lysimeter (중성계 및 알칼리성 고화재를 이용한 고화하수슬러지의 복토재가 모형매립조 내 유기물 분해에 미치는 영향)

  • Kim, Hye-Jin;Park, Jin-Kyu;Song, Sang-Hoon;Lee, Nam-Hoon
    • Journal of Korean Society of Environmental Engineers
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    • v.30 no.8
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    • pp.768-774
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    • 2008
  • To evaluate the effect of the solidified/stabilized sewage sludge on landfill sites, lysimeter tests were conducted. Lysimeters (LR1, LR2, and LR3) were filled with the material(Compost : Fodder : Sand = 10 : 10 : 80) and covered with different types of the cover soils, the G solidified sludge produced from the neutral solidifying chemical agent(LR1), the A solidified sludge produced from the alkali solidifying chemical agent(LR2), and the weathered granite soil(LR3). Those lysimeters were kept at the temperature controlled room with 30 $\pm$ 2$^{\circ}C$ for about 450 days. As the results, it was appeared LR2 > LR1 > LR3 that total gas production rate(L), gas production rate(L/VS(kg)) and cumulative gas(CO$_2$ + CH$_4$) production. There were not significant differences at decrease of the COD$_{Cr}$ in the leachate from LR1 and LR3. Thus, it had been shown that the use of the G solidified sludge as cover soil did not affect the COD$_{Cr}$ in the leachate. The COD$_{Cr}$ from LR2 had been increased since around 250 days because solidified/stabilized sewage sludge became re-slurry. T-N and T-P from LR3 also were higher than LR1 and LR2. Also were, the use of the solidified/stabilized sewage sludge as a cover soil, therefore, did not affect the T-N and T-Pconcentrations in the leachate.

Determinants of the Ownership Structure of Franchise Systems: Theory and Evidence (프랜차이즈 시스템의 소유구조 결정요인: 이론과 증거)

  • Lim, Young-Kyun;Byun, Sook-Eun;Oh, Seung-Su
    • Journal of Distribution Research
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    • v.16 no.3
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    • pp.33-75
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    • 2011
  • The ownership structure of a franchise system is determined by the franchisor's strategic choice. A close look at the extant theories and perspectives in economics and management such as resource scarcity theory, agency theory, transaction cost analysis, and mixed ownership theory reveals that firms choose their ownership structure for the sake of economic efficiency, profit potentials, the chance of survival, and other strategic concerns. The present study, on the basis of strategic choice perspective, reviews the divergent theories of a franchise system's ownership structure and its determinants, thus providing a theoretical framework for comparing the contradictory arguments along the several critical dimensions. We also developed and tested the conflicting hypotheses regarding key determinants of ownership structure including firm's age, size, transaction-specific investments, uncertainty, and risk-sharing propensity. Using a FDD (Franchise Disclosure Document) data set of 543 Korean franchisors, we found that the years in business, the total number of employees, days of training, the inverse of the years of franchising, and the requirement of royalty payment have positive relationships with the proportion of company-owned outlets to total number of outlets. On the other hand, the proportion of company-owned outlets was found to have negative relationships with the total number of outlets and the extent of geographic dispersion of outlets, but to have no significant relationships with the initial investment required and the inverse of contract length. Based on the findings, we provide several theoretical and managerial implications for studying ownership structure of franchise systems.

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A New Face Tracking and Recognition Method Adapted to the Environment (환경에 적응적인 얼굴 추적 및 인식 방법)

  • Ju, Myung-Ho;Kang, Hang-Bong
    • The KIPS Transactions:PartB
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    • v.16B no.5
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    • pp.385-394
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    • 2009
  • Face tracking and recognition are difficult problems because the face is a non-rigid object. The main reasons for the failure to track and recognize the faces are the changes of a face pose and environmental illumination. To solve these problems, we propose a nonlinear manifold framework for the face pose and the face illumination normalization processing. Specifically, to track and recognize a face on the video that has various pose variations, we approximate a face pose density to single Gaussian density by PCA(Principle Component Analysis) using images sampled from training video sequences and then construct the GMM(Gaussian Mixture Model) for each person. To solve the illumination problem for the face tracking and recognition, we decompose the face images into the reflectance and the illuminance using the SSR(Single Scale Retinex) model. To obtain the normalized reflectance, the reflectance is rescaled by histogram equalization on the defined range. We newly approximate the illuminance by the trained manifold since the illuminance has almost variations by illumination. By combining these two features into our manifold framework, we derived the efficient face tracking and recognition results on indoor and outdoor video. To improve the video based tracking results, we update the weights of each face pose density at each frame by the tracking result at the previous frame using EM algorithm. Our experimental results show that our method is more efficient than other methods.

Comparative Study of Educational Needs between Public Officials and Private Employees for Health and Welfare (보건복지전담 공무원과 민간 보건복지종사자의 교육요구 비교)

  • Song, Yun-Hee;Eom, Mi-Ri;Jin, Sun-Mi
    • Journal of Convergence for Information Technology
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    • v.8 no.1
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    • pp.207-214
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    • 2018
  • The purpose of this study is to compare the educational needs of public officials and private employees for health and welfare in order to improve education program. Data were collected from 2,290 public officials and 1,991 private employees and were analyzed using frequency analysis and independent sample t-test. Private employees recognized that education and training are more enough than public officials. In addition, private employees took the gathering training classes more than public officials. Private employees reported that they are more satisfied than public officials with regard to leader consideration, peers' will of participation and institutional conditions. However, public officials reported that they are more satisfied than private employee officials with regard to the degree of sharing of information and education for new policies. Public officials preferred three or two days of training, but private employees preferred one or two days. Both public officials and private employees preferred gathering training classes and blended learning as an effective education type. Based on this research, invigoration of health and welfare education and the management of its plan were discussed.

Group Brainstorming Activity according to Sasang Constitutional Medicine (사상체질 분류에 의한 브레인스토밍 집단 구성 연구)

  • Jeon, Kyung-won
    • Journal of Sasang Constitutional Medicine
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    • v.12 no.1
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    • pp.48-62
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    • 2000
  • Creativity is the most important characteristic and ability in the 21st century. Recently leading people in Korean society are aware of the significance of the enhancement of the creativity. However, Korean students are less likely to take initiative or depart from standard ways of thinking or doing things, because Korean Confucius culture puts an emphasis on collectivism. An individual has an obligation to conform in order to avoid conflict and maintain social harmony. The rule of respecting parents and teachers leads to a lack of self-expression and entails silence. Brainstorming technique developed by American Osbron, who originated the group brainstorming in 1953, is the most popular creative thinking method for the students. Brainstorming technique has two principles : ideation can be more productive if criticism is concurrently excluded; The more ideas the better. In doing BS, each panel should consist of chairperson, an assistant chairperson, recorder, and 10 others including 2-3 females. However there are several problems in doing group BS, such as production blocking, uniformity thinking, evaluation apprehension, and social loafing. This study was undertaken to investigate the proper way of forming Brainstorming groups with Korean students according to the Sasang Constitutional Medicine originated by Korean Lee Je-ma in 1894. Human beings are classified in four group in Sasang Constitutional Medicine : Taeyang-In, Teaum-In, Soyang-In and Soum-In. Two Yang-Ins are more self-expressive : Taeyang-In has very unique ides and thoughts; Soyang-In is very humorous and like to present his/her ideas. On the other hand, two Um-Ins are passive and are not likely to speak out their ideas in group. Therefore, in this investigation firstly, the brainstorming group was formed with two Yang-Ins (Taeyang-In and Soyang-In) and two Um-Ins(Taeum-In and Soum-In) separately and secondly, Yang-Ins and Um-Ins were mixed. And the first method was compared with the second method in terms of the degree of participation of the group members and finally the better grouping method to produce more and better ideas was discussed and suggested for the educational system.

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Changes in quality characteristics of salted Kimchi cabbage and kimchi paste during storage (절임배추 및 김치 양념의 저장기간 중 품질 특성 변화)

  • Song, Hye-Yeon;Cheon, Seon-Hwa;Yoo, SeungRan;Chung, Young Bae;Seo, Hye-Young
    • Food Science and Preservation
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    • v.23 no.4
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    • pp.459-470
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    • 2016
  • This study was conducted to determine the potential use for salted Kimchi cabbage and kimchi paste by analyzing the quality characteristic of kimchi prepared with stored them. Salted Kimchi cabbages were packed with the 2% brine and kimchi paste were stored at $4^{\circ}C$ for 8 weeks, respectively. Kimchi prepared at 0 day and kimchi prepared with stored salted Kimchi cabbage and kimchi paste every week were stored at $4^{\circ}C$ for 8 weeks. The salinity and titratable acidity of salted Kimchi cabbage packed with the brine was lower than control. The results of salinity, pH and moisture contents of kimchi paste did not show any significant differences during storage, however, the titratable acidity was increased. In sensory evaluation, salted Kimchi cabbage packed with the brine showed higher score in overall preference than control. Kimchi paste showed 4.9~6.1 score in overall preference during storage. The titratable acidity of kimchi prepared with stored salted Kimchi cabbage and kimchi paste was lower than control. But, the results of sensory evaluation did not show significant difference among treatments. The study suggested that the use of 2% brine is an effective way for extending shelf-life of salted Kimchi cabbage and Kimchi prepared with stored salted Kimchi cabbage and kimchi paste every week is effective to delay the fermentation but no difference in sensory evaluation.

Plug Seedling Production Using Tissue Cultue Regenerants and Their Seeds in Bupleurum falcatum L. (자호(紫胡)의 조직배양묘(組織培養苗)와 배양식물(培養植物)의 종자(種子)를 이용(利用)한 프러그묘(苗) 생산(生産))

  • Park, Cheol-Ho;Yu, Chang-Yeon;Seo, Jeong-Sik;Kim, Ki-Sik;Park, Seung-Ue;Chang, Byoung-Ho;Ahn, Sang-Deuk
    • Korean Journal of Medicinal Crop Science
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    • v.3 no.3
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    • pp.207-216
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    • 1995
  • This study was conducted to establish technologies for plug seedling production using somatic embryos-derived regenerants and their seeds in Bupleurum falcatum L. Among distilled water, GA (0.1mg/l) and putrescine (0.lmg/l) treated to regenerants for acclimatization, GA was most effective to develop shoots and roots, 1/2X MS medium and NAA 0.1mg/l + BA 0. 5mg/l enhanced the growth rates of the regenerants and increased dry weight. Activated charcoal effected to grow markedly leaves and roots of the regenerants at the level of 0.4 %. Regenerants increased their plant height, root length and dry weight at $30^{\circ}C$. Plug seedlings originated from seeds of the tissue culture regenerants showed the maxium growth on the mixture of peatmoss soil (2) and mountain sand (1) .Root length, leaf area and dry weight of plug seedlings increased significantly when No.1, 2 and 3 of Wondergrow solution were mixed in the ratio of 1.3 - 0.9 - 0.1. Light supplement (4%) and high tem­perature $(30^{\circ}C)$ promoted the growth of plug seedlings as well as dry weight. Ninety days seedlings were more vigorous and adaptable for transplanting than other seedlings.

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