• Title/Summary/Keyword: 극복요인

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In Situ Surfactant Flushing of Contaminated Site (계면 활성제를 이용한 In Situ 토양 세척)

  • 염익태;안규홍
    • Journal of Korea Soil Environment Society
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    • v.2 no.2
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    • pp.9-24
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    • 1997
  • Surfactant-aided in situ soil flushing has been proposed as an alternative for the expensive and time consuming 'pump and treat' technology in remediation of contaminated soil and groundwater Injected surfactants can effectively solubilize contaminants sorbed to the soil matrix or nonaqueous phase liquids(NAPLs) in residual saturation. The contaminants solubilized in groundwater are recovered and treated further. The theoretical background of the technology and the results of the field operations, mostly in the US. were summarized. In addition, the factors crucial to the successful application of the technology were discussed. Cost analyses and technical limitations in current applications were also discussed. In conclusion, it is likely that in situ surfactant flushing become a viable option for soil remediation in limited cases. Currently, further advances with respect to operation cost and to treatment efficiency are required for more extensive application of the technology. However, the current trends in soil remediation, specially the growing emphasis on risk based corrective action and natural attenuation, will increase the competitiveness of the technology. For example, removal of easily washable contaminants by short term soil flushing followed by long term monitoring and natural attenuation can greatly reduce the operation cost and time.

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THE EFFECTS OF DRYING AGENTS AND BONDING AGENTS ON THE SHEAR BOND STRENGTH OF SEALANTS TO ENAMEL (치면건조제와 접착제의 사용에 따른 치면열구전색재의 전단결합강도에 관한 연구)

  • Lim, Hyun-Hwa;Jang, Ki-Taek;Kim, Chong-Chul;Hahn, Se-Hyun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.30 no.2
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    • pp.196-203
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    • 2003
  • The application of sealants is a highly technique-sensitive procedure, requiring an extremely dry field prior to placement. Moisture contamination of the etched enamel surface before sealant placement is cited as the main reason for sealant failure. The purpose of this study was to evaluate the effects of different methods of sealant application on the shear bond strength of sealants to enamel. In groups 1, 2, 3, 4 Teethmate(unfilled sealant) was used, while Ultraseal XTplus(filled sealant) was used in groups 5, 6, 7, 8. Groups 1 and 5(control) were acid etched for 15 seconds using 35% phosphoric acid, washed and then dried. In groups 2, 6 drying agents were applied, and in groups 3, 7 bonding agents were applied and light cured. In groups 4 and 8 both drying agent and bonding agent were applied. Then sealant was cured to the specimen using molds 3mm in diameter and 2mm in height. Thermocycling was performed and shear bond strength was finally measured. The following results were obtained : 1. Groups using filled sealant(groups 5, 6, 7, 8) showed higher shear bond strengths compared to groups using unfilled sealant(groups 1, 2, 3, 4). 2. Among groups using unfilled sealant(groups 1, 2, 3, 4), groups 2, 3, 4 showed significantly higher shear bond strength compared to group 1(p<0.05). There were no significant differences among groups 2, 3 and 4. 3. There were no significant differences(p>0.05) among groups using filled sealant(groups 5, 6, 7, 8). 4. When modes of fracture were examined, cohesive failure was observed in groups 2, 3 and 4.

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An analysis of the Domestic Interior Materials as the Ecological Design Aspects (친환경측면에서 본 국내 실내건축자재의 현황 조사 및 분석)

  • Chun Jin-Hie;Kim Jung-Ah
    • Archives of design research
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    • v.19 no.4 s.66
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    • pp.133-144
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    • 2006
  • According to the latest report by the Customer Protection Board, those who moved into newly constructed buildings are complaining about unidentified pains, asking for more careful selection of constructive materials for prevention of such potential problems. It is internationally recognized today that ecological materials can serve a significant factor for users' health, environmental protection and better industrial competitiveness. This study examined eco-design aspects of each interior material through web site search, in order to help customers learn about and capitalize on eco materials in a proper manner. As a result, 1. It turned out that the domestic industry are giving an impetus to releasing new eco items focusing on lower VOCs emission or addition of functional components as part of the marketing strategy. However, it is recommended that company understand significance of life cycle, and produce eco-concept materials. 2. The reliable standard for choosing the domestic material is EL, HB, GR marks. It is desirable to enhance recycling technologies and expand the sustainable consumption. customer class, since many recycled items are not developed. 3. The sourcing is a vulnerable part in terms of the concept of being environment-friendly material. Therefore, many manufacturers should design the easy knock-down products and produce the good items using recycled materials instead of new raw materials. Also solutions for making the energy from burning material should be studied. 4. The guidebook or manual with correct information about eco-materials is required to promote production and consumption with sustainable concept. 5. Many manufacturers are emphasizing ecological materials for customers, but some of them intended to disrupt customers' proper selection by promoting even unverified items to be environment-friendly.

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가족과 함께하는 창의성 경진대회 평가연구

  • 송규운;황동주;윤정진
    • Journal of Gifted/Talented Education
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    • v.11 no.2
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    • pp.127-150
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    • 2001
  • The upcoming century is a knowledge based society which did not exist before which requires creative ability to solve problems. Therefore, it is necessary to Provide a creative program of problem solution in order to match this global trend The creativity of problem solution means the ability to solve a problem using previous ideas in an advanced way or develop new ideas. Creative education is especially important for infants. Because the young mind is where fresh ideas preside and can frame-work the early stage of life like a blank sheet of paper. The Infant-Early Child Creative Development Institute. as an adhesive institute at Yeungjin College, develops various programs that integrate methods which match current trend in this era and also start the Creative Promotion Test with 2,000 Families for the expansion of creative education from the baseline as an alternative method. The infants tested in the creative test will find ways of problem solution through animation beam projects for their given situation and also discuss the problems with their family members. Through these processes the infant and family members will complete the creative structures to solve the problems using limited materials given by the institute, and the final product will be evaluated as objective results. The final evaluation of the test will also be considered the teamwork of family cooperation and the attitudes of participants as well as the product of problem solution. The criterion of the evaluation is to be considered both a creative way of thinking and creative attitudes. Because the score counts were conducted manually it delayed the selection of awarded students who took the test. Also, we found that some parents have difficulty in accessing information to find the score through homepage from the computer. this Problem might be corrected in the future plan. Like Freud's saying, if human character and exploring attitudes during the early stage of a child, a person's creativity is composed their infant period as their basic foundation. Therefore, the family wh first environment the infant encounters will be treated as a prima when making basic structure. From this viewpoint, this creative test work as a festival of creativity fare with 2,000 families.

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Recontextualizing geography curriculum:society;student and discipline of geography (地理 敎育課程의 再脈絡化)

  • Seo, Tae Yeol
    • Journal of the Korean Geographical Society
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    • v.29 no.4
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    • pp.438-449
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    • 1994
  • This paper focuses on recontextualizing geography curriculum, i.e. examining recent changing aspects in three geography curriculum locators-society, student and discipline of geography-and searching future directions of geography curriculum in light of such changes. For conciliation and reflection of changing aspects of each locators, this paper dealt with social issues and societal changes in terms of locator of society, increased concern to student and development of cognitive science in terms of students, and challenging views on science and the meaning of epistemological changes in geography in terms of discipline. As a result, three future directions in geography curriculum are searched : issue-based geography curriculum, thinking geography curriculum, geography curriculum toward equity and accessbility.

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Lessons from Cross-Scale Studies of Water and Carbon Cycles in the Gwangneung Forest Catchment in a Complex Landscape of Monsoon Korea (몬순기후와 복잡지형의 특성을 갖는 광릉 산림유역의 물과 탄소순환에 대한 교차규모 연구로부터의 교훈)

  • Lee, Dong-Ho;Kim, Joon;Kim, Su-Jin;Moon, Sang-Ki;Lee, Jae-Seok;Lim, Jong-Hwan;Son, Yow-Han;Kang, Sin-Kyu;Kim, Sang-Hyun;Kim, Kyong-Ha;Woo, Nam-Chil;Lee, Bu-Yong;Kim, Sung
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.9 no.2
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    • pp.149-160
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    • 2007
  • KoFlux Gwangneung Supersite comprises complex topography and diverse vegetation types (and structures), which necessitate complementary multi-disciplinary measurements to understand energy and matter exchange. Here, we report the results of this ongoing research with special focuses on carbon/water budgets in Gwangneung forest, implications of inter-dependency between water and carbon cycles, and the importance of hydrology in carbon cycling under monsoon climate. Comprehensive biometric and chamber measurements indicated the mean annual net ecosystem productivity (NEP) of this forest to be ${\sim}2.6\;t\;C\;ha^{-1}y^{-1}$. In conjunction with the tower flux measurement, the preliminary carbon budget suggests the Gwangneung forest to be an important sink for atmospheric $CO_2$. The catchment scale water budget indicated that $30\sim40%$ of annual precipitation was apportioned to evapotranspiration (ET). The growing season average of the water use efficiency (WUE), determined from leaf carbon isotope ratios of representative tree species, was about $12{\mu}mol\;CO_2/mmol\;H_2O$ with noticeable seasonal variations. Such information on ET and WUE can be used to constrain the catchment scale carbon uptake. Inter-annual variations in tree ring growth and soil respiration rates correlated with the magnitude and the pattern of precipitation during the growing season, which requires further investigation of the effect of a monsoon climate on the catchment carbon cycle. Additionally, we examine whether structural and functional units exist in this catchment by characterizing the spatial heterogeneity of the study site, which will provide the linkage between different spatial and temporal scale measurements.

A Study on the Essence and Tendency of Modern Manager (현대 경영자로서의 본질과 성향 연구)

  • Yeom, Bae-Hoon;Kim, Hyunsoo
    • Journal of Service Research and Studies
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    • v.10 no.3
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    • pp.23-42
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    • 2020
  • This study conceptualized the essence and propensity of modern management in service age, based on philosophy, and developed items to evaluate the conceptualized content. It was carried out as a new study to deepen the study of management philosophy and management theory by the new management framework. In order to establish the philosophical foundation of the modern management, the essence of the modern management was conceptualized based on the fundamental ideas of the East and West, and then an evaluation item was developed to put the essence and propensity of the modern management into practical use through analytical and empirical methods. After analyzing the representative ideas of mankind, it was derived that the Book of Change has the qualification as a philosophical model that can derive the essence of modern management. The Book of Change explains the reasoning of the world in the structure of two opposing parties, such as Taiji or Yin and Yang, and the process of acknowledging the contradictions within each opposing party and overcoming the contradictions through change is the central idea. Because you can see. After conducting a conceptual study, through empirical research, the essence and propensity of a modern manager should be conceptualized. The concept of essence and empirical study of the modern management using the leading role was conducted in two stages. First, a qualitative study using repetitive comparative analysis (CCM), focus group interview (FGI), and text mining was conducted to derive the essential and propensity conceptualization items that modern managers should possess. In addition, a quantitative study using factor analysis to develop sample items and develop measurement items through literature review and FGI was conducted to derive the essential concept of the modern management. Finally, the essence of modern management was derived: learning, preparation, challenge, inclusion, trust, morality, and sacrifice. In the future, it is necessary to conduct empirical research on the effectiveness of the essence of modern management for global and Korean representative companies.

Factors Required to Sustain Pastoral Farming Systems and Forage Supply In Winter-Cold Zones in Canada (캐나다의 동계한냉지역에 있어서 초지개발과 조사료 공급의 활성화에 필요한 요인)

  • Kunelius, H.T.;Fraser, Joanna
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.12 no.3
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    • pp.3-12
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    • 1992
  • Forage grasses and legumes ar$\varepsilon$ the mam component of livestock diets in Canada. There are over 30 million ha of grassland in Canada and there is a large, undeveloped land base in fringe areas suitable for forage production. The short growing s season limits the grassland farming to the southern p parts of Canada. The win!er season is long and in most parts of Canada cold temperatures, fr$\varepsilon$ezmg, and thawing, and diseases exert sever$\varepsilon$ stress on overwintering forage plants. The development of persistent cultivars is essential for sustained production particularly in the fringe areas with short growmg s$\varepsilon$ason. The seasonality of dry matter production is a result of high growth rates in early summ$\varepsilon$r and low dry matter accumulation in late summer and fall. Innovative management practIces a and cultivars with improved regrowth capacity are n necessary to overcome such skewed production pattern and to extend effiectlVe grazmg season l Improved pasture production is an important part of reducing costs in livestock operations and remaining competitive. It is suggested that applying available technology would increase pasture productivity and reduce d$\varepsilon$pendence on stored feeds thus improving profitability of small producers in particeular. Reducing nutrient losses during harv$\varepsilon$stmg, s storage, and feeding is essential for improved production efficiency during confinement. The devclopment of low cost and labor saving methods of ensiling is critical for improved efficiency and profitability of forage based enterprises Livestock industries must respond to consumer preferences for low fat and cholesterol foods. Research and development of entire production systems is emphasized for dev$\varepsilon$loping viabl$\varepsilon$ enterprises. It is increasingly difficult to secure resources for r$\varepsilon$search, education, and extension, and alliane$\varepsilon$s and cooperation must expand among organizations with interests in forage based livestock systems.

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A Case Study on Forecasting Inbound Calls of Motor Insurance Company Using Interactive Data Mining Technique (대화식 데이터 마이닝 기법을 활용한 자동차 보험사의 인입 콜량 예측 사례)

  • Baek, Woong;Kim, Nam-Gyu
    • Journal of Intelligence and Information Systems
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    • v.16 no.3
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    • pp.99-120
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    • 2010
  • Due to the wide spread of customers' frequent access of non face-to-face services, there have been many attempts to improve customer satisfaction using huge amounts of data accumulated throughnon face-to-face channels. Usually, a call center is regarded to be one of the most representative non-faced channels. Therefore, it is important that a call center has enough agents to offer high level customer satisfaction. However, managing too many agents would increase the operational costs of a call center by increasing labor costs. Therefore, predicting and calculating the appropriate size of human resources of a call center is one of the most critical success factors of call center management. For this reason, most call centers are currently establishing a department of WFM(Work Force Management) to estimate the appropriate number of agents and to direct much effort to predict the volume of inbound calls. In real world applications, inbound call prediction is usually performed based on the intuition and experience of a domain expert. In other words, a domain expert usually predicts the volume of calls by calculating the average call of some periods and adjusting the average according tohis/her subjective estimation. However, this kind of approach has radical limitations in that the result of prediction might be strongly affected by the expert's personal experience and competence. It is often the case that a domain expert may predict inbound calls quite differently from anotherif the two experts have mutually different opinions on selecting influential variables and priorities among the variables. Moreover, it is almost impossible to logically clarify the process of expert's subjective prediction. Currently, to overcome the limitations of subjective call prediction, most call centers are adopting a WFMS(Workforce Management System) package in which expert's best practices are systemized. With WFMS, a user can predict the volume of calls by calculating the average call of each day of the week, excluding some eventful days. However, WFMS costs too much capital during the early stage of system establishment. Moreover, it is hard to reflect new information ontothe system when some factors affecting the amount of calls have been changed. In this paper, we attempt to devise a new model for predicting inbound calls that is not only based on theoretical background but also easily applicable to real world applications. Our model was mainly developed by the interactive decision tree technique, one of the most popular techniques in data mining. Therefore, we expect that our model can predict inbound calls automatically based on historical data, and it can utilize expert's domain knowledge during the process of tree construction. To analyze the accuracy of our model, we performed intensive experiments on a real case of one of the largest car insurance companies in Korea. In the case study, the prediction accuracy of the devised two models and traditional WFMS are analyzed with respect to the various error rates allowable. The experiments reveal that our data mining-based two models outperform WFMS in terms of predicting the amount of accident calls and fault calls in most experimental situations examined.

Workplace Friendship and Organizational Effectiveness of Dental Hygienists (치과의료기관 근무자들의 프렌드십과 조직효과성 관계 연구)

  • Yoo, Youngsuk;Seo, Youngjoon;Kim, Sungho
    • Journal of dental hygiene science
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    • v.12 no.6
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    • pp.644-651
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    • 2012
  • This study purports to measure the level of work friendship in dental clinic and examines the friendship's effect on the organizational effectiveness. Data were collected from workers who worked in dental clinic located in Seoul and Gyeonggi areas by self-administered questionnaires from early in October till lately in September, 2009 through direct interview and e-mail. Among 250 questionnaires, 240 responses were returned, and 17 copies with an inaccurate answer were excluded. Finally 223 responses were analyzed through SPSS program. The study revealed that the work friendship in dental clinic has enormous influence on job satisfaction, occupational commitment, intent to leave, stress etc. The results imply that the managers of the dental clinics need to create an organizational climate which emphasizes on a good relationship among members and have them take part in various committees or informal activities.