• Title/Summary/Keyword: Top Down Method

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Assessment of Applicability of Pretentioned Soil-Nail Systems with in-situ monitoring (현장 계측을 통한 프리텐션 쏘일네일링 시스템의 적용성 평가)

  • Lee, Hyuk-Jin;Ahn, Kwang-Kuk;Kim, Hong-Taek;Bang, Yoon-Kyung
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.10a
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    • pp.320-329
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    • 2005
  • The use of diverse methods for the retaining system has been continuously increased in order to maintain the stability during excavation. However, ground anchor system occasionally may have the restriction in urban excavation sites nearby the existing structures because of space limitation. In this case, soil nailing system with relatively short length of nails could be efficiently useful as an alternative method. The general soil nailing support system, however, may result in excessive deformations particularly in excavating the zone of weak soils or nearby the existing structures. Therefore, applying the pretension force to the soil nails then could play important roles to reduce deformations mainly in an upper part of the nailed-soil excavation system as well as to improve the local slope stability. In this study, a newly modified soil nailing technology named as the PSN(Pretention Soil Nailing) is developed to reduce both facing displacements and ground surface settlements during top-down excavation process as well as to increase the global slope stability. Up to now, the PSN system has been investigated mainly focusing on an establishment of the design procedure. In the present study, the field tests including pull-out tests were fulfilled to investigate the behavior of characteristics for PSN system. All results of tests were also analyzed to provide a fundamental and efficient design.

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A Study to Determine the Degree of Difficulties with the Excavation of Corestone Weathering Profiles (핵석지반에서의 굴착난이도 평가방법 연구)

  • Lee, Su-Gon;Lee, Byok-Kyu;Kim, Min-Sung
    • The Journal of Engineering Geology
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    • v.17 no.1 s.50
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    • pp.89-99
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    • 2007
  • This paper intends to introduce more objective and qualitative rock mass classification method easily applicable to the excavation of gneissic masses showing corestone weathering profiles. It is proven that corestone weathering profile could be divided with reasonable accuracy into digging, ripping and blasting layers using visual and simple mechanical techniques such as Schmidt hammer rebound test on cut slopes, taking into consideration strength and spacial distribution of corestone, workability and work efficiency of excavation. Also, seismic refraction surveys were employed for shallow investigations (down to $20{\sim}30m$ depth) in corestone weathering profile and conducted across the top of vertical exposures where the underlying geology could be directly inspected. Some discrepancies ($3{\sim}4m$ in average and 6 m occasionally) between the actual and assumed materials with respect to seismic velocities were observed. Thus it can be concluded that field geotechnical mapping and field seismic test should be used together in order to get a relatively good accuracy in assessing likely excavation conditions of corestone weather-ing profiles.

The Factors Affecting the Driving Experience based on UX (UX기반의 운전 경험에 영향을 미치는 요소)

  • Park, Do Eun;Yoon, Ye Jin;Park, Su E
    • The Journal of the Korea Contents Association
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    • v.17 no.4
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    • pp.237-246
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    • 2017
  • Recently, with the attention of future vehicle technology, automobiles that are influenced by user experience(UX) are regarded as living space. However, the concept of term, definition, and constituent factors of driving experience have not been established so far. The purposes of this study are to define driving experience in terms of UX and to extract experience factors. We conducted the 18 drivers interviews and studied literature reviews. The collected interview data was analyzed by bottom-up method based on the grounded theory. And we reconstructed it through the top-down approach, based on the results of the literature review. As the result, the 'driving experience' is a concept that means all the emotions, perceptions, and cognitive outcomes on the basis of personal characteristics that drivers have in anticipation of the driving situation from the start to the destination Respectively. Nine factors that constitute driving experience were extracted by 'internal UI factors', 'environmental factors' and 'user related factors'.

Application of 3D Chain Code for Object Recognition and Analysis (객체인식과 분석을 위한 3D 체인코드의 적용)

  • Park, So-Young;Lee, Dong-Cheon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.29 no.5
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    • pp.459-469
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    • 2011
  • There are various factors for determining object shape, such as size, slope and its direction, curvature, length, surface, angles between lines or planes, distribution of the model key points, and so on. Most of the object description and recognition methods are for the 2D space not for the 3D object space where the objects actually exist. In this study, 3D chain code operator, which is basically extension of 2D chain code, was proposed for object description and analysis in 3D space. Results show that the sequence of the 3D chain codes could be basis of a top-down approach for object recognition and modeling. In addition, the proposed method could be applicable to segment point cloud data such as LiDAR data.

A study on Mapping the Unicode based Hangul-Hanja for prescription names in Korean Medicine (처방명 연계를 위한 유니코드 한자 기반의 한글-한자 매핑정보 구축에 관한 연구)

  • Jeon, Byoung-Uk;Kim, An-Na;Kim, Ji-Young;Oh, Yong-Taek;Kim, Chul;Song, Mi-Young;Jang, Hyun-Chul
    • Korean Journal of Oriental Medicine
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    • v.18 no.3
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    • pp.133-139
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    • 2012
  • Objective : UMLS is 'Ontology' which establishes the database for medical terminology by gathering various medical vocabularies representing same fundamental concepts. Method : Although Chinese character are represented in the Chinese part of Korean Unicode system in a computer, writing of Chinese characters is vary depending on Chinese input systems and Chinese writers' levels of knowledge. As the result of this, representation of Chinese writing in a computer will be considerably different from an old Chinese document. Therefore, a meaningful relationship between digital Chinese terminology and translated Korean is necessary in order to build Ontology for Chinese medical terms from Oriental medical prescription in a computer system. Result : This research will present 1:1 mapping information among the Chinese characters used in the Oriental medical prescription with analysis of 'same character different sound' and 'same meaning different shape' in Chinese part of Unicode systems. Conclusions : Furthermore, the research will provide top-down menu of relationship between Chinese term and Korean term in medical prescription with assumption of that the Oriental medical prescription has its own unique meaning.

Effects of content and formal schema on reading comprehension (내용과 형식 스키마가 독해에 미치는 영향)

  • Yeon, Jun-Hum
    • English Language & Literature Teaching
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    • no.3
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    • pp.95-122
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    • 1997
  • The purpose of this research was to investigate the effects of content and formal schema on reading comprehension. Five hundred fiftynine subjects from high school were assigned to one of the following levels and treatment conditions : (1) Higher level & Schema Activation, (2) Higher level & Non-schema Activation, (3) Lower level & Schema Activation, and (4) Lower level & Non-schema Activation. To evaluate the effects of schema activation. two experiments were conducted : one was related to the content schema and the other to the formal schema. To evaluate the effects of content schema, three different types of tests were conducted : (1) cloze test, (2) guessing the meanings of nonsense words, and (3) immediate recall test. To evaluate the effects of formal schema instruction, four kinds of tests were conducted : (1) sorting the sentences according to the importance, (2) identifying the signal words, (3) immediate recall test, and (4) identifying the specific information. For content schema condition, results indicated that the subjects given the titles or pictures before reading in "Content Schema Activation" treatment had better grades than those of the other treatment in all types of tests. regardless of their levels. Schema activation helped the subjects to increase the cognitive predictability of missing words and to participate in the tasks more actively with risk-taking. And it was also shown that good readers tend to process the words meaningfully, while poor readers tend to process the words phonetically or morphologically. Formal schema activation through teaching the text organization also had a significant influence on three types of tests: sorting the sentences according to the importance, identifying the signal words, and immediate recall test, but not on identifying the specific information. The implications from this study can be briefly noted as follows : (l) In teaching reading, the student's background knowledge should be activated as a pre-reading activity. (2) In reading, it is more important to emphasize the student's schema than the features of the text. (3) Various educational interventions should be introduced, especially for the lower level students. (4) Teaching text structures can be a powerful method for the top-down processing strategy.

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Estimation of polycyclic aromatic hydrocarbons emission from sewage sludge of sewerage treatment plants in Korea

  • Kim, Dong-Hwan;Hwang, Jong-Seob;Lee, Min-Hee;Ok, Gon
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2003.11a
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    • pp.85-88
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    • 2003
  • Polycyclic aromatic hydrocarbons (PARs) are an important group of organic contaminants present in sewage sludge, due to their persistence, toxic, bioaccumulative and long range transfer. These characters make themselves as Persistent Organic Pollutants(POPs) in Long Range Transboundary Air Pollutions convention(LRT AP) of Europe. A method of the gas chromatographic-mass spectrometric (GC-MS) determination of PARs present in sewage sludge was developed and applied to analyzed samples from five sewerage treatment plants (SWTPs), having different treatment types. PARs were extracted from freeze-dried samples by toluene 16 hours in a soxhlet extraction system. The sludge extracts were cleaned-up by an activated silica gel column chromatography. The sum of the 16 US Environmental Protection Agency PARs sewage sludge samples varied from 2.44 to 4.82 ${\mu}g$/g. Concentration of emission carcinogen PARs(PARcarc), such as Benzo(a)anthracene, Benzo(b)fluoranthene, Benzo(k)fluoranthene, Benzo(a)pyrene, Dibenzo(a, h)anthracene and Indeno(1, 2, 3-cd)pyrene ranged from 0.62 to 1.03 ${\mu}g$/g. The total amount of PAHs emission from sewage sludge in Korea was calculated as a top-down approach. PARs and $\sum$PAHcarc from sewage treatment plants had several pathway each by-products. In the ocean dumping, PAHs and $\sum$PAHcarc emissions were 1155.95 kg/year and 5040.32 kg/year. In recycle, PAHs and $\sum$PAHcarc emissions were 98.36 kg/year and 428.87 kg/year. In the landfill, PAHs and $\sum$PAHcarc emissions were 190.40 kg/year and 830.21 kg/year. In the incineration, PAHs and $\sum$PAHcarc emission were 33.10 kg/year and 830.21 kg/year. (In case of incineration, the whole provisions of PARs and $\sum$PAHcarc contained to flowed in sludge was supposed to be exhausted to environment through exhaust after incineration.)

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A Study on Women's Underwear Structures by Ideal Beauty - Focused on the Former Period of 20th Century - (이상미에 따른 여성 속옷 구성에 관한 연구(1) - 20세기 전기를 중심으로-)

  • 김지연;전혜정
    • Journal of the Korean Society of Costume
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    • v.53 no.3
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    • pp.137-154
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    • 2003
  • The purpose of this study is firstly to survey the social and cultural background of 20th century and women's status, and to identify what the ideal body is like and what the elements of outer garment and underwear are and the techniques to incarnate the ideal beauty. Various papers are referenced for theoretical study and the elements and techniques of underwear are analyzed based on photographical materials. This paper concludes as follows. In 1910's, ideal beauty has changed to H-style. In other words, the outer garment has confined the lower part of the body with plain H-type Hobble silhouette to express plump bust, somewhat slim waist, and small hips, As the underwears, cylindrical corsets which fasten from under the bust down to lap, brassiere which are helpful for plump bust, and artificial busts were worn. In 1920's, outer garment were Straight box silhouette style which were cut as tubular without dart, and the underwears were corselets which have been tubular from the bust to hip and the tubular chemi-knickers. The former corsets which had been hard-boned and been fastened with strings have been replaced by the hook closure due to the development of elastic joining method. In 1930's, women pursued perfect body showing the line of bust, waist, and hip. In order to express elegant beauty of female of Slim and long silhouette, Doter and underwear have been cut with bias and gore, and soft and flexible materials were flowed along the body. World war II in 1940's has made the women as social. Ideal beauty has changed to Short straight box silhouette which no more shows body line. Outer and underwears were simple and Practical style. In 1950's, ideal beauty was well-matured, elegant Women which were represented by round shoulder, conical breast, tiny waist and round hip. Outer garment showed Hourglass silhouette representing the body-tight suits with round shoulder pad and the wide flare skirts. As the underwears, conical brassiere by top circular stitch were preferred for plump and bulged bust and tight corsets for tiny waist and magnificent petticoats were worn.

A study on Methodology for Street Furniture Improvement with Space Syntax (공간구문론을 이용한 농촌마을 가로환경시설 정비 방안)

  • Kwon, Soon Chan;Lim, Chang Su;Kim, Eun Ja;Oh, Yun Kyung;Yoon, Gi Eun;Choi, Jin Ah
    • Journal of Korean Society of Rural Planning
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    • v.21 no.1
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    • pp.29-39
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    • 2015
  • In farming area, the elderly population is increasing year after year. And the gap between farming area and the city regarding quality of life is getting bigger and bigger. Besides, it has much poorer ground for living than the city. The current farming village maintenance project is adopting a different system now from the top-down project exclusively led by the government in the past to the bottom-up one reflecting how the residents think positively. Lack of the residents' understanding and education about the maintenance project, however, some of them are just focused on maintenance and development distorted from making a village where people want to live. Accordingly, this study will analyze the characteristics of farming villages by their types based on field research and spatial analysis using Space Syntax in order to develop more premeditated and effective maintenance plans to perform maintenance in farming area. As a result, When you install streetlights street lights should be installed at places with a high of Connectivity and spatial depth is deep. Based on this method, the research is going to suggest the current status of street furniture improvement in the villages and the proper positions for their future installation.

Evaluation on Radioactive Waste Disposal Amount of Kori Unit 1 Reactor Vessel Considering Cutting and Packaging Methods (고리 1호기 원자로 압력용기 절단과 포장 방법에 따른 처분 물량 산정)

  • Choi, Yujeong;Lee, Seong-Cheol;Kim, Chang-Lak
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.14 no.2
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    • pp.123-134
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    • 2016
  • Decommissioning of nuclear power plants has become a big issue in South Korea as some of the nuclear power plants in operation including Kori unit 1 and Wolsung unit 1 are getting old. Recently, Wolsung unit 1 received permission to continue operation while Kori unit 1 will shut down permanently in June 2017. With the consideration of segmentation method and disposal containers, this paper evaluated final disposal amount of radioactive waste generated from decommissioning of the reactor pressure vessel in Kori unit 1 which will be decommissioned as the first in South Korea. The evaluation results indicated that the final disposal amount from the top and bottom heads of the reactor pressure vessel with hemisphere shape decreased as they were cut in smaller more effectively than the cylindrical part of the reactor pressure vessel. It was also investigated that 200 L and 320 L radioactive waste disposal containers used in Kyung-Ju disposal facility had low payload efficiency because of loading weight limitation.