• Title/Summary/Keyword: 토대 개념

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Analysis of Slope Stability Considering the Saturation Depth Ratio by Rainfall Infiltration in Unsaturated Soil (불포화토 내 강우침투에 따른 포화깊이비를 고려한 사면안정해석)

  • Chae, Byung-Gon;Park, Kyu-Bo;Park, Hyuck-Jin;Choi, Jung-Hae;Kim, Man-Il
    • The Journal of Engineering Geology
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    • v.22 no.3
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    • pp.343-351
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    • 2012
  • This study proposes a modified equation to calculate the factor of safety for an infinite slope considering the saturation depth ratio as a new variable calculated from rainfall infiltration into unsaturated soil. For the proposed equation, this study introduces the concepts of the saturation depth ratio and subsurface flow depth. Analysis of the factor of safety for an infinite slope is conducted by the sequential calculation of the effective upslope contributing area, subsurface flow depth, and the saturation depth ratio based on quasi-dynamic wetness index theory. The calculation process makes it possible to understand changes in the factor of safety and the infiltration behavior of individual rainfall events. This study analyzes stability changes in an infinite slope, considering the saturation depth ratio of soil, based on the proposed equation and the results of soil column tests performed by Park et al. (2011 a). The analysis results show that changes in the factor of safety are dependent on the saturation depth ratio, which reflects the rainfall infiltration into unsaturated weathered gneiss soil. Under continuous rainfall with intensities of 20 and 50 mm/h, the time taken for the factor of safety to decrease to less than 1.3 was 2.86-5.38 hours and 1.34-2.92 hours, respectively; in the case of repeated rainfall events, the time taken was between 3.27 and 5.61 hours. The results demonstrate that it is possible to understand changes in the factor of safety for an infinite slope dependent on the saturation depth ratio.

A Numerical Study of Hydraulic Fractures Propagation with Rock Bridges (Rock bridges를 고려한 수치 해석적 수압파쇄 균열거동 연구)

  • 최성웅
    • Proceedings of the Korean Society for Rock Mechanics Conference
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    • 2000.09a
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    • pp.201-210
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    • 2000
  • Rock bridge in rock masses can be considered as one of several types of opening-mode fractures, and also it has been known to have a great influence on the stability of structures in rock mats. In the beginning of researching a rock bridge it used to be studied only in characteristics of its behavior, as considering resistance of material itself. However the distribution pattern of rock bridges, which can affect the stability of rock structures, is currently researched with a fracture mechanical approach in numerical studies. For investigating the effect of rock bridges on the development pattern of hydraulic fractures, the author analyzed numerically the stress state transition in rock bridges and their phenomena with a different pattern of the rock bridge distributons. From the numerical studies, a two-crack configuration could be defined to be representative of the most critical conditions for rock bridges, only when cracks are systematic and same in their length and angle. Moreover, coalescence stresses and onset of propagation stresses could be known to increase with decreasing s/L ratio or increasing d/L ratio. The effect of pre-existing crack on hydraulic fracturing was studied also in numerical models. Different to the simple hydraulic fracturing modeling in which the fractures propagated exactly parallel to the maximum remote stress, the hydraulic fractures with pre-existing cracks dial not propagate parallel to the maximum remote stress direction. These are representative of the tendency to change the hydraulic fractures direction because of the existence of pre-existing crack. Therefore s/L, d/L ratios will be identical as a function effective on hydraulic fractures propagation, that is, the $K_{I}$ vague increase with decreasing s/L ratio or increasing d/L ratio and its magnification from onset to propagation increases with decreasing s/L ratio. The scanline is a commonly used method to estimate the fracture distribution on outcrops. The data obtained from the scanline method can be applied to the evaluation of stress field in rock mass.s.

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A Numerical Study of Hydraulic Fractures Propagation with Rock Bridges (Rock bridges를 고려한 수치 해석적 수압파쇄 균열거동 연구)

  • 최성웅
    • Tunnel and Underground Space
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    • v.10 no.3
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    • pp.447-456
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    • 2000
  • Rock bridge in rock masses can be considered as one of several types of opening-mode fractures, and also it has been known to have a great influence on the stability of structures in rock mass. In the beginning of researching a rock bridge it used to be studied only in characteristics of its behavior, as considering resistance of material itself. However the distribution pattern of rock bridges, which can affect the stability of rock structures, is currently researched with a fracture mechanical approach in numerical studies. For investigating the effect of rock bridges on the development pattern of hydraulic fractures, the author analyzed numerically the stress state transition in rock bridges and their phenomena with a different pattern of the rock bridge distributions. From the numerical studies, a two-crack configuration could be defined to be representative of the most critical conditions for rock bridges, only when cracks are systematic and same in their length and angle. Moreover, coalescence stresses and onset of propagation stresses could be known to increase with decreasing s/L ratio or increasing d/L ratio. The effect of pre-existing crack on hydraulic fracturing was studied also in numerical models. Different to the simple hydraulic fracturing modeling in which the fractures propagated exactly parallel to the maximum remote stress, the hydraulic fractures with pre-existing cracks did not propagate parallel to the maximum remote stress direction. These are representative of the tendency to change the hydraulic fractures direction because of the existence of pre-existing crack. Therefore s/L, d/L ratios will be identical as a function effective on hydraulic fractures propagation, that is, the K$_1$ value increase with decreasing s/L ratio or increasing d/L ratio and its magnification from onset to propagation increases with decreasing s/L ratio. The scanline is a commonly used method to estimate the fracture distribution on outcrops. The data obtained from the scanline method can be applied to the evaluation of stress field in rock mass.

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A Study on the Improvement of the Existing Technology Valuation Solutions;focused on high technology based start-up company (현행 기술가치 평가모형의 개선 방안에 관한 연구;신기술 창업기업의 경우를 중심으로)

  • Yang, Tai-Shik;Min, Kyung-Se
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.2 no.2
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    • pp.93-120
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    • 2007
  • To promote the commercialization of high technology based start-up company, it is essential to activate technology trading for the Innovative Small & Medium companies which eager to acquire technology competitiveness through technology trading and facilitate financial system which provide Small & Medium companies with technology commercialization money. This study focus on enhancing credibility of technology valuation solutions through the improvement of the existing technology valuation solutions. The existing technology valuation solutions in practice have deficiency in reasonable valuation because of subjective technology factor's calculation. And the commercialization risk of high technology based start-up companies cannot be fully reflected in the existing valuation solutions. The high risk of technology commercialization acts as a hurdle in the facilitation of providing money for the start-up companies. The improved new model will have more acceptable objectivity and reasonably reflect the commercialization risk of start-up companies. The new model has two distinctive features compared to existing solutions. The new model newly adopts commercialization success factor which reflects the risk of high technology based start-up company. And the new model excludes technology factor which is controversial among interested parties. The exclusion of technology factor will improve the objectivity of technology valuation and the adoption of commercialization success factor will solicit investor and capitalist who concern the high risk of technology based start-up companies. In conclusion, the improved new model is expected to activate technology trading and facilitate the money market through which high technology based start-up companies raise commercialization money.

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A Study on the Location of Zen Buddhist Temples During the Late Silla Dynasty in Korea - from Feng-shui(風水) Perspective - (신라말 구산선문(九山禪門) 사찰의 입지 연구 - 풍수적 측면을 중심으로 -)

  • Cho, Sung-Ho;Sung, Dong-Hwan
    • Journal of the Korean association of regional geographers
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    • v.6 no.3
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    • pp.53-81
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    • 2000
  • The purpose of this study is to examine the chracteristics of the location of Zen Buddhist temples which are the Nine-Mountain Sects of Zen(九山禪門) from feng-shui perspective. A large number of temples have been built for about 1600 years since Buddhism had influenced on Korea. They have been built nationwide in different times by different sects of Buddhism. The pattern of location of Buddhist temples is different according to background of the times (political, economic, cultural aspect) and of tenet(difference in sects of Buddhism) when the temples were built. But the general location of Korean Buddhist temples is in accordance with feng-shui theory. Feng-shui is a traditional geographic thought in China and Korea. It is necessary to understand feng-shui in order to understand Korean landscape and cultural geography. It had given a tremendous impact on Korean landscape through choosing site of cities, settlements, houses, mounments, temples, pagodas, and so on. Before feng-shui was prevailing in Korea, Buddhist temples were mostly built on sacred place which was connected with folk beliefs. In the case of the late Silla Dynasty when Zen Buddhism was prevailing, feng-shui became popular and many. temples were built in accordance with feng-shui. The typical examples are found in the site of Nine-Mountain Sects of Zen temples. The interpretation of geomantic site of Nine-Mountain Sects of Zen temples will show us how feng-shui was applied to and reflected in the Korean peninsula. In Zen Buddhism, feng-shui was applied to the choice of the temple site. Also feng-shui theory was usually used to choose the site of stupa(Budo) where the remains of the founder of sect. In this study, I will interpret the geomantic characteristics of Nine-Mountain Sects of Zen temples. The geomantic interpretations of the temples are as follow. 1. The temples are located at the foot of a hill with surrounding mountains and a watercourse in front. Feng-shui texts often describe it as an ideal site. This geomantic situation is well equipped with natural drainage; protection from cold wind from the north or evil spirits; a good view with open space to the front; protection from unnecessary weather damage; and security and protection from strangers and invaders. 2. The sitting and facing direction of the temples correspond to the oncoming dragon's direction. 3. Many feng-shui texts discuss the types of Sa(surrounding mountains) in detail and morphologically describe them with certain animate and inanimate auspicious objects. In case of Nine-Mountain Sects of Zen temples, the geomantic landscape of these can be compared to auspicious objects. This is morphological marker for the description of configulation features of these temples. 4. Most auspicious places are not perfect, but the shortcomings can be overcome by many means. We can observe modification of landscape for the purpose of fulfilling the geomantic harmony of the temple.

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Homeland Security Management: A Critical Review of Civil Protection Mechanism in Korea (국가안전관리: 한국의 시민보호(위기재난관리) 체계에 관한 비판적 고찰)

  • Kim, Hak-Kyong
    • Korean Security Journal
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    • no.26
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    • pp.121-144
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    • 2011
  • The Framework Act on the Management of Disasters and Safety 2004(FAMDS) currently underpins Korean civil protection system, and under this FAMDS, Korean civil protection establishes a three-tiered government structure for dealing with crises and disasters: central government, provincial & metropolitan government, and local government tiers. In particular, the concept of Integrated Emergency Management(IEM) emphasizes that emergency response organizations should work and act together to respond to crises and disasters effectively, based on the coordination and cooperation model, not the command and control model. In tune with this trend, civil protection matters are, first, dealt with by local responders at the local level without direct involvement of central or federal government in the UK or USA. In other words, central government intervention is usually implemented in the UK and the USA, only when the scale or complexity of a civil protection issue is so vast, and thus requires a degree of central government coordination and support, resting on the severity and impact of the event. In contrast, it appears that civil protection mechanism in Korea has adopted a rigid centralized system within the command and control model, and for this reason, central government can easily interfere with regional or local command and control arrangements; there is a high level of central government decision-making remote from a local area. The principle of subsidiarity tends to be ignored. Under these circumstances, it is questionable whether such top-down arrangements of civil protection in Korea can manage uncertainty, unfamiliarity and unexpectedness in the age of Risk Society and Post-modern society, where interactive complexity is increasingly growing. In this context, the study argues that Korean civil protection system should move towards the decentralized model, based on coordination and cooperation between responding organizations, loosening the command and control structure, as with the UK or the USA emergency management arrangements. For this argument, the study basically explores mechanisms of civil protection arrangements in Korea under current legislation, and then finally attempts to make theoretical suggestions for the future of the Korean civil protection system.

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Study on Reduction Effect of the Non-Point Pollutants through Riparian Buffer Zones (비점오염부하 저감을 위한 수변완충지대의 효율적 조성 연구)

  • Choi, I-Song;Kim, Sung-Won;Jung, Sang-Jun;Woo, Hyo-Seop;Oh, Jong-Min
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.1793-1797
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    • 2007
  • 한강 "수변구역"에서 비점오염물질의 공공수역 유입을 억제하기 위한 다양한 방법들 중에서 보편적이고 자연친화적인 방법은 다양한 생물의 서식공간이며, 동시에 본류로 유입되는 과정에서 수질을 정화시키는 수질개선 공간인 수변완충구역, 또는 지대를 설정하여 관리하는 것이다. 그러나 이러한 수변완충지대 효과 분석 및 설정에 관한 연구는 국내에서 아직 수행되지 않았다. 본 연구의 목적은 수변구역의 자정능력을 높이는 것은 물론 그 밖의 하천 연안에서 비점오염물질의 차단과 처리능력을 증진시키고 수변 생태계의 서식처 보전 및 복원을 위해서 수변완충지대의 수질정화 기술개발과 생물다양성을 창출하는 수변완충지대 조성 기법을 개발하는데 있다. 본 연구에서는 기존 수변완충지의 추가적인 조성과 보완, 시험완충지 생태구조 및 기능 기초조사, 시험완충지 오염부하 저감효과의 실험 및 분석, 수변완충지대 설치 구상 등의 연구를 수행하였다. 수행 지역은 한강수계 지역으로 남한강 수변인 경기도 양평군 병산리에서 실시하였으며, 잔디와 갈대, 갯버들, 혼합지역, 자연그대로의 상태(대조지역)의 5 구역으로 구분하였고, 깊이별로 샘플을 채취하여 유입수와 표면유출, 하부유출을 비교해 보았다. 연구 결과, 5 가지 구역 중 잔디 구역의 SS, T-N, T-P, TOC의 제거 효율이 각각 76.7%, 85.2%, 97.6%, 83.3%로 가장 좋은 오염물질 제거 효율을 보였으며, 깊이 별 분석에서는 표면유출에서 하부유출로 갈수록 월등한 효율을 보였다. 따라서 본 연구를 통하여 비점오염원에 대한 한강수계의 수자원 보호 효과를 기대할 수 있고, 수변완충지대의 조성, 유지관리기술의 개발을 통한 수변완충지대의 계획과 설계에 직접적인 기여를 할 수 있으며, 수변구역에 설치 가능한 Riparian Buffer Zone의 중요성과 효율성을 알려 현재 하상 저니 준설 및 폭기 위주의 사업에서 생태 공학적 복원을 적극 고려한 정화사업으로 확대 추진하고자 한다.해결책을 얻어내는 상호보완적인 결과를 추구한다. 그가 디자인하는 작품은 전형적인 이미지를 내포하지 않는다. 즉 그의 작품은 기존의 가치와 이념적인 것은 배제하고, 창의적인 개념을 도출하였다.형모서리는 건물 특화 성격이 강하므로 불가피할 경우 소형 액센트 광고 위치를 미리 벽면으로 할애하는 것이 경관 및 입면계획에 유리한 것으로 분석되었다. 불확실도 해석모형 등의 새로운 기능을 추가하여 제시하였다. 모든 입출력자료는 프로젝트 단위별로 운영되어 data의 관리가 손쉽도록 하였으며 결과를 DB에 저장하여 다른 모형에서도 적용할 수 있도록 하였다. 그리고 HyGIS-HMS 및 HyGIS-RAS 모형에서 강우-유출-하도 수리해석-범람해석 등이 일괄되게 하나의 시스템 내에서 구현될 수 있도록 하였다. 따라서 HyGIS와 통합된 수리, 수문모형은 국내 하천 및 유역에 적합한 시스템으로서 향후 HydroInformatics 구현을 염두에 둔 특화된 국내 수자원 분야 소프트웨어의 개발에 기본 토대를 제공할 것으로 판단된다.았다. 또한 저자들의 임상병리학적 연구결과가 다른 문헌에서 보고된 소아 신증후군의 연구결과와 큰 차이를 보이지 않음을 알 수 있었다. 자극에 차이가 있지 않나 추측되며 이에 관한 추후 연구가 요망된다. 총대장통과시간의 단축은 결장 분절 모두에서 줄어들어 나타났으나 좌측결장 통과시간의 감소 및 이로 인한 이 부위의 통과시간 비율의 저하가 가장 주요하였다. 이러한 결과는 차가운 생수 섭취가 주로 결장 근위부를 자극하는 효과를 발휘하는 것이 아닌가 해석된다. 이와 같은 연구결과를 통해 생다시마를 주원료로 개발된 생다시마차와 생다시마 음료가 만성 기능성 변비 증세를 개선하는 효능이 잠재적으로 있음을 확인하였다. 그러나 생약제재의 변비약 수준으로 변비 개선 효능을 증대하기 위해서는 재료 배합비의 개선이나 대장 운동기능을 향상시키는 유효성분의 보강 등이 필요하다는 점도 알 수 있었다.더불어 산화물질 해독에 관여하는

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The Effects of Self-esteem, Relationships with Parents and Peer Relationships on Adolescents' School Adjustment (청소년의 자아존중감, 부모와의 관계, 친구관계가 학교생활적응에 미치는 영향)

  • Lim, Soo-Kyoung;Lee, Hyong-Sil
    • Journal of Korean Home Economics Education Association
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    • v.19 no.3
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    • pp.169-183
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    • 2007
  • The purpose of this study is to examine the effects of self-esteem, relationships with parents and peer relationships on adolescents' school adjustment. Total of 900 middle school students residing in Guri, Geonggi-Do participated in the survey and the data collected from 874 students (557 male and 317 female students) were analyzed for this study. The followings summarize results of the study. First, the findings suggested that there is no significant difference between female and male students in school adjustment. Secondly, the study revealed that there is no difference between female and male students in self-esteem and relationship with parents. Thirdly, this study provided clear evidence that students with high self-esteem and close relationship with parents and schoolmates adapt to school life better than those with low self-esteem and distant relationship with parents and schoolmates. Fourthly, students with high self-esteem and close relationship with parents and schoolmates displayed higher adaptability to school life, and as for male students, close relationship with schoolmates was the most prominent factor which helps them adapt to school life better while female students' adaptability to school lifewas mainly affected by relationship with parents.

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CEO's Political Independence, Board Chair Separation, Executive's Expertise, and Performance in State-Owned Enterprises (공기업 CEO의 정치적 독립성, 이사회 의장 분리, 임원의 전문성과 성과)

  • Yu, Seungwon
    • KDI Journal of Economic Policy
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    • v.35 no.2
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    • pp.1-39
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    • 2013
  • Considering the relationship between state-owned enterprise (SOE) CEOs and political circles, this study examines the performance impacts of CEO's succession type, board chair separation, and industry expertise and finance expertise of CEOs and outside directors. I propose the definition of political independence in SOE CEOs based on the independence in appearance that might affect general people's perception. It means that there are no relationships or circumstances that might affect SOE CEO's judgment, activity, and report. The definition is able to overcome the limitations of the prior research that could not discover the CEOs who were affiliated to political circles because the research just distinguished the CEOs following their pre-jobs. This study focused on the performance impacts of political independence impaired CEO as well as the CEO's impacts on the relationship between the performance and other corporate governance variables. I selected as dependent variables the average return on asset as operating income divided by total assets and the average customer satisfaction rate evaluated by Korean government during the first three years following the year of the events of explanatory variables. My theory and evidence from the various CEO's personal background and financial information from SOEs in Lee Myung-bak Administration and Rho Moo-hyun Administration suggest the following important things. First, the analysis based on whether or not a SOE CEO keeps political independence shows that a political independence impaired CEO made a significantly negative impact on customer satisfaction rate. Second, the separation between a board chair and a CEO in SOEs introduced by Korean Act on Management of Public Institutions made a significantly positive impact on customer satisfaction rate. However, the positive impact of the board chair separation was removed in a political independence impaired CEO's SOE. Third, outside director's industry expertise made a significantly positive impact on return on asset. However, the positive impact of the outside director's industry expertise was removed in a political independence impaired CEO's SOE. Fourth, the comparison between Lee Myung-bak Administration and Roh Moo-hyun Administration on the corporate governance and performance of SOEs shows that the ratio of political independence impaired CEO was significantly higher in Lee Administration and the ratio of outside director's industry expertise and finance expertise were respectively significantly higher in Roh Administration. Based on these results, I suggested a few policy alternatives for CEO's improved political independence and requirements for executive's expertise in SOEs.

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An Exploratory Study on Measuring Brand Image from a Network Perspective (네트워크 관점에서 바라본 브랜드 이미지 측정에 대한 탐색적 연구)

  • Jung, Sangyoon;Chang, Jung Ah;Rho, Sangkyu
    • The Journal of Society for e-Business Studies
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    • v.25 no.4
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    • pp.33-60
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    • 2020
  • Along with the rapid advance in internet technologies, ubiquitous mobile device usage has enabled consumers to access real-time information and increased interaction with others through various social media. Consumers can now get information more easily when making purchase decisions, and these changes are affecting the brand landscape. In a digitally connected world, brand image is not communicated to the consumers one-sidedly. Rather, with consumers' growing influence, it is a result of co-creation where consumers have an active role in building brand image. This explains a reality where people no longer purchase products just because they know the brand or because it is a famous brand. However, there has been little discussion on the matter, and many practitioners still rely on the traditional measures of brand indicators. The goal of this research is to present the limitations of traditional definition and measurement of brand and brand image, and propose a more direct and adequate measure that reflects the nature of a connected world. Inspired by the proverb, "A man is known by the company he keeps," the proposed measurement offers insight to the position of brand (or brand image) through co-purchased product networks. This paper suggests a framework of network analysis that clusters brands of cosmetics by the frequency of other products purchased together. This is done by analyzing product networks of a brand extracted from actual purchase data on Amazon.com. This is a more direct approach, compared to past measures where consumers' intention or cognitive aspects are examined through survey. The practical implication is that our research attempts to close the gap between brand indicators and actual purchase behavior. From a theoretical standpoint, this paper extends the traditional conceptualization of brand image to a network perspective that reflects the nature of a digitally connected society.