• Title/Summary/Keyword: 확산 효율

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Information technology and changes in firm activities:A case of the service industry in the United States (정보기술과 기업활동의 변화:미국의 서비스산업을 사례로)

  • Lee, Jeong Rock
    • Journal of the Korean Geographical Society
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    • v.29 no.4
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    • pp.402-419
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    • 1994
  • Telecommunication and intormation technology have been conceived as crucial as well as revolutionary elements for recent and future social and economic development, and their development have led to a spatial reorganization and locational change of economic activities. Information technology has resulted in important changes in the organization structure and location of firm. This study draws attention to the understanding of the relationship between the diffusion of information technology and changes in firm activities with the special reference to the service industry of the United States. Information technology has had a significant impact on the growth and changes of the service industry of the United States through changes in the organizational and employment structure, market structure, and locational changes. The impact of information technology on location changes of the service industry shows two opposite patterns, concentration and decentralization. Among these patterns, the location change in the service industry of the United States reveals predominantly the decentralization tendency such as suburbanization and transfer to lower ranking cities rather than concentration. In case of Korea, however, it is anticipated that the rapid development of information technology may lead to the concentration of the service industry in Seoul and Capital region.

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Improvement of Cu2ZnSnS4 Solar Cell Characteristics with Zn(Ox,S1-x) Buffer Layer (Zn(Ox,S1-x) 버퍼층 적용을 통한 Cu2ZnSnS4 태양전지 특성 향상)

  • Yang, Kee-Jeong;Sim, Jun-Hyoung;Son, Dae-Ho;Lee, Sang-Ju;Kim, Young-Ill;Yoon, Do-Young
    • Korean Chemical Engineering Research
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    • v.55 no.1
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    • pp.93-98
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    • 2017
  • This experiment investigated characteristic changes in a $Cu_2ZnSnS_4$(CZTS) solar cell by applying a $Zn(O_x,S_{1-x})$ butter layer with various compositions on the upper side of the absorber layer. Among the four single layers such as $Zn(O_{0.76},S_{0.24})$, $Zn(O_{0.56},S_{0.44})$, $Zn(O_{0.33},S_{0.67})$, and $Zn(O_{0.17},S_{0.83})$, the $Zn(O_{0.76},S_{0.24})$ buffer layer was applied to the device due to its bandgap structure for suppressing electron-hole recombination. In the application of the $Zn(O_{0.76},S_{0.24})$ buffer layer to the device, the buffer layer in the device showed the composition of $Zn(O_{0.7},S_{0.3})$ because S diffused into the buffer layer from the absorber layer. The $Zn(O_{0.7},S_{0.3})$ buffer layer, having a lower energy level ($E_V$) than a CdS buffer layer, improved the $J_{SC}$ and $V_{OC}$ characteristics of the CZTS solar cell because the $Zn(O_{0.7},S_{0.3})$ buffer layer effectively suppressed electron-hole recombination. A substitution of the CdS buffer layer by the $Zn(O_{0.7},S_{0.3})$ buffer layer improved the efficiency of the CZTS solar cell from 2.75% to 4.86%.

Effects of Sodium and Gallium on Characteristics of CIGS Thin Films and CdS/CIGS Solar Cells by Co-evaporation Method (Na확산과 Ga첨가에 따른 동시진공증발법으로 제조된 CIGS 박막과 CdS/CIGS 태양전지의 특성)

  • Kwon, S.H.;Lee, J.C.;Kang, K.H.;Kim, S.K.;Yoon, K.H.;Song, J.S.;Lee, D.Y.;Ahn, B.T.
    • Solar Energy
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    • v.20 no.2
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    • pp.43-54
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    • 2000
  • We prepared and characterized $Cu(In_{1-x}Ga_x)Se_2$(CIGS) films using a elemental co-evaporation method for absorbing layer of high efficiency thin film solar cells. The CIGS films deposited on a soda-lime glass exhibited low resistivity because of higher carrier concentration. Na was accumulated at the CIGS surface and the 0 and Se were also accumulated at the surface, suggesting that oxidation is a driving force of Na accumulation. The structure of CIGS film was modified or a secondary phase was formed in the Cu-poor CIGS bulk films probably due to the incorporation of Na into Cu vacancy sites. As the Ga/(In+Ga) ratio increased, the diffraction peaks of $Cu(In_{1-x}Ga_x)Se_2$ films were shifted to larger angle and splitted, and the grain size of $Cu_{0.91}(In_{1-x}Ga_x)Se_2$ films became smaller. All $Cu_{0.91}(In_{1-x}Ga_x)Se_2$ films showed the p-type conductivity regardless of the Ga/(In+Ga) ratio. Ag/n-ZnO/i-ZnO/CdS/$Cu_{0.91}(In_{0.7}Ga_{0.3})Se_2$/Mo solar cells were fabricated. The currently best efficiency in this study was 14.48% for $0.18cm^2$ area ($V_{oc}=581.5mV,\;J_{sc}=34.88mA$, F.F=0.714).

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Difference of Place Identity Perception and Landscape Preference between Residents and Tourists in Ihwa-dong Mural Village (이화동 벽화마을 주민과 관광객간의 장소 정체성 인식 및 경관 선호 차이에 관한 연구)

  • Kim, Yelim;Son, Yong-Hoon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.45 no.1
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    • pp.105-116
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    • 2017
  • Murals in villages revitalize communities and spaces, and are economically efficient. Central and local governments are therefore actively undertaking Mural Village Projects but there are some issues and concerns about the projects for the provision of uniformed landscapes for the regions that are the result of a short-term completion of projects, and instead of cohesion, cause destruction of place identities. In addition, the problem of sustainable landscape management that is the result of low community involvement can be pointed out because the murals are products of government-led projects. The study covered the context of landscape and space change processes from a critical perspective, and focused on Ihwa-dong Mural Village, which is considered the first mural village in Korea and has begun to undergo drastic changes due to attention received from media. The purposes of this study are as follows. First, the study provides data about difference of place identity perception and landscape preference between residents and tourists in Ihwa-dong Mural Village. Second, this paper evaluates the current Mural Village Projects and finds alternative directions to improve the projects by using these data. This paper analyzed tourist hot spots in Ihwa-dong Mural Village by using SNS analysis, a field study and focus group interviews. The difference of place identity perception and landscape preference was examined among three groups: residents, new residents who are invited by Mural Village Projects, and tourists. This study showed that many tourists are focused on landscape areas that were not intentionally constructed projects. In addition, the locations of preferred landscapes and stores overlapped. Meanwhile, using qualitative data analysis, it was found that residents perceived the area as being an under-privileged location, while the murals, a non-daily landscape, largely affected place identity perception of new residents and tourists. For landscape preference, tourists preferred outdoor rest areas, while new residents and residents preferred less. Additionally, new residents and tourists preferred an area's night view while residents made no mention of this. Related to the direction of the projects, three groups showed their dependence on the government. This empirical study is significant from a participatory design perspective and in analyzing the issues for mural villages' landscapes, which are spreading across the nation and proceeding without criticism in urban regeneration. Implications for urban planners and suggestions for the future projects are given.

Characteristics of Middle School Students in a Biology Special Class at Science Gifted Education Center: Self-regulated Learning Abilities, Personality Traits and Learning Preferences (과학영재교육원 생물반 중학생들의 특성: 자가조절학습능력에 따른 개인적 성향 및 학습선호도)

  • Seo, Hae-Ae
    • Journal of Gifted/Talented Education
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    • v.19 no.3
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    • pp.457-476
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    • 2009
  • The research aimed to investigate characteristics of middle school students in a biology class as science gifted education in terms of self-regulated learning abilities, personality traits and learning preferences. The twenty subject in the study responded to questionnaires of a self-regulated learning ability instrument, a personality trait tool, and a learning preference survey in March, 2009. It was found that the research subjects showed higher levels of cognitive strategies, meta-cognition, and motivation than those students in a previous study(Jung et. al., 2004), while environment was opposite. The level of cognitive strategies was significantly correlated with meta-cognition(r=.610, p=.004) and motivation (r=.538, p=.014) and meta-cognition with environment(r=.717, p=.000). Those students who showed highest levels of self-regulated learning ability displayed various personality traits. One male student with the highest level of self-regulated learning ability showed a personality of hardworking, tender-minded, and conscientious traits and wanted to be a medical doctor. The female student with the second highest level of self-regulated learning ability presented a personality as creative, abstract and divergent thinker and she showed a strong aspiration to be a world-famous biologist with breakthrough contribution. The five students with highest levels of self-regulated learning ability showed a common preference in science learning: they dislike memory-oriented and theory-centered lecture with note-taking from teacher's writings on chalkboard; they prefer science learning with inquiry-oriented laboratory work, discussion among students as well as teachers. However, reasons to prefer discussion were diverse as one student wants to listen other students' opinions while the other student want to present his opinion to other students. The most favorable science teachers appeared to be who ask questions frequently, increase student interests, behave friendly with students, and is a active person. In conclusion, science teaching for the gifted should employ individualized teaching strategies appropriate for individual personality and preferred learning styles as well as meeting with individual interests in science themes.

Removal of Arsenite by Nanocrystalline Mackinawite(FeS)-Coated Alumina (나노크기 매킨나와이트로 코팅된 알루미나에 의한 아비산염의 제거)

  • Lee, Seungyeol;Kang, Jung Chun;Park, Minji;Yang, Kyounghee;Jeong, Hoon Young
    • Journal of the Mineralogical Society of Korea
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    • v.26 no.2
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    • pp.101-110
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    • 2013
  • Due to the large specific surface area and great reactivity toward environmental contaminants, nanocrystalline mackinawite (FeS) has been widely applied for the remediation of contaminated groundwater and soil. Furthermore, nanocrystalline FeS is rather thermodynamically stable against anoxic corrosion, and its reactivity can be regenerated continuously by the activity of sulfate-reducing bacteria. However, nanocrystalline mackinawite is prone to either spread out along the groundwater flow or cause pore clogging in aquifers by particle aggregation. Accordingly, this mineral should be modified for the application of permeable reactive barriers (PRBs). In this study, coating methods were investigated by which mackinawite nanoparticles were deposited on the surface of alumina or activated alumina. The amount of FeS coating was found to significantly vary with pH, with the highest amount occurring at pH ~6.9 for both minerals. At this pH, the surfaces of mackinawite and alumina (or activated alumina) were oppositely charged, with the resultant electrostatic attraction making the coating highly effective. At this pH, the coating amounts by alumina and activated alumina were 0.038 and 0.114 $mmol{\cdot}FeS/g$, respectively. Under anoxic conditions, arsenite sorption experiments were conducted with uncoated alumina, uncoated activated alumina, and both minerals coated with FeS at the optimal pH for comparison of their reactivity. Uncoated activated alumina showed the higher arsenite removal compared to uncoated alumina. Notably, the arsenite sorption capacity of activated alumina was little changed by the coating with FeS. This might be attributed to the abundance of highly reactive hydroxyl functional groups (${\equiv}$AlOH) on the surface of activated alumina, making the arsenite sorption by the coated FeS unnoticeable. In contrast, the arsenite sorption capacity of alumina was found to increase substantially by the FeS coating. This was due to the consumption of the surface hydroxyl functional groups on the alumina surface and the subsequent occurrence of As(III) sorption by the coated FeS. Alumina, on the surface area basis, has about 8 times higher FeS coating amount and higher As(III) sorption capacity than silica. This study indicates that alumina is a better candidate than silica for the coating of nanocrystalline mackinawite.

Foundational Research on the Market Strategies and Current Status of Children's Indoor Theme Parks with Korean Characters as Their Theme (국산 캐릭터를 테마로 한 어린이 실내 테마파크의 현황 및 시장전략에 관한 기초연구)

  • Park, Seong-Sik
    • Cartoon and Animation Studies
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    • s.28
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    • pp.235-263
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    • 2012
  • Regarding the theme park business as an area of cultural content business, this study focuses on the trend of pursuing indoor theme parks as a small-scale small capital strategy escaped from the existing approach oriented to large-scale outdoor complex theme parks. It is because although existing large-scale outdoor complex theme parks require the capital with the scale of hundreds of billion won and also high-level technique and the latest operational know-how that they have a great barrier for new entry as well as enormous risk, the rent indoor theme parks succeed in market entry with efficient risk management and flexible market strategies. Thereupon, this study examines the current status of the children's indoor theme park market with Korean characters as their theme as a new market among the indoor theme parks and also investigates the market strategies of this market in the two aspects of expansion: the expansion of Korean characters' property value and the expansion of the local theme park market. For that, this article reviewed the advanced researches on theme parks and divided the types of theme parks existing in Korea with the criteria of classification by space and theme or classification by main users. Also, among the children's indoor theme parks with Korean characters as their theme, this study visited five ones located in the capital area to examine the current status. And about two located in the capital area and also four in the local area, the current data were received from the persons in charge of the companies for analysis. Also, with the subjects of spectators visiting the 'DIBO VILLAGE, Cheonggye-cheon' newly opened on April 25th, 2012, the research on satisfaction was conducted for analysis. Through that, this study analyzed the structure of the existing children's indoor theme park business with Korean characters as their theme and suggested the ground to analyze the effectiveness of market strategies being implemented. It is expected that this study will establish the clues of systematic and profound discussion for the indoor theme park business that can be said to be the niche market of the theme park business and allow the small-scale areal indoor theme parks to be examined as a significant business model for the local theme park industry. In the aspect of character business as well, it is expected that this will give a chance to establish a new model of spatial storytelling expansion in terms of the property value of Korean animation characters.

Achieving Health Equity Through Health Promotion (건강증진사업의 효율성과 형평성: 건강증진을 통한 건강 형평성 제고)

  • Moskowitz, Joel M.
    • Proceedings of The Korean Society of Health Promotion Conference
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    • 2005.09a
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    • pp.91-119
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    • 2005
  • 오타와 헌장에 따르면 건강증진은 건강형평성을 성취하는 것이다. 건강격차를 감소시키고, 모든 사람들이 건강잠재력을 달성할 수 있도록 동등한 기회와 자원이 제공되어야 한다. 또한 각 개인들은 자신의 건강에 대한 결정요인들에 대한 통제능력을 가져야 한다. 미국의 조기사망은 40%가 행동양식에 의하여, 30%가 유전적인 문제로, 15%가 사회적 환경에 의하여, 10%는 의료적 치료의 부족으로, 그리고 5%는 환경위해 물질에 대한 노출로 발생한다. 건강불평등을 발설시키는 사회적 요인으로는 경제적 요인을 들 수 있다. 이러한 요인으로 야기되는 건강불평등의 문제를 해결하여 건강형평성을 달성하기 위해서는 절대적 목표들과 평등관련 목표들이 모두 필요하다. 건강형평성은 인구집단의 건강과 함께 향상되는 것으로 나은 건강상태에 있는 사람들의 건강을 악화시키면서 건강형평성을 달성하는 것은 아니다. 각자의 관심이 형평성을 어떻게 규정하는가에 영향을 미친다. 혜택을 받은 사람들은 성과/투입의 정의를 선호하며, 소외계층은 똑같은 성과 또는 요구에 기반한 정의를 선호한다. Healthy People 2010은 미국의 국가적 예방체계를 의미하며, 가장 중요하며 예방 가능한 건강위협들을 파악하고 이러한 위협들을 감소하기 위한 목적들이 설정되어 있다. 궁극적인 목적은 건강한 삶의 질적인 면과 양적인 측면을 향상시키는 것이며, 건강불평등을 제거하는 것이다. 그러나 미국이 유럽의 국가들에 비해서 사회 프로그램에 대한 투자가 적은 이유는 재분배는 소수인종만을 위한 것이라는 믿음과, 우리는 개방되고 공정한 사회에 살고 있기 때문에 가난하다는 것은 가난한 사람들 자신들의 잘못으로 인한 것이라는 믿음 그리고 재분배를 방지하는 정치체계 때문이다. 국가기관인 CDC의 예방연구센터(Prevention Research Centers)는 지역사회 파트너들과 함께 건강증진, 질병예방, 그리고 질병과 상해로 인한 합병증을 관리하게 위한 효과적인 예방 전략을 개발하고 있다. 예방연구센터의 프로그램들은 지역사회 기반 참여연구와 소외된 계층에 중점을 두며, 다학제 간 접근방법을 활용하고, 교육기관, 공공보건기관 그리고 지역사회의 파트너들 간의 네트웍을 형성을 통한 협력관계를 강조하고 있다. 지역사회 위원회가 구성되어 있으며, 또한 근거중심 프로그램을 개발하고 있다. 이들은 건강 결정요인에 관한 연구, 형성적 연구, 개입 프로그램 및 프로그램의 확산에 관한 연구를 진행한다. UC Berkeley의 가족/지역사회 보건센터(Center for Family & Community Health)는 1993년에 설립되었다. 사업의 대상이 되는 주요 지역사회는 한국교민사회이며, 한국교민사회 자문위원회(Korean Community Advisory Board, KCAB)가 구성되어 있다. 1993년부터 2003년까지는 'Health is Strength' 사업이 시범연구사업으로 진행되었는데, 그 내용은 유방암과 자궁경부암 검진 프로그램이었다. 2003년부터 2009년까지 진행될 'Quitting is Winning'이라는 두 번째 시범연구사업은 남성들의 금연에 중점을 둔 사업이다. 'Health is Strength'는 아시아 보건서비스 및 한국교민사회 자문위원회가 함께 협력하여 진행된 사업으로, 주요 목표는 18세 이상 여성의 자궁암 조기 검진(Pap test)과 자가 유방검진 실천을 증가시키는 것이며, 50세 이상여성의 유방 임상검사와 유방 X선촬영 비율을 증가시키는 것이었다. 한 지역의 카운티에 거주하는 한국 여성들은 4년간의 개입프로그램의 대상이 되었으며, 이들을 대상으로 횡단적인 전화조사를 3번(사전, 중간, 사후)실시하였다. 개입 프로그램은 교회에서 워크샵 개최, Tell-A-Friend Form 작성하기, 포스터 및 책자 발행, 신문광고 등과 함께 자궁암 조기 검진(Pap test)과 유방 X선 촬영권을 무료로 제공하는 것으로 구성되었다. 'Quitting is Winning'은 지역사회 기반 참여 연구모형으로 한국교민사회 자문위원회는 흡연을 1순위의 사업으로 선정하였고, 근거에 기반한 금연 프로그램에 대한 연구들을 검토하여, 기존의 보편적 방법이 아닌 인터넷을 활용하는 프로그램을 진행하는 것으로 결정되었다. 이는 무작위 임상실험으로 연구대상으로 미국에 거주하는 한국인 남성흡연자 2300명을 모집하였다. 이들의 1/2은 실험군인 인터넷 프로그램 집단에, 또 다른 1/2은 대조군인 인쇄책자 집단에 무작위 할당되었다. 12개월 동안 11번의 진단이 인터넷을 통하여 진행되었으며, 참여와 참여유지에 대한 금전적인 보상이 제공되었다.

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The Settlement of Conflict in International Space Activities (우주활동에 있어서 분쟁의 해결과 예방)

  • Lee, Young-Jin
    • The Korean Journal of Air & Space Law and Policy
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    • v.25 no.1
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    • pp.159-203
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    • 2010
  • Together with the development of space science outer space law has become one of the most rapidly developing branches of international law. This reflects a general realization that these new activities must be subject to reasonable legal regulation if they are to serve the peaceful purposes of mankind without undue confusion and disorder. The exploration and use of outer space introduces many novel opportunities and dilemmas, and inspired insights are needed in the development of this new resource. In particular, the settlement of space law disputes is a relatively new discussion in international law. However, the significance of the settlement of space law disputes was acknowledged in various colloquia organized by legal academicians and practitioners around the world. Analysis of the dispute settlement provisions in space agreements plainly reveals the degree to which States persist to be mistrustful of any impingement to their sovereignty. They are reluctant to submit disputes to adjudication and binding arbitration, particularly when these provisions are negotiated between States which have dissimilar political, economic and social interests and demography. However, there is a slow but clear shift in this attitude as States realize the contemporary political, economic and technical pressures necessitating the lifting of the veil of State sovereignty. The development of an effective mechanism for the settlement of disputes arising in relation to the development of the exploration and exploitation of outer space has been the subject of global study by highly qualified publicists and international institutions. The 1972 Liability Convention is the space treaty with the most elaborate provisions for dispute settlement. However, it fails to ensure binding decisions. In this point, the 1998 Taipei Final Draft Convention may be a useful instrument for further consideration on whether an independent sectorialized dispute settlement mechanism should be established. Considering these circumstances it seemed essential to take legislative action to implement a system as comprehensive as the relevant legal framework are in the Law of the Sea and International Criminal Law mechanisms for dispute settlement and conflict avoidance from outer space activities.

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A Methodology for Extracting Shopping-Related Keywords by Analyzing Internet Navigation Patterns (인터넷 검색기록 분석을 통한 쇼핑의도 포함 키워드 자동 추출 기법)

  • Kim, Mingyu;Kim, Namgyu;Jung, Inhwan
    • Journal of Intelligence and Information Systems
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    • v.20 no.2
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    • pp.123-136
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    • 2014
  • Recently, online shopping has further developed as the use of the Internet and a variety of smart mobile devices becomes more prevalent. The increase in the scale of such shopping has led to the creation of many Internet shopping malls. Consequently, there is a tendency for increasingly fierce competition among online retailers, and as a result, many Internet shopping malls are making significant attempts to attract online users to their sites. One such attempt is keyword marketing, whereby a retail site pays a fee to expose its link to potential customers when they insert a specific keyword on an Internet portal site. The price related to each keyword is generally estimated by the keyword's frequency of appearance. However, it is widely accepted that the price of keywords cannot be based solely on their frequency because many keywords may appear frequently but have little relationship to shopping. This implies that it is unreasonable for an online shopping mall to spend a great deal on some keywords simply because people frequently use them. Therefore, from the perspective of shopping malls, a specialized process is required to extract meaningful keywords. Further, the demand for automating this extraction process is increasing because of the drive to improve online sales performance. In this study, we propose a methodology that can automatically extract only shopping-related keywords from the entire set of search keywords used on portal sites. We define a shopping-related keyword as a keyword that is used directly before shopping behaviors. In other words, only search keywords that direct the search results page to shopping-related pages are extracted from among the entire set of search keywords. A comparison is then made between the extracted keywords' rankings and the rankings of the entire set of search keywords. Two types of data are used in our study's experiment: web browsing history from July 1, 2012 to June 30, 2013, and site information. The experimental dataset was from a web site ranking site, and the biggest portal site in Korea. The original sample dataset contains 150 million transaction logs. First, portal sites are selected, and search keywords in those sites are extracted. Search keywords can be easily extracted by simple parsing. The extracted keywords are ranked according to their frequency. The experiment uses approximately 3.9 million search results from Korea's largest search portal site. As a result, a total of 344,822 search keywords were extracted. Next, by using web browsing history and site information, the shopping-related keywords were taken from the entire set of search keywords. As a result, we obtained 4,709 shopping-related keywords. For performance evaluation, we compared the hit ratios of all the search keywords with the shopping-related keywords. To achieve this, we extracted 80,298 search keywords from several Internet shopping malls and then chose the top 1,000 keywords as a set of true shopping keywords. We measured precision, recall, and F-scores of the entire amount of keywords and the shopping-related keywords. The F-Score was formulated by calculating the harmonic mean of precision and recall. The precision, recall, and F-score of shopping-related keywords derived by the proposed methodology were revealed to be higher than those of the entire number of keywords. This study proposes a scheme that is able to obtain shopping-related keywords in a relatively simple manner. We could easily extract shopping-related keywords simply by examining transactions whose next visit is a shopping mall. The resultant shopping-related keyword set is expected to be a useful asset for many shopping malls that participate in keyword marketing. Moreover, the proposed methodology can be easily applied to the construction of special area-related keywords as well as shopping-related ones.