• Title/Summary/Keyword: model stability

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Biodistribution of $^{99m}Tc$-Lactosylated Serum Albumin in Mice with Diethylnitrosamine or Thiacetamide Induced Liver Injury (Diethylnitrosamine 및 Thioacetamide 유발 간손상 생쥐에서의 $^{99m}Tc$-Lactosylated Serum Albumin의 체내 분포상)

  • Whang, Jae-Seok;Ahn, Byeong-Cheol;Sung, Young-Ok;Seo, Ji-Hyoung;Bae, Jin-Ho;Jeong, Shin-Young;Yoo, Jung-Soo;Jeong, Jae-Min;Lee, Jae-Tae;Lee, Kyu-Bo
    • The Korean Journal of Nuclear Medicine
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    • v.39 no.3
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    • pp.200-208
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    • 2005
  • Purpose: Tc-99m labeled diethylenetriaminepentaacctic acid (DTPA)-coupled galactosylated human serum albumin (GSA) is a currently used imaging agent for asialoglycoprotein receptor (ASGPR) of the liver, but, it has several shortcomings. Recently a new ASGPR imaging agent, $^{99m}Tc$-lactosylated human serum albumin (LSA), with simple labeling procedure, high labeling efficiency, high stability was developed. In order to assess the feasibility of the $^{99m}Tc$-LSA as a ASGPR imaging radiopharmaceuticals, we performed biodistribution study of the tracer in liver injured mice model and the results were compared with histolgic data. Materals and Methods: To induce hepatic damage in ICR mice, diethylnitrosamine (DEN) ($60mg/kg/week{\times}5time$, low dose or $180mg/kg/week{\times}2times$, high dose) and thioacetamide (TAA) ($50mg/kg{\times}1time$) were administrated intraperitoneally. Degree of liver damage was evaluated by tissue hematoxilin-eosin stain, and expression of asialoglycoprotein receptor (ASGPR) was assessed by immunohistochemistry using ASGPR antibody. $^{99m}Tc$-LSA was intravenously administrated via tail vein in DEN or TAA treated mice, and biodistribution study of the tracer was also performed. Results: DEN treated mice showed ballooning of hepatocyte and inflammatory cell infiltration in low dose group and severe hapatocyte necrosis in high dose group, and low dose group showed higher ASGPR staining than control mice in immunohistochemical staining. TAA treated mice showed severe hepatic necrosis. $^{99m}Tc$-LSA Biodistribution study showed that mice with hepatic necrosis induced by high dose DEN or TAA revealed higher blood activity and lower liver activity than control mice, due to slow clearance of the tracer by the liver. The degree of liver uptake was inversely correlated with the degree of histologic liver damage. But low dose DEN treated mice with mild hepatic injury showed normal blood clearance and hepatic activity, partly due to overexpression of ASGPR in mice with mild degree hepatic injury. Conclusion: Liver uptake of $^{99m}Tc$-LSA was inversely correlated with degree of histologic hepatic injury in DEN and TAA treated mice. These results support that $^{99m}Tc$-LSA can be used to evaluate the liver status in liver disease patients.

Comparison of internal and marginal fit of crown according to milling order in a single machinable wax disc (단일 절삭가공용 왁스 디스크 내에서 순차적 절삭가공 순서에 따른 크라운의 내면 및 변연 적합도 비교)

  • Song, Jun-Beom;Lee, Jonghyuk;Ha, Seung-Ryong;Choi, Yu-Sung
    • The Journal of Korean Academy of Prosthodontics
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    • v.59 no.4
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    • pp.395-404
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    • 2021
  • Purpose. The purpose of present study was to evaluate the effect of changing structural stability of wax disc on the fit of prosthesis when the milling proceeded in order. Materials and methods. Prepared maxillary left first molar was used to fabricate a Ni-Cr alloy reference model. This was scanned to design crown and then wax pattern was milled, invested and cast to fabricate prosthesis. The wax patterns located in a row centrally within a single wax disc were set into a total of five groups ranging from WM1 group that was first milled to WM5 group that was last milled and the number of each group was set as 10. Silicone replica technique was used to measure the marginal gap, axial internal gap, line angle internal gap, occlusal internal gap. Data was evaluated with one-way ANOVA with significance level set at α = .05 and then Tukey HSD test was conducted for post analysis. Results. Marginal gap measured in each group, it was 40.41 ± 2.15 ㎛ in WM1 group, 40.44 ± 2.23 ㎛ in WM2 group, 39.96 ± 2.25 ㎛ in WM3 group, 39.96 ± 2.48 ㎛ in WM4 group, and 40.57 ± 2.53 ㎛ in WM5 group. No significant difference was found between groups. The significant difference between the groups was also not found in the axial internal gap, line angle internal gap, and occlusal internal gap. Conclusion. Internal and marginal fit of single crown to the sequential order of milling processing in the single machinable wax disc did not seem to be affected by the sequence.

Factor Analysis Affecting on Changes in Handysize Freight Index and Spot Trip Charterage (핸디사이즈 운임지수 및 스팟용선료 변화에 영향을 미치는 요인 분석)

  • Lee, Choong-Ho;Kim, Tae-Woo;Park, Keun-Sik
    • Journal of Korea Port Economic Association
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    • v.37 no.2
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    • pp.73-89
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    • 2021
  • The handysize bulk carriers are capable of transporting a variety of cargo that cannot be transported by mid-large size ship, and the spot chartering market is active, and it is a market that is independent of mid-large size market, and is more risky due to market conditions and charterage variability. In this study, Granger causality test, the Impulse Response Function(IRF) and Forecast Error Variance Decomposition(FEVD) were performed using monthly time series data. As a result of Granger causality test, coal price for coke making, Japan steel plate commodity price, hot rolled steel sheet price, fleet volume and bunker price have causality to Baltic Handysize Index(BHSI) and charterage. After confirming the appropriate lag and stability of the Vector Autoregressive model(VAR), IRF and FEVD were analyzed. As a result of IRF, the three variables of coal price for coke making, hot rolled steel sheet price and bunker price were found to have significant at both upper and lower limit of the confidence interval. Among them, the impulse of hot rolled steel sheet price was found to have the most significant effect. As a result of FEVD, the explanatory power that affects BHSI and charterage is the same in the order of hot rolled steel sheet price, coal price for coke making, bunker price, Japan steel plate price, and fleet volume. It was found that it gradually increased, affecting BHSI by 30% and charterage by 26%. In order to differentiate from previous studies and to find out the effect of short term lag, analysis was performed using monthly price data of major cargoes for Handysize bulk carriers, and meaningful results were derived that can predict monthly market conditions. This study can be helpful in predicting the short term market conditions for shipping companies that operate Handysize bulk carriers and concerned parties in the handysize chartering market.

Vietnam in 2017: The Situations and Prospects of Economics, Politics, and International Relations (베트남 2017: 경제, 정치, 대외관계의 현황과 전망)

  • CHAE, Su Hong;LEE, Han Woo
    • The Southeast Asian review
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    • v.28 no.1
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    • pp.21-51
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    • 2018
  • This article takes several approaches in explaining recent developments in Vietnam. First, it draws upon an array of sources that idealize Vietnam's embrace of capitalism and integration into the global market in order to sketch out its economy's progress in 2017. Second, it observes, evaluates, and diagnoses recent changes in the Vietnamese economy in the medium to long term by incorporating conflicting perspectives on Vietnam's performance as a capitalist country. Third, this article traces the power shifts that have risen from internal struggles in the Communist Party over political and social issues. Fourth, it elaborates on the aforementioned impact that foreign relations have had on socio-political developments in Vietnam, as well as the government's response. In so doing, it also attempts to evaluate, however briefly, the significance of the 25th anniversary of South Korea-Vietnam relations. Finally, it examines the public's reaction to the post-reform transitions in light of recent sociocultural changes. 2017 was a memorable year for Vietnam: a continuous march toward capitalism; the resulting expansion of the Vietnamese people's demands; political controversies and government control; the looming instability of United States-China relations and various attempts to address the situation. These events will inevitably replicate themselves in the future as the ostensibly socialist Vietnam adopts a capitalist model. The problem is that it is unclear whether these experiences will continue with the consent of the people of socialist Vietnam or engender resistance. It is difficult to achieve meaningful consent in the status quo of worsening inequalities, widespread corruption, monopoly on power, and sustained use of unskilled low-wage workers. In other words, when concerns such as welfare, public health, and the environment are set aside in favor of economic development and commercialization as they have been, discontent, rather than consent, will prevail. It is thus important to keep a watchful eye on the viability of the nominal economic growth, surface-level political stability, and strategic responses to foreign relations that took place in 2017.

Observation of Volume Change and Subsidence at a Coal Waste Dump in Jangseong-dong, Taebaek-si, Gangwon-do by Using Digital Elevation Models and PSInSAR Technique (수치표고모델 및 PSInSAR 기법을 이용한 강원도 태백시 장성동 폐석적치장의 적치량과 침하관측)

  • Choi, Euncheol;Moon, Jihyun;Kang, Taemin;Lee, Hoonyol
    • Korean Journal of Remote Sensing
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    • v.38 no.6_1
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    • pp.1371-1383
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    • 2022
  • In this study, the amount of coal waste dump was calculated using six Digital Elevation Models (DEMs) produced between 2006 and 2018 in Jangseong-dong, Taebaek-si, Gangwon-do, and the subsidence was observed by applying the Persistent Scatterer Interferometric SAR (PSInSAR) technique on the Sentinel-1 SAR images. As a result of depositing activities using DEMs, a total of 1,668,980 m3 of coal waste was deposited over a period of about 12 years from 2006 to 2018. The observed subsidence rate from PSInSAR was -32.3 mm/yr and -40.2 mm/yr from the ascending and descending orbits, respectively. As the thickness of the waste pile increased, the rate of subsidence increased, and the more recent the completion of the deposit, the faster the subsidence tended to occur. The subsidence rates from the ascending and descending orbits were converted to vertical and horizontal east-west components, and 22 random reference points were set to compare the subsidence rate, the waste rock thickness, and the time of depositing completion. As a result, the subsidence rate of the reference point tended to increase as the thickness of the waste became thicker, similar to the PSInSAR results in relation to the waste thickness. On the other hand, there was no clear correlation between the completion time of the deposits and the rate Of subsidence at the reference points. This is because the time of completion of the deposits at all but 5 of the 22 reference points was too biased in 2010 and the correlation analysis was meaningless. As in this study, the use of DEM and PSInSAR is expected to be an effective alternative to compensate for the lack of field data in the safety management of coal waste deposits.

An Analytical Study on the Seismic Behavior and Safety of Vertical Hydrogen Storage Vessels Under the Earthquakes (지진 시 수직형 수소 저장용기의 거동 특성 분석 및 안전성에 관한 해석적 연구)

  • Sang-Moon Lee;Young-Jun Bae;Woo-Young Jung
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.27 no.6
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    • pp.152-161
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    • 2023
  • In general, large-capacity hydrogen storage vessels, typically in the form of vertical cylindrical vessels, are constructed using steel materials. These vessels are anchored to foundation slabs that are specially designed to suit the environmental conditions. This anchoring method involves pre-installed anchors on top of the concrete foundation slab. However, it's important to note that such a design can result in concentrated stresses at the anchoring points when external forces, such as seismic events, are at play. This may lead to potential structural damage due to anchor and concrete damage. For this reason, in this study, it selected an vertical hydrogen storage vessel based on site observations and created a 3D finite element model. Artificial seismic motions made following the procedures specified in ICC-ES AC 156, as well as domestic recorded earthquakes with a magnitude greater than 5.0, were applied to analyze the structural behavior and performance of the target structures. Conducting experiments on a structure built to actual scale would be ideal, but due to practical constraints, it proved challenging to execute. Therefore, it opted for an analytical approach to assess the safety of the target structure. Regarding the structural response characteristics, the acceleration induced by seismic motion was observed to amplify by approximately ten times compared to the input seismic motions. Additionally, there was a tendency for a decrease in amplification as the response acceleration was transmitted to the point where the centre of gravity is located. For the vulnerable components, specifically the sub-system (support columns and anchorages), the stress levels were found to satisfy the allowable stress criteria. However, the concrete's tensile strength exhibited only about a 5% margin of safety compared to the allowable stress. This indicates the need for mitigation strategies in addressing these concerns. Based on the research findings presented in this paper, it is anticipated that predictable load information for the design of storage vessels required for future shaking table tests will be provided.

The Development of an Aggregate Power Resource Configuration Model Based on the Renewable Energy Generation Forecasting System (재생에너지 발전량 예측제도 기반 집합전력자원 구성모델 개발)

  • Eunkyung Kang;Ha-Ryeom Jang;Seonuk Yang;Sung-Byung Yang
    • Journal of Intelligence and Information Systems
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    • v.29 no.4
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    • pp.229-256
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    • 2023
  • The increase in telecommuting and household electricity demand due to the pandemic has led to significant changes in electricity demand patterns. This has led to difficulties in identifying KEPCO's PPA (power purchase agreements) and residential solar power generation and has added to the challenges of electricity demand forecasting and grid operation for power exchanges. Unlike other energy resources, electricity is difficult to store, so it is essential to maintain a balance between energy production and consumption. A shortage or overproduction of electricity can cause significant instability in the energy system, so it is necessary to manage the supply and demand of electricity effectively. Especially in the Fourth Industrial Revolution, the importance of data has increased, and problems such as large-scale fires and power outages can have a severe impact. Therefore, in the field of electricity, it is crucial to accurately predict the amount of power generation, such as renewable energy, along with the exact demand for electricity, for proper power generation management, which helps to reduce unnecessary power production and efficiently utilize energy resources. In this study, we reviewed the renewable energy generation forecasting system, its objectives, and practical applications to construct optimal aggregated power resources using data from 169 power plants provided by the Ministry of Trade, Industry, and Energy, developed an aggregation algorithm considering the settlement of the forecasting system, and applied it to the analytical logic to synthesize and interpret the results. This study developed an optimal aggregation algorithm and derived an aggregation configuration (Result_Number 546) that reached 80.66% of the maximum settlement amount and identified plants that increase the settlement amount (B1783, B1729, N6002, S5044, B1782, N6006) and plants that decrease the settlement amount (S5034, S5023, S5031) when aggregating plants. This study is significant as the first study to develop an optimal aggregation algorithm using aggregated power resources as a research unit, and we expect that the results of this study can be used to improve the stability of the power system and efficiently utilize energy resources.

The Association between Patient Characteristics of Chungnam-do and External Medical Service Use Using Health Insurance Cohort DB 2.0 (건강보험 코호트 자료를 활용한 충청남도 지역 환자의 특성에 따른 관외 의료이용과의 연관성)

  • Yeong Jun Lee;Se Hyeon Myeong;Hyun Woo Moon;Seo Hyun Woo;Sun Jung Kim
    • Health Policy and Management
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    • v.34 no.1
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    • pp.48-58
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    • 2024
  • Background: The purpose of this study was to investigate the association between external medical service use and the characteristics of Chungcheongnam-do patients. We aimed to provide evidence of external medical service use enhance the healthcare delivery system in Chungcheongnam-do. Methods: We used the Health Insurance Cohort DB 2.0 of 2016-2019, and 2,570,439 patients were included in the study. Multivariate logistic regression and multinomial logistic regression were used to identify the association between external medical service use and each patient characteristic. Generalized linear model was used to identify the association between medical costs and external medical service use area. Results: During the study period, 32.2% of inpatients and 12.5% of outpatients had external medical service use in Chungcheongnam-do. In comparison to patients living in Cheonan and Asan, the odds ratio (OR) for external medical services use was higher across all regions. Specifically, hospitalized patients from Gyeryong, Nonsan, and Geumsan (OR, 116.817) and Gongju, Buyeo, and Cheongyang (OR, 72.931) demonstrated extremely high likelihood of external medical service use in the Daejeon area. Furthermore, compared to medical expenses incurred within Chungcheongnam-do, patients with external medical service use in the capitol area (outpatient=17.01%, inpatients=22.11%) and Daejeon area (outpatient=16.63%, inpatients=15.41%) spent more on healthcare services. Conclusion: This study found the evidence of external medical service use among Chungcheongnam-do patients. Further study should be conducted taking into account variables including satisfaction of local medical services, different types of patient diseases, and others. The study's findings may serve as a foundation for policy proposals aimed at ensuring the financial stability of our health insurance system, ensuring the efficient delivery of medical care, and localization of medical care.

Qualitative Study about Value Cognition and Benefits of Consumer on Culture-Art products (문화예술상품에 대한 소비자의 가치인식과 추구혜택에 관한 질적 연구)

  • Rhee, Young-Sun;Shin, Eun-Joo
    • Asia Marketing Journal
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    • v.12 no.4
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    • pp.27-54
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    • 2011
  • This research attempted to present the efficiency of culture marketing to the organizations producing culture-art products and to the companies utilizing art and suggest the practical viewpoints to the culture and art policy agencies. The methodology used was to take an in-depth look at the consumer value cognition and benefits of culture-art products in contemporary consumption culture from a social context by conducting a total of 12 Focus Group Interviews, consisting of 58 males and females in their 10s~50s who can represent culture-art product consumers. The culture-art products refer to the artist's spiritual, actual act of creating or to the end products with economic exchange value. They are also sense goods and merit goods that affect the mental state of consumers. By looking at culture-art products as consumer merit goods, this research examined consumer value cognition of culture-art products based on the characteristics culture-art products. As a result, this research determined that consumers view culture-art products largely as 'aesthetic and sensuous merit goods', 'actual and individual merit goods', and 'social public property'. As 'aesthetic and sensuous merit goods', culture-art products are considered as the products of an artist's creative activities; as 'social public property', culture-art products have a public value in terms of ownership; and as 'actual and individual merit goods', culture-art products act on the spirit and reality of a consumer in terms of consumption. As a result of analyzing the benefits of culture-art products based on the above-mentioned consumer value cognition, it was observed that the benefits of culture-art-product consumption are chiefly divided into 'aesthetic character-oriented', 'social relationships-oriented', and 'individual benefits-oriented' depending on how consumers see culture-art products. A 3-conceptional structures model was constructed according to the relationship between consumer value cognition of culture-art products and the benefits. This research revealed that consumers who pursue the aesthetic value or sense of beauty as the central reason experience culture-art products themselves, enjoy intellectual quests, and pursue their satisfaction by expressing affection for and interests in culture-art products. On the other hand, consumers who pursue social value as the central reason as a means of communication by perceiving culture-art products as a public property of society, pursue sympathy with people close to them through the symbolic power of culture-art product consumption or the joy of self-display. Consumers who perceive art products as spiritual and actual merit goods and pursue consumer value as a central reason want to express their own personality, develop themselves, and differentiate themselves or identify themselves with others in the context of social relations for the ultimate goal of living a happy and satisfied life while pursuing to satisfy imminent and actual necessities as emotional stability and rest. The fact that culture-art product benefits could vary according to how a consumer perceives them implies that consumer value cognition of culture-art products and their benefits significant affect consumers' decision in choosing and consuming various culture-art products. It turned out that such benefits from the consumption of culture-art products reflect the complex contemporary consumption culture of rational consumption, symbolic consumption, experiential consumption, and social reflective consumption. This research identified conceptional structures of consumer value cognition on culture-art products and benefits that can be used for studying and understanding culture-art products consumers who pursue a variety of consumption values. They can also be used by private companies in utilizing art, as well as by national agencies in enhancing the population's quality of life. However, since this research could only conceptually grasp consumer perception of culture-art products and reveal the dimension of classification due to its own limitations arising from characteristic investigation, quantitative data on the benefits of culture-art product consumers should be measured in future studies through a quantitative investigation, while using the value cognition of culture-art products and the individual characteristics of consumers as variables based on this research.

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Developing a Scale for Measuring the Corporate Social Responsibility Activities of Korea Corporation: Focusing on the Consumers' Awareness (한국형 기업의 사회적 책임활동 측정을 위한 척도 개발 연구: 소비자 인식을 중심으로)

  • Park, Jongchul;Kim, Kyungjin;Lee, Hanjoon
    • Asia Marketing Journal
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    • v.12 no.2
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    • pp.27-52
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    • 2010
  • It is not new that today's business organizations are expected to exhibit ethical and moral management and to carry out social responsibility as a good corporate citizen. Since South Korea emerged as a newly industrialized country during the 1980s, Korean corporations have become active in carrying out their social responsibility as a good corporate citizen to society. In spite of the short history of corporate social responsibility, Korean companies have actively participated in corporate philanthropy. Corporations' significant donations to various social causes, no-lay-off policies, corporate volunteerism and green marketing are evidences of their commitment to corporate citizenship. Corporate social responsibility is now an essential management practice whereby corporation can strengthen its sustainable value creation processes by enhancing the trust assets underlying the relationships between the business and the stakeholders. Much of the conceptual work in the area of corporate social responsibility(CSR) has originated from researches conducted in the management field. Carroll(1979) proposed that corporations have four types of social responsibilities: economic, legal, ethical and philanthropic responsibility. Most past research has investigated CSR and its impact on consumers' attitudes toward the corporations and corporate performances. Although there exists a large body of literature on how consumers perceive and respond to CSR, the majority of past studies were conducted in the United States. The stability and applicability of past findings need to be tested across different national/cultural settings, especially since corporate social responsibility is a reflection of implicit conformation with the expectations and criticism that society may have toward a corporation(Matten and Moon, 2004). In this study, we explored whether people in Korea perceive CSR of Korean corporations in the same four dimensions as done in the United States and what were the measurement items tapping each of these four dimensions. In order to investigate the dimensions of CSR and the measurement items for CSR perceived by Korean people, nine focus group interviews were conducted with several stakeholder groups(two with undergraduate students, two with graduate students, three with general consumers, and two with NGO groups). Scripts from the interviews revealed that the Korean stakeholders perceived four types of CSR which are the same as those proposed by Carroll(1979). However we found CSR issues unique to Korean corporations. For example for the economic responsibility, Korean people mentioned that the corporation needed to contribute to the economic development of the country by generating corporate profits. For the legal responsibility, Koreans included the "corporation need to follow the consumer protection law." For the ethical responsibility, they considered that the corporation needed to not promote false advertisement. In addition, Koreans thought that an ethical company should do transparent management. For the philanthropic responsibility, people in Korea thought that a corporation needed to return parts of its profits to the society for the betterment of society. The 28 items were developed based on the results of the nine focus group interviews, while considering the scale developed by Maignan and Ferrell(2001). Following the procedure proposed by Churchill(1979), we started by developing an item poll consisting of 28 items and purified the initial pool of items through exploratory, confirmatory factor analyses. 176 samples were sued for this analysis. Confirmatory factor analysis was performed on the 28 items in order to verify the underlying four factor structure. Study 1 provided new measurement items for tapping the Korean CSR dimensions, which can be useful for the future studies exploring the effects of CSR on Korean consumers' attitudes toward the corporations and corporate performances. And we found the CSR scale(17 items) has good reliability, discriminant validity and nomological validity. Economic Responsibility: "XYZ company continuously improves the quality of our products", "XYZ company has a procedure in place to respond to customer complaint", "XYZ company contributes to the economic development of our country by generating profits", "XYZ company is eager to hire people". Legal Responsibility: "XYZ company's products meet legal standards", "XYZ company seeks to comply with all laws regulating hiring and employee benefits", "XYZ company honors contractual obligations to its suppliers", "XYZ company's managers try to comply with the law related to the business operation". Ethical Responsibility: "XYZ company has a comprehensive code of conduct", "XYZ company does not promote a false or misleading advertisement", "XYZ company seems to conduct a transparent business", "XYZ company does a fair business with its suppliers or sub-contractors". Philanthropic Responsibility: "XYZ company encourages partnerships with local businesses and schools", "XYZ company supports sports and cultural activities", "XYZ company gives adequate contributions to charities considering its business size", "XYZ company encourages employees to support our community". Study 2 was condusted for comprehensive validity. 655 samples were used for this anlysis. Collected samples were tested by factor analysis and Crnbach's Alpha coefficiednts and were found to be satisfactory in terms of validity and reliability. Furthermore, fitness of the measurement model was tested by using conformatory factor analysis. χ2=880.73(df=160), GFI=0.891, AGFI=0.854, NFI=0.908, NNFI=0.913, RMR=0.059, RMESA=0.070. We hope that CSR scale could greatly facilitate research on Corporate social resposibility, it is by no means the final answer.

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