• 제목/요약/키워드: 2D-modeling

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Development of a smart cane concept for guiding the visually impaired - focused on design thinking learning practices for students - (시각장애인을 위한 길 안내용 스마트 지팡이 콘셉트 개발)

  • Park, Hae Rim;Lee, Min Sun;Yang, Ho Jung
    • Journal of Service Research and Studies
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    • 제13권1호
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    • pp.186-200
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    • 2023
  • This study aims to improve the usability of the white cane, which is walking equipment that most local visually impaired people use and carry when going out, and to contribute to the prevention of safety accidents and the walking rights of visually impaired people by providing improvement and resolution measures for the problems identified. Also, this study is a study on the visually impaired, primarily targeting the 1st to 2nd degree visually impaired people, who cannot go out on their own without walking equipment such as a white cane, corresponding to 20% among approximately 250,000 blind and low vision people in the Korean population. In the study process, the concept has been developed from the user's point of view in order that the white cane becomes a real help in the walking step of the visually impaired and the improvement of usability of the white cane, the main walking equipment for the visually impaired, are done by problem identification through the Double Diamond Model of Design Thinking (Empathize → Define → Ideate → Prototype → Test (verify)). As a result of the investigation in the process of Empathy, a total of five issues was synthesized, including an increase in the proportion of the visually impaired people, an insufficient workforce situation to help all the visually impaired, an improvement and advancement of assistive devices essential for the visually impaired, problems of damage, illegal occupation, demolition, maintenance about braille blocks, making braille block paradigms for the visually impaired and for everyone. In Ideate and Prototype steps, situations derived from brainstorming were grouped and the relationship were made through the KJ method, and specific situations and major causes were organized to establish the direction of the concept. The derived solutions and major functions are defined in four categories, and representative situations requiring solutions and major functions are organized into two user scenarios. Ideas were visualized by arranging the virtual Persona and Customer Journey Map according to the situation and producing a prototype through 3D modeling. Finally, in the evaluation, the final concept derived is a device such a smart cane for guidance for the visually impaired as ① a smart cane emphasizing portability + ② compatibility with other electronic devices + ③ a product with safety and convenience.

Methods for Genetic Parameter Estimations of Carcass Weight, Longissimus Muscle Area and Marbling Score in Korean Cattle (한우의 도체중, 배장근단면적 및 근내지방도의 유전모수 추정방법)

  • Lee, D.H.
    • Journal of Animal Science and Technology
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    • 제46권4호
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    • pp.509-516
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    • 2004
  • This study is to investigate the amount of biased estimates for heritability and genetic correlation according to data structure on marbling scores in Korean cattle. Breeding population with 5 generations were simulated by way of selection for carcass weight, Longissimus muscle area and latent values of marbling scores and random mating. Latent variables of marbling scores were categorized into five by the thresholds of 0, I, 2, and 3 SD(DSI) or seven by the thresholds of -2, -1, 0,1I, 2, and 3 SD(DS2). Variance components and genetic pararneters(Heritabilities and Genetic correlations) were estimated by restricted maximum likelihood on multivariate linear mixed animal models and by Gibbs sampling algorithms on multivariate threshold mixed animal models in DS1 and DS2. Simulation was performed for 10 replicates and averages and empirical standard deviation were calculated. Using REML, heritabilitis of marbling score were under-estimated as 0.315 and 0.462 on DS1 and DS2, respectively, with comparison of the pararneter(0.500). Otherwise, using Gibbs sampling in the multivariate threshold animal models, these estimates did not significantly differ to the parameter. Residual correlations of marbling score to other traits were reduced with comparing the parameters when using REML algorithm with assuming linear and normal distribution. This would be due to loss of information and therefore, reduced variation on marbling score. As concluding, genetic variation of marbling would be well defined if liability concepts were adopted on marbling score and implemented threshold mixed model on genetic parameter estimation in Korean cattle.

Implementation of Radiotherapy Educational Contents Using Virtual Reality (가상현실 기술을 활용한 방사선치료 교육 콘텐츠 제작 구현)

  • Kwon, Soon-Mu;Shim, Jae-Goo;Chon, Kwon-Su
    • Journal of the Korean Society of Radiology
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    • 제12권3호
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    • pp.409-415
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    • 2018
  • The development of smart devices has brought about significant changes in daily life and one of the most significant changes is the virtual reality zone. Virtual reality is a technology that creates the illusion that a 3D high-resolution image has already been created using a display device just like it does in itself. Unrealized subjects are forced to rely on audiovisual materials, resulting in a decline in the concentration of practices and the quality of classes. It used virtual reality to develop effective teaching materials for radiology students. In order to produce a video clip bridge using virtual reality, a radiology clinic was selected to conduct two exposures from July to September 2017. The video was produced taking into account the radiology and work flow chart and filming was carried out in two separate locations : in the computerized tomography unit and in the LINAC room. Prior to filming the scenario and the filming route were checked in advance to facilitate editing of the video. Modeling and mapping was performed in a PC environment using the Window XP operating system. Using two leading virtual reality camera Gopro Hero, CC pixels were produced using a 4K UHD, Adobe, followed by an 8 megapixel resolution of $3,840{\times}2,160/4,096{\times}2,160$. Total regeneration time was performed in about 5 minutes during the production of using virtual reality to prevent vomiting and dizziness. Currently developed virtual reality radiation and educational contents are being used to secure the market and extend the promotion process to be used by various institutions. The researchers will investigate the satisfaction level of radiation and educational contents using virtual reality and carry out supplementary tasks depending on the results.

A Study on Geophysical Characteristics and Regional Geological Structures of the Southwestern Yellow Sea of Korea using Gravity and Magnetic Data (중력 및 자력자료를 이용한 황해 남서부해역의 지구물리학적 특성 및 광역 지구조 연구)

  • Kim, Chang-Hwan;Park, Chan-Hong
    • Journal of the Korean earth science society
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    • 제31권3호
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    • pp.214-224
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    • 2010
  • Gravity and Magnetic survey data were analyzed to investigate the geophysical characteristics and regional geological structures of the southwestern Yellow Sea. The set of data about the southwestern part of the Yellow Sea in Korea was one collected by the Korea Ocean Research and Development Institute (KORDI) in 2003, 2004, and 2005. The Yellow Sea has a few basins and the study area also includes parts of the Heuksan Basin and the East China Sea Basin. The bathymetry of the study area ranges from about ?40 m southwestward near China to about 150 m northeastward near Korea. The bathymetry has the gentle rise and fall and the smooth slope. The gravity anomalies, from sea surface gravity and satellite gravity data, reflect the basement rocks rather than the smooth bathymetry. The gravity anomalies are higher on Northeastern part of the study area and lower over the South of the Heuksan Basin. The analytic signal from the Bouguer anomaly shows higher anomalous zones near the boundaries of the basins. The magnetic anomalies and the analytic signal, from the magnetic data, suggest that the complex anomalies on the Northern part are attributed to the volcanic intrusions and that the smooth patterns in the Southern part are based on the lack of the intrusions. The power spectrum analysis of the Bouguer anomalies and the magnetic anomalies indicate that the depth to the Moho discontinuity varies from about 30.2 to 28.3 km and that the depths of the basement rocks and the Eocene discontinuity range from about 8.4 to 8 km and from about 1.5 to 1.7 km, respectively. The inversion of the Bouguer anomaly shows that the Moho depth to the Western part of the study area near China is slightly deeper than the Eastern part near Korea. The result of 2-D gravity modeling has a good coherence with the results of the analytic signal, the power spectrum analysis, and the inversion.

THE THREE DIMENSIONAL FINITE ELEMENT ANALYSIS OF STRESS DISTRIBUTION AND DEFORMATION IN MANDIBLE ACCORDING TO THE POSITION OF PONTIC IN TWO IMPLANTS SUPPORTED THREE-UNIT FIXED PARTIAL DENTURE (두 개의 임플란트를 이용한 3본 고정성 국소의치에서 가공치 위치에 따른 하악골에서의 응력 분포 및 변형에 관한 삼차원 유한요소법적 연구)

  • Kim, Dong-Su;Kim, Il-Kyu;Jang, Keum-Soo;Park, Tae-Hwan;Kim, Kyu-Nam;Son, Choong-Yul
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제34권2호
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    • pp.166-179
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    • 2008
  • Excessive concentration of stress which is occurred in occlusion around the implant in case of the implant supported fixed partial denture has been known to be the main cause of the crestal bone destruction. Therefore, it is essential to evaluate the stress analysis on supporting tissue to get higher success rates of implant. The purpose of this study was to evaluate the effects of stress distribution and deformation in 3 different types of three-unit fixed partial denture sup-ported by two implants, using a three dimensional finite element analysis in a three dimensional model of a whole mandible. A mechanical model of an edentulous mandible was generated from 3D scan, assuming two implants were placed in the left premolars area. According to the position of pontic, the experiments groups were divided into three types. Type I had a pontic in the middle position between two implants, type II in the anterior posi-tion, and type III in the posterior position. A 100-N axial load was applied to sites such as the central fossa of anterior and posterior implant abutment, central fossa of pontic, the connector of pontic or the connector between two implants, the mandibular boundary conditions were modeled considering the real geometry of its four-masticatory muscular supporting system. The results obtained from this study were as follows; 1. The mandible deformed in a way that the condyles converged medially in all types under muscular actions. In comparison with types, the deformations in the type II and type III were greater by 2-2.5 times than in the type I regardless of the loading location. 2. The values of von Mises stresses in cortical and cancellous bone were relatively stable in all types, but slightly increased as the loading position was changed more posteriorly. 3. In comparison with type I, the values of von Mises stress in the implant increased by 73% in Type II and by 77% in Type III when the load was applied anterior and posterior respectively, but when the load was applied to the middle, the values were similar in all types. 4. When the load was applied to the centric fossa of pontic, the values of von Mises stress were nearly $30{\sim}35%$ higher in the type III than type I or II in the cortical and cancellous bone. Also, in the implant, the values of von Mises stress of the type II or III were $160{\sim}170%$ higher than in the type I. 5. When the load was applied to the centric fossa of implant abutment, the values of von Mises stress in the cortical and cancellous bone were relatively $20{\sim}25%$ higher in the type III than in the other types, but in the implant they were 40-45% higher in the type I or II than in the type III. According to the results of this study, musculature modeling is important to the finite element analysis for stress distribution and deformation as the muscular action causes stress concentration. And the type I model is the most stable from a view of biomechanics. Type II is also a clinically accept-able design when the implant is stiff sufficiently and mandibular deformation is considered. Considering the high values of von Mises stress in the cortical bone, type III is not thought as an useful design.

Dose Distribution and Characterization for Radiation Fields of Multileaf Collimateor System (방사선 입체조형치료용 다엽콜리메이터의 특성과 조직내 선량분포 측정)

  • Chu, Sung-Sil;Kim, Gwi-Eon
    • Radiation Oncology Journal
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    • 제14권1호
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    • pp.77-85
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    • 1996
  • Purpose : Multileaf collimator(MLC) is very suitable tool for conformal radio-therapy and commissioning measurements for a multileaf collimator installed on a dual energy accelerator with 6 and 10MV photons are required, For modeling the collimator with treament planning software, detailed dosimetric characterization of the multileaf collimator including the penumbra width, leaf transmission between leaf leakage and localization of the leaf ends and sides is an essential requirement. materials and Methods : Measurement of characteristic data of the MLC with 26 pair block leaves installed on CLINAC 2100C linear accelerator was performed. Low sensitive radiographic film(X-omatV) was used for the penumbra measurement and separate experiments using radiographic film and thermoluminescent dosimeters were performed to verify the dose distribution, Measured films were analized with a photodensitometer of WP700i scanner. Results : For 6 & 10 MV x-ray energies, approximately $2.0\%$ of photons incident on the multileaf collimator were transmitted and an additional $0.5\%$ leakage occurs between the leaves. Localizing the physical end of the leaves showed less than 1mm deviation from the $50\%$ decrement line and this difference is attributed to the curved shaped end on the leaves One side of a sin히e leaf corresponded to the $50\%$ decrement line, but the opposite face was aligned with a lower value. This difference is due to the tongue and groove used to decrease between leaf leakage. Alignment of the leaves to form a straight edge resulted larger penumbra at far position from isocenter as compare with divergent alloy blocks. When the MLC edge is stepped by sloping field, the isodose lines follow the leaf pattern and Produce scalloping isodose curves in tissue. The effective penumbra by 45 degree stepped MLC is about 10mm at 10cm depth for 6MV x-ray. The difference of effective penumbra in deep tissue between MLC and divergent alloy blocks is small (5mm). Conclusion : Using the characteristic data of MLC, the MLC has the clinlical acceptability and suitability for 3-D conformal radiotherapy except small field size.

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Predicting Forest Gross Primary Production Using Machine Learning Algorithms (머신러닝 기법의 산림 총일차생산성 예측 모델 비교)

  • Lee, Bora;Jang, Keunchang;Kim, Eunsook;Kang, Minseok;Chun, Jung-Hwa;Lim, Jong-Hwan
    • Korean Journal of Agricultural and Forest Meteorology
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    • 제21권1호
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    • pp.29-41
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    • 2019
  • Terrestrial Gross Primary Production (GPP) is the largest global carbon flux, and forest ecosystems are important because of the ability to store much more significant amounts of carbon than other terrestrial ecosystems. There have been several attempts to estimate GPP using mechanism-based models. However, mechanism-based models including biological, chemical, and physical processes are limited due to a lack of flexibility in predicting non-stationary ecological processes, which are caused by a local and global change. Instead mechanism-free methods are strongly recommended to estimate nonlinear dynamics that occur in nature like GPP. Therefore, we used the mechanism-free machine learning techniques to estimate the daily GPP. In this study, support vector machine (SVM), random forest (RF) and artificial neural network (ANN) were used and compared with the traditional multiple linear regression model (LM). MODIS products and meteorological parameters from eddy covariance data were employed to train the machine learning and LM models from 2006 to 2013. GPP prediction models were compared with daily GPP from eddy covariance measurement in a deciduous forest in South Korea in 2014 and 2015. Statistical analysis including correlation coefficient (R), root mean square error (RMSE) and mean squared error (MSE) were used to evaluate the performance of models. In general, the models from machine-learning algorithms (R = 0.85 - 0.93, MSE = 1.00 - 2.05, p < 0.001) showed better performance than linear regression model (R = 0.82 - 0.92, MSE = 1.24 - 2.45, p < 0.001). These results provide insight into high predictability and the possibility of expansion through the use of the mechanism-free machine-learning models and remote sensing for predicting non-stationary ecological processes such as seasonal GPP.

The Determination of Trust in Franchisor-Franchisee Relationships in China (중국 프랜차이즈 시스템에서의 본부와 가맹점간 신뢰의 영향요인)

  • Shin, Geon-Cheol;Ma, Yaokun
    • Journal of Global Scholars of Marketing Science
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    • 제18권2호
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    • pp.65-88
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    • 2008
  • Since the implementation of economic reforms in 1978, the Chinese economy grows rapidly at an average annul growth rate of 9% over the post two decades. Franchising has been widely recognized as an important source of entrepreneurial activity. Trust is important in that it facilitates relational exchanges by permits partners to transcend short-run inequities or risks to concentrate on long-term profits or gains. In the relationship between the franchisors and franchisees, trust has been described as an important source of competitive advantage. However, little research has been done on the factors affecting trust in Chinese franchisor-franchisee relationships. The purpose of this study is to investigate what factors affect the trust in the franchise system in China, and to provide guidelines and insights to franchisors which enter Chinese market. In this study, according to Morgan and Hunt (1994), trust is defined as the extending when one party has confidence in an exchange partner's reliability and integrity. We offered a conceptual model of the empirical study. The model shows that the factors affecting the trust include franchisor's supports, communication, satisfaction with previous outcome and conflict. We also suggested the franchisor's supports and communication like to enhance the franchisee's satisfaction with previous outcome, and the franchisor's supports, communication and he franchisee's satisfaction with previous outcome tend to decrease conflict. Before the formal study, a pretest involving exploratory interviews with owners from three franchisees was conducted to make sure the questionnaire was relevant and clear to the respondents. The data were collected using trained interviewers to carry out personal interviews with the aid of an unidentified, muti-page, structured questionnaire. The respondents comprised of owners, managers, and owner managers of franchisee-owned food service franchises located in Beijing, China. Even though a total of 256 potential franchises were initially contacted, the finally usable sample consisted of 125 respondents. As expected, the sampling method was successful in soliciting respondents with waried personal and firm characteristics. Self-administrated questionnaires were used for all measures. And established scales were used to measure the latent constructs in this study. The measures tapped the franchisees' perceptions of the relationship with the referent franchisor. Five-point Likert-type scales ranging from "strongly disagree" (=1) to "strongly agree" (=7) were used throughout the constructs (trust, eight items; support, five items; communication, four items; satisfaction, six items; conflict, three items). The reliability measurements traditionally employed, such as the Cronbach's alpha, were used. All the reliabilities were greater than.80. The proposed measurement model was estimated using SPSS 12.0 and AMOS 5.0 analysis package. We conducted A series of exploratory factor analyses and confirmatory factor analyses to assess the convergent validity, discriminant validity, and reliability. The results indicate reasonable overall fits between the model and the observed data. The overall fit of measurement model were $X^2$= 159.699, p=0.004, d.f. = 116, GFI =.879, NFI =.898, CFI =.969, IFI =.970, TLI =.959, RMR =.058. The results demonstrated that the data reasonably fitted the model. We also examined construct reliability and reliability and average variance extracted (AVE). The construct reliability of each construct was greater than.80 and the AVE of each construct was greater than.50. According to the analysis of Structure Equation Modeling (SEM), the results of path model indicated an adequate fit of the model: $X^2$= 142.126, p = 0.044, d.f. = 115, GFI =.892, NFI =.909, CFI =.981, IFI =.981, TLI =.974, RMR =.057. As hypothesized, the results showed that it is strategically important to establish trust in a franchise system, and the franchisor's supports, communication and satisfaction with previous outcome tend to reinforce franchisee's trust. The results also showed trust seems to decrease as the experience of conflict episodes increases. And we also noticed that franchisor's supports and communication tend to enhance the franchisee's satisfaction with previous outcome, and communication tend to decrease conflict. If the trust between the franchisor and franchisee can be established in a franchise system, franchising offers many benefits and reduces many costs. To manage a mutual trust of relationship with their franchisees, franchisor's should provide support effectively to their franchisees. Effective assistant services have direct effect on franchisees' satisfaction with previous outcome and trust in franchisor. Especially, franchise sales process, orientation, and training in the start-up period are key elements for success of the franchise system. Franchisor's support is an accumulated separate satisfaction evaluation with different kind of service provided by the franchisor. And providing support definitely can improve the trustworthy image of the franchisor. In the franchise system, conflicts of interests and exertions of different power sources are very common. The experience of conflict episodes seems to negatively relate to trust. Therefore, it is important to reduce the negative side of the relationship conflicts. Communication actually plays a broader role in reducing conflict and establish mutual trust in franchisor-franchisee relationship. And effective communication between franchisors and franchisees can improve franchisees' satisfaction toward the franchise system. As the diversification of Chinese markets, both franchisors and franchisees must keep the relevant, timely, and reliable communication. And it is very important to improve the quality of communication. Satisfaction with precious outcomes seems to positively relate to trust. Franchisors and franchisees that are highly satisfied with the previous outcomes that flow from their relationship will perceive their partner as advancing their goal achievement. Therefore, it is necessary for both franchisor and their franchisees to make the welfare of partner with effort. Little literature has focused on what factors affect the trust between franchisors and their franchisees in China. This study developed the hypotheses regarding the factors affecting trust in the transaction relationship. The results of data analysis supported the hypotheses strongly. There are certain limitations in this study. First, we may point out that some other factors missed in this study could be significantly important. Second, the context of this study, food service industry, limits its potential generalizability for all franchise systems. More studies in different categories of franchise system are needed to broaden its generalizability. Third, the model was tested empirically in a sample in Beijing, more empirical tests of the proposed model in other Chinese areas are needed. Finally, the analysis in this study was solely based on the perception of franchisees and the opinions of franchisors were not included.

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The Relationship between Trust, Trustworthiness, and Repeat Purchase Intentions: A Multidimensional Approach (신뢰대상의 다차원적 접근법에 의한 신뢰와 재구매 의도와의 관계)

  • Lee, Soo-Hyung;Park, Mi-Ryong
    • Journal of Global Scholars of Marketing Science
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    • 제18권1호
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    • pp.1-31
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    • 2008
  • Trust is central to human relationships, at all times and places. The importance of trust is fundamental in all areas of human life, not only in the area of business administration. 2,500 years ago in China, Confucius taught that the foundation of politics was the trust of the people, more important even than military strength or the supply of food. Shakespeare's play, "Much Ado about Nothing' is about trust and deception. These days, trust and transparency in a commercial organization's business culture form the basis of the 'social capital' by which that organization increases its productivity. A successful company raises productivity by the accumulation of social capital, derived from a trust relationship between business partners, and between the company and consumers. Trust is the crucial factor. At the national level, building trust determines a nation's competitiveness. For a company, long term trust relationships with customers are essential for its survival in a business environment of rapid change. Such relationships, based on trust, are important assets to ensure a company's competitive advantage, and need to be organic to that company's business culture. Because of this importance, trust relationships have been studied in diverse areas within business administration, and especially within marketing, where they form the basis of a successful relationship between producer and consumer. However, what has been lacking is a unified definition of trust. Research has been conducted on the basis of various definitions and models. The majority of researchers have not considered the multidimensional character of the concept of trust until now. Approaches based on a one dimensional model have undermined the value of research results. Furthermore, researchers have only considered trust and trustworthiness as a single component. The majority of research has explored the consequences of perceived trust for outcomes such as loyalty or cooperation, but has neglected the effects of trustworthiness upon the mechanisms of consumer trust. This study focuses on the dimension of trust from such a perspective. It seeks to verify the effect of trust on customer intentions by breaking it down into three separate components: 1) the salesperson, 2) the product/service, and 3) the company. The purposes of this paper are as follows: Firstly, we review the multidimensional nature of trust objects: the salesperson, the product/service, and the company. Secondly, we analyze the relationship between multidimensional trust and trustworthiness. Thirdly, we analyze the connection between trust and repeat purchase intentions for the maintenance of long term relationships. For these purposes the author has developed several hypotheses as follows: H1-1: The competence of a salesperson is positively associated with the trust given by the consumer to the salesperson. H1-2: The benevolence of a salesperson is positively associated with the trust given by the consumer to the salesperson. H2-1: The competence of product/service is positively associated with the trust given by the consumer to the product/service. H2-2: The benevolence of product/service is positively associated with the trust given by the consumer to the product/service. H3-1: The reputation of a company is positively associated with the trust given by the consumer to the company. H3-2: The physical environment of a company is positively associated with the trust given by the consumer to the company. H4-1: Trust in a salesperson is positively associated with repeat purchase intentions. H4-2: Trust in a product/service is positively associated with repeat purchase intentions. H4-3: Trust in a company is positively associated with repeat purchase intentions. The data was compiled from 366 questionnaires. 500 questionnaires were collected, but some of the data was considered unsuitable and inappropriate. The subjects of the survey were male and female customers purchasing products at department stores in Seoul, Daegu and Gyeongbuk. It was carried out between Oct. 25 and 29, 2007. The data was analyzed by frequency analysis using SPSS 12.0 and structural equation modeling using LISREL 8.7. The result of the overall model analysis is as follows: Chi-Square=445.497, d.f.=185, p-value=0.0, GFI=.901, RMSEA=.0617, NNFI=.986, NFI=.981, CFI=.989, AGFI=.864, RMR=.0872. The results of the overall model analysis were coherent. It was found that trust is a multi-dimensional construct, that each of the dimensions of trust are meaningful influences on customer's repurchase intention. Trust in a company may be the most relevant, while trust in a product/service and a salesperson may be less relevant to repurchase intentions. The effective factors in determining trust in a salesperson and a company's product/service were found to be competence and benevolence. Factors in determining trust in a company were its reputation and physical environment, and the relationship of each effective trust factor has been verified in this research. As a result, it was found that competence and benevolence have a meaningful influence on trust in a salesperson and in product/service. It was also found that a company's reputation influences the overall trust in the company significantly but a company's physical environment does not have much effect.

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DISEASE DIAGNOSED AND DESCRIBED BY NIRS

  • Tsenkova, Roumiana N.
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1031-1031
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    • 2001
  • The mammary gland is made up of remarkably sensitive tissue, which has the capability of producing a large volume of secretion, milk, under normal or healthy conditions. When bacteria enter the gland and establish an infection (mastitis), inflammation is initiated accompanied by an influx of white cells from the blood stream, by altered secretory function, and changes in the volume and composition of secretion. Cell numbers in milk are closely associated with inflammation and udder health. These somatic cell counts (SCC) are accepted as the international standard measurement of milk quality in dairy and for mastitis diagnosis. NIR Spectra of unhomogenized composite milk samples from 14 cows (healthy and mastitic), 7days after parturition and during the next 30 days of lactation were measured. Different multivariate analysis techniques were used to diagnose the disease at very early stage and determine how the spectral properties of milk vary with its composition and animal health. PLS model for prediction of somatic cell count (SCC) based on NIR milk spectra was made. The best accuracy of determination for the 1100-2500nm range was found using smoothed absorbance data and 10 PLS factors. The standard error of prediction for independent validation set of samples was 0.382, correlation coefficient 0.854 and the variation coefficient 7.63%. It has been found that SCC determination by NIR milk spectra was indirect and based on the related changes in milk composition. From the spectral changes, we learned that when mastitis occurred, the most significant factors that simultaneously influenced milk spectra were alteration of milk proteins and changes in ionic concentration of milk. It was consistent with the results we obtained further when applied 2DCOS. Two-dimensional correlation analysis of NIR milk spectra was done to assess the changes in milk composition, which occur when somatic cell count (SCC) levels vary. The synchronous correlation map revealed that when SCC increases, protein levels increase while water and lactose levels decrease. Results from the analysis of the asynchronous plot indicated that changes in water and fat absorptions occur before other milk components. In addition, the technique was used to assess the changes in milk during a period when SCC levels do not vary appreciably. Results indicated that milk components are in equilibrium and no appreciable change in a given component was seen with respect to another. This was found in both healthy and mastitic animals. However, milk components were found to vary with SCC content regardless of the range considered. This important finding demonstrates that 2-D correlation analysis may be used to track even subtle changes in milk composition in individual cows. To find out the right threshold for SCC when used for mastitis diagnosis at cow level, classification of milk samples was performed using soft independent modeling of class analogy (SIMCA) and different spectral data pretreatment. Two levels of SCC - 200 000 cells/$m\ell$ and 300 000 cells/$m\ell$, respectively, were set up and compared as thresholds to discriminate between healthy and mastitic cows. The best detection accuracy was found with 200 000 cells/$m\ell$ as threshold for mastitis and smoothed absorbance data: - 98% of the milk samples in the calibration set and 87% of the samples in the independent test set were correctly classified. When the spectral information was studied it was found that the successful mastitis diagnosis was based on reviling the spectral changes related to the corresponding changes in milk composition. NIRS combined with different ways of spectral data ruining can provide faster and nondestructive alternative to current methods for mastitis diagnosis and a new inside into disease understanding at molecular level.

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