A Study on the Extraction of a River from the RapidEye Image Using ISODATA Algorithm (ISODATA 기법을 이용한 RapidEye 영상으로부터 하천의 추출에 관한 연구)
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- Journal of the Korean Association of Geographic Information Studies
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- v.15 no.4
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- pp.1-14
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- 2012
A river is defined as the watercourse flowing through its channel, and the mapping tasks of a river plays an important role for the research on the topographic changes in the riparian zones and the research on the monitoring of flooding in its floodplain. However, the utilization of the ground surveying technologies is not efficient for the mapping tasks of a river due to the irregular surfaces of the riparian zones and the dynamic changes of water level of a river. Recently, the spatial information data sets are widely used for the coastal mapping tasks due to the acquisition of the topographic information without human accessibility. In this research, we tried to extract a river from the RapidEye imagery by using the ISODATA(Iterative Self_Organizing Data Analysis) classification algorithm with the two different parameters(NIR (Near Infra-Red) band and NDVI(Normalized Difference Vegetation Index)). First, the two different images(the NIR band image and the NDVI image) were generated from the RapidEye imagery. Second, the ISODATA algorithm were applied to each image and each river was generated in each image through the post-processing steps. River boundaries were also extracted from each classified image using the Sobel edge detection algorithm. Ground truths determined by the experienced expert are used for the assessment of the accuracy of an each generated river. Statistical results show that the extracted river using the NIR band has higher accuracies than the extracted river using the NDVI.
The purpose of this study was to investigate drug abuse and to find related factors among high school students. The subjects for this study were 973 students from 10 high schools in Taegu city. The data were collected from September 30, 1996 to October 30, 1996. The questionnaire developed by Kim Soyoaja (1991) surveyed adolescent drug use and questions on smoking and drinking were readjusted and added by the researcher based on review. The data was analyzed using frequency, percentage,
The categories of national health problems may be mainly divided into health promotion, problems of diseases, and population-economic problems which are indirectly related to health. Of them, the problems of diseases will be exclusively dealt with this speech. Rurality and Disease Problems There are many differences between rural and urban areas. In general, indicators of rurality are small size of towns, dispersion of the population, remoteness from urban centers, inadequacy of public transportation, poor communication, inadequate sanitation, poor housing, poverty, little education lack of health personnels and facilities, and in-accessibility to health services. The influence of such conditions creates, directly or indirectly, many problems of diseases in the rural areas. Those art the occurrence of preventable diseases, deterioration and prolongation of illness due to loss of chance to get early treatment, decreased or prolonged labour force loss, unnecessary death, doubling of medical cost, and economic loss. Some Considerations of Innovative Approach The followings art some considerations of innovative approaches to the problems of diseases in the rural Korea. 1. It would be essential goal of the innovative approaches that the damage and economic loss due to diseases will be maintained to minimum level by minimizing the absolute amount of the diseases, and by moderating the fee for medical cares. The goal of the minimization of the disease amount may be achieved by preventive services and early treatment, and the goal of moderating the medical fee may be achieved by lowering the prime cost and by adjusting the medical fees to reasonable level. 2. Community health service or community medicine will be adopted as a innovative means to disease problems. In this case, a community is defined as an unit area where supply and utilization of primary service activities can be accomplished within a day. The essential nature o the community health service should be such activities as health promotion, preventive measures, medical care, and rehabilitation performing efficiently through the organized efforts of the residents in a community. Each service activity should cover all members of the residents in a community in its plan and performance. The cooperation of the community peoples in one of the essential elements for success of the service program, The motivations of their cooperative mood may be activated through several ways: when the participation of the residents in service program of especially the direct participation of organized cooperation of the area leaders art achieved through a means of health education: when the residents get actual experience of having received the benefit of good quality services; and when the health personnels being armed with an idealism that they art working in the areas to help health problems of the residents, maintain good human relationships with them. For the success of a community health service program, a personnel who is in charge of leadership and has an able, a sincere and a steady characters seems to be required in a community. The government should lead and support the community health service programs of the nation under the basis of results appeared in the demonstrative programs so as to be carried out the programs efficiently. Moss of the health problems may be treated properly in the community levels through suitable community health service programs but there might be some problems which art beyond their abilities to be dealt with. To solve such problems each community health service program should be under the referral systems which are connected with health centers, hospitals, and so forth. 3. An approach should be intensively groped to have a physician in each community. The shortage of physicians in rural areas is world-wide problem and so is the Korean situation. In the past the government has initiated a system of area-limited physician, coercion, and a small scale of scholarship program with unsatisfactory results. But there might be ways of achieving the goal by intervice, broadened, and continuous approaches. There will be several ways of approach to motivate the physicians to be settled in a rural community. They are, for examples, to expos the students to the community health service programs during training, to be run community health service programs by every health or medical schools and other main medical facilities, communication activities and advertisement, desire of community peoples to invite a physician, scholarship program, payment of satisfactory level, fulfilment of military obligation in case of a future draft, economic growth and development of rural communities, sufficiency of health and medical facilities, provision of proper medical care system, coercion, and so forth. And, hopefully, more useful reference data on the motivations may be available when a survey be conducted to the physicians who are presently engaging in the rural community levels. 4. In communities where the availability of a physician is difficult, a trial to use physician extenders, under certain conditions, may be considered. The reason is that it would be beneficial for the health of the residents to give them the remedies of primary medical care through the extenders rather than to leave their medical problems out of management. The followings are the conditions to be considered when the physician extenders are used: their positions will be prescribed as a temporary one instead of permanent one so as to allow easy replacement of the position with a physician applicant; the extender will be under periodic direction and supervision of a physician, and also referral channel will be provided: legal constraints will be placed upon the extenders primary care practice, and the physician extenders will used only under the public medical care system. 5. For the balanced health care delivery, a greater investment to the rural areas is needed to compensate weak points of a rurality. The characteristics of a rurality has been already mentioned. The objective of balanced service for rural communities to level up that of urban areas will be hard to achieve without greater efforts and supports. For example, rural communities need mobile powers more than urban areas, communication network is extremely necessary at health delivery facilities in rural areas as well as the need of urban areas, health and medical facilities in rural areas should be provided more substantially than those of urban areas to minimize, in a sense, the amount of patient consultation and request of laboratory specimens through referral system of which procedures are more troublesome in rural areas, and more intensive control measures against communicable diseases are needed in rural areas where greater numbers of cases are occurred under the poor sanitary conditions.
I. Research Objectives: Most of the previous studies on diffusion have concentrated on efficacy of WOM communication with the use of variables at individual level (Iacobucci 1996; Midgley et al. 1992). However, there is a paucity of studies which investigated network's structural properties as antecedents of WOM from the perspective of consumers' sociocultural propensities. Against this research backbone, this study attempted to link the network's structural properties and consumer' WOM behavior on cross-national basis. The major research objective of this study was to examine the relationship between network properties and WOM by comparing Korean and Chinese consumers. Specific objectives of this research are threefold; firstly, it sought to examine whether network properties (i.e., tie strength, centrality, range) affect WOM (WOM intention and quality of WOM). Secondly, it aimed to explore the moderating effects of cutural orientation (uncertainty avoidance and individuality) on the relationship between network properties and WOM. Thirdly, it substantiates the role of innovativeness as antecedents to both network properties and WOM. II. Research Hypotheses: Based on the above research objectives, the study put forth the following research hypotheses to validate.
This study is to empirically examine the primary dimensions of visual merchandising (VMD) of internet shopping mall, namely store design, merchandise, and merchandising cues, to be a attractive virtual store to the shoppers. The authors reviewed the literature related to the major components of VMD from the perspective of the AIDA model, which has been mainly applied to the offline store settings. The major purposes of the study are as follows; first, tries to derive the variables related with the components of visual merchandising through reviewing the existing literatures, establish the hypotheses, and test it empirically. Second, examines the relationships between the components of VMD and the attitude toward the VMD, however, putting more emphasis on finding out the component structure of the VMD. VMD needs to be examined with the perspective that an online shopping mall is a virtual self-service or clerkless store, which could reduce the number of employees, help the shoppers search, evaluate and purchase for themselves, and to be explored in terms of the in-store persuasion processes of customers. This study reviewed the literatures related to store design, merchandise, and merchandising cues which might be relevant to the store, product, and promotion respectively. VMD is a total communication tool, and AIDA model could explain the in-store consumer behavior of online shopping. Store design has to do with triggering a consumer attention to the online mall, merchandise with a product related interest, and merchandising cues with promotions such as recommendation and links that induce the desire to pruchase. These three steps might be seen as the processes for purchase actions. The theoretical rationale for the relationship between VMD and AIDA could be found in Tyagi(2005) that the three steps of consumer-oriented merchandising are a store, a product assortment, and placement, in Omar(1999) that three types of interior display are a architectural design display, commodity display, and point-of-sales(POS) display, and in Davies and Ward(2005) that the retail store interior image is related to an atmosphere, merchandise, and in-store promotion. Lee et al(2000) suggested as the web merchandising components a merchandising cues, a shopping metaphor which is an assistant tool for search, a store design, a layout(web design), and a product assortment. The store design which includes differentiation, simplicity and navigation is supposed to be related to the attention to the virtual store. Second, the merchandise dimensions comprising product assortments, visual information and product reputation have to do with the interest in the product offerings. Finally, the merchandising cues that refer to merchandiser(MD)'s recommendation of products and providing the hyperlinks to relevant goods for the shopper is concerned with attempt to induce the desire to purchase. The questionnaire survey was carried out to collect the data about the consumers who would shop at internet shopping malls frequently. To select the subject malls, the mall ranking data announced by a mall rating agency was used to differentiate the most popular and least popular five mall each. The subjects was instructed to answer the questions after navigating the designated mall for five minutes. The 300 questionnaire was distributed to the consumers, 166 samples were used in the final analysis. The empirical testing focused on identifying and confirming the dimensionality of VMD and its subdimensions using a structural equation modeling method. The confirmatory factor analysis for the endogeneous and exogeneous variables was carried out in four parts. The second-order factor analysis was done for a store design, a merchandise, and a merchandising cues, and first-order confirmatory factor analysis for the attitude toward the VMD. The model test results shows that the chi-square value of structural equation is 144.39(d.f 49), significant at 0.01 level which means the proposed model was rejected. But, judging from the ratio of chi-square value vs. degree of freedom, the ratio was 2.94 which smaller than an acceptable level of 3.0, RMR is 0.087 which is higher than a generally acceptable level of 0.08. GFI and AGFI is turned out to be 0.90 and 0.84 respectively. Both NFI and NNFI is 0.94, and CFI 0.95. The major test results are as follows; first, the second-order factor analysis and structural equational modeling reveals that the differentiation, simplicity and ease of identifying current status of the transaction are confirmed to be subdimensions of store design and to be a significant predictors of the dependent variable. This result implies that when designing an online shopping mall, it is necessary to differentiate visually from other malls to improve the effectiveness of the communications of store design. That is, the differentiated store design raise the contrast stimulus to sensory organs to promote the memory of the store and to have a favorable attitude toward the VMD of a store. The results that navigation which means the easiness of identifying current status of shopping affects the attitude to VMD could be interpreted that the navigating processes via the hyperlinks which is characteristics of an internet shopping is a complex and cognitive process and shoppers are likely to lack the sense of overall structure of the store. Consequently, shoppers are likely to be alost amid shopping not knowing where to go. The orientation tool enhance the accessibility of information to raise the perceptive power about the store environment.(Titus & Everett 1995) Second, the primary dimension of merchandise and its subdimensions was confirmed to be unidimensional respectively, have a construct validity, and nomological validity which the VMD dimensions supposed to have a positive correlation with the dependent variable. The subdimensions of product assortment, brand fame and information provision proved to have a positive effect on the attitude toward the VMD. It could be interpreted that the more plentiful the product and brand assortment of the mall is, the more likely the shoppers to favor it. Brand fame and information provision as well affect the VMD attitude, which means that the more famous the brand, the more likely the shoppers would trust and feel familiar with the mall, and the plentifully and visually presented information could have the shopper have a favorable attitude toward the store VMD. Third, it turned out to be that merchandising cue of product recommendation and hyperlinks affect the VMD attitude. This could be interpreted that recommended products could reduce the uncertainty related with the purchase decision, and the hyperlinks to relevant products would help the shopper save the cognitive effort exerted into the information search and gathering, which could lead to a favorable attitude to the VMD. This study tried to sheds some new light on the VMD of online store by reviewing the variables mentioned to be relevant with offline VMD in the existing literatures, and tried to link the VMD components from the perspective of AIDA model. The effect size of the VMD dimensions on the attitude was in the order of the merchandise, the store design and the merchandising cues.It is said that an internet has an unlimited place for display, however, the virtual store is not unlimited since the consumer has a limited amount of cognitive ability to process the external information and internal memory. Particularly, the shoppers are likely to face some difficulties in decision making on account of too many alternative and information overloads. Therefore, the internet shopping mall manager should take into consideration the cost of information search on the part of the consumer, to establish the optimal product placements and search routes. An efficient store composition would be possible by reducing the psychological burdens and cognitive efforts exerted to information search and alternatives evaluation. The store image is in most part determined by the product category and its brand it deals in. The results of this study support this proposition that the merchandise is most important to the VMD attitude than other components, the manager is required to take a strategic approach to VMD. The internet users are getting more accustomed and more knowledgeable about the internet media and more likely to accept the internet as a shopping channel as the period of time during which they use the internet to shop become longer. The web merchandiser should be aware that the product introduction using a moving pictures and a bulletin board become more important in order to present the interactive product information visually and communicate with customers more actively, therefore leading to making the quantity and quality of product information more rich.