• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.4
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• pp.1223-1247
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• 2012

The need for securing Wireless Sensor Networks (WSNs) is essential especially in mission critical fields such as military and medical applications. Security techniques that are used to secure any network depend on the security requirements that should be achieved to protect the network from different types of attacks. Furthermore, the characteristics of wireless networks should be taken into consideration when applying security techniques to these networks. In this paper, energy efficient Security Model for Tree-based Routing protocols (SMTR) is proposed. In SMTR, different attacks that could face any tree-based routing protocol in WSNs are studied to design a security reference model that achieves authentication and data integrity using either Message Authentication Code (MAC) or Digital Signature (DS) techniques. The SMTR communication and processing costs are mathematically analyzed. Moreover, SMTR evaluation is performed by firstly, evaluating several MAC and DS techniques by applying them to tree-based routing protocol and assess their efficiency in terms of their power requirements. Secondly, the results of this assessment are utilized to evaluate SMTR phases in terms of energy saving, packet delivery success ratio and network life time.

• Geomechanics and Engineering
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• v.36 no.4
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• pp.381-390
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• 2024

The introduction of bio-based materials has been recommended in the geotechnical engineering field to reduce environmental pollutants such as heavy metals and greenhouse gases. However, bio-treated soil methods face limitations in field application due to short research periods and insufficient verification of engineering performance, especially when compared to conventional materials like cement. Therefore, this study aimed to develop a machine learning model for predicting the unconfined compressive strength, a representative soil property, of biopolymer-based soil treatment (BPST). Four machine learning algorithms were compared to determine a suitable model, including linear regression (LR), support vector regression (SVR), random forest (RF), and neural network (NN). Except for LR, the SVR, RF, and NN algorithms exhibited high predictive performance with an R² value of 0.98 or higher. The permutation feature importance technique was used to identify the main factors affecting the strength enhancement of BPST. The results indicated that the unconfined compressive strength of BPST is affected by mean particle size, followed by biopolymer content and water content. With a reliable prediction model, the proposed model can present guidelines prior to laboratory testing and field application, thereby saving a significant amount of time and money.

• Magazine of the Korean Society of Agricultural Engineers
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• v.24 no.1
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• pp.31-43
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• 1982

Engineering phase of dairy housing systems has close connection with the milk produc- tivity of dairy cattle, the quality of milk, extension of dairy production systems, labor- saving in management of dairy cattle and the like. Moreover, the rate of investment of dairy housing facilities is of relatively high level, However, there has been almost no research effort for the improvement of engineering aspects of dairy housing systems in Korea. The purpose of this study is to find out general engineering problems and to recomm- end the improvement in dairy housing systems in Korea. Field survey by means of questionaire, direct measurements, taking pictures and sketching was conducted to get necessary information for the study. Kyung-ki Do region was firstly chosen for sampling area since it has included more than half of the number of dairy farms of the whole country. The results obtained are summarized as follows: 1. In overall dairy farm layout, the dwellings of workers were ignored in the light of sanitary environment 2. The layout of stalls in a dairy barn belongs mostly to the type of double-row face-out, which is compatible with the emphasis of manure disposal activities. 3. While the width and length of stalls were sufficiently close to the standard dimension, the width of mangers was much less than the standard dimension. 4. The width and depth of manure gutters and the width of working alleys were much. less than the standard dimension. 5. The mooring equipment was mostly in the classes of chain or rope. The watering equipment was not facilitated independantly except the one cese of using watercup. 6. The bucket milkers with one or two bucket milkers with the capacity of two cattles. each were used as milking equipment in most dairy farms. 7. There were only few milk rooms independently spaced from other space, in which the arrangement of milking equipment was much less than the standard condition. 8. The lounging ground area was averaged to be sufficient for the activity of dairy herd. 9. Silos for silage used during winter consisted of mostly bunker silos, trench silos and underground vertical silos. Ordinary vertical silos were considered for the farmers to be inconvenient for the labor saving. 10. From the view point of heat conservation and moisture removal within the dairy barns, windows were not flexible for the easy ventilation and ceiling part was not adequate for temperatur maintenance. 11. Waste treatment and disposal systems were not provided with most dairy farms, therefore the livestock waste pollution problems would be serious in the near future.

• Journal of Korean Library and Information Science Society
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• v.52 no.1
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• pp.279-300
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• 2021

The present study aimed to investigate the information needs and information seeking behavior of consumers who attempted to quit or maintain the ceasing of smoking and analyze the effects of the health information obtained at different stages. In particular, we examined how consumers use mobile health applications(health apps) as aids to change unhealthy behaviors and how their use of health apps influence health behavior changes. For 7 months from December 2017 to July 2018, the researchers observed changes in smoking behaviors of college students who use smoking-cessation apps and conducted face-to-face interviews. Regarding the effects of smoking-cessation apps, the participants in the action stage reported that they were encouraged to quit smoking by visualized information such as the number of days of smoking cessation, change of health status, and the saving of money due to smoking cessation. The participants in the maintenance stage highlighted that smoking cessation apps were helpful in recognizing the importance and achievement of smoking cessation by sharing experiences and social support with other attempters in the app community. The study provided theoretical implications in the field of information behavior in that it identified the particular types of information needs and information-seeking behavior of the consumers who were using mobile apps in their behavior modification process. In addition, those findings can contribute to designing the contents of the smoking cessation apps that reflect the information needs of those who attempt to cease smoking and further suggest practical insights to health information services that promote effective information intervention strategies in health behavior change.

• Therapeutic Science for Rehabilitation
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• v.11 no.1
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• pp.35-47
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• 2022

Objective : In this study, we conducted a questionnaire survey of occupational therapists to examine their perceptions on and willingness to provide telerehabilitation dementia prevention education. Methods : From March 13 to 19, 2021, a questionnaire survey targeting occupational therapists in Busan, Ulsan, and Gyeongnam was conducted. 100 questionnaires were distributed but only 70 were collected. The collected data were subjected to frequency analysis and descriptive statistics using the statistical program SPSS version 23.0. Results : The average scores by region were as follows. The average compatibility score was highest at 3.92 score, intention to providing education, doctors 3.89 score, community-centric rehabilitation awareness 3.81 score, cost saving 3.78 score, perceiver usefulness 3.75 score, accessibility 3.62 score, the quality of telerehabilitation service was in order of 3.49 score. Conclusion : All items asking whether occupational therapists participate in community-centered rehabilitation and non-face-to-face dementia prevention education programs showed high scores, indicating the willingness to participate actively. In the future, in addition to follow-up research on the implementation of telerehabilitation dementia prevention education, measures for improving accessibility within the local and national government should be discussed.

• Archives of Craniofacial Surgery
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• v.10 no.2
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• pp.71-75
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• 2009

Purpose: Recently, orbital wall fracture is common injuries in the face. Facial CT is essential for the accurate diagnosis and appropriate treatment to reconstruct of the orbital wall. The objective of this study was to report the method for accurate measurement of area and shape of the bony defect in the blow-out fractures using facial CT in prior to surgery. Methods: The authors experienced 46 cases of orbital wall fractures and examined for diplopia, sensory disturbance in the area of distribution of the infraorbital nerve, and enophthalmos in the preoperation and followed 1 months after surgery, from August 2007 to May 2008. Bony defect was predicted by measuring continuous defect size from 3 mm interval facial CT. Copying from the defect model (template), we reconstructed orbital wall with resorbable sheet (Inion $CPS^{(R)}$ Inion Oy, Tampere, Finland). Results: One months after surgery using this method, 26 (100%) of the 26 patients improved in the diplopia and sensory disturbance in the area of distribution of the infraorbital nerve. Also 8 (72.7%) of the 11 patients had enophthalmos took favorable turn. Conclusion: This accurate and time-saving method is practicable for determining the location, shape and size of the bony defect. Using this method, we can reconstruct orbital wall fracture fastly and precisely.

• International Commerce and Information Review
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• v.18 no.4
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• pp.221-262
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• 2016

This study examines the dispute resolution culture and negotiation strategy in Vietnam. We adopt area studies methodology in order to analyze dispute resolution and negotiation strategy in Vietnam, since the dispute resolution and negotiation strategy are keenly connected with the culture, law, institution, and economic system of the society. Our findings are as follows. First, Vietnamese society has the culture that has the characteristics of maternal society and patrilineal society. Vietnamese women has traditionally participated in the economic activity. Second, Vietnamese people showed loyalty to the nation. Third, Vietnamese society is shown to belong to the culture of collectivism. In addition, we investigate the multi-faced characteristics of Vietnamese dispute resolution culture and negotiation strategy. Our findings are as follows. First, Vietnamese people utilize middlemen in implementing dispute resolution and negotiation. Second, Vietnamese people prefer long-term negotiation style. Third, Vietnamese people is accustomed to face-saving culture. Fourth, Vietnamese people prefer the indirect communication style. Fifth, Vietnamese people prefer written document instead of oral agreement in contract. Sixth, Vietnamese people and firms prefer ADR to formal law.

• Informatization Policy
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• v.21 no.3
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• pp.102-127
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• 2014

Although mobile banking provides cost-saving opportunities as well as convenient banking experience for customers, today's banks still face challenges when deploying the technology because a good number of customers are reluctant to use mobile banking for personal reasons. This paper is an empirical investigation of the determinants of the intention to use smartphone-based mobile banking services. The determinants are grouped into two categories including personal factors and social influence factors. We conducted an empirical analysis using 751 survey responses collected from present users of mobile banking services. The results of the analysis reveal that all the personal factors have positive relationships with the intention to use mobile banking services. On the other hand, it was found that of the social influence factors, perceived herding behavior has significantly positive relationship with the intention to use smartphone-based services, whereas subjective norm is not significantly related to the intention. We provide practical as well as academic implications of the research findings.

• Composites Research
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• v.24 no.4
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• pp.17-22
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• 2011

In this paper, as a basic research to apply the composite sandwich to underwater vehicle, the manufacturing, analysis and test methods, and weight saving effect of a composite sandwich cylinder under external pressure were studied. A two-step manufacturing method to prevent the wrinkling of the sandwich cylinder face was proposed and the three cylinders were made and tested. Finite element results based on the shell and solid model using MSC.Nastran were compared with test results. The comparison showed that the linear finite element analysis using the shell and solid elements can predict the buckling pressure of the sandwich cylinder with approximately 3% difference. The parametric study of the filament wound cylinders revealed that the composite sandwich can reduce the weight of the cylinder more than 30% compared with the filament wound cylinder supporting the same pressure.

• Journal of Korea Spatial Information System Society
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• v.6 no.2 s.12
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• pp.39-49
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• 2004

An increasing number of distributed applications will be achieved with mobile technology. These applications face temporary loss of network connectivity when they move. They need to discover other hosts in an ad-hoc manner, and they are likely to have scarce resources including CPU speed, memory and battery power. Software engineers building mobile applications need to use a suitable middleware that resolves these problems and offers appropriate support for developing mobile applications. In this paper, we describe the meta-server building for middleware that addresses reflective context awareness and present usability with demonstration. Metadata is consist of user configuration, device configuration, user context, device context and dynamic image metadata. When middleware send a saving or retrieval request to meta-server, it returns messages to middleware after the verification of the request. This meta-server has the application for multimedia stream services with context awareness.