• International Journal of Contents
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• 제15권4호
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• pp.27-35
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• 2019

In this paper, we propose an advanced Minimum Mean Square Error (MMSE) channel estimation method for IEEE 802.11p/Wireless Access in Vehicular Environments (WAVE) systems. To improve the performance of MMSE method, we apply the Weighted Sum using Update Matrix (WSUM) scheme to the step of calculating the instantaneously estimated channel and then, a time domain selectively averaging method is applied after the WSUM scheme. Based on that, the accuracy of instantaneously estimated channel increases and then, the accuracy of auto covariance matrix also increases. Consequently, we can achieve the performance gain over the conventional MMSE method. Through simulations based on the IEEE 802.11p standard, it is confirmed that the proposed scheme can outperform the existing channel estimation schemes.

• 한국유기농업학회지
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• 제16권4호
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• pp.391-408
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• 2008

The overall focus of this study was to identify marketing and promotion strategies that can maintain and enhance environmentally friendly farm and organic production and processing activities. This is particularly important as the volume of environmentally friendly farm and organic produce that is generally available is increasing, and significant players, such as Organic Marketing Initiatives(OMI) and conventional marketing co-operatives, are becoming involved in the market. The rapid increase in production of environmentally friendly farm products and organic food is creating new and more complex challenges for marketing, from vegetable box schemes large co-operatives supplying the precise quality and volume required by supermarkets. A possible strategy for many farmers is to co-operate in regionally or nationally operating marketing initiatives. The main objective of any public relations(PR) activity should to enhance publicity and to improve an OMIs image. No promotion, no perception of OMI performance.

• Korean Journal of Hydrosciences
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• 제8권
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• pp.41-56
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• 1997

A new routing computer model for the symmetric compound channel called the ASRMCS(Apparent Shear Force Muskingum-Cunge Method in Symmetry) has been developed. The Muskingum-Cunge routing method is adapted. The Apparent Shear Force (ASF) between the deep main channel and the shallow floodplan flow is introduced while the flow is routed. The nonlinear parameter method is applied. The temporal and spatial increments are varied according to the flow rate. The adaptation of above schemes is tested against the routed hydrographs using the DAMBRK model. The results of general routing practice of Muskingum-Cunge Method(GPMC) are also compared with those of above two models. The results of the new model match remarkably well with those of DAMBRK. The routed hydrographs show a smooth variation from the inflow boundary condition without any distortions caused by the difference of cross-section shape. However, the results of GPMC, showing early rise and fall of routed hydrograph, have considerable differences from those of the ASFMCS and DAMBRK.

• 식품보건융합연구
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• 제5권4호
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• pp.19-23
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• 2019

In recent years, the Internet was a lot of information on the use of Tesla coils bifilar [1] in conjunction with induction cooker, for "free" electricity during power resistive load, including different incandescent lamps. With the development of scientific and technological progress, the demand for electricity in each year is increasing, and at the same time, the need to increase the capacity of electricity production, which entails large investments and, consequently, increase of prices for consumers. As before today, the search for free electric energy is an up-to-date and still open topic. The purpose of research - simplification of information on the possibility of using bifilar coils as an electric current source in conjunction with induction cooker. Consequently, it can be concluded from the above that the use of Tesla coils in combination with induction cooker has very low k.k.d. and it is not possible to obtain excessive electric energy using the Tesla coil under the connection schemes considered.

• 가정과삶의질연구
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• 제32권5호
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• pp.31-40
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• 2014

The purpose of this study is to investigate low- and middle-income preschoolers' use of contextualized and decontextualized talk. The contextualized and decontextualized talk of 70 five-year-old children were analyzed by children's gender and their socioeconomic status. The participants, as dyads, participated in a peer play session for 10 minutes. The play sessions were videotaped and the videotaped data were transcribed. Each transcript was analyzed according to the modified version of Curenton et al. (2008)'s coding schemes. The results showed that children from middle-income families engaged more in both contextualized and decontextualized talk than children from low-income families. Also, girls from middle-income families engaged in more contextualized-decontextualized talk(psychological states) than girls from low-income families.

• Journal of Positioning, Navigation, and Timing
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• 제5권1호
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• pp.37-45
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• 2016

In this paper, design and implementation issues for a network-oriented RF emitter localization system with array antenna are discussed. For hardware, the problem of array mismatch and RF/IF channel mismatch are introduced and the calibration schemes for solving those problems are also provided. For software, it is explained how to overcome the drawback of conventional MUltiple Signal Identification and Classification (MUSIC) algorithm in a point of identifying the number of received signals and problems such as Data Association Problem and Ghost Node Problem in regard to multiple emitter localization are presented with some approaches for getting around those problems. Finally, for implementation, a criterion for arranging each of sensors and a requirement for alignment of array antenna' orientation are also given.

• 한국정보시스템학회지:정보시스템연구
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• 제8권1호
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• pp.109-129
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• 1999

This study deals with the problem of information dissemination in a communication network, which is defined to be the process whereby a set of messages, generated by an originator, is transmitted to all the members within the network. Since this type of message generally includes control data to manage the network or global information that all members should know, it is to be required to transmit it to all the members as soon as possible. In this study, it is assumed that a member can either transmit or receive a message and an informed member can transmit it to only one of its neighbors at time. This type of transmission is called 'local broadcasting' Several schemes of call sequencing are designed for a general-type network with nonuniform edge transmission times, and then computer simulations are performed. Some heuristics for information dissemination are proposed and tested. For this, optimal call sequence in a tree-type network, sequencing theory and graph theory are applied. The result shows that call sequencing based on the shortest path tree is the most desirable.

• International Journal of Contents
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• 제9권3호
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• pp.29-34
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• 2013

This study attempted to compare usability of auditory interfaces, which is a comprehensive concept that includes safety, utility, effectiveness, and efficiency, in personal computing environments: verbal messages (speech sounds), earcons (musical sounds), and auditory icons (natural sounds). This study hypothesized that verbal messages would offer higher usability than earcons and auditory icons, since the verbal messages are easy to interpret and understand based on semiotic process. In this study, usability was measured by a set of seven items: ability to inform what the program is doing, relevance to visual interfaces, degree of stimulation, degree of understandability, perceived time pressure, clearness of sound outputs, and degrees of satisfaction. Through the experimental research, the results showed that verbal messages provided the highest level of usability. On the contrary, auditory icons showed the lowest level of usability, as they require users to establish new coding schemes, and thus demand more mental effort from users.

• International Journal of Contents
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• 제12권2호
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• pp.37-41
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• 2016

In this paper, we propose a friend recommendation scheme that takes into consideration the attribute information of a POI and a user's movement patterns. The proposed scheme broadly consists of a part that filters out other users who have different preferences by calculating preferences using the attribute information of users and a part that finds a moving trajectory close to that of a user with a pattern-matching scheme. To verify the superiority of the proposed scheme, we compare it with existing schemes through various performance evaluations.

• 무역학회지
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• 제44권2호
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• pp.37-49
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• 2019

This paper determines if mandated alcohol health information labelling could be an obstacle to international trade by discussing international trade rules affecting member nations. WTO members could use alcohol labelling rules to protect human health, reduce the consumption of alcohol and provide product information. When a member uses alcohol labelling as a technical regulation or standard, it should comply with TBT Articles 2.2 and 2.4. If a member uses some specific warning messages for their objectives, it should be considered the contribution of the measure, trade restrictiveness, and alternatives. If WTO members want to employ their own alcohol labelling schemes for addressing carcinogenicity, intoxicating effects, dependence potential, effects on children, adolescents and pregnancy, it could be a technical barrier and also create adverse effects on international trade. Therefore, the harms of alcohol are supported by scientific evidence, and for this reason, the international harmonization for alcohol labelling should be discussed openly to prevent negative effects on trade.