• Journal of the Institute of Convergence Signal Processing
• /
• v.23 no.4
• /
• pp.228-233
• /
• 2022

This study is an experimental study on how to use phase change materials(PCM) to generate electrical energy for long-term operation of underwater unmanned vehicles. The electrical energy generation method is a volume change and a pressure change that occur as a phase change material changes to a solid or liquid state according to temperature, and the change in pressure creates a flow of fluid to create electrical energy. Polyethylene glycol was used as a phase change material considering the temperature of the ocean. In addition, an electrical energy generating device that converts volume change into pressure at low temperature (1℃~2℃) in solid state and high temperature (21℃~25℃) in liquid state was fabricated. As a result of the experiment, the pressure change according to the phase change rapidly changed between 1 hour and 2 hours, and maintained a pressure of about 24MPa after 4 hours. Through this, it was confirmed that it can be used as a power source for underwater unmanned vehicles using phase change materials and temperature differences. In addition, it was found that a more improved design should be made in order to apply the phase change material to an underwater unmanned vehicle.

• Journal of Service Research and Studies
• /
• v.13 no.2
• /
• pp.24-40
• /
• 2023

As the aversion to advertising grows, native advertising has gained significant attention as a means to counteract this rejection. Native advertising is designed to seamlessly blend with other content on the page where they are displayed. They mimic the overall design and presentation of the platform, providing a natural exposure to consumers. Many companies utilize native advertising, but there is not much academic research on this topic. Therefore this study aims to examine the effectiveness of native advertising for social issues. The study looked at two types of native advertising: ads created by a company and ads sponsored by a company. Results suggested that consumers showed more positive attitudes towards a company's ads if they were sponsored by the company rather than created by the company. This study argued that this effect would be more pronounced for consumers who tended to buy ethically. To verify these hypotheses an online experiment was conducted revealing that on average consumers displayed the same attitude toward a company whether the native advertising was created or sponsored by a company. However, it was also discovered that consumers with a tendency for ethical consumerism formed more positive attitudes toward companies when the company sponsored native advertising as opposed to having created it. In practice, this study suggests how companies can improve the effectiveness of native advertising, such as implementing native advertising as a sponsor and being transparent about their advertising to appeal to consumers with high ethical consumption tendencies. This study expands the scope of research in areas related to native adverting and corporate social responsibilities.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2011.04a
• /
• pp.576-579
• /
• 2011

Wireless sensor network are widely all over different fields. Because of its distinguished characteristics, we must take account of the factor of energy consumed when designing routing protocol. Wireless sensor networks consist of small battery powered devices with limited energy resources. Once deployed, the small sensor nodes are usually inaccessible to the user, and thus replacement of the energy source is not feasible. Hence, energy efficiency is a key design issue that needs to be enhanced in order to improve the life span of the network. In BCDCP, all sensors sends data from the CH (Cluster Head) and then to the BS (Base Station). BCDCP works well in a smallscale network however is not preferred in a large scale network since it uses much energy for long distance wireless communication. TBRP can be used for large scale network, but it weakness lies on the fact that the nodedry out of energy easily since it uses multi-hops transmission data to the Base Station. Here, we proposed a routing protocol. A Cluster Based Energy Efficient Tree Routing Protocol (CETRP) in Wireless Sensor Networks (WSNs) to prolong network life time through the balanced energy consumption. CETRP selects Cluster Head of cluster tree shape and uses maximum two hops data transmission to the Cluster Head in every level. We show CETRP outperforms BCDCP and TBRP with several experiments.

• Journal of Appropriate Technology
• /
• v.5 no.1
• /
• pp.18-24
• /
• 2019

Citarum river in West Java, Indonesia plays strategic roles for Jakarta metropolitan areas. Besides it provides major source of water supply such as domestics and drinking water including Jakarta, it also provides water for hundreds of industries through its cascade reservoirs. However, recently, Citarum river basin has been seriously suffering from water and groundwater pollution as well as the lowering-down of groundwater level due to the extreme use of water resources in dry season by domestic and industrial activities. This project objectives are design and installation of industrial wastewater treatment/recycle facilities to overcome the problem of water pollution and the lowering-down of groundwater level in Bandung. For these, cyclone type dissolved air flotation (DAF), CYFLOAT, was successfully installed as the appropriate technology for the target textile industry with 100 ton/day of capacity. The CYFLOAT system can remove the 96.8% of particulates, which are known as a critical factor to recycle the wastewater, within 40 min of residence time. Furthermore, The CYFLOAT system can reduce the operational cost and land use. The project was carried out in strong partnership with local institute including UNPAR, IBT, and PUSKIM for the sustainability of the technology to textile industry complex in Indonesia.

• Korean Journal of Heritage: History & Science
• /
• v.56 no.2
• /
• pp.28-45
• /
• 2023

Although we have entered the era of digital transformation, there is currently no system that efficiently collects, manages, integrates, and services a large number of archaeological digital source materials produced as a result of cultural relics research, i.e., an intelligent integrated management and service platform for archaeological academic information. In this regard, the need to build a digital dictionary of Korean archaeology was confirmed by examining the problem of the Digital Encyclopedia of Korean Archaeology, which is currently available in PDF format on the web, the current status of the publication and use of the Dictionary of Korean Archaeology, and the cases of building digital platforms at home and abroad. Therefore, this paper aims to suggest a general direction for creating a digital encyclopedia of Korean archaeology based on the Dictionary of Korean Archaeology, which includes quality knowledge information, to reconsider the accessibility of archaeological data in conformity with data access limitations. The application of the series Dictionary of Korean Archaeology, published since 2001, and the necessity for digital transformation were examined, as well as the application of data from the archaeological data archiving platforms of Europe, the USA, Japan, and cases of establishing platforms corresponding to specialized encyclopedias from Korea. Based on these, a three-step implementation plan and detailed projects were suggested to create the Digital Encyclopedia of Korean Archaeology. Through this, we proposed the design of metadata for computerized records and the expansion to semantic (meaning-based) data that gives and shows the relationship information between the produced metadata as the implementation tasks to build the Digital Dictionary of Korean Archaeology. It is hoped that such research will help create an integrated intelligent management and service platform for archaeology, raise awareness, and provide a better understanding of Korean archaeology to the general public.

• The Korean Journal of Franchise Management
• /
• v.9 no.3
• /
• pp.7-18
• /
• 2018

Purpose - Consumers have a variety of strategies to find information about restaurants they want to visit. Consumers can search for and use information from a variety of sources before purchasing a product or service. The development of the Internet has made that consumers could access various informations easily. Therefore, this study classified commercial information provided by restaurants, public information shared by other unknown consumers, and personal information shared by customers' personal experiences or friends/family. This study is information sources influence on enjoyment, attitude and visit intention. Research design, data, methodology - In order to verify the research hypothesis, this study created questionnaires for each variable. Hypothesis analysis data were collected through surveys. In order to develop research hypotheses for this study, the scales was developed. The survey was conducted by an online survey company. Among the online panels owned by survey company, those who have visited restaurants through at least one of the 11 sources provided in this study within the last 3 months were surveyed. The survey period was 10 days from March 5 to 14, 2017. A total of 1,500 e-mails and messages were sent back to 301 of them, and 288 were used for analysis except for 13 missing responses. The data was analyzed by using SPSS 21.0 and AMOS 21.0. Results - As a result of analysis, commercial and personal information have a positive effect on enjoyment, but general information did not affect enjoyment. In addition, personal information has a positive effect on attitude, but commercial information and general information did not affect attitude. It was found that commercial information influenced attitude by mediation of pleasure, and pleasure had no significant effect on visit intention. Finally, attitude has a significant effect on visit intention. Conclusions - The restaurant needs to provide accurate information through its homepage or brochure. Accurate information that is not exaggerated can save customers's the cost of believing on a restaurant and the cost of searching for other information. The restaurant which provides unfaithful advertisement would be excluded from customer's choice because customers perceive it as a unreliable restaurant. The marketing of restaurant should be carried out through customer-oriented for the visit of customers. And restaurants need to provide optimized services to their first-time customers in order to increase their revisit.

• The Korean Journal of Franchise Management
• /
• v.9 no.4
• /
• pp.21-31
• /
• 2018

Purpose - Recently, the franchise business has made remarkable progress, but many conflicts have occurred. From this perspective, this paper explains how to improve the long - term relationship between franchisor and franchisee by integrating the relationship between franchisor of franchise business and franchisee. This study aims to identify the franchisee's economic and social satisfaction and to examine their influences on calculative and affective commitment, and loyalty. At the end of this paper, theoretical and managerial implication were suggested. Research design, data, and methodology - The data were collected from owners and store managers in franchisees located in Seoul, Korea. The trained researchers contacted owners and managers of the franchise stores. The questionaires were distributed to owners and managers consented to respond. The collected questionnaires were used for the final analysis of 324 copies(243 store owners and 81 store managers), except for 26 copies of the untrustworthy response out of 350 copies. The data were analyzed with SPSS, 21.0 and SmartPls 3.0 Result - The results of the study are as follows. First, economic satisfaction effects both calculative and affective commitment, but social satisfaction does not. Second, both calculative and affective commitment have positive effects on loyalty. Third, economic satisfaction has a positive impact on loyalty, but social satisfaction does not. Conclusions - The implications of this study are following as: From the theoretical perspective, this study analyze the satisfaction and commitment of the franchisee from the multidimensional perspective by analyzing the effects of the franchisee on two dimensions of economic and social satisfaction and on calculative and affective commitment. That is, this study explains the trade-off between economica and social satisfaction, and between calculative and affective commitment. From the managerial perspective, the results of this study suggest that the economic satisfaction of the franchise headquarters felt by franchisees should be prioritized over social satisfaction. Especially at the early stage of the contract, economic satisfaction should be given priority over social satisfaction. However, since affective and calculative commitment have a significant effect on loyalty, social satisfaction factors should not be excluded by focusing on only economic ones. In other words, the franchisors should not only think of franchisees as a source of sales and profits, but should respect franchisees and maintain loyal relationships with friends.

• Journal of Bio-Environment Control
• /
• v.32 no.3
• /
• pp.181-189
• /
• 2023

Hydrogen has gained attention as an environmentally friendly energy source among various renewable options, however, its application in agriculture remains limited. This study aims to apply the hydrogen fuel cell triple heat-combining system, originally not designed for greenhouses, to greenhouses in order to save energy and reduce greenhouse gas emissions. This system can produce heating, cooling, and electricity from hydrogen while recovering waste heat. To implement a hydrogen fuel cell triple heat-combining system in a greenhouse, it is crucial to evaluate the greenhouse's heating and cooling load. Accurate analysis of these loads requires considering factors such as greenhouse configuration, existing heating and cooling systems, and specific crop types being cultivated. Consequently, this study aimed to estimate the cooling and heating load using building energy simulation (BES). This study collected and analyzed meteorological data from 2012 to 2021 for semi-enclosed greenhouses cultivating tomatoes in Jeonju City. The covering material and framework were modeled based on the greenhouse design, and crop energy and soil energy were taken into account. To verify the effectiveness of the building energy simulation, we conducted analyses with and without crops, as well as static and dynamic energy analyses. Furthermore, we calculated the average maximum heating capacity of 449,578 kJ·h^-1 and the average cooling capacity of 431,187 kJ·h^-1 from the monthly maximum cooling and heating load analyses.

• Journal of Environmental Health Sciences
• /
• v.49 no.3
• /
• pp.134-148
• /
• 2023

Background: The conducting of health effect surveys (HESs) in environmentally contaminated vulnerable areas (ECVAs) by the central and local governments has been increasing apace with the increase in demand for HESs since the Environmental Health Act was enacted in South Korea in 2008. Objectives: This study aimed to review the HESs of residents in ECVAs conducted in South Korea. Methods: An analysis was performed on 125 reports obtained from the Environment Digital Library, PRISM, and local government websites after selecting from 803 projects obtained as ECVAs from the Korea ON-Line E-Procurement System (1997~2021), National Institute Environment Research (2000~2021), and Korea Environmental Industry and Technology Institute (2009~2021). The reports were classified by background (residents' demand, HES, and more), research design (cross-sectional study, cohort, ecological study, and panel), pollution source (abandoned metal mine (AMM), industrial complex (IC), and more), and assessment method of exposure and health effects. The survey area was converted into administrative district codes for geographical mapping. Results: There were 37, 34, 18, and 10 cases associated with AMM, IC, waste incinerators, and coal-fired power plants, respectively. Most of the studies conducted were cross-sectional studies and ecological studies. The proportion of epidemiological investigations by residents' demand showed an increase from 0.0% to 8.9% for the central government while decreasing from 16.7% to 14.3% for local governments after 2008 compared to before 2008. HESs increased at both the central and local government levels since 2014. For the evaluation method, 365 environmental hazards, 319 health outcomes, and 302 biological markers were investigated, with the most commonly investigated items being metals, cancer, and blood metals. Conclusions: HESs of residents in ECVAs in South Korea have been continuously developed both quantitatively and qualitatively. Future improvements are expected, and systematic review and classification of the HESs is warranted.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.29 no.5B
• /
• pp.473-482
• /
• 2009

This study numerically discusses wave forces acting on a vertical wall such as breakwaters or revetments, subjected to incident undular or turbulent bores. Due to the complex hydrodynamics of bore, its wave forces have been predicted, mainly through laboratory experiments. Numerical simulations in this paper were carried out by CADMAS-SURF(CDIT, 2001), which is based on Navier-Stokes momentum equations and VOF method (Hirt and Nichols, 1981) for tracking free water surface. Its original source code was also partly revised to generate bore in the numerical water channel. Numerical raw data computed by CADMAS-SURF included great strong spike phenomena that show the abrupt jumps of wave loads. To resolve this undesired noise of raw data, the band-pass filter with the frequency of 5Hz was utilized. The filtered results showed reasonable agreements with the experimental results performed by Matsutomi (1991) and Ramsden (1996). It was confirmed that CADMASSURF can be applied to the design of coastal structures against tsunami bores. In addition, the transformation process and propagation speed of bores in the same 2-d water channel were discussed by the variations of water level for time and space. The numerical results indicated that the propagation speed of bore was changed due to the nonlinear interactions between negative and reflected waves.