• Journal of Korean Society on Water Environment
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• v.26 no.3
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• pp.497-506
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• 2010

Severe muddy water problem has been the hot issue in Korea. Because of increased nonpoint source pollutions at Kangwon province, best soil erosion management system is required to reduce inflow of nonpoint source pollutions into the waterbodies. The USLE-based SATEEC system have been developed and enhanced for soil erosion and sediment yield estimation. However, the SATEEC cannot estimate soil depositions depending on topography in the watershed, while the USPED estimates soil erosion and deposition using sediment transport capacity of the surface runoff. In this study, the SATEEC and USPED were used to determine soil erosion hot spot subbasins. For this, 54 subbasins were delineated. In general, soil erosion hot spot subbasins were identified similarly with SATEEC and USPED. However, depending on erosion and deposition patterns in each subbasin. USPED estimated soil erosion hot spot subbasins didn't match those estimated with SATEEC. For some subbasins, much deposition was expected than erosion. This indicates that SATEEC estimated soil erosion values may be overestimated for these subbasins. Thus, care should be taken when understanding soil erosion status in the watershed based on USLE-based SATEEC results. In addition, the USPED results could be used to identify the site-specific soil erosion best management practices. If the USPED and USLE-based SATEEC are combined, it would help determining soil erosion hot spot subwatersheds in economic and environmental perspectives.

• Journal of the Korean Wood Science and Technology
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• v.41 no.3
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• pp.187-200
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• 2013

Current research trends of non-copper wood preservatives for enhancing durability was reviewed; as a follow-up of the review in 2012 on copper-based wood preservatives. Main environmental friendly non-copper wood preservatives studied by many scientists were boron-based compounds, synthetic compounds from natural products, and pyrethroids family of chemicals, etc. The critical issue regarding treated woods with boron-based compounds used outdoors was the leaching of boron. Many studies mainly focused on boron fixation improvement using variety of polymers. Moreover, the studies showed notable increases in attempts to use natural products used commonly in the medical fields as wood preservatives as well as outdoor use of chemical modified such as acetylated wood developed in purpose of stabilizing dimension.

• Water for future
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• v.26 no.1
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• pp.63-69
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• 1993

Remediation technology becomes an issue in environmental engineering. The vibro-recovery technique is one of popular means to remove pollutants from contaminated soils and groundwater. Using Ultrasonic excitation in soil-fluid medium, it was found that removal efficiency in a mechanical effects was significant. In this paper, therefore, laboratory experiments were conducted on clayey sand soil columns using a probe-type ultrasonic processor. Ultrasonic treatment with simultaneous pumping enhances dislodgement of clay particles, and ultrasonic excitation reduced the proportions of finer particles and thus result in increased hydraulic conductivity significantly. Also, the results provided the changes in grain size distribution curve of the soil due to ultrasonic excitation. The results indicated that the maximum size of particles mobilized by Ultrasonic is about 0.004mm and particles in the size range from 0.04mm to 1.0mm were subjected to fracturing. The economic feasibility of Ultrasonic implementation is considered in power requirement of the generator and maintenance of the horn. At a specified amplitude of vibrations, the power requirement of the generator depends on overburden pressure of the horn, temperature and viscosity of fluid in the soil medium. For comparisons, the requirement of a one inch and two inch diameter horn sonicators are compared with the power required for pumping water from different depths.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.6
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• pp.873-880
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• 2011

As environmental pollution, global warming, and exhaustion of fossil fuel become global issue recently, there has been strong research motivation to develop green energy technology. Along the same line of motivation, some research efforts have been put into the development of environment-friendly bicycle equipped with various smart energy technologies to increase the usability of the bicycle as short-distance transportation. Among the technologies related with new generation bicycle, PAS (power assist system) is one of the most important systems that are essential in efficiently integrating human power and the electrical power supplied by electric motor driven by battery. In this paper, a novel torque sensor technology which is core component for PAS is proposed. Unlike existing technologies, strain gauges are attached to rear shaft directly under the hub bearings, which eliminates the requirement of slip-ring, Furthermore, the sensor is able to not only measure the torque transmitted to driving axle by human but also estimate the position of the gear to which the chain is currently engaged.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.5
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• pp.115-124
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• 2001

The purpose of this study is to examine the rightness of establishing the Essential Act of Landscape Architecture in Korea and to present the legal phase, the legislative system and the construction of a contents at the expected enactment of it. It is necessary to point out the problems of the various fields of landscape architecture and to propose the solutions of them. The contents of the study are as follows, 1 . The number of the regulations related to landscape architecture is a good reason for which the field of landscape architecture is worth being included to the positive law. 2. The problems by items(ordinance, engineer, contract, planning, design and supervision, construction, maintenance, plant and planting, material, aesthetics and sight, environmental conservation and ecology, right and penal regulations) to the domestic related regulations being at issue and the remedies for it shall be considered at the enactment of the Essential Act of Landscape Architecture. 3. The number of the domestic regulations being related to landscape architecture which have a term of\` the Essential Act∼\`is 5. 4. The Essential Act of Landscape Architecture is the separate Essential Act welch defines the scope of landscape architecture as construction works and controls the business essentially. 5. The meaning and character of the Essential Act of Landscape Architecture was examined and the reasons for that essential act were recognized in point of the legal, landscape architectural and educational systems. 6. The creation of new official landscape architectural organization is a reason to justify the enactment of the Essential Act of Landscape Architecture. 7. The legal phase, the legislative system and the construction of a contents of the Essential Act of Landscape Architecture ware presented and this act shall conform to such as the legal system of the Architectural Act, the Essential Act of the Construction Industry and so on. The result of this study will be the basic materials for the creation of the Essential Act of Landscape Architecture.

• Journal of Navigation and Port Research
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• v.28 no.3
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• pp.259-268
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• 2004

For the last years, it has become hot issue such as disposal of the treated wastewater, which caused by increment of a population and industrial development at the coastal areas. The ocean outfall system discharges primary or secondary treated effluent into coastline or at the deep water, or between these two. The effluent, which has a density similar to that of fresh water, rises to the see, surface forming plume or jet, together with entraining the surrounding salt water and becomes very dilute. This paper deals ocean outfall design which effects to decision-making about marine environment management and wastewater treatment. In order to make predictions of dilution of discharged water and the trajectory of a plume, CORMIX has been used considering several elements including a seasonal and tidal changes. These solutions are strung together to provide basic data and general drawings for effective management of outfall.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.5
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• pp.147-153
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• 2018

Beacon enables one to measure distance indoors based on low-power Bluetooth low energy (BLE) technology, while GPS (Global Positioning System) only can be used outdoors. In measuring indoor distance using Beacon, RSSI (Received Signal Strength Indication) is considered as the one of the key factors, however, it is influenced by various environmental factors so that it causes the huge gap between the estimated distance and the real. In order to handle this issue, we propose the adaptive ANN (Artificial Neural Network) based approach to measuring the exact distance using Beacon. First, we has carried out the preprocessing of the RSSI signals by applying the extended Kalman filter and the signal stabilization filter into decreasing the noise. Then, we suggest the multi-layered ANNs, each of which layer is learned by specific training data sets. The results showed an average error of 0.67m, a precision of 0.78.

• Journal of Korean Home Economics Education Association
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• v.23 no.2
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• pp.131-148
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• 2011

The purpose of this study was to analyze the contents of housing area in Technology Home Economics textbooks of the 2007 revised curriculum which was published in 2011. The structure and the contents of housing area which are consisted of housing/living environment and use of housing space were analyzed. This study aims to examine the changes in the newly revised textbooks as well as suggesting advice for the more improved revised one in the future. For this purpose, this study employed 11 different textbooks and the results were the followings: each textbook had different quantity of pages dedicated to housing area but commonly had the wide range of terminology, plentiful amount of tables/diagrams, reading and activity materials sufficient to have students to carry out in practice. Also, the newly added contents of local area and eco-friendly life are analyzed to be well reflecting the 2007 revised curriculum. In future textbook development, it will be important that the issue of low birth rate, population ageing and green-life to be included as well as emphasizing the content of the network within the local area in order to actively prepare for the environmental issues.

• Journal of the Korea Institute of Building Construction
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• v.14 no.6
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• pp.523-529
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• 2014

Large amounts of waste shells have been produced each year from shellfish raising industries located in Korean costal areas. Due to the limited space for the waste shell disposal, the related environmental problem has been a serious issue. It is believed that using the waste shells as a source of aggregate for mortar, concrete or bricks can be a good solution. In this research, possibility of utilizing waste shells as an aggregate of mortar is investigated. Waste shells of manila clam, cockle, clam, sea mussel, and oyster were properly crushed, sieved, and sorted to meet the requirements of the grading of standard fine aggregate. After that, the waste shells were used as partial and total replacement of the fine aggregate, and their absorption and 28-day compressive strengths of mortar were measured. In general, replacement of waste shells increased the absorption and decreased the strength. However, one specimen with cockle increased compressive strength as replacement ratio increased. Mortar with cockle of 50% and 100% replacement showed higher compressive strength than that of control mortar. This increase of compressive strength was found to be affected by the strong interfacial bonding properties of the cockle and a cement matrix.

• Journal of the Korea Convergence Society
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• v.11 no.7
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• pp.79-87
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• 2020

The environmental problems caused by food waste have been a steady social issue, and the severity of the problem emerged as the 2013 London Convention banned the marine emissions of waste water. The government implemented measures related to food waste, but prior studies showed that it lacked continuity and lacked strategies for each area of occurrence, and emphasized that citizens' participation is important to implement effective reduction policies. Therefore, this study proposed a food waste disposal machine through user experience analysis as a way to induce civic participation. To this end, the design development direction was outlined in this study after the pre-research and user survey stages through FGI and user journey maps. Based on this, the proposed treatment machine facilitates the frequent discharge of waste and simplifies the process of food waste in the home. In addition, the moment of direct contact between the user and waste is only the point at which the waste is released to the handler, thereby minimizing the negative experience the user has experienced.