• Journal of Animal Science and Technology
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• v.45 no.4
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• pp.569-576
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• 2003

An experiment was conducted to investigate the effect of microbial phytase (Natuphos$^{\circledR}$) supplementation, individually and in combination with carbohydrase enzyme complex (composed of enzymes targeted to SBM dietary components such as $\alpha$-galactosides and galactomannans; ENDO-POWER$^{\circledR}$) to corn-soy basis diet with low nutrient levels on growth performance and nutrient digestibility of growing pigs. A total of 48 crossbred weaned pigs (Landrace${\times}$Yorkshire${\times}$Duroc), 29.1$\pm$0.14 kg of initial body weight, were randomly allotted to four dietary treatments, based on weight and age, according to a Randomized Complete Block Design. There were three pens per treatment and 4 pigs per pen. The dietary treatments were 1) CON (control diet with 3,380 kcal/kg of metabolizable energy, 18.96% of crude protein, 1.10% of lysine, 0.75% of calcium and 0.35% of available phosphorus), 2) LP+NTPS (CON diet with 0.15% unit lower available P levels+0.1% phytase (500 FTU/kg; Natuphos$^{\circledR}$)), 3) LEL+ENP (CON diet with 3.0% unit lower ME and lysine levels + 0.1% carbohydrase enzyme complex (ENDO-POWER$^{\circledR}$), and 4) LPEL+ENZ (CON diet with 0.15% unit lower available P levels and 3.0% unit lower ME and lysine levels+0.1% ENDO-POWER$^{\circledR}$ and 0.1% Natuphos$^{\circledR}$ (500 FTU/kg). There was no significant difference (p〉0.05) in average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR) among dietary treatments during the whole experimental period (0 to 4 weeks). Apparent digestibility of gross energy was greater in LP+NTPS and LPEL+ENZ groups than in the LEL+ENP (p<0.05). Apparent digestibility of phosphorus was greater in LP+NTPS than in LEL+ENP (p<0.05). Dry matter excretion was lowest in LPEL+ENZ and phosphorus excretion was lowest in LP+NTPS (p<0.05). Overall, pigs fed on LPEL+ENZ group tended to have better nutrient digestibility (dry matter, gross energy, crude protein and phosphorus) than pigs fed on control group. All dietary enzyme treatment groups showed lower feed cost/body weight gain of pigs than control group. In conclusion, the results from the present study suggest that the simultaneous inclusion of phytase and carbohydrase enzyme complex to diets is advantageous with respect to reducing nutrient excretion of growing pigs and may contribute to increased economic return when added to corn-soy based growing pig diets.

• Korean Journal of Environmental Biology
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• v.36 no.1
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• pp.33-42
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• 2018

The tropical peatlands have been deforested and converted to agricultural and plantation areas in Indonesia. To manage water levels and increase the overall productivity of crops, canals have been constructed in tropical peatlands. The canals destructed the structure of the tropical peatlands, and increased the subsidence and fire hazard risks in the region. The Indonesian government enacted regulations and a moratorium on tropical peatlands, in order to reduce degradation. A practical method under the regulations of rewetting tropical peatlands was to permit a canal blocking. In this study, four canal blocking projects were investigated regarding their planning, construction priority, design, building material, construction, monitoring, time and costs associated with the canal blockings. In the protected areas, regulations restricted the development of the tropical peatlands areas that were noted as deeper than 3 m, and the administration stopped issuing new concessions for future work projects for this noted criteria of land use. A noted purpose of canal blockings in these areas was to effectuate the restoration of the lands in the region. The main considerations of the restoration efforts were to maintain a durability of the blockings, and to encourage the participation of the area stakeholders. In the case of a concession area, regulations were set into place to restrict clear-cutting and shifting cultivation, and to maintain groundwater level in the tropical peatland. The most significant priorities identified in the canal blocking project were the efficiency and cost-effectiveness of the project. Nevertheless, the drainage of tropical peatlands has been continued. On the basis of a literature review on regulations and rewetting methods in tropical peatlands of Indonesia, we discussed the improvements of the regulations, and adequate canal blockings to serve the function to rewet the tropical peatlands in Indonesia. Our results would help establishing an adequate direction and recommended guideline on viable rewetting methods for the restoration of drained tropical peatlands in Southeast Asia.

• Economic and Environmental Geology
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• v.37 no.1
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• pp.121-131
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• 2004

Removal efficiencies of soil washing and soil improvement processes to remediate farmland soils and stream deposits around Goro abandoned mine were investigated with batch and column experiments. For As-contaminated farm-land soils around Goro mine, batch tests to quantify As extraction rate from contaminated soils and lime treated contaminated soils were performed. The contaminated soil mixed with lime decreased As extraction rate less than one fourth, suggesting that the soil improvement method mixed with lime dramatically decrease As extraction rate. A storage dam will be constructed in the lower part of the main stream connected to Goro abandoned mine and the amount of As extracted from the bottom soils of reservoir could be the main source to contaminate water of reservoir. The decrease of As extraction amount from the bottom in reservoir, caused by the application of the soil improvement method was investigated from the physically simulated column experiment and results showed that As extraction rate decreased to one forty when 1％ lime mixed soil improvement was applied to contaminated soils. For contaminated stream deposits connected Goro mine, the removal efficiency of the soil washing method was investigated with batch experiments. Hydrochloric acid, citric acid, acetic acid and distilled water were used as soil washing solution and 0.01, 0.05, 0.1, 0.5, 1.0 N of washing solution were applied to extract As. When washing with 0.05 N of hydrochloric acid or citric acid, more than 99.9% of As was removed from stream deposits, suggesting that As contaminated stream deposits around Goro mine be successfully remediated with the soil washing process. Total volumes of contaminated soils and deposits needed for remediation were calculated based on three different reme-diation target concentrations and the operation cost of soil washing for calculated soil volumes was estimated. Results from this research could be directly used to make a comprehensive countermeasure to remediate contaminated area around Goro mine and also many contaminated areas similar to this research area.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.3
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• pp.176-188
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• 2018

Modern urban problems are increasingly becoming a market mix that can not be solved by the power of a single department and the necessity of establishing a cooperation system based on data communication between departments is increasing. Therefore, this study analyzed Busan metropolitan city's IT projects from 2014 to 2018 in order to understand the utilization and sharing status of departmental data from the viewpoint that cooperation between departments can start from the sharing of data with high common utilization. In addition, based on the results of the FGI(Focus Group Interview) conducted for the officials of the department responsible for the informatization project, we verified the results of data status analysis. At the same time, we figured out the necessity of data link between departments through SNA(Social Network Analysis) and presented data that should be shared first in the future. As a result, most of the information systems currently use limited data only within the department that produced the data. Most of the linked data was concentrated in the information department. Therefore, this study suggested the following solutions. First, in order to prevent overlapping investments caused by the operation of individual departments and share information, it is necessary to build a small platform to tie the departments, which have high connectivity with each other, into small blocks. Second, a local level process is needed to develop data standards as an extension of national standards in order to expand the information to be used in various fields. Third, as another solution, we proposed a system that can integrate various types of information based on address and location information through application of cloud-based GIS platform. The results of this study are expected to contribute to build a cooperation system between departments through expansion of information sharing with cost reduction.

• Journal of Korea Water Resources Association
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• v.48 no.12
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• pp.1065-1075
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• 2015

In the estuary where the structure such as river-mouth weir has been installed, the flow is developed very complicatedly due to river water from upstream, tide of the sea and floodgate operation. Especially, if basin outlets more than one exists in one estuary, the boundary conditions will be significantly more complex form. Saemangeum(SMG) project area in Korea is the most typical example. There are Mankyung river and Dongjin river in upstream. The water of them inflows into SMG project area. In the downstream, river flow was drained from inland to sea over the SMG sea dike through the sluice. The connecting channel was located between Mankyung and Dongjin basins. It functions not only as transportation by ship in ordinary period but also as flood sharing by sending flood flow to each other in flood period. Therefore, in order to secure the safety against flood, it is very important to understand the flood sharing capacity for connecting channel. In this study, the flood control effect was analyzed using numerical simulation. Delft3D was used to numerical simulation and simulated period was set up with neap tide, in which the maximum flood stage occurred due to poor drainage. Actually, three connecting channels were designed in land use plan of the SMG Master Plan, but they were simplified to a single channel for conciseness of analysis in this study. According to the results of numerical analysis, the water level difference between two basins was increased and the maximum flood stage at dike sluice was also upraised depending on decrease of conveyance. And the velocity induced by same water level difference was decreased when the conveyance became smaller. In certain conveyance above, there was almost no flood control effect. Therefore, if the results of this study are considered for design of connecting channel, it will be expected to draw the optimal conveyance for minimizing dredging construction cost while maximizing the flood control effect.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.9
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• pp.637-648
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• 2009

As the cost of disks decreases, PCs are soon expected to be equipped with a disk of 1TB or more. Assuming that a single person generates 1GB of data per month, 1TB is enough to store data for the entire lifetime of a person. This has lead to the growth of researches on lifelog management, which manages what people see and listen to in everyday life. Although many different lifelog management systems have been proposed, including those based on the relational data model, based on ontology, and based on file systems, they have all advantages and disadvantages: Those based on the relational data model provide good query processing performance but they do not support complex queries properly; Those based on ontology handle more complex queries but their performances are not satisfactory: Those based on file systems support only keyword queries. Moreover, these systems are lack of support for lifelog group management and do not provide a convenient user interface for modifying and adding tags (metadata) to lifelogs for effective lifelog search. To address these problems, we propose a lifelog management system based on the relational data model. The proposed system models lifelogs by using the relational data model and transforms queries on lifelogs into SQL statements, which results in good query processing performance. It also supports a simplified relationship query that finds a lifelog based on other lifelogs directly related to it, to overcome the disadvantage of not supporting complex queries properly. In addition, the proposed system supports for the management of lifelog groups by providing ways to create, edit, search, play, and share them. Finally, it is equipped with a tagging tool that helps the user to modify and add tags conveniently through the ion of various tags. This paper describes the design and implementation of the proposed system and its various applications.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.6
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• pp.697-703
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• 2023

As a part of the global industrial efforts to reduce environmental pollution owing to air pollution, regulations have been established by the International Maritime Organization (IMO). The IMO has implemented various regulations such as EEXI, EEDI, and CII to reduce air pollution emissions from ships. They are also promoting measures to decrease the power consumption in ships, aiming to conserve energy. Most of the power used in ships is consumed by electric motors. Among the motors installed on ships, the engine room blower that takes up a significant load, operates at a constant irrespective of demand. Therefore, energy savings can be expected through frequency control. In this study, we demonstrated the efficacy of energy savings by controlling the frequency of the electric motor of the generator blower that supplies combustion air to the generator's turbocharger. The system was modeled based on the output data of the turboharger outlet temperature in response to the blower frequency inpu. A PI control system was established to control the frequency with the target being the turbocharger outlet temperature. By maintaining the turbocharger design standard outlet temperature and controlling the blower frequency, we achieved an annual energy saving of 15,552kW in power consumption. The effectiveness of energy savings through frequency control of blower fans was verified during the summer (April to September) and winter (March to October) periods. Based on this, we achieved annual fuel cost savings of 6,091 thousand won and reduction of 8.5 tons of carbon dioxide, 2.4 kg of SOx, and 7.8 kg of NOx air pollutants on the training ship.

• Journal of the Korean Geographical Society
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• v.42 no.4
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• pp.469-487
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• 2007

Grain-Size Trend Analysis is the methodology to identify net sediment transport pathways, based on the assumption that the movement of sediment from the source to deposit leaves the identifiable spatial pattern of mean, sorting, and skewness of grain size. It can easily be implemented with low cost, so it has great potentials to contribute to geomorphological research, whereas it can also be used inadequately without recognition of its limitations. This research aims to compare three established methods of grain-size trend analysis to search for the adequate way of application, and also suggest the research tasks needed in improving this methodology 1D pathway method can corporate the field experience into analyzing the pathway, provide the useful information of depositional environments through X-distribution, and identify the long-term trend effectively. However, it has disadvantage of the dependence on subjective interpretation, and a relatively coarse temporal scale. Gao-Collins's 2D transport vector method has the objective procedure, has the capability to visualize the transport pattern in 2D format, and to identify the pattern at a finer temporal scale, whereas characteristic distance and semiquantitative filtering are controversial. Le Roux's alternative 2D transport vector method has two improvement of Gao-Collins's in that it expands the empirical rules, considers the gradient of each parameters as well as the order, and has the ability to identify the pattern at a finer temporal scale, while the basic concepts are arbitrary and complicated. The application of grain sire trend analysis requires the selection of adequate method and the design of proper sampling scheme, based on the field knowledge of researcher, the temporal scale of sediment transport pattern targeted, and information needed. Besides, the relationship between the depth of sample and representative temporal scale should be systematically investigated in improving this methodology.

• Journal of Bio-Environment Control
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• v.24 no.4
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• pp.308-316
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• 2015

This study was conducted to investigate the situation of ICT apply to plastic greenhouse, and the results be apply to design of new one. A CFD analysis were conducted to monitering the ventilation and energy saving of the single span greenhouse newly designed. The causes of delay to apply ICT to plastic greenhouse are the high cost for installation(24%), insufficiency of after services(19%), often disorder(16%), unskillful management of soft ware(15%), insufficient ICT efficiency(13%) and unsatisfying of income increase(12%). The parts of problem occurred in ICT plastic greenhouse are the structure, actuator, environmental control system and sensor(approximate 14%, respectively), remote control technique(13%), plant management technique(12%), energy saving technique(10%) and utilization of software(8%). In the condition of lateral window closed, the average wind speed changed to slow, but it was faster in the condition of leeward side window opened than in the condition of lee and winward side window opened. The air movement in the condition of lateral window closed occur by air moving fan not by out air. It is not affect the room temperature but effective the uniformity of room temperature. The average temperature of low height greenhouse was uniform than high height one. The average temperature in condition of 3rd curtain opened become same with outside temperature after 2 hours, but take more 5 hours in condition of 3rd curtain closed.

• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.419-428
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• 2021

In order to develope a mobile-based greenhouse energy calculation program, firstly, the overall thermal transmittance of 10 types of major covers and 16 types of insulation materials were measured. In addition, to estimate the overall thermal transmittance when the cover and insulation materials were installed in double or triple layers, 24 combinations of double installations and 59 combinations of triple installations were measured using the hotbox. Also, the overall thermal transmittance value for a single material and the thermal resistance value were used to calculate the overall thermal transmittance value at the time of multi-layer installation of covering and insulating materials, and the linear regression equation was derived to correct the error with the measured values. As a result of developing the model for estimating thermal transmittance when installing multiple layers of coverings and insulating materials based on the value of overall thermal transmittance of a single-material, the model evaluation index was 0.90 (good when it is 0.5 or more), indicating that the estimated value was very close to the actual value. In addition, as a result of the on-site test, it was evaluated that the estimated heat saving rate was smaller than the actual value with a relative error of 2%. Based on these results, a mobile-based greenhouse energy calculation program was developed that was implemented as an HTML5 standard web-based mobile web application and was designed to work with various mobile device and PC browsers with N-Screen support. It had functions to provides the overall thermal transmittance(heating load coefficient) for each combination of greenhouse coverings and thermal insulation materials and to evaluate the energy consumption during a specific period of the target greenhouse. It was estimated that an energy-saving greenhouse design would be possible with the optimal selection of coverings and insulation materials according to the region and shape of the greenhouse.