• Journal of the Korean earth science society
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• v.27 no.6
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• pp.677-686
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• 2006

Surface evapotranspiration is one of the most important factors to determine the surface energy budget, and its estimation is strongly related with the accuracy of weather forecasting. Surface evapotranspiration over Daegu Metropolitan was estimated using high resolution LANDSAT TM data. The estimation of surface evapotranspiration is based on the relationship between surface radiative temperature and vegetation index provided by a TM sensor. The distribution of NDVI (Normalized Difference of Vegetation Index) corresponds well with that of land-used in Deagu Metropolitan. The temperature of several part of downtown in Deagu metropolitan is lower in comparison with the averaged radiative temperature. This is caused by the high evapotranspiration from dense vegetation like DooRyu Park in Deagu Metropolitan. But, weak evapotranspiration availability is distinguished over the central part of downtown and the difference of evapotranspiration availability on industrial complexes and residential area is also clear.

• Journal of Digital Convergence
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• v.12 no.2
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• pp.69-78
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• 2014

This study aims to analyze the current state and causes of digital media literacy divide according to its sub-factors. The effects of the generation and the economic status, among other variables, have been explored using empirical data from a large-scale survey of 2,171 media users including children, adolescents, adults and the elderly. The results showed that the effects of generation and economic status varied according to 8 components of digital media literacy. The economic status of media users has also been found to influence the divide among adults group and through the interaction effect with the generation factor. Policy suggestions for the solution of digital media literacy divide were discussed in conclusion.

• Journal of Adhesion and Interface
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• v.17 no.3
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• pp.104-109
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• 2016

Compare AC corona and DC corona treatment effects, polyester fabrics were AC corona treated with different current intensity (5, 10, 15 A) and feeding speed (5, 10, 15 m/min) as the same DC corona treatment conditions of the preceding research. We confirmed the surface change of polyester fabrics using scanning electron microscopy (SEM) and X-ray photoelectron spectrometer (XPS), and the change of physical properties through measuring the dry and wet bonding strength. The surface changes of polyester fabrics by treating in air atmosphere with AC corona discharge are shown similar tendency with DC corona discharge. Generally dry bonding strength were increased with increasing current intensity and feeding speed, but wet bonding strength were increased with increasing current intensity and decreasing feeding speed in both AC and DC corona treatment. When the current is 20 A, carbonization occurs in DC corona discharge but carbonization does not occur in DC corona discharge.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.12C
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• pp.983-990
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• 2008

In communication systems, initial acquisition is required for the reliable transmission performance, and the analysis of the acquisition performance over various communication environments including different signal-to-noise ratios plays an important role in communication system design. Usage of differential correlation methods in initial synchronization procedure is desired when frequency offsets exist, and additional performance improvement can be achieved through proper modifications of conventional correlation schemes. In this paper, we derive the error probability of the initial acquisition and express it in terms of the Marcum Q-function, via statistical modeling of the differential correlator output. The result is generalized to the error probabilities of the extended differential correlation methods using the complex- and magnitude-sum of the correlator outputs. The derived probabilities can be applied for the acquisition performance verification of various communication systems including the DVB-S2 standard.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.711-717
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• 2017

Startability and harmful emissions are the main issues in diesel engine development under cold conditions. The characteristics of combustion with multiple injection were investigated under cold start conditions. For quantitative analysis, the in-chamber pressure profile was measured and combustion visualization using direct imaging was accomplished. With multiple injection, the peak in-chamber pressure and heat release rate were increased compared to single injection. In addition, the period of flame luminosity detection was shortened using multiple injection. Combustion by main injection was improved with an increase in heat released by pilot combustion when the pilot injection quantity was increased. Finally, an increase in injection pressure also showed the possibility of combustion improvement. On the other hand, an increase of in the pilot injection quantity and injection pressure can cause an increase in harmful emissions, such as HC and CO due to wall wetting. Therefore, more sensitive calibration will be needed when applying a multiple injection strategy under cold start conditions.

• Journal of the Korea Convergence Society
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• v.12 no.1
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• pp.77-87
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• 2021

Environment is an important factor in city life. Environmental elements are a subject that must be discussed in the smart city plan, but there is still a lack of information and data sharing in the urban environment, so improvements are needed. As part of the intelligent of Nanjing, this research has made in-depth investigation into the construction and service demand of environmental information, and has carried out the research on the design and construction of intelligent information platform that conforms to Nanjing intelligent city planning, improves environmental quality and provides environmental information service. The visualization of information is also studied. The result is an important module in the construction of intelligent city in Nanjing.

• Journal of Korean Society of Archives and Records Management
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• v.21 no.4
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• pp.163-181
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• 2021

Photographic records capturing the changes of a city are vital parts of local history archives. They were, however, not collected properly for the local history archives even by local governments. Therefore, as a solution for this problem, seven major cities (Seoul, Incheon, Gwangju, Ulsan, Daejeon, Busan, and Daegu) initiated the urban landscape documentation project for archiving the photographic records of each city. This study investigated the current status of the urban landscape documentation project and found that Daegu metropolitan city's project only holds some of the contest photos and a few old photos from the local government. A proper donating process is urgently needed to preserve valuable photographic records of Daegu, and this study aims solutions for the Daegu metropolitan city's urban landscape documentation project to improve the acquisition methods of photographic records. This study suggests the process for photographic records donation from citizens and a metadata set for donated photographs.

• Journal of Digital Convergence
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• v.20 no.5
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• pp.375-381
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• 2022

The DEA-BCC model. And the Malmquist index have been used, from static and dynamic perspectives, to measure the eco-efficiency of 30 cities and provinces in China from 2011 to 2020. The results shows that: the average static eco-efficiency of 30 cities and provinces in China is 0.643. Differences exists all over China. While Shanghai and Beijing are ecologically efficient, other 28 cities and provinces are faced with different extents of inefficiency. There are also differences among regions, which generally show the spatial distribution pattern with high efficiency in the eastern regions while low in the western regions. The Malmquist index of eco-efficiency in total 30 cities and provinces shows a healthy growth trend, and the technological progress. Acts as its main driving force. Therefore, eastern regions should enhance the. radiation capacity, strengthen the synergy among regions, give full play to. The advantages of each regions. It is sensible to improve the eco-efficiency by means of optimizing the industrial structure, enhancing the technological level and improving eco-efficiency of China and realizing green development.

• Journal of the Korean Society for Library and Information Science
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• v.56 no.1
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• pp.365-386
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• 2022

The purpose of this study is to understand the changes in human information behavior brought about by the pandemic situation. This study also examines the social context of data literacy as lifelong education. In addition, it was attempted to understand the changed environment and propose library services in the post-pandemic era based on predicted trends. In order to do this, two phenomena that are currently striking our society, datafication and the pandemic, were reviewed in general, and studies related to library information services in response to the pandemic were examined. Based on this, the social meaning of data literacy in the pandemic era was reconfirmed and the environmental changes faced by libraries were examined based on 20 trends suggested by IFLA. Through this process, the study was concluded by suggesting the implementation of data literacy and the direction of library services.

• Korean Journal of Agricultural Science
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• v.35 no.1
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• pp.85-100
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• 2008

The United States Department of Agriculture (USDA) funded collaborative project on The Economic Feasibility Analysis of Crop Cultivation Practice Project in Pirganj and Kurigram Districts in Bangladesh will started during 2008-2012, for 4 years with total project cost of US$ 571,270. The project will be implemented in 6 villages; has 1,097 hectares areas which is divided into 948 hectares of agricultural land, 52 hectares of forest land and 345 hectares of other land, covered 1,059 households equal to 5,305 persons in Pirganj and Kurigram districts The project has proposed to be implemented in joint collaboration by Bangladesh Agricultural Research Council (BARC), Bangladesh Agricultural Research Institute (BARI) and Rangpur Dinajpur Rural Service (RDRS) Bangladesh with full participation of the farmers' groups of respective project site. The specific objectives of the project are: (1) to estimate the productivity of paddy, wheat, maize, tobacco and sugarcane (2) to determine the cost of production and returns to the above mentioned crops (3) to study the interrelationship between inputs and output of the above mentioned crops and (4) to examine the resource utilization patterns at farm level. In this project analysis, the net incremental profit is US$33,028. The expected incremental project benefit and incremented production cost are estimated as US$ 219,959 and US$ 186,931 respectively. The financial decision making criteria would be followed in this crop cultivation practice project. After the project implementation, the expected project benefits are assumed to be continued for 15 years. The benefit cost ratio (B/C) of the project is estimated at 1.077 (table 11) when using discount rate of 10% as an opportunity cost of capital in Bangladesh. FIRR of project is estimated at 26.15% which is bigger than the opportunity cost by more than double. So this project is financially feasible and acceptable. Therefore, this project should be extended to other areas to increase the farm income and economic growth of marginal poor farmers in Bangladesh.