• International Journal of Highway Engineering
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• v.8 no.2 s.28
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• pp.55-62
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• 2006

Transverse cracks in continuously reinforced concrete pavement (CRCP) occur at early ages due to temperature and moisture variations. The width and spacing of transverse cracks have a significant effect on pavement performance such as load transfer efficiency and punchout development. Also, crack widths in CRCP depend on 'zero-stress temperature,' which is defined as a temperature where initial concrete stresses become zero, as well as drying shrinkage of concrete. For good long-term performance of CRCP, transverse cracks need to be kept tight. To keep the crack widths tight throughout the pavement life, zero-stress temperature must be as low as practically possible. Thus, temperature control at early ages is a key component In ensuring good CRCP performance. In this study, concrete temperatures were predicted using PavePro, a concrete temperature prediction program, for a CRCP construction project, and those values were compared with actual measured temperatures obtained from field testing. The cracks were also surveyed for 12 days after concrete placement. Findings from this study can be summarized as follows. First, the actual maximum temperatures are greater than the predicted maximum temperature in the ranges of 0.2 to 4.5$^{\circ}C$. For accurate temperature predictions, hydration properties of cementitious materials such as activation energy and adiabatic constants, should be evaluated and accurate values be obtained for use as input values. Second, within 24 hours of concrete placement, temperatures of concrete placed in the morning are higher than those placed in the afternoon, and the maximum concrete temperature occurred in the concrete placed at noon. Finally, from the 12 days of condition survey, it was noted that the rate of crack occurrence in the morning placed section was 25 percent greater than that in the afternoon placed section. Based on these findings, it is concluded that maximum concrete temperature has a significant effect on crack development, and boner concrete temperature control is needed to ensure adequate CRCP performance.

• Information Systems Review
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• v.14 no.1
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• pp.85-103
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• 2012

ISMP is a method of writing clearly the user requirements in the RFP(Request for Proposal) of the IS development projects. Unlike the conventional methods of RFP preparation that describe the user requirements of target systems in a rather superficial manner, ISMP systematically identifies the businesses needs and the status of information technology, analyzes in detail the user requirements, and defines in detail the specific functions of the target systems. By increasing the clarity of RFP, the scale and complexity of related businesses can be calculated accurately, many responding companies can prepare proposals clearly, and the level of fairness during the evaluation of many proposals can be improved, as well. Above all though, the problems that are posed as chronic challenges in this field, i.e., the misunderstanding and conflicts between the users and developers, excessive burden on developers, etc. can be resolved. This study is a case study that analyzes the execution process, execution accomplishment, problems, and the success factors of two pilot projects that introduced ISMP for the first time. ISMP performance procedures of actual site were verified, and how the user needs in the request for quote are described was examined. The satisfaction levels of ISMP RFP for quote were found to be high as compared to the conventional RFP. Although occurred were some problems such as RFP preparation difficulties, increased workload, etc. due to the lack of understanding and execution experience of ISMP, in overall, also occurred were some positive effects such as the establishment of the scope of target systems, improved information sharing and cooperation between the users and the developers, seamless communication between issuing customer corporations and IT service companies, reduction of changes in user requirements, etc. As a result of conducting action research type in-depth interviews on the persons in charge of actual work, factors were derived as ISMP success factors: prior consensus on the need for ISMP, the acquisition of execution resources resulting from the support of CEO and CIO, and the selection of specification level of the user requirements. The results of this study will provide useful site information to the corporations that are considering adopting ISMP and IT service firms, and present meaningful suggestions on the future study directions to researchers in the field of IT service competitive advantages.

• Journal of Korea Port Economic Association
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• v.33 no.3
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• pp.35-52
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• 2017

Interest and demand in heavy cargo logistics is increasing and becoming more diverse as economic scales have expanded and manufacturing activity has increased. Although cargo moves via maritime and/or land transportation, there is currently insufficient research on the actual condition of heavy cargo logistics. The purpose of this study is to carry out an in-depth analysis of heavy cargo laws, systems, logistics patterns, and current transportation status. By proposing measures to solve existing problems, this study aims to make an important and ongoing contribution to the scarcely studied field of heavy cargo logistics. The result of regression analysis on the main seven factors show that transportation frequency and law/system structure have a positive effect on working conditions. Furthermore, the result of correlation analysis on the main seven factors show that the cargo weight variable is highly positively correlated with cargo size. Also, the working conditions variable is highly positively correlated with the law/system structure. Detailed proposal measures to solve existing problems are summarized as follows. First, it is necessary to establish a clear concept of heavy cargo as numerous existing definitions differ. Second, laws and provisions relating to maritime and land transportation of heavy cargo need to be established and consolidated as current applicable legislation is insufficient. Third, the classification system for heavy cargo transportation needs improvement. Fourth, it is necessary to improve transportation performance statistics and the aggregate criteria system. Finally, the management system of heavy cargo also needs improvement.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.3761-3771
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• 2010

This study, based on social capital theory, aims to explore how social network characteristics among organization members affect the absorptive capacity which is the ability to recognize the value of new information, assimilate it, and apply it to commercial ends. This paper also empirically investigates how the absorptive capacity will have an effect on organizational innovation performances toward achieving competitive advantages in the knowledge society. According to the degree of relationship intensity, social network shows two different characteristics: strong tied network and weak tied network. As strong tied network and weak tied network have relatively different network characteristics, this study assumes that each network affects the absorptive capacity with different aspects. Furthermore, we consider the moderation effect of a social network manager's ability in the relationship between social network and absorptive capacity. We surveyed innovative project performers who are engaged in the knowledge based industries. The empirical analysis results show that both strong tied and weak tied network positively affect the absorptive capacity. Successively, the absorptive capacity also has a positive impact on innovation performances.

• International Journal of Highway Engineering
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• v.5 no.4 s.18
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• pp.1-11
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• 2003

Recently, the new pavement design method considering Korean environment and the specification for improving performance of pavement are being developed in Korea. The Jointed Concrete Pavement Program Applying Load Discretization Algorithm (called HEART-JCP) is one of the results of Korea Pavement Research Project in Korea. HEART-JCP program is developed to analyze various loading condition using the load discretization algorithm without mesh refinement. In addition, it can be modified easily into multi-purpose concrete pavement nidyses program because of the modularized structure characteristic of HEART-JCP. The program consists of basic program part and load discretization part. In basic program part, the displacement and stress are computed in the concrete slab, sub-layer, and dowel bar, which are modeled with plate/shell element, spring element and beam element. In load discretization program part, load discretization algorithm that was used for the continuum solid element is modified to analyze the model with plate and shell element. The program can analyze the distributed load, concentrated load, thermal load and body load using load discretization algorithm. From the result of verification and sensitivity study, it was known that the loading position, the magnitude of load, and the thickness of slab were the major factors of concrete pavement behavior as expected. Since the result of the model developed is similar to the results of Westergaard solution and ILLISLAB, the program can be used to estimate the behavior of jointed concrete pavement reasonably.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.10
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• pp.1101-1107
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• 2014

A heavy ion accelerator is a device that accelerates heavy ions in the radio frequency (RF) range. The electric field that flows into the RF cavity continuously accelerates heavy ions in accordance with the phase of the input electromagnetic wave. For the purpose, it is necessary to design a coupler shape that can stably transfer the RF wave into the cavity. The RF coupler in a heavy ion accelerator has a large temperature difference between the input port and output port, which radiates the RF waves. It is necessary to consider the heat deflection on the RF coupler that occurs as a result of the rapid temperature gradient from an ultra-low temperature about 0 K to a room temperature about 300 K. The purpose of this study was to improve the system performance through an analysis of the intensity of the output electric field and temperature distribution considering various shapes of the RF coupler, along with an analysis of the durability considering the heat deflection and heat loss.

• The Journal of Engineering Geology
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• v.30 no.3
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• pp.315-325
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• 2020

This study was performed to develop a model to predict landslides and determine the variable importance of landslides susceptibility factors based on the probabilistic prediction of landslides occurring on slopes along the road. Field survey data of 30,615 slopes from 2007 to 2020 in Korea were analyzed to develop a landslide prediction model. Of the total 131 variable factors, 17 topographic factors and 114 geological factors (including 89 bedrocks) were used to predict landslides. Automated machine learning (AutoML) was used to classify landslides and non-landslides. The verification results revealed that the best model, an extremely randomized tree (XRT) with excellent predictive performance, yielded 83.977% of prediction rates on test data. As a result of the analysis to determine the variable importance of the landslide susceptibility factors, it was composed of 10 topographic factors and 9 geological factors, which was presented as a percentage for each factor. This model was evaluated probabilistically and quantitatively for the likelihood of landslide occurrence by deriving the ranking of variable importance using only on-site survey data. It is considered that this model can provide a reliable basis for slope safety assessment through field surveys to decision-makers in the future.

• Korean Journal of Construction Engineering and Management
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• v.6 no.4 s.26
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• pp.101-112
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• 2005

Recently, a curtain wall construction is a exterior finishing components which is most used for shortening time in high-rise building as well as the class of key management factors in cost and schedule control. Also, it is recognized that an effective management for curtain wall process is a major subject to accomplish the project successfully. However, as the current management for curtain wall construction is focused on the construction stage, it makes problems such as errors in business performance, rework by mistakes and duplications, errors and omissions by ineffective information management and there has never been any efficient management from a view of the entire Curtain Wall Life-cycle process. Therefore, the aim of this study is to suggest a stage check point for process improvement in the curtain wall Life-cycle process through current curtain wall process analysis, and then to investigate the cause of waste factors using the Muda method from the Toyota Production System and extract the weighted effects of the waste factors using the analytical hierarchy process method. According to the result, Most of the inefficient factors happened in architectural design stage of the entire curtain wall Life-cycle process and my research identified that detail factors of them are a delay of decision making and an approval in changes, a deficit of engineering capacity and a delay of approval in architectural design drawings by owner, etc.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.3
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• pp.303-321
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• 2011

The availability and efficient use of the feed resources in Asia are the primary drivers of performance to maximise productivity from animals. Feed security is fundamental to the management, extent of use, conservation and intensification for productivity enhancement. The awesome reality is that current supplies of animal proteins are inadequate to meet human requirements in the face of rapidly depleting resources: arable land, water, fossil fuels, nitrogenous and other fertilisers, and decreased supplies of cereal grains. The contribution of the ruminant sector lags well behind that of non-ruminant pigs and poultry. It is compelling therefore to shift priority for the development of ruminants (buffaloes, cattle, goats and sheep) in key agro-ecological zones (AEZs), making intensive use of the available biomass from the forage resources, crop residues, agro-industrial by-products (AIBP) and other non-conventional feed resources (NCFR). Definitions are given of successful and failed projects on feed resource use. These were used to analyse 12 case studies, which indicated the value of strong participatory efforts with farmers, empowerment, and the benefits from animals of productivity-enhancing technologies and integrated natural resource management (NRM). However, wider replication and scaling up were inadequate in project formulation, including systems methodologies that promoted technology adoption. There was overwhelming emphasis on component technology applications that were duplicated across countries, often wasteful, the results and relevance of which were not clear. Technology delivery via the traditional model of research-extension linkage was also inadequate, and needs to be expanded to participatory research-extension-farmer linkages to accelerate diffusion of technologies, wider adoption and impacts. Other major limitations concerned with feed resource use are failure to view this issue from a farming systems perspective, strong disciplinary bias, and poor links to real farm situations. It is suggested that improved efficiency in feed resource use and increased productivity from animals in the future needs to be cognisant of nine strategies. These include priorities for feed resource use; promoting intensive use of crop residues; intensification of integrated ruminant-oil palm systems and use of oil palm by-products; priority for urgent, wider technology application, adoption and scaling up; rigorous application of systems methodologies; development of adaptation and mitigation options for the effects of climate change on feed resources; strengthening research-extension-farmer linkages; development of year round feeding systems; and striving for sustainability of integrated farming systems. These strategies together form the challenges for the future.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.864-867
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• 2003

GPS (Global Positioning System) made by the Department of Defense in U.S.A is positioning system to use satellite and initially it has been used only for the military forces but open to civilian in about 1987. This system has widely been used for not only surveying land, but also car navigation on the street and means to build up the data of the GIS. With GPS, recently our country is accelerating to make imbeded system and also the study on imbeded system is well under way. For example, Car navigation and the construction of the Seokang bridge between Willson Arch at Han river by using DGPS were evaluated as successful model to lead accurate location with the precision of the cm. The examples of the project performance with GPS has gradually been extended to the each department organization of the local and central government. for the example, It is true that BIS(Bus Information System) is widely spreading out. In addition, the study on the Distribution Maintenance System is expected to be well in progress to take advantage of GPS based on the data base of the NGIS(National Geography Institute System) of the NGI(National Geography Institute). This paper shows that we embodied not only the large imbeded system for car and finding the location in Korean Land Corporation but also the protype of the kinematics Wrist Held which is easily portable to pedestrian, climber and marathon runner.