• Journal of the Korea Concrete Institute
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• v.18 no.5 s.95
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• pp.611-620
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• 2006

In the shear failure mechanism of a beam, beam and arch actions always exist simultaneously. According to the shear span to depth ratio, the proportion between these two actions is varied and the contribution of these actions to shear capacity is changed. Moreover, the current codes provide recommendations based on experimental results of normal strength concrete, so the application range of concrete strength must be extended. Based on this mechanism and new requirement, a simplified analytical equation for shear capacity prediction of reinforced high strength concrete beams without stirrups is proposed. To reflect the change in the contribution between these actions, stress variation in the longitudinal reinforcement along the span is considered by use of the Jenq and Shah Model. Dowel action with horizontal splitting failure and shear friction between cracks are also taken into account. ize effect is included to derive a more precise equation. Regression analysis is performed to determine each variable and simplify the equation. And, the formula derived from theoretical approaches is evaluated by comparison with numerous experimental data, which are in broad range of concrete strength(especially in high strength concrete), shear span to depth ratio, geometrical size and longitudinal steel ratio. It is shown that the proposed equation is more accurate and simpler than other empirical equations, so a wide range of a/d can be considered in one equation.

• Korean Journal of Construction Engineering and Management
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• v.16 no.5
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• pp.54-64
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• 2015

The modular construction has several advantages such as high quality of product, safe work condition and short construction duration. The manufacturing planning of modular construction should consider time frame of manufacturing, transport and erection process with limited resources (e.g., modular units, transporter and workers). The manufacturing planning of multi modular construction project manages the modular construction's characteristics and diversity of projects, as a type of modular unit, modular unit quantities, and date for delivery. However, current modular manufacturing planning techniques are weak in dealing with resource interactions and each project requirement in multi modular construction project environments. Inefficient allocation of resources during multi modular construction project may cause delays and cost overruns to construction operation. In this circumstance, this research suggest a manufacturing planning model for schedule optimization of multi project of modular construction, using genetic algorithm as one of the powerful method for schedule optimization with multiple constrained resources. Comparing to the result of the existed schedule of case study, setting optimized scheduling for multi project decrease the total factory producing schedule. By using proposed optimization tool, efficient allocation of resource and saving project time is expected.

• Journal of Navigation and Port Research
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• v.35 no.10
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• pp.823-827
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• 2011

The present Common Structural Rules for double hull oil tanker is not included the residual strength, which is one of the functional requirements in design part of Goal-based new ship construction standards (GBS). The GBS will be enforced after July 1, 2016. The requirement related residual strength has the goal to build safe ship even if she has the specified damages due to marine accidents including collision and grounding. In order to assess the residual strength based on risk for structural damages according to GBS, tons of nonlinear FE analysis work taking into account various types of damage will be needed. The Smith's method, a kind of simplified method for the strength analysis is very useful for this purpose. In this paper, the residual strength assessments based on ultimate strength using Smith's method were carried out. The objected ship is VLCC with stranding damage in bottom structures. Also, the results were compared with that of nonlinear FE analysis using three cargo hold model.

• Korean Journal of Construction Engineering and Management
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• v.16 no.1
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• pp.24-34
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• 2015

As recent multilateral collaboration design system has been advanced, BIM based data exchange is a key factor for successful next generation building project. Even though many studies have been trying to set up a data compatibility system for collaboration, There are still a lot of problem in data exchange between design and engineering phase. Therefore, In this study, we analysis causes of problem for information exchange and suggest a IFC based Information exchange framework for improving BIM based design collaboration environment. In order to find out problems that hinder establishment of advanced open BIM information exchange, proper analysis about transition of process from current and to-be BIM based design collaboration process is important, at first. From analysis of main obstacles to information exchange, this research suggests solution plan using open API and IFC based BIM collaboration supporting system. The suggested open API solution named Integrity feedback system perform a role making up for weak point derived from IFC based data exchange. And main system suggestion about framework for IFC based information exchange reflect technological system support, requirement of function for collaboration including API/BCF plug-in.

• Journal of the Earthquake Engineering Society of Korea
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• v.6 no.3
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• pp.23-29
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• 2002

A wall-frame type structural system has been widely used to make full use of a limited land in large cities to satisfy the several functional requirement in one building. However, this type of hybrid structure brought some problems due to the vertical discontinuity of a structural system. The response of a wall-frame type structural system having a deep transfer girder was observed. An arch system was introduced to replace the deep transfer girder. The adequacy of an arch system was observed for the various boundary conditions of a system. The proposed system was compared to a general transfer girder system by applying both gravity load and lateral load. It was observed that an arch system fairly distributes the stress without concentrating stress at a certain location of a system differently from the current transfer girder system. The moment decrement effect of a column can also be obtained by eliminating the large mass of a transfer girder. Also it was investigated that an arch system is more economical and effective than the current transfer girder system.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.2
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• pp.140-149
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• 2008

Recently, the need for accessing information from anywhere at any time has been a driving force for a variety of mobile applications. As the number of mobile applications increases rapidly, there has been a growing demand for the use of Service Oriented Architectures(SOA) for various applications. Mobile based SOA offers a systematic way to classify and assess technical realizations of business processes. But mobile has severly restricted range of utilizing services in computing environment and more, a mobile computer is envisioned to be equipped with more powerful capabilities, including the storage of a small database, the capacity of data processing, a narrow user input and small size of display. This paper present mobile adaption method based on SOA to overcome mobile restriction. To improve mobile efficient we analyzing mobile application requirement writing service specification, optimizing design, providing extended use case specification which test use case testing and testing service test case which derived from service specification. We discuss an mobile application testing that uses a SOA as a model for deploying discovering, specifying, integrating, implementing, testing, and invoking services. Such a service use case specification and testing technique including some idea could help the mobile application to develop cost efficient and dependable mobile services.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.10
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• pp.1624-1632
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• 2020

Objective: A total of three hundred unsexed ducks were utilized to estimate net energy requirements of maintenance (NE_m) and weight gain (NE_g) for 2 to 3-week-old Cherry Valley ducks and to establish a model equation to predict NE requirements using the factorial method. Methods: To determine the apparent metabolizable energy (AME) of the diet, fifty 7-day-old ducks at approximately equal body weights (BWs) were randomly assigned into five groups that were fed at different levels (ad libitum, 85%, 75%, 65%, and 55% of ad libitum intake), and the endogenous acid-insoluble ash as indigestible marker. The two hundred and fifty 7-day-old ducks were used for a comparative slaughter experiment. At the beginning of the experiment, ten ducks were sacrificed to determine the initial body composition and energy content. The remaining ducks were randomly assigned into five groups (same as metabolic experiment). Ducks of the ad libitum group were slaughtered at 14 and 21-day-old. At the end of the experiment, two ducks were selected from each replicate and slaughtered to determine the body composition and energy content. Results: The results of the metabolizable experiment showed AME values of 13.43 to 13.77 MJ/kg for ducks at different feed intakes. The results of the comparative slaughter experiment showed the NE_m value for 2 to 3-week-old Cherry Valley ducks was 549.54 kJ/kg of BW^0.75/d, and the NE_g value was 10.41 kJ/g. The deposition efficiency values of fat (K_f) and crude protein (K_p) were 0.96 and 0.60, respectively, and the values of efficiency of energy utilization (K_g) and maintenance efficiency (K_m) were 0.75 and 0.88, respectively. Conclusion: The equation for the prediction of NE requirements for 2 to 3-week-old Cherry Valley ducks was the following: NE = 549.54 BW^0.75+10.41 ΔW, where ΔW is the weight gain (g).

• Journal of Distribution Science
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• v.11 no.4
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• pp.89-97
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• 2013

Purpose - The purpose of this study is to systematically review the background of the Korean distribution promotion policy and distribution adjustment policies along with related regulations and policies. Research design, data, and methodology - Domestic distribution policy and relevant laws were examined through a review of existing research literature. The results of the development process of the domestic distribution policy, promotion policies, and adjustment policies are summarized below. Results - The results are summarized as follows. First, the purpose of the development of the domestic distribution promotion policy was to strengthen the competitiveness of the small and medium business industry through structural advancement of the small and medium industry. By expanding the managerial base for the small and medium industry, a new balance could be created in the national economy. There was a requirement for an early assistance policy for small and medium businesses as a base of these businesses in the distribution industry developed from their original model of catering to a traditional market of retail shops. Since 1996, there was a need for this early assistance policy due to the expansion and rapid growth of large scale stores causing a change in the consumption pattern for distribution markets and the decline of large enterprises. Second, the government supports small and medium business distribution through distribution promotion policies by supporting an organization promoting small business and supporting innovation in the distribution system. Third, in 1961 a business mediation system was established to protect small and medium industries. The Small and Medium Business Administration advises conglomerates to postpone acquisitions, restrain expansion of the business, or to reduce business scale if small businesses undergo an adverse effect such as decreasing demand because large companies are expanding into their areas. Fourth, the Distribution Adjustment Policy managed large-scale store regulation as follows: ① limitation on construction by urban planning ordinance, ② limitation on location based on traffic impact assessments, ③ regulation based on business guidelines by chiefs of autonomous bodies, ④ regulation on mandatory holidays and limitation of business hours. This large-scale store regulation is a policy introduced by authority to increase competitiveness of small and medium business distribution by the government. Conclusions - As discussed in this study, the distribution promotion policy and distribution adjustment policy are government distribution policies focused on the protection of the small and medium distribution businesses. This study is timely, since it was planned when the strengthening of the revisions of the Distribution Industry Development Act, aimed to protect small and medium retailers and merchants, was under discussion. The significance of this study is that it offers insights for the development of new policies in the future and an opportunity to consider the background of the distribution policy by the government.

• The Journal of the Korea Contents Association
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• v.8 no.5
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• pp.246-259
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• 2008

This study was to minimize the trial and error in the primary step of the C4I system(ATCIS) of the each army corps on the front line, and test the economy and efficiency was tested by reviewing related papers and the system characteristics of other countries. The relationship was researched by analyzing the collected survey data and survey data related to the user's requirement level such as the army standards, that is, commonality, timeliness, simplification, automaticity, field availability and viability, multi-stage security and interoperability, unification. The result showed that the C4I system was efficiently operated through the system reliability for the specification of the system and operation manual, maneuverability and security, adaptability of the war field and system support and management, and good education and training about system operation, and less system maintenance and supplementary element. As a result, the development plan confirmed that the continuous operator education and the construction of the maintenance, and the upgrade digitalization(C4ISR+D) with the korean characteristics based on IT of network systems, and system development of the measurement model of the operator performance must be continuously supplemented in the near future.

• Tunnel and Underground Space
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• v.29 no.6
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• pp.456-467
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• 2019

In this study, the discrete element method was used to simulate the excavation of spoke-type shield TBM. The horizontal stress coefficient was used for the ground to simulate the increase of the horizontal stress according to the depth, and the driving conditions were set based on the torque generated from the cutterhead of the TBM to excavate within the operating range. That is, when the value of the torque generated at the cutterhead exceeds the given operating condition, the speed of excavation is constantly reduced, and conversely, the method of increasing the speed of excavation is considered. The change speed of the excavation was given the minimum change requirement in consideration of the driver's review time, and the change was possible according to the excavation conditions. In order to use these conditions, the user-subroutine was considered separately, and the results show that the DEM model were able to analyze the excavation within the considered operating range.