• Steel and Composite Structures
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• 제25권3호
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• pp.299-314
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• 2017

The aim of this paper is to investigate the performance of Lightweight Aggregate Concrete Filled Steel Tube (LWCFST) columns experimentally and compare to the behavior of Self-Compacted Concrete Filled Steel Tube (SCCFST) columns under axial loading. Four different L/D ratios and three D/t ratios were used in the experimental program to delve into the compression behaviours. Compressive strength of the LWC and SCC are 33.47 MPa and 39.71 MPa, respectively. Compressive loading versus end shortening curves and the failure mode of sixteen specimens were compared and discussed. The design specification formulations of AIJ 2001, AISC 360-16, and EC4 were also assessed against test results to underline the performance of specification methods in predicting the compression capacity of LWCFST and SCCFST columns. Based on the behaviour of the SCCFST columns, LWCFST columns exhibited different performances, especially in ductility and failure mode. The nature of the utilized lightweight aggregate led to local buckling mode to be dominant in LWCFST columns, even the long LWCFST specimens suffered from this behaviour. While with the SCCFST specimens the global buckling governed the failure mode of long specimens without any loss in capacity. Considering a wide range of column geometries (short, medium and long columns), this paper extends the current knowledge in composite construction by examining the potential of two promising and innovative structural concrete types in CFST applications.

• Steel and Composite Structures
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• 제25권4호
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• pp.427-442
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• 2017

This paper presents unprecedented damped oscillation behaviours of a precast steel-concrete composite slab panel for track support. The steel-concrete composite slab track is an innovative slab track, a form of ballastless track which is becoming increasingly attractive to asset owners as they seek to reduce lifecycle costs and deal with increasing rail traffic speeds. The slender nature of the slab panel due to its reduced depth of construction makes it susceptible to vibration problems. The aim of the study is driven by the need to address the limited research available to date on the dynamic behaviour of steel-concrete composite slab panels for track support. Free vibration analysis of the track slab has been carried out using ABAQUS. Both undamped and damped eigenfrequencies and eigenmodes have been extracted using the Lancsoz method. The fundamental natural frequencies of the slab panel have been identified together with corresponding mode shapes. To investigate the sensitivity of the natural frequencies and mode shapes, parametric studies have been established, considering concrete strength and mass and steel's modulus of elasticity. This study is the world first to observe crossover phenomena that result in the inversion of the natural orders without interaction. It also reveals that replacement of the steel with aluminium or carbon fibre sheeting can only marginally reduce the natural frequencies of the slab panel.

• 대한산업공학회지
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• 제37권1호
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• pp.19-29
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• 2011

Cellular network is comprised of several base stations which serve cellular shaped service area and each base station (BS) is connected to the mobile switching center (MSC). In this paper, the configuration modeling and algorithm of a cellular mobile network with the aim of minimizing the overall cost of operation (handover) and network installation cost (cabling cost and installing cost of mobile switching center) are considered. Handover and cabling cost is one of the key considerations in designing cellular telecommunication networks. For real-world applications, this configuration study covers in an integrated framework for two major decisions: locating MSC and assigning BS to MSC. The problem is expressed in an integer programming model and a heuristic algorithm based on Lagrangian relaxation is proposed to resolve the problem. Searching for the optimum solution through exact algorithm to this problem appears to be unrealistic considering the large scale nature and NP-Completeness of the problem. The suggested algorithm computes both the bound for the objective value of the problem and the feasible solution for the problem. A Lagrangian heuristics is developed to find the feasible solution. Numerical tests are performed for the effectiveness and efficiency of the proposed heuristic algorithm. Computational experiments show that the performance of the proposed heuristics is satisfactory in the quality of the generated solution.

• Structural Engineering and Mechanics
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• 제8권1호
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• pp.85-102
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• 1999

With the advent of computer, the finite element method has become a most powerful numerical method for structural analysis. However, bridge designers are reluctant to use it in their designs because of its complex nature and its being time consuming in the preparation of the input data and analyzing the results. This paper describes the development of a computer based finite element model using the idea of eccentric beam elements for the analysis of slab-on-girder bridges. The proposed method is supported by a laboratory test using a reinforced concrete bridge model. Other bridge analytical schemes are also introduced and compared with the proposed method. The main aim of the comparison is to prove the effectiveness of the shell and eccentric beam modelling in the studies of lateral load distribution of slab-on-girder bridges. It is concluded that the proposed finite element method gives a closer to real idealization and its developed computer program, SHECAN, is also very simple to use. It is highly recommended to use it as an analytical tool for the design of slab-on-girder bridges.

• 동의생리병리학회지
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• 제21권5호
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• pp.1065-1071
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• 2007

It has been known that Asian Medicine theory are based on yin and yang & Five Phases. but recently many therapist using asian medicine in Korea or another nations, take up the position that it is not inevitable for them to adopt the theory of yin-and-yang & Five Phases when they cure a patient. but the point of this view suggests they can not understand totally the real theory about yin-and-yang & Five Phases. asian image-mathematics based on I-Ching could analysis all things with the natural number. the kernel of understanding on principle of I-Ching is realizing that the standard should be changed in some conditions and the form of cosmos should change endless. the system of all thing under sun is divided in three parts on the asian image-mathematics. the nature number from one to nine is divided in three categories that are grouped as 123, 456, 789. So, if we want to understand Five Phases theory, we suggest that it is useful to know the organic connected relations among Four Images, Five Phases, Six Qi(six kinds of weather). the aim of this paper is to arrive at understanding of profound learning on image-mathematics throughout the number of 4, 5, 6 in the concrete context.

• 공업화학
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• 제30권5호
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• pp.586-590
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• 2019

The aim of this study was to fabricate a dextran polyelectrolyte multi-layer on a bare metal stent (BMS) and to evaluate bio-physical properties of the layer. Diethylaminoethyl-dextran (DEAE-D) as a polycation and dextran sulfate (DS) as a polyanion were successively coated on the bare metal stent by a well-known layer-by-layer procedure. The morphology of the stent surface and its cell adhesion were studied after each coating step by scanning electron microscopy. The stent showed more blotched and slightly rougher morphology after dextran-DS coating. The contact angle of the DEAE-DS group ($39.5{\pm}0.15^{\circ}$) was significantly higher than that of the BMS group ($45.16{\pm}0.08^{\circ}$), indicating the improvement of hydrophilic. The SMC proliferation inhibition in the DEAE-DS-coated stent group ($20.9{\pm}0.04%$) was stronger than that in the control group ($21.7{\pm}0.10%$ in DS-coated group only). The DEAE-DS coating is desired for stent coating materials with biocompatibility and anti-restenosis effect.

• 무역상무연구
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• 제68권
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• pp.171-195
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• 2015

The large increase in RTAs since the late 1980's has challenged the foundations of the multilateral trading system, and thereby has become an axis in the GATT/WTOsystem.While RTAs can be seen to be contradictory to the overall aim of the WTO, they were allowed for in Article XXIV of GATT conditional to certain provision. The failure of compliance and subsequently enforcement of these provisions could be seen as a serious flaw of Article XXIV since the inception of GATT system. Many elements of GATT Article XXIV are not clear and thus lead to divergent interpretations of its disciplines. This considerable divergence in opinions arise from both ambiguities throughout the provisions under GATT Article XXIV. In this regard, both economic and legal work is required to keep up with constantly changing nature of the world trading system. Further, global efforts are required to resolve another teething issue of WTO's problematic institutional framework on GATT/WTO's oversight and surveillance of RTAs. and thereby strengthen the multilateral trading system. Needless to say, theGATT/WTOframework has been essential in paving the way for RTAs while ensuring a more multilateral and liberal trading system. Consequently, global efforts should be made to restructure the WTO for the renewed multilateral trade liberalization in the GATT/WTO.

• Safety and Health at Work
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• 제5권3호
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• pp.147-151
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• 2014

Background: Agriculture ranks among the most dangerous trades worldwide. There is, however, still a lack of knowledge on nonfatal injuries in agriculture. The aim of this study was to describe the nature and occurrence of nonfatal injuries in farmers in two counties in central Norway. Methods: A questionnaire was sent to 7,004 farmers in Norway. We asked for information about the respondents and the farm, whether the farmer had had work-related injuries on the farm during the past 12 months, and details about the incidence and seriousness of the injury. Results: A total of 2,699 respondents gave a response rate of 42%. Of the respondents, 249 (9.2%) reported one or more work-related injuries. The most usual cause of injury involved an animal, and >75% of these happened inside the outbuilding. Among these, 17.5% had a consequence of sick leave or a more serious result. When all the accidents were analyzed by stepwise logistic regression, only the variables: works alone, has >3,500 stipulated working hours at the farm, and the type of production were statistical significant explanatory variables for having an injury. Conclusion: Incorporating safety aspects to a greater extend in the design and construction of outbuildings would make a substantial contribution to injury prevention in agriculture.

• International Journal of Advanced Culture Technology
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• 제9권2호
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• pp.106-117
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• 2021

The aim is to find cyber measures in consideration of physical CPTED in order to prepare countermeasures for cybercrime prevention. For this, the six applied principles of CPTED were used as the standard. A new control item was created in connection with the control items of ISO27001. A survey was conducted on former and current investigators and security experts. As a result of the reliability analysis, the Kronbar alpha coefficient value was 0.947, indicating the reliability of the statistical value. As a result of factor analysis, it was reduced to six factors. The following are six factors and countermeasures. Nature monitoring blocks opportunities and strengthens business continuity. Access control is based on management system compliance, personnel security. Reinforcement of territoriality is reinforcement of each wife and ethics. Establishment of security policy to enhance readability, security system maintenance. Increasing usability is seeking ways to utilize, periodic incentives. For maintenance, security education is strength and security-related collective cooperation is conducted. The differentiation of this study was to find countermeasures against cybercrime in the psychological part of the past. However, they approached to find in cyber measures. The limitation of the study is to bring the concept of physical CPTED to the cyber concept.

• The Journal of Asian Finance, Economics and Business
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• 제7권12호
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• pp.1123-1132
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• 2020

The aim of this paper is to understand the nature of transformation of the Chinese economy. China's approach to the process of economic development in the aftermath of the reforms in the late 1970's has been a success story and a phenomenon of great significance. It helped millions of people move out of poverty and achieve an acceptable standard of life. The economic policy of China was more effective than India's; we measured this effectiveness in terms of two fundamental approach: first, growth was fundamental for ensuring and increasing the wellbeing as it increases total output in China compare to India; second, growth was pro-poor in China, but not in India, during the period 2000-2011. In this paper, we seek to explain how China reduced extreme poverty through reforms, and this reform experience of China stands out for three reasons. The first is renewed thrust on the rural economy and private sector, second is decentralized planning, and third is investment in human resource development. This experience of China's reform success offers a significant lesson for most of the developing countries, especially India, since India has more similarities with China. Therefore, this experience is particularly insightful for India.