• Structural Engineering and Mechanics
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• v.22 no.3
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• pp.371-399
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• 2006

The theoretical background and capabilities of the developed program, SAR-CWF, for stochastic analysis of 3D reinforced-concrete shear wall-frame structures subject to seismic excitations is presented. Incremental stiffness and strength properties of system members are modeled by extended Roufaiel-Meyer hysteretic relation for bending while shear deformations for walls by Origin-Oriented hysteretic model. For the critical height of shear-walls, division to sub-elements is performed. Different yield capacities with respect to positive and negative bending, finite extensions of plastic hinges and P-${\delta}$ effects are considered while strength deterioration is controlled by accumulated hysteretic energy. Simulated strong motions are obtained from a Gaussian white-noise filtered through Kanai-Tajimi filter. Dynamic equations of motion for the system are formed according to constitutive and compatibility relations and then inserted into equivalent It$\hat{o}$-Stratonovich stochastic differential equations. A system reduction scheme based on the series expansion of eigen-modes of the undamaged structure is implemented. Time histories of seismic response statistics are obtained by utilizing the computer programs developed for different types of structures.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.927-939
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• 2020

This study aims at investigating the effects of internal control effectiveness on business survival of food businesses in Thailand through the mediators of productivity improvement and value creation. In this study, 155 food businesses in Thailand are the samples of the study. The results show that internal control effectiveness has a significant influence on productivity improvement and business survival. Productivity improvement critically affects value creation and business survival while value creation is an important determinant of business survival. However, internal control effectiveness has no relationship with value creation. Also, productivity improvement explicitly mediates the internal control effectiveness-business survival relationships. In summary, internal control effectiveness can enhance firms' sustainable competitive advantage, superior performance and long-term survival. Firms need to focus on internal control effectiveness through investing their assets and resources and utilizing their abilities, competencies and capabilities in order to continuously develop and improve their appropriate concepts and characteristics in an organization. Better internal control effectiveness definitely leads to more long-term survival. To generalize the research results, future research needs to collect data from other businesses and industries. Increased response rate of the study is important for future research to verify and confirm the research results.

• Steel and Composite Structures
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• v.37 no.3
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• pp.341-351
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• 2020

Steel plate shear wall with self-centering energy dissipation braces (SPSW-SCEDB) is a lateral force-resisting system that exhibits flag-shaped hysteretic responses, which consists of two pre-pressed spring self-centering energy dissipation (PS-SCED) braces and a wall plate connected to horizontal boundary elements only. The present study conducted a series of cyclic tests to study the hysteretic performances of braces in SPSW-SCEDB and the effects of braces on the overall hysteretic characteristics of this system. The SPSW-SCEDB with PS-SCED braces only exhibits excellent self-centering capability and the energy loss caused by the large inclination angle of PS-SCED braces can be compensated by appropriately increasing the friction force. Under the combined effect of the two components, the SPSW-SCEDB exhibits a flag-shaped hysteretic response with large lateral resistance, good energy dissipation and self-centering capabilities. In addition, the wall plate is the primary energy dissipation component and the PS-SCED braces provide supplementary energy dissipation for system. The PS-SCED braces can provide up to 90% self-centering capability for the SPSW-SCEDB system. The compressive bearing capacity of the wall plate should be smaller than the horizontal remaining restoring force of the braces to achieve better self-centering effect of the system.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.3
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• pp.177-184
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• 2018

In case that limited resources can be mobilized, non-structural countermeasures such as 'monitoring using Information and Communication Technology might be one of solutions to mitigate disaster risks. Having established the monitoring system, operational and maintenance costs to maximize the effectiveness might trouble the authority concerned or duty attendant who is in charge. In this respect, "Guerrilla Sensor" would be very cost effective because of the inherent mobility characteristic. The sensor device with the IRIS camera and GPS (Global Positioning System) equipped, is basically battery-operated and communicates with WCDMA (Wideband Code Division Multiple Access). It has a strong advantage of capabilities for 'Disaster Response' with immediate and prompt action on the spot, making the best use of IoT (Internet of Things), especially with the mobile web. This paper will explain how the sensor system works in real-time GIS (Geographic Information System) pinpointing the exact location of the abnormal movement/ground displacement and notifying the registered users via SMS (Short Message Service). Real time monitoring with early warning and evaluation of current situations with LBS (Location Based Service), live image and data information can help to reduce the disaster impact. Installation of Guerrilla sensor for a real site application at Gimcheon, South Korea is also reported.

• Journal of KIBIM
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• v.6 no.4
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• pp.9-17
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• 2016

Currently whole-house refurbishment for substantial energy efficiency improvement of existing housing stock is needed to achieve the targeted 80% CO2 emission reduction. As whole-house refurbishment requires a larger capital investment for lower CO2 emission, the simultaneous use of Life Cycle Costing (LCC) and Life Cycle Assessment (LCA) methodologies are recommended to generate affordable refurbishment solutions. However, two methodologies are difficult to use due to a lack of proper LCC and LCA datasets. As a response to the current problems, many researchers explore potentials in Building Information Modelling (BIM) to improve current construction practice. As a result, a BIM tool - IES IMPACT (Integrated Material Profile And Costing Tool) - has been introduced to the UK construction industry for simultaneous calculation of LCC and LCA. Thus, this research aims at examining the capability and limitation of the IES VE/IMPACT as a BIM tool for whole-house refurbishment. This research reveals that the IES VE/IMPACT is feasible for whole-house refurbishment by providing LCC and LCA information simultaneously for informed decision on refurbishment solution selection. This research shed lights on the current problems lying on the data exchange between two different BIM tools. It is revealed that additional efforts from construction professionals and industry are required to make reliable BIM objects library with LCC and LCA datasets.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.1132-1136
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• 2004

In this paper, we intend to make FFS mode cell with LC alignment used non-rubbing method, ion beam alignment method on the a-C:H thin film, to analyze electro-optical characteristics in this cell. We studied on the suitable inorganic thin film for FFS-LCD and the aligning capabilities of nematic liquid crystal (NLC) using the new alignment material of a-C:H thin film as working gas at rf bias condition. A high pretilt angle of about 5$^{\circ}$ by ion beam(IB) exposure on the a-C:H thin film surface was measured. An excellent voltage-transmittance (V-T) and response time curve of the ion-beam-aligned FFS-LCD was observed with oblique ion beam exposure on the DLC thin films.

• Research in Mathematical Education
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• v.12 no.4
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• pp.283-291
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• 2008

The extension to a wide population of secondary education in many advanced countries seems to have led to a weakening of the mathematics curriculum. In response, many students have been classified as "gifted" so that they can access a stronger program. Apart from the difficulties that might arise in actually determining which students are gifted (Is it always clear what the term means?), there are dangers inherent in programs that might be devised even for those that are truly talented. Sometimes students are moved ahead to more advanced mathematics. Elementary students might be taught algebra or even subjects like trigonometry and vectors, and secondary students might be taught calculus, differential equations and linear algebra. It is my experience over thirty-five years of contact with bright students that acceleration to higher level mathematics is often not a good idea. In this paper, I will articulate some of the factors that have led me to this opinion and suggest alternatives. First, I would like to emphasize that in matters of education, almost every statement that can be made to admit counterexamples; my opinion on acceleration is no exception. Occasionally, a young Gauss or Euler walks in the door, and one has no choice but to offer the maximum encouragement and allow the student to go to the limit of his capabilities. A young genius can demonstrate an incredible amount of mathematical insight, maturity and mastery of technique. A classical example is probably the teen-age Euler, who in the 1720s was allowed regular audiences with Jean Bernoulli, the foremost mathematician of his day.

• Transactions on Electrical and Electronic Materials
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• v.8 no.6
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• pp.274-277
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• 2007

In this study, liquid crystal(LC) aligning capabilities for homeotropic alignment on the $SiO_x$ thin film by electron beam evaporation method were investigated. Also, the control of pretilt angles and thermal stabilities of the nematic liquid crystal(NLC) treated on $SiO_x$ thin film were investigated. A high pretilt angle of about $86.5^{\circ}$ was obtained, and also the suitable pretilt angle of the NLC on the $SiO_x$ thin film at $10{\sim}50nm$ thickness with e-beam evaporation can be achieved. The uniform LC alignment and good thermal stabilities on the $SiO_x$ thin film surfaces with electron beam evaporation can be achieved. It is considered that the LC alignment on the $SiO_x$ thin film by electron beam evaporation is attributed to elastic interaction between LC molecules and micro-grooves at the $SiO_x$ thin film surface created by evaporation.

• Journal of Power System Engineering
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• v.17 no.6
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• pp.130-135
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• 2013

It is a research about the change in reduction efficiency and performance resulting from installation of the EGR cooler, which is the core technology reducing NOx in response to standards been tightened of exhaust controls for off-road vehicle. It can reduce NOx by altering combustion temperature and oxygen concentration by recycling high-temperature exhaust gas. The target engine was large diesel engine for construction machine through by which we were able to verify a rate of change in output and capabilities for a heat-exchange within cooler itself depending on the existence of EGR cooler system. We have acquired a emission reduction technology for a construction machine by testing the reduction performance and rate of change in output.

• Earthquakes and Structures
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• v.9 no.4
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• pp.735-752
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• 2015

The effectiveness of seismic retrofitting of RC-frame buildings by converting selected bays into new walls through infilling with RC walls was studied experimentally using a full-scale four-storey model tested with the pseudo-dynamic (PsD) method. The frames were designed and detailed for gravity loads only using different connection details between the walls and the bounding frame. In order to simulate the experimental response, two numerical models were formulated differing at the level of modelling. The purpose of this paper is to illustrate the capabilities of these models to simulate the experimental nonlinear behaviour of the tested RC building strengthened with RC infill walls and comment on their effectiveness. The comparison between the capacity, in terms of peak ground acceleration, of the strengthened frame and the one of the bare frame, which was obtained numerically, has shown a five-fold increase.