• The Transactions of the Korean Institute of Power Electronics
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• v.18 no.6
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• pp.556-564
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• 2013

This paper proposes an initial rotor position detecting algorithm of a PM synchronous motor using an incremental encoder. The proposed algorithm estimates the phase offset between the rotor magnetic flux and the Z-pulse of the incremental encoder by applying six aligning mode current control. The absolute rotor position for driving a PM synchronous motor is calculated by using the phase offset of the Z pulse and A, B pulse signals of the encoder. The PMSM drives based on the estimated rotor position is applied to the elevator door system. The door length is measured on line at first setup of the elevator. The speed control for open, close, and reopen of the elevator door is also presented and the proposed algorithm for the elevator door system is verified by experiment.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.3
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• pp.134-140
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• 2018

This paper describes the design and fabrication of an automatic alignment and loading system for workpieces. To move a workpiece to a chucking position of a machine tool using a gantry robot, an automatic aligning device is required to load the workpiece before machining and automatically align them. The automatic alignment system was conceptually designed, and the structural analysis was performed for the main parts such as the top plate, center support, front and back support, and support shaft. Based on the structural analysis results, the size of these structures was determined. The automatic alignment system was manufactured, and the vertical movement characteristics of the workpiece up-and-down movement device and the rotation characteristics of the workpiece rotation device were experimentally examined. The result has confirmed that they operate normally.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.11
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• pp.134-141
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• 2003

An industrial product is designed and fabricated, followed by the inspection process in order to check whether it is dimensionally tolerable or not. The machining process produces a part such as a mold or die, in which the three-dimensional coordinate might be measured by a CMM (Coordinate Measuring Machine) for assessment of its dimension. It is not ignorable, however, that a CMM measurement requires a lot of operating time and cost, which has led to many studies on the OMM system. The OMM system can be categorized into contact and non-contact types, and each of which has its own strengths and weaknesses. Non-contacting types generally utilize structured lights, sounds or magnetic fields. Though they show rather poor performance in positional accuracy, the measuring speed is faster than the contacting probes. This paper presents the development of an OMM system based on a non-contacting laser displacement sensing apparatus and CAD model. The system is composed of software modules of center-aligning and measuring, which has been operated and verified on a NC machining center on a shop floor.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1073-1085
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• 2012

Soil microbial communities are immensely diverse and complex with respect to species richness and community size. These communities play essential roles in agricultural soil because they are responsible for most of the nutrient cycles in the soil and influence the plant diversity and productivity. However, the majority of these microbes remain uncharacterized because of poor culturability. Next-generation sequencing techniques have revolutionized many areas of biology by providing cheaper and faster alternatives to Sanger sequencing. Among them, amplicon pyrosequencing is a powerful tool developed by 454 Life Sciences for assessing the diversity of complex microbial communities by sequencing PCR products or amplicons. This review summarizes the current opinions in amplicon sequencing of soil microbial communities, and provides practical guidance and advice on sequence quality control, aligning, clustering, OTU- and taxon-based analysis. The last section of this article includes a few representative studies conducted using amplicon pyrosequencing.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.3
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• pp.310-318
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• 2016

The demands for vehicle safety systems such as ABS and ESC have been increased. Accurate vehicle state estimation is required to realized the abovementioned systems and tire-friction coefficient is crucial information. Estimation of lateral tire-road friction coefficient using pneumatic trail information is mainly dealt in this paper. Pneumatic trail shows unique characteristics according to the wheel side slip angle and these property is highly sensitive to vehicle lateral motion. The proposed algorithm minimizes the use of conventional tire models such as magic formula, brushed tire model and Dugoff tire model. The pure side slip maneuver, which means no longitudinal dynamics, is assumed to achieve the ultimate goal of this paper. A simulation verification using Carsim and Simulink is performed and the results show the feasibility of the proposed algorithms.

• Bulletin of the Korea Photovoltaic Society
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• v.6 no.1
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• pp.21-34
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• 2020

Sri Lanka has strongly understood the importance of mitigation of climate change and various measures have been taken. To tackle the climate change, after ratifying Paris Agreement, Sri Lanka has pledged to reduce her greenhouse gas emission in the energy sector by 20% (16% unconditional and 4% conditional) by 2030 based on the BAU scenario. Simultaneously, the government introduced its new energy policy and strategies in 2019 with a vision of achieving carbon neutrality by 2050. This paper survey related key government documents, policies, reports, and academic articles to investigate opportunities for the private sector to invest large scale solar power deployment (10 MW or above) and to get support from climate finance under article 6 of the Paris Agreement. It has found, growing concern on the environment, energy security issues and increase import expenses for fossil fuels are the main influencing factors to move renewable sources. Further, government investment and FDI both have gradually decreased in the energy sector. Therefore, an alternative financing mechanism is needed. Although the private sector allowed investing in the energy sector since 1996 with the introduction of IPP (Independent Power Producers), it could not make considerable progress on involving large scale solar utility projects. This has revealed government policy is not aligning with the long term generation plan of the electricity sector. The study has also found, it needs more strategic road map, coordination with different institutions, monitoring system to enhance large scale solar contribution.

• Journal of Satellite, Information and Communications
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• v.10 no.2
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• pp.75-79
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• 2015

In this study, we investigated the electro-optical (EO) characteristic of fringe-field switching (FFS) mode cell by the ion beam alignment method on the a-C:H thin film. The suitable inorganic thin films for FFS cell and the aligning capabilities of nematic liquid crystal (NLC) using the new alignment material of a-C:H thin film were studied. 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 a-C:H thin films. Also, the V-T hysteresis characteristics of the ion beam-aligned FFS-LCD with IB exposure on the a-C:H thin films is almost the same as that of the rubbing-aligned FFS cell on a polyimide surface.

• The Journal of Asian Finance, Economics and Business
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• v.4 no.2
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• pp.25-36
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• 2017

Subsidies are an instrumental policy making tool for many governments, but their importance depends on the market situation of the national economy. Efficient subsidy implementation would allow the government to correct market failure thereby aligning social and private costs and benefit. The general objective of this study is to justify the need to rationalise subsidies for food items such as flour. This study assessed the structure and conducts of the general purpose flour market in Malaysia; and analysed the impact of subsidies on market performance to recommend policies to increase market efficiency under the subsidy rationalisation program. To accomplish these objectives, the study adopted a microeconomics market analysis as well as the standard structure and performance analysis method. These two approaches showed the characteristics of an industry's consumer behaviour, competition, as well as the efficiency associated with government regulatory policies on the flour industry. One of the biggest influences on the domestic market is related to the food consumption behaviour of the general population. Food consumption behaviour reflects global trends. As income rises, food trends tend to be consumed in processed form or in such a way that adds value in another manner such as the preparation of food products.

• Journal of Distribution Science
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• v.15 no.7
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• pp.19-24
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• 2017

Purpose - There are several problems that organizations face to make a better team-based system such as free-rider issue, assigned difficult jobs unfairly and bickering between high performers and average performers. The purpose of this study is to provide solutions for practitioners through past academic studies on how organizations can resolve several issues in team management. Ultimately, it would lead to employees as better performers for organization's profitability and customers' satisfaction. Research design, data, and methodology - Solution 1 - put employees who have a similar performance ability together into a same team and apply 'growth' approach for low performance team. Solution 2 - make a new evaluation system which is balanced between individual's performance and team's performance. Solution 3 - monitor thoroughly to diffuse difficult works equally among teams and develop management practice system that may prevent or resolve difficult work-loads for a team or an individual performer. Result - Investigation suggests that organizations may resolve three conflicts which come from team base system. Moreover, the implications of results show that the most important criteria in team management depend on whether performers have a similar ability in the same team and management handles issue of justice and the performance of each employee is evaluated by total team performance evaluation simultaneously. Conclusions - All in all, our recommendation concludes that if three issues are resolved, the lack of trust in team-based system among team members will be missed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.280-281
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• 2006

We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of a Titanium dioxide ($TiO_2$) thin film by rf magnetron sputtering system for 15min under various rf power. A very low pretilt angle by ion beam exposure on the $TiO_2$ thin film was measured. A good LC alignment by the ion beam alignment method on the $TiO_2$ thin film surface was observed at annealing temperature of $200^{\circ}C$, and the alignment defect of the NLC was observed above annealing temperature of $250^{\circ}C$. Consequently, the low NLC pretilt angle and the good thermal stability of LC alignment by the ion beam alignment method on the $TiO_2$ thin film by sputter method as various rf power condition can be achieved.