• The Journal of Korean Institute of Communications and Information Sciences
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• v.38A no.8
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• pp.712-723
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• 2013

Recent exploration of smart-phone user is fueling the deployment of long term evolution (LTE) service that offers higher data rates service over 3G HSPA networks. In particular, Korea, mobile powerhouse, recently launched the service of LTE-Advanced (LTE-A) which is the latest release in LTE standard. Multiple-input-multiple-output (MIMO) technology is the one of key enablers for LTE and LTE-A for achieving high data rate. MIMO technology has received much attention since it is possible to achieve channel capacity in proportion to the number of antennas without increasing frequency and power. In this paper, we overview of the theoretical background of MIMO technology regarding from single-user MIMO, multiuser MIMO, and massive MIMO and design considerations to implement the communication system.

• Journal of the Institute of Convergence Signal Processing
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• v.12 no.4
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• pp.281-285
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• 2011

One of the key issues in implementing RFID systems is to design anti-collision protocols for identifying all the tags in the interrogation zone of a RFID reader with the minimum identification delay. In this paper, Furthermore, in designing such protocols, the limited resources in tags and readers in terms of memory and computing capability should be fully taken into consideration. we first investigate two typical RFID anti-collision algorithms, namely RFID Gen2 Q algorithm (accepted as the worldwide standard in industrial domain) and FAFQ algorithm including their drawbacks and propose a new RFID anti-collision algorithm, which can improve the performance of RFID systems in terms of tag identification time considerably. Further, we compared performance of the proposed algorithm with Q algorithm and FAFQ algorithm through computer simulation.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.5
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• pp.185-194
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• 2020

The study aims to identify and measure factors affecting the perception of the selling price of luxury apartments in Hanoi. We conducted a questionnaire consisting of 29 observation variables with a 5-point Likert scale. Independent variables were measured from 1 "without effect" to 5 "strongly". Based on the desk review and results of interviews, a total of 500 questionnaires were sent to research participants for collection; 458 of them met standard and were subject to be analyzed. This study employs Cronbach's Alpha test, and regression model. The results of Exploratory Factor Analysis (EFA) and Multiple Regression Analysis (MRA) identify five main determinants influencing the perception of the selling price of luxury apartments in Hanoi, including Physical characteristics of a luxury apartment (PC); Location and position of an apartment (LP); Surrounding Area (SA); Quality of service provided by managers; (QS) and Demographics factor (DF). Based on the findings, some recommendations have been proposed to help the firm leaders design appropriate personnel policies for creating better price satisfaction for customers in the future. On this basis, the authors propose a number of recommendations to improve the quality of luxury apartments, thereby contributing to the development of the market for luxury apartments in Hanoi.

• Journal of Distribution Science
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• v.17 no.12
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• pp.71-79
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• 2019

Purpose: This study focuses on lean implementation evaluation in Third Party Logistics (TPL) industry by using the lean principles measurement from Toyota Ways which consist of 14 principles. The core goal of this study is to appraise the lean implementation level in Third Party Logistics in East Java of Indonesia in order to achieve efficient logistics, distribution and transportation activities. Research design, data and methodology: This study uses a sample of 80 respondent who are Third Party Logistics managers in East Java Province, Indonesia. Data collection uses a questionnaire and standard statistical test was performed in order to analyze questionnaire. Results: The implementation level of lean management in Third Party Logistics shows that application of principle 3 (utilizing pull systems) has a higher score than the other principles. This situation shows that management give the best performance in plan process. They prioritize customer requirement in every process designed. However, the principle 8 (using reliable technology) show the weakness performance. Conclusions: Overall, this study shows the Third Party Logistics in East Java Province of Indonesia have applied the lean principle quite well, although the scores are only slightly above the average. This condition provides a strong basis for further lean implementation, especially for improving logistics, distribution and transportation activities in Third Party Logistics Business.

• 한국공간정보시스템학회:학술대회논문집
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• 1999.06a
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• pp.35-45
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• 1999

기존에는 이질적인 GIS 데이타 소스간의 통합을 위해 랩퍼(wrapper)기술을 사용했다. 랩퍼(wrapper)는 외부 클라이언트 응용프로그램에게 이질적인 데이타 소스들의 통합 데이타 모델을 제공함으로써 데이타와 지리정보처리의 공유를 가능하게 한다. 그러나 데이타 소스들의 통합은 표준 서비스를 포함한 상호운용성을 지원하는 것은 아니다. 표준을 따르는 상호운용을 위해서는 표준화된 데이타 모델과 서비스가 필요한데 OGC (OpenGIS Consortium)의 OpenGIS(Open Geodata Interoperability Specification)가 이를 제공하고 있다. 분산환경에서 상호운용을 위한 기존방법은 각 데이타 소스별로 데이타 제공자를 개발하여 상호운용을 지원하였다. 따라서 중복 구현에 대한 문제와 구현에 따른 노력과 비용이 상당 부분 존재하였다. 본 논문에서는 데이타 제공자에서 공통부분을 추출 및 컴포넌트 화하고 데이타 소스에 종속되는 모듈은 CORBA 구현객체로 작성하여 제시하였다. 따라서 각 데이타 소스들은 표준 데이타 제공자를 통해서 기존의 데이타 지원 기능유지와 상호운용성을 달성할 수 있다. 클라이언트는 OpenGIS Feature모델을 기반으로 한 표준 인터페이스로 데이타 소스에 접근한다. 데이타 소스는 표준데이타 제공자와 정의된 인터페이스를 바탕으로 CORBA의 구현 객체 서버를 작성함으로서 중복구현 및 구현부담을 줄일 수 있다.

• 한국공간정보시스템학회:학술대회논문집
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• 1999.06a
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• pp.193-200
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• 1999

The major purpose of this study was to design a external metadata which fit domestic demands of the digital maps. For designing a standard external metadata reflecting the current trends of the international organizations on standardization, a prelimenary study was made mainly concentrating on the analysis of the standards of the developed countries. For better assessing domestic needs, all the metadata related material of the National Geography Institute were collected and classified based on the NGI's workflow. The external metadata draft was made considering the results from the analysis of the existing NGI material and the draft was also cited some major cores from the ISO standards. Continuous efforts should be made in the future to update the metadata draft based on the opinions from domestic users and the technical trends of the international organizations on standardization.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.6
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• pp.2104-2117
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• 2014

The propagation of smart devices and the rapid expansion of wireless mobile networks have increased the need for ubiquitous device connectivity and contents access. DLNA is currently being used as the de facto standard for connectivity of consumer devices in the digital home. The guidelines provided by DLNA are intended to facilitate device and contents discovery, management, sharing and distribution. However, consumer experience with DLNA has been rather poor and usability not up to speed. Different problems and issues in limited compatibility have been reported due to manufacturer customizations. Such compatibility issues are often difficult to identify by average consumers who are not savvy in information communications and multimedia technology. In this paper, the design and implementation of a DLNA protocol inspection tool is presented for compatibility analysis among DLNA certified devices. The tool monitors the home network and performs analysis of the underlying protocols used by DLNA. The tool can be used for diagnostics and troubleshooting, enabling the user to identify compatibility issues between devices or problems in the network.

• Journal of Applied Reliability
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• v.1 no.2
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• pp.121-138
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• 2001

Due to large demand for high speed and great capacity for data transfer, WDM, which uses the wavelength division multiplexing technique, is known as alternative way to satisfy those demand for its flexible network operation and management, easy network expansion with existing networks, and enhancement of efficient data transfer rate. For these reasons, a new high capacity WDM optical communication network plan was established. Therefore, the quality of currently deployed optical cables with 81.6 km in length should be assessed to ensure if high capacity WDM system could be implemented on existing optical cables. Two important characteristic parameters, Transfer Loss and PMD (Polarization Mode Dispersion), were measured to evaluate quality of existing optical cable. Transfer Loss was measured at 0.244 dB per kilometer, which is lower than the design standard value at 0.275 dB/km. The measured PMD value gave at 0.030ps/km, and it, therefore, satisfies the value recommended by ITU-T (International Telecommunication Union-T) of 0.5ps/km. In addition, the transfer characteristic for existing 2.5 Gbps and 10 Gbps system were measured and evaluated, and the results showed that error-free transfer is very much feasible. Computer simulation for DWDM system, which is likely be a future backbone network in Korea, to assess the transfer characteristic using the same condition employed for 2.5 Gbps and 10 Gbps was carried out as well. The simulation verified that a stable network operation and reliable service could be provided.

• Journal of the Korea Society of Computer and Information
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• v.5 no.2
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• pp.37-42
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• 2000

Object technologies like the OMG's CORBA are enabling technologies the aim to facilitate integration implementation of diverse software components in distributed. heterogeneous environment. CORBA and similar object integration technologies define a standard component interconnection and inter-operation model , promote object-oriented principles to encapsulate incompatible component implementations. In this Paper. we present a connector model for software architectural representation of complex component collaborations. Our Connector model is base on research in software achitecture and object-oriented modeling. and part of a design framework for modeling component-based system. We believe the connector concepts to be vary benificial for a clear expression of dependencies between multiple component in Java Bean-based system.

• Safety and Health at Work
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• v.4 no.3
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• pp.123-135
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• 2013

Exposure to manganese (Mn) is associated with neurobehavioral effects. There is disagreement on whether commonly occurring exposures in welding, ferroalloy, and other industrial processes produce neurologically significant neurobehavioral changes representing parkinsonism. A reviewof methodological issues in the human epidemiological literature onMnidentified: (1) studies focused on idiopathic Parkinson disease without considering manganism, a parkinsonian syndrome; (2) studies with healthy worker effect bias; (3) studies with problematic statistical modeling; and (4) studies arising from case series derived from litigation. Investigations with adequate study design and exposure assessment revealed consistent neurobehavioral effects and attributable subclinical and clinical signs and symptoms of impairment. Twenty-eight studies show an exposure-response relationship between Mn and neurobehavioral effects, including 11 with continuous exposure metrics and six with three or four levels of contrasted exposure. The effects of sustained low-concentration exposures to Mn are consistent with the manifestations of early manganism, i.e., consistent with parkinsonism. This is compelling evidence thatMnis a neurotoxic chemical and there is good evidence that Mn exposures far below the current US standard of $5.0mg/m^3$ are causing impairment.