• ETRI Journal
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• v.36 no.4
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• pp.625-634
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• 2014

This paper studies a dual-hop multiple-access relay network where two independent source nodes transmit information to a common destination node with the aid of multiple single-antenna amplify-and-forward relays. Each relay node is subject to an individual power constraint. We focus on the design of distributed beamforming schemes for the relays to support the transmission rate requirements of the two sources. To this end, we first characterize the achievable rate region for this network via solving a sequence of corner point optimization problems proposed in this paper. We also develop several low-complexity suboptimal schemes in closed form. Two inner bounds of the achievable rate region are theoretically shown to be approximately optimal in two special scenarios. Finally, numerical results demonstrate the effectiveness of our proposed approaches.

• International Journal of Railway
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• v.1 no.4
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• pp.134-142
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• 2008

Serving as a strategic crossing point for major corridors in Central Europe, Railnet Austria's Infrastructure Network incurs continual increases in international traffic flows and is therefore subject to accumulating traffic congestion with potential restrictions to infrastructure access. This imposes challenges towards preserving open access to Railnet Austria's existing railway network and hinders quality infrastructure service during maintenance, repair, and upgrading. Through Railnet Austria's experiences, the economic viability of a railway network can be sustained through maintaining open access with good quality service of planned trainpaths, thus representing new challenges for future infrastructure maintenance and capacity planning. Railnet Austria's Capacity Management Department has proven that these challenges can be accommodated more effectively through recent technological developments in data warehousing and software development.

• Journal of Communications and Networks
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• v.8 no.3
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• pp.257-266
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• 2006

The powerful benefits of multi-antenna systems can be obtained by cooperative communications among users in multiple access environments without the need for physical arrays. This paper studies a novel cooperative signaling strategy that achieves high performance and low implementation complexity for synchronous code division multiple access (CDMA) wireless mobile networks. The validity of the proposed strategy under slow flat Rayleigh fading channel plus additive white Gaussian noise (AWGN) is verified through closed-form error probability expressions and MonteCarlo simulations. A variety of analytical results reveal that the new cooperative strategy significantly outperforms direct transmission subject to the same spectral efficiency and transmit power constraint.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.3
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• pp.303-309
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• 2022

The goal of this research is to examine how credit (loan) can help rural households in Tra Vinh province create jobs in the wake of the COVID-19 outbreak in Vietnam over the last two years. The authors performed a direct survey, using a questionnaire, with 300 customers who had loan records at the Tra Vinh VBSP branch under the loan programs. From January to April 2021, jobs will be available at 07 transaction offices in districts and cities (Cau Ngang; Duyen Hai, Tieu Can, Cang Long, Tra Vinh City, Chau Thanh, Tra Cu). Using the multivariate regression method, the research has found 12 factors affecting the ability to access the employment loan program: Age, Educational Level, Occupation of households, Income, Household land area, Asset, Loan, Interest rates, Loan procedures, Loan purpose, Credit relations. From the above research results, the authors have proposed solutions to improve the ability to access credit to create jobs for each subject group at Viet Nam Bank for Social Policies, Tra Vinh Province in the future.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.23 no.2
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• pp.27-44
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• 2012

This paper provides suggestions for analyzing Cultural Objects Name Authority(CONA) developed by the Getty Trust and applying CONA to Functional Requirements for Subject Authority Data(FRSAD). CONA is linked with the other Getty controlled vocabularies such as AAT, ULAN, and TGN, and can be linked with the library controlled vocabularies, such as LCSH. However, CONA has differences with library models since CONA is based on the art museum or art gallery. Therefore, we need to consider it when we link CONA to library standard models. The results discussed in this study have implications for analyzing CONA which provides access for cultural objects and applying it to the FRSAD, the subject authority model in library fields.

• Journal of information and communication convergence engineering
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• v.8 no.6
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• pp.725-728
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• 2010

The subject collects information and constructs the outside world mainly through the sense of sight, though he cannot help but always see things from the viewpoint of the self-aware ego. While we are able to access the unconscious of which the latent desire is reflected in involuntary images and dream images, the substance of desire cannot be easily accessed due to the censorship of the ego and the super-ego, which makes images of the unconscious nonlinear, and allows us to pursue fantasies for pleasure. The original human desire to record and express visual objects has come true with technological fulfillments, and furthermore, digital technology has realized visual pleasure and desire, through simulation. The images that the unconscious produces and the images that digital technology produces are a visualization of objects by the subject's desire, and the subject realizes his pleasure through a visual fantasy. This study, based on the mechanism of the unconscious and the formal stamps of digital images, explores the interrelationship between the unconscious and digital images, both of which seek pleasure and desire.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.343-345
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• 2022

Computational thinking is a subject that must be selected by non-major freshmen at H University, and classes are completed regardless of their major. The class content is conducted using block coding that allows easy access to programming. A survey was conducted before the start of the semester class to find out the students' interest in the subject and to help the students understand it. This study analyzes the student's survey response data so that the students' interest in the subject can be grasped at a glance.

• The Transactions of the Korea Information Processing Society
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• v.7 no.11S
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• pp.3623-3632
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• 2000

Until now the XML document is allowed users to access the whole content of it However, for some applications such as those in the field of electronic commerce, there are cases that the whole content should not be delivered. Therefore, access authorization is required for XML documents in order to protect illegal accesses to some critical parts of them. In this paper. we design and implement a system which authorizes users to XML documents and controls access to them based on the access rights. We set the user group as a basic unit of the authorization subject and the element of an XML document as a basic unit of authorization object The owner of a document authorize; user groups to access the elements of it When an XML document is accessed, the access rights of the requester are checked using an access control list and only the authorized parts are delivered_ As the result, we can authorize XML documents, which has been previously impossible.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.33 no.1
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• pp.233-258
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• 2022

The purpose of this study is to identify elementary school teachers' needs for access points when searching for picture books to be used as teaching media, and suggest ways to improve DLS(Digital Library System) in school libraries. To achieve this purpose, the study examined the access points provided by OPAC(Online Public Access Catalog) systems in seven domestic and foreign libraries. In addition, it conducted an online survey with elementary school teachers, and a total of 220 responses were finally analyzed. It was found that the most needed access points were topic, grade/age, content, subject/chapter, and cross-curricula learning topics, etc. Based on the results, this study suggests providing the most needed access points in DLS, developing controlled vocabulary tools, and improving system functions or the interface to enhance accessibility to picture books.

• Journal of Distribution Science
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• v.15 no.7
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• pp.43-52
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• 2017

Purpose - This study investigates shopping behaviors and effects focusing on the seniors in 50s and 60s based on their buying satisfaction in online shopping. The study investigated causal relation between effects having influence upon online shopping behavior to give theoretical base on the use of online shopping. The study gave implications of consumption attitude of silver generation as well as senior consumers in aging society. Research design, data, and methodology - The subject was senior consumers who have experienced online shopping to be sensitive to the fashion and to have active and reasonable consumption pattern and to be active and to have positive value. Results - This study investigated the mediating effect on purchase satisfaction of the 50s and the 60s upon online shopping to examine online shopping use and effects. The subject was the ones in their 50s and 60s in Gyeonggi and Chungnam who had experienced online shopping. All of hypotheses of models at PLS analysis were supported. Conclusions - Both information innovation and self-satisfaction showed positive influence upon the ease of and also access of the use. In addition, the access to the use had positive influence upon the purchase intention in retailers' online shopping.