• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.9
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• pp.809-818
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• 1991

We investigate the onsiderations of design issues for a bradband ATM network. Three kimds of network design requirement are considered ; user grade-of-service(GOS) requirements. Network manager requirements, and system designer requirements. In this work, e are focusing on the balancing problems among performance measures. We suggest that design parameters for a bradband ATM echange would be tuned within the acceptable sets by a layering concept on the peformance objectives.

• ETRI Journal
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• v.29 no.1
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• pp.120-123
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• 2007

In this letter, we address the problem of resource allocation with efficiency and quality of service (QoS) support in uplink for a wireless CDMA network supporting real-time (RT) and non-realtime (NRT) communication services. For RT and NRT users, there are different QoS requirements. We introduce and describe a new scheme, namely, traffic aided uplink opportunistic scheduling (TAUOS). While guaranteeing the different QoS requirements, TAUOS exploits the channel condition to improve system throughput. In TAUOS, the cross-layer information, file size information, is used to improve fairness for NRT users. Extensive simulation results show that our scheme can achieve high system throughput in uplink wireless CDMA systems, while guaranteeing QoS requirements.

• Journal of Positioning, Navigation, and Timing
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• v.12 no.4
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• pp.431-436
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• 2023

In order to provide continuous Korea Augmentation Satellite System (KASS) services, the operation organization should continuously and systematically perform operations, maintenance, and technical activities. All subsystems of KASS, all Line Replacement Units (LRUs), and Software Replacement Units (SWRUs) should be operated and maintained continuously. In order to effectively manage these activities, it is necessary to develop an Operation Management Tool (OMT). For this purpose, operation management, operation organization, and operation activities were defined. The defined requirements were divided into general, function, interface, and database for OMT development, and functions and decision-making procedures consisting of site/asset/trouble/work order/schedule management were designed. The OMT developed by reflecting the site and asset information as well as the design content met predefined requirements. The OMT will be actively used in actual KASS operation and will evolve by continuously reflecting the additional requirements of operators. Through this tool, KASS will support continuous service provision.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.36 no.4
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• pp.38-44
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• 2013

Smart phones have brought rapid changes in this competitive world. Smart phone application developers are trying their best to consider the customer requirements in the most efficient way while considering all its attributes. However smart phone service quality has been given less consideration comparatively during the last few years. This paper proposes a measurement method for improving service quality of smart phone application. This method combines the service quality performance model (SQPM) and process capability index (PCI). The service quality performance model is used to identify service items that require improvement. Process capability index is used as a measure for prioritization of those improvements. Case study was carried out to search out important communication application service attributes. customer satisfaction level data was collected for users who used the application service. A total of twenty four service attributes were found during this survey. Using the joint approach of SQPM and PCI, five significant service attributes were prioritized for service quality improvement.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.3
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• pp.1260-1281
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• 2015

As the number of services available on the Web increases, it is vital to be able to identify which services can be trusted. Since there can be an extremely large number of potential services that offer similar functionality, it is challenging to select the right ones. Service requestors have to decide which services closelysatisfy their needs, and theymust worry about the reliability of the service provider. Although an individual service can be trusted, a composed service is not guaranteed to be trustworthy. In this paper, we present a trust model that supports service discovery and composition based on trustworthiness. We define a method to evaluate trust in order to discover trustworthy services. We also provide a method to perform trust estimation for dynamic service composition, and we present results of two experiments. The proposed model allows for service requestors to obtain the most trustworthy services possible. Our mechanism uses direct and indirect user experience to discover the trustworthiness of the services and service providers. Moreover, composing services based on quantitative trust measurements will allow for consumers to acquire a highly reliable service that meet their quality and functional requirements.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.50
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• pp.27-59
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• 2011

This article attempts to describe and analyze the rules on the service provider's duty to provide his service in conformity with the contract under the Draft Common Frame of Reference (here-in-after DCFR), which are applied to construction, storage, design and factual information contracts. It categorizes such rules in accordance with the requirements of conformity with the contract, the time when the service provided must be in conformity with the contract, and the exemptions of the service provider's duty. On the basis of such categorization, it examines the rules on the service provider's duty in each type of service contract under the DCFR. By doing so, it seeks to figure out how the members of EU compromised on the various issues of the service provider's duty under the DCFR which is regarded as the first uniformed legislation in the area of the service contract. This may provide some guidance to the legislators of domestic law for their amendment or interpretation of their laws. In addition to them, this article also seeks to point out problems in terms of their interpretations and gaps in their rules to cover various aspects of non-conformity and put forward some solutions for such problems and gaps.

• Journal of Internet Computing and Services
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• v.17 no.4
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• pp.27-34
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• 2016

The referents of internet addresses are no longer limited to web sites. A new address service by the international organization for the internet address (ICANN) introduces an open space for the TLD (Top Level Domain) strings so that each service, content, product, and other linguistic expressions may be allowed. The open TLD addresses are more suitable for representing the address of service units, contents, or products. In this paper, as an alternative to static Internet address service to return a consistent mapping result regardless of a user-specific different requirements, we design a dynamic internet address mapping model that returns mapping result to suit user particular requirements. In addition, we propose a method for implementing a internet address service without any changes in the existing domain protocols. It may implement a dynamic internet address by attaching to a encoded user's metadata and environment data within a internet address representation, and adding the module for dynamic mapping to the name servers. Through this proposal, trying to expand the functions of internet address, it is expected to be able to provide customized informaiton retrieval services for each user by using just internet address.

• The KIPS Transactions:PartA
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• v.10A no.6
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• pp.651-656
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• 2003

Emerging technologies, such as multimedia and mobile computing, require that middleware platforms can support high adaptability in order to provide more flexible services in heterogeneous environments. To support high quality of service in distributed wired/wireless environments, it will be necessary for applications and middleware to be aware of changes in users requirements as well as environmental conditions, also to be able to adapt their behaviour as such changes. According to the needs of adaptability supporting in middleware, we structure a component-based, mobile agents framework in base level and meta level by using reflection. We propose concepts of meta agents and meta-service agents that are able to reflect changes made by mobile agents to the system. At the meta level of our framework, meta agents monitor execution of mobile agents and it is possible to provide dynamic adaptation of users requirements, deployment of application services and service customization with meta agents and meta-service agents.

• Journal of KIISE:Software and Applications
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• v.35 no.3
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• pp.137-148
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• 2008

Services system which has been emerging as a new way of application development utilizes services as fundamental units for developing a system. Services system can offer services within web environment as well as the ubiquitous environment where mobile devices are connected to wired or wireless network. In order to provide the functionality that meets users' requirements, the most appropriate service should be selected among candidate services by taking requests and context information into account. Therefore, it is important that the service system should provide services to users by dynamically adapting to users' requirements and context information. Since different users request same functionality with different context information, one service can be differently offered to users so that variability can happen to the service systems. Most researches on context-aware systems have a tendency to solve dynamic adaptation by using more or less ad hoc manner In this paper, we consider various types of services which are performed according to context information as variability and propose adaptable architecture by applying concepts of product line architecture in order to deal with variabilities systematically.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.11
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• pp.1288-1296
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• 2012

A candidate hybrid satellite and terrestrial network architecture, MSS/ATC(Mobile Satellite Service/Ancillary Terrestrial Component), is proposed for utilizing efficiently the exist MSS bands. Studies on the adjacent channel interference from the existing terrestrial mobile services and MSS/ATC itself are important to allocate a new ATC service frequency in MSS band. In this paper, we have analyzed the minimum permission power of terrestrial base station and the capacity loss with parameters of ACIR, number of MS(mobile Station) and MES(Mobile Earth Station) in uplink, and also, the capacity performance based on 1 beam and 1 cell assumption for MSS/ATC in downlink. The ACIR requirements are estimated in two MSS/ATC frequency allocation scenarios for 5 MHz and 10 MHz guard band to share spectrum with adjacent systems, and according to these ACIR requirements the service coverage and the receiver filter for ATC system should be designed in near future.