• Journal of KIISE:Software and Applications
• /
• v.37 no.7
• /
• pp.518-535
• /
• 2010

Cloud Computing is emerged as an effective reuse paradigm, where service providers operate hardware and software and as a service, and service consumers invoke the service through Internet. Software-as-a-Service (SaaS) is a type of cloud services, where the whole software is designed as a service so that several consumers can reuse the SaaS. While tradition software applications are developed for a specific organization, SaaS is developed for multiple users in the various organizations. Hence, reusability is very essential characteristic of SaaS. Reusability is defined as a metric of how effective and efficient software functionalities can be used by various users. Reusability in SaaS is evaluated by considering three sub-characteristics; applicability, adaptability, and scalability. Since such a SaaS has considerable differences and characteristics from traditional software applications, conventional methods including object-oriented modeling, component-based development method, and service-oriented architecture (SOA) service development method would be limited in developing services which can fulfill these three sub-characteristics related to reusability as well as SaaS-intrinsic characteristics. Hence, there is a great demand for effective processes for developing SaaS cloud services. In this paper, we present a practical process for developing SaaS, which focuses on ensuring reusability. And by performing a case study with our proposed SaaS development process, we evaluate applicability of our proposed process and explain how the process is used in a real domain. Then, we compare our proposed process with others for verifying our study. Through the proposed process, cloud services with high quality can be more effectively developed.

• Journal of Internet Computing and Services
• /
• v.9 no.3
• /
• pp.119-128
• /
• 2008

To use commercial software, most software users purchase the software. Some software users, who do not use the software frequently, regard purchasing the software as undue expense. Software rental service can be an effective substitute. To support the software rental service, charging scheme is necessary. Two categories of charging scheme can be considered. One is charging a fixed amount of fee for a fixed period of time and the other is charging a fee based on the actual usage time. In this paper, the software pay-per-use approach based on the amount of time that the software user has used is proposed. The proposed approach gives the capability to calculate the usage time.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.11 no.9
• /
• pp.4398-4417
• /
• 2017

Multi-user Multiple-Input and Multiple-Output (MU-MIMO) has potential for prominently enhancing the capacity of wireless network by simultaneously transmitting to multiple users. User selection is an unavoidable problem which bottlenecks the gain of MU-MIMO to a great extent. Major state-of-the-art works are focusing on improving network throughput by using Channel State Information (CSI), however, the overhead of CSI feedback becomes unacceptable when the number of users is large. Some work does well in balancing tradeoff between complexity and achievable throughput but is lack of consideration of fairness. Current works universally ignore the rational utilizing of time resources, which may lead the improvements of network throughput to a standstill. In this paper, we propose TOUSE, a scalable and fair user selection scheme for MU-MIMO. The core design is dynamic-time-warping-based user selection mechanism for downlink MU-MIMO, which could make full use of concurrent transmitting time. TOUSE also presents a novel data-rate estimation method without any CSI feedback, providing supports for user selections. Simulation result shows that TOUSE significantly outperforms traditional contention-based user selection schemes in both throughput and fairness in an indoor condition.

• Journal of Korean Institute of Industrial Engineers
• /
• v.33 no.4
• /
• pp.487-493
• /
• 2007

In this paper, we deal with an optimal software-release problem of determining the time to stop testing and release the software system to the user. The optimal release time problem is considered from maintenance like the periodic distribution of service packs and the unpredictable distribution of patches after the release. Moreover, the environment of software error-detection during operation differs from the environment during testing. This paper proposes the software reliability growth model which incorporates periodic service packs, unpredictable patches and operational environment. Based on the proposed model, we derive optimal release time to minimize total cost composed of fixing an error, testing and maintenance. Using numerical examples, optimal release time is determined and illustrated.

• Journal of The Korean Association of Information Education
• /
• v.23 no.3
• /
• pp.245-254
• /
• 2019

In the 2015 revision curriculum, software education must be conducted for 17 hours in elementary school fifth or sixth grade. Pre_service elementary teachers should be able to teach software. In this study, learning factors according to the achievement criteria for software education will be defined for pre-service elementary teachers. Pre-service teachers were taught by learning elements. As a result, the pre_service teachers were able to create teaching and evaluation materials for each learning element. It was also found that the pre-service teachers improved their ability to teach software education in elementary school based on these materials.

• The Journal of Korea Robotics Society
• /
• v.5 no.2
• /
• pp.169-176
• /
• 2010

Robotic software has been dramatically complicated as performing intelligent service tasks. These types of robots demand a very powerful software framework to make them easy. Robotic software framework means an integrated software environment that simplifies jobs of robotic software engineer by providing tools, reusable components, and runtime environments. Finally it reduces the project cost. There are lots of works related with them. Among them we focus on five frameworks that are MSRDS, ERSP, OROCOS, OpenRTM, and OPRoS. In terms of intelligent service robot, the study on robotic software frameworks is very important. And outlook on them is also very important in the sense of that the robotic software frameworks should be used to initiate service robot market.

• Journal of Digital Contents Society
• /
• v.11 no.4
• /
• pp.537-543
• /
• 2010

According to software growth, also software maintenance has been continuously improving. In addition, the existing concept of correct maintenance demands operational management and improvement of service. However, we have various limitation matters to reflect the requirements of service base for maintenance accomplishment. Therefore, we need the study of the service based process for solving such a problem. In this paper, we propose a Service based Software Maintenance Process. Proposed process based on ISO12207 standard for software development and maintenance and compares it with the service based representative standards. In a related works, we study activity of $SM^{MM}$, ITSCMM, ITIL and find out activities to be concerned with and compare it with activity of ISO 12207 and distinguish the maintenance process activity of the service base from maintenance activities. And then, we propose a service management stage. It define four activities and eight artifacts. Finally, we validate the result by comparing the proposed process with a general service operational process.

• Journal of Information Technology Services
• /
• v.5 no.2
• /
• pp.137-153
• /
• 2006

SOA(Service Oriented Architecture) can be a technique to make compassable software from mapping business service to software component. To support effective SOA, it is important that services have to be defined or classified more independently for dynamic and reusable composition. Several methods have been issued but no ways to defined service granularities, service type or service unit. In this paper we introduce 3 level views, service level, service granularity to reuse effectively. And, we suggest service definition guidelines using them.

• The Journal of Korea Robotics Society
• /
• v.5 no.3
• /
• pp.240-250
• /
• 2010

A URC, which is a Ubiquitous Robot Companion, provides services to users in ubiquitous computing environments and has advantage of simplifying robot's hardware and software by distributing the complicated functionality of robots to other system. In this paper, we propose SOWL, which is a software architecture for URC robots and a mixed word of SOMAR and CAWL. SOWL keeps the advantages of URC and it also has the loosely-coupled characteristics. Moreover it makes it easy to develop of URC robot software. The proposed architecture is composed of 4 layers: device software, robot software, robot application, and end user layer. Developers of the each layer is able to build software suitable for their requirements by combining software modules in the lower layer. SOWL consists of SOMAR and CAWL engine. SOMAR, which is a middleware for the execution of device software and robot software, is based on service-oriented architecture(SOA) for robot software. CAWL engine is a system to process CAWL which is a context-aware workflow language. SOWL is able to provide a layered architecture for the execution of a robot software. It also makes it possible for developers of the each layer to build module-based robot software.

• The Journal of the Korea Contents Association
• /
• v.9 no.3
• /
• pp.81-90
• /
• 2009

Service oriented architecture software quality estimation is using Service oriented architecture techniques by method can improve objectivity and practical use degree through strategy technology development that accommodate international standard as technology that can motive quality sophistication and many software corporations embody business requirement and solution to associate. Also, setting an example business of government dimension is propeled and common use anger of Service oriented architecture base software according to technical development of related business circles is spreading. Therefore, proposed examination Metrik and measure quality and achieve research about method to decide the result according to suitable standard and present estimation example and present definitely estimation method to estimate Maintainability quality of Service oriented architecture base software in this research. Motive Maintainability quality sophistication of Service oriented architecture base software through this research and about Service oriented architecture base software quantitative / that can fulfill qualitative demand see.