Yoonsun Lim

Bio: Yoonsun Lim is an academic researcher from Ewha Womans University. The author has contributed to research in topics: Component (UML) & Enterprise information security architecture. The author has an hindex of 3, co-authored 11 publications receiving 21 citations.

An e-learning framework supporting personalization and collaboration

Abstract: Advances in Internet technology have made possible, rapid adoption of e-learning in many fields of society. Various educational methods for e-learning have been developed because personalization can be easily implemented through web services. However, these e-learning methods are not widely used because it is difficult for instructors to apply them in developing their courseware. Currently, the most widely used style of e-learning courseware is viewing video clips of lectures and discussing the lecture using bulletin boards. It is an electronic version of the traditional classroom. In this paper, we propose a user-friendly e-learning framework that supports personalization and collaboration between the instructor and the students. Instructors can create various levels of learning objects and define the relationships between the objects. Students can select the topics of their interest and dynamically adjust the level of learning in real time. Multiple instructors can cooperate in expanding the courseware. All the participants can also annotate the learning materials independently.

A bitmap index for multidimensional data cubes

Abstract: Multidimensional arrays can be used to store multidimensional data cubes. One way of storing such array onto disk is to partition the array into a set of small chunks that can fit in a disk block. Chunks are usually of the same side length and are compressed before being stored, in order to achieve high query processing speed and space utilization. This scheme is called the chunk-based cube storage scheme. Although the scheme is considered to be a position based storage scheme, the chunks cannot be retrieved fast without using indexes since they are compressed. In this paper, we propose a bitmap index for such a storage scheme. The index can be constructed with the data cube in parallel. The relative positions of the chunks are retained in the index so that the chunk retrieval can be done in constant time. We placed in an index block as many chunks as possible so that the number of index searches is minimized for OLAP operations such as slice, dice, and range queries. We evaluated the proposed index by comparing it with existing multidimensional indexes such as UB-tree and grid file in terms of time and space.

A Bitmap Index for Multidimensional Data Cubes

Abstract: Multidimensional arrays can be used to store multidimensional data cubes. One way of storing such array onto disk is to partition the array into a set of small chunks that can fit in a disk block. Chunks are usually of the same side length and are compressed before being stored, in order to achieve high query processing speed and space utilization. This scheme is called the chunk-based cube storage scheme. Although the scheme is considered to be a position based storage scheme, the chunks cannot be retrieved fast without using indexes since they are compressed. In this paper, we propose a bitmap index for such a storage scheme. The index can be constructed with the data cube in parallel. The relative positions of the chunk retrieval can be done in constant time. We placed in an index block as many chunks as possible so that the number of index searches is minimized for OLAP operations such as slice, dice, and range queries. We evaluated the proposed index by comparing it with existing multidimensional indexes such as UB-tree and grid file in terms of time and space.

A Reuse-Based Software Development Method

Abstract: One of the primary obstacles to the reuse of independently-developed binary components on the industrial level lies in that the existing component technologies do not clearly separate component assembly from component development. To tackle this problem, we propose a new component model, a component assembly method, and a runtime framework, which together amounts to what we call Active Binding Technology. This new component model suggests how to make software components as pure parts, and the assembly method expresses message flows between these components in a model, while the runtime framework performs dependency injection to make the components interact with each other observing type safety constraints.

An Enterprise Security Management System as an ASP Solution

Abstract: Advances in Internet technologies have enabled not only large corporations but also small/medium businesses to utilize the Internet for their businesses. While enterprises can be more competitive with such high-tech tools, they are now inevitably exposed to various security risks and threats. In order to protect their information assets, large corporations purchase and operate enterprise security management systems which provide enterprise-level integrated security. However, they are so expensive that small/medium businesses can hardly afford to utilize one. We hold that one way of providing integrated security to small/medium businesses in a costeffective manner is by means of an ASP solution. In this paper, we justify our proposition by analyzing the market trends for ASP in conjunction with security management software. We also propose a web-based security management system that can be used as an ASP solution. To the best of our knowledge, it is the first such system and is currently running as a commercial solution at a Korean ASP which provides services to 3,000 small/medium businesses.

Personalized e-learning architecture in standard-based education

Abstract: Naturally every individual is unique. Thus, learning process in every learner is also different. On the other hand, education requires every learner to achieve a certain standard of competency. Standards are made to ensure all learners meet the defined learning outcome. In order to help learner achieve the targeted competency based on their own pace and way of learning, we propose personalized e-learning architecture that complies with standard. This study explores various theories and best practices of e-learning and confronted with various ways of learning due to cultural diversity in Indonesia. The analysis reveals components that commonly play important part in personalization: integrated learning structure, learner model, personalized learning scenario, personalized content selection, and portfolio-based assessment. These five components are interrelated to compose personalized e-learning system. The proposed architecture facilitates various ways of learning as well as aligns with expected learning outcome. A prototype system of the proposed architecture will be built in future to show the contribution.

Software Metrics to Estimate Software Quality using Software Component Reusability

Abstract: Today most of the applications developed using some existing libraries, codes, open sources etc. As a code is accessed in a program, it is represented as the software component. Such as in java beans and in .net ActiveX controls are the software components. These components are ready to use programming code or controls that excel the code development. A component based software system defines the concept of software reusability. While using these components the main question arise is whether to use such components is beneficial or not. In this proposed work we are trying to present the answer for the same question. In this work we are presenting a set of software matrix that will check the interconnection between the software component and the application. How strong this relation defines the software quality after using this software component. The overall metrics will return the final result in terms of the boundless of the component with application.

Designing personalisation in LAMS

Abstract: Recent advances in technology have facilitated the use of e-learning in education and made personalisation possible in various ways. These developments have been supported by the widespread availability of learning management systems (LMS). In educational establishments an LMS is often only used to support the enhancement of classroom or lecture-based teaching, however it is increasingly being used to provide e-learning only courses (Kim, Jung, Lim, Kim, Noh, 2009). Most learning management systems place considerable emphasis on delivering and managing learning content but generally add little or no value to the learning process and its personalisation(Junqi, Zhengbing, Zongkai, Yumei, 2009). In this paper, the authors will describe how personalisation is supported through a process of profiling individual learning styles using the Felder-Silverman framework and implemented through the Learning Activity Management System (LAMS).Whilst results are still to be analysed, the authors discuss the design of the subsequent learning system which will generate data and enable a comparison of students who followed a pathway based on the free-choice of learning materials with students who followed a pathway that incorporating structured ‘personalised’ learning materials based on the learners’ predetermined learning style.

An Adoption Model for E-Learning and Knowledge Management Systems

Abstract: The authors built an electronic learning EL and knowledge management KM adoption model for sharing, updating, and adopting the essences of EL and KM based on the existing literature, as well as data and information from face-to-face interviews of 17 EL and KM researchers worldwide. In this paper, the authors discuss the theoretical and practical implications of the model and offer some suggestions for practical improvement of EL and KM systems. The authors used qualitative research and inductive reasoning approaches for this study. Findings show that the proposed model directly impacts EL and KM academics, as well as practitioners, through the adoption of EL and KM systems, and Knowledge Science is enriched by nurturing new concepts and facilitating more opportunities to enhance collaborative, innovative, open, and distributed knowledge sharing and knowledge-adopting culture.

Evaluation of Avatar and Voice Transform in Programming E-Learning Lectures

Abstract: This article reports the effectiveness of high frame rate facial animated avatar and voice transformer in eLearning. Three avatars: (Real male professor, Male avatar, Female avatar) were combined with male professor's voice or VT-4 vocoder transformed voice to create 6 distinguished videos which were then viewed university freshmen students. A total of 186 students divided into 15 groups participated in this experiment. Female avatar was the most appealing avatar visually, but its combination with voice transform severely hinders its overall score. This research can be extended to real time live with with preferences of students and draw more connections between student perception of avatar and actual lecturers.