• Journal of KIISE:Software and Applications
• /
• v.30 no.3_4
• /
• pp.231-238
• /
• 2003

This paper presents a virtual grouping method used in multi-user network games, which reduces a response time and losses of response data. The proposed method divides each group into virtual groups and transmits data in them after dividing an overall map on a game into several fixed regions and grouping them. And this paper derives the optimal number of groups minimizing a given cost function. The proposed method if shown to be useful by comparing with a general grouping method.

• Journal of Multimedia Information System
• /
• v.6 no.4
• /
• pp.179-184
• /
• 2019

This paper introduces a study for procedurally generating the behavior of objects in a virtual environment at runtime. This study was initiated to enable the behavioral model of objects in virtual reality applications to evolve in response to user behavior at runtime. Our approach is to describe the behavior of an object as a behavior tree, and to make a node of the behavior tree change to another type if a certain condition is satisfied. We defined four types of node changes: "parameterized", "probabilistic", "alternate", and "variant". We experimented with a virtual environment that includes a variety of simple procedural elements to explore the possibilities of our approach. As a result of the implementation, if an optimization algorithm that can select and apply the optimized procedural elements in response to the user's behavior is complemented, it is confirmed that more intelligent objects and agents can be implemented in virtual reality applications.

• Journal of Korean Institute of Industrial Engineers
• /
• v.32 no.2
• /
• pp.82-90
• /
• 2006

Reconfigurability of machine tools is one of the critical factors to realize the responsive manufacturing systems to satisfy the mass customization production. This paper presents the methods to model the reconfigurable machine tools (RMTs) on Internet in response to change in the machining requirements. Specifically, the structure and motion model of machine tools using module combination rules and connectivity graph are developed. And we developed Internet-based simulator for designing of RMTs (ISD-RMT). In response to the user requirements, various structures of RMTs can be derived using the module combination rules and connectivity graph relationships. In addition, the user can verify generating structures through the control and simulation procedures.

• Proceedings of the Korea Inteligent Information System Society Conference
• /
• 2003.05a
• /
• pp.400-409
• /
• 2003

Collaborative filtering (CF) recommendation is a knowledge sharing technology for distribution of opinions and facilitating contacts in network society between people with similar interests. The main concerns of the CF algorithm are about prediction accuracy, speed of response time, problem of data sparsity, and scalability. In general, the efforts of improving prediction algorithms and lessening response time are decoupled. We propose a three-step CF recommendation model which is composed of profiling, inferring, and predicting steps while considering prediction accuracy and computing speed simultaneously. This model combines a CF algorithm with two machine learning processes, SOM (Self-Organizing Map) and CBR (Case Based Reasoning) by changing an unsupervised clustering problem into a supervised user preference reasoning problem, which is a novel approach for the CF recommendation field. This paper demonstrates the utility of the CF recommendation based on SOM cluster-indexing CBR with validation against control algorithms through an open dataset of user preference.

• Journal of the Architectural Institute of Korea Structure & Construction
• /
• v.34 no.3
• /
• pp.95-102
• /
• 2018

In order to understand interaction between building users' occupant performance and building maintenance performance of maintenance management personnel, actual data from maintenance activities of buildings were analyzed. Also, using building defect customer complaint data reported by building user, satisfaction data on building maintenance services of building users and service response time of maintenance management personnel, a method for evaluating interaction of buildings with the same purpose and same size was proposed. Throughout analysis, average number of occurrences per unit area per year for the mechanical complaints in complex building were presented. In addition, using building users' satisfaction with facility management services, attitude of responding to business obstacles, number of occurrences per unit area per year of mechanical complaints and complaint processing speed, interaction was comprehensively identified and compared.

• Korean Institute of Interior Design Journal
• /
• v.20 no.6
• /
• pp.350-358
• /
• 2011

In contemporary architecture, Environment is not just a non-objective space. It is an experimental space where physical space and the principal result of interaction and order have been granted in symbolic, introverted space. Therefore, Yokohama International Port Terminal characteristics that appear in the architectural space, the nature of human desires and reveal the value of user-centered criteria to classify the type of response characteristics of the affordance are as follows; First, the experience response in the affordance reaction is when users reaction is multiple in theenvironment. Second, the evolution of organic reactions in a public space system is that it shows the spatial characteristics of the functional relationships. Third, the organic of space that can be seen through cultural practice in the inside and outside of the space could be explained as a perceptual response. It can be an opportunity to analyzed and develop in a various forms of space in environmental design if we understands the spatial characteristics of FOA's Yokohama International Port Terminal and applied end user spatial reaction analysis that shows an affordance relationship study.

• KIPS Transactions on Computer and Communication Systems
• /
• v.2 no.6
• /
• pp.231-236
• /
• 2013

Recently, to improve the user response times of Android applications, several studies have been proposed to combine the idea of Ahead-of-Time compilation into Dalvik virtual machine, which uses Just-in-Time compilation. The studies, however, require modifications of the Dalvik executables of target applications, thus are difficult to be adopted for legacy applications already deployed. This paper proposes a JITwP(JIT with Precompile) technique that precompiles hot traces at application launch time with no modification of the Dalvik executable. It improves the user response times of target applications by providing precompile hints prepared offline. Our experimental results demonstrate a 4% improvement in terms of execution time for the Web browser application.

• Journal of KIISE:Computer Systems and Theory
• /
• v.36 no.2
• /
• pp.94-101
• /
• 2009

We introduce a user authentication system using distance estimation and a simple challenge response protocol based on a pre-established key. Using the time difference of arrival between an RF signal and an ultrasonic signal, an authenticator verifies if a user's authentication token is within its threshold distance, and it also verifies if the token's response to its random challenge is valid. We implement our authentication system and we analyze the success rates for authentication according to the variations in the distances and facing angles between the authenticator and the token. Our experimental results show that the token is authenticated with very high probability in reasonable settings.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.16 no.1
• /
• pp.97-115
• /
• 2022

Smart power grid is a user friendly system that transforms the traditional electric grid to the one that operates in a co-operative and reliable manner. Demand Response (DR) is one of the important components of the smart grid. The DR programs enable the end user participation by which they can communicate with the electricity service provider and shape their daily energy consumption patterns and reduce their consumption costs. The increasing demands of electricity owing to growing population stresses the need for optimal usage of electricity and also to look out alternative and cheap renewable sources of electricity. The solar and wind energy are the promising sources of alternative energy at present because of renewable nature and low cost implementation. The proposed work models a smart home with renewable energy units. The random nature of the renewable sources like wind and solar energy brings an uncertainty to the model developed. A stochastic dual descent optimization method is used to bring optimality to the developed model. The proposed work is validated using the simulation results. From the results it is concluded that proposed work brings a balanced usage of the grid power and the renewable energy units. The work also optimizes the daily consumption pattern thereby reducing the consumption cost for the end users of electricity.

• International Journal of Contents
• /
• v.11 no.1
• /
• pp.15-20
• /
• 2015

The purpose of this research is to study methods for performing transition that have visual representation of corresponding animations with no bounce in subsequently recognized user information when attempting to interact with a virtual 3D character in real-time using user motion. If the transitions of the animation are needed owing to a variety of external environments, continuous recognition of user information is required to correspond to the motion. The proposed method includes linear interpolation of the transition using cross-fades and blending techniques. The normalized playing time of the source animation was utilized for automatically calculating the transition interpolation length of the target animation and also as the criteria in selecting the crossfades and blending techniques. In particular, in the case of blending, the weighting value based on the degree of similarity between two animations is used as a blending parameter. Accordingly, transitions for visually excellent animation are performed on interactive holographic projection systems.