• Journal of the Korean Institute of Educational Facilities
• /
• v.17 no.2
• /
• pp.3-12
• /
• 2010

The purpose of this study was to provide the planning guideline for the multi-purposed classroom in the elementary school and middle school using questionnaire and user participation method. As the user participation method, the design workshop in the study contains participation techniques, community action planning, and participation game. The design workshop used the design kit as a communication tool. Four user groups, selected from teachers and child in the elementary school and middle school, to be reconstructed, participated in a design workshop with design kit, and each group produced their own plans. The result of this study is as follows; (1) Teachers wanted multi-purposed classroom to be used by two classes. (2) The size of the multi-purposed classroom was preferred 1.5 times(30 py.) of the regular classroom. (3) By considering the characteristics of students it was required the open space in elementary, but required it to be separated from the regular classroom in middle school. (4) Through the analysis, we could grasp the processes that the users' needs were practically applied to design. Our design workshop method should be hereafter modified and advanced, but showed the usefulness in many aspects.

• Journal of Information Processing Systems
• /
• v.17 no.4
• /
• pp.707-720
• /
• 2021

To improve the accuracy of the recommendation system, multi-criteria recommendation systems have been widely researched. However, it is highly complicated to extract the preferred features of users and items from the data. To this end, subjective indicators, which indicate a user's priorities for personalized recommendations, should be derived. In this study, we propose a method for generating recommendation candidates by predicting multi-criteria ratings from reviews and using them to derive user priorities. Using a deep learning model based on convolutional neural network (CNN) and bidirectional long short-term memory (BiLSTM), multi-criteria prediction ratings were derived from reviews. These ratings were then aggregated to form a linear regression model to predict the overall rating. This model not only predicts the overall rating but also uses the training weights from the layers of the model as the user's priority. Based on this, a new score matrix for recommendation is derived by calculating the similarity between the user and the item according to the criteria, and an item suitable for the user is proposed. The experiment was conducted by collecting the actual "TripAdvisor" dataset. For performance evaluation, the proposed method was compared with a general recommendation system based on singular value decomposition. The results of the experiments demonstrate the high performance of the proposed method.

• Proceedings of the KIEE Conference
• /
• 2004.11c
• /
• pp.240-242
• /
• 2004

A channel allocation algorithm of multi-user OFDM(orthogonal frequency division multiplexing) system is presented. The proposed algorithm is to reduce the complexity of the system, using the GNN(gradual neural network) with gradual expansion scheme and the algorithm attempts to allocate channel with good channel gain to each user. The method has lower computational complexity and less iteration than other algorithms.

• Proceedings of the IEEK Conference
• /
• 2001.06a
• /
• pp.101-104
• /
• 2001

In TD-CDMA system, multi-user interference degrades the system performance. In this paper, we propose a effective multi-user detection algorithm applicable to TDD mode. We certify a channel estimation capacity by using midamble and performance of the proposed multistage interference canceller in the system complex aspect. In computer simulations, it is verified that proposed algorithm has lower complexity and better performance than conventional multi-user interference cancellation in Rayleigh fading channel.

• Proceedings of the KIEE Conference
• /
• 2007.04a
• /
• pp.237-239
• /
• 2007

In the paper, we analyze the performances of random access channels in multi-service multi-user OFDMA systems. The resource of the random access channels in OFDMA systems is the nubmer of available sub-channels and PN-codes. For given available sub-channels and PN-codes. we analyze the performances of the random access channels of OFDMA systems according to three resource allocation methods (resource full sharing, resource partial sharing, resource partition) in tenus of the access success probability, the blocking probability, the access delay and the throughput of each service class. Further, we find the feasible region of the access probability of each service class in which the allowable minimum access success probability, the allowable maximum blocking probability and the allowable maximum access delay are satisfied. The results also can be utilized to find proper region of the access probabilities of each service class for differentiated quality of service(QoS)s, and for the system operations.

• Journal of Industrial Technology
• /
• v.27 no.A
• /
• pp.141-147
• /
• 2007

In this paper, we define the multi-states exponential cell resident time mobility model for describing the mobility characteristics of mobile user and analyzed the total cost of the hybrid method using multi-states cell resident time. Generally, the mobile user has three states for its movement, such as staying, walking and driving. This multi-states cell resident time based hybrid method reflects the movement characteristics of mobile user and adapts the location update period according to the states of mobility speed. As a results of the performance analysis, we can get the optimum parameters of the hybrid method for multi-states based mobile users.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.10 no.7
• /
• pp.2972-2991
• /
• 2016

WLAN is the best choice in the place where complex network is hard to set up. Intelligent terminals are more and more assembled in some areas now. However, according to IEEE 802.11n/802.11ac, the access-point (AP) can only serve one user at a single frequency channel. The spectrum efficiency urgently needs to be improved. In theory, AP with multi-antenna can serve multiple users if these users do not interfere with each other. In this paper, we propose a user clustering scheme that could achieve multi-user selection through the mutual cooperation among users. We focus on two points, one is to achieve multi-user communication with multiple antennas technique at a single frequency channel, and the other one is to use a way of distributed users' collaboration to determine the multi-user selection for user clustering. Firstly, we use the CSMA/CA protocol to select the first user, and then we set this user as a source node using users' cooperation to search other proper users. With the help of the users' broadcast cooperation, we can search and select other appropriate user (while the number of access users is limited by the number of antennas in AP) to access AP with the first user simultaneously. In the network node searching, we propose a maximum degree energy routing searching algorithm, which uses the shortest time and traverses as many users as possible. We carried out the necessary analysis and simulation to prove the feasibility of the scheme. We hope this work may provide a new idea for the solution of the multiple access problem.

• Journal of the Ergonomics Society of Korea
• /
• v.15 no.1
• /
• pp.1-14
• /
• 1996

Menu-driven interfaces are frequently employed for user interfaces on many electronic products. Due to space constraint, a single or multi-line display is popularly used to show menu items unlike the software interfaces. Single or multi-line display present 8 .approx. 21. characters on an LCD screen and the user selects items using a series of button pushes. Multi-line displays are different from the single-line ones in the following aspects. First, they can present multiple line of information at the same time. Second, they can present menu items in a various way compared to single-line ones. However, due to their space constraint multi-line displays have many limitations compared to ordinary displays which usually use 14" screens. Therefore, guidelines are necessary for designing efficent multi-line display menus interfaces. In this study, a human factors experiment was conducted to examine the effects of three design variables which might affect the usability of a multi-line display menus. Factors investigated include menu structure, number of lines on the display, and item presentation method. Usability of the multi-line display menus was measured quantitatively in terms of four different aspects: speed, accuracy, inefficiency and preference. The analysis of variance was used not only to analyze the main effects of the factors and their interactions but also to see the differences between the single-line display menus and multi-line display ones. A set of design guidelines drawn from this study can be applied to the design of the user interfaces of a various types of electronic consumer products.

• 한국HCI학회:학술대회논문집
• /
• 2008.02a
• /
• pp.319-325
• /
• 2008

In this paper, we develop the multi sensor system, to get the sufficient information of mobile robot's environment. Mobile robot user interface, based on multi sensor system, can choice a suitable sensor by low-cost multi sensors and then acquisition information from remote robot's workspace using auto sequencing user display function. This research of multi sensor system is consists of ultrasonic sensor, position sensing detector, and low-cost CMOS camera module.

• Journal of the Korea Society of Computer and Information
• /
• v.12 no.1 s.45
• /
• pp.145-154
• /
• 2007

In this paper, an improved detection method is proposed by supplementing various types of Multi-Path gam for a MMSE Multi-User detecter. This method is proposed to complement the shortcomings of the conventional detection method which is used for multiuser detection in STBC(Space-Time Block Code) CDMA system. We analyzed the improved method in bit error probability viewpoint and compared the result with that of the conventional method. In this result, we showed that the improved method obtains better performance of bit error probability than the conventional method when parameters such as delay, number of user and SNR are changed.