• Journal of Communications and Networks
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• v.16 no.2
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• pp.238-244
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• 2014

A key technical challenge in TV white spaces is the efficient spectrum usage without interfering with primary users. This paper considers available spectrum discovery scheme using in-band sensing signal to support super Wi-Fi services effectively. The proposed scheme in this paper adopts non-contiguous orthogonal frequency-division multiplexing (NC-OFDM) to utilize the fragmented channel in TV white space due to microphones while this channel cannot be used in IEEE 802.11af. The proposed solution is a novel available spectrum discovery scheme by exploiting the advantages of a sensing signaling. The proposed method achieves considerable improvement in throughput and delay time. The proposed method can use more subcarriers for transmission by applying NC-OFDM in contrast with the conventional IEEE 802.11af standard. Moreover, the increased number of wireless microphones (WMs) hardly affects the throughput of the proposed method because our proposal only excludes some subcarriers used by WMs. Additionally, the proposed method can cut discovery time down to under 10 ms because it can find available channels in real time by exchanging sensing signal without interference to the WM.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2003.10a
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• pp.133-138
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• 2003

The prediction of protein secondary structure has been an important bioinformatics tool that is an essential component of the template-based protein tertiary structure prediction process. It has been known that the predicted secondary structure information improves both the fold recognition performance and the alignment accuracy. In this paper, we describe several novel ideas that may improve the prediction accuracy. The main idea is motivated by an observation that the protein's structural information, especially when it is combined with the evolutionary information, significantly improves the accuracy of the predicted tertiary structure. From the non-redundant set of protein structures, we derive the 'potential' parameters for the protein secondary structure prediction that contains the structural information of proteins, by following the procedure similar to the way to derive the directional information table of GOR method. Those potential parameters are combined with the frequency matrices obtained by running PSI-BLAST to construct the feature vectors that are used to train the support vector machines (SVM) to build the secondary structure classifiers. Moreover, the problem of huge model file size, which is one of the known shortcomings of SVM, is partially overcome by reducing the size of training data by filtering out the redundancy not only at the protein level but also at the feature vector level. A preliminary result measured by the average three-state prediction accuracy is encouraging.

• Korean Institute of Interior Design Journal
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• v.13 no.1
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• pp.62-69
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• 2004

The purpose of this study was to analyze spatial composition of elderly skilled nursing facility and to provide basic information for setting up the detail facility architectural guidelines. The results of the study were following: the residential spaces of the facilities in this study were more or less overcrowded since their capacity were more than 5 elderly residents. The dimensions of some residential spaces did not even come up to the standard of elderly welfare law in force. On the other hand, the facilities had a tendency to use a space with multiple purposes or to allocate a space but to leave it with no use. Moreover comparing with the 1st floor, which was mainly for the staffs and had enough space to spare, the upper floor which was for the elderly residents, was crowded with nursing staffs and elderly residents and had densely closed residential and public spaces. For the problem solving, law and regulation modification is needed according to the case study about the usage and using frequency of each facility space. And the crowded area for the elderly residents could be enlarged through the reduction(or combination) of the rarely used spaces and moving a few residential spaces into the 1st floor.

• Journal of Korean Institute of Industrial Engineers
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• v.21 no.1
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• pp.119-135
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• 1995

We consider problems of tool loading and scheduling in a flexible manufacturing system (FMS) in which tool transportation constitutes the major portion of material flows. In this type of FMSs, parts are initially assigned to machines and released to the machines according to input sequencing rules. Operations for the parts released to the machines are performed by tools initially loaded onto the machines or provided by an automatic tool transport robot when needed. For an efficient operation of such systems, therefore, we may have to consider loading and scheduling problems for tools in addition to those for parts. In this paper, we consider three problems, part loading, tool loading, and tool scheduling problems with the overall objective of minimizing the makespan. The part loading problem is solved by a method similar to that for the bin packing problem and then a heuristic based on the frequency of tool usage is applied for tool loading. Also suggested are part input sequencing and tool scheduling rules. To show the effectiveness of the overall algorithm suggested here, we compare it with an existing algorithm through a series of computational tests on randomly generated test problems.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.4
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• pp.275-281
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• 2014

This study has been analyzed the sound performance of the noise barriers with respect to the configuration of the front perforated panel geometries and the filled absorption materials. Noise barriers' acoustic performance should be required to meet 0.7 of NRC value at least. The global absorbing performance of the barriers have been investigated by changing the opening ratio of the front perforated panel and the absorbing characteristics of the absorbing material using two microphone method. Therefore, It it possible to obtain to increase acoustic performance of the specific frequency ranges by designing the perforate rates of the front panel and absorbing characteristics of the absorbing materials inside, as well. This study try to find out the possibilities of applying the absorbing noise barrier to railway usage.

• Journal of Educational Research in Mathematics
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• v.25 no.3
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• pp.407-429
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• 2015

This study aims to find the elementary mathematics teachers' satisfaction, availability, and needs, based on the mathematics teaching models in current mathematics curriculum. The satisfaction on current mathematics teaching models is about 80%, but the frequency of usage of the models is a bit low because the models are used once a unit or a semester. Among other subjects, the teachers prefer the teaching models of social studies or science, because the models are convenient in applying models to their teaching. We proposed a few ideas to enhance the availability of mathematics teaching models including the consideration on a variety of content areas of mathematics, students' differences of their mathematics levels, and the teaching and learning methods in mathematics curriculum.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.5
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• pp.990-992
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• 2007

The purpose of this study is to develop a practical gait-event detection system which is necessary for the FES (functional electrical stimulation) control of locomotion in paralyzed patients. The system is comprised of a sensor board and an event recognition algorithm. We focused on the practicality improvement of the system through 1) using accelerometer to get the angle of shank and dispensing with the foot-switches having limitation in indoor or barefoot usage and 2) using a rule-base instead of threshold to determine the heel-off/heel-strike events corresponding the stimulation on/off timing. The sensor signals are transmitted through RF communication and gait-events was detected using the peaks in shank angle. The system could detect two critical gait-events in all five paralyzed patients. The standard deviation of the gait events time from the peaks were smaller when 1.5Hz cutoff frequency was used in the derivation of the shank angle from the acceleration signals.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.226-230
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• 2007

This paper proposes a local scheduling method based on user pattern for Volunteer computing project, Korea@Home. It enables Korea@Home participants to run the agent without disturbance. It is devised to prevent user's application from delay while running the agent and decreases the frequency of switching resource between the user and the agent. We analyze the user's patterns of donating computing resource with Korea@Home which is a representative volunteer computing project in Korea. It has contributed the computing power to several applications including climate prediction and virtual screening. It promotes the volunteers to participate continuously without disturbance and increases the potential computing power with non-disturbance scheduling based on user usage pattern for Volunteer Computing.

• Journal of Distribution Science
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• v.18 no.1
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• pp.27-34
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• 2020

Purpose : In the aviation industry, we will investigate the impact of users' acceptance of technology on their usage behavior and find out the factors that affect their acceptance of technology. We will expand the prior study to find out the impact of the self-service technology of Incheon Airport. Research design, data and methodology : Within the last six months, the survey was conducted on people using self-service technology at Incheon International Airport from July to August 2019. Part 307 of the valid questionnaires were used for this final analysis. The collected data were used to perform frequency, factor, reliability, and multiple regression analyses using the SPSS statistical package. Results : Individual aspects of external variables, service aspects and system aspects have been shown to affect usefulness and perceived ease of use. Also, perceived ease-of-use and usefulness have effects on users' intention to accept technology. Conclusions : The perceived easement and perceived usefulness of Incheon International Airport has been shown to affect self-service users. Increasing the user's self-efficiency and increasing the user's expectations for benefits, convenience, rapid processing, and minimal effort will have a positive meaningful effect on the intention of accepting the technology.

• Journal of KIISE:Software and Applications
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• v.33 no.5
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• pp.470-480
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• 2006

The longer the input sentences, the worse the parsing results. To improve the parsing performance, many methods about long sentence segmentation have been reserarched. As an isolating language, Chinese sentence has fewer cues for sentence segmentation. However, the average frequency of comma usage in Chinese is higher than that of other languages. The syntactic information that the comma conveys can play an important role in long sentence segmentation of Chinese languages. This paper proposes a method for classifying commas in Chinese sentences according to the context where the comma occurs. Then, sentences are segmented using the classification result. The experimental results show that the accuracy of the comma classification reaches 87.1%, and with our segmentation model, the dependency parsing accuracy of our parser is improved by 5.6%.