• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.159-162
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• 2005

Random Early Detection (RED), one of the most well-known Active Queue Management (AQM), has been designed to substitute Tail Drop and is nowadays widely implemented in commercially available routers. RED algorithm provides high throughput and low delay as well as a solution of global synchronization. However RED is sensitive to parameters setting, so the performance of RED, significantly depends on the fixed parameters. To solve this problem, the Adaptive RED (ARED) algorithm is suggested by S. Floyd. But, ARED also uses fixed parameters like target-queue length; it is hard to respond to bursty traffic actively. In this paper, we proposed AQM algorithm based on the variation of current queue length in order to improve adaptability about burst traffic. We measured performance of proposed algorithm through a throughput, marking-drop rate and bias phenomenon. In experimentation, we raised a packet throughput as reduced packet drop rate, and we confirmed to reduce a bias phenomenon about bursty traffic.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.3
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• pp.265-275
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• 2000

By using thermal desorption/gas chromatograph/flame ionization detector(TD/GC/FID), this study was carried out to evalute an accuracy and a precision on Benzene(B), Toluene(T), o-Xylene(X) analysis in an industrial hygiene laboratory. Limits of detection of TD/GC/FID on B, T, X were showed 13.75ng/sample or less. For the accuracy of the method by concentration levels, overall bias was showed 7.7% as an absolute value, and the pooled coefficient of variation showed 3.51%. For the precision on repeatability of peak area and retention time between within-run and between-run of analytical system, it is showed the results of within-run gave better than those of between-run. Also the accuracy by sorbents(Tenax TA and Chromosorb 106)was evaluated, and the precision on reproducibility between MDHS72 and this study was compared. It is showed it is possible for TD/GC/FID to evaluate accurately B, T, X concentration levels of less than 1ppm at indoor or outdoor of workplaces in Korea.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.699-702
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• 2002

A DC current sensor is disclosed in which two pairs of saturable cores are provided so as enclose a conductor carrying a direct current to be measured. On each of the saturable cores, a bias winding, a feedback winding and an output winding are wound. Circuit for detection of an asymmetry in the magnetization current, generated by a reference alternating voltage, in a signal-conditioner. The reference alternating voltage is fed to the respective series circuits such that no resultant induction current is induced in the modulating current. The voltages over the resistor form input signals for two peak value detectors, the strength of the output signal of which represents the degree of asymmetry of magnetization current. This paper describes the development a DC current sensor and its signal-conditioner.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.2
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• pp.343-348
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• 2007

The physical properties of DMPC monolayer were made for dielectric relaxation phenomena by the detection of the surface pressures and displacements current. Lipid thin films were deposited by accumulation and the current was measured after the electric bias across the manufactured MIM device. It is found that the phospolipid monolayer of dielectric relaxation takes a little time and depend on the molecular area. When electric bias is applied across the manufactured MIM device by the deposition condition of phospolipid mono-layer, it wasn't breakdown when the higher electric field to impress by increase of deposition layers.

• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.12-13
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• 2006

The physical properties of DMPC monolayer were made for dielectric relaxation phenomena by the detection of the surface pressures and displacements current. The current was measured after the electric bias across the manufactured MIM device. It is found that the phospolipid monolayer of dielectric relaxation takes a little time and depend on the molecular area. When electric bias is applied across the manufactured MIM device by the deposition condition of phospolipid mono-layer, it wasn't breakdown when the higher electric field to impress by increase of deposition layers.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.64.2-64
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• 2001

In this paper, fabricated is a motion capture and attitude detection system for Head Mounted Display HMD composed of three low-price and low-grade micro gyroscopes and a micro-controller, To calculate attitude of a body, modified INS algorithm is used. Because the micro gyroscope has much bias drift error, scale factor error, and run-to-run bias error, the motion of a body can not be measured exactly if the general INS algorithm and micro gyroscopes are used. To reduce the errors, three accelerometers can be used. In this case, however, the size and power consumption become too large to use in HMD system. The modified INS algorithm use the grid map and the characteristics of the human motions.

• Smart Structures and Systems
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• v.29 no.1
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• pp.63-75
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• 2022

The raw data collected by structural health monitoring (SHM) systems may suffer multiple patterns of anomalies, which pose a significant barrier for an automatic and accurate structural condition assessment. Therefore, the detection and classification of these anomalies is an essential pre-processing step for SHM systems. However, the heterogeneous data patterns, scarce anomalous samples and severe class imbalance make data anomaly detection difficult. In this regard, this study proposes a convolutional neural network-based data anomaly detection method. The time and frequency domains data are transferred as images and used as the input of the neural network for training. ResNet18 is adopted as the feature extractor to avoid training with massive labelled data. In addition, the focal loss function is adopted to soften the class imbalance-induced classification bias. The effectiveness of the proposed method is validated using acceleration data collected in a long-span cable-stayed bridge. The proposed approach detects and classifies data anomalies with high accuracy.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.12
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• pp.3889-3903
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• 2022

To address the problem of low detection accuracy due to training noise caused by mislabeling when Tri-training for network intrusion detection (NID), we propose a Tri-training algorithm based on cross entropy and K-nearest neighbors (TCK) for network intrusion detection. The proposed algorithm uses cross-entropy to replace the classification error rate to better identify the difference between the practical and predicted distributions of the model and reduce the prediction bias of mislabeled data to unlabeled data; K-nearest neighbors are used to remove the mislabeled data and reduce the number of mislabeled data. In order to verify the effectiveness of the algorithm proposed in this paper, experiments were conducted on 12 UCI datasets and NSL-KDD network intrusion datasets, and four indexes including accuracy, recall, F-measure and precision were used for comparison. The experimental results revealed that the TCK has superior performance than the conventional Tri-training algorithms and the Tri-training algorithms using only cross-entropy or K-nearest neighbor strategy.

• The Journal of Internal Korean Medicine
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• v.33 no.4
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• pp.448-464
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• 2012

Objectives : This study reviews the latest articles in Korea and other countries that studied oriental medicine treatment on poststroke depression. Methods : Korean articles were retrieved from the 9 major Korean web article search engines. Foreign articles were retrieved from PubMed. Article published date was from 2000 up to September 2012. There were no restrictions on the types of publication, but articles not available in full text were excluded. The methodological quality was assessed according to Cochrane's assessment of risk of bias and Newcastle-Ottawa quality assessment scale. Results : Twenty-two articles were included in this study. Eleven articles were published in Korea, the rest were published in China. Nine articles were randomized controlled trials (RCT), one article was a non-randomized study (NRS), four articles were case reports, three articles were cross-sectional studies, two articles were comparative studies. In RCT articles, risk of selection bias and performance bias were generally high, risk of detection bias was unclear. The NRS article took four stars in Newcastle-Ottawa quality assessment. Comparison Hamilton rating scale for depression score between oriental medicine treated group and western medicine treated group revealed that there was no remarkable difference in mean score changes after treatment on PSD. Conclusions : The results of this study suggest that oriental medicine treatment is as effective as western medicine treatment for PSD. In the future, more rigorous oriental medicine treatment studies should be conducted.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.11 no.2
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• pp.11-21
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• 2016

Objectives : To determine the effectiveness of Chuna manual therapy for neck pain Methods : We searched 7 electronic databases(OASIS, NDSL, Ovid-MEDLINE, Ovid-EMBASE, Cochrane library, AMED, CNKI) to find all Randomized controlled trials that used Chuna manual therapy as a treatment for neck pain. The methodological quality of each RCT was assessed by the Cochrane risk of bias tool. Results : 7 RCTs met our inclusion criteria. The meta-analysis of 7 studies showed favorable results for the use of Chuna manual therapy. High risk of bias were observed for performance bias and detection bias. Conclusions : Our systematic review found favorable results using Chuna manual therapy for neck pain. But there are several limitations in our study due to lack of well-designed RCT. To obtain stronger evidence, further clinical trials would be needed.