• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.10
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• pp.8-12
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• 2007

In this paper, we proposed an frequency offset estimation scheme which can be used for packet based OFDM communication systems such as IEEE802.11a and IEEE802.11p physical layer. Proposed estimation scheme can adjust the gain allocation ratio between long training symbol and short training symbol while maintaining average power of overall training sequence so that we can obtain the reference parameters for MSE performance improvement. The preamble structure considered in this paper is based on the preamble specified in IEEE802.11a and IEEE802.11p standardization group. From the simulation results, it is shown that power ratio between long training symbol and short training symbol must vanes for achieving lower frequency offset estimation error as channel SNR condition is changed. Also it is known oat proposed scheme can achieve better performance than conventional one.

• Industrial Engineering and Management Systems
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• v.10 no.3
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• pp.209-220
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• 2011

Self-tapping screws have some operational peculiarities. In spite of their economical advantage that requires no prior tapping operation, a weakness of self-tapping screw-tightening operations is that screws can easily be tightened at a non-right angle, thus resulting in an improper tightening strength. Increases in outsourced workers have reduced labor costs, but the accompanying high worker fluidity means that new workers are more frequently introduced into factories. It is necessary to train new workers for self-tapping screw-tightening operations, which occupies a considerable portion of ordinary assembly works. The purpose of this study is to develop and implement a skill transfer system for the operation. This study (1) proposes a set of characteristic values for evaluating the quality of the operation and develops a device that can measure these values; (2) proposes criteria for evaluating the resultant quality of the tightening; and (3) develops a skill training system for better work performance. Firstly, sets of characteristic values for evaluating the quality of the operation, namely, torque, vertical pressure forces and horizontal vibration forces, are proposed. A device that can measure these values is developed. Secondly, criteria for evaluating the resultant quality of the tightening are identified, involving tightening torque, maximum vertical pressure and timing, vibration area during the processing and tightening period, and work angle. By using such parameters, workers with the proper aptitude can be identified. Thirdly, a skill training system for the operation is developed. It consists of screwdriver operation training and screw-tightening training with feedback information about the results of the operation. Finally, the validity of the training system is experimentally verified using new operators and actual workers.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.12
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• pp.4921-4926
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• 2015

Background: Breast cancer is the most common cancer type among women with increasing incidence rates, improved prognosis and survival. According to the localization of the tumor, breast cancer is designated as unilateral (UBC) or bilateral (BBC). BBC can be classified as synchronous (SBBC) or metachronous (MBBC) based on the time interval between the diagnosis of the first and the secondary tumors. According to the guideline of WHO 2012, BBC is generally defined as SBBC when contralateral breast carcinoma is diagnosed within 3 months. The aim of this study was to compare the characteristics and patterns of metastasis of BBC patients with UBC. Materials and Methods: A cohort of 768 patients with breast cancer treated at the Turkish Ministry of Health-Izmir Bozyaka Research and Training Hospital between 1976 and 2012 were studied. Survival analysis was performed comparing UBC and BBC patients. In addition, evaluations were performed in patients with SBBC and MBBC sub-groups. We used a 3-months interval to distinguish metachronous from synchronous. Results: When clinical and histopathological parameters were statistically evaluated, ER status, event-free and overall survival were found to be significant between UBC and BBC patients. In comparison of SBBC and MBBC patients, age, histological type of tumor, event-free and overall survival were found to be significant. Conclusions: BBC cases were found to show worse prognosis than UBC cases. Among BBC, SBBC had the worst prognosis based on overall survival rates.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.5143-5148
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• 2012

Objective: The aim was to investigate indicators related to DNA damage and cancer pathogenesis in Type II diabetes cases with breast cancer. It was planned to evaluate the relationship between these markers with oral antidiabetic drugs. Research Design and Methods: Fourty patients and 10 healthy individuals were included in the study. HIF-$1{\alpha}$ and 8-OHdG are examined in blood samples taken from these individuals with an ELISA Kit. Statistical analysis of data was performed with 95% confidence using Windows package program SPSS 15.0. Results: HIF-$1{\alpha}$ parameters were found to be meaningfully higher in the patient group than the controls in both pretreatment and posttreatment periods (p<0.05). No significant differences in terms of 8-OHdG between patients and controls. However, posttreatment serum HIF-$1{\alpha}$ ve 8-OHdG levels was found lower than pretreatment levels in patients receiving metformin, but not with pioglitazone. Conversely, serum 8-OHdG levels decreased significantly in these patients. When patients were evaluated according to the treatment groups (pioglitazone vs. metfformin) no significant differences in terms of serum HIF-$1{\alpha}$ and 8-OHdG levels between treatment groups. Conclusions: HIF-$1{\alpha}$ levels decreased significantly in the patient group receiving metformin. However, there was no significant difference in terms of HIF-$1{\alpha}$ levels in the patients receiving pioglitazone.

• Journal of Information Technology Applications and Management
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• v.14 no.4
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• pp.43-59
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• 2007

The purpose of the study was to examine the effectiveness of Neuro Feedback training by observing the pre and post brainwave measurement results of about 50 (experimental group 25. comparative group 25) subjects who have shown psychological difficulties in studying. attention deficit, and personalities. The study took place at Neuro Feedback training Center B. in between the months of July 2006 and May 2007. The methodology involved in the study included the Coloring Analysis Program of the Brain Quotient Test. As the brain waves are adjusted by timeseries linear analysis. the brain function quotients can reflect the functional states of the brain. Through the test, three parameters relaxation, attention and concentration-were initially measured for one minute each and the lowest parameter out of the three was selected as the training mode or improvement target. The training took place two or three times a week. for about 40 to 60 minutes per session. Because the clients have come to the training center at different times. the researcher sampled the results of only those who had attended more than 30 training sessions. The tool used to measure the psychological reaction was POMS (Profile of Mood State). while the tool used to measure the emotional and attention-deficit characteristics was the Amen Clinic ADD Type questionnaire. Hypothesis testing included t-test. The result of the study showed the Theta: SMR ratio of (left)p = .013. (right) p = .019. The result also confirmed the differences of both ATQ(left) p = .011. (right)p = .030 and SQ(left) p = .017. (right) p = .022. The result confirmed of emotional p = .000. attention-deficit characteristics p = .000. The result of the study suggest Neuro Feedback technique's possibility in positively affecting the subjects' mental state and attention-deficit characteristics.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.12
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• pp.174-179
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• 2014

In this study, we measure the radiation dose for every experiments performed during the training education in radiologic science and estimate the radiation dose to each participant in the training education to propose a safe curriculum including operation of the training education. In this paper, we optimized the three parameters and the results show the dramatically reduced radiation dose to each participant. The proposed arrangement of the subjects and operation of the training education will be very helpful to reorganize the curriculum and the subject operation and will protect the students from the radiation dose.

• The Journal of Korean Physical Therapy
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• v.29 no.5
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• pp.246-254
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• 2017

Purpose: Previous studies have reported that action observation training has beneficial effects on enhancing the motor task, such as balance and gait functions. On the other hand, there have been few studies combined with action observation training and auditory feedback. The purpose of this study was to determine the effects of action observation training with auditory feedback on the gait function in stroke patients with hemiparesis Methods: A total of 24 inpatients with post-stroke hemiparesis were assigned randomly to either an experimental group 1 (EG 1, n=8), experiment group 2 (EG 2, n=8), control group (CG, n=8, EG 1). The EG 2 and CG watched video clip demonstrating three functional walking tasks with auditory feedback, without auditory feedback, and showing a landscape image, respectively. The exercise program consisted of 30 minutes, five times a week, for four weeks. The participants were measured to 10MWT (10 m walk test), 6MWT (6 minutes walking distance test), TUG (timed up and go test), DGI (dynamic gait index), time and steps of F8WT (figure-of-8 walk test). Results: In the intra-group comparison after the intervention, EG 1 and EG 2 showed a significantly different gait function (10MWT, 6MWT, DGI, TUG, F8WT) (p<0.05). In the inter-group comparison after intervention, EG 1 showed significant improvements in the entire gait parameters and EG 2 only showed significant improvement in DGI and TUG compared to CG (p<0.05). Conclusion: These findings show that action observation training with auditory feedback may be used beneficially for improving the gait function of stroke patients with hemiparesis.

• Journal of Korean Association for Spatial Structures
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• v.20 no.2
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• pp.51-58
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• 2020

Recently, deep learning that is the most popular and effective class of machine learning algorithms is widely applied to various industrial areas. A number of research on various topics about structural engineering was performed by using artificial neural networks, such as structural design optimization, vibration control and system identification etc. When nonlinear semi-active structural control devices are applied to building structure, a lot of computational effort is required to predict dynamic structural responses of finite element method (FEM) model for development of control algorithm. To solve this problem, an artificial neural network model was developed in this study. Among various deep learning algorithms, a recurrent neural network (RNN) was used to make the time history response prediction model. An RNN can retain state from one iteration to the next by using its own output as input for the next step. An eleven-story building structure with semi-active tuned mass damper (TMD) was used as an example structure. The semi-active TMD was composed of magnetorheological damper. Five historical earthquakes and five artificial ground motions were used as ground excitations for training of an RNN model. Another artificial ground motion that was not used for training was used for verification of the developed RNN model. Parametric studies on various hyper-parameters including number of hidden layers, sequence length, number of LSTM cells, etc. After appropriate training iteration of the RNN model with proper hyper-parameters, the RNN model for prediction of seismic responses of the building structure with semi-active TMD was developed. The developed RNN model can effectively provide very accurate seismic responses compared to the FEM model.

• Journal of Korean Physical Therapy Science
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• v.12 no.4
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• pp.33-41
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• 2005

The purpose of this report was to describe the gait pattern and parameters of the complicated bilateral amputee with right transtibial and left tarsometatarsal amputation. Using a Vicon 370 three dimensional gait analysis system, the gait analysis was performed at pre and post-test. Treadmill Training with 15 degree, incline was practiced for 8weeks, 3times per week. In linear parameters, the Velocity, Stride length and Single limb support were increased than pre-test. but Cadence and Double limb support were less post-test than pre-test. In kinematics, the maximal pelvic tilt angle showed right side $21.87^{\circ}$, left side $20.67^{\circ}$ at pre-swing phase, and decreased as compared with pre-test. Especially, the inimal hip flexion angle showed right side $-6.83^{\circ}$, left side $1.52^{\circ}$ at pre-swing phase and increased as compared with pre-test. The maximal knee flexion angle disclosed right side $2.66^{\circ}$, left side $21.71^{\circ}$ at stance phase, and decreased as compared with pre-test. In kinetics, the hip extension moment on initial contact stage was right side 0.938NM/Kg, left side 0.09NM/Kg, which was impaired compared with normal person.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.61.1-61.1
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• 2017

As the application of deep-learning methods has been succeeded in various fields, they have a high potential to be applied to space weather forecasting. Convolutional neural network, one of deep learning methods, is specialized in image recognition. In this study, we apply the AlexNet architecture, which is a winner of Imagenet Large Scale Virtual Recognition Challenge (ILSVRC) 2012, to the forecast of daily solar flare occurrence using the MatConvNet software of MATLAB. Our input images are SOHO/MDI, EIT $195{\AA}$, and $304{\AA}$ from January 1996 to December 2010, and output ones are yes or no of flare occurrence. We consider other input images which consist of last two images and their difference image. We select training dataset from Jan 1996 to Dec 2000 and from Jan 2003 to Dec 2008. Testing dataset is chosen from Jan 2001 to Dec 2002 and from Jan 2009 to Dec 2010 in order to consider the solar cycle effect. In training dataset, we randomly select one fifth of training data for validation dataset to avoid the over-fitting problem. Our model successfully forecasts the flare occurrence with about 0.90 probability of detection (POD) for common flares (C-, M-, and X-class). While POD of major flares (M- and X-class) forecasting is 0.96, false alarm rate (FAR) also scores relatively high(0.60). We also present several statistical parameters such as critical success index (CSI) and true skill statistics (TSS). All statistical parameters do not strongly depend on the number of input data sets. Our model can immediately be applied to automatic forecasting service when image data are available.