• Journal of Power Electronics
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• v.16 no.2
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• pp.473-479
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• 2016

In this paper, the PSC PWM method is chosen as the optimal modulation method for a 20MW VSC HVDC, with consideration of the harmonic distortion of the output voltage, the switching frequency, and the control implementation difficulty. In addition, a new PSC PWM method is proposed in order to achieve an easy application and to solve the redundant control problems encountered in the previous PSC PWM method. To verify the proposed PSC PWM method, PSCAD/EMTDC simulations for an 11-level MMC RTDS HILS test and an 11-level MMC prototype converter test were performed. As can be seen from the results of these tests, the proposed PSC PWM method shows good results in an 11-level MMC with redundant sub-modules.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.6
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• pp.756-761
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• 2013

This paper propose the new demodulation method that can detect resolver signal's peak at the time of position estimation when the position information is required during current controller period. The proposed method is performed in a synchronous demodulation way with exciting signal and also cover a capability which can compensate the lag element of exciting signal caused by the resolver's inductive component and filter circuit. This paper carried out the experiment to investigate the validity and performance of the suggested method by using the test board made up of DSP and demodulation circuit. The test results show that the proposed method is theoretically clear and work completely as expected from making sure of sampling resolver signal's peak at the time of position estimation. In addition, Software position tracking algorithm is executed with the demodulated signals generated by the suggested method and an exact position can be estimated.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.179-180
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• 2009

We propose the method of analysis, separation, and express from normalized and standard method to reduce the problem with the existing scene change detection and the complicated and variety of images of real change. In this paper, we propose a new local ${\lambda}^2$-test which was combined the ${\lambda}^2$-existing test methods and local color histograms. This method is robust method of abrupt and gradual detection and solve the problem of traditional method.

• Journal of the Korean Society of Clothing and Textiles
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• v.17 no.3
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• pp.459-469
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• 1993

The purpose of this study is to investigate the relationship between body-types and skirt-patterns by analyzing various fitting conditions of the skirt patterns in relation to the body-types. To achieve this, fitting tests were done on six types of skirt-patterns. The tests included four body-types selected according to the existing classification of the types of under part of the body. Sensory tests were performed on the existing patterns and new drafting method based on the results of the fitting tests. The results of the fitting tests and sensory test are as follows. 1. The existing skirt-patterns were relatively well-fitted except for certain parts in standard somatotype (body-type A). 2. The new drafting method, designed on the basis of the fitting test on the existing patterns, scored high on all of the eighteen items included in the test This signifies the excellence of the new drafting method. 3. In the case of the allocation between the front and the back, which is the difference between the educational patterns and industrial patterns, the best silhouette was achieved when the hip-line and the waist-line were same sized both in the back and in the front. However, in the case of body-type D it was better when there was a 1cm difference between the back and the front. 4. The number of darts that best fits young persons were found to be eight, to keep their side hip-curve smooth. Further, it is desirable to set the center line of the dart as the vertical waist-line. 5. The best length of the darts were determined to be 12.5cm, 11ch in the back, and 11cm, 9.5cm in the front. Adjustments would be made according to the differing body-types in the range of 0.5cm. 6. The lowerness of the back waist-line for the normal was determined at 1.5cm, with some variations in other body-types. 7. The front waist-line was needed to be 1cm lowered in the case of body-type B, whereas, in the case of body-type D, it was needed to be 1cm raised.

• Composites Research
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• v.12 no.2
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• pp.10-25
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• 1999

A new evaluation method for the interfacial properties of fibrous composites based on a fragmentation technique is proposed by using the gradual multi-fiber composite, in which the inter-fiber spacing is gradually changed. The results showed that as the inter-fiber distance increased, the aspect ratio of broken fibers decreased while the interfacial shear strength between the fiber and matrix increased. When the reciprocal of the inter-fiber destance was taken for the above relations, both the aspect ratio and interfacial shear strength showed a saturated value. This means that the gradual multi-fiber composite indicates an upper bound in aspect ratio and an upper bound in interfacial shear strength. It was concluded that this fragmentation test could be a new method for composite evaluation, since reducing a difference between these two bounds is effective for composite strengthening. In addition an elastoplastic finite element analysis was carried out to relate the above results with fiber stress a distribution around fiber breaks. It was proved that the bound obtained in the gradual multi-fiber composite test is closely related to stress concentrations caused by a group of multi-fiber breaks.

• Wind and Structures
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• v.13 no.6
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• pp.557-580
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• 2010

A new inflow turbulence generation method and a combined dynamic SGS model recently developed by the authors were applied to evaluate the wind effects on 508 m high Taipei 101 Tower. Unlike the majority of the past studies on large eddy simulation (LES) of wind effects on tall buildings, the present numerical simulations were conducted for the full-scale tall building with Reynolds number greater than $10^8$. The inflow turbulent flow field was generated based on the new method called discretizing and synthesizing of random flow generation technique (DSRFG) with a prominent feature that the generated wind velocity fluctuations satisfy any target spectrum and target profiles of turbulence intensity and turbulence integral length scale. The new dynamic SGS model takes both advantages of one-equation SGS model and a dynamic production term without test-filtering operation, which is particular suitable to relative coarse grid situations and high Reynolds number flows. The results of comparative investigations with and without generation of inflow turbulence show that: (1) proper simulation of an inflow turbulent field is essential in accurate evaluation of dynamic wind loads on a tall building and the prescribed inflow turbulence characteristics can be adequately imposed on the inflow boundary by the DSRFG method; (2) the DSRFG can generate a large number of random vortex-like patterns in oncoming flow, leading to good agreements of both mean and dynamic forces with wind tunnel test results; (3) The dynamic mechanism of the adopted SGS model behaves adequately in the present LES and its integration with the DSRFG technique can provide satisfactory predictions of the wind effects on the super-tall building.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.44 no.3
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• pp.98-105
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• 2021

The sensory stimulation of a cosmetic product has been deemed to be an ancillary aspect until a decade ago. That point of view has drastically changed on different levels in just a decade. Nowadays cosmetic formulators should unavoidably meet the needs of consumers who want sensory satisfaction, although they do not have much time for new product development. The selection of new products from candidate products largely depend on the panel of human sensory experts. As new product development cycle time decreases, the formulators wanted to find systematic tools that are required to filter candidate products into a short list. Traditional statistical analysis on most physical property tests for the products including tribology tests and rheology tests, do not give any sound foundation for filtering candidate products. In this paper, we suggest a deep learning-based analysis method to identify hand cream products by raw electric signals from tribological sliding test. We compare the result of the deep learning-based method using raw data as input with the results of several machine learning-based analysis methods using manually extracted features as input. Among them, ResNet that is a deep learning model proved to be the best method to identify hand cream used in the test. According to our search in the scientific reported papers, this is the first attempt for predicting test cosmetic product with only raw time-series friction data without any manual feature extraction. Automatic product identification capability without manually extracted features can be used to narrow down the list of the newly developed candidate products.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.891-894
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• 1999

According to increasing the integration of the device, there are important consideration about the improvement of the reliability in the product. To improve the reliability of the device, the test parameters and test time are increased. There are no pin-to-pin short test and pin-to-pin leakage test in the present test items to analysis the characteristics and reliability of the device. The purpose of the paper is to model the pin-to-pin phenomenon and propose to modify the test method present and to test the new pin-to-pin DC parameters. These modified and additive test items are applied to product test and confirmed to improve the reliability of product test.

• The KIPS Transactions:PartD
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• v.14D no.2
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• pp.191-202
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• 2007

In general, test data generation techniques require the specification of an entire program path for automated test data generation. This paper presents a new way for generating test data automatically een without specifying a program path completely. For the ends, this paper presents a technique for transforming a program under test into Alloy which is the first order relational logic and then producing test data via Alloy analyzer. The proposed method reduces the burden of selecting a program path and also makes it easy to generate test data according to various test adequacy criteria. This paper illustrates the proposed method through simple, but illustrative examples.

• The Korean Journal of Applied Statistics
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• v.24 no.6
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• pp.1045-1054
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• 2011

During clinical trials a researcher is frequently able to observe a disease symptom in a subject as well as a severity score for those who experienced a symptom after a fixed length of treatment. The traditional method to evaluate a decreasing trend in proportion, when there is an intrinsic order in the treatment groups (for example control and two or more treatment groups) is a Cochran-Armitage test, while the method to evaluate a decreasing trend in continuous non-normal data is a Jonckheere-Tersptra test. The Cochran-Armitage test emphasizes the dichotomous data of symptom occurrence and the Jonckheere-Tersptra test emphasizes the continuous non-normal data of severity symptom scores. In this paper we propose new test statistics that consider the combined evidence from a symptom occurrence and disease severity score. We illustrate these methods with example data of schizophrenic inpatients that demonstrated antipsychotic-drug induced constipation. A small-scale simulation is conducted to compare the new trend tests with other trend tests.