• Title/Summary/Keyword: comparison of results

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Comparisom of Control Algorithm for Simultaneous Control of DC-DC Converter (DC-DC 컨버터 동시제어의 제어 알고리즘 비교)

  • Park, Hyo-Sik;Han, Woo-Yong;Lee, Gong-Hee
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.51 no.4
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    • pp.163-168
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    • 2002
  • This paper presents the comparison results of control algorithm for the simultaneous control of a multi output converter system that controls, simultaneously and independently, the separate Buck converter and Boost converter with the different specification by one DSP digital controller. As two separate converters are regulated by only one DSP, it is possible to achieve the simple digital control circuit for regulating the multi output DC-DC converter. By setting the software switch state, PI and Fuzzy controller can be applied as a controller for each converter without any change of hardware. Also, it is included the control characteristics comparison between PI and Fuzzy controller. The control characteristics of each PWM DC-DC converter is validated by experimental results.

Comparison and Analysis for Open-circuit Field of PM Machines with Halbach and Circumferential Magnetized Rotor (Halbach자화 및 원주방향 자화된 회전자를 갖는 영구자석 기기의 무부하시 자계분포 특성해석 및 비교)

  • Jang, Seok-Myeong;Choi, Jang-Young;Cho, Han-Wook;Yang, Hyun-Sup;Lee, Sung-Ho;Jeong, Sang-Sub
    • Proceedings of the KIEE Conference
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    • 2004.10a
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    • pp.86-88
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    • 2004
  • This paper deals with the comparison and analysis for open-circuit field of PM(permanent magnet) machines with Halbach and circumferential magnetized rotor. The governing equation is derived in terms of magnetic vector potential and 2-d polar coordinate. And then, analytical results has been verified by comparison with those obtained from FE(finite element) method. On the basis of 2-d analytical results, this paper confirms that PM machines with circumferential magnetized rotor is superior to it with Halbach magnetized rotor in terms of magnitude and sinusoidal wave-forms of flux density due to PM and required magnet volume.

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Comparison of Converter Topologies for Single Phase Switched Reluctance Motor (단상 SRM용 컨버터 특성비교)

  • Kim, Tae-Hyoung;Seok, Seung-Hun;Liang, Jianing;Lee, Dong-Hee;Ahn, Jin-Woo
    • Proceedings of the KIEE Conference
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    • 2009.04b
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    • pp.139-142
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    • 2009
  • Comparison of three converter topologies for single phase switched reluctance motor is proposed in this paper. Due to the limitation of do-link voltage, conventional asymmetric converter is difficult to build up enough phase current in the high speed operation. In order to solve this problem, boost converter is used to improve the performance. Two active boost converters are reviewed: one is series-connected type, another is parallel-connected. Otherwise, a novel active boost converter is proposed. The comparison of these converters is based on the voltage raring of capacitor, stability and converter topology. Because the converter selection depends on the motor design, the single phase 6/6 SRM is considered in this paper. Some simulations results are executed. And the results verified the analysis in this paper.

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Network Coding-Based Fault Diagnosis Protocol for Dynamic Networks

  • Jarrah, Hazim;Chong, Peter Han Joo;Sarkar, Nurul I.;Gutierrez, Jairo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.14 no.4
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    • pp.1479-1501
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    • 2020
  • Dependable functioning of dynamic networks is essential for delivering ubiquitous services. Faults are the root causes of network outages. The comparison diagnosis model, which automates fault's identification, is one of the leading approaches to attain network dependability. Most of the existing research has focused on stationary networks. Nonetheless, the time-free comparison model imposes no time constraints on the system under considerations, and it suits most of the diagnosis requirements of dynamic networks. This paper presents a novel protocol that diagnoses faulty nodes in diagnosable dynamic networks. The proposed protocol comprises two stages, a testing stage, which uses the time-free comparison model to diagnose faulty neighbour nodes, and a disseminating stage, which leverages a Random Linear Network Coding (RLNC) technique to disseminate the partial view of nodes. We analysed and evaluated the performance of the proposed protocol under various scenarios, considering two metrics: communication overhead and diagnosis time. The simulation results revealed that the proposed protocol diagnoses different types of faults in dynamic networks. Compared with most related protocols, our proposed protocol has very low communication overhead and diagnosis time. These results demonstrated that the proposed protocol is energy-efficient, scalable, and robust.

A Study on the Effects of Gamisoyosan on Ovariectomized Osteoporosis in Rats (가미소요산(加味逍遙散)이 난소적출로 유발된 흰 쥐의 골다공증에 미치는 영향)

  • Park, Chan-Soo;Sohn, Young-Joo
    • The Journal of Korean Obstetrics and Gynecology
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    • v.21 no.1
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    • pp.1-15
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    • 2008
  • Purpose: Osteoporosis that occurred after menopause is one of the most common metabolic disease. and it is that bone mass significant decrease in comparison with normal people. Its symptoms are fracture, decrease of height, etc. The purpose of this study is to examine what are the effects of the Gamisoyosan on the aged ovariectomized rat model of postmenopausal osteoporosis. Methods: 24 female rats were ovariectomized and divided into normal group(normal), ovariectomized group(control), and treated with Gamisoyosan group(treated). During 8 weeks we dosed D.W to sham and control group, and dosed Gamisoyosan(105 mg/100 g) to experimental group. After 8 weeks we sacrificed rats and measured the body weight, albumin, P, Calcium, ALP, total cholesterol, triglyceride, AST, ALT, T4, estradiol, the femur weight, the tibia ash weight, trabecular bone area, trabecular thickness, osteoclast number. Results: The level of serum albumin, calcium, AST, ALT, estradiol in Gamisoyosan group showed significant increase in comparison with control group. The level of serum triglyceride in Gamisoyosan group showed significant decrease in comparison with control group. Trabecular bone area and osteoclast number in Gamisoyosan group showed significant increase in comparison with control group. Conclusions: Reviewing these experimental results, Gamisoyosan has shown to activate osteogenesis and prevent bone resorption, and it should show efficacy on prevention and improvement of osteoporosis after menopause.

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Comparison between a spherical head model and a prolate spheroidal head model used in HRTF customization (맞춤형 머리전달함수에 사용될 수 있는 장구 회전타원체 형상 머리모델과 구형 머리모델 간의 비교)

  • Jo, Hyun;Park, Young-Jin;Park, Youn-Sik
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.11a
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    • pp.1009-1013
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    • 2007
  • To do a HRTF customization, researchers used a spherical head model for modeling the head block of structural modeling of HRTF, which is the one of the technique for HRTF customization, because of its simplicity. In this paper, an analytic spheroidal HRTF caused by an incident point source will be introduced. Using proposed spheroidal HRTF, near-field HRTF customization can be applicable through a structural modeling of HRTF. To see the necessity of sheroidal head model, comparison of two analytic solutions, which are classical spherical HRTF and proposed spheroidal HRTF, will be shown. On the view point of ITD, optimal head model which matches with the measured ITD of KEMAR HRTF can be obtained. ITD results show that there are only slight differences between spherical and spheroidal head model. Magnitude comparison is made by constructing head model using measured head size. Although magnitude comparison is not studied between optimal models, the results of 24 of 36 subjects are shown that spheroidal head model matches notch frequency pattern of measured HRTF better than those of spherical one, where the sound source is at contralateral position.

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The Clinical Study on Yangdorak Change with Idiopathic Facial Paralysis Patients (특발성안면신경마비환자의 양도락 변화에 대한 임상적 고찰)

  • Kim, Kyung-Ok;Yang, Jae-Chul;Mun, Kyung-Suk;Lee, Kyung-Yun;Jang, Jo-Ung
    • Journal of Acupuncture Research
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    • v.22 no.6
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    • pp.201-209
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    • 2005
  • Objectives : We investicated correlation between Yangdorak and Meridian at Idiopathic facial nerve paralysis patients. Methods : For Yangdorak examination, We made a comparison between 21 patients who were diagnosticated to Idiopathic facial nerve paralysis and 22 persons who were not. Results : 1. The stress showed the highest frequency in premonitory cause at onset. 2. In comparing results on the Yangdorak general mean, they were not statistically significant between two group(p<0.05). 3. In comparing results on the Stomach(ST)-meridian Yangdorak mean, Idiopathic facial nerve paralysis group is stastically significant in comparison with non-facial paralysis group(p<0.05). 4. In comparing results on the Small Intestine(SI)-meridian Yangdorak mean, Idiopathic facial nerve paralysis group is not stastically significant in comparison with non-facial paralysis group(p<0.05). Conclusion : Yangdorak may be used for a method to objective clinical examination. But further studies are required for a use of practical indicator.

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Auditory Perception Experiment on Attribute of Road Traffic Noise Causing Annoyance with Identical Linear Sound Pressure Level (동일한 선형 음압 레벨의 도로교통소음의 성가심 유발 인자에 관한 연구)

  • An, Jang-Ho;Schang, Seo-Il;Ko, J.H.;Chun, Hyung-Jun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.11a
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    • pp.641-648
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    • 2006
  • This study investigates which sound quality indices except SPL raise annoyance response. For investigation, auditory perception experiments for road traffic noise with identical linear SPL were performed by Paired Comparison Method. The numerical results of a Paired Comparison experiment express relative preference about annoyance. So that these relative preference scores are to be correlated to sound quality indices, which are absolute, a transformation is required to go from the relative domain to an absolute and linear scale of preference. The results of the transformation will be the 'merit values,' which quantifies the annoyance(in this case) of the road traffic noise on a linear scale. Using multiple regression, a formula is established that can calculate predicted merit values. Furthermore, This investigation offers a method selecting sound samples that represent various sound quality indices values to use experiment.

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A Study on User Liking Based on Anthropomorphism of Virtual Humans:Focusing on Social Comparison Experience and Self-Improvement Motivation (가상인간의 의인화에 따른 이용자 호감도에 관한 연구: 사회비교 경험과 자기향상욕구를 중심으로)

  • Jeong, DongA;Kim, Hayeon;Lee, Sang Woo
    • The Journal of Information Systems
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    • v.32 no.4
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    • pp.163-188
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    • 2023
  • Purpose The study examines the impact of the level of anthropomorphism (both in appearance and behavior) of virtual humans on user liking. It investigates whether this relationship is mediated by social comparison experiences, with the moderated mediation effect of users' desire for self-improvement. Design/methodology/approach A between-groups experimental design was employed to examine the impact of different levels of appearance(low/mid/high) and behavior(low/high) anthropomorphism on user liking of virtual humans. The experiment was conducted in an online environment, and participants were randomly exposed to one of six stimuli, which were Instagram-like posts. Findings The results indicate that as virtual humans become more anthropomorphic, they have a positive impact on user liking. However, once the level of anthropomorphism in appearance reaches a certain point (mid vs high), there is no significant difference in user liking. Users who perceive virtual humans as highly anthropomorphic tend to engage in more social comparison experiences, which positively affects their liking for these virtual humans. Conversely, individuals with a high desire for self-improvement found that the positive effect of appearance anthropomorphism on liking through social comparison experiences was reduced. The study extends the application of social comparison theory by examining its impact on influencer marketing with virtual beings. It provides valuable insights for the formulation of influencer marketing strategies using virtual humans.

The Effects Of Chekamuiyiin-tang On Biochemical And Histological Changes Of Rats Fed High Diet (체감의이인탕이 고지방식이로 유발한 비만 흰쥐의 생화학 및 조직화학적 변화에 미치는 영향)

  • 최원호;서부일
    • The Journal of Korean Medicine
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    • v.21 no.3
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    • pp.31-39
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    • 2000
  • Objectives : Chekamuiyiin-tang has effects of promoting diuresis, promoting blood circulation, elimating phlegm and strengthening the body's resistance to disease. We experimented with Chekamuiyiin-tang in order to find effects which might possibly cure obesity. Methods : We fed a control group of rats a high fat diet and administered normal saline for 8 weeks. And we fed an experimental group of rats a high fat diet and administered an extract of Chekamuiyiin-tang for 8weeks. Results : The serum total cholesterol level, triglyceride level, free fatty acid level, total lipid level and phospholipid level in the Chekamuiyiin-tang group showed a significant decrease in comparison with the control group. The serum HDL-cholesterol level in the Chekamuiyiin-tang group showed no change in comparison with the control group. The serum LDL-cholesterol level in the Chekamuiyiin-tang group showed a decrease in comparison with the control group, but this result showed no efficacy. The size of the epididymal fat cell and the fat drops area in the hepatic lobule of rats in the Chekamuiyiin-tang group showed a significant decrease in comparison with the control group. Conclusios : According to the above results, Chekamuiyiin-tang has shown to be capable of curing and preventing obesity.

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