A Simplified Torque Ripple Reduction using the Current Shaping of the Flux Switched Reluctance Motor

Heon-Hyeong Lee,Qi Wang,Se-Joo Kim,Woongchul Choi,Geun-Ho Lee 한국자기학회 2012 Journal of Magnetics Vol.17 No.3

Recently, applications of the reluctance torque motor have been quite limited due to their inherent limitation of noise and vibration and thus, researches on the reluctance motor have been limited as well. However, with the tremendous increase in the cost of rare earth material magnets, studies of the reluctance torque motor are being conducted more and more. In principle, reluctance torque is generated when the inductance is changed. Therefore, in order to generate continuous torque in the switched reluctance motor, it is necessary to figure out the exact inductance level corresponding to the rotor position and the current level to be applied in that rotor position, respectively. If the current level or the rotor position is not accurately determined, then the generated reluctance torque becomes unstable and undesirable torque ripples prevail to eventually cause noise and vibrations. In this research, a flux switched reluctance motor (FSRM), which is classified into the switched reluctance motor (SRM), wasstudied. A methodology using the current shaping control according to the rotor position was proposed. Based on the proposed methodology, the optimal current waveform and the torque distribution function for the FSRM to minimize torque ripple was established and demonstrated in this paper.

센터 방식 전기자전거의 페달 토크 추정 알고리즘에 관한 연구

이헌형(Heon-Hyeong Lee),배태훈(Tae-Hoon Bae),천광수(Kwang-Su Chun),하주영,이근호(Geun-Ho Lee) 한국자동차공학회 2015 한국자동차공학회 부문종합 학술대회 Vol.2015 No.5

The study about metal artifact reduction by using Tin-Filter in CT scan

Sang-Heon Jeong(정상헌),Seong-Ju Lee(이성주),Hyeong-Min Jin(진형민),Jong-Hyo Kim(김종효),Heon-Jung Jeong(정헌정),Dong-Seong Kim(김동성) 대한CT영상기술학회 2019 대한CT영상기술학회지 Vol.21 No.1

목적: 본 논문에서는 CT 검사 시 Tin-Filter 적용에 따라 metal artifact를 감소시킬 수 있는지에 초점을 맞추고 연구를 진행하였다. 대상 및 방법: CT장비는 SIEMENS사의 Somatom Force를 사용하였다. IM Nail을 이용하여 자체 제작한 팬텀과 AAPM 팬텀을 CTDIvol 10 mGy을 기준으로 80 kV부터 150 kV까지 10 kV단위로 스캔하여 Noise와 SNR을 구하였으며 Tin-Filter는 150 kV에 적용되었다. 정밀도를 측정하기 위한 척도로 RMSE 기법이 사용되었고, PH5 팬텀의 Liver nodule, Portal vein 두 부분을 이용하여 리커트 척도로 정성적 평가를 실시하였다. 결과 값들은 통계프로그램 SPSS를 사용하여 분산분석(ANOVA)을 진행하였다. 결과: 자체제작 팬텀 및 AAPM 팬텀을 이용한 Noise 및 SNR 평가에서 kV가 올라감에 따라 Noise가 감소하는 경향을 보였으며 특히 Tin-Filter를 적용했을 때 52.3~79.9%까지 대폭 감소하였다(P<0.01). RMSE값은 140 kV에서 최댓값인 34.27, Tin-Filter가 적용된 Tin150 kV에서 최솟값인 5.95의 값을 보였다. 리커트 척도를 이용한 정성적 평가에서도 kV 그룹 간에는 통계적으로 차이가 없어 영상의 시각적 평가에서는 차이가 없는 것으로 나타났다(p=0.792). 결론: Tin-Filter를 적용하여 검사를 진행하였을 때 선량의 증가 없이 영상의 전체적인 질은 유지하면서 metal artifact를 감소시킬 수 있는 것으로 사료된다. Purpose: In this study, we focused on whether we can reduce the metal artifact by using Tin-Filter in CT scan Somatom Force(SIEMENS,Germany) was used for the CT equipment. Materials & Method: Noise and SNR were obtained by scanning the self-produced phantom using IM Nail and AAPM phantom in units of 10 kV from 80 kV to 150 kV based on CTDIvol 10 (mGy). Tin-Filter was applied to 150 kV.RMSE was used to measure the precision, and qualitative assessment was performed by using the Likert scale on liver noduleand portal vein of PH5 phantom. Result values were analyzed by ANOVA Test using statistical program SPSS. Noise and SNR evaluation using self-produced phantom and AAPM phantom showed a tendency of noise reduction with increasing kV. Result: Especially, when Tin-Filter was applied, it decreased 52.3%~79.9% (P<0.01). The maximum value of RMSE was 34.27 at 140 kV, and the minimum value of RMSE was 5.95 at the Tin150 kV with the Tin-Filter. In the case of qualitative assessment, there was no statistically significant difference in image evaluation (p=0.792). Conclusion: As a result, it is considered that the metal artifact can be reduced without degrading the overall quality of the image and increasing the Dose, if the scan is performed using the Tin-filter.

국내산 대두(Glycine max. Merr)자원의 플라보노이드 대사체 동정 및 열처리 효과

신재형 ( Jae Hyeong Shin ),김헌웅 ( Heon Woong Kim ),이민기 ( Min Ki Lee ),장가희 ( Ga Hee Jang ),이성현 ( Sung Hyen Lee ),장환희 ( Hwan Hee Jang ),황유진 ( Yu Jin Hwang ),박금룡 ( Keum Yong Park ),송범헌 ( Beom Heon Song ),김정봉 한국환경농학회 2015 한국환경농학회지 Vol.34 No.2

BACKGROUND: Soy isoflavones, structurally similar to endogenous estrogens, may affect human body through both hormonally mediated and non-hormonally related mechanisms. Heat processing could change chemical compositions. The effects of different thermal processes, boiling and HTHP(high temperature and high pressure) on the composition of isoflavone compounds and total amount of domestic soybeans were investigated in this study. METHOD AND RESULTS: Three different kinds of soybean samples were collected from RDA-Genebank. The samples were extracted using methanol, distilled water, and formic acid based solvent. Also the same solvents were used for mobile phase in UPLC/ToF/MS. All of the isoflavone compounds were analyzed based on the aglycone type of external standard for quantification. The standard calibration curve presented linearity with the correlation coefficient R2 > 0.98, analysed from 1 to 50 ppm concentration. The total isoflavone contents does not change by treatment within the same breed. While “boiling” and “HTHP” processes tend to increase the contents of aglycone and β-glucosides, “fresh” soybeans retained the high concentration of malonylglucosides. CONCLUSION: These results have to be considered while developing an effective functional food, from the health while point of view using soybeans.

백서 천식에서 면역 증강성 CpG 올리고 뉴클레오티드 투여의 효과

이신형 ( Lee Sin Hyeong ),김제형 ( Kim Je Hyeong ),정혜철 ( Jeong Hye Cheol ),김경규 ( Kim Gyeong Gyu ),정기환 ( Jeong Gi Hwan ),김병규 ( Kim Byeong Gyu ),이승헌 ( Lee Seung Heon ),박상면 ( Park Sang Myeon ),신철 ( Sin Cheol ) 대한결핵 및 호흡기학회 2001 Tuberculosis and Respiratory Diseases Vol.50 No.1

Sclerosing Adenosis Diagnosed by Needle Biopsy

Heon Jin Jung(정헌진),Won Shik Han(한원식),Hyeong-Gon Moon(문형곤),Soo Kyung Ahn(안수경),Ji-Sun Kim(김지선),Dong-Yong Noh(노동영),Jung-Min Chang(장정민),Nariya Cho(조나리야),Woo Kyung Moon(문우경),In-Ae Park(박인애),Hee-Chul Shin(신 대한종양외과학회 2012 Korean Journal of Clinical Oncology Vol.8 No.2

목적 : 본 연구는 침생검을 통해 진단 받은 경화성 선증에 대해 추가적인 수술 없이 경과 관찰했을 때의 잠재적 안정성을 알아보고자 하였다. 방법 : 1996년 1월부터 2010년 5월까지 침생검을 통해 경화성 선증으로 진단된 143명의 환자의 145개 병변을 대상으로 (core-needle biopsies 118례, vacuum-assisted biopsies 27례) 의무기록 검토를 토대로 한 후향적 고찰이다. 결과 : 환자들의 BI-RADS(The American College of Radiology Breast Imaging Reporting and Data System) 분류는 다음과 같다: C3(n=8), C4a(n=123), C4b(n=11), C4c(n=e), C5(n=1). 그 중 14명은 조직검사를 재시행하였고 BI-RADS 분류 C5이면서 영상의학적 소견과 병리학적 소견의 불일치를 보인 1명의 환자가 침윤성 유방암으로 진단되어 수술을 시행하였다. 나머지 환자들은 정기적인 초음파 검사 및 유방촬영술을 통해 경과 관찰하였고, 평균 추적관찰 기간 40개월 동안 144개의 병변의 최종 BI-RADS 분류는 다음과 같다: C1(n=5), C2(n=107), C3(n=32), 경과 관찰기간 동안 142명의 환자에서 악성 유방질환이 발견된 환자는 없었다. 결론 : 침생검을 통해 경화성 선증으로 진단된 환자에 있어서 추가적인 수술 없이 정기적인 검진을 통하여 경과 관찰하는 것은 잠재적 안전성을 가지고 있다. 하지만 조직검사와 영상검사 결과의 불일치 소견을 보이는 경우 수술적 생검을 통한 최종 진단이 필요하다. Background : The aim of this study was to assess the potential safety of follow up for patients diagnosed with sclerosing adenosis through needle biopsies without additional surgery. Patients and Methods : From January 1996 to May 2010, 145 lesions in 143 sclerosing adenosis patients who underwent core-needle biopsies (n=118), vacuum-assisted biopsies (n=27) in our institution were followed. Results : The American College of Radiology Breast Imaging Reporting and Data System (BI-BADS) classification in these patients was as follows : C3(n=8), C4a(n=123), C4b(n=11), C4c(n=e) and C5(n=1). After sclerosing adenosis was diagnosed by needle biopsy, 14 patients underwent re-biopsy. Only 1 patient who had BIRAD C5 sonographic features was diagnosed with invasive ductal carcinoma and surrounding ductal carcinoma in situ. The remaining 142 patients received regular medical exam with ultrasonography and/or mammography. 144 lesions’ BI-RADS category were C1(n=5), C2(n=107) and C3(n=32). With the median follow-up period of 40 months, none of the patients developed breast malignancy. Conclusions : Our study suggest that patients with sclerosing adenosis diagnosed by needle biopsies can be safely followed without additional surgery. However, in case of discordance with images and biopsy result, surgical excision for definite diagnosis is recommended.

Substance P alleviates the atopic like skin manifestation in TNCB-induced NC/Nga transgenic mice

( Hyeong Won Choi ),( June Hyuck Yim ),( Ki Heon Jeong ),( Eun Kyung Chung ),( Young Sook Son ),( Hyun Sook Hong ),( Min Kyung Shin ) 대한피부과학회 2015 대한피부과학회 학술발표대회집 Vol.67 No.2

Background: At very high concentrations, substance P (SP) induces histamine release, but low dose SP may be alleviates atopic dermatitis (AD) progression by trophic and immune modulatory functions by showing increase of IL-10 and the M2 type of macrophages and decrease of TNF-メ and IL-17 and increased regulatory T cells. Objectives: The aim of this study is to evaluate the topically applied SP could be reduced atopic like manifestation in animal model. Methods: The efficacy of SP on the manifestation of 2,4,6-trinitrochlorobenzene (TNCB)-induced dermatitis in NC/Nga mice were examined. Treatment effect was evaluated by measuring the dermatitis severity, scratching behavioral counts and trasnepidermal water loss. The changes of TGF-?, thymic stromal lymphopoietin (TSLP), activation-regulated chemokine (TARC) and IgE level were analysed. Results: Topical treatment of SP improved skin barrier in vivo and in vitro. Infiltrated immune cells and innervated small nerve fibers were reduced in AD-skin lesion. Expression of TSLP in epidermis, and TARC and IgE level in serum also decreased in the mice treated with SP. TGF-? secretion was significantly increased in skin keratinocytes and dermal fibroblasts. Conclusion: These results suggest that topically administered SP might diminish the overacting immune reactions in hapten-treated NC/Nga mice to develop the alternative drugs to treat AD.

ELiSyR: Efficient, Lightweight and Sybil-Resilient File Search in P2P Networks

( Hyeong S. Kim ),( Eunjin(ej) Jung ),( Heon Y. Yeom ) 한국인터넷정보학회 2010 KSII Transactions on Internet and Information Syst Vol.4 No.6

Peer-to-peer (P2P) networks consume the most bandwidth in the current Internet and file sharing accounts for the majority of the P2P traffic. Thus it is important for a P2P file sharing application to be efficient in bandwidth consumption. Bandwidth consumption as much as downloaded file sizes is inevitable, but those in file search and bad downloads, e.g. wrong, corrupted, or malicious file downloads, are overheads. In this paper, we target to reduce these overheads even in the presence of high volume of malicious users and their bad files. Sybil attacks are the example of such hostile environment. Sybil attacker creates a large number of identities (Sybil nodes) and unfairly influences the system. When a large portion of the system is subverted, either in terms of the number of users or the number of files shared in the system, the overheads due to the bad downloads rapidly increase. We propose ELiSyR, a file search protocol that can tolerate such a hostile environment. ELiSyR uses social networks for P2P file search and finds benign files in 71% of searches even when more than half of the users are malicious. Furthermore, ELiSyR provides similar success with less bandwidth than other general efforts against Sybil attacks. We compare our algorithm to SybilGuard, SybilLimit and EigenTrust in terms of bandwidth consumption and the likelihood of bad downloads. Our algorithm shows lower bandwidth consumption, similar chances of bad downloads and fairer distribution of computation loads than these general efforts. In return, our algorithm takes more rounds of search than them. However the time required for search is usually much less than the time required for downloads, so the delay in search is justifiable compared to the cost of bad downloads and subsequent re-search and downloads.

A Randomized Trial Evaluating the Antiviral Efficacy of Switching from Lamivudine plus Adefovir to Tenofovir Monotherapy in Lamivudine-resistant Chronic Hepatitis B Patients with Undetectable Hepatitis B Virus DNA

( Heon Ju Lee ),( Jeong Min Kim ),( Young Oh Kweon ),( Soo Young Park ),( Jeong Heo ),( Hyun Young Woo ),( Jae Seok Hwang ),( Woo Jin Chung ),( Chang Hyeong Lee ),( Byung Seok Kim ),( Jeong Ill Suh ) 대한간학회 2016 춘·추계 학술대회 (KASL) Vol.2016 No.1

Aims: Tenofovir (TDF) monotherapy is a standard treatment for patientswho have lamivudine (LAM)-resistant chronic hepatitis B (CHB).However, the efficacy of switching to TDF monotherapy for LAMresistant CHB patient with undetectable HBV DNA while on LAMplus adefovir (ADV) combination therapy (stable switching) is notclear.Methods: In this non-inferiority trial, LAM-resistant CHB patients whohad undetectable serum HBV DNA (<20 IU/mL) for more than 6months after initiating LAM plus ADV combination therapy wererandomized (in a 1:2 ratio) to continue LAM plus ADV combinationtherapy (LAM/ADV group, n=58) or TDF monotherapy (TDF group,n=111) and followed-up with serum biochemistry and HBV DNA in12 week intervals for 96 weeks. The primary endpoint of this studywas the proportion of patients with viral reactivation at week 96.Viral reactivation was defined as HBV DNA >40 IU/mL at two consecutivetimepoints, or persistent HBV DNA levels of 20-40 IU/mL atthree consecutive timepoints.Results: A total of 169 CHB patients were enrolled in this study including74 with compensated cirrhosis. There were no significant differencesbetween two groups in age, gender, biochemistry findingsand duration of LAM and ADV combination therapy at baseline.Twelve (20.7%) patients in the LAM/ADV group and 18 (16.2%)patients in TDF group were HBeAg-positive. Nine patients (4 in theLAM/ADV group and 5 in the TDF group) discontinued the study.After a mean follow up period of 96 weeks, there was no subjectin either group experienced viral reactivation in both groups. Onepatient achieved HBsAg seroconversion in TDF group (1/106, 0.94%).The number of patients with HBeAg loss at week 96 was 5/12(41.7%)and 3/17(17.6%) in the LAM/ADV and TDF groups, respectively. Twopatients (2/17, 11.8%) achieved HBeAg seroconversion in TDF group.Transient virological rebound occurred in 14 patients (6 patients inLAM/ADF group and 8 patients in TDF group) through 96 weeks,but all patients achieved HBV DNA undetectable at the next visit.There were no patients experienced an increase of serum creatininelevels of ≥0.5 mg/dL above baseline.Conclusions: Stable switching to TDF monotherapy for 96 weekshowed a comparable virological response to continuous LAM plusADV combination therapy in LAM resistant CHB patients with undetectableHBV DNA. (Trial registration number Clinicaltrial.gov IDNCT01732367)

Evaluation of flavonol and flavone glycosides in Korean pepper fruits and leaves (Capsicum annuum L.) using UPLCDAD-QTOF/MS

Heon-Woong Kim,Jung-Bong Kim,Jae-Hyeong Shin,Ga-Hee Jang,Min-Ki Lee,A-Ram Bak,So-Young Jeong,Jeong-Sook Choe 한국식품영양과학회 2015 한국식품영양과학회 학술대회발표집 Vol.2015 No.8