• 전력전자학회논문지
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• 제22권3호
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• pp.240-248
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• 2017

This paper describes the development of a powertrain for a 20 kW experimental electric vehicle using a surface-mounted permanent magnet synchronous motor (SPMSM) and its application to a test vehicle. Two 10 kW SPMSMs are used in the powertrain, and two-level inverters are developed by using IGBTs to derive these motors. To control the SPMSM, a control board based on a TMS320F28335 DSP module, which has fast arithmetic function and floating point operator, is used. We develop a 100 V/40 A battery pack, which includes $32{\times}4$ LiFePO4 battery cells using commercial BMS. A commercial on-board charger with 220 V (AC) input and 100 V (DC) and 18 A output is used to charge the battery pack. The performance of the developed vehicle, such as acceleration availability, maximum speed, and maximum power, is estimated based on vehicle dynamics and verified through experiments.

• Journal of Power Electronics
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• 제17권2호
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• pp.442-452
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• 2017

This paper deals with the input-output modeling of a vector controlled PMSM drive system and design of a simple multiple model adaptive control (MMAC) scheme with desired transient responses. We present a discrete-time modeling technique using closed-loop identification that can experimentally identify the equivalent models in the d-q coordinates. A bank of linear models for the equivalent plant of the current loop is first obtained by identifying them at several operating points of the current to account for nonlinearity. Based on these models, we suggest a simple q-axis MMAC combined with a fixed d-axis controller. After the current controller is designed, another equivalent model including the current controller in the speed control loop shall be similarly obtained, and then a fixed speed controller is synthesized. The proposed approach is demonstrated by experiments. The experimental set up consists of a surface mounted PMSM (5 KW, 220V, 8 poles) equipped with a flywheel load of 220kg and a digital controller using DSP (TMS320F28335).

• Clinical and Experimental Reproductive Medicine
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• 제16권1호
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• pp.93-101
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• 1989

71 cycles of 67 women were treated for superovulation induction in our IVF & ET program from May to September in 1988. Endogenous LH surges were occurred in 21 cycles out of 71 cycles. And then, we selected 50 cycles without endogenous LH surge treated in the same period as control group. We compared egg recovery rate, egg maturity, fertilization rate, cleavage rate and pregnancy rate of study group with those of control group. We were able to detect more than 90% of endogenous LH surge by commencing daily LH monitoring on MCD 9. The egg recovery rate, egg maturity, fertilization rate, and pregnancy rate of the study group were not statistically different from those of the control group. Significantly lower cleavage rate was seen in the study group compared with that of control group. Above results suggested that the cycles with endogenous LH surge do not have to be abandoned and can be treated continuously to achieve successful pregnancy.

• 한국산학기술학회논문지
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• 제16권4호
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• pp.2951-2957
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• 2015

유해 유독 적조생물의 대발생은 해양생물 건강성과 수산어족자원에 심각한 피해를 입힌다. 본 연구에서는 미세조류의 대발생을 억제하기 위해 개발된 Thiazolidione 유도체(TD49)와 현장에서 적조생물을 제어하기 위하여 살포되는 황토에 대한 살조능을 조사하였다. 아울러 적조생물 생사판별과 관련된 자가영양생물의 광합성에 영향을 미칠 수 있는 활성엽록소(activity Chl. a), 광합성효율($F_v/F_m$), 전자 전달율(electron transport rate, ETR)등을 평가하였다. 대상적조생물은 유해조류 3종과 비유해 조류 1종을 선택하였으며, 유해조류는 침편모조류 Heterosigma akashiwo, Chattonella marina와 더불어 와편모조류 Heterocapsa circularisquama를 비교하였고, 비유해조류는 은편모조류 Rhodomonas salina에 대하여 평가하였다. 유해조류 3종은 살조물질(TD49)에 의하여 빠른 시간에 세포가 파괴되어 우수한 살조 효과(>80%)를 보인 반면, 황토에 관해서는 살조효율이 30%이하로 낮게 나타났다. 또한 TD49에 대한 유해조류 3종의 살조효율은 H. circularisquama> C. marina> H. akashiwo 순으로 높게 나타났으며, 광합성 효율 및 전자전달율 또한 극히 낮게 나타나, 광합성에 치명적인 영향을 미치는 것으로 사료되었다. 반면, 유해조류 3종에 관해서 황토에 대한 광합성 효율과 전자전달율은 대조군과 유의한 차이를 보이지 않았다(p>0.01). 비유해종 R. salina 은 대조군에 비하여 TD49와 황토의 살조 효과, 광합성효율 및 전자전달율의 차이는 명확하게 나타나지 않았고, 오히려 TD49물질에서 성장에 긍정적인 영향을 미치는 것을 확인하였다. 결과적으로 본 연구에서 TD49물질은 유해적조 생물을 선택적으로 제어 할 수 있으며, 현장 적용시 우수한 살조 효과를 가질 수 있을 것으로 판단된 반면, 황토는 적조생물 제어에 적합하지 않을 것으로 사료되었다.

• 한국식품저장유통학회지
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• 제24권3호
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• pp.472-482
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• 2017

본 연구는 국산 캠벨얼리 와인의 주질 개선과 기능성 향상을 위해 캠벨얼리 뿐만 아니라 안토시아닌과 폴리페놀 성분이 풍부하여 항산화능이 우수하다고 알려진 아로니아를 이용하여 상업용 효모인 S. cerevisiae Fermivin과 향미증진능을 지닌 P. anomala JK04를 각각 단독 또는 5:5(v/v)의 비율로 혼합발효한 후 블렌딩하는 실험을 진행하였다. 최적 블렌딩 비율을 정하기 위하여 예비실험으로 캠벨얼리 와인에 아로니아 와인을 각각 5, 10, 20%(v/v) 첨가하여 항산화능과 관능검사를 실시하였으며, 실험 결과를 바탕으로 캠벨얼리 와인과 아로니아 와인의 블렌딩 비율을 9:1(v/v)로 설정하였다. P. anomala JK04로 단독발효한 캠벨얼리 와인은 낮은 알코올 함량으로 인해 블렌딩에서 제외하였고, 나머지는 발효에 이용된 균주에 따라 블렌딩하였다. 블렌딩와인의 기능성을 평가하기 위하여 총 안토시아닌 함량, DPPH 라디칼 소거능, 총 페놀성 화합물 함량 분석을 진행하였으며, 모든 블렌딩와인에서 대조구인 S. cerevisiae로 단독발효한 캠벨얼리보다 높은 수치를 나타내었다. 블렌딩와인의 유리당 분석 결과에서는 P. anomala JK04로 단독발효한 아로니아 와인을 첨가한 시험구(A,D)에서 glucose와 fructose 같은 잔당이 남아있는 것을 확인하였으며, 유기산 분석 결과에서는 상기 두 시험구에서 특히 malic acid 함량이 높게 측정되었다. 블렌딩와인의 외관적 품질을 검사하기 위해 색도, 휘발성 향기성분, 관능검사가 수행되었으며, P. anomala JK04를 사용 여부에 따라 A, B, C와 D, E, F 순으로 hue와 intensity 값이 증가하는 경향을 나타내었다. 또한 Hunter's color value에서는 아로니아 와인의 첨가가 와인의 a value와 b value를 증가시키는 경향을 나타내었다. 휘발성 향기성분분석에서는 P. anomala JK04의 사용이 와인에 부정적인 성분인 aldehyde와 acid 함량이 소폭 증가시키긴 하였지만, 중요한 향기성분은 ester 화합물의 함량이 큰 폭으로 증가하는 것을 확인하였다. 관능검사 결과에서는 P. anomala JK04로 단독발효한 아로니아 와인을 사용한 시험구(A,D)에서 색, 맛, 신맛, 전반적인 기호도에서 다른 시험구보다 높은 점수를 받았으며, 향기 항목에서는 모든 블렌딩와인이 대조구보다 높은 점수를 받았다. 본 연구에서는 캠벨얼리 와인에 아로니아 와인을 블렌딩하여 기능성을 증가시켰으며, S. cerevisiae Fermivin과 P. anomala JK04를 혼합발효하여 향기성분의 증가 및 관능적 품질이 향상됨을 확인하였다.

• 에너지공학
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• 제16권2호
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• pp.83-92
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• 2007

석유자원 고갈에 따른 대체에너지 개발의 필요성과 더불어 온실가스인 $CO_{2}$ 저감 등 높은 환경개선 효과로 인하여 새로운 청정연료로 바이오매스로부터 제조되는 BTL(Biomass to Liquid)-디젤에 대한 관심이 유럽을 중심으로 크게 증가하고 있다. 본 논문에서는 BTL-디젤 기술 개발 현황 및 BTL 공정의 세부 공정기술들을 조사하였다. BTL 공정은 바이오매스 전처리 및 가스화, 합성가스 정제, F-T(Fischer-Tropsch) 합성 및 upgrading 공정 등으로 나눌 수 있으며, BTL 만의 차별적 기술로 합성가스 제조를 위한 가스화 공정과 함성가스 조성 조절을 포함하는 BTL 공정에 최적화된 F-T 합성 촉매 개발이 매우 중요하다. 대표적인 BTL 기술로 독일의 Choren 사는 Carbo-V 가스화 기술을 개발하여 세계 최초로 BTL 공정 상업화를 이루었으며, 네덜란드의 ECN은 tar와 BTX를 제거하기 위한 독자적인 OLGA 기술을 개발하여 가스화 시스템과 연계한 공정을 개발하였다. 또한 미국과 일본 등 많은 나라에서 경쟁적으로 기술개발을 재촉하고 있는 상황이다. 국내의 경우 이에 대한 연구는 전무하나 국내 에너지 안보를 위한 에너지 Mix 정책과 지구온난화 등 환경문제에 대응하기 위하여 BTL 기술 개발은 매우 중요한 의미를 가질 수 있으므로 독창적 기술의 선점이 매우 중요할 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제24권10호
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• pp.1425-1434
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• 2011

This experiment was designed to evaluate the effects of the processing method of common vetch seed (CVS) (Vicia sativa) on laying performance, egg quality, metabolic parameters and liver histopatology during the peak production period in hens. Lohman layers, 46 wk of age in 6 replicate cages each containing 4 hens, were allocated randomly to one of four dietary treatments. Diets were control (C) diet containing no common vetch and experimental diets containing 25% raw common vetch (RCV), 25% soaked in water for 72 h with exchange of water every 24 h (SCV) and 25% soaked&boiled at $100^{\circ}C$ for 30 minute common vetch (SBCV). Inclusion of RCV into the diet deteriorated all laying performance variables. SCV did not alleviate the adverse effect of raw common vetch on feed intake, egg weight, feed conversion, final weight and weight change. SCV partially alleviated egg production (p<0.001). SBCV diminished the adverse effect on feed intake, egg weight, feed conversion, final weight and weight change compared to raw vicia sativa (p<0.001). No significant difference was detected between SBCV and the control group in terms of egg production, feed conversion, final weight and weight change. Regardless of the processing method, all the common vetch groups had lower shell strength compared to the control group. Haugh units did differ between all groups (p<0.001). Inclusion of RCV and SCV into the basal diet decreased triglyceride, cholesterol, total protein and serum glucose concentrations (p<0.001). Hovewer, inclusion of SBCV into the basal diet increased these parameters. Liver samples were stained with Hematoxylin and eosin (HE) and evaluated by light microscopy. A biopsy of native liver tissue was used as a control. No histopathologic finding was present in the control group. Raw V. sativa compared with the control caused lipid accumulations in hepatocytes, severe congestion of hepatic blood vessels, inflammation, increased numbers of Kupffer cells and sinusoidal dilatations. Whereas, the livers from groups given treated V. sativa showed only different degrees of sinusoidal dilatations. Findings from the present study point out the risk of increased hepatic damage due to use of raw Vicia sativa. Increasing treatment of V. sativa lead to a decrease of liver damages. Inclusion of raw and soaked vetch seeds in rations affected adversely all parameters examined in laying hens. But alleviation was observed when soaked and boiled vetch seeds (SBCV) were fed. The results of these experiments indicated that soaked&boiled Vicia sativa seeds may safely be used at a 25% level in rations of laying hens.

• 대한약침학회지
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• 제22권3호
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• pp.166-170
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• 2019

Objectives: Attentional and memory functions are important aspects of neural plasticity that, theoretically, should be amenable to pharmacopuncture treatments. A previous study from our laboratory suggested that quantitative electroencephalographic (qEEG) measurements of theta/beta ratio (TBR), an index of attentional control, may be indicative of academic performance in a first-semester medical school course. The present study expands our prior report by extracting and analyzing data on frontal theta and beta asymmetries. We test the hypothesis that the amount of frontal theta and beta asymmetries (fTA, fBA), are correlated with TBR and academic performance, thereby providing novel targets for pharmacopuncture treatments to improve cognitive performance. Methods: Ten healthy male volunteers were subjected to 5-10 min of qEEG measurements under eyes-closed conditions. The qEEG measurements were performed 3 days before each of first two block examinations in anatomy-physiology, separated by five weeks. Amplitudes of the theta and beta waveforms, expressed in ${\mu}V$, were used to compute TBR, fTA and fBA. Significance of changes in theta and beta EEG wave amplitude was assessed by ANOVA with post-hoc t-testing. Correlations between TBR, fTA, fBA and the raw examination scores were evaluated by Pearson's product-moment coefficients and linear regression analysis. Results: fTA and fBA were found to be negatively correlated with TBR (P<0.03, P<0.05, respectively) and were positively correlated with the second examination score (P<0.03, P=0.1, respectively). Conclusion: Smaller fTA and fBA were associated with lower academic performance in the second of two first-semester medical school anatomy-physiology block examination. Future studies should determine whether these qEEG metrics are useful for monitoring changes associated with the brain's cognitive adaptations to academic challenges, for predicting academic performance and for targeting phamacopuncture treatments to improve cognitive performance.

• 대한치과의사협회지
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• 제58권6호
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• pp.324-335
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• 2020

We investigated whether fluoride varnishes recover the hardness of bovine teeth under 20 days of demineralization/remineralization cycling. The fluoride varnish groups (two commercial fluoride varnishes [V-varnish (Vericom, Korea) and CavityShield (3M ESPE, USA)] and an experimental fluoride varnish including 5 wt.% NaF were compared with a control group without fluoride varnish. Vickers hardness was measured at baseline, 3 days after immersion in caries-inducing solution, 24 hours after application of a fluoride varnish, and after 10 and 20 days of demineralization/remineralization cycling. Afterward, tooth surfaces were observed by scanning electron microscope. After fluoride varnish application and the cycling 10 and 20 days, the experimental varnish group showed the highest hardness, while the CavityShield and the control groups demonstrated the lowest hardness. The experimental varnish group recovered the hardness of the baseline at 24 hours after application of the varnish, while it was recovered after 20 days of the cycling in case of the V-varnish. However, the CavityShield and the control groups did not recover the hardness even after 20 days of the cycling. The experimental fluoride varnish with fast recovery in the hardness of the baseline can be used as an effective fluoride varnish to resist demineralization and to facilitate remineralization.

• Asian Pacific Journal of Cancer Prevention
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• 제17권10호
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• pp.4577-4581
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• 2016

Objective: The aim of this study was to assess thyroid function in breast cancer patients exposed to therapeutic external beam radiation. The focus was on possible progressive changes and any relationships between the incidence of primary hypothyroidism, the time required to become hypothyroid, and factors such as chemotherapy, hormonotherapy and immunotherapy. Materials and Methods: Seventy females undergoing 3D conformal and IMRT radiation therapy for breast cancers were enrolled in a non-randomized prospective study. The patients was divided into two groups: those after mastectomy or breast conserving surgery (BCS) were irradiated to a scar of the chest wall/breast and the ipsilateral supraclavicular and the axillary areas (supraclavicular radiotherapy group - SC-RT group - 32 patients) and the control group receiving adjuvant chest wall/breast RT only (BCT group - 38 patients).The total doses were 50.0 to 70 Gy in 5 to 7 weeks. The median follow-up term was 24 months (range, 1-40 months). Thyroid function was evaluated by measuring thyroid stimulating hormone (TSH), free thyroxine (fT4), and free triiodothyronine (fT3) levels. The minimum, maximum and mean thyroid gland doses for 20 Gy (V20) were calculated for all patients. Results: Statistically significant results were obtained for the SC-RT group. Two yearsa fter the end of RT the chance of an event was increased in 6% of the population (p=0.009) in the SC-RT group. In the BCT group no significance was noted. No statistically significant differences were found for V20, chemio-, immunotherapy and hormonotherapy or Ki67 values (p=0.12). No significant results were obtained for development of hypothyroidism and clinical factors (age, thyroid volume, treatment modalities). Conclusion: Radiotherapy is associated with a higher incidence of thyroid toxicity in breast cancer patients. Routine thyroid function monitoring should be recommended in such cases.