후박마황탕(厚朴麻黃湯)이 ovalbumin으로 유도된 천식 모델 생쥐에 미치는 영향

나가영,이혜인,김영광,문영호,Na, Ga-young,Lee, Hye-in,Kim, Young-kwang,Moon, Young-ho 대한한방내과학회 2018 大韓韓方內科學會誌 Vol.39 No.4

Hubakmawhang-tang (HMT), listed in Geumgweyoryak, is an oriental medicine used for the symptoms of asthma, such as cough and dyspnea. In this study, we investigated the HMT effects on ovalbumin-induced asthmatic in mice. We examined weight changes, airway hyperresponsiveness, histopathological abnormalities, immune cell infiltrations, immunoglobulin and inflammatory cytokine levels, and spleen body weight ratios in asthmatic mice. HMT inhibited airway hyperresponsiveness, immune cell infiltration, and airway remodeling and caused a significant lowering of serum IgE and IgG1 levels. The asthmatic mice had elevated IL-4 levels in lung tissue and this elevation was effectively prevented by HMT. HMT did not cause changes in body weight or in the spleen body weight ratio. Therefore, HMT might have an anti-asthmatic effect in the ovalbumin-induced mouse model.

농업용 트랙터 적용 정유압 기계식 변속기 연구 동향

오송현 ( Song-hyeon Oh ),신창섭 ( Chang-seop Shin ) 한국농업기계학회 2022 한국농업기계학회 학술발표논문집 Vol.27 No.2

농업용 트랙터는 작업기를 이용한 농작업이 주요 목적이다. 따라서 작업기로 동력을 전달하는 변속기가 매우 중요하다. 최근 트랙터의 변속기는 효율 및 편의성을 고려하여 무단변속기로 적용되고 있는 추세이다. 트랙터에 주로 적용되는 무단 변속기는 정유압 변속기(Hydro-static transmission)와 정유압 기계식 변속기(Hydro-mechanical transmission)가 있다. HST는 내구성이 우수하고 전·후진 조작이 용이하다는 장점이 있지만, 효율이 낮아 50마력 이하의 소형 트랙터에 주로 적용되고 있다. 이러한 단점을 보완하고 HST의 장점을 살려 개발된 변속기가 바로 HMT이다. HMT는 HST의 기동력과 기계식 변속기의 우수한 동력 전달이 결합된 구조로 출력비가 높고 무단변속이 부드러워 중·대형 트랙터에 적용될 수 있는 변속기이다. YANMAR에서는 45~113마력 트랙터 모델에 HMT를 탑재하여 출시하였고, 국제종합기계에서도 HMT를 탑재한 이앙기를 선보이고 있다. 이처럼 HMT는 상용화가 될 만큼 유용한 기술이라고 판단된다. 향후 HMT가 적용된 농업용 트랙터 개발의 가속화가 이루어질 것으로 예상되며, 특히 중·대형 트랙터에 적용되어 사용자의 수요를 만족하는 제품이 출시될 것으로 기대된다.

2-모드 기계 유압식 무단변속기의 효율분석

정규홍(Gyuhong Jung),김형의(Hyoungeui Kim),김종기(Jongki Kim) 한국자동차공학회 2004 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

Efficiency analysis of the developing HMT was performed by the solution of simultaneous equations derived from the kinematic and static torque relations considering the efficiency of gear and hydraulic units. The analysis results show that the overall HMT efficiency largely depends on the amount of power delivered by HSU and it could be improved for the HMT designed with more number of shift modes.

Modeling and Simulation for a Tractor Equipped with Hydro-Mechanical Transmission

최석환,김형진,안성현,홍성화,채민재,권오은,김수철,김용주,최창현,김현수 한국농업기계학회 2013 바이오시스템공학 Vol.38 No.3

Purpose: A simulator for the design and performance evaluation of a tractor with a hydro-mechanical transmission (HMT)was developed. Methods: The HMT consists of a hydro-static unit (HSU), a swash plate control system, and a planetary gear. It was modeled considering the input/output relationship of the torque and speed, and efficiency of HSU. Furthermore, a dynamic model of a tractor was developed considering the traction force, running resistance, and PTO (power take off)output power, and a tractor performance simulator was developed in the co-simulation environment of AMESim and MATLAB/Simulink. Results: The behaviors of the design parameters of the HMT tractor in the working and driving modes were investigated as follows; For the stepwise change of the drawbar load in the working mode, the tractor and engine speeds were maintained at the desired values by the engine torque and HSU stroke control. In the driving mode, the tractor followed the desired speed through the control of the engine torque and HSU stroke. In this case, the engine operated near the OOL (optimal operating line) for the minimum fuel consumption within the shift range of HMT. Conclusions: A simulator for the HMT tractor was developed. The simulations were conducted under two operation conditions. It was found that the tractor speed and the engine speed are maintained at the desired values through the control of the engine torque and the HSU stroke.

Modeling and Simulation for a Tractor Equipped with Hydro-Mechanical Transmission

Choi, Seok Hwan,Kim, Hyoung Jin,Ahn, Sung Hyun,Hong, Sung Hwa,Chai, Min Jae,Kwon, Oh Eun,Kim, Soo Chul,Kim, Yong Joo,Choi, Chang Hyun,Kim, Hyun Soo Korean Society for Agricultural Machinery 2013 바이오시스템공학 Vol.38 No.3

Purpose: A simulator for the design and performance evaluation of a tractor with a hydro-mechanical transmission (HMT) was developed. Methods: The HMT consists of a hydro-static unit (HSU), a swash plate control system, and a planetary gear. It was modeled considering the input/output relationship of the torque and speed, and efficiency of HSU. Furthermore, a dynamic model of a tractor was developed considering the traction force, running resistance, and PTO (power take off) output power, and a tractor performance simulator was developed in the co-simulation environment of AMESim and MATLAB/Simulink. Results: The behaviors of the design parameters of the HMT tractor in the working and driving modes were investigated as follows; For the stepwise change of the drawbar load in the working mode, the tractor and engine speeds were maintained at the desired values by the engine torque and HSU stroke control. In the driving mode, the tractor followed the desired speed through the control of the engine torque and HSU stroke. In this case, the engine operated near the OOL (optimal operating line) for the minimum fuel consumption within the shift range of HMT. Conclusions: A simulator for the HMT tractor was developed. The simulations were conducted under two operation conditions. It was found that the tractor speed and the engine speed are maintained at the desired values through the control of the engine torque and the HSU stroke.

Effect of heat-moisture treatment under mildly acidic condition on fragmentation of waxy maize starch granules into nanoparticles

Kim, J.H.,Park, D.H.,Kim, J.Y. IRL Press ; Elsevier Science Ltd 2017 Food hydrocolloids Vol.63 No.-

Waxy maize starch was modified by a heat-moisture treatment (HMT) under acidic conditions followed by homogenization to create starch nanoparticles. Waxy maize starch was heated at 130 <SUP>o</SUP>C for 3, 5, or 8 h under mildly acidic conditions (0.00, 0.10, or 0.15 N sulfuric acid solution) and homogenized for up to 60 min. The crystalline, molecular, and granular structures of starch were effectively changed without severe loss of starch substance (less than 25%) by the HMT under acidic conditions. The HMT under acidic conditions enhanced short-range order of starch granules based on the results of FT-IR but decreased the proportion of amylopectin long chains. The data suggest that the amorphous region of the starch granule was readily hydrolyzed by the acidic condition during the HMT. Moreover, homogenization after the HMT (0.15 N for 8 h) induced fragmentation of starch granules into nano-sized particles with diameters less than 40 nm.

The role of WRKY47 gene in regulating selenium tolerance in Arabidopsis thaliana

Xi Wu,Manzhi Tao,Yun Meng,Xiangyu Zhu,Liangwen Qian,Alia Shah,Wei Wang,Shuqing Cao 한국식물생명공학회 2020 Plant biotechnology reports Vol.14 No.1

Selenium stress has a serious impact on the growth of plants. However, the available understanding on the mechanism of Se stress response is still insufficient. In this study, we found that the WRKY47 gene plays an important role in maintaining Se homeostasis and tolerance in Arabidopsis thaliana. Expression of WRKY47 is induced by Se stress. The wrky47 mutants are sensitive to Se stress, and this sensitivity is associated with a decrease in the transcription levels of Se-detoxify genes HMT1 and HMT3. Surprisingly, the WRKY47-overexpression lines also showed increased sensitivity to Se stress and had increased Se content; this correlates to an increase in the transcription level of Se-uptake gene PHT1;4 but not Se-detoxify genes HMT1 and HMT3. Our results suggest that gain- and loss-of-function mutations in WRKY47 enhance the sensitivity of A. thaliana plants to Se stress through different mechanisms.

복압성요실금 환자에서 Kontinence HMT2000을 이용한 바이오피드백과 전기자극치료의 효과

배연경,이대형,박성철,진성희,고민환,이태형 영남대학교 의과대학 2003 Yeungnam University Journal of Medicine Vol.20 No.1

Background: To evaluate the efficacy of EMG biofeedback and pelvic floor electrical stimulation in the stress urinary incontinence patients by Kontinence HMT2000. Materials and Methods: A group of 14 patients with stress urinary incontinence were treated with combined biofeedback and intravaginal electrical stimulation during 12 sessions from 2 weeks to 6 weeks. Results: At immediate post treatment, subjective cure rate was 28% and improvement rate was 57% and failure rate was 15%. Thus the overall success rate for this treatment was 85%. The result of 3 months after treatment showed cure rate 14% and improvement rate was 43%. Intravaginal pressure increased by an average of 11.9 cmH2O. Increased vaginal pressure was found in 93% of the patients and more than 50% increment of intravaginal pressure was 71%. Conclusions: Combined biofeedback and pelvic floor electrical stimulation by use of Kontinence HMT2000 is effective for the patients who have good compliance, relative low degree stress urinary incontinence. In order to attain good results, a well structured program that teaches specific muscle exercise and the patients should be followed by regular interval reinforcement treatment.

SOM의 통계적 특성과 다중 스케일 Bayesian 영상 분할 기법을 이용한 텍스쳐 분할

김태형,엄일규,김유신,Kim Tae-Hyung,Eom Il-Kyu,Kim Yoo-Shin 대한전자공학회 2005 電子工學會論文誌-SP (Signal processing) Vol.42 No.6

이본 논문에서는 Bayesian 영상 분할법과 SOM(Self Organization feature Map)을 이용한 텍스쳐(Texture) 분할 방법을 제안한다. SOM의 입력으로 다중 스케일에서의 웨이블릿 계수를 사용하고, 훈련된 SOM으로부터 관측 데이터에 대한 우도(尤度, likelihood)와 사후확률을 구하는 방법을 제시한다. 훈련된 SOM들로부터 구한 사후확률과 MAP(Maximum A Posterior) 분류법을 이용하여 텍스쳐 분할을 얻는다. 그리고 문맥 정보를 이용하여 텍스쳐 분할 결과를 개선하였다. 제안 방법은 HMT(Hidden Markov Tree)을 이용한 텍스쳐 분할보다 더 우수한 결과를 보여준다. 또한 SOM과 HMTseg라고 불리는 다중스케일 Bayesian 영상 분할 기법을 이용한 텍스쳐 분할 결과는 HMT와 HMTseg을 이용한 결과보다 더 우수한 성능을 보여준다. This paper proposes a novel texture segmentation method using Bayesian image segmentation method and SOM(Self Organization feature Map). Multi-scale wavelet coefficients are used as the input of SOM, and likelihood and a posterior probability for observations are obtained from trained SOMs. Texture segmentation is performed by a posterior probability from trained SOMs and MAP(Maximum A Posterior) classification. And the result of texture segmentation is improved by context information. This proposed segmentation method shows better performance than segmentation method by HMT(Hidden Markov Tree) model. The texture segmentation results by SOM and multi-sclae Bayesian image segmentation technique called HMTseg also show better performance than by HMT and HMTseg.

시내 버스용 기계 유압식 무단변속기 해석

정규홍(Gyuhong Jung),김형의(Hyoungeui Kim),이근호(Geunho Lee) 한국자동차공학회 2004 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

HMT is a type of continuously variable transmission which has split power path characteristics with gear train and hydro static unit. The benefit of improved fuel economy and high power capacity enables it to be a promising application for large vehicles. This paper presents the analysis results including velocity, static torque and dynamic model of the HMT that is developed for city buses. The speeds of gear shafts, the static clutch torque and split power ratio for each mode are detailed here. Also, the dynamic simulation result for mode shift characteristics shows that little shift shock is observed because of the synchronized rotation speed in clutch.