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拖拉机动量飞轮主动防侧翻控制与模型试验研究 总被引：1，自引：0，他引：1
针对拖拉机侧翻致死致伤事故仍时有发生的问题，基于旋转刚体加速时的反向施矩原理，以反作用动量飞轮为执行元件，提出了从主动安全角度解决拖拉机侧翻问题的研究方法。通过构建拖拉机动力学系统数学模型，解析了整机侧翻行为的动态演变机理。为保证拖拉机主体结构的完整性，将动量飞轮置于拖拉机前部，取代传统静态配重的同时可主动提供防侧翻力矩。应用Matlab/Simulink软件，对反作用飞轮的回稳过程进行了基于PID控制的有效性仿真分析，同时设计并搭建了比例模型试验平台，对主动施矩飞轮的回稳控制效果进行了试验验证。结果表明，装备飞轮的拖拉机与无控制组对比，在一次试验中可多次实现整机的防侧翻控制，使整机防侧翻性能得到明显改善，且不同行驶工况下的试验数据与仿真结果的相关性较强，充分验证了本文拖拉机侧翻动力学模型的有效性。 相似文献
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José Carlos Hernández Sabrina Clemente Carlos Sangil Alberto Brito 《水产资源保护:海洋与淡水生态系统》2008,18(7):1091-1108
- 1. The aim was to determine the status of subtidal rocky benthic assemblages in three marine protected areas (MPAs) of the Canary Islands: (1) La Graciosa; (2) Mar de Las Calmas; (3) La Palma. Sea urchin (Diadema aff. antillarum) populations and non‐crustose macroalgal cover were surveyed, and used as an indicator of conservation status in the three MPAs as well as in a highly fished area (HFA‐Tenerife Island).
- 2. Comparing characteristics between each MPA and the HFA, and considering issues of management and design, it was concluded that the three MPAs each have a different conservation status. ‘Mar de Las Calmas’ marine reserve was found to have the most desirable conservation status, followed by ‘La Palma’ marine reserve based on sea urchin populations and non‐crustose macroalgae assemblages.
- 3. Conversely, ‘La Graciosa’ had the highest density of D. aff. antillarum and the lowest cover of non‐crustose macroalgae out of the three MPAs. Values were comparable to those at the HFA, which shows ‘La Graciosa’ to have the undesired conservation status.
- 4. Different spatial distribution patterns of non‐crustose macroalgal as well as different algal composition cover were observed between the three MPAs and the HFA. These differences were principally attributed to the intensity of grazing activity of the key herbivore D. aff. antillarum. It is suggested that the different study areas correspond to different phase shifts that imply differing resilience of systems that should be taken into a count in future conservation strategies.
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Joo Young LEE Kee Hwan PARK Taehwan OH Siyeon YANG Jeongmin SUH Hee Jin HAM Chanhee CHAE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(3):427
The aim of this study was to reproduce severe pneumonic lesions, similar to those during naturally-occurring porcine respiratory disease complex, in pigs dually inoculated with porcine reproductive and respiratory syndrome virus and Mycoplasma hyopneumoniae at 6 weeks of age, followed by inoculation with porcine circovirus type 2 at two weeks after. Time and sequence of infection with three pathogens mirror Asian field conditions. Microscopically, interstitial pneumonia and peribronchiolar lymphoid hyperplasia are considered the most characteristic lung lesions in infected pigs. The results of the present study demonstrate that inoculation of pigs with these three pathogens can lead to severe interstitial pneumonia with peribronchial or peribronchiolar lymphoid hyperplasia and fibrosis. 相似文献
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粳稻发芽期耐碱性的QTL检测 总被引：2，自引：0，他引：2
以粳粳交高产106/长白9号的200个F2:3株系为作图群体,在0.15% Na2CO3溶液碱胁迫下,进行了水稻发芽率及其相对碱害率的鉴定评价,并以SSR标记构建的分子连锁图谱为基础,对水稻发芽率及其相对碱害率进行了数量性状基因座(QTL)检测。结果表明,在F3株系群中水稻发芽率及其相对碱害率均呈单峰接近正态的连续分布。共检测到碱胁迫下与水稻发芽率相关的QTL 7个,对表型变异的贡献率范围为4.05%～12.61%,其中位于第6染色体RM225-RM204区间的qGC 6和位于第9染色体RM219-RM3700区间的qGC 9对表型变异的贡献率分别为12.61%和10.85%。共检测到与水稻发芽率相对碱害率相关的QTL 6个,对表型变异的贡献率为4.82%～28.07%,其中位于第2染色体RM29-RM221区间的qRGC 2、位于第6染色体RM225-RM204区间的qRGC 6 1、位于第9染色体RM219-RM3700区间的qRGC 9和位于第12染色体RM260-RM3226区间的qRGC 12对表型变异的贡献率较大,分别为28.07％、15.35％、15.61％和18.91％,为主效QTL,但其相应的区间距离均较远,需要进一步深入研究。所检测的QTL增效等位基因主要表现为部分显性和超显性。 相似文献
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Jongsung LEE Sangil SUH Ran CHOI Changbaig HYUN 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1677-1680
This study evaluated anesthesia quality, degree of analgesia and cardiorespiratory
parameters after intramuscular (IM) injection of a combination of butorphanol (0.1 mg/kg),
medetomidine (10 µg/kg) and alfaxalone (1.5 mg/kg) in ten healthy adult
Beagle dogs. Rectal temperature (T), heart rate (HR), respiratory rate
(fR), arterial pressure, arterial blood gases and M-mode
echocardiographic left ventricular (LV) indices were measured before drug administration
and every 10 min thereafter until extubation. Mean duration of anesthesia, recovery and
analgesia were 89 ± 17, 6 ± 1 and 80 ± 12 min. HR, fR, partial
pressure of arterial CO2 and O2, arterial pressure, and LV
contractility were significantly altered during anesthesia. IM administration of the drug
combination provided acceptable anesthesia, but produced substantial cardiorespiratory
suppression. 相似文献
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CCL2 induces neural stem cell proliferation and neuronal differentiation in
Niemann-Pick type C mice
Yu Ri HONG Hyun LEE Min Hee PARK Jong Kil LEE Ju Youn LEE Hwa Deok SUH Min Seock JEONG Jae-Sung BAE Hee Kyung JIN 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(6):693-699
Niemann-Pick type C disease (NP-C) is a rare and ultimately fatal lysosomal storage
disorder with variable neurologic symptoms. Loss of neuronal function and neuronal cell
death occur in the NP-C brain, similar to the findings for other neurodegenerative
diseases. Targeting of neuronal cells in the brain therefore represents a potential
clinical intervention strategy to reduce the rate of disease progression and improve the
quality of life. We previously reported that bone marrow stem cells show a neurogenic
effect through CCL2 (also known as monocyte chemoattractant protein-1, MCP-1) secretion in
the brains of NP-C mice. However, the direct effect of CCL2 on neurogenesis has not been
ascertained. Here, to define neurogenic effects of CCL2 in NP-C, we applied human
recombinant CCL2 to neural stem cells (NSCs) derived from NP-C mice. CCL2-treated NSCs
showed significantly increased capacity for self-renewal, proliferation and neuronal
differentiation. Similar results were observed in the subventricular zone of NP-C mice
after CCL2 treatment. Furthermore, infusion of CCL2 into the NP-C mouse brain resulted in
reduction of neuroinflammation. Taken together, our results demonstrate that CCL2 is a
potential new therapeutic agent for NP-C. 相似文献
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Sileshi BELEW Jin-Yoon KIM Md.Akil HOSSAIN Ji-Yong PARK Seung-Jin LEE Yong-Soo PARK Joo-Won SUH Jong-Choon KIM Seung-Chun PARK 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(3):327-329
Pharmacokinetic (PK) parameters of marbofloxacin (MRFX) in Korean cattle, Hanwoo, were
determined following its intravenous (i.v.) or intramuscular (i.m.) administration at a
dose of 2 mg/kg. Area under the curve (AUC0–24 hr), half-life (t1/2)
and total body clearance (CLB) of i.v. MRFX were 6.87
hr∙µg/ml, 2.44 hr and 0.29 l/kg∙hr,
respectively, and the corresponding values for i.m. administration of MRFX were 5.07
hr∙µg/ml, 2.44 hr and 0.39 l/kg∙hr.
The suggested optimal doses of MRFX in Hanwoo cattle, calculated by integration of PK data
obtained in the present study and previously reported minimum inhibitory concentration
(MIC) for MRFX against susceptible (MIC ≤1 µg/ml) and
intermediate (MIC ≤2 µg/ml) pathogenic bacteria, were
2.1 and 4.2 mg/kg/day by i.v. route and 3.9 and 7.8 mg/kg/day by i.m. route. 相似文献
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碱胁迫下粳稻幼苗前期耐碱性的数量性状基因座检测 总被引：7，自引：0，他引：7
以粳粳交“高产106/长白9号”F2:3代200个家系为作图群体, 在0.15% Na2CO3溶液的碱性胁迫下, 进行了水稻耐碱性鉴定, 并以SSR标记构建的分子连锁图谱为基础, 对水稻幼苗前期的根数、根长和苗高及其相对碱害率进行了数量性状基因座(QTLs)的检测。结果表明, 上述性状在F3家系群中均表现为具有1~2个峰的连续分布, 认为由主效基因和微效基因共同控制的数量性状。共检测到与碱胁迫下幼苗前期根数、根长和苗高及其相对碱害率相关的QTL 26个, 分布于第1、5、6、7、8、9和11染色体上。其中, 碱胁迫下与根数相关的QTL 4个, qRN6-1和qRN11对表型变异的解释率较大, 分别为29.91%和13.42%;与根数相对碱害率相关的QTL 5个, qRRN11-2对表型变异的解释率较大, 为23.86%;与根长相关的QTL 6个, qRRL11-2对表型变异的解释率较大, 为21.06%;与根长相对碱害率相关的QTL 2个, 但对表型变异的解释率均较低;与苗高相关的QTL 5个, qSH1和qSH11-2对表型变异的解释率较大, 分别为15.81%和16.53%;与苗高相对碱害率相关的QTL 4个, qRSH5和qRSH6-2对表型变异的解释率分别为29.89%和34.63%。而这些解释率较大的QTL所处的标记区间距离, 除qRN6-1相对较小(19.0 cM)外, 其余QTL的标记区间距离均大于26.3 cM, 需作进一步的精细定位。在所检测到的QTL中, 13个QTL的增效等位基因均来自耐碱亲本长白9号, 而其余QTL的增效等位基因来自敏碱亲本高产106;基因的主要作用方式为超显性或部分显性。 相似文献
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