检索结果-南通市图书馆

Global warming related carbon dioxide abatement proposals

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 1993年第3期5卷 269-278页

作者： Jung Sik koh UN ESCAP Bangkok 10200 Thailand

The relationship between man-made CO2 emission and atmospheric CO2 concentration has been established. The factors that affect CO2 reduction allotment and the impacts on future energy demand and supply were discussed, in order to help energy policy makers both in developed countries and in developing countries for understanding the fundamental constraint on energy sector resulted from global warming related CO2 reduction, and hopefully in finding a common objective starting point to deal with global warming negotiation in energy sector, and to investigate the optimum stabilization goal and process acceptable to all sovereign countries that based on equity and applicability.

关键词： global wanning carbon dioxide abatement optimum CO2 stabilization.

Sliding Mode Controller Design for Inverted Pendulum Balancing Mobile Robot

在线全文

学校读者我要写书评

暂无评论

Sliding Mode Controller Design for Inverted Pendulum Balanci...

作者： SEUNGJIN koh 上海交通大学

学位级别：硕士

近年来,随着硬件和计算技术的发展,交通运输领域的机器人技术取得了令人瞩目的成就,其中,两轮平衡移动机器人（2WBMR）受到了广泛的关注,其特点在于可以实现类似人类的运动和平衡能力。2WBMR系统属于非最小相位的欠驱动系统,加之系统本... 详细信息

近年来,随着硬件和计算技术的发展,交通运输领域的机器人技术取得了令人瞩目的成就,其中,两轮平衡移动机器人（2WBMR）受到了广泛的关注,其特点在于可以实现类似人类的运动和平衡能力。2WBMR系统属于非最小相位的欠驱动系统,加之系统本身存在的不稳定和非线性,使其在定位和抗干扰控制等方面存在诸多挑战。本文尝试建立两轮平衡移动机器人的非线性模型,基于滑模控制（SMC）方法对两轮平衡移动机器人的定位和抗干扰控制问题进行研究。论文的主要研究内容和贡献概述如下。1.在MATLAB中采用Simulink工具建立了2WBMR非线性模型。首先采用不同的Simulink块构建了子系统的模型,然后将这些块组合起来形成2WBMR的非线性模型。该模型容易理解、易于适应大参数不确定性。2.提出了一种将滑模控制与最优线性二次调节器（LQR）相结合的控制策略。滑模控制器是一种非线性控制方法,能够保证被控系统的鲁棒性。本文在滑模控制器的基础上引入状态反馈,通过采用LQR方法,根据极点配置和二次型极小化等设计方法选择参数。论文在控制器的效果分析中对非线性2WMBR对象进行了线性化,但最终设计的控制器将应用于非线性2WBMR对象。为了克服传统滑模控制中出现的抖振,本文采用了一种新的类sigmoid函数趋近律。将该趋近律应用于2WBMR的输出调节,结果表明,采用LQR设计的SMC在定位方面优于普通的SMC控制方法和LQR单独控制的方法。3.进一步采用积分滑模控制（integral sliding mode control,ISMC）设计,实现了对传统滑模控制方法的扩展,用以提高2WBMR控制系统的抗干扰能力。对ISMC,采用系统的线性模型设计了控制律,并将其应用于非线性系统。本文使用ISMC、SMC和LQR对2WBMR非线性系统在阶跃干扰下的控制性能进行了评估。仿真结果显示,在抗干扰方面ISMC优于普通LQR方法,也优于与LQR相结合的SMC方法。4.针对2WBMR对象提出了一种基于线性矩阵不等式（linear matrix inequality,LMI）的SMC算法。将基于LMI的滑模控制器应用于非线性系统,发现整个系统的定位性能优于ISMC、SMC和LQR方法。尽管ISMC适用于阶跃扰动,但它不适用于正弦时变扰动;而基于LMI的滑模变结构在定位和抗干扰方面均表现出良好的性能。概括地说,本文利用Simulink建立了2WBMR的非线性模型,提出了三种设计方法。论文提出不同设计方法的目的是确定最合适的控制器。结果表明,基于LMI的滑模控制器是最合适的控制器,其次是ISMC,然后是带LQR的滑模控制器。

关键词：抗干扰非线性建模滑模控制积分滑模控制线性矩阵不等式两轮平衡移动机器人

Juxtacrine interaction of macrophages and bone marrow stromal cells induce interleukin-6 signals and promote cell migration

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Bone Research 2015年第2期3卷 100-111页

作者： Jia Chang Amy J koh Hernan Roca Laurie K McCauley Department of Periodontics and Oral Medicine University of Michigan School of Dentistry Department of Periodontology University of Florida College of Dentistry Department of Pathology University of Michigan Medical School

The bone marrow contains a heterogeneous milieu of cells, including macrophages, which are key cellular mediators for resolving infection and inflammation. Macrophages are most well known for their ability to phagocytose foreign bodies or apoptotic cells to maintain homeostasis; however, little is known about their function in the bone microenvironment. In the current study, we investigated the in vitro interaction of murine macrophages and bone marrow stromal cells （BMSCs）, with focus on the juxtacrine induction of IL-6 signaling and the resultant effect on BMSC migration and growth. The juxtacrine interaction of primary mouse macrophages and BMSCs activated IL-6 signaling in the co-cultures, which subsequently enhanced BMSC migration and increased BMSC numbers. BMSCs and macrophages harvested from IL-6 knockout mice revealed that IL-6 signaling was essential for enhancement of BMSC migration and increased BMSC numbers via juxtacrine interactions. BMSCs were the main contributor of IL-6 signaling~ and hence activation of the IL-6/ gp130/STAT3 pathway. Meanwhile, macrophage derived IL-6 remained important for the overall production of IL-6 protein in the co-cultures. Taken together, these findings show the function of macmphages as co-inducers of migration and growth of BMSCs, which could directly influence bone formation and turnover.

关键词： BMSCs IL bone STAT cell

Assessing the thermal stability of toolmarks casting materials through optical comparison microscopy,virtual comparison microscopy and quantitative similarity scores

在线全文

学校读者我要写书评

暂无评论

Forensic Sciences Research 2022年第4期7卷 782-789页

作者： Alaric C.W.koh Kai Yuan Yeoh Forensic Chemistry and Physics Laboratory Health Sciences AuthoritySingapore

Toolmarks,particularly those found on bulky,inaccessible or immovable items,can be recovered by *** allow for subsequent comparative examinations,the casting material,typically polysiloxanes or silicones,must be able to capture and preserve fine details within a toolmark *** study the stability of such details after exposure to heat,toolmark casts were heated at either 60°C for 2 h,or 90°C for 1 *** casts were subsequently compared to casts that had not been exposed to heat,using traditional optical comparison microscopy,as well as virtual comparison *** toolmark signatures were also extracted from the casts and compared pairwise to obtain quantitative similarity scores based on cross-correlation,consecutive matching striae and Mann-Whitney *** results show that the fine surface details captured on all four commercial toolmark casting materials tested herein remained stable after exposure to *** study shows that the above heating protocols are viable viral inactivation methods for toolmark casts that are potentially contaminated with human coronaviruses,such as *** findings also apply to other scenarios,such as for casts that were left in a vehicle parked under the sun.

关键词： Forensic sciences casts coronavirus comparison microscopy polysiloxane thermal stability toolmarks

Effect of modified fasting therapy on body weight, fat and muscle mass, and blood chemistry in patients with obesity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Traditional Chinese Medicine 2016年第1期36卷 57-62页

作者： koh-Woon Kim Mi-Yeon Song Seok-Hee Chung Won-Seok Chung Department of Korean Rehabilitation Medicine College of Korean Medicine Kyung Hee University

OBJECTIVE: The aim of this study was to investigate the effects and safety of modified fasting therapy using fermented medicinal herbs and exercise on body weight, fat and muscle mass, and blood chemistry in obese ***: Twenty-six patients participated in a14-day fast, during which they ingested a supplement made from fermented medicinal herbs and carbohydrates(intake: 400-600 kcal/d). The schedule included 7 prefasting relief days and 14 days of stepwise reintroduction of food. The patients also took part in an exercise program that incorporated Qigong, weight training, and walking exercises. The efficacy of treatments was observed by assessing body fat mass and muscle mass, and alanine aminotransferase(ALT), aspartate aminotransferase(AST),cholesterol, and triglycerides in each study *** symptoms or side effects were ***: Body weight and body fat mass both decreased significantly by(5.16 ± 0.95) and(3.89 ±0.79) kg(both P < 0.05), while muscle mass decreased by an average of(0.26 ± 0.22) kg, without statistical significance. ALT levels were significantly decreased(P < 0.05), while AST levels decreased without statistical significance(P = 0.052). The levels of total cholesterol and triglycerides were also significantly decreased(both P < 0.05). There were few adverse events except for mild dizziness, which did not affect everyday ***: These results suggest that modified fasting therapy using fermented medicinal herbs and exercise could be effective and safe on obese patients.

关键词： Obesity Fasting Houttuynia Cordata Saururus Chinensis Exercise Blood chemicalanalysis Medicine, Korean traditional

Synthesis and mesomorphic behavior of benzothiazole-based liquid crystals having terminal methoxyl group

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2009年第12期20卷 1449-1452页

作者： Sie Tiong Ha Teck Ming koh Siew Teng Ong Yasodha Sivasothy Department of Chemical Science Faculty of ScienceEngineering & TechnologyUniversiti Tunku Abdul RahmanJln UniversitiBandar Barat 31900 KamparPerakMalaysia Department of Science Faculty of Engineering & ScienceUniversiti Tunku Abdul RahmanJln Genting KlangSetapak 53300 Kuala LumpurMalaysia Chemistry Department Faculty of ScienceUniversiti Malaya 50603 Kuala LumpurMalaysia

A homologous series of benzothiazole derivatives, 6-methoxy-2-（4-alkanoyloxybenzylidenamino）benzothiazoles, were synthesized and characterized using FT-IR, ^1H and ^13C NMR, mass spectrometry and elemental analysis. Enantiotropic nematic phase was observed throughout the entire series. Smectic C phase only emerged from the decanoyloxy derivative onwards. The terminal methoxyl group and the ester linkage influenced the mesomorphic behavior of the present series.

关键词： Benzothiazole Schiff bases Nematic Smectic C Liquid crystal

Calcaneal osteochondroma masquerading as plantar fasciitis: An approach to plantar heel pain-A case report and literature review

在线全文

学校读者我要写书评

暂无评论

World Journal of Orthopedics 2019年第9期10卷 339-347页

作者： Don koh Yvonne Goh Nicholas Yeo Department of Orthopaedic Surgery Singapore General HospitalSingapore 169856Singapore NUS Yong Loo Lin School of Medicine NUHS Tower BlockSingapore 119228Singapore

BACKGROUND Heel pain is a common orthopaedic complaint,and if left untreated can be a source of chronic *** diagnosis can be challenging,owing to the complex anatomy and multiple pain generators present in the *** aim to share our clinical experience managing an unusual case of chronic heel pain secondary to *** SUMMARY A 41-year-old obese male who works as a porter presented with a long-standing history of left plantar heel *** was assessed to have point tenderness over the plantar insertion of the calcaneus as well as a positive Silfverski?ld *** was treated for plantar fasciitis and tight gastrocnemius but failed conservative therapies as well as surgical *** resonance imaging revealed the presence of a pedunculated bony protrusion over the plantar aspect of the *** decision was made for excision of the osteochondroma,and the patient has been pain-free *** Osteochondromas are rarely symptomatic in skeletally mature *** most are benign with a very low risk of malignant transformation,surgical excision can yield excellent results and significant pain relief in symptomatic patients.

关键词： Chronic heel pain Recalcitrant heel pain Osteochondroma Diagnostic challenge Case report

Construction of a hierarchical multiscale conducting network for enhanced thermoelectric response in organic PEDOT:PSS based nanocomposites

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materiomics 2021年第1期7卷 34-39页

作者： Yong Zhang Siqi Liu J.Justin koh Chaobin He Department of Materials Science and Engineering National University of Singapore9 Engineering Drive 1117575Singapore Institute of Materials Research and Engineering A*STAR(Agency for ScienceTechnology and Research)117602Singapore

Thermoelectric technology,which is characterized by the interconversion between heat and electricity,is demonstrated as an efficient and environmentally friendly route for thermal energy harvesting and solid-state cooling *** pursuit for high-performance room temperature thermoelectric materials is of significant ***,we proposed a design strategy to dramatically improve the thermoelectric response by constructing a hierarchical multiscale conductor network(AgNWs/CNT)in polymer matrix(PEDOT:PSS).At the optimized composition,the highest Seebeck coefficient and electrical conductivity of base treated ternary PEDOT:PSS/AgNWs/CNT composite are optimized to be 58.6μV K^(-1)and~1950 S ***,the power factor is thus calculated to be on the order of 670μV m^(-1)K^(-2),which is among one of the highest values compared with previous *** underlying mechanism is illustrated based on detailed structure,morphology and electron transport *** work affords a novel strategy for the future development of high-performance room temperature nanocomposite thermoelectrics.

关键词： PEDOT:PSS Thermoelectrics Energy harvesting Hierarchical structure Seebeck coefficient

CHANGING PERCEPTIONS OF CHINESE PRODUCTS BY AMERICAN CONSUMERS

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

管理工程学报 1989年第Z1期 52-56+64页

作者： James A.Brunner Anthony koh The University of Toledo The University of Toledo Ph.D. Ph.D.

One of the primary objectives of the People's Republic of China (PRC) is an expansion of its foreign trade. To contribute to this objective, it is essential that effective marketing strategies be developed incorporating all elements of the marketing mix, one of the most important being the Produts. Earlier studies indicate that consumers tend to stereotype Products by the country of origin and therefore assume that goods from that country are of similar quality even though they may be familiar with only a limited variety of that country's Products.

关键词： PRC 管理工程学产业工程学 CHANGING PERCEPTIONS OF CHINESE PRODUCTS BY AMERICAN CONSUMERS TOTAL 商品