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On the Use of Quaternions, Dual Quaternions, and Double Quaternions For Freeform Motion Synthesis

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On the Use of Quaternions, Dual Quaternions, and Double Quat...

Cleaning properties of dry adhesives

第十四届全国机构学学术研讨会暨第二届海峡两岸机构学学术交流会

作者： A．Varshney j.menon State University of New York Stony Brook New YorkUSA IBM T.j.Watson Research Center Yorktown Heights New YorkUSA

Recently,there has been considerable effort to bring together quaternion-based representations of spatial displacements with curve design techniques in Computer Aided Geometric Design (CAGD) to develop methods for synthesizing freeform Cartesian *** methods have a wide range of applications from computer graphics, Cartesian motion planning for robot manipulators to task specification and motion approximation for spatial mechanism *** paper compares the use of quaternions,dual quaternions,and double quaternions for freeform motion synthesis in a CAD environment.

关键词： quaternions CAGD motion animation

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Science China(Technological Sciences) 2010年第11期53卷 2942-2946页

作者： j. P. DíAZ TéLLEZ D. SAMEOTO C. menon MENRVA Group School of Engineering Science Simon Fraser University Department of Mechanical Engineering University of Alberta

In this paper we present a study into the cleaning properties of synthetic dry adhesives. We have manufactured the adhesive micro-fibres through a low-cost, high yield fabrication method using Sylgard 184 Polydimethylsiloxane (PDMS) as the structural material. We deliberately contaminated the adhesive samples with different sized particles in the micro and macro scales and tested different cleaning methods for their efficacy with respect to each particle size. We investigated different cleaning methods, which included the use of wax moulding, vibration and pressure sensitive adhesives. For adhesion testing we used a custom system with a linear stage and a force sensor indenting a hemispherical probe into the adhesive surface and measuring the pull-off force. To characterize the cleaning efficacy we visually inspected each sample in a microscope and weighed the samples with a microgram-accuracy analytical balance. Results showed that the moulding method induced adhesion recovery in a greater percentage than the other cleaning methods and even helped with the recovery of collapsed posts in some cases. On the other hand pressure sensitive adhesives seem to have the upper hand with regards to certain particle sizes that can potentially pose problems with the moulding method.

关键词： biomimetic dry adhesive PDMS self-cleaning gecko climbing

Learning-based joint UAV trajectory and power allocation optimization for secure IoT networks

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Digital Communications and Networks 2022年第4期8卷 415-421页

作者： Dan Deng Xingwang Li Varun menon Md jalil Piran Hui Chen Mian Ahmad jan School of Information Engineering Guangzhou Panyu PolytechnicGuangzhou410630China School of Physics and Electronic Information Engineering Henan Polytechnic UniversityJiaozuo454150China Department of Computer Science and Engineering SCMS School of Engineering and TechnologyIndia Department of Computer Science and Engineering Sejong UniversitySouth Korea Department of Computer Science Abdul Wali Khan University MardanPakistan

Non-Orthogonal Multiplex Access(NOMA)can be deployed in Unmanned Aerial Vehicle(UAV)networks to improve spectrum *** to the broadcasting feature of NOMA-UAV networks,it is essential to focus on the security of the wireless *** paper focuses on maximizing the secrecy sum rate under the constraint of the achievable rate of the legitimate *** tackle the non-convexity optimization problem,a reinforcement learning-based alternative optimization algorithm is ***,with the help of successive convex approximations,the optimal power allocation scheme with a given UAV trajectory is obtained by using convex optimization ***,through plenty of explorations of the wireless environment,the Q-learning networks approach the optimal location transition strategy of the UAV,even without the wireless channel state information.

关键词： Unmanned aerial vehicle(UAV) NOMA Reinforcement learning Secure communications Deep Q-learning

The Strengths and Difficulties Questionnaire： A Pilot Study on the Reliability and Validity of the Self-report Version to Measure the Mental Health of Zambian Adolescents

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journal of Health Science 2014年第3期2卷 127-134页

作者： j. Anitha menon Department of Psychology University of Zambia Lusaka 38301 Zambia

The study had the objective of exploring the feasibility of using the self-report SDQ-Y （youth version of strengths and difficulties questionnaire） to assess the emotional and behavioural well being of adolescents in Zambia. This was a cross sectional study of Lusaka school children （n = 420） aged 11-15 years using the self-report SDQ-Y and a demographic questionnaire. It was found that compared to a UK normative sample, Zambian adolescents were almost twice as likely to have total difficulties scores in the abnormal range （O.R. 1.9）. It was found that there was a significant difference in the total SDQ scores （Z = -2.67, P = 0.008） with children reporting health problems having significantly higher scores. Children reporting health problems also had significantly more emotional problems （Z = -2.78, P = 0.005）. There was a trend for children with health problems to score higher on the hyperactivity scale （Z = -1.9 P = 0.053）. The internal consistency of SDQ subscales ranged from low to moderate. It can be concluded that SDQ is a useful instrument for use with Zambian adolescents, in particular, the total difficulties score and the emotional difficulties score performed well in this sample and could potentially be used to screen for mental health problems or to examine the impact of interventions.

关键词： Strengths and difficulty questionnaire adolescents Zambia reliability validity.

Bone mineral density and disorders of mineral metabolism in chronic liver disease

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World journal of Gastroenterology 2009年第28期15卷 3516-3522页

作者： joe George Hosahithlu K Ganesh Shrikrishna Acharya Tushar R Bandgar Vyankatesh Shivane Anjana Karvat Shobna j Bhatia Samir Shah Padmavathy S menon Nalini Shah Department of Endocrinology Seth G.S. Medical College and KEM Hospital Department of Gastroenterology Seth G.S Medical College and KEM Hospital Department of Gastroenterology Jaslok Hospital

AIM： To estimate the prevalence and identify the risk factors for metabolic bone disease in patients with cirrhosis. METHODS： The study was performed on 72 Indian patients with cirrhosis （63 male, 9 female; aged 〈 50 years）. Etiology of cirrhosis was alcoholism （n = 37）, hepatitis B （n = 25） and hepatitis C （n = 10）. Twenty-three patients belonged to Child class A, while 39 were in class B and 10 in class C. Secondary causes for metabolic bone disease and osteoporosis were ruled out. Sunlight exposure, physical activity and dietary constituents were calculated. Complete metabolic profiles were derived, and bone mineral density （BMD） was measured using dual energy X ray absorptiometry. Low BMD was defined as a Z score below -2. RESULTS： Low BMD was found in 68% of patients. Lumbar spine was the most frequently and severely affected site. Risk factors for low BMD included low physical activity, decreased sunlight exposure, and low lean body mass. Calcium intake was adequate, with unfavorable calcium： protein ratio and calcium： phosphorus ratio. Vitamin D deficiency was highly prevalent （92%）. There was a high incidence of hypogonadism （41%）. Serum estradiol level was elevated significantly in patients with normal BMD. Insulin-like growth factor （IGF） 1 and IGF binding protein 3 levels were below the age-related normal range in both groups. IGF-1 was significantly lower in patients with low BMD. Serum osteocalcin level was low （68%） and urinary deoxypyridinoline to creatinine ratio was high （79%）, which demonstrated low bone formation with high resorption. CONCLUSION： Patients with cirrhosis have low BMD. Contributory factors are reduced physical activity, low lean body mass, vitamin D deficiency and hypogonadism and low IGF-1 level.

关键词： Bone mineral density Liver disease Chronic disease Cirrhosis Bone mineral metabolism Hepatic osteodystrophy

Factors Associated with Women＇s Attitude towards Spousal Abuse： The Case of Zambia

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journal of Health Science 2015年第5期3卷 217-224页

作者： Kusanthan Thankian Sidney O. C. Mwaba Anitha j. menon Department of Psychology School of Humanities and Social Sciences University of Zambia Zambia

Gender based violence （GBV） is a worldwide scourge and spousal battering has been found to be a common form of GBV. The objective of this paper was to examine the attitudes of women towards spousal battering and to assess the association between women＇s attitudes and the likelihood of being abused. The paper utilizes secondary data from the 2007 Zambia Demographic Health Survey （ZDHS）. Results show that the younger women were more likely to justify wife beating when compared to older women （P 〈 0.05）. Women from urban areas （68%） with middle income background （71%） were more likely to agree that wife beating is justified compared to rural women （56%） and women with a higher income background （51%）. Women who had attained secondary level of education were 1.3 times more likely to report that wife beating was justified compared to those from higher levels of education. Women whose husbands drunk alcohol were 1.2 times more likely to report that wife beating was justified compared to those women whose husbands never drunk alcohol. The results from the analysis suggests that age, marital duration, place of residence, wealth index, partner＇s wife and husband＇s educational level, number of children and husband＇s alcohol consumption contributed to justification of spousal battering.

关键词： Domestic violence wife beating spousal battering wife justification.

视力损害中的复杂视幻觉:一种结构性病史采集方法

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世界核心医学期刊文摘(眼科学分册) 2006年第1期 22-23页

作者： menon G.j. 王大江 UnitedKingdom Royal Eye Infirmary Apsley Road Plymouth PL4 6PL

Objective: To study complex visual hallucinations in visually impaired individuals. Methods: A prospective comparative study involving structured history taking and cognitive assessment in 48 consecutive visually impaired individuals with best-corrected visual acuity of 20/200 or worse and an agematched cohort of 48 consecutive patients with visual acuity of 20/40 or better in at least 1 eye. Results: Thirty visually impaired subjects (63% ) experienced hallucinations, unrelated to specific ocular pathology. None volunteered the symptom; 2 admitted hallucinations on nonleading questioning and 28 on direct questioning. All displayed insight into the unreality of their hallucinations, although 18 (60% ) achieved this after initial deception. Seventeen (57% ) expressed concern; 7 (23% ) experienced disturbing images. Nineteen (63% ) feared being labeled as insane were they to admit to hallucinations, while 10 (33% ) were fearful of impending insanity. Sixteen (94% ) of 17 concerned patients derived comfort from sympathetic reassurance that their hallucinations did not represent sinister pathology. In contrast, none of the individuals with normal vision experienced any hallucinations (P < .001). Cognition was intact in all groups. Conclusions: Complex visual hallucinations with insight commonly occur in visually impaired, cognitively intact individuals due to acquired visual impairment and are unrelated to chronological age. Hallucinatory experiences are almost invariably admitted to only on direct questioning, due to fears of being considered insane. Although generally pleasant, hallucinations may cause distress, because of content or implications of the hallucinatory activity. Sympathetic explanation affords significant emotional relief.

关键词：视幻觉患者视力损害病史采集结构性