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31.
A large class of visual servo controllers relies on an a priori obtained reference image, captured at the desired position and orientation (i.e., pose) of a camera, to yield control signals to regulate the camera from its current pose to a desired pose. In many applications, accessibility and economics of the operation may prohibit acquisition of such a reference image. This paper introduces a new visual servo control paradigm that enables control of the camera in the absence of reference image using a set of terminal constraints. Specifically, the desired pose is encoded using the angle of obliquity of the optical axis with respect to the object plane and its direction of arrival at the plane. A constrained convex optimization problem is formulated over a conic section defined by the terminal constraints to yield an error system for the control problem. Subsequently, this work introduces continuous terminal sliding mode visual servo controllers to regulate the camera to the desired pose. Lyapunov-based stability analysis guarantees that the origin is a finite-time-stable equilibrium of the system. Numerical simulation results are provided to verify the performance of the proposed visual servo controller.  相似文献   
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A dual S shaped micro strip antenna with a realistic feed is proposed for generation of tilted beam radiation pattern pertaining for beam steering applications. To achieve this, four feeding points are located at a distance of 5.6 mm from the antenna centre. These feeding points when excited one by one generate four tilted beams in four different space quadrants, thus yielding a beam steerable antenna. Importantly, since the proposed antenna is symmetrical in the structure, all the four tilted beams have the same radiation pattern characteristics. A further enhancement of the antenna bandwidth is also achieved using 100-μm capacitive coupling between the feed and the antenna strip.  相似文献   
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During post-analytical phase, critical value notification to responsible caregiver in a timely manner has potential to improve patient safety which requires cooperative efforts between laboratory personnel and caregivers. It is widely accepted by hospital accreditors that ineffective notification can lead to diagnostic errors that potentially harm patients and are preventable. The objective of the study was to assess the variables affecting critical value notification, their role in affecting it’s quality and approaches to improve it. In the present study 1,187 critical values were analysed in the Clinical Chemistry Laboratory catering to tertiary care hospital for neuropsychiatric diseases. During 25 months of study period, we evaluated critical value notification with respect to clinical care area, caregiver to whom it was notified and timeliness of notification. During the study period (25 months), the laboratory obtained 1,279 critical values in clinical chemistry. The analytes most commonly notified were sodium and potassium (20.97 & 20.8 % of total critical results). Analysis of critical value notification versus area of care showed that critical value notification was high in ICU and emergency area followed by inpatients and 64.61 % critical values were notified between 30 and 120 min after receiving the samples. It was found that failure to notify the responsible caregiver in timely manner represent an important patient safety issue and may lead to diagnostic errors. The major area of concern are notification of critical value for outpatient samples, incompleteness of test requisition forms regarding illegible writing, lack of information of treating physician and location of test ordering and difficulty in contacting the responsible caregiver.  相似文献   
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We explored teachers’ views and students’ experiences of going beyond the syllabus in Advanced (A) level Mathematics. Questionnaires were sent to teachers and students in a sample of 200 schools and colleges. Teachers were asked about the necessity, importance and benefits of additional teaching. Students were asked about the extra activities they undertook. Forty-seven teacher questionnaires and 299 student questionnaires were completed. Over half of the students claimed to undertake at least some extra activities. Although a few teachers thought teaching beyond the syllabus was unimportant and unnecessary, over 70% felt it should be undertaken if time allowed. Teaching efficacy was measured by comparing each teacher’s students’ Mathematics results with those students’ results in other A level subjects. Significantly more teachers with relatively high Mathematics results than with relatively low results believed teaching beyond the syllabus strengthens and expands students’ existing knowledge and adds interest to the course.  相似文献   
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Curcuma longa commonly known as tumeric is traditionally used as a spice in Indian food. A wide range of biological activities e.g. anticancer, antimicrobial, antiinflammatory and free radical scavenging activity of the plant suggests a logical basis for its traditional use in foodstuff. Various phytothreapeutic uses ofCurcuma longa have been reviewed.  相似文献   
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With disasters on the rise, counselors need to increase their cultural awareness, knowledge, and skills to work with affected communities. This study reports outcomes of a four-week immersion experience in southern Africa with six counselor-trainees. Data sources for this qualitative study were: daily journals and demographic forms. Outcomes suggest that sustained contact with community residents and daily supervision experiences served to improve cultural awareness. Recommendations include pushing through students?? resistance using a non-linear dynamic model of transformation.  相似文献   
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Total acetylcholinesterase activity (AChE) was estimated in CSF and serum of 163 cases, comprising of 64 cases of Tuberculous meningitis (TBM), 60 cases of pyogenic meningitis (PM) and 30 control in the paediatric age group. Mean CSF-AChE levels were 7.94±0.38, 9.06±0.16 and 9.80±0.30 unit/ml (Mean±S.E.) in Control, TBM and PM respectively. The respective serum AChE levels were 2.65±0.13, 3.18±0.07 and 3.93±0 0.035 units/ml. The ratio of CSF/serum-AChE in three groups were 3.09±0.137 (Mean±S.E.), 2.88±0.087, 2.98±0.092 in control, TBM and PM respectively. The values in both CSF as well as in serum in patient with TBM and in PM were significantly higher as compared to controls. However, the differences between the mean CSF-AChE and serum-AChE levels and CSF-AChE/serum-AChE were insignificant. Thus, though AChE levels are raised in meningitis, they are not helpful in differentiating TBM from PM.  相似文献   
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