Transfer functions of the 2-phase servomotor

One of the most common electromechanical positioning devices for low-power applications is the 2-phase servomotor, several different . constructional forms being available. When used in a control application, various transfer functions of the machine are important and these have been investigated by previous workers using analyses of varying validity. For example, in early studies, it was common to regard the speed-torque characteristics of the machine as straight lines, and also to neglect the electrical energy storage elements in comparison with those of the mechanical system. Quite sophisticated mathematical studies using, for example, symmetrical components, were based on these assumptions, but the results obtained are obviously highly suspect in view of the doubtful basis from which they are established. Experimental verification of the results of the analyses were confined to steady-state. measurements, attention being devoted to establishing an equivalent circuit to provide steady-state characteristics. Recently, with the increasing use of powerful mathematical tools in engineering situations, several workers have attempted to obtain direct solutions of the nonlinear equations characterising the -operation of the servomotor. Thus, simulation and state transition methods, involving a step-by-step numerical solution, have attracted considerable interest. Although these approaches may provide useful numerical answers, they do not help in forming any understanding of the main factors affecting the transient performance of the machine. A recent paper used the complex convolution approach to provide analytical transfer functions, but unfortunately this paper contains a fundamental error which completely invalidates the work. The same formal approach is followed in this thesis, with the complex convolution technique being used to find time-domain expressions for the variations in speed which follow step changes in either the torque or the magnitude or phase of the control-winding voltage. As in the previous work, attention is confined to the practically important range of speed much lower than synchronous speed, Results obtained from the analysis are compared with experimentally obtained results and with results provided by earlier analyses, and an assessment is made of the usefulness and limitations of the various techniques

Gamma glutamyl transferase and lactate dehydrogenase as biochemical markers of severity of preeclampsia among Sudanese pregnant women

Background: Preeclampsia is a disorder of widespread vascular endothelial malfunction and vasospasm that occurs after 20 weeks' gestation and can present as late as 4-6 weeks post-partum. Pre-eclampsia is a syndrome with multiple aetiologies which has made it difficult to develop adequate screening tests and treatments. Objective of this study to assess the level of gamma glutamyl transferase and lactate dehydrogenase as biochemical markers of severity of preeclampsia in Sudanese pregnant women.Methods: This is a case control hospitalize base study. The study was conducted in preeclamptic pregnant women in Omdurman maternity hospital and medical military hospital in Khartoum state. In this study glutamyl transferase and lactate de-hydrogenase was estimation in 100 Sudanese pregnant women by spectrophotometer method, 50 of them were diagnosed with preeclampsia 27 from this is severe preeclampsia and 23 is mild preeclampsia was matched in aged. Serum samples of all the cases were assayed for GGT and LDH. The data was recorded and analyzed using statistical package for social sciences (SPS –version 16) on programmed computer. The mean standard deviations of variable were calculated for both the test group and the control group and P value for comparison was obtained.Results: The mean values of plasma gamma glutamyl transferase in mild and severe preeclamptic pregnant women were insignificant difference when compared to control P value (0.346 - 0.089) respectively. The mean values of plasma lactate dehydrogenase in mild and severe preeclamptic pregnant women were significant increase when compared to control P value (0.008 - 0.001) respectively.Conclusions: The levels of LDH is raised in Sudanese pregnant women with hypertensive also can be useful biochemical marker that reflects the severity of and the occurrence of complications of pre-eclampsia. GGT levels were normal in Sudanese pregnant women with hypertensive preeclampsia

VIDEO LOCALIZATION USING ARRAY OF MICORPHONES

Object localization helps to improve the surveillance system and provide extra information from the camera. In this study DCS 5220 PT camera and array of microphones are used to achieve camera localization based on audio inputs, the system consists of microphones, multiplexing circuit, computer and PT camera. The results obtains clearly demonstrates that this techniques is usable for videodiscussion applications. The localization algorithm is based on comparing the amplitude level of the signals from all microphones and then selects the one with higher amplitude, strong noise presence is one of the limitations of this techniques, however the type of noise add can be clearly identified in the frequency spectrum, and for this reason signals are compared in their frequency spectrum after the noise is been trimmed off. The DCS 5220 PT camera is IP camera manufactured by Dlink, it can pan and tilt by using URL command; to utilize the camera a network is been created by using DR 300 wireless router with data rate up to 54 Mbps and can accommodate up to 4 network elements. The system is been developed for closed room localization but it can also be extended to outdoor applications by using suitable sensors and suitable cameras, in video discussions the system can be used in conferences and in parliament halls where such a system can be used as an automatic cameraman

3D VISUAL TRACKING USING A SINGLE CAMERA

automated surveillance and motion based recognition. 3D tracking address the localization of moving target is the 3D space. Therefore, 3D tracking requires 3D measurement of the moving object which cannot be obtained from 2D cameras. Existing 3D tracking systems use multiple cameras for computing the depth of field and it is only used in research laboratories. Millions of surveillance cameras are installed worldwide and all of them capture 2D images. Therefore, 3D tracking cannot be performed with these cameras unless multiple cameras are installed at each location in order to compute the depth. This means installing millions of new cameras which is not a feasible solution. This work introduces a novel depth estimation method from a single 2D image using triangulation. This method computes the absolute depth of field for any object in the scene with high accuracy and short computational time. The developed method is used for performing 3D visual tracking using a single camera by providing the depth of field and ground coordinates of the moving object for each frame accurately and efficiently. Therefore, this technique can help in transforming existing 2D tracking and 2D video analytics into 3D without incurring additional costs. This makes video surveillance more efficient and increases its usage in human life. The proposed methodology uses background subtraction process for detecting a moving object in the image. Then, the newly developed depth estimation method is used for computing the 3D measurement of the moving target. Finally, the unscented Kalman filter is used for tracking the moving object given the 3D measurement obtained by the triangulation method. This system has been test and validated using several video sequences and it shows good performance in term of accuracy and computational complexity

A Novel Technique for Anterior Vaginal Wall Prolapse Repair: Anterior Vaginal Wall Darn

Aim. The aim of this study is to introduce a new technique, anterior vaginal wall darn (AVWD), which has not been used before to repair the anterior vaginal wall prolapse, a common problem among women. Materials and Methods. Forty-five women suffering from anterior vaginal wall prolapse were operated on with a new technique. The anterior vaginal wall was detached by sharp and blunt dissection via an incision beginning from the 1 cm proximal aspect of the external meatus extending to the vaginal apex, and the space between the tissues that attach the lateral walls of the vagina to the arcus tendineus fascia pelvis (ATFP) was then darned. Preoperation and early postoperation evaluations of the patients were conducted and summarized. Results. Data were collected six months after operation. Cough stress test (CST), Pelvic Organ Prolapse Quantification (POP-Q) evaluation, Incontinence Impact Questionnaire (IIQ-7), and Urogenital Distress Inventory (UDI-6) scores indicated recovery. According to the early postoperation results, all patients were satisfied with the operation. No vaginal mucosal erosion or any other complications were detected. Conclusion. In this initial series, our short-term results suggested that patients with grade II-III anterior vaginal wall prolapsus might be treated successfully with the AVWD method

NUTRITION ATTITUDES AND INFORMATION LEVELS OF FOOTBALL REFEREES

This study aims at revealing the changes in nutrition attitude and knowledge levels of football referees. 130 referees actively serving as Candidate, Provincial and Regional Referees in Izmir, Konya, Aksaray and Niğde provinces constituted the sample group of the study. The personal information form was used in obtaining the socio-demographic information and the nutrition knowledge and attitude scale developed by Ertürk (2010) was used in determination of the nutrition attitude and knowledge. The variance and homogeneity of the data were tested, "Independent Samples t Test" was used for binary comparisons, "One Way Anova" for differences between groups in multiple comparisons, and "Tukey" test for the determination of variation sources. The nutritional attitudes of the provincial and district referees were higher than those of the candidate referees and the nutritional information of the candidate referees were higher than the provincial and district referees and this change was statistically found to be significant (P <0.05). While no change due to the gender factor was observed, nutrition information of the referees received nutrition lessons was found to be higher than the referees who did not, and this change was statistically found to be significant (P <0.05). No difference was found in nutritional attitudes and knowledge of the referees depending on factors such as age, income, sibling, years of service, and level of education. As a result, it can be said that candidate referees who have just started their duties have more nutrition knowledge than provincial and district referees, and provincial and district referees have better nutrition attitudes than candidate referees. Football referees are thought to be an important issue in renewing their nutritional attitudes and knowledge in order to improve their performance and quality of life.  Article visualizations

Saving the fundaments: impact of a military coup on the Sudan health system

Military coups are not uncommon occurrences, particularly in developing nations where political systems might be less firmly entrenched or still evolving. Developments of this nature can often have profound implications for the affected nation’s healthcare systems, both in the immediate aftermath and over the longer term. This paper narrates some notable consequences of political instability on the national health system, particularly placing them in the context of the military coup in October 2021 – emphasizing the context behind the political turbulence, its acute and direct consequences, and the possible long-term legacies of political shocks on the already overwhelmed health system. As a descriptive piece, this narrative does not only look at the impact of the military coup on hospitals, but further considers the different dimensions of the healthcare system as defined by the WHO, therefore reflecting the wider implications on health funding from multi-laterals, service delivery, human resource availability, and medical and vaccine supply chains in Sudan

Saving the Fundaments: Impact of a Military Coup on the Sudan Health System

Military coups are not uncommon occurrences, particularly in developing nations where political systems might be less firmly entrenched or still evolving. Developments of this nature can often have profound implications for the affected nation’s healthcare systems, both in the immediate aftermath and over the longer term. This paper narrates some notable consequences of political instability on the national health system, particularly placing them in the context of the military coup in October 2021 – emphasizing the context behind the political turbulence, its acute and direct consequences, and the possible long-term legacies of political shocks on the already overwhelmed health system. As a descriptive piece, this narrative does not only look at the impact of the military coup on hospitals, but considers the implications for the healthcare system as defined by the WHO, with particular emphasis on the impact of the coup on health funding from multi-laterals, service delivery, human resource availability, and supply chains in Sudan

The Impact of Entrepreneurial Characteristics on Entrepreneurial Intention of Sudanese and Omani University Students

This study aims to identify the level of availability of entrepreneurial characteristics among undergraduate students in some universities of Sudan and Oman, and test whether these characteristics have a significant impact on the entrepreneurial intention of these students. The study also intends to make comparison between the attitudes of students in Sudan and Oman towards establishing their businesses (self-employment). The sample of the study (n = 574) consists of students from University of Bahri, Sudan International University, and Dhofar University. In order to achieve these objectives, the study adopted the descriptive and analytical approach and used the questionnaire as a tool for collecting primary. The findings reveal that, there is a statistically significant impact of the entrepreneurial characteristics among undergraduate students (need for achievement, self-efficacy and locus of control) on their entrepreneurial intention. The study also found that there are statistically significant differences in the views of the respondents according their universities, concerning the locus of control and entrepreneurial intention. The analysis showed that locus of control among students of Dhofar University and Sudan International University was higher than that of University of Bahri students. Furthermore, it was found that the entrepreneurial intention among students of Dhofar University was higher than that of Sudan International University & University of Bahri student

Obtained Carbon Nano-onions from Underwater Arc Discharge Without the Complex Purification Procedures

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