649 research outputs found
Radar High Resolution Range & Micro-Doppler Analysis of Human Motions
In radar imaging it is well known that relative motion or deformation of parts of illuminated objects induce additional features in the Doppler frequency spectra. These features are called micro-Doppler effect and appear as sidebands around the central Doppler frequency. They can provide valuable information about the structure of the moving parts and may be used for identification purposes [1]. Previous papers have mostly focused on ID micro-Doppler analysis [2-4]. In this paper, we propose to emphasize the analysis of such "non stationary targets" using a 2D imaging space, using both the micro-Doppler and a high range resolution analysis. As in 2D-ISAR imaging, range separation enables us to better discriminate the various effects caused by the time varying reflectors. We will focus our study on human motion. We will see how micro-Doppler signature can be used to extract information on pedestrians gait. We will show examples on simulated and experimental data
Impact of Applying of Ansoff Model on Marketing Performance for Saudi Foodstuff Companies
This study aims to determine the impact of Ansoff model application on marketing performance on Saudi foodstuff companies. To achieve the objectives of the study, a questionnaire was developed and distributed. The study population consists of all Saudi Food Companies employees, and convenience sample was selected 150 questionnaire were distributed, 110 were recalled which representing (73%) of the sample. The study finds that there is a strong impact of Applying Ansoff Model (market penetration strategy, product development strategy, market development strategy, diversification strategy) on marketing performance in Saudi Food Companies. The study recommended some recommendations which enable the decision-makers to use the strategies of Ansoff Model in effective way, which it helping Saudi Food Companies to increase the levels of marketing performance and to achieve its objectives, as survival, growth, achieve benefits and profits. Keywords: Ansoff Model, Marketing Performance, Food Companies, Saudi Arabia
Performance Evaluation of a Conventional Solar Still with Different Types and layouts of Wick Materials
Solar distillation is regarded by many investigators as one of the important methods of utilizing solar energy to solve water scarcity problems. A solar still is a simple device which can be effectively used to convert saline water into fresh water. The enhancement of solar stills performance and improving their production capacity of distilled water are the main goals of the investigators in recent years. In this research, three identical conventional basin type solar stills were designed and constructed in order to experimentally investigate the affect of using different wick materials in two different layout arrangements. The first solar still was used as a reference still for comparison. The second solar still was used for uniformly spreading the wick material sheets in the saline water. In this case, the wick materials sheets were completely immersed in the saline water covering the total still basin area. The third solar still had a specially designed set up of steel mesh wires. In this case, the wick materials were partially immersed in the saline. The net basin horizontal effective area of each solar still was 1 m², and the glass cover's tilted angle was fixed at 32.5º. Five types of wick materials in the form of material sheets were used. They were light black cotton fabric, light jute fabric, black velvet fabric, black sheer mesh fabric, and a 4 mm thick sponge sheet. Spreading the wick material sheet to cover the basin area had the effect of preventing the sunrays from reaching the still basin and consequently absorbed by the saline water and the wick material resulting in enhancing the yields of solar stills. The aim of adding mesh wire layout arrangement is to have the additional effect of increase the surface area of evaporation relaying on capillary effect to raise the saline water to the non-immersed part of the materials. It has been found that the solar still with only wick materials and no special arrangement performed much better than the other two solar stills. In both layout arrangements, it has been found that the light black cotton fabric was the most effective material in enhancing the still productivity in with 36.9% and 26.3% respectively. The sponge sheet was found the less effective material in enhancing the still productivity with 11.5% and 9.9% respectively. Keywords: Productivity; Solar stills; Water desalination; Wick materials; Wire mes
Moderating Role of Psychological Ownership between Authentic Leadership and Sports Team Performance: Mediating Effect of Sports Training
This study examines the mediating influence of sports training between authentic leadership (AL) and sports team performance (STP) in the setting of Saudi Arabia, with the moderating role of psychological ownership (PO). This study employs a cross-sectional survey design to obtain data from 300 members of sports teams. The results indicate that AL significantly and positively affects STP and that sports training mainly mediates this relationship. In addition, the data indicate that PO moderates the relationship between AL and athletic performance, such that the association is stronger for team members with a strong feeling of PO. These findings have significant implications for Saudi Arabian organizations seeking to improve the performance of their sports teams. While adopting the study's conclusions, it is recommended that employers engage in AL development, give frequent athletic training chances, promote a sense of Unity among team members, and consider cultural and socioeconomic aspects. We examine the study's limitations and potential areas for future investigation
Screening Of Traditionally Used Endemic Soqotraen Plants For Cytotoxic Activity
Thirty extracts obtained from 10 endemic plant species belonging to 8 plant families used in the traditional medicine in Socotra have been tested for cytotoxic activity against FL-cells. Extracts of Eureiandra balfourii and Commiphora ornifolia showed the strongest activity against FL-cells with IC50 < 10 μg/ml and 39.3 μg/ml respectively. Keywords: Cytotoxicity, Soqotra, Fl-cellsAfrican Journal of Traditional and Complementary Medicine Vol. 4 (4) 2007: pp. 529-53
PI control of air temperature and humidity with a chilled water system
Uses a chilled water system to control temperature and humidity with a variable speed fan motor and variable position valves
The causes of prescribing errors in English general practices: a qualitative study
Background: Few detailed studies exist of the underlying causes of prescribing errors in the UK. Aim: To examine the causes of prescribing and monitoring errors in general practice and provide recommendations for how they may be overcome. Design and setting: Qualitative interview and focus group study with purposive sampling of English general practices. Method: General practice staff from 15 general practices across three PCTs in England participated in a combination of semi-structured interviews (n = 34) and six focus groups (n = 46). Thematic analysis informed by Reason’s Accident Causation Model was used. Results: Seven categories of high-level error-producing conditions were identified: the prescriber, the patient, the team, the working environment, the task, the computer system, and the primary–secondary care interface. These were broken down to reveal various error-producing conditions: the prescriber’s therapeutic training, drug knowledge and experience, knowledge of the patient, perception of risk, and their physical and emotional health; the patient’s characteristics and the complexity of the individual clinical case; the importance of feeling comfortable within the practice team was highlighted, as well as the safety implications of GPs signing prescriptions generated by nurses when they had not seen the patient for themselves; the working environment with its extensive workload, time pressures, and interruptions; and computer-related issues associated with mis-selecting drugs from electronic pick-lists and overriding alerts were all highlighted as possible causes of prescribing errors and were often interconnected. Conclusion: Complex underlying causes of prescribing and monitoring errors in general practices were highlighted, several of which are amenable to intervention
Solving conformable Gegenbauer differential equation and exploring its generating function
In this manuscript, we address the resolution of conformable Gegenbauer
differential equations. We demonstrate that our solution aligns precisely with
the results obtained through the power series approach. Furthermore, we delve
into the investigation and validation of various properties and recursive
relationships associated with Gegenbauer functions. Additionally, we introduce
and substantiate the conformable Rodriguez's formula and generating functio
The effect of different bleaching protocols, used with and without sodium ascorbate, on bond strength between composite and enamel
This in vitro study aims to evaluate whether a solution of 10% sodium ascorbate (SA) may exert a beneficial effect on the bonding of composite to enamel after using different bleaching agents and protocols. Microtensile bond strength (μTBS) was evaluated on 72 freshly extracted human central incisors, divided into eight experimental groups and one control group (total n = 9): Group 1 serves as control (nonbleached). Group 2 was bleached with 5% carbamide peroxide. Group 3 was bleached with 5% carbamide peroxide and then treated with 10% SA. Group 4 was bleached with 10% carbamide peroxide. Group 5 was bleached with 10% carbamide peroxide, then treated with 10% SA. Group 6 was bleached with 16% carbamide peroxide. Group 7 was bleached with 16% carbamide peroxide, then treated with 10% SA. Group 8 was bleached with 6% hydrogen peroxide. Group 9 was bleached with 6% hydrogen peroxide, then treated with 10% SA. All groups were restored immediately after the different treatments using a resin composite. The μTBS values were measured using a universal testing machine and statistical analysis was performed by means of normality and variance analyses, SIDAK test for univariate test and multiple comparisons, and Student test to compare μTBS values of each group with the control. The mean μTBS values in groups 2, 4, 6, 8 were significantly lower than controls. For groups 3, 5, 7, 9, subjected to antioxidant (10% SA) application, all μTBS values increased significantly. However, only for Groups 3 and 5 there was no significant difference with the control. Applying 10% SA for 10 min may improve the bond strength composite/bleached enamel just when whitening is performed with 5% and 10% carbamide peroxide
Optical and Hybrid Imaging and Processing for Big Data Problems
(First paragraph) The scientific community has been dealing with big data for a long time. Due to advancement in sensing, networking, and storage technology, other domains such as business, health, and social media followed. Data are considered the gold of the 21st century and are being collected, stored, and analyzed at a rapid pace. The amount of data being collected creates a compelling case for investing in hardware and software research to support generating even more data from new sensors and with better quality. It also creates a compelling case for investing in research and development of new hardware and software for data analytics. This special section of Optical Engineering explores the optical and hybrid imaging and processing technology that will enable capturing and analyzing large amounts of data or help stream the data for further exploration and analysis
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