957 research outputs found
Optimization of received power and SNR for an indoor attocells network in visible light communication
White LEDs Visible Light Communication (VLC) is applied in communication and illumination simultaneously. It provides unrestrained frequency spectrum and a large bandwidth that produces a higher transmission rate and speed in short-range communication. Also, VLC was considered as a promising alternative technology to the radio frequency in the next generation of communication systems. In this paper, the optical attocells configuration and LEDs distribution are proposed for optimizing the received power and Signal-to-Noise Ratio (SNR) in the Line of Sight (LOS) propagation link. Besides that, the trade-off between minimum SNR and received power are investigated. The simulation results showed that the proposed model can save 6.25% of the total transmitted power, and the optical received power versus semi-angle and field of view have with about increased 16.5% and 27.54% respectively. Moreover, the SNR also has 7.4% improvement. Hence, the proposed configuration model has improved the performance of VLC systems and has widen the window for future improvement
Real time model validation and control of DC motor using matlab and USB
Mechatronics system needs motion or action of some sort. It is created by a force or torque that results in acceleration and displacement. To produce this motion or action, actuators are the device being used. There are many types of actuators and one of the common types of electromechanical actuators is the direct current (DC) motor. The main goal of this project is to estimate the actual model of DC motor and control its speed using an embedded system interfaced to computer. The model identification is achieved using simple and low cost data acquisition system. An Arduino Uno embedded board system is used to collect the data from the sensors, send it to the computer, and control the model. The data processing is performed using MATLAB/SIMULINK. The validation for both the model and the controller are verified through simulations and experiments. The identification and the controllers results were coherent and successful
A new optimization uniformity for indoor visible light communication systems using optical attocells configuration
The demand for high data rate, capacity, increasing user mobility as well as low power consumption is increasing daily, where it is considered as main the challenges facing the radio frequency (RF) technology. Therefore, an alternative technology called visible light communications (VLC) was adopted to overcome these challenges. This technology is expected to support 5G and beyond due to its high and free frequency offered, as well as robust security. The main problem of this research is, the distribution of a few numbers of optical attocells on the ceiling have caused multiple blind areas in the room, and resulted in nonuniformity distribution. Besides that, employing large numbers of optical attocells has caused a severe ISI, which degrades the system performance, and produced large RMS delay. Therefore, to avoid this problem, a new arrangement of optical attocells, in addition to optimizing the VLC system parameters is proposed. In this research, the proposed arrangement of optical attocells configuration models will improve the uniformity in terms of received power and SNR. The SAAHP, FOV, and CV are used to study the behavior of the two proposed models. The average received power of 2.85 dBm is obtained for the proposed Model Basic 2 that consists of 13 optical attocells, which varies from -0.57 to 4.92 dBm. Moreover, the average SNR of 75.37 dB is obtained for the proposed Model Basic 2, which varies from 68.52 to 79.5 dB. The maximum of received power and SNR is obtained at the center of the room. The better uniformity (CV) of 0.374 and 0.0283 are obtained for the received power and SNR respectively. Additionally, six various modulation techniques are studied to evaluate the proposed models, all modulations produced better BER (â¤10â6) at data rate 30 Mbps, while the higher order modulations (L-PPM and M-PAM) produced higher data rate reaching up to 100 Gbps with a BER â¤10â6. This research also investigated an industrial warehouse model with different heights level, where a data rate of 30 Mbps is achieved with acceptable received power and SNR respectively. A BER â¤10â6 is obtained with L-PPM and M-PAM modulation techniques
Image compression based on 2D Discrete Fourier Transform and matrix minimization algorithm
In the present era of the internet and multimedia, image compression techniques are essential to improve image and video performance in terms of storage space, network bandwidth usage, and secure transmission. A number of image compression methods are available with largely differing compression ratios and coding complexity. In this paper we propose a new method for compressing high-resolution images based on the Discrete Fourier Transform (DFT) and Matrix Minimization (MM) algorithm. The method consists of transforming an image by DFT yielding the real and imaginary components. A quantization process is applied to both components independently aiming at increasing the number of high frequency coefficients. The real component matrix is separated into Low Frequency Coefficients (LFC) and High Frequency Coefficients (HFC). Finally, the MM algorithm followed by arithmetic coding is applied to the LFC and HFC matrices. The decompression algorithm decodes the data in reverse order. A sequential search algorithm is used to decode the data from the MM matrix. Thereafter, all decoded LFC and HFC values are combined into one matrix followed by the inverse DFT. Results demonstrate that the proposed method yields high compression ratios over 98% for structured light images with good image reconstruction. Moreover, it is shown that the proposed method compares favorably with the JPEG technique based on compression ratios and image quality
Practical Evaluation of Solar Irradiance Effect on PV Performance
The sun radiation has very important effect on the performance of photovoltaic (PV) solar modules due to its variation from time to time. In this paper, the performance of SolaraÂŽ-130 PV module will be evaluated practically by using the solar model tester (SMT). The existing SMT can generate variable solar irradiance from 100 w/m2 up to 1050w/m2. The I-V and P-V curves are plotted automatically via software controlling program on the SMT. Different parameters are obtained from the SMT like: VOC, ISC,Vpm, Ipm, Rs, Rsh and fill factor. The results can be used for plotting the relation between the solar irradiances (G) and the corresponding short circuit currents (ISC), then the relation between G-I can be used for measuring the solar irradiance based on the short circuit current in that curve, which means instead of using the PV module for generating electricity, it can be used for measuring the sun radiation instead of using the Pyranometer device
The Significance of Appendix Preposition (from) in Quoting in General and Refraining from Specifying (Ayah of Magic as a Model)
The research is summarized in the works of the rule ``textual indefinite in general and its appearance in it,'' which means if (from) is added before the negative indefinite, it transfers the general indication from appearance and presumption, to quotation and interruption. On this basis, it is possible to weigh the statements based on general texts, and this includes the ruling on learning and teaching magic. As a dispute occurred among the jurists of the nation regarding the permissibility of his learning and teaching. Every Ayah contained in its context (from the excess) should be examined, considered, and contemplated in light of its significance. _ Are the Ayah's in this unique formula specific? _ In which section of the Shari'a does it most frequently appear? _ What is its relationship to preponderance when there is a difference in rulings? After the research, it was found that one of its most important meanings, connotations, benefits, and purposes is the quotation in general, and the prevention of its specification. Therefore, it is one of the strongest arguments in the jurisprudential dispute, so it frequently comes in the verses of oneness, and the transcendence of God Almighty is the signifier. It is in the field of doctrinal scientific issues that are more famous, and all of this indicates the importance of the rule, and what comes out with this rule is the preponderance of the prohibition of magic in all its forms, in contrast to those who preferred to learn and teach it. In research, guidance is given to the rule ``There is no general but it has been specified'' and to combine the different sayings in a good manner
Seroprevalence and some demographic factors associated with Toxoplasma gondii infection among female population in Duhok province, Iraq
Background: The causative agent of toxoplasmosis is Toxoplasma gondii which is an intracellular protozoan. It has an important role in abortion and congenital diseases in pregnant women, which lead to infant's defectiveness birth when pregnant, are exposed during pregnancy. Toxoplasmosis is one of the most prevalent and most successful parasitic infectious disease worldwide, due to its efficient transmission through the ingestion of tissue cysts in undercooked and infected meat, or the ingestion of oocysts in contaminated vegetables and water. The present study aimed to investigate the seroprevalence rate of anti-Toxoplasma gondii Abs and their relation to some demographic factors among females, in Duhok province/ Kurdistan Region/ Iraq.Methods: During the period from October 2016 to November 2017, a total of 792 random blood samples were collected from the female population of different ages (16-55) years and various socioeconomic classes, who attended Obstetrics and Gynecology Hospital, Azadi teaching hospital and Central Public Health Laboratory/ Duhok.Results: Out of 792 samples examined, 288 (36.3%) were seropositive from which 282 (35.61%) were found seropositive for IgG, while only six samples (0.76%) were seropositive for IgM. Regarding to occupation, the highest rate for chronic toxoplasmosis was reported in housewives followed by employed and students at rates of 40.19%, 22.3%, and 14.0%, respectively. These outcomes were statistically significant (p0.05). Conclusions: This study showed the importance of demographic factors to the epidemiology of T. gondii in females, which support the role of public health in the control of infectious diseases
Effects of Supervised and Unsupervised Constraint induced Movement Therapy in the management of Motor Functions among Hemiparetic Stroke Patients
INTRODUCTION:
Stroke is a rapidly developing clinical signs of focal or global disturbance of cerebral functions with symptoms lasting for 24 hours or longer or lasting to death with no other apparent cause of vascular origin.It is a major health issue not only because it is the third major cause of death but also because it leaves patients with several residual disabilities like physical dependence, in-coordination, cognitive decline, dementia and depression
OBJECTIVES:
1. To evaluate the effectiveness of supervised constraint induced movement therapy on motor functions among hemiparetic stroke patients.
2. To evaluate the effectiveness of unsupervised constraint induced movement therapy on motor functions among hemiparetic stroke patients.
3. To compare the effectiveness of supervised constraint induced movement therapy and of unsupervised constraint induced movement therapy on motor functions among hemiparetic stroke patients.
METHODOLOGY:
Study setting:
The study was conducted in physiotherapy outpatient department, RVS College of Physiotherapy, Sulur, Coimbatore.
Selection of subjects:
20 subjects were randomly selected who fulfilled the inclusion and exclusion criteria and were divided into two groups. Group A-Supervised Constraint Induced Movement Therapy,
Group B-Unsupervised Constraint Induced Movement Therapy.
Inclusion criteria:
⢠Hemiparetic stroke patients.
⢠Age: 50-60 years.
⢠History of not more than one episode of stroke.
⢠Patients who can make a simple communication.
⢠Patients who can maintain a sitting position for more than 30 minutes.
⢠No severe cognitive disorders.
⢠Those who are co-operative.
Exclusion criteria:
⢠Associated psychological disorders.
⢠Perceptual deficit.
⢠Significant visual & auditory impairment.
⢠Cognitive and perceptual deficits.
CONCLUSION:
20 hemiparetic stroke patients were included in this study and randomly divided into two groups and each group consisted of 10 subjects. Group A was treated with supervised Constraint Induced Movement Therapy. Group B was treated with Unsupervised Constraint Induced Movement Therapy. After three weeks of intervention upper extremity skills improved significantly. The statistical result shows that there is improvement in both the groups. When
comparing both, supervised constraint induced movement therapy showed more significant improvement in motor functions than unsupervised constraint induced movement therapy among hemiparetic stroke patients
Synthesis and Spectral Identification of Various New Ligands and Complexes with (Pb2+)
This paper involved ,synthesis of new four ligands & their complexes with lead ion (Pb2+) have been synthesized via coupling reaction of azo compound & condensation reaction of imine compounds , the resulting compound containing azo group (ligand1) linked with imine compound will react with (maleic anhydride , sodium azide , chloro acetyl chloride) to give other three ligands containing azo âheterocycles from ( azoâoxazepine , azo âtetrazole , azo âazetidine), All four ligands & their complexes were confirmed by spectral studies such as{FT.IRâspectra , 1H.NMR-spectra , UV.Vis âspectra , Atomic Absorption } , and physical studies such as { molar conductance ., solubility in different solvents  ., measurement of melting point } , with analytical studies such as stoichiometric of complexes ., determination of optimal conditions of complexes . It has been found that the four ligands behave as tridentate donor ligands forming chelates with (1:2) (Pb: ligand) stoichiometry . Keywords : optimal , conductance , coordination , donor
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