Adaptive Traffic Prioritization Algorithm Over Ad Hoc Network Using IEEE 802.11e

This thesis proposes an adaptive traffic prioritization algorithm over ad hoc network using IEEE 802.11e standard that defines a set of Quality of Service enhancements for wireless LAN applications through modifications to the Media Access Control (MAC) layer. The IEEE 802.11e standard aims to provide enhancements that allow traffic with specific requirements to be treated differently from normal traffic. Enhanced Distributed Channel Access (EDCA) is a fundamental and mandatory contention-based channel access method of IEEE 802.11e which delivers traffic based on differentiated Access Category (ACs). Each AC has its own queue and set of EDCA parameter values. Although IEEE 802.11e has been widely implemented in commercial hardware, the EDCA parameters are normally preset with some default values recommended by the standard. By default, the values of EDCA parameters are not open for changes. This has limited the performance as from literature review, a proper EDCA parameter manipulation will improve the network throughput performance. However, most existing research works on IEEE 802.11e EDCA parameter optimization are done either analytically or in simulated environments and hence are unable to provide its effectiveness in realistic scenarios. This is largely due to the several hurdles associated with real-life implementations which prohibit them to do so, such as hardware limitations, software restrictions, coding bugs in the wireless cards driver and so on.These challengess form part of the motivations behind this work. This thesis first investigates the impacts of EDCA parameters on the network performance and link conditions using open source software and commercially available hardware in ad hoc mode. An adaptive prioritization scheme (APS) is then proposed. The results obtained show that the proposed APS algorithm can improve the single-AC throughput performance up to 10.82% when compared to static EDCA. In dual-AC scenario, APS can improve the throughput performance up to 9.93% as compared to static EDCA, while another scheme in existing literature, R-AIFSN shows inconsistency in throughput performance. It is also found that the improvement is more significant in terms of the queue occupancy

Preparation and characterization of deer velvet antler/polyvinyl alcohol (DVA/PVA) scaffold for bone tissue engineering

Combining synthetic polymer with inorganic bioactive elements has been an exciting route for developing tissue engineering scaffolds, in particular for bone tissue regeneration. In this study we report the fabrication of novel porous scaffold composed of polyvinyl alcohol/ deer velvet antler (DVA/PVA) via freeze-drying technique. The, mineral content of deer velvet antler analyzed by ICPMS showed high content of calcium and phosphorus. Morphological observation revealed that the incorporation of DVA in the polymer matrix with the porous structures ranging from 35 to 100 mm. The FTIR demonstrated chemical interaction between DVA and PVA due to the reaction between calcium ions with hydroxyl. Thermal analysis showed significant temperature increase from 146.34°C to 384.48°C due to the degradation of the side chain of PVA and decomposition of the carbonate ions. The swelling behavior, the porosity, and the degradation rate of the DVA/PVA scaffold were meet the physiological demands of bone regeneration. After 7 days, DVA/PVA scaffold showed the increasing of water absorption and low degradation rate. Thus, the developed scaffold is believed to have a potential to be effectively used in bone tissue engineering applications

DeerA-OS Bone Void Filler

Deer antler containstrace elements such as calcium and phosphorus, promising material for bone substitution. Combination of bioactive elements (deer antler) with synthetic polymers (PVA). Standardized pores are within the range of ideal bone growth and comparable compressive strength with trabecular bone ~0.1-16 MPa. Addition of the bioactive elements improves the crystallization properties and thermal stability

Analysis of shared heritability in common disorders of the brain

ience, this issue p. eaap8757 Structured Abstract INTRODUCTION Brain disorders may exhibit shared symptoms and substantial epidemiological comorbidity, inciting debate about their etiologic overlap. However, detailed study of phenotypes with different ages of onset, severity, and presentation poses a considerable challenge. Recently developed heritability methods allow us to accurately measure correlation of genome-wide common variant risk between two phenotypes from pools of different individuals and assess how connected they, or at least their genetic risks, are on the genomic level. We used genome-wide association data for 265,218 patients and 784,643 control participants, as well as 17 phenotypes from a total of 1,191,588 individuals, to quantify the degree of overlap for genetic risk factors of 25 common brain disorders. RATIONALE Over the past century, the classification of brain disorders has evolved to reflect the medical and scientific communities' assessments of the presumed root causes of clinical phenomena such as behavioral change, loss of motor function, or alterations of consciousness. Directly observable phenomena (such as the presence of emboli, protein tangles, or unusual electrical activity patterns) generally define and separate neurological disorders from psychiatric disorders. Understanding the genetic underpinnings and categorical distinctions for brain disorders and related phenotypes may inform the search for their biological mechanisms. RESULTS Common variant risk for psychiatric disorders was shown to correlate significantly, especially among attention deficit hyperactivity disorder (ADHD), bipolar disorder, major depressive disorder (MDD), and schizophrenia. By contrast, neurological disorders appear more distinct from one another and from the psychiatric disorders, except for migraine, which was significantly correlated to ADHD, MDD, and Tourette syndrome. We demonstrate that, in the general population, the personality trait neuroticism is significantly correlated with almost every psychiatric disorder and migraine. We also identify significant genetic sharing between disorders and early life cognitive measures (e.g., years of education and college attainment) in the general population, demonstrating positive correlation with several psychiatric disorders (e.g., anorexia nervosa and bipolar disorder) and negative correlation with several neurological phenotypes (e.g., Alzheimer's disease and ischemic stroke), even though the latter are considered to result from specific processes that occur later in life. Extensive simulations were also performed to inform how statistical power, diagnostic misclassification, and phenotypic heterogeneity influence genetic correlations. CONCLUSION The high degree of genetic correlation among many of the psychiatric disorders adds further evidence that their current clinical boundaries do not reflect distinct underlying pathogenic processes, at least on the genetic level. This suggests a deeply interconnected nature for psychiatric disorders, in contrast to neurological disorders, and underscores the need to refine psychiatric diagnostics. Genetically informed analyses may provide important "scaffolding" to support such restructuring of psychiatric nosology, which likely requires incorporating many levels of information. By contrast, we find limited evidence for widespread common genetic risk sharing among neurological disorders or across neurological and psychiatric disorders. We show that both psychiatric and neurological disorders have robust correlations with cognitive and personality measures. Further study is needed to evaluate whether overlapping genetic contributions to psychiatric pathology may influence treatment choices. Ultimately, such developments may pave the way toward reduced heterogeneity and improved diagnosis and treatment of psychiatric disorders

Amnesia and its relation with concession (Rukhsah) on performing prayer (Solah)

The low percentage of in-ward patients that performing solah during their stay in hospital indicatess a worrying trend attributed to the minimal knowledge of rukhsah for solah during certain illness. Among the illness which could affect the ability of a Muslim to perform their act of worship is a memory disorder known as amnesia. There are several types of amnesia and classification where each of them manifest different level of severity. The different level of severity requires level of of rukhsah in solah. This review was conducted based on narrative review framework and integrated with Islamic Perspective by framework analysis. In relation to that, the distinction between ‘aqil and ghairu ‘aqil person is identified where transient global amnesia is suggested as ‘aqil person meanwhile the Korsakoff’s syndrome and global psychogenic amnesia is suggested as the ghairu ‘aqil person. For a person who is regarded as ghairu ‘aqil, the obligation of solah is accrued and they are not required to qada’ the solah after memory disorder is preserved. As part of the concession to the Muslim amnesic patient, they are permitted to perform the solah in jama’. In conclusion, the severity of the amnesic syndrome varies based on their classifications and the practice of rukhsah on solah should be in accordance to the principles of rukhsoh

A narrative review on pathology of amnesia and its relation with cessation (Rukhsah) of performing prayer (Solah)

Background: The low percentage of in-ward patients that performing solah (prayer) during their stay in hospital shows the worrying trend because of the minimal knowledge of rukhsah (concession) in solah during certain illness. One of the illness that is difficult to determine the rukhsah is memory disturbance such as amnesia. Amnesia is the memory impairment whether the inability to retrieve the past memory (retrograde amnesia) or the inability to learn new information (anterograde amnesia). Thus, the aim of this study is to review the pathology of amnesia based on current literature review and to relate with the rukhsah in solah among amnesia patients. In Islam, the principle of applying the rukhsah kept an open concept for the application in most disabilities and handicaps. Therefore, with the general guidelines of rukhsah on solah for ghairu ‘aqil (insane) patients by JAKIM, so, this study can be complement to that guideline in term to propose some guidelines of rukhsah on solah among the muslim amnesia patients. Methods: The review will be conducted based on narrative review framework that consist of several steps which are identification of the study; search of relevant work or publication; collection, extraction and synthesis of data; and writing the report. The framework analysis will be discussed from various aspects such as the Islamic worldview, Islamic Jurisprudence (fiqh), consensus by Islamic Scholars (ijma’), contribution of Islamic Scholars, principles (qawaid) and objective (maqasid) of the syariah, and Islamic civilization and history. These analyses are based on the Holy Quran and Hadith. Results: This study is attempt to provide the preliminary suggestion of the rukhsah of solah among the muslim amnesia patient based on the pathological condition of amnesia. in relation with that, the severity of amnesia can be extent until the patient become unconscious about him/herself. This patient is not obligate to perform the solah because they are considered ghairu ‘aqil (insane). While for certain type of amnesia, the patient identity is still intact and remain conscious about him/herself. As for this condition, the patient is obligate to perform the solah because they are considered ‘aqil (sane). Conclusion: In conclusion, the severity of amnesic syndrome is varies based on their classification and must be reviewed comprehensively. Therefore, the rukhsah of solah among the muslim amnesia patients based on the severity of the amnesia can be decided

Amnesia and its relation with concession (Rukhsah) on performing prayer (Solah)

The low percentage of in-ward patients that performing solah during their stay in hospital indicatess a worrying trend attributed to the minimal knowledge of rukhsah for solah during certain illness. Among the illness which could affect the ability of a Muslim to perform their act of worship is a memory disorder known as amnesia. There are several types of amnesia and classification where each of them manifest different level of severity. The different level of severity requires level of of rukhsah in solah. This review was conducted based on narrative review framework and integrated with Islamic Perspective by framework analysis. In relation to that, the distinction between ‘aqil and ghairu ‘aqil person is identified where transient global amnesia is suggested as ‘aqil person meanwhile the Korsakoff’s syndrome and global psychogenic amnesia is suggested as the ghairu ‘aqil person. For a person who is regarded as ghairu ‘aqil, the obligation of solah is accrued and they are not required to qada’ the solah after memory disorder is preserved. As part of the concession to the Muslim amnesic patient, they are permitted to perform the solah in jama’. In conclusion, the severity of the amnesic syndrome varies based on their classifications and the practice of rukhsah on solah should be in accordance to the principles of rukhsoh

Optimization of the flow characteristic in various array arrangements of multiple picohydro power turbines

Renewable energy is an energy which is generated from the natural resources such as wind, water, sunlight, rain and geothermal. Naturally, it can be replenished. This energy can reduce the pollutions that occur all around the world. It is also can be the best solution for the global issue such as climate changes that is happened rapidly nowadays. Likewise, it is practically suitable in the rural areas or the remote areas because of the difficulty in getting fuel which is also expensive. Micro hydropower (MHP) is one of renewable energy resources in the world. Hydro turbines are used to change water pressure from river flow into mechanical or kinetic energy, which can generate electricity. It can be classified by its capacity such as pico, mini, and small which the power are up to 100KW, 1MW and 25MW respectively. Accordingly, MHP is the most economical technology to generate power. This is because MHP use the water flow in a river to generate power, where it is a continuous process. Besides, the costs for manufacture and install MHP turbines are cheaper compared to the tidal and wind turbines. Most of the computational researches on arrays arrangement are done for tidal turbines, which is almost similar to MHP turbines. Computational Fluid Dynamics (CFD) models are used to analyze the wake effects in arrays of tidal turbines. The simulations of the turbines are done to obtain the wake characteristics of actuator disc and compare with experimental data. According to, Fluent software is used to simulate 3-D models of Tidal Energy Converter (TEC) turbines with three-row array. In this research, the TEC array arrangement and spacing simulated to identify the performance variation of electrical power output. Besides that, adaptive mesh method with Gerris solver is used to optimize multiple arrays of picohydro turbines in a channel. Reynolds-averaged Navier Stokes (RANS) equations are used with the turbines to stand for frozen rotor. Static blade method is similar with the frozen rotor method. The frozen rotor method is used in the computational domain to consider effect of velocity on it. The CFD software is used here to analyse the best 3D array arrangement of river picohydro turbines, which generate maximum power output. Meanwhile, the MATLAB and DasyLab simulations will validate the CFD results obtained from a single picohydro turbine at three different locations

Synthesis of I@MPA-Mn:ZnSe as an efficient contrast agent for CT/ fluorescence bi-modal imaging application

Bi-modal imaging contrast agent has attracted considerable attention in medical physics research field via quantum dots (QDs) fabrications. Doped quantum dots are playing an important role in seeking alternatives to conventional heavy metal-containing particles for medical applications. In order to improve imaging diagnosis, herein we report the design and synthesis of I@MPA-Mn:ZnSe as an efficient contrast agent. The medium, mercaptopropionic acid (MPA) capped Mn:ZnSe QDs surface-conjugated with a commercial contrast agent (Iohexol), was synthesized in seeking to overcome the limitations of Iohexol, also towards advancing bi-modal imaging approaches. In this study, morphology, elemental, absorption and fluorescence analysis were investigated, followed by a preliminary study of CT contrast enhancement and cell viability. In comparison to Iohexol, the fluorescence of I@MPA-Mn:ZnSe is observed at 585 nm. The CT Hounsfield unit (HU) increases linearly with mass concentration, with a four-fold increment in HU over that of Iohexol, producing greater than 328 ΔHU at similar concentrations, confirming the CT contrast efficiency of I@MPA-Mn:ZnSe. Cytotoxicity studies have confirmed that the medium possesses good biocompatibility and low toxicity to cells (HepG2 and MDA-MB-321). Present results for CT enhancement and brightness of fluorescence of I@MPA-Mn:ZnSe point to its great potential as a bi-modal contrast medium for further diagnosis applications