Design of Adiabatic MTJ-CMOS Hybrid Circuits

Low-power designs are a necessity with the increasing demand of portable devices which are battery operated. In many of such devices the operational speed is not as important as battery life. Logic-in-memory structures using nano-devices and adiabatic designs are two methods to reduce the static and dynamic power consumption respectively. Magnetic tunnel junction (MTJ) is an emerging technology which has many advantages when used in logic-in-memory structures in conjunction with CMOS. In this paper, we introduce a novel adiabatic hybrid MTJ/CMOS structure which is used to design AND/NAND, XOR/XNOR and 1-bit full adder circuits. We simulate the designs using HSPICE with 32nm CMOS technology and compared it with a non-adiabatic hybrid MTJ/CMOS circuits. The proposed adiabatic MTJ/CMOS full adder design has more than 7 times lower power consumtion compared to the previous MTJ/CMOS full adder

Stochastic method for in-situ damage analysis

Based on the physics of stochastic processes we present a new approach for structural health monitoring. We show that the new method allows for an in-situ analysis of the elastic features of a mechanical structure even for realistic excitations with correlated noise as it appears in real-world situations. In particular an experimental set-up of undamaged and damaged beam structures was exposed to a noisy excitation under turbulent wind conditions. The method of reconstructing stochastic equations from measured data has been extended to realistic noisy excitations like those given here. In our analysis the deterministic part is separated from the stochastic dynamics of the system and we show that the slope of the deterministic part, which is linked to mechanical features of the material, changes sensitively with increasing damage. The results are more significant than corresponding changes in eigenfrequencies, as commonly used for structural health monitoring.Comment: This paper is accepted by European Physical Journal B on November 2. 2012. 5 pages, 5 figures, 1 tabl

Employment of single-diode model to elucidate the variations in photovoltaic parameters under different electrical and thermal conditions

In this research work, numerical simulations are performed to correlate the photovoltaic parameters with various internal and external factors influencing the performance of solar cells. Single-diode modeling approach is utilized for this purpose and theoretical investigations are compared with the reported experimental evidences for organic and inorganic solar cells at various electrical and thermal conditions. Electrical parameters include parasitic resistances (Rs and Rp) and ideality factor (n), while thermal parameters can be defined by the cells temperature (T). A comprehensive analysis concerning broad spectral variations in the short circuit current (Isc), open circuit voltage (Voc), fill factor (FF) and efficiency (η) is presented and discussed. It was generally concluded that there exists a good agreement between the simulated results and experimental findings. Nevertheless, the controversial consequence of temperature impact on the performance of organic solar cells necessitates the development of a complementary model which is capable of well simulating the temperature impact on these devices performance

HRM formality differences in Pakistani SMEs: a three-sector comparative study

Purpose Guided by institutional theory, this empirical paper examines variations in the adoption of HRM practices among SMEs in three different business sectors (services, manufacturing and trade). Design/methodology/approach Data from 300 owners/managers representing three business sectors were collected through a survey method. Findings The results suggest that service SMEs use more formal HRM practices than manufacturing and trade SMEs. Manufacturing SMEs are more formal than trade firms. Results are not affected by firm age. Research limitations/implications Social desirability bias may have influenced respondents into portraying a positive image of the organization by inflating HRM sophistication. A further limitation is that the performance of the firms was not measured. As such, it is not possible to judge whether greater HRM formality correlated with improved organizational performance. Practical implications This study shows how the business sector shapes HRM practices in Pakistani SMEs. Findings help to inform Pakistan's Small and Medium Enterprise Development Authority (SMEDA) in dealings with manufacturing and trade firms in terms of improving HRM practices. Originality/value Given the important role of SMEs in economic development, comparative research on HRM in SME contexts is scarce. Since SMEs are vital for Pakistan's economy, an improved understanding of the sector's approach to human resource development is important. The findings extend the boundaries of prior comparative HRM literature in SMEs by addressing sector influences while controlling for contextual factors

Theory and applications of atomic and ionic polarizabilities

Atomic polarization phenomena impinge upon a number of areas and processes in physics. The dielectric constant and refractive index of any gas are examples of macroscopic properties that are largely determined by the dipole polarizability. When it comes to microscopic phenomena, the existence of alkaline-earth anions and the recently discovered ability of positrons to bind to many atoms are predominantly due to the polarization interaction. An imperfect knowledge of atomic polarizabilities is presently looming as the largest source of uncertainty in the new generation of optical frequency standards. Accurate polarizabilities for the group I and II atoms and ions of the periodic table have recently become available by a variety of techniques. These include refined many-body perturbation theory and coupled-cluster calculations sometimes combined with precise experimental data for selected transitions, microwave spectroscopy of Rydberg atoms and ions, refractive index measurements in microwave cavities, ab initio calculations of atomic structures using explicitly correlated wave functions, interferometry with atom beams, and velocity changes of laser cooled atoms induced by an electric field. This review examines existing theoretical methods of determining atomic and ionic polarizabilities, and discusses their relevance to various applications with particular emphasis on cold-atom physics and the metrology of atomic frequency standards.Comment: Review paper, 44 page

The Circumnuclear Star-forming Activities along the Hubble Sequence

In order to study the circumnuclear star-forming activity along the Hubble sequence, we cross-correlate the Sloan Digital Sky Survey Data Release 2 (SDSS DR2) with the Third Reference Catalog of Bright Galaxies (RC3) to derive a large sample of 1015 galaxies with both morphological and spectral information. Among these, 385 sources are classified as star-forming galaxies and the SDSS fibre covered the circumnuclear regions (0.2 $-$ 2.0 kpc). By using the spectral synthesis method to remove the contribution from the underlying old stellar population, we measure the emission lines fluxes accurately which are then used to estimate the star formation rates(SFRs). Our main findings are that: (1) Early-type spirals show much larger H$\alpha$ luminosities and hence higher SFRs, they also suffer more extinctions than late-type ones. The equivalent widths (EWs) of H$\alpha$ emission lines show the similar trend, however, the very late types (Sdm $\sim$ Irr) do have large fractions of high EWs. (2) We confirm that D$_n(4000)$ has strong correlation with the strengthes of metallic absorption lines (such as CN band, G band and Mg Ib). Both these lines and the Balmer absorption lines show interesting variations between Sbc to Sd type galaxies. (3) The bar structure tightly relates with the enhanced star forming activity, this effect is even more significant in the early-type spirals. But we should note that the bar structure is not a necessary or sufficient condition for galaxies to harbor circumnuclear star formations.Comment: 14 pages, 15 figures, accepted for publication in A&

Clinical and histopathological observations of autologous bone marrow stromal cells implantation on the regeneration of sciatic nerve neurotmesis in rabbit

The peripheral nerve injuries (PNI) is due to stretching and laceration. Therefore, the epineural repair technique is currently accepted as a standard method for peripheral nerve repair. Thirty-two (32) rabbits were divided equally into perineural nerve sutures as control group (CG) and bone marrow stromal cells (BMSCs) as the treatment group (TG). The aim of this study was to investigate the effect of the autologous BMSCs implantation on the regeneration of sciatic nerve neurotmesis in rabbits. There was significant improvement (p<0.05) of the motor and sensory functions in the TG animals as compared to the CG. Histopathological examinations of the proximal nerve stump in the CG showed mild adherence surrounding an anastomosed area, few vacuolation and plenty of collagen at the peri and epineurium. The anastomosed site showed the degeneration, disorientation and giant cell surrounding the stitches, while intraneurial scar tissues were seen in the distal segment at the 112th post operation day (POD). The histopathology of TG showed the activated Schwann cells, good myelination, minimum scar tissue, good orientation and remarkable angiogenesis at the 112th POD. BMSCs are capable of improving the motor and sensory functions and significantly promote the regeneration of sciatic nerve neurotmesis in rabbits.Key words: Clinical, histopathological, bone marrow stromal cells (BMSCs), neurotmesis, sciatic nerve, rabbit

A Novel Water Quality Index for Iraqi Surface Water

هدفت هذه الدراسة الى بناء موديل لنوعية المياه يكون مناسب للنظم المائية العراقي ويعكس الواقع البيئي للمياه العراقية. دليل نوعية المياه العراقية المطور يتضمن عوامل فيزيائية وكيميائية. من اجل بناء دليل نوعية المياه العراقي IQWQI  تم استخدام طريقة دلفي للتواصل مع الخبراء المحلين والعالميين المختصين بنوعية المياه لغرض الحصول على اراءهم بخصوص اهم العوامل المهمة التي يمكن استخدامها لبناء الدليل وحسب طبيعية النظام البيئي العراقي وتحديد وزن لكل عامل. 70% من البيانات التي تم الحصول عليها من هذه الدراسة قد استخدمت لبناء الدليل و 30% استخدمت لاختبار الدليل. تم تطبيق عدة سيناريوهات لمدخلات الموديل لغرض دراسة تأثير زيادة العوامل. تم بناء الموديل من 4 عوامل لأربع مرات جمع عينات حتى وصل الى 17 عامل لعشرة مرات جمع عينات. ومن الواضح انه عند زيادة عدد العوامل فان قيمة الدليل سوف تتغير. لغرض تقليل التأثير المخفي للعوامل التي تتجاوز المحددات المسموحة والذي يظهر عند استخدام WQI  ولحل هذا التداخل بين النوعية والتلوث فقد اوجدت هذه الدراسة دليل اخر يكون مرتبط بـ IQWQI والذي يضم كلا من درجة النوعية والتلوث. سمي الدليل الثاني دليل المخاطر البيئية ERI ويضم فقط العوامل التي تجاوزت الحدود البيئية المسموح بها. أجري تحليل الحساسية لغرض التنبؤ بقيم IQWQI وتحديد اهم العوامل المؤثرة في قيم IQWQI، تم اختيار موديلين  لأجراء تحليل الحساسية وهما انحدار الشبكة العصبية الاصطناعية والمعتمد على التعلم الالي ((ANNRThe study aims to build a water quality index that fits the Iraqi aquatic systems and reflects the environmental reality of Iraqi water. The developed Iraqi Water Quality Index (IQWQI) includes physical and chemical components. To build the IQWQI, Delphi method was used to communicate with local and global experts in water quality indices for their opinion regarding the best and most important parameter we can use in building the index and the established weight of each parameter. From the data obtained in this study, 70% were used for building the model and 30% for evaluating the model. Multiple scenarios were applied to the model inputs to study the effects of increasing parameters. The model was built 4 by 4 until it reached 17 parameters for 10 sampling times. Obviously, with the increasing number of parameters, the value of the index will change. To minimize the effect of eclipse that arises in WQI and to solve the problem of overlapping quality and pollution, this study has created another index linked with IQWQI, which included both the quality and the degree of pollution. The second index is called the Environmental Risk Index (ERI), where only the variables that exceed the permissible environmental limits were included. Sensitivity Analysis was done to predicate IQWQI and to determine the most influential parameters in the IQWQI score; two types of models were chosen for the run of the sensitivity test, which are the Artificial Neural Network Regression (ANNR) and Backward Linear Regression (BLR). The results of IWOI and ERI for freshwater use during the dry season were very poor water quality with a high degree of risk. While in the wet season, both indices' values ranged from poor water quality to very poor water quality with a high degree of risk

The Level of Ischemic Modified Albumin (IMA) as Risk Marker for Cardio Vascular D isease (CVD) among some diabetic patients (type II) in Khartoum state -Sudan

Background. Recent literature reports show large interest in ischemic modified albumin (IMA) biochemical marker for detection of myocardial injury. Special attention is focused in estimation of IMA test for the diagnosis and evaluation of myocardial ischemia as well as others acute coronary syndrome in emergency patients.Objective : evaluation of ischemia-modified albumin (IMA) in well controlled and uncontrolled patients with type 2 diabetes mellitus and estimation of its connection with cardiovascular disease.Measurement thelevelof IMA asrisk marker forcardio vascular disease (CVD) in diabetic patients that arrivedtoemergency department with signs and symptoms of CVD.Methodology. 140 subjects enrolled in thisstudy ,70 diabetes mellitus patients with signs and symptoms of CVD, and other 70 apparently non diabetic healthy subjects' as controls, , the levels of biomarker IMA was measured as the risk marker ofCVDin controlled and uncontrolleddiabeticpatients with type2,the Diagnostic potential was evaluated by receiver operating characteristic analysis and their relationships were analyzed. This study was donein Shab Hospital, Khartoum.Period from 1st of February 2015 to October 2015.Results: The results showed that CVD were predominant among diabetic female 57 % and peaked at age 75.5 years among 40-75 year old. The IMA was significantly increase in diabetic patients when compare with normal healthy group with cut off value ( 0.97 IU/L ), and there is also significantly increase in IMA level in uncontrolled diabetic patients (Mean ± SD; 14.70 + 10.66) that presented with acute chest pain and havea signs and symptoms of cardiac ischemia when compared with the well-controlled diabetic patients(Mean ± SD; 3.74 + 3.68). controlled and uncontrolled diabetic patients were determined by the level of their HBA1c and comparison with the means of IMA level in their serum.Conclusions: increase IMA level in poor control and long stand diabetic patients could help to identify the higher risk for develop to CVD, and The most common complication such as suffering from local or systemic hypoxic conditions, as acute ischemic stroke, peripheral vascular disease.Keywords: Ischemia, Type 2 diabetes mellitus, cardiovascular disease, Ischemic Modified Albumi

The level of Ischemic Modified Albumin (IMA) as risk marker for Cardio Vascular Disease (CVD) among some diabetic patients (type II) in Khartoum State-Sudan

Background: Recent literature reports show large interest in ischemic modified albumin (IMA) biochemical marker for detection of myocardial injury. Special attention is focused in estimation of IMA test for the diagnosis and evaluation of myocardial ischemia as well as others acute coronary syndrome in emergencypatients.Objective: evaluation of ischemia-modified albumin (IMA) in well controlled and uncontrolled patients with type 2 diabetes mellitus and estimation of its connection with cardiovascular disease.Measurement the levelof IMA as risk marker for cardio vascular disease (CVD) in diabetic patients that arrived to emergency department with signs and symptoms of CVD.Methodology: 140 subjects enrolled in this study ,70 diabetes mellitus patients with signs and symptoms of CVD, and other 70 apparently non diabetic healthy subjects’ as controls, , the levels of biomarker IMA was measured as the risk marker of CVDin controlled and uncontrolled diabeticpatients with type2,the Diagnostic potential was evaluated by receiver operating characteristic analysis and their relationships were analyzed. This study was done in Shab Hospital, Khartoum. Period from 1st of February 2015 to October 2015.Results: The results showed that CVD were predominant among diabetic female 57 % and peaked at age 75.5 years among 40-75 year old. The IMA was significantly increase in diabetic patients when compare with normal healthy group with cut off value ( 0.97 IU/L ), and there is also significantly increase in IMA level in uncontrolled diabetic patients (Mean ± SD; 14.70 + 10.66) that presented with acute chest pain and havea signs and symptoms of cardiac ischemia when compared with the wellcontrolled diabetic patients (Mean ± SD; 3.74 ± 3.68). controlled and uncontrolled diabetic patients were determined by the level of their HBA1c and comparison with the means of IMA level in their serum.Conclusions: increase IMA level in poor control and long stand diabetic patients could help to identify the higher risk for develop to CVD, and The most common complication such as suffering from local or systemic hypoxic conditions, as acute ischemic stroke, peripheral vascular disease.Keywords: Ischemia, Type 2 diabetes mellitus, cardiovascular disease, Ischemic Modified Albumi