5,183 research outputs found
Emotional Intelligence and Personal Development in Employees: a Case Study of Zigron Corporation, Pakistan
Article sought to explore the potential role of Emotional Intelligence (EI) in the personal development of organizational employees and to find out the scope of emotional intelligence for personal development of individuals. This study was qualitative in nature; however, to ensure the authenticity and generalizability of the results some quantitative analysis analyses were applied. Using case study method and taking interviews from 17 software house engineers of Zigron Corporation in Pakistan, this study suggests that emotional intelligence plays a crucial role in the personal development of individuals
Technical Analysis of Organic Rankine Cycle System Using Low-Temperature Source to Generate Electricity in Ship
Nowadays, the shipping sector has growth rapidly as followed by the increasing of world population and the demands for public transportation via sea. This issue entails the large attention on emission, energy efficiency and fuel consumption on the ship. Waste Heat Recovery (WHR) is one of the solution to overcome the mentioned issue and one of the WHR method is by installing Organic Rankine Cycle (ORC) system in ship. ORC demonstrate to recover and exploit the low temperature waste heat rejected by the ship power generation plant. The main source of heat to be utilized is obtained from container ship (7900 kW BHP, DWT 10969 mt) ship jacket water cooling system and use R-134a as a refrigerant. The main equipment consists of evaporator, condenser, pump and steam turbine to generate the electricity. The main objective is to quantifying the estimation of electrical power which can be generated at typical loads of the main engine. As the final result of analysis, the ORC system is able to generate the electricity power ranged from 77,5% - 100% of main engine load producing power averagely 57,69 kW
High sensitivity and multifunctional micro-Hall sensors fabricated using InAlSb/InAsSb/InAlSb heterostructures
Further diversification of Hall sensor technology requires development of materials with high electron mobility and an ultrathin conducting layer very close to the material's surface. Here, we describe the magnetoresistive properties of micro-Hall devices fabricated using InAlSb/InAsSb/InAlSb heterostructures where electrical conduction was confined to a 30 nm-InAsSb two-dimensional electron gas layer. The 300 K electron mobility and sheet carrier concentration were 36 500 cm(2) V-1 s(-1) and 2.5 x 10(11) cm(-2), respectively. The maximum current-related sensitivity was 2 750 V A(-1) T-1, which was about an order of magnitude greater than AlGaAs/InGaAs pseudomorphic heterostructures devices. Photolithography was used to fabricate 1 mu m x 1 mu m Hall probes, which were installed into a scanning Hall probe microscope and used to image the surface of a hard disk
Carotid plaque hemorrhage on magnetic resonance imaging strongly predicts recurrent ischemia and stroke
Objective
There is a recognized need to improve selection of patients with carotid artery stenosis for carotid endarterectomy (CEA). We assessed the value of magnetic resonance imaging (MRI)-defined carotid plaque hemorrhage (MRIPH) to predict recurrent ipsilateral cerebral ischemic events, and stroke in symptomatic carotid stenosis.
Methods
One hundred seventy-nine symptomatic patients with ≥50% stenosis were prospectively recruited, underwent carotid MRI, and were clinically followed up until CEA, death, or ischemic event. MRIPH was diagnosed if the plaque signal intensity was >150% that of the adjacent muscle. Event-free survival analysis was done using Kaplan–Meier plots and Cox regression models controlling for known vascular risk factors. We also undertook a meta-analysis of reported data on MRIPH and recurrent events.
Results
One hundred fourteen patients (63.7%) showed MRIPH, suffering 92% (57 of 62) of all recurrent ipsilateral events and all but 1 (25 of 26) future strokes. Patients without MRIPH had an estimated annual absolute stroke risk of only 0.6%. Cox multivariate regression analysis proved MRIPH as a strong predictor of recurrent ischemic events (hazard ratio [HR] = 12.0, 95% confidence interval [CI] = 4.8–30.1, p < 0.001) and stroke alone (HR = 35.0, 95% CI = 4.7–261.6, p = 0.001). Meta-analysis of published data confirmed this association between MRIPH and recurrent cerebral ischemic events in symptomatic carotid artery stenosis (odds ratio = 12.2, 95% CI = 5.5–27.1, p < 0.00001).
Interpretation
MRIPH independently and strongly predicts recurrent ipsilateral ischemic events, and stroke alone, in symptomatic ≥50% carotid artery stenosis. The very low stroke risk in patients without MRIPH puts into question current risk–benefit assessment for CEA in this subgroup
Optimal deep brain stimulation site and target connectivity for chronic cluster headache
OBJECTIVE: To investigate the mechanism of action of deep brain stimulation for refractory chronic cluster headache and the optimal target within the ventral tegmental area. METHODS: Seven patients with refractory chronic cluster headache underwent high spatial and angular resolution diffusion MRI preoperatively. MRI-guided and MRI-verified electrode implantation was performed unilaterally in 5 patients and bilaterally in 2. Volumes of tissue activation were generated around active lead contacts with a finite-element model. Twelve months after surgery, voxel-based morphometry was used to identify voxels associated with higher reduction in headache load. Probabilistic tractography was used to identify the brain connectivity of the activation volumes in responders, defined as patients with a reduction of ≥30% in headache load. RESULTS: There was no surgical morbidity. Average follow-up was 34 ± 14 months. Patients showed reductions of 76 ± 33% in headache load, 46 ± 41% in attack severity, 58 ± 41% in headache frequency, and 51 ± 46% in attack duration at the last follow-up. Six patients responded to treatment. Greatest reduction in headache load was associated with activation in an area cantered at 6 mm lateral, 2 mm posterior, and 1 mm inferior to the midcommissural point of the third ventricle. Average responders' activation volume lay on the trigeminohypothalamic tract, connecting the trigeminal system and other brainstem nuclei associated with nociception and pain modulation with the hypothalamus, and the prefrontal and mesial temporal areas. CONCLUSIONS: We identify the optimal stimulation site and structural connectivity of the deep brain stimulation target for cluster headache, explicating possible mechanisms of action and disease pathophysiology
Magnetic resonance imaging plaque hemorrhage for risk stratification in carotid artery disease with moderate risk under current medical therapy
Background and Purpose—Magnetic resonance imaging (MRI)–defined carotid plaque hemorrhage (MRIPH) can predict recurrent cerebrovascular ischemic events in severe symptomatic carotid stenosis. It is less clear whether MRIPH can improve risk stratification despite optimized medical secondary prevention in those with moderate risk.
Methods—One-hundred fifty-one symptomatic patients with 30% to 99% carotid artery stenosis (median age: 77, 60.5% men) clinically deemed to not benefit from endarterectomy were prospectively recruited to undergo MRI and clinical follow-up (mean, 22 months). The clinical carotid artery risk score could be evaluated in 88 patients. MRIPH+ve was defined as plaque intensity >150% that of adjacent muscle. Survival analyses were performed with recurrent infarction (stroke or diffusion-positive cerebral ischemia) as the main end point.
Results—Fifty-five participants showed MRIPH+ve; 47 had low, 36 intermediate, and 5 high carotid artery risk scores. Cox regression showed MRIPH as a strong predictor of future infarction (hazard ratio, 5.2; 95% confidence interval, 1.64–16.34; P=0.005, corrected for degree of stenosis), also in the subgroup with 50% to 69% stenosis (hazard ratio, 4.1; 95% confidence interval, 1–16.8; P=0.049). The absolute risk of future infarction was 31.7% at 3 years in MRIPH+ve versus 1.8% in patients without (P<0.002). MRIPH increased cumulative risk difference of future infarction by 47.1% at 3 years in those with intermediate carotid artery risk score (P=0.004).
Conclusions—The study confirms MRIPH to be a powerful risk marker in symptomatic carotid stenosis with added value over current risk scores. For patients undergoing current secondary prevention medication with clinically uncertain benefit from recanalization, that is, those with moderate degree stenosis and intermediate carotid artery risk scores, MRIPH offers additional risk stratification
Benchmarking of a micro gas turbine model integrated with post-combustion CO2 capture
The deployment of post-combustion CO2 capture on large-scale gas-fired power plants is
currently progressing, hence the integration of the power and capture plants requires a
good understanding of operational requirements and limitations to support this effort. This
article aims to assist research in this area, by studying a micro gas turbine (MGT) integrated
with an amine-based post-combustion CO2 capture unit. Both processes were simulated
using two different software tools – IPSEpro and Aspen Hysys, and validated against
experimental tests. The two MGT models were benchmarked at the nominal condition, and
then extended to part-loads (50 and 80 kWe), prior to their integration with the capture
plant at flue gas CO2 concentrations between 5 and 10 mol%. Further, the performance of
the MGT and capture plant when gas turbine exhaust gases were recirculated was assessed.
Exhaust gas recirculation increases the CO2 concentration, and reduces the exhaust gas
flowrate and specific reboiler duty. The benchmarking of the two models revealed that the
IPSEpro model can be easily adapted to new MGT cycle modifications since turbine
temperatures and rotational speeds respond to reaching temperature limits; whilst a
detailed rate-based approach for the capture plant in Hysys resulted in closely aligned
simulation results with experimental data
Learning Moore Machines from Input-Output Traces
The problem of learning automata from example traces (but no equivalence or
membership queries) is fundamental in automata learning theory and practice. In
this paper we study this problem for finite state machines with inputs and
outputs, and in particular for Moore machines. We develop three algorithms for
solving this problem: (1) the PTAP algorithm, which transforms a set of
input-output traces into an incomplete Moore machine and then completes the
machine with self-loops; (2) the PRPNI algorithm, which uses the well-known
RPNI algorithm for automata learning to learn a product of automata encoding a
Moore machine; and (3) the MooreMI algorithm, which directly learns a Moore
machine using PTAP extended with state merging. We prove that MooreMI has the
fundamental identification in the limit property. We also compare the
algorithms experimentally in terms of the size of the learned machine and
several notions of accuracy, introduced in this paper. Finally, we compare with
OSTIA, an algorithm that learns a more general class of transducers, and find
that OSTIA generally does not learn a Moore machine, even when fed with a
characteristic sample
Vacuum Induced Coherences in Radiatively Coupled Multilevel Systems
We show that radiative coupling between two multilevel atoms having
near-degenerate states can produce new interference effects in spontaneous
emission. We explicitly demonstrate this possibility by considering two
identical V systems each having a pair of transition dipole matrix elements
which are orthogonal to each other. We discuss in detail the origin of the new
interference terms and their consequences. Such terms lead to the evolution of
certain coherences and excitations which would not occur otherwise. The special
choice of the orientation of the transition dipole matrix elements enables us
to illustrate the significance of vacuum induced coherence in multi-atom
multilevel systems. These coherences can be significant in energy transfer
studies.Comment: 13 pages including 8 figures in Revtex; submitted to PR
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