202 research outputs found
Heat transfer study in corrugated wall bubbling fluidized bed reactor: Experiments and CFD simulations
Gasification technology must ideally be bestowed with the following traits: auto/allothermal process, non-diluted biosyngas abolishing downstream N2 separation or upstream O2 enrichment, thermal coupling via micro-segmentation between endothermic and exothermic steps to improve heat exchanges and enhance thermal efficiency, and high yield and heating value of biosyngas. These attributes represent the foremost challenges next-generation biomass steam gasifiers must cope with. With the endeavor of approaching such ideal configuration, Iliuta et al. proposed a reactor concept of allothermal cyclic multicompartment bubbling fluidized beds. Gas solid fluidized bed reactors would be used to obtain the enhanced heat and mass transport and conversion performances as compared to packed beds. Corrugated walls were installed in narrow gas-solid bubbling fluidized bed (CWBFB) enclosures to decrease minimum bubbling velocity, reduce bubble sizes, improve gas distribution, offer stable operation and minimize the particles carryover or loss. Thorough analyses of wall-to-bed heat transfer coefficient in flat- (FWBFB) and corrugated- (CWBFB) wall bubbling fluidized beds were performed for a variety of wall declinations and operating conditions covering a range of corrugation angles, inter-wall clearances (C), initial rest bed heights (Hi) and ratios of gas superficial velocity to minimum bubbling velocity, Ug/Umb (1-1.55). Fast response self-adhesive heat flux probes and thermocouples were employed to simultaneously measure the wall-to-bed heat flux, surface temperature and bed temperature. These instruments were used to measure the heat transfer coefficient (HTC) at different (18) axial and lateral locations. For a given set of parameters, significant increase in HTC was observed at lower gas flow rate in CWBFB as compared to FWBFB. It showed that CWBFB inventory required lesser Umb (gas flow rate) and offered more economical gas solid fluidization phenomena as compared to FWBFB. Full 3-D transient Euler-Euler CFD simulations employing kinetic theory of granular flow were also carried out which corroborated with experimental findings
An Efficient Approach for Generalized Load Balancing in Multipath Packet Switched Networks
This paper is a quantitative analysis on packet switched network with a view
to generalize load balancing and determination of appropriate routing algorithm
in multipath environment. Several routing algorithms have been introduced for
routing of packets from source to destination. Some of them route packets
accurately with increased workload and some of them drastically cut down the
workload. A few of them can find out a minimum workload deviation for both UDP
and TCP packets. We simulated these approaches in a well defined simulator,
analyzed and evaluated their performance. After expanding our analysis with
varying weights and number of paths we found that the recently proposed routing
algorithm Mixed Weighted Fair Routing (MWFR) outperforms the existing routing
algorithms by reducing the routing and network overhead and saving the scarce
bandwidth as well as CPU consumption for packet switching networks.Comment: 12 Pages, IJCNC Journal 201
Surgical Outcome of Endoscopic Third Ventriculostomy in Patients Having High ETV Success Score: One-Year Experience at a Tertiary Care Hospital
Background & Objective: Endoscopic third Ventriculostomy (ETV) is an accepted alternative to VP shunt in patients with obstructive hydrocephalus. We will share our experience and outcome.
Materials & Methods: Thirty consecutive ETV cases performed by a single surgeon during 1 year in patients with an ETV success score of 60 or higher were included in this study. Patients’ demographics, outcomes, and complications are reported.
Results: (60%) were male and 12 (40%) were female. The mean age in our study was 6.1 years ± 9 (mean ± SD). Posterior fossa tumor was the most common etiology in our series (46.6%) followed by aqueductal stenosis (23.3%). Eighty percent of our patients did not experience an ETV failure. The complication rate was 20%. Inadequate ventriculostomy in 6.6% of the patients was the commonest complication.
Conclusion: ETV is safe and effective in patients with high ETV success scores
Sedentary behaviour and physical activity levels in employees of Khyber Medical University Peshawar
Introduction: The increase in sedentary behaviour and decrease in physical activity levels are some of the contributing factors to many of the non-communicable diseases. These non-communicable diseases included obesity, type-II diabetes and cardiovascular problems. Apart from causing financial burden on health care system, these diseases have been reported to cause nearly 1.9 million premature deaths per year. The aim of the study was to measure sedentary behaviour and physical activity levels among employees of Khyber Medical University, Peshawar.
Material & Methods: A cross-sectional survey was conducted on employees of Khyber Medical University, Peshawar. The total sample size was 172 and the data was collected through convenience sampling by using International Physical Activity Questionnaire (IPAQ) long form. This questionnaire measures physical activity levels and sedentary behaviour at work.
Results: Out of 172 participants, 154 (89.5%) were male and 18 (10.4%) were female with a mean age of 34.4 ± 2 years. According to the levels of physical activity, 49 (28.5%) were less active, 63 (36.6%) were moderately active and 60 (34.9%) were highly active. The average time spent by the participants for sitting was (8.93 ± 2.35) hours per day. A total of 73.8%, 23.3 % and 2.9% participants could be categorised as having high, moderate and low sedentary behaviour, respectively.
Conclusion: Majority of the participants (two-thirds of the participants) demonstrated a high sedentary behaviour and therefore, needed modification in their daily routine
An analysis of the impact of soft skills on Malaysian technical institutions
Many people recognize the importance of technical skills as knowledge and proficiencies required in the accomplishment of professional jobs. However, the importance and applicability of soft skills are mostly ignored despite the fact that, it is a process how individual carry himself in an organization or professional environment for the progress of that individual and the organization he found himself. The paper explored into some journals from the previous the literatures, some soft skills were identified such as communication, lifelong learning, entrepreneurship, leadership, and teamwork, problem solving and critical among TVET institutions in Malaysia. Document analysis was conducted as a methodology for this study. The impacts of these soft skills on TVET related institutions like polytechnics, training centers and universities in Malaysia. It was indicated that, the result of the impact of soft skills on these institutions was generally moderate. The paper concluded that, technical skills alone could not bring about the organizational development there must be a compliment of soft skills for any organizational sustainability. Supplementary of soft and technical skills conceptual model was formulated. The paper was concluded by saying that, the competitive nature of the present situation, soft skills are essential because they have affected all aspect of human development. Some recommendations were suggested, teachers, lecturers and instructor must teach students soft skills for complete individual proficiencies and organizational sustainability
Financial development and environmental quality: The way forward
The present paper re-examines the asymmetric impact of financial development on environmental quality in Pakistan for the period 1985Q1 to 2014Q4. A comprehensive index of financial development is generated using Bank- and Stock market-based financial development indicators. The results show that inefficient use of energy adversely affects the environmental quality. This suggests adoption of energy efficient technology at both production and consumption levels. These technologies would be helpful to improve environmental quality, enhance the productivity in long-run and save energy. Bank-based financial development also impedes the environment. The government should encourage lenders to ease the funding for energy sector and allocate financial resources for environment friendly businesses rather than wasting them in consumer financing
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