Characterization of a short microchannel device for surface cooling

The development of microchannel devices is expanded widely due to the demand for small scale electronic devices. In order to increase the capability of the electronic devices, high heat transfer performance with low energy consumption cooler is required. This study is focusing on the characterization of new short microchannel for surface cooling purposes with the channel dimension of 800 μm wide, 200 μm length, 100 μm depth and total area of one cm2. Deionized water is used as the transport medium. A map of microchannel characteristics is plotted in term of average thermal resistance, pumping power, power supplied and mass flow rate of the fluid. From this mapping, it is shown that the thermal resistance decreased as the pumping power decreased. The results also show that the heat flux has not affected the value of pumping power. The different for each heat flux value is ranged between 3 to 4 %. The mapping presented in this study provides potential characteristics information and conditions to apply this particular microchannel for surface cooling

Manajemen Konflik Pada Organisasi Sekolah Dalam Meningkatka Kinerja Guru Min Bener Kelipah Kecamatan Bener Kelipah Kabupaten Bener Meriah

: Conflict is the portion that can not be separated from human life. Since humans recognize real life then the conflict has been with humans. School as a gathering place for humans can not be separated from the problems of conflict, so that the conflict there were feeling lucky and some are feeling dirugikan.Manajemen conflict of school personnel seek to direct the difference into sameness of thought, of be peace and the ultimate goal of this research is to understand how conflict management in organizations can improve the performance of school teachers Kelipah MIN Bener Bener Kelipah District of the central highlands. The method used is descriptive method with qualitative approach. Data collection techniques used in this study were interviews, observation, and study documentation. The data analysis techniques with data reduction, data display and making conclusions and verification. That is the subject of this research is the principal, deputy principal and teacher. results showed that: (1) The causes of conflict in the MIN Bener Kelipah is the understanding of teachers and principals about the concept of false conflicts, pressure, feeling aggrieved, oppressed, abused, role conflict and welfare of teachers. (2) The positive impact caused by conflict tehadap teacher performance: is the creation of discipline, increased teacher performance, increasing the quality of the formation of character education respect others. mature attitude and togetherness. While the negative impacts of conflict is the creation of groups within the school organization, the opposition, the decline in teacher performance, stress or crazy. (3) The strategy of conflict control done is: Understanding teachers\u27 economic, social, emotional, psychological, character and character approaches and sanctions (4) barriers to overcome conflicts also often perceived namely: doubt in conflict resolution, the more senior age familial nature , emotional, cultural and social status. Recommendations from this study, using constructive management style, encouraging equal participation and maintain a positive relationship for the duration of the conflict, which creates an atmosphere kondusip for school personnel

Aluminum toxicity in acid sulfate soil alleviated with biogenic liming composites of blood cockle shell and palm kernel shell

Low crop yield from acid sulfate soil was caused by high concentrations of aluminum and iron in soil. Aluminum ion which cause root injury at root region inhibits the uptake of the nutrients by the root and lead to nutrient deficiency. Ground magnesium limestones can beapplied to overcome this problem but incurred more production cost. Biogenic liming agent from blood cockle shell and/or palm kernel shell are more cost effective and provide the essential element i.e. calcium. This study evaluate phase-association of Al in acid sulfate soil remediated using biogenic composites liming material using selective sequential extraction analysis. Biogenic liming composites were characterized for pH, proximate analysis and elemental composition. High ratio of BCS in composite retained Al in the residual form about 91.33%. Amelioration of soil with 100% PKS did not give significant reduction of the exchangeable Al.Keywords: soil remediation; phytotoxicity; abiotic stress; calcination; alkalinity

The design of IPT system for multiple kitchen appliances using class E LCCL circuit

Since many years ago, kitchen appliances are powered up by cable connected. This create a troublesome case as wire might tangle together and cause kitchen table messy. Due to this, wireless power technology (WPT) is introduced as its ability is to transmit power to load without physical contact. This leads to cordless solution better in safety as the product can be completely seal, highly expandable power range. This work focuses on the design of WPT based on inductive approach to power up multiple kitchen appliances. The selection of inductive approach over its partners capacitive and acoustic is mainly due to high power efficiency. Class E inverter is proposed here to convert the DC to AC current to drive the inductive link. A 1 MHz operating frequency is used. To ensure the circuit is robust with load variations, an LCCL impedance matching is proposed. This solution is table to maintain the output power if there is a slight change in load impedance. Finally, the developed prototype is able to supply 50V utput which can achieve power transmission up to 81.76%

Carbonization cbn550 effect on tensile properties of composite for marine structure application

The composites have gained commercial success, where strength, stiffness, durability and light weight are required as well as retardant capacity. Improvement has been made such new series of resin such as vinyl ester and epoxy type[1, 2]. However 95% of pleasure vessels and boats under 60 feet today are still made with polyester resin. The main consideration for most composite builders is cost, with performance and more importantly value for money often being a secondary consideration. Therefore, this study investigate the tensile - mechanical effects of mixing carbon black CBN550 with wax and non-wax type resin and manufactured according to fiber orientation of [0°] and [90°]. The 10% CBN550 exhibit highest reading for stress under [90°] fiber orientation and the lowest reading when arranged at [0°] fiber orientation. The preliminary study on CBN550 flammability has indicated the suitability for this study to pursue in. The structural composites samples of 1000 mm by 1000 mm prepared which consist of 10 of composite mats layer in combination of CSM 450 g/m2 and Woven Roving 600 g/m2. The carbon black (CB) volume fraction range from/with 0% to 20% volume fractions. Optical observation revealed the most suitable fraction of CBN550 in wax polyester resin is at 10% and non-wax polyester resin is also at 10%. The fire resistance behaviour of this CBN550 - CSM 450 g/m2 - Woven Roving 600 g/m2 composite (polyester wax) and polyester non wax was investigated previously as per[3]. This results are in line with the finding of the maximum load where the highest reading was recorded by the 10%CBN550 specimen. This study showed that the introduction of carbon black into the resin mixture helps reinforce the matrix materials. The results suggested that CBN550 mixture should attend to next level of experiment investigation such as oxygen content, TG value, microstructure and other mechanical destructive test. The CBN550 could be a suitable candidate for fire retardance application in marine composite structure

Sliding Mode Observer Based Controller for Active Steering Control

The purpose of this paper is to enhance the performance of steering control of a vehicle. A nonlinear sliding mode observer based active steering controller that will overcome the disturbances such as road condition and crosswind is proposed. Condition of stability is given by using Lyapunov stability theory that relates to sliding mode characteristics. The controller proves that it is able to stabilize the steering wheel better when disturbances such as braking action and crosswind are included in the system. Lastly, simulations are given to prove the validity of the controller stability. In the simulations, comparisons are made between the outcome of the uncontrolled, Linear Quadratic Regulator (LQR), Sliding Mode Controller (SMC) and Sliding Mode Observer Based Controller (SMOC)

The effect of N550 carbon black in polyester resin for fire-retardant application in marine composite

This paper presents the experimental investigation on the influence of N550 carbon black (CBN550) series in polyester resin (wax and non -wax type). The CBN550 was added into polyester resin at different weight percentages with a curing agent. The investigation is mainlyto study the effect on fire retardance application in marine composite structure. The fire-resistant structural composites samples of 1000 mm by 1000 mm prepared which consist of 10 of composite mats layer in combination of CSM 450 g/m2 and Woven Roving 600 g/m2. The carbon black (CB) volume fraction range from/with 0% to 20% volume fractions. Optical observation revealed the most suitable fraction of CBN550 in wax polyester resin is at 10% and non-wax polyester resin is also at 10%. The fire resistance behavior of this CBN550 - CSM 450 g/m2 - Woven Roving 600 g/m2 composite (polyester wax) and polyester non wax was investigated by Fire Test Procedure Code-Resolution A.653 [1]. Though smaller filler size escalates the rheological behavior and values outstandingly at initial reading compare to large particles but it slow down the curing processdue to its small particle size, large surface area and high dispersion rate. Experimental data showed the retardance level has been increased up to 56.66% in non-wax type polyester resin (10%/CBN550) and 30.14% in wax polyester resin (10%/CBN550). The improvement in fire resistance points are due to the presence of CBN550 which acts as a positive additive in both polyester resin wax and non-wax. Filling CBN550 in polyester resin also reduces the cost of theend products.The preliminary results suggested that CBN550should attend to next level of experiment investigation such as oxygen content, TG value, microstructure as well as mechanical destructive test. The CBN550 could be a suitable candidate for fire retardance application in marine composite structure.In conclusion, crystallinity of polyester resin increases with additional of CB particles

β-Divergence Nonnegative Matrix Factorization on Biomedical Blind Source Separation

β-divergence has been studied for years, but it is yet to be discovered thoroughly. In this paper, we proposed the nonnegative matrix factorization (NMF) by using β-divergence in blind source separation (BSS) on biomedical field. The proposed idea is basically aimed at the separation of normal heart sound with normal lung sound. Temporal codes and spectral basis were modelled into a separated source, which is applied to the synthesis and real life data using multiplicative update rules. In the experiment, estimated and original source were compared to evaluate the performance of various source separation algorithms within a general framework, where the original sources and the noise that perturbed the mixture were included

Numerical evaluation of thermo-hydraulic performance in fin-and-tube compact heat exchangers with different tube cross-sections

This study examined numericallythe Thermal-hydrodynamic properties of airflow in the fin-and-tube compact heat exchangers (FTCHEs) with considering different shapes of tubes in lowReynoldsnumbers. The influence of applying flat, oval and circular tube adjustments on the thermal and hydraulic characteristics of air flow were analyzed on the in-line tube arrangements. Establishing standard conditions, the study compared different geometries based on circular tubes of 10.459 mm diameter tubes with 25.4 mm longitudinal pitches and 25.4 mm transverse pitches. The other geometries of tubes were assumed in a stable and constant state preparing the same heat transfer surface area per unit volume as that of the nominal case. The results showed that the FTCHE with flat tubes gives the best area goodness factor (j/f) with in a certainrange of Reynoldsnumbers. In addition, FTCHE with flat tubes shown the best thermo-hydraulic performance and a significant augmentation of up to 10.83% and 35.63% in the average area goodness factor achieved accompanied by a decrease in the average friction factor of 17.02% and 43.41% in the flat tube case compared to the oval and circle tube shapes, respectively. It is concluded that the average area goodness factorfor the oval tube is about 25.04% higher than that of the circular tube, while the average friction factor for the oval tube is about 26.9% lower than that of the circular tube. This means that the flat tube has a better-combined thermal-hydraulic performance than the oval and circle tube