Performance Analysis of Self-Consumed Solar PV System for A Fully DC Residential House

Malaysia is moving forward by promoting used of renewable energy such as solar PV to the public where it is generated at the distribution voltage level. The fluctuation of fuel prices becomes main concern to the consumers since it affecting the electricity tariff. The objective of this project is to design a self-consumed DC power system for a residential house from renewable energy resource which is solar PV that it will independent from the utility grid. The methodology proposed are configuring daily load demand, sizing PV array and battery bank and simulation of the design system by using PVsyst. Based on solar energy resource, the optimum PV array size is 2.0 kWp while the battery bank size is 700 Ah at 48 V which is designated for 4 days of autonomy. The system could meet 100% of load demand throughout the year with 67.9% of performance ratio. The loss to the system is contributed by the temperature effect to the PV module, unused energy because of battery full capacity, converter and battery efficiencies. Using this concept, the proposed design set-up is expected to benefit the residential consumers in reducing utility electricity consumption up to 2,434 kWh per year and avoiding 1.7 tons of carbon emissions into the environment annually

Learning style tendencies based on fleming’s VARK learning style among TVET students

This study aims to identify learning style tendencies based on the Fleming’s VARK learning style of TVET students. This study uses a questionnaire approach to assess TVET students' learning styles based on Fleming’s visual, auditory, writing or reading and kinesthetic learning styles. The study population is technical students of FPTV, UTHM and the selected sample consists of 53 students from various fields namely General Machining (BBA), Welding and Metal Fabrication (BBD), Electrical & Electronics (BBE) and Creative Multimedia (BBF) who took the subject BBD10803 Information Technology in Education at Universiti Tun Hussein Onn Malaysia. The results of this study indicate that the most preferred Fleming’s VARK learning style is a visual learning style

Verifikasi Desain Antena Berbasis Dipol Berbentuk V untuk Pengamatan Garis 21 Cm

21 cm adalah salah satu garis emisi penting didalam astronomi radio. Garis ini umumnya digunakan untuk mempelajari karakteristik galaksi-galaksi. Artikel ini mempresentasikan sebuah antena dipol berbentuk V untuk sistem telekop radio 21 cm, yang berkorespondensi dengan frekuensi pengamatan 1420MHz. Designnya telah diimplementasikan dan diukur. Hasil pengukuran memperlihatkan kesesuaian dengan simulasi, dengan eror frekuensi puncak sebesar 0,7%. SWR yang diperoleh juga cukup rendah, yaitu sekitar 1,14. Antena yang diajukan pada artikel ini berpotensi untuk digunakan sebagai feed pada antena reflektor atau sebagai elemen penyusun pada sebuah sistem antena array

Synthesizing Cylic Peptides with Antioxidant Properties using Solid Phase Peptide Synthesis as an Alternative to Natural Product Isolation from Pork

Tetrapeptides Ser-Leu-Tyr-Ala and Tyr-Leu-Tyr-Ala are two derivates that have been successfully isolated from the pork and synthesized using Solid Phase Peptide Synthesis (SPPS) method. Tetrapeptide Gly-Ala-Trp-Ala has also been successfully isolated from the Sardinella aurita fish found in Atlantic Ocean using SPPS. This study aims to synthesize tetrapeptide Ser-Leu-Tyr-Ala, Tyr-Leu-Tyr-Ala and Gly-Ala-Trp-Leu using the SPPS method, and to find the antioxidant properties of the synthesized tetrapeptides using DPPH test. The three tetrapeptides have been synthesized using 2-chlorotritilchloride resin as solid phase, Fmoc group protection, and coupling reagent HBTU/HOBt. HR-TOF-MS with m/z was [M+H]+ 453,23 and [2M+H]+ 905,49 for Ser- Leu-Tyr-Ala, [M+H]+114,61 for Tyr-Leu-Tyr-Ala and [M+H]+ 446,23 for Gly-Ala-Trp-Leu. The antioxidant properties of Ser-Leu-Tyr- Ala had an IC50 value of 11130,04 mg/ml, while the antioxidant properties of Tyr-Leu-Tyr-Ala had an IC50 value of 4319,522 mg/ml. Keywords: solid phase peptide synthesis, antioxidan

Lightning measurement in Sarawak, Malaysia: first results

Malaysia is one of the country with highest lightning activities in the world. Regrettably, studies on lightning characteristics is still lacking especially in the Eastern part of Malaysia, which is Sabah and Sarawak. In this study, the characteristics of electric field radiation recorded during lightning measurement campaign in Sarawak had been analyzed. The field measurement was done using parallel plate antenna attached with electronic buffer circuit. The data was recorded using a PicoScope and monitored in computer. Nineteen samples of negative first return strokes were successfully recorded during this measurement. Their electric fields waveform parameters namely peak amplitude, zero crossing time, zero to peak and 10%-90% rise time were thoroughly analyzed. All those values are 8% to 166% larger in comparison to the data obtained from lightning measurement done in the Peninsular Malaysia. It is suggested that various topology and meteorology pattern are among factors that contribute to the discrepancies

Correlation Between Cutting Force and Residual Stress in Dry End-Milling of Inconel HX

Residual stress in the end-milled subsurface can significantly affect the fatigue performance of end-milled material. In the end-milling process, the generation of residual stress is extremely complex, which is closely related to the spindle speed, feed per tooth and cutting force. Thus, it is crucial to elucidate the influence of spindle speed and feed per tooth on cutting force and residual stress, also the correlation between cutting force and residual stress in terms of spindle speed and feed per tooth. According to this, dry end-milling of Inconel HX was performed by climb-milling using Kennametal KYS40 solid ceramic end-mill. From this experimental test, cutting force and residual stress showed a U-shaped relationship with the increase of spindle speed, while cutting force and residual stress showed a linear relationship with the increase of feed per tooth. Furthermore, for low cutting force and residual stress, the focus should be on choosing the optimum combination of spindle speed (21,400 to 24,100 rpm) and feed per tooth (0.014 to 0.016 mm/tooth)

Correlation Between Cutting Force and Residual Stress in Dry End-Milling of Inconel HX

Residual stress in the end-milled subsurface can significantly affect the fatigue performance of end-milled material. In the end-milling process, the generation of residual stress is extremely complex, which is closely related to the spindle speed, feed per tooth and cutting force. Thus, it is crucial to elucidate the influence of spindle speed and feed per tooth on cutting force and residual stress, also the correlation between cutting force and residual stress in terms of spindle speed and feed per tooth. According to this, dry end-milling of Inconel HX was performed by climb-milling using Kennametal KYS40 solid ceramic end-mill. From this experimental test, cutting force and residual stress showed a U-shaped relationship with the increase of spindle speed, while cutting force and residual stress showed a linear relationship with the increase of feed per tooth. Furthermore, for low cutting force and residual stress, the focus should be on choosing the optimum combination of spindle speed (21,400 to 24,100 rpm) and feed per tooth (0.014 to 0.016 mm/tooth)

A comprehensive review of a data centre for a cooling system

Cyber-Physical-Social Systems, commercial enterprises, and social networking use data centers to store, process, and distribute massive amounts of data. A data center serves as the foundation for all of these endeavors. The data center's workload and power consumption are increasing rapidly due to the demand for remote data services. Mechanical refrigeration and terminal cooling are the most critical components for most cooling systems. There is a way to transfer heat from the data center to the outside environment, but it's a complicated process. Air cooling systems and technology are most useful for room cooling and rack-level cooling. Because of their superior cooling performance and higher energy efficiency, air cooling has attracted more attention than water cooling in most existing data centers. The chillers and fans consume the most power of all the cooling equipment in the system. These methods can be divided into mechanism-based methods and data-driven methods for energy management of the cooling system. Operation management of cooling equipment is proposed to reduce power consumption, mainly using predictive model control and reinforcement learning-based methods. An overview of the data center's cooling system is presented in this paper, which focuses on the most common cooling solutions, power consumption modeling methods, and optimization control strategies, among others. In addition, the data center's cooling system is described as a current and future issue

A training monitoring system for cyclist based on wireless sensor networks

This paper presents a training monitoring system for cyclist that is based on the technology of wireless sensor networks (WSNs). A stable and reliable wireless cyclist monitoring system is vital to establish a smart and efficient sports management program. A training monitoring system has been developed and tested in a real cyclist training environment in a velodrome. The system is designed is such a way that the packet loss rate is minimum. Using TelG mote as the basis, customized sensor nodes that function as a forwarder node and the relay nodes are developed to form the WSN. This WSN is linked to the cloud network on the Internet. The cloud network is then established and end users application for data accessing is designed. Several experiments have been conducted in a real scenario in a velodrome to measure the reliability of the system architecture. It is shown from the experiments that the proposed system is reliable even when the cyclist is moving at a high speed. The packet loss is less than 2% which does not give a huge impact to the data transmission