A wideband trapezoidal dielectric resonator antenna with circular polarization

A new design of a circularly-polarized (CP) trapezoidal dielectric resonator antenna (DRA) for wideband wireless application is presented. A single-layered feed is used to excite the trapezoidal shaped dielectric resonator to increase resonant frequency and axial ratio. Besides its structure simplicity, ease of fabrication and low-cost, the proposed antenna features good measured impedance bandwidth, 87.3% at 4.21 GHz to 10.72 GHz frequency bands. Moreover, the antenna also produces 3-dB axial ratio bandwidth of about 710 MHz from 5.17 GHz to 5.88 GHz. The overall size of DRA is 21 mm × 35 mm, which is suitable for mobile devices. Parametric study and measurement results are presented and discussed. Very good agreement is demonstrated between simulated and measured results

A supplier selection strategy within the Malaysian telecommunications industry

The telecommunication industry in Malaysia has grown rapidly over the last 15 years, with effective supply chain management becoming increasing important within the sector. A multitude of providers and part owned Malaysian government companies, vendors and suppliers are involved in generating and creating value-adding products and services within this sector (across wireless, wireline, broadband business and consumer lines of business). This paper describes key challenges facing a major telecoms service provider in Malaysia with regards to drivers involved in the overall procurement and supplier selection with regards to components of performance management, decision-making, selection techniques, quality and cost management, procurement policy and procurement ethics. This paper further focuses on defining and detailing research currently being undertaken to develop a framework for identifying supplier selection drivers that are inherent within the sector and suggests a research approach to investigate and develop strategies for supplier selection for the telecommunications industry in Malaysia

Bow-Tie Microstrip Antenna Design

In this paper, the bow-tie microstrip antennas have been designed with two different angles of 40° and 80°. An investigaton on the effect of the angle to the return loss and radiation patterns had been carried out. The impedance matching network with the niicrostrip transmission line feeding was used in this study. Simulation and measurement results for the return loss and radiation patterns were presented

Mangrove (Rhizophoro Apiculata) Fannins As A Potential Corrosion Inhibitor For Aluminium In Acidic Medium.

Utilisation of a green corrosion inhibitor formulated from natural, biodegradable and nontoxic organic compounds in industries has been extensively explored by a*great number of researchers. Investigation of tannins extracted from Mangrove Rhizophoro Apiculata sp. as a corrosion inhibitor for aluminum alloy has been carried out in acidic medium

A hedonic valuation in Putrajaya Wetlands

This study is designed to estimate the economic value of green spaces in the land of Putrajaya by using the Hedonic Pricing Method (HPM). Economic valuation regarding green spaces in Putrajaya is targeted to give an efficient solution in investment and also to facilitate the residents of Putrajaya upon the value of the environment that they received and the significance of reserving the great environment for future consumptions. Survey questionnaires were distributed to 415 respondents in Putrajaya Wetlands who lived in the housing area 2-15 Km from this park. A Hedonic Pricing Model is developed by taking housing price as the dependent variable and structural of the house including distance to the green area as the independent variables. Housing price is used as a proxy to quantify the economic value of green space. Two models (linear model and semi-log model) mainly based on hedonic price model are formulated and regressed through ordinary least square (OLS) method. In term of model comparison, the result revealed that semi-log model (Model 2) performed better than the linear model (Model 1). As expected, a significant inverse relationship between the housing price and its distance from the residential area and the Putrajaya Wetland has been found whereby a slight decrease of 1 Km of the distance will positively increase the housing price by 5.9%. The result positively shows that the green space has contributed indirectly towards the housing price and it indicates that green space is a vital part of urban development in the city area. In conclusion, the green space provides benefits especially regarding its economic value. Thus, conserves and preserve in maintaining this area is ought to be implemented

Pengaruh Berbagai Jenis Bokashi terhadap Serapan Fosfor Tanaman Jagung Manis (Zea Mays Saccarata)

The aim of this research is to determine the effect of various types of bokashi on phosphorus uptake of sweet corn crops. The research was conducted in the village of Sidera, District Biromaru, Sigi, Central Sulawesi Province. Analysis of soil, plant tissue and bokashi performed in the Laboratory of Soil Science, Faculty of Agriculture, University of Tadulako, Palu. This research was arranged in Randomized Block Design (RBD), which consists of 7 treatments and replicated 3 times so that there are 21 experimental units. Treatment that consists of control and 6 types of biomass materials of gamal, venus, peanuts, chicken manure, goat manure and cow dung, each is used as much as 15 t ha-1. The results showed that application of various types of bokashi with a dose of 15 t ha-1 increased C-organic of soil, soil pH, total P, available P and phosphorus uptake of plant sweet corn. HSD test results (5%) indicate that P uptake is highest in bokashi treatment gamal (6,74g/plant) were significantly different with bokashi treatment peanuts (3,34 g/plant), bokashi venus (3,05 g/plant), bokashi goat manure (3.01 g/plant), bokashi cow manure (1.62 g/plant), bokashi chicken manure (0,96 g/plant), and control (0,28 g/plant). In the treatment of peanut bokashi no real difference in bokashi venus and goat manure but all three types are significantly different bokashi cow manure, chicken manure and control

Serological prevalence of leptospiral infection in wild rats at the National Service Training Centres in Kelantan and Terengganu

One hundred and sixty eight rats were trapped from the National Service Training Centres (NSTC) in Kelantan and Terengganu from October 2008 to May 2009. Microscopic agglutination test (MAT) was performed to detect the presence of agglutinating antibodies to Leptospira among the rats caught. All the MAT positive rats were identified as Rattus tiomanicus. In Kelantan, 17.3% (14/81) of the rats had leptospiral antibodies to serovars Icterohaemorrhagiae (12.3%), Canicola (2.5%), Ballum (1.2%), and Pyrogenes (1.2%). In Terengganu, 18.4% (16/87) of the rats had antibodies to serovars Icterohaemorrhagiae (15%), Canicola (1.1%), Pyrogenes (1.1%) and Hebdomadis (1.1%). This study indicated that Leptospira serovars were prevalent in the rat population in the study areas and could be a source of infection to humans. Therefore, control of the rat population in all NSTC is critical to prevent outbreaks of leptospirosis amongst the NSTC trainees

Hidrolisis Selulosadari Bahan Pod Husk Kakao Menggunakan Asam Klorida

The aims of this experiment were to obtain the best concentration of HCl and the optimum length of boiling time in producing liquid sugar from cacao pod husk. Analysis of data of extracted cellulose (Phase I) used completely randomized design (CRD), which consisted of 3 NaOH concentrations tested namely : 10%, 12% and 14%. Each treatment was replieated 4 times, and therefore there were 12 experimental units used. Analysis of variance showing significant or highly significant effects were subsequently analysed by HSD at 5% or 1%, respectively. Experimental design used in the hydrolysis of cellulose (Phase II) was randomized block design (RBD) with four levels of hydrochloric acid (HCl) tested, namely: K1 = 1%; K2 = 1.5%; K3 = 2% and K4 = 2.5%. Treatments were grouped based on the length of pod husk cellulose hydrolysis time in hydrochloric acid solution, namely R1 = 2 hours, R2 = 4 hours, R3 = 6 hours, R4 = 8 hours, R5 = 10 hours and R6 = 12 hours. Each treatment was replicated three times in each group, and therefore there were 72 experimental units observed. Analysis of variance showing significant or highly significant effects were subsequently analysed by HSD at 5% or 1%, respectively. The best NaOH concentration was obtained at 12% and the optimum length of boiling time was 8 hours

Pembuatan Minuman Instan Fungsional dari Bioaktif Pod Husk Kakao

This research consists of two stages in which the first stage aims to find out the weight of the best cocoa pod husk powder that can be produced instant cacao pod husk beverages. The results of the analysis of the antioxidant capacity levels of total phenol showed that the use of dried cocoa pod husk by ethanol solvent has the highest level of both total phenols and antioxidant capasity. The second phase activity aims to find out the levels of total phenols and antioxidant capacity of instant beverages from various extracts of cocoa pod husk. This study used a completely random design (CRD) with one factor which was consisting of four levels namely cocoa pod husk weight 5 g, 10 g, 15 g and 20 g. Maltodextrin 20 g and 10 g of sucrose was added to thicker the instant beverage. The analysis showed that the highest of total phenols and antioxidant capacity in the drink when used 20 g of cocoa pod husk. The best phenols and antioxidant capacity content was from 10 g cocoa pod husk extratraction thus this amount has to be used as standard to produce this instant drink