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The radio signal transmitted by the Mars Express (MEX) spacecraft was observed regularly between the years 2013-2020 at X-band (8.42 GHz) using the European Very Long Baseline Interferometry (EVN) network and University of Tasmania's telescopes. We present a method to describe the solar wind parameters by quantifying the effects of plasma on our radio signal. In doing so, we identify all the uncompensated effects on the radio signal and see which coronal processes drive them. From a technical standpoint, quantifying the effect of the plasma on the radio signal helps phase referencing for precision spacecraft tracking. The phase fluctuation of the signal was determined for Mars' orbit for solar elongation angles from 0 - 180 deg. The calculated phase residuals allow determination of the phase power spectrum. The total electron content (TEC) of the solar plasma along the line of sight is calculated by removing effects from mechanical and ionospheric noises. The spectral index was determined as $-2.43 \pm 0.11$ which is in agreement with Kolomogorov's turbulence. The theoretical models are consistent with observations at lower solar elongations however at higher solar elongation ($>$160 deg) we see the observed values to be higher. This can be caused when the uplink and downlink signals are positively correlated as a result of passing through identical plasma sheets., The paper has 13 figures and one table. It has been accepted for publication in PASA and the article will receive its DOI in a week's time

The atom-bond connectivity (ABC) index is one of the recently most investigated degree based molecular structure descriptors that have applications in chemistry. For a graph G, the ABC index is defined as ABC(G) = ∑ uv∈E(G) [ d v + d u −2]/[ d v · d u ], where du denotes the degree of a vertex u in G. In this paper, we establish the general formulas for the atom bond connectivity index of molecular graphs of alkynes and cycloalkynes.

Sedimentation due to gravitation is applied extensively in water and wastewater treatment to remove suspended solids. Suitable baffle configurations may help form favorable flow fields and increase the efficiency of a primary sedimentation tank. Experimental tests were performed to determine the best position for a baffle in a rectangular primary sedimentation tank. The experimental measurements consisted of three parts. First, the velocity fields were measured using an acoustic Doppler velocimeter. The concentration at different vertical and horizontal points was then evaluated. Finally, the removal efficiency of the sedimentation tank was measured. The results of the present study indicate that a uniform flow field in the settling zone is enhanced when the baffle position provides a small volume of circulation regions. In this case, the maximum concentration of the suspended sediments inside the settling zone and the highest removal efficiency are achieved.

Green curb was introduced to be an alternative material for a traditional road curb. This green curb is having a different concrete mix but the dimension and other requirement with respect to JKR requirement is still the same. The coarse aggregate will be replaced with crumb rubber (CR) that was extracted from vehicle tires after been shredded to the specified size from 15-20 mm as coarse aggregate. Testing such as slump test, compressive strength test and rebound hammer test was conducted to obtain the results. From the results, the slump test shows a high workability and decrease in compressive strength as the percentage of CR increase. The total weight of road curb is reduced by almost 8% compared to the control specimen. This 20% CR mixtures shows good result among other mixtures. The percentage of CR used are 20%, this particular percentage has good workability, satisfy the concrete grade 25 as required by JKR guideline (JKR/SPJ/1988).

Undular hydraulic jumps are illustrated by a smooth rise of the free surface followed by a train of stationary waves. They are sometimes experienced in natural waterways and rivers. The characteristics of undular hydraulic jumps are studied here. The height, amplitude and the main characteristics of undular jump is depended on the upstream Froude number and aspect ratio. The experiments were done on the smooth bed flume. These results compared with other researches and the main characteristics of the undular hydraulic jump were studied in this article.

Extended Kalman Filter (EKF) has been successfully utilized in a number of satellites. However, compared to other attitude determination methods developed, it is one of the most computationally burdening algorithm and with the new trend of using nano-satellites which have limited electrical power, mass, space and usually budget, it is essential to design an attitude determination system (ADS) which conforms to this limitation. Therefore, in this paper, as an improvement on the InnoSAT project which incorrectly runs the EKF algorithm on the RCM3400, the CPU is replaced with the ARM7TDMI microprocessor to successfully perform attitude determination of InnoSAT using the EKF. The ARM7TDMI has been chosen since it is one of the well-known microprocessor used in various electronic equipment because it is low power and robust. It is also off the shelf which means it is easily available thus making it a cheaper solution than a space grade component. Analysis on the ARM7TDMI was done based on attitude data accuracy and execution time.

In this study, a fuzzy clustering method that we implemented in statistical software package (XploRe), GIS (GRASS) and remote sensing (ERDAS) were used to classify and preset multi-spectral Landsat TM images. Comparatively, the result of this investigation shows that the underlying structures and patterns from satellite images data can be classified more precisely than the conventional ones.

This paper describes the aerospace activities in Malaysia especially in the areas of space technology. The recent satellite based activities in Malaysia had made the need for human resource development and aerospace research based activities more prominent. The efforts done by Universiti Sains Malaysia to meet this need is described. Apart from the academic programs planned, research and development activities are also described in which it was designed to meet the national satellite and space programme and also support supporting aerosapce industries with the assistance from various parties.