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This article reviews the subject of entrepreneur with a focus on the components of the entrepreneurial personality traits that are reflected in entrepreneur behaviour. Human behaviour receives a warm welcome in social psychology for examination and measurement of individual social behaviour. There are a number of tools to measure human behaviour in social science such as Likert scale, Indices, Social Network Analysis, E-scan and lastly most popular Big Five Factor Model. In entrepreneurship, entrepreneur’s personality can be reflected in their action, activity, and behaviour in certain space such as traveling to find raw resources in certain distance or their decision on size of the shop. Using in-depth observation and examination of this behaviour, there are several spatial elements that could lead to the possibility in implementing spatial measurement in entrepreneur behaviour. However, there is a scarcity of research and implementation of the spatial measurement on entrepreneur behaviour, even though it is already acknowledged that space influences human behaviour and vice versa human behaviour has an impact on space. Thus, this article aims to highlight the possibility of implementing spatial measurement in entrepreneur behaviour and current exploration of spatial measurement for human behaviours.

In this paper, we propose a new adaptive layered asymmetrically-clipped optical orthogonal frequency division multiplexing (ALACO-OFDM) technique as a method to improve the spectral efficiency of optical system, especially visible light communication (VLC). Particle swarm optimisation (PSO)-based LACO-OFDM method is used for this purpose and the channel capacities are studied. Simulations using variable layers are carried out to validate the theoretical steps. The simulation results indicate that the ALACO-OFDM technique has significantly improve the spectral efficiency compared to previous techniques such as ACO-OFDM. Moreover, it is shown that channel capacities of different layers are significantly improved when electrical power is increased.

Distal oesophageal spasm is a rare condition that affects the motility of the oesophagus. It can be diagnosed by highresolution oesophageal manometry and the diagnosis is supported by other modalities such as barium swallow and esophagogastroduodenoscopy examinations. Treatment options include pharmacological therapy, endoscopy and surgical interventions. We described a case of distal oesophageal spasm in an elderly patient who presented with chronic dyspepsia.

We propose a modified OFDM modulation based on multiband scheme for visible light communications (VLC) system. The method called catenated-OFDM VLC system can efficiently boost the propagation distance and combat multipath induced the inter symbol interference and inter carrier interference. Design parameters such as number of optical bands, input power, distance and data rate are varied to see their effect on the system performances. Simulation analysis is done using Optisys software Ver. 11.0. The results show that the proposed system offers a good performance at longer transmission distance of 12 m for input power of 2 dBm in case of Band=3 with 10 Gbps data rate. BER curves also indicates that the proposed system can be operated at very high data rate of 15 Gbps. This exhibits the ability of the proposed system to be one of the candidate for future optical wireless communication system.

The number of students pursuing science and engineering is reducing drastically over the years which is of great concern to the country. Hence, in 2011, the Malaysia Education Blueprint was initiated emphasizing on the role of STEM for establishing a scientific and innovative society. The National STEM Movement has taken the step forward to make the blueprint a reality by initiating the STEM Mentor-Mentee program in schools facilitated by universities. Universiti Selangor (Unisel) contributed actively through the participation of lecturers as facilitators and students as mentors. Fondly known as the Unisel Fun with STEM program, the team has shared their modules with seven schools in Selangor. This particular study is focusing on one of the schools, SMK Sungai Burong involving 60 students and 3 teachers, assessing the effectiveness of the module and the impact of mentoring approach. A five Likert scale survey was conducted at the end of the program with each of the four domains received positive feedback. The program itself was well-executed with the mean score of 4.24. The response towards the mentoring approach was very favourable, resulting in the mean score of 4.61. This outreach program is considered effective as students demonstrated positive attitude towards the module and STEM field.

Visible light communication (VLC) technology offers unregulated, unlicensed and huge bandwidth to meet the growing demand in future indoor communication system. One of the major challenge in VLC system is in improving transmission speed with optimize the bandwidth capacity. The method to improve spectral usage is using advanced modulation formats such as orthogonal frequency division multiplexing (OFDM). In this work, a new approach for modulation technique based on multiband OFDM has been developed which capable to improve the spectral efficiency and optimize the data rate. A proposed technique is then adapted in OCDMA-VLC environment to analyse the reliability of the proposed scheme in high capacity network. Different selection of parameter values such as bit rates, number of bands and effective received power will have different effect on the system performance. Numerical result shown that the catenated-OFDM outperforms conventional OFDM by five times spectral efficiency improvement and eight times spectral efficiency improvement at their five and eight number of bands respectively. It is also shown that the proposed catenated-OFDM design is working well even at very high bit rate of 15 Gbps. Moreover, there are enhancement in receiver sensitivity with 7.3 dB power penalty compared to previous work.

Diffusers transmitter modulation to reduce the effect of atmospheric turbulence in free space optical communication system is described in this paper. This technique uses dual transmitters and dual receivers which are using differential mode for detection. The combination of these components produce superior modulation method especially to reduce scintillation index, to overcome signal detection with fix zero threshold and improve power received. In order to improve the performance of free space optical system, these three elements play an important role. The analysis result show that for receiving power dual diffuser modulation at 3 km distance propagation is 4.59dBm compared to conventional OOK using diffuser which only −7.6dBm and equivalent to 3dBm improvement or up to 40 percent better.

A new dual-diffuser modulation (DDM) technique improve the performance of the conventional intensity modulation/direct detection (IM/DD) for On Off Keying (OOK) in term of data bit rate and propagation distance. This new modulation technique employs two transmitters and two receivers to create a robust modulation with optimizing the reduction scintillation index, enhance the power received and improve the threshold signal level. At the transmitters, the laser exits combine with low cost phase screen diffuser to create a ‘new’ superior laser beam characteristic in order to combat atmospheric turbulence effectively. Meanwhile at the receivers, the signal will be subtracted. The analysis result shows that in comparison various data bit rates at BER10−9, the DDM is capable to operate excellent under small power launched where the bit rate can achieved above 10Gbps at 5dBm power transmit. Meanwhile for phase screen diffuser effect, the DDM optimizes the performance of diffuser where the data bit rate can reached approximately 1.5Gbps and the conventional IM/DD-OOK only performed at 0.155Gbps.

Dense wavelength division multiplexing system is a system for coupling and transmitting the optical signals at different wavelength through the single fiber. Such technology is important in order to increase the capacity in optical communication system and to meet the growing demands of bandwidth. However, there are some limiting factors related to the data rate and capacity in this system. These limiting factors can be linear or nonlinear. Theoretically, the nonlinearities in fiber arise as the number of data channel, transmission length, data rate and input power level increase. In this project, the objective is focused towards analyzing on the nonlinearities effect by compensating the linear effect in the fiber. Dispersion Compensation Fiber (DCF) and linear loss EDFA compensation have been used in single mode fiber (SMF) channel to ensure the communication quality for the design. The proposed dispersion compensation DC-DWDM transmission system with 16 and 32 channels for 10Gbps with a channel spacing of 0.8nm was designed and simulated. The BER performance with various input power levels in the range of −10dBm up to 10dBm, and fiber length greater than 50km are analyzed. It has been shown that for fixed length of the fiber, the only variable that can be manipulated to lower the nonlinear contribution is the input power. The higher the input power the higher the nonlinear contribution. However, if the input power is low, the bit rate should be low to maintained transmission at the expected BER (BER < 10–12)

Switchable parasitic antennas in realizing beam steering ability is proposed. This is achieved by forming four similar parasitic encircling a single driven element. Each of the parasitic has been shorted to the ground via a shorting pin maintaining the frequency resonant at 2.38 GHz. Two different type of switches are used;HPND-4005 PIN Diode and RMSW101 MEMS switches. Each of the switches is employed at specific locations in the parasitic to change its effective electrical length hence forming a reflector and director. Both antennas have a capability to steer beam at five modes angle. The proposed antennas is functioning for WiMAX (2.36-2.39 GHz) application. Both antennas performance are discussed in details.

This paper proposes an integration of optical Code Division Multiple Access (OCDMA) with new catenated Orthogonal Frequency Division Multiplexing (OFDM) modulation scheme. This effective combination based on Zero Cross Correlation (ZCC) code can enhanced the system capacity and increased spectral efficiency by fully utilizing the available electrical bandwidth. We investigate the performance of the proposed system for various number of user, number of weight and effective power. The performance assessment is carried out by means of the signal to noise ratio (SNR) and bit error rate (BER) for up to five catenated OFDM bands transmitted simultaneously through optical link at 622 Mbps. More specifically, mathematical expressions for SNR and BER performance are derived. The corresponding numerical results are presented and compared with traditional OCDMA-ZCC system to verified the feasibility of the proposed system. The results show that with OCDMA/catenated-OFDM based on ZCC code provides 86% more number of permissible user for SNR of 15 dB. In addition, this integration provides higher receiver sensitivity; an approximately –22.5 dBm for 20 number of user with 8 number of weight. It is also found that, to accommodate more user, the system requires higher effective power at the receiver.

Lembah Bujang is one of Peninsular Malaysia’s most important areas for archaeology as excavations in this area have revealed many traces of Malaysia’s prehistory. The site is one of the oldest known place human activities the Peninsula. The aim of this study is to map and understand the subsurface structure of the survey area which is one of the archaeologically interesting areas. Geophysical methods are used because it is nondestructive and do not disturb the site. The methods are relatively quick and the results are used as a guide for subsequent excavation work. So it can greatly help in setting the digging priorities as geophysical surveying can reveal, for instance, important subsurface features like monuments, tunnels, voids, or buried walls. The geophysical methods used in this study were the magnetic gradiometer, 2‐D electrical resistivity and ground penetrating radar (GPR) method. The integration of these three methods can be beneficial as each method has its strength and limitation. The specific area of study is in Sungai Batu and the results show that the sedimentation consists of sandy clay, alluvium and boulders with a depth of between 0 m to 15 m.

Sinkholes, cavities, boulders and faults in rock and soil could lead to major engineering and environmental problems. Resistivity variation is an important property in shallow subsurface investigation. Resistivity values of rock and soil are severely affected by pore connectivity and fluid type. Resistivity method is one of the geophysical surveys employed to map the subsurface structures. Resistivity data was collected using three different arrays (Wenner, Wenner‐Schlumberger and Pole‐dipole) on the homogenous ground with 5 cm electrodes spacing. Subsequently, two identical square holes (20 cm ×7 cm ×30 cm ) were made 10 cm below the ground surface and 20 cm apart. The resistivity data was collected again using the three different arrays across the two holes. The result for the homogenous ground shows a low resistivity value, while the homogenous ground with holes show high resistivity value around the holes. The results of the three arrays are then compared. The Pole‐dipole array produced the best image of the two holes with a deeper depth of penetration.

Geophysical surveys (2‐D resistivity imaging and seismic refraction) were conducted in Tanjung Tokong, Penang and Gunung Keriang, Kedah. Tanjung Tokong is a reclaimed area which is under construction for building 24 floors moderate apartment. Subsurface boulders and unknown materials in reclaimed layer have caused problems in construction of the structural foundation in the area. The objective of the study at Tanjung Tokong is to obtain subsurface information that include the depth to bedrock, boulders, composition of subsurface structures and to map the flow of subsurface water by using 2‐D resistivity imaging and seismic refraction method. Gunung Keriang is a limestone area with karst characteristics such as cavity and pinnacle. These features may be a threat to human’s life and could cause damage to properties. The objective of the study at Gunung Keriang is to detect cavities, pinnacles, fractures and void that may formed in limestone area by using 2‐D resistivity imaging method. In Tanjung Tokong, the subsurface consist of two layers. The first layer refers to the reclaimed land with mixture of boulder. The second layer has saltwater intrusion and granite bedrock at 17 meter depth. In Gunung Keriang, the cavity was detected at 180 meter in survey Line 2 while two pinnacles were detected at 80 meter and 170 meter in survey Line 3. Both geophysical methods were used successfully in providing subsurface information to the engineers.

Groundwater is a very important component of water resources in nature. Since the demand of groundwater increases with population growth, it is necessary to explore groundwater more intensively. In Malaysia only less than 2% of the present water used is developed from groundwater. In order to determine the existence of usable groundwater for irrigation and drinking purposes in Pagoh, 2D resistivity imaging technique was utilized. The 2‐D resistivity imaging technique utilized the Wenner—Schlumberger electrode array configuration because this array is moderately sensitive to both horizontal and vertical structures. Three lines were surveyed for groundwater delineation purpose The length for each survey lines are 400 meters. At Pagoh, the survey site shows the existence of groundwater. It is indicated by the resistivity values about 10–100 ohm‐m. The maximum depth of investigation survey is 77 meters. In general the results show that the subsurface is made up of alluvium and clay and the high resistivity values of more than 1000 ohm‐m near the surface is due laterite and the end of the depth can be interpreted as mixture of weathered material or bedrock.

Surface water is critically important in supplying water to streams and wetlands, and in providing water for irrigation, manufacturing, electricity power and other uses and it is an important source of water supply especially in various regions in Malaysia and it become ever more important with an increasing population. However groundwater can be an alternative source of water to the ever increasing population. Groundwater is water located beneath the ground surface in soil pore spaces and in the fractures of lithologic water formations. This would provide alternative freshwater source. In order to determine the existence of usable groundwater for agriculture purposes in Marang Terengganu, 2‐D resistivity imaging technique was utilized. Three lines were surveyed at the site. The 2‐D resistivity imaging technique utilized the Pole ‐dipole array because of relatively good horizontal coverage but it has significantly higher signal strength. The total length of the survey lines is 400 meters. Three lines were surveyed for groundwater delineation purpose. At Marang, the survey site shows the existence of groundwater. The maximum depth of investigations for the surveys is 125 meters. In general the results show that the subsurface is made up of sand and clay (resistivity value of less 100 ohm‐m) and sandstone with resistivity of more than 2000 ohm‐m in all the sections. This zone can be a source of groundwater.

The two-dimensional (2-D) resistivity imaging technique (Griffith and Barker, 1993) was successfully used to map subsurface voids and other near-surface structures. As an example, the results from a test survey in the Universiti Sains Malaysia campus to locate drainage and sewage pipes are discuseed. A comparison study, between the anomalies due metal pipe and concrete pipe was conducted.