Development of Mission Control Unit Prototype for Small Class Satellite Payloads

In this paper, Mission Control Unit (MCU) prototype for small class satellite payloads is developed with the goal of providing schools and institutions to low cost design that could be easily integrated and augmented for mission–specific needs. Basic design platform has been developed to demonstrate the proof of concept model of MCU for small satellites by using commercial off-the-shelf (COTS) components. Many commercial companies have emerged to cater this objective however most of them provide expensive on-the-shelf solution, therefore this paper proposed a low cost, compact platform design. This paper presents the design of payload-ready prototype unit of mission control subsystem that is built on Arduino based microcontroller with wireless transmission by using COTS components. This platform is intended mainly for educational purposes, specifically to expose high school and university students or researchers to satellite engineering concept. Other than that, it is developed to provide platform for spacecraft developers, researchers and others to test their scientific missions or perform their research with reduced costs. In addition, the end-product of this project can be used for public outreach mission involving local communities of amateur radio operators and school students. This project has produced a prototype that is compatible with 2U CubeSat platform standard, requires no external wiring with all subsystems, and can be customized to perform many mission themes over amateur radio band

Analysis on Wearable Antenna Performance on Different Radiating Elements for GPS Application

This paper presents a study on the performance of self-manufactured electro-textile (SME-T) antenna that was designed at 1.575 GHz based on the allocated spectrum for Global Positioning System (GPS) application. However, due to its known low-conductivity characteristic, the ability of the newly developed material to perform as a good antenna shall be verified. Therefore, the performance of the antennas are compared and studied with respect to established materials such as adhesive copper tape and commercial conductive fabric named SHIELDITTM as the radiating elements. Here, four e-textile antennas having approximately the same size are fabricated and tested. The performance of all antennas, in terms of return loss, radiation pattern, gain, and efficiency; manufactured by using different radiating elements, such as copper, SHIELDITTM and SME-T fabricated on polyester fabric as the substrate are analyzed. The measured return loss and radiation pattern of SME-T antenna has proven that the antenna is well suited for wearable application. The measured antenna gain and efficiency of 0.61 dB and 25.95% are obtained and it is proven that the fabricated SME-T antenna can act as a receiving antenna designed for GPS applications which requires low gain antenna for passive monitoring

Optoelectronic properties comparison of 10 and 20 multi quantum wells Ga0.952In0.048N0.016As0.984/GaAs p-i-n photodetector for 1.0 µm wavelength

This study proves the addition of quantum wells to the intrinsic regions of p-i-n GaInNAs/GaAs has improved the performance of optoelectronic devices. The optoelectronic properties that contribute to the device's dark current and photocurrent need to be well understood to develop photo-response at longer wavelengths. This study reports an optoelectronic properties comparison of different quantum well number for Ga0.952In0.048N0.016As0.984/GaAs-based dilute nitride multi-quantum wells (MQWs) p-i-n photodetector devices. From photoluminescence (PL) analysis, 20 MQWs shows a higher PL peak than 10 MQWs. The maximum quantum efficiency (QE) is found to be 80.3% for 20 MQWs and 46% for 10 MQWs, where 20 MQWs being the highest QE value ever reported for GaInNAs-based MQWs photodetector. Current versus voltage (I–V) measurement shows that 20 MQWs produces lower dark current than 10 MQWs. Besides, 20 QWs sample produces a higher current density (−12.43 μAcm−2) than 10 MQWs (−7.52 μAcm−2) under illumination. Impedance spectroscopy analysis shows that a lower dark current of 20 MQWs is due to a high intrinsic resistivity and low dielectric loss peak compared to 10 MQWs. SimWindows simulation shows good correlation with responsivity analysis and impedance analysis where at −5 V, 20 MQWs produces higher responsivity (0.65AW-1) due to wider depletion region (deduce from conduction band profile) and lower intrinsic capacitance and dielectric loss (deduces from impedance analysis) than 10 MQWs (0.37AW-1). At room temperature, the detectivity (D*) of the 20 MQWs photodetector (7.12 × 1010 cmHz0.5W−1) is higher than 10 MQWS photodetector (4.89 × 1010 cmHz0.5W−1). Finally, the 20 MQWs's (4.02 × 10−11 WHz−0.5) has produces lower noise-equivalent power (NEP) than 10 MQWs (5.85 × 10−11 WHz−0.5). This study has successfully presenting an understanding of optoelectronic properties and simultaneously producing a sensitive photodetector with high quality, low-noise which is comparable with ∼1010 cmHz0.5W−1 of commercial III-V alloy based near-infrared GaAs-based photodetectors

The Development of Ball Control Techniques for Robot Soccer based on Predefined Scenarios

Robotic soccer is an attractive topic in artificial intelligence and robotics research. However, to develop techniques and algorithms in this domain is a complex task. This study presents the development of ball control techniques and algorithms for robot soccer based on several predefined scenarios. In this study, we study the robot can do ball passing, obstacle avoiding and ball shooting according to certain situations. A vision system is used in this case where it calculates the robot position in x, y coordinates to make sure the robots move to the right direction. The velocity of each robot wheel is manipulated to control the speed of the robots and allow them to make turning and shooting. Algorithm testing was carried out by using a robot soccer simulator. Several techniques in obstacle avoiding and positioning were successfully implemented. The results prove these algorithms can be applied to execute the given tasks. © 2011 Asian Network for Scientific Information

Age at first birth in women is genetically associated with increased risk of schizophrenia

Prof. Paunio on PGC:n jäsenPrevious studies have shown an increased risk for mental health problems in children born to both younger and older parents compared to children of average-aged parents. We previously used a novel design to reveal a latent mechanism of genetic association between schizophrenia and age at first birth in women (AFB). Here, we use independent data from the UK Biobank (N = 38,892) to replicate the finding of an association between predicted genetic risk of schizophrenia and AFB in women, and to estimate the genetic correlation between schizophrenia and AFB in women stratified into younger and older groups. We find evidence for an association between predicted genetic risk of schizophrenia and AFB in women (P-value = 1.12E-05), and we show genetic heterogeneity between younger and older AFB groups (P-value = 3.45E-03). The genetic correlation between schizophrenia and AFB in the younger AFB group is -0.16 (SE = 0.04) while that between schizophrenia and AFB in the older AFB group is 0.14 (SE = 0.08). Our results suggest that early, and perhaps also late, age at first birth in women is associated with increased genetic risk for schizophrenia in the UK Biobank sample. These findings contribute new insights into factors contributing to the complex bio-social risk architecture underpinning the association between parental age and offspring mental health.Peer reviewe

Mandibular third molar and angle of mandible fractures: an unsolved clinical dilemma

The purpose of this study was to investigate the relationship between partially erupted impacted mandibular third and the risk for angle of mandible fracture. We designed a retrospective cohort study composed of patients who presented with mandible fractures. The predictor variables were the presence and angulation of the partially erupted impacted mandibular third molar and the distance between the apices of the mandibular third molar and the inferior border of the mandible. The outcome variable was the presence or absence of an angle fracture. Patients with a partially erupted impacted mandibular third molars had a 3.3 times greater chance of an angle fracture than patients without mandibular third molars (p<001). No significant association was found between the distance of the apices and angulation of the mandibular third molars to the inferior border of the mandible with angle of mandible fractures. Our findings highlight the need for enforcement of proper protective gear in young individuals who are at high risk for facial trauma

Analysis on Wearable Antenna Performance on Different Radiating Elements for GPS Application

This paper presents a study on the performance of self-manufactured electro-textile (SME-T) antenna that was designed at 1.575 GHz based on the allocated spectrum for Global Positioning System (GPS) application. However, due to its known low-conductivity characteristic, the ability of the newly developed material to perform as a good antenna shall be verified. Therefore, the performance of the antennas are compared and studied with respect to established materials such as adhesive copper tape and commercial conductive fabric named SHIELDITTM as the radiating elements. Here, four e-textile antennas having approximately the same size are fabricated and tested. The performance of all antennas, in terms of return loss, radiation pattern, gain, and efficiency; manufactured by using different radiating elements, such as copper, SHIELDITTM and SME-T fabricated on polyester fabric as the substrate are analyzed. The measured return loss and radiation pattern of SME-T antenna has proven that the antenna is well suited for wearable application. The measured antenna gain and efficiency of 0.61 dB and 25.95% are obtained and it is proven that the fabricated SME-T antenna can act as a receiving antenna designed for GPS applications which requires low gain antenna for passive monitoring