Development Of A Semi-Swath Craft For Malaysian Waters

Small Waterplane Area Twin Hull (SWATH) and Catamaran vessels are known to have more stable platform as compared to mono-hulls. A further advantage of SWATH as compared to Catamaran is its smaller waterplane area that provides better seakeeping qualities. However, the significant drawback of the SWATH vessel is when encountering head-sea at high forward speed. Due to its low stiffness, it has a tendency for large pitch motions. Consequently, this may lead to excessive trim or even deck wetness. This phenomenon will not only degrade the comfortability but also results in structural damage with greater safety risks. In this research a modified SWATH design is proposed. The proposed design concept represents a combination of Catamaran and SWATH vessel hull features that will lead to reduce in bow-diving but still maintains good seakeeping capabilities. This is then called the Semi- SWATH vessel. In addition, the full-design of this vessel has been equipped by fixed fore fins and controllable aft fins attached on each lower hull. In the development of controllable aft fins, the PID controller system was applied to obtain an optimal vessel’s ride performance at speeds of 15 (medium) and 20 (high) knots. In this research work, the seakeeping performance of Semi-SWATH vessel was evaluated using time-domain simulation approach. The effect of fin stabilizer on the bare hull performance is considered. The validity of numerical evaluation was then compared with model experiments carried out in the Towing Tank at Marine Technology Laboratory, UTM. It is shown that the Semi-SWATH vessel with controllable fin stabilizer can have significantly reduction by about 42.57% of heave motion and 48.80% of pitch motion

Quantum-secured imaging

We have built an imaging system that uses a photon's position or time-of-flight information to image an object, while using the photon's polarization for security. This ability allows us to obtain an image which is secure against an attack in which the object being imaged intercepts and resends the imaging photons with modified information. Popularly known as "jamming," this type of attack is commonly directed at active imaging systems such as radar. In order to jam our imaging system, the object must disturb the delicate quantum state of the imaging photons, thus introducing statistical errors that reveal its activity.Comment: 10 pages (double spaced), 5 figure

Computer Simulation of Current Forces on Motion of Floating Production Storage and Offloading in Irregular Waves

This paper presents the effect of current forces on the motion of forces on Floating Production Storage and Offloading (FPSO) in irregular waves. The objective of this research is to compute the motion of FPSO in irregular waves by time domain simulation including the effect of current forces. A study is made on the slowly varying oscillations of a moored single body system in a current and waves. Linear potential theory is used to describe the fluid motion, and three-dimensional source distribution techniques are applied to obtain the hydrodynamic forces and transfer function of the wave exciting forces. OCIMF (1994) data are used for estimation of the current forces. The non-linear time domain simulations have been carried out in irregular waves. Based on it, slowly varying motion responses are examined including the effect of the current forces. Several environmental conditions, such as the current angle of attack, current velocity, significant wave height and mean wave period are considered, which may significantly affect FPSO motion in surge, sway and yaw moments. It is found that the effect of current forces is quite significant when the current velocity is increased. In this simulation, while the current velocity is increased to 3.0 meter/seconds, the impact on FPSO motion is quite significant, which should be taken into consideration from the point of view of safety, failure of mooring systems, operating responses and the dynamic positioning of the FPSO

HEXOSYS II - Towards realization of light mass robotics for the hand

This research presents a prototype of a direct-driven, optimized and light-mass hand exoskeleton that is designed to fit over the dorsal side of the hand, thus retaining palm free for interaction with real/virtual objects. The link lengths of the proposed Hand EXOskeleton SYStem (HEXOSYS) TT have been selected based on an optimization algorithm. In an attempt to make the design human hand compatible, the actuators of HEXOSYS II have been chosen as a result of series of experiments on human hands of various sizes. The system based on an optimum under-actuated mechanism provides 3 DOF/finger. The resultant motion of the exoskeleton allows the wearer to perform flexion/abduction as well as passive abduction/adduction. Simple and under-actuated mechanisms together with compact mechanical design lead to realize a light mass robotic system. The first prototype of HEXOSYS II has been fabricated. Comprising of four fingers, which are enough to accomplish most of our daily life activities, the system weighs 600 grams. © 2011 IEEE

Compressive Object Tracking using Entangled Photons

We present a compressive sensing protocol that tracks a moving object by removing static components from a scene. The implementation is carried out on a ghost imaging scheme to minimize both the number of photons and the number of measurements required to form a quantum image of the tracked object. This procedure tracks an object at low light levels with fewer than 3% of the measurements required for a raster scan, permitting us to more effectively use the information content in each photon.Comment: 10 pages, 4 figure

Rapid Generation of Light Beams Carrying Orbital Angular Momentum

We report a technique for encoding both amplitude and phase variations onto a laser beam using a single digital micro-mirror device (DMD). Using this technique, we generate Laguerre-Gaussian and vortex orbital-angular-momentum (OAM) modes, along with modes in a set that is mutually unbiased with respect to the OAM basis. Additionally, we have demonstrated rapid switching among the generated modes at a speed of 4 kHz, which is much faster than the speed regularly achieved by spatial light modulators (SLMs). The dynamic control of both phase and amplitude of a laser beam is an enabling technology for classical communication and quantum key distribution (QKD) systems that employ spatial mode encoding

Endostatin concentration in plasma of healthy human volunteers

Background: Angiogenesis is involved in many cardiovascular and cancerous diseases, including atherosclerosis and is controlled by a fine balance between angiogenic and angiostatic mediators. Endostatin is one of the main angiostatic mediators, and inhibits angiogenesis and prevents progression of atherosclerosis. The available literature shows a broad range of concentrations in relatively small samples of healthy controls and is calculated by using different techniques. This study was aimed to determine the basal endostatin concentration in plasma of healthy volunteers, to fully understand its physiological role. Methods: Fifty healthy adult volunteers were recruited to the study. Participants were advised not to participate in any physical activity on the day before the blood sampling. The volunteers’ physical activity, height, weight, heart rate and blood pressure were recorded. The samples were analysed for plasma endostatin concentration, using ELISA. The participants were divided by gender and ethnic groups to calculate any difference. Results: Endostatin and other variables were normally distributed. Most of the participants had a moderate level of physical activity with no gender related difference (p=0.370). The mean value for plasma endostatin in all samples was 105±12 ng/ml with range of 81–132 ng/ml. For males, it was 107±13 ng/ml, while for females; 102±12 ng/ml. There were no significant gender or ethnicity related differences in endostatin concentration. Moreover, endostatin was not significantly related with any anthropometric and physical variable. Conclusion: This study gives endostatin levels in normal healthy people and show no gender and ethnicity related differences in endostatin levels. Endostatin was not related with any anthropometric and physical variable

Empowerment of primary health care in an Outreach resource-limited district in Punjab: A strategy for improving adherence to Antiepileptic drug treatment in children with Epilepsy.

There is wide acknowledgement of the need for community involvement in the optimal management of children with epilepsy (CWE) in outreach financially constrained districts of the developing countries, but there is scarce data on comprehensive community-based childhood epilepsy treatment programs assessment

Insulin resistance, ethnicity and cardiovascular risk

Cardiovascular disease (CVD) is one of the leading causes of morbidity and mortality. The literature supports a series of established risk factors for CVD: age, gender, family history of CVD, ethnicity (un-modifiable); and high blood pressure, blood cholesterol, TGs, LDL, diabetes, pre-diabetes, obesity, smoking, physical inactivity, stress and unhealthy diet (modifiable). High blood pressure (hypertension) shares many of these risk factors. However, much of the variance/risk in both conditions cannot be explained. This has led to a search for novel risk factors, including insulin resistance and subclinical inflammation, the significance of which at present are controversial, particularly in relation to hypertension. There are also ethnic differences in the incidence, prevalence, risk factors and progression of cardiovascular disease. In some populations CVD occurs at an earlier age and progresses more rapidly. In this thesis I worked on two datasets in relation to hypertension, cardiovascular disease and their risk factors: (i) the RISC (Relationship between Insulin Sensitivity and Cardiovascular disease) study (chapters 2, 3, 5 and 6); and (ii) routinely-collected national data in Scotland via the SDRN (Scottish Diabetes Research Network) and SCI-Diabetes (chapter 2 and 7). Work on data from the RISC cohort focused on the relation between clamp-measured insulin sensitivity (its unique feature), inflammatory markers and hypertension; the SDRN work addressed ethnic differences in relation to diabetes and CVD. The first study (Chapter 3) examined the importance of insulin sensitivity/resistance in the development of hypertension and change in blood pressure over three years of follow-up in the healthy European (EU) RISC population. Systolic BP (SBP) was higher at baseline in insulin resistant (IR) women. There was no difference in BP in relation to IR in men. After adjustment for age, BMI, baseline BP and other covariates, low insulin sensitivity (M/I) predicted a longitudinal rise in SBP in women but not men, and SBP over time did not increase in insulin sensitive women. The second study (Chapter 4) was a systematic review of the relationships between two markers of low grade inflammation (IL-6 and CRP) and BP/hypertension, considering the roles of adiposity and insulin resistance. The systematic review showed evidence of considerable variation in the relationships amongst low grade inflammation, adiposity, insulin resistance and the development of hypertension. There appeared to be a positive association in the literature between CRP and DBP in younger individuals, although none of the studies were adjusted for insulin sensitivity determined by clamp technique. This association was further explored using RISC study data in Chapter 5 with stratification by sex and adjusting for clamp-derived insulin sensitivity. The third study (Chapter 5) examined the relationship of inflammatory markers with the development of hypertension and change in blood pressure over three years in the same healthy European population and whether any relationship was independent of clamp-measured insulin sensitivity (IS). High sensitivity C reactive protein (hsCRP) predicted prospective change in diastolic BP independent of insulin sensitivity and BMI whereas IL-6 had no relation with BP (both systolic and diastolic) or the incidence of hypertension. The fourth study (Chapter 6) evaluated all available predictors of BP rise over time (both systolic and diastolic) in a healthy EU population; moreover the significance of different predictors was examined within subgroups defined by age and sex. This analysis showed that baseline BP was the principal determinant of follow-up BP in all age and sex groups. Obesity was the second most important predictor (BMI in adults aged 30-44 years; percent change in BMI in middle age people aged 45-60 years). Lifestyle factors influenced BP via their effect on BMI. People who maintained their BMI during the three year follow-up did not exhibit a rise in BP (whether systolic or diastolic). Other important predictors identified in this analysis were insulin sensitivity in middle aged women and hsCRP in adult men. The fifth study (chapter 7) evaluated the role of ethnicity in the development of cardiovascular disease in people with type 2 diabetes living in Scotland. Over a follow-up of seven years, Pakistani people had increased risk of CVD and Chinese people had decreased risk of CVD as compared to White population. Pakistanis had an increased risk of CVD at a younger age independent of other conventional risk factors. In summary, insulin sensitivity and inflammation influence blood pressure, but their role is not generalised across different age and sex groups. BMI and change in BMI are important predictors of follow-up BP in adults and middle age healthy people, supporting a role for maintenance of BMI in preserving cardiovascular health. In addition to the known ethnic differences in the development of diabetes, I identified ethnic differences in the development of CVD