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This paper proposes a technique for synthesizing multiple point target scatterer Synthetic Aperture Radar (SAR) echoesin real-time. Traditional approaches require high computation resources to calculate the complex SAR echoes due to its complex mathematical model. The proposed technique employs the low computation Direct Digital Synthesis (DDS) approach to generate these complex sinusoid echoes. The proposed Synthetic Aperture Radar Echoes Synthesizer(SAR-ES)is capable of synthesizing SAR echoes accurately in real-time and was built in a Field Programmable Gate Array (FPGA) platform. The system can be used as a testbed to validate and evaluate the performance of a real-time SAR processing algorithms/system prior to the actual flight mission. This could help in reducing the frequency of flight trials and to reduce the SAR system development risk especially for satellite-borne SAR system.

Context Transgender youth may initiate GnRH agonists (GnRHa) to suppress puberty, a critical period for bone-mass accrual. Low bone mineral density (BMD) has been reported in late-pubertal transgender girls before gender-affirming therapy, but little is known about BMD in early-pubertal transgender youth. Objective To describe BMD in early-pubertal transgender youth. Design Cross-sectional analysis of the prospective, observational, longitudinal Trans Youth Care Study cohort. Setting Four multidisciplinary academic pediatric gender centers in the United States. Participants Early-pubertal transgender youth initiating GnRHa. Main Outcome Measures Areal and volumetric BMD Z-scores. Results Designated males at birth (DMAB) had below-average BMD Z-scores when compared with male reference standards, and designated females at birth (DFAB) had below-average BMD Z-scores when compared with female reference standards except at hip sites. At least 1 BMD Z-score was Conclusions In early-pubertal transgender youth, BMD was lower than reference standards for sex designated at birth. This lower BMD may be explained, in part, by suboptimal calcium intake and decreased physical activity–potential targets for intervention. Our results suggest a potential need for assessment of BMD in prepubertal gender-diverse youth and continued monitoring of BMD throughout the pubertal period of gender-affirming therapy.

Background Minimizing scarring has long been a challenge in plastic surgery. Factors affecting scar formation are well known, but the effect of some patient-specific factors such as dermal thickness remains unverified. Management of factors predictive of scarring can improve postoperative patient satisfaction and scar treatment. Methods For 3 years, we used ultrasonography to measure dermal thickness in female patients who had undergone thyroidectomy for cancer at our hospital. We confirmed the influence of dermal thickness on hypertrophic scar formation and the Patient and Observer Scar Assessment Scale scar score 6 months after surgery. Results There was a positive correlation between dermal thickness and scar score (pl0.05), and dermal thickness appears to be a cause of hypertrophic scar formation (pl0.05). Conclusion Thick dermis was found to cause poor scar formation and hypertrophic scarring. Prediction of factors that can influence scar formation can be used to educate patients before surgery and can help in scar management and improvement in patient satisfaction.

Objective The use of different expressions between physicians frequently results in confusion in the process of diagnosis and treatment of patients with headaches due to problems in the nose and nasal cavity. The aim of this study was to assess the terminologies that have been used most frequently to standardize these terminologies. Methods Terminologies that are most frequently used in general, including rhinogenic migraine, sinus headache, rhinogenic contact point headache, middle turbinate headache syndrome, and rhinogenic headache, were found by searching PubMed, Web of Science, and Google Scholar. These terminologies were objectively assessed on the basis of existing research and definitions and the range of diagnoses by organizations with public credibility. Results There were many terminologies in use for headache related to nose; however, these were not logical expressions and only partly explained the phenomenon. Among the terms, "rhinogenic headache" was most appropriate in expressing and describing the related symptoms. Conclusion The results indicated that the term "rhinogenic headache" is most appropriate for describing pain in the nose and eyes in patients with deformation within the nose or the nasal cavity due to external injuries or underlying diseases related to nose as observed on computed tomography.

Attendance process in a university’s event is time consuming and tracking the attendance can be harder. In this paper, a smart event attendance system for a university using QR code and GPS technology is proposed with objective to speed up the process of taking students’ attendance and tracking full attendance. The method of developing the system is based on two views; user view which is the mobile application used by the students, and admin view which is the web administration system used by the event organizer. From the evaluation, students’ attendance can be traced from the GPS location combine with QR code. The results indicate that full attendance increases as the system validates attendance through users’ identification, location and timestamp during user login and logout. The proposed system contributes to high satisfaction among the users that claim that the mobile application helps to speed up the event registration process.

Despite decades of scientists' effort, absolute phase determination of interferometry synthetic aperture radar (InSAR) image still remains unsolved. InSAR measurement derived from phase data is not only ambiguous by its modulo-2pi mathematical-ill pose, but also further corrupted by noise. Therefore, we suggest an adaptive least mean square (LMS) algorithm based on steepest descent method for noise reduction purpose. Besides, a scheme which incorporates such filter into a Itoh two-dimensional phase-unwrapping is proposed. The phase estimation procedures are implemented to reconstruct a simulated interferogram of terrain structure. For the quantitative assessment, we employ different types of quality metrics to measure the estimated outcome of InSAR terrain image which includes root mean square error (RMSE) and signal-to-noise ratio (SNR). The estimated outcomes are also reconstructed into three dimensional plotting for visual assessment. By refering to the similar scheme, other noise reduction filters include wieners filter and median filter are implemented for performance comparison. The simulated results show that the proposed method is able to filter noise without corrupted the useful phase information and achieves lowest error energy among other filters. Thus, it is a valuable technique for InSAR terrain phase estimation.

Scanning transmission ion microscopy (STIM) is a technique which utilizes the energy loss of high energy (MeV) ions passing through a sample to provide structural images. In this paper, we have successfully demonstrated STIM imaging of single cells at the nano-level using the high resolution capability of the proton beam writing facility at the Centre for Ion Beam Applications, National University of Singapore. MCF-7 breast cancer cells (American Type Culture Collection [ATCC]) were seeded on to silicon nitride windows, backed by a Hamamatsu pin diode acting as a particle detector. A reasonable contrast was obtained using 1 MeV protons and excellent contrast obtained using 1 MeV alpha particles. In a further experiment, nano-STIM was also demonstrated using cells seeded on to the pin diode directly, and high quality nano-STIM images showing the nucleus and multiple nucleoli were extracted before the detector was significantly damaged.

Contactor pin is commonly used as the test tooling to enable million times of repeatability functional testing in manufacturing. Simulation should be performed before contactor sent for prototyping. The objective is to optimize the design according to device performance and avoid design faulty which may lead to higher testing cost. This paper introduces the methodology on contactor pin characterization specifically the pin inductance that are helpful for high speed tooling engineer to access their contactor's performances. The impact of the contactor pin design, topology and contactor housing design will be explained in this paper. Indirectly, this is to emphasize the importance of assessing the contactor by considering many design factors instead of assessing in ideal way. It is widely applicable to any electronic devices testing that need contactor.

Lane detection plays an important role in intelligent vehicle systems. Therefore, this paper presents a robust road lane marker detection algorithm to detect the left and right lane markers. The algorithm consists of optimization of Canny edge detection and Hough Transform. The system captures images from a front viewing vision sensor placed facing the road behind the windscreen as input. Then a series of image processing is applied to generate the road model. Canny edge detection performs features recognition then followed by Hough Transform lane generation. The algorithm detects visible left and right lane markers on the road based on real-time video processing.

Background Like their counterparts in many other nations, physicians in Singapore are tasked with providing care, conducting research, and teaching and providing leadership to junior doctors. In this paper, we describe our experience implementing the first chief residency program in Singapore. Initiative A pilot of a chief residency program was initiated in the Department of Medicine at National University Hospital in July 2008, with 1 chief resident (CR) and 2 associate CR positions. The pilot used the US model for CR training as the initial framework. CRs would assist in the orientation and integration of new residents, teach residents, promote camaraderie among residents, help resolve issues, function as a liaison to senior staff, and would be developed as potential health care leaders and physician role models. Results The CRs performed a host of administrative duties and initiated several improvements in the residency, including better practices for leave scheduling, call roster planning, and a night float system. CRs attended monthly meetings with division heads and participated in departmental strategic planning as well as professional development and leadership courses. The CR position was well regarded by the other residents, and this resulted in increased interest in identifying and addressing opportunities for improvement. The introduction of a chief residency also made the department a more attractive posting for residents and contributed to a significant increase in the number of applicants for residency rotations. Conclusions A chief residency program can benefit residents' morale and a CR's development as a leader, and it can facilitate linkage between junior and senior hospital management that promotes active involvement in problem solving and clinical and education improvement. Support from hospital administrators and senior clinicians is essential, and mentoring and succession planning are important to ensure the program's continued success.

This paper is describing a methodology of improvement project that is carried out in a company that supplies electronic communication plastic parts. By using the lean tools, the focus of the paper is to improve the manual assembly line by adopting lean tool for the process improvement. The process improvement are divided into several phases, from defining the goal until the test run of the solution, with different lean concept being used at different phase. The improvement had been done phase by phase in order to ensure the impact of the improvement. Through the test run, the proposed solution based on concept of Lean production increase profitability based on idling time reduction (81.64%) and operator saving(40%) in operation.

A novel dual band antenna for Wireless Local Area Network (WLAN) applications is presented. The dual band characteristic is achieved by feeding two different length resonant paths with a 50 Ω microstrip line. The compact antenna only occupies 5.3 × 16 mm2 and promotes wideband characteristic. The bandwidth for lower resonance spans from 2.03 GHz to 2.80 GHz (30.3%) and 4.86 GHz to 6.44 GHz (31.6%) at higher band, effectively fulfilling the bandwidth requirement of IEEE 802.11b/g and IEEE 802.11a. The return loss, gain and radiation patterns of the proposed dual band antenna are depicted in this paper. Gain of 6.15 dB and 2.12 dB is obtained at lower resonant frequency 2.44 GHz and higher resonant frequency 5.21 GHz, respectively.

Analyses the strategic marketing practices of the six major banking groups in Hong Kong. Details significant differences. Attributes these to the regulatory constraint which confines banks coming late to the wholesaling business. Wider application of marketing is still limited to the well‐established banks with a large retailing customer base. Hong Kong banking is generally perceived as a favourable location for exploring Asian businesses. Suggests that, in order to strengthen further the status of Hong Kong as an international financial and banking centre, a stable political environment and effective cost control programme are indispensable.

An unmanned reconnaissance aerial vehicle mounted sensor of footprint with a small area /spl omega//sub s//sup 2/ is used to cover critical airbase structures for damage assessment. The region of coverage interest is modeled with a closed union of a minimal set of interior disjoint rectangles of width /spl omega//sub i/ = /spl omega//sub s/. We wish to find a minimum-length flight path for complete coverage for the nonholonomic vehicle. We prove that our minimization problem is a traveling salesman problem (TSP) that is symmetric, non-Euclidean and satisfies the triangular inequality. We compare our modeling primitive with two simple primitives commonly used for representing coverage regions. An ant colony optimization heuristic for solving the TSP is presented.