Quadrature Phase Shift Keying (QPSK) Modulator Design using Multi-Port Network in Multilayer Microstrip-Slot Technology for Wireless Communication Applications

The design of the quadrature phase shift keying (QPSK) modulator by using a multi-port network is proposed in this article for the use in wireless communication applications. The multi-port network is in the form of multilayer microstrip-slot technology. This multi-port network is composed of three 3-dB rectangular-shaped directional couplers with virtual stubs and an equal power division divider with in-phase characteristic. The design is performed by applying a full-wave electromagnetic simulation software, CST Microwave Studio (CST MWS). Keysight’s Advanced Design System (ADS) is applied in analyzing and evaluating the QPSK constellation of the proposed modulator. This comparatively small size of proposed design has been fabricated, and its wideband performance of 2 to 6 GHz is verified

Automated characterization of single-photon avalanche photodiode

We report an automated characterization of a single-photon detector based on commercial silicon avalanche photodiode (PerkinElmer C30902SH). The photodiode is characterized by I-V curves at different illumination levels (darkness, 10 pW and 10 uW), dark count rate and photon detection efficiency at different bias voltages. The automated characterization routine is implemented in C++ running on a Linux computer.Comment: Have permission to post journal-formatted version on arXi

Performance of a multi-stack microchannel heat sink

The usage of a very large scale integrated circuits generate high heat fluxes and require an effective cooling system. A microchannel heat sink (MCHS) is one of the reliable cooling systems that had been applied. In terms of performance, a MCHS can be appraised by obtaining low total thermal resistance and pumping power. However, as the total thermal resistance decreases, the pumping power will increase. A few studies have been focused on the minimization of the thermal resistance and pumping power of a multi-stack MCHS. Optimization of two objective functions which are the total thermal resistance and pumping power has been done by using genetic algorithm. It is demonstrated that both objective functions can be minimized by optimizing two design variables which are the channel aspect ratio, α, and wall width ratio,β. It was found that the usage of a stacked configuration for the MCHS is able to reduce the total thermal resistance. From the optimization, it was found that the optimum number of stacks that can be implemented is three. With the three-stack configuration, the total thermal resistance found is 0.1180 K/W which is 21.8% less compared to the single-stack MCHS. However, the pumping power needed for the three-stack MCHS is increased by 0.17 % compared to single-stack which is 0.7535 W

How head and neck consultants manage patients’ emotional distress during cancer follow-up consultations : a multilevel study

Head and neck cancer (HNC) patients suffer substantial emotional problems. This study aimed to explore how utterance-level variables (source, type and timing of emotional cues) and patient-level variables (e.g. age, gender and emotional well-being) relate to consultants’ responses (i.e. reducing or providing space) to patient expressions of emotional distress. Forty-three HNC outpatient follow-up consultations were audio recorded and coded, for patients’ expressions of emotional distress and consultants’ responses, using the Verona Coding Definitions of Emotional Sequence. Multilevel logistic regression modelled the probability of the occurrence of consultant reduce space response as a function of patient distress cue expression, controlling for consultation and patient-related variables. An average of 3.5 cues/concerns (range 1–20) was identified per consultation where 84 out of 152 total cues/concerns were responded by reducing space. Cue type did not impact on response; likewise for the quality of patient emotional well-being. However, consultants were more likely to reduce space to cues elicited by patients, as opposed to those initiated by themselves. This reduced space response was more pronounced as the consultation continued. However, about 6 min into the consultation, this effect (i.e. tendency to block patients) started to weaken. Head and neck consultants’ responses to negative emotions depended on source and timing of patient emotional expressions. The findings are useful for training programme development to encourage consultants to be more flexible and open in the early stages of the consultation.PostprintPeer reviewe

Numerical simulation of flow surrounding a thermoacoustic stack:single-stack against double-stack plate domain

Over the last few decades, numerical simulation has fast become an effective research tool in analyzing internal and external fluid flow. Much of the unknowns associated with microscopic bounded and unbounded fluid behavior generally not obtainable via experimental approach can now be explained in details with computational fluid dynamics modeling. This has much assist designers and engineers in developing better engineering designs. However, the choice of the computational domain selected plays an important role in exhibiting the correct flow patterns associated with changes in certain parameters. This research looked at the outcomes when two computational domains were chosen to represent a system of parallel stack plates in a thermoacoustic resonator. Since the stack region is considered the “heart” of the system, accurate modeling is crucial in understanding the complex thermoacoustic solid-fluid interactions that occur. Results showed that although the general flow pattern and trends have been produced with the single and double plate stack system, details of a neighboring solid wall do affect the developments of vortices in the stack region. The symmetric assumption in the computational domain may result in the absence of details that could generate an incomplete explanation of the patterns observed such as shown in this study. This is significant in understanding the solid-fluid interactions that is thermoacoustic phenomena

Marine Sourced Glycosaminoglycans ‘GAGs'

Globally, there is an uprising interest for availability of tangible, novel, added value, sustainable commercial exploitable therapeutic compounds from naturally derived sources. The paper will highlight bioactive compounds of therapeutic potential from marine sources such as polysaccharides, especially glycosaminoglycans. It is now well documented, and this effort combined with a green technological approach in sustainable natural biodiversity will allow the development of a new generation of therapeutics. Outsourcing for a biocompatible, non-mutational bioactive compound such as GAG's in a worldwide research and industrial agenda. Hence, the thorough understanding on how the biosynthesis, structure and function of complex glycosaminoglycans will reveal the polysaccharides from the marine environment could provide a valid alternative to traditional polysaccharides such as glycosaminoglycans

Training needs assessment in Malaysia: Exercise held at Kuala Lampur and Kota Bharu from 13th October 1989

Training / Irrigation / Evaluation / Malaysia

Hubungan Belajar Mandiri dengan Prestasi Belajar Pai di Mtsn 1 Konawe Selatan

Tujuan penelitian kausal ini adalah untuk mendapatkan informasi mengenai pengaruh gaya kepemimpinan, kompetensi profesional, kompetensi pedagogik, dan iklim kerja terhadap prestasi kerja guru bahasa inggris SMP Kota Kendari. Penelitian dilakukan dengan menggunakan metode survei dan pengujian hipotesis menggunakan analisis jalur. Sampel penelitian guru bahasa Inggris SMP sebanyak 80 orang. Hasil penelitian adalah sebagai berikut (1) Ada pengaruh positif langsung gaya kepemimpinan terhadap prestasi kerja; (2) Ada pengaruh positif langsung kompetensi profesional terhadap prestasi kerja; (3) Tidak ada pengaruh positif langsung kompetensi pedagogik terhadap prestasi kerja; (4) Ada dampak positif langsung iklim kerja terhadap prestasi kerja; (5) Ada pengaruh positif langsung gaya kepemimpinan terhadap iklim kerja; (6) Ada pengaruh positif langsung kompetensi profesional terhadap iklim kerja; (7) Ada pengaruh langsung langsung kompetensi pedagogik terhadap iklim kerja. Berdasarkan temuan tersebut, dapat disimpulkan bahwa prestasi kerja guru bahasa Inggris SMP di Kota Kendari dapat ditingkatkan dengan meningkatkan gaya kepemimpinan, kompetensi profesional, kompetensi pedagogik dan iklim kerja

Using the Patients Concerns Inventory for Distress Screening in Post-treatment Head and Neck Cancer Survivors, Journal of Cranio-Maxillofacial Surgery in press.

Purpose Cancer patients can experience significant distress during their cancer trajectory, which impacts upon clinical outcomes and quality of life. Screening for distress using holistic assessments can help identify and address unmet concerns/needs. The purpose of this study was to evaluate the relationship between concerns and distress, and the impact of distress on clinic outcomes in post-treatment head and neck cancer patients. Methods 170 patients attending routine follow-up clinics were prospectively recruited. All patients completed the Patient Concerns Inventory (PCI) and the Distress thermometer (DT) at preconsultation. Results The rate of significant distress (i.e. DT cut-off score ≥4) was 36% (62/170). Significantly distressed patients selected more items overall than patients without distress (mean, median (QR) of 5.40, 5 (2–8) vs 2.61, 2 (0–4), p < 0.001). Significant distress was most strongly associated with Physical and Functional well-being (p < 0.001) and Psychological and Emotional well-being domains (p = 0.001). On balance, very little difference was noted between cut-off points of either ≥4 or ≥5 PCI items of concern selected. Both cut-off points demonstrated an acceptable level of sensitivity, specificity and predictive values for significant distress. Consultations were longer with increasing numbers of concerns. Conclusions Just over one-third of patients are significantly distressed. They were more likely to express a higher number of concerns. A cutoff score ≥4 or ≥5 PCI items selected can identify those at risk of significant distress. Concerns causing significant distress were related to emotional/psychological issues and physical function