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

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

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

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

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

Training / Irrigation / Evaluation / Malaysia

Esports Analytics on PlayerUnknown's Battlegrounds Player Placement Prediction using Machine Learning

PUBG (PlayerUnknown’s Battlegrounds) is a video game that has become popular in the past year. This paper aims to predict the placement of PUBG players during the match by detecting the influential features set that can impact the outcome of the PUBG game and build the best prediction model using a machine learning approach. In this study, the dataset is taken from Kaggle, which has 29 attributes that are categorized into one label (winPlacePerc). The training set has divided into five sets with each set has 6000 instances. The decision tree regression model was applied to find the optimum prediction. Other regression models such as Linear Regression and Support Vector Machine are also utilized to compare with the decision tree model’s result. Based on the result analysis, the walkDistance feature was deemed as the most significant factor influencing the results of a PUBG game. Furthermore, there are other common features obtained from the five datasets that represent the crucial factors which are boosts, DBNOs, killPlace, kills, rideDistance and matchDuration. From the three regression models, the Support Vector Machine model built on the significant features has the best performance in terms of RMSE value while the Decision Tree Regression model has the fastest prediction speed among these regression models

Personalising Head and Neck Cancer Survivorship: Intervention with the Head and Neck Cancer Patients Concerns Inventory in Routine Head and Neck Cancer Outpatient Visits

The Head and Neck Patients Concerns Inventory (HN-PCI) is a self-completed holistic tool that helps patients to disclose items of concern they wish to discuss. The MD study was designed to evaluate the roll-out of HN-PCI in subjects who were unfamiliar with it. The primary aim of the study was to evaluate HN-PCI can help patients self-disclose concerns. The secondary aims were to: (1) categorise HN-PCI items into domains; (2) develop a thematic content analysis; (5) examine associations between concerns and distress; (4) examine associations between clinicopathological factors with HN-PCI consultations; (5) determine if HN-PCI intervention changes consultations and the outcomes of consultations. Method: The MD work was divided into 3 sections and undertaken in the following order: (1) Pilot study; (2) Domain generation; and (3) Main study. Sections (1) and (2) were undertaken designed to support the Main study. In the Main study, patients were recruited prospectively to a non-randomised study design composed of 3 blocks. Block 1 constituted normal practice i.e. control group, Block 2 constituted patients exposed to HN-PCI but doctors were not i.e. control in attention, and Block 3 was the HN-PCI intervention group. The primary outcome measures were the number of concern and selected and/or discussed. The secondary outcome measures were patient satisfaction with consultation, consultation length, distress level and clinical outputs. i.e. clinical decision or action taken related to the consultation. Result: In the Pilot study, a content thematic framework was developed. Five domains were generated: (A) Physical and functional; (B) Psychological/emotional and spiritual well-being; (C) Social care/Social well-being; (D) Treatment-related; and (E) Other. In the Main study, 365 patients were recruited, producing a matching number of audiorecorded consultation i.e. Block 1: 136 patients; Block 2: 78 patients; and Block 3: 111 patients. Introduction of HN-PCI generated a trend towards an increased number of concerns discussed when compared with control consultations. A broader range of expressed concerns was addressed in HN-PCI intervention group. More items within the Psychological/emotional and Spiritual well-being Domain were discussed in HN-PCI intervention groups. In the HN-PCI intervention groups, doctors were fair to moderately more likely to take on the patient’s agenda for discussion by addressing the items selected. These were achieved with a trend towards longer consultations. Consultations with HN-PCI were significantly associated with certain clinicopathological factors. The HN-PCI intervention group showed higher number of medical outputs when compared with control group, suggesting that HN-PCI may facilitate collaborative decision-making. Patients with HN-PCI intervention showed a trend towards lower levels of distress post-consultation and reported significantly higher scores of satisfaction. This study also demonstrated that the HN-PCI was able to indirectly predict patients who experienced significant distress based on the number of items selected. Conclusions HN-PCI was able to help patients disclose a wider range of concerns in cohorts unfamiliar with the tool. Its use is associated with changes in the content of consultations, suggesting a more patient-concern focused consultation. This is possible to create a personalised, patient-centred HNV visit using the HN-PCI. However, there remain service-based barriers to fully realizing the HN-PCI tool in personalising HNC patient’s survivorship trajectory

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

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