16 research outputs found

    Tensile behaviour for mercerization of single kenaf fiber

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    A natural fiber including kenaf fibers that reinforce with polymeric composite has increased attention in the manufacturing industries. However, the poor adhesion between fiber and matrix are commonly encountered respectively to their compatibility nature namely hydrophilic and hydrophobic. Therefore, alkaline treatment has introduced to reduce the hydrophilic effect of natural fiber. This paper presents the treatment of single kenaf fibers following tensile test and predicted using analysis of variance (ANOVA). Here, the kenaf fibers were modified using NaOH at different solutions. Then, the single kenaf fiber was performed under ASTM D3379-89 standard. The results showed that kenaf fiber which treats with NaOH solution of 6% significantly offered the outstanding performance of the tensile behaviour

    Delayed presentation of traumatic diaphragmatic hernia: a case report

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    Traumatic diaphragmatic hernias are an unusual presentation of trauma. The diagnosis is often missed because of non-specific clinical signs, and the absence of additional intra-abdominal and thoracic injuries. Thus, a delay in diagnosis may occur which, in the presence of obstruction and/or strangulation, is associated with a high mortality and morbidity

    Chemical treatment evaluation of tensile properties for single kenaf fiber

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    The attractions to kenaf fiber as reinforcement in polymer composite are getting wider. However, the hydrophilic in nature is one of the affecting factors to their properties. Treatment to the fiber using sodium hydroxide (NaOH) has significantly proven to improve the drawback. This paper presents the mechanical properties of untreated and treated of single. Initially, kenaf fibers were treated with sodium hydroxide with varies of concentration, soaking time and drying period of conditions. Then, each of kenaf fibers is mounted on a cardboard paper frame. The single fiber tests are performed in accordance with ASTM D3379-89. Prior to testing, the frame sides were carefully cut in the middle. It has been shown that treated fibers with 6% of NaOH significantly offered an outstanding performance than the untreated

    Speed sensorless control for PMSM drives using Extended Kalman Filter

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    In this paper, Sensorless Permanent Magnet Synchronous Motor (PMSM) using Extended Kalman Filter (EKF) is presented. The previous PMSM drive uses a sensor to measure the motor’s speed. Then the idea is to replace the sensor by using sensorless drives based on the observer. For the conventional observer, it’s only good for low current and low-speed applications. Moreover, it is hard to detect the phase voltage due to the non-existence of neutral wire. Therefore, this project proposes sensorless control using an EKF. This method provides an optional estimation algorithm for the non-linear system that can produce a fast and accurate estimation of state variables. The accurate estimation will reduce the noise and ripple of the system. Additionally, the EKF do not require the information of mechanical parameters and the initial position of the rotor, making the construction is easy and simple. In this paper, the fundamental of the EKF algorithm is explained and the simulation results for different speeds and loads are presented. The noise reduction test is also conducted to measure the flux current with and without the filter. The simulation study is achieved using MATLAB/Simulink to verify the effectiveness of the proposed method. The results of the simulation show that the sensorless PMSM drives using EKF have lower overshoot and faster rise time during start-up conditions and have lower undershoot during the loaded condition. It also can be concluded that the proposed sensorless PMSM drive using EKF has good speed control accuracy and can reduce the current noise

    Connecting Library with APEX Community

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    Hamzah Sendut Library as an APEX university library has taken a more proactive approach to rebrand promotional and outreach programs. A more creative, unique and inno-vative style have been used to ensure that the library's mis-sion in reaching out to the users is accomplished. ‘Skuad Pelanggan’ was formed to increase the effectiveness of library’s engagement with customers. The ultimate goal is to reach out to customers, increase the usage of library facilities, improving the relevance of the existence of the library in the campus community and provide additional value to the library users. Important aspects emphasized in the program include teaching and learning supports, with the focus on research and consultation. Efforts conducted through myPHS programs, exhibitions, and virtual market-ing have established positive impacts and realization of library’s relevance by the campus community

    Infected pancreatic necrosis: outcomes and clinical predictors of mortality. A post hoc analysis of the MANCTRA-1 international study

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    : The identification of high-risk patients in the early stages of infected pancreatic necrosis (IPN) is critical, because it could help the clinicians to adopt more effective management strategies. We conducted a post hoc analysis of the MANCTRA-1 international study to assess the association between clinical risk factors and mortality among adult patients with IPN. Univariable and multivariable logistic regression models were used to identify prognostic factors of mortality. We identified 247 consecutive patients with IPN hospitalised between January 2019 and December 2020. History of uncontrolled arterial hypertension (p = 0.032; 95% CI 1.135-15.882; aOR 4.245), qSOFA (p = 0.005; 95% CI 1.359-5.879; aOR 2.828), renal failure (p = 0.022; 95% CI 1.138-5.442; aOR 2.489), and haemodynamic failure (p = 0.018; 95% CI 1.184-5.978; aOR 2.661), were identified as independent predictors of mortality in IPN patients. Cholangitis (p = 0.003; 95% CI 1.598-9.930; aOR 3.983), abdominal compartment syndrome (p = 0.032; 95% CI 1.090-6.967; aOR 2.735), and gastrointestinal/intra-abdominal bleeding (p = 0.009; 95% CI 1.286-5.712; aOR 2.710) were independently associated with the risk of mortality. Upfront open surgical necrosectomy was strongly associated with the risk of mortality (p < 0.001; 95% CI 1.912-7.442; aOR 3.772), whereas endoscopic drainage of pancreatic necrosis (p = 0.018; 95% CI 0.138-0.834; aOR 0.339) and enteral nutrition (p = 0.003; 95% CI 0.143-0.716; aOR 0.320) were found as protective factors. Organ failure, acute cholangitis, and upfront open surgical necrosectomy were the most significant predictors of mortality. Our study confirmed that, even in a subgroup of particularly ill patients such as those with IPN, upfront open surgery should be avoided as much as possible. Study protocol registered in ClinicalTrials.Gov (I.D. Number NCT04747990)

    Global disparities in surgeons’ workloads, academic engagement and rest periods: the on-calL shIft fOr geNEral SurgeonS (LIONESS) study

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    : The workload of general surgeons is multifaceted, encompassing not only surgical procedures but also a myriad of other responsibilities. From April to May 2023, we conducted a CHERRIES-compliant internet-based survey analyzing clinical practice, academic engagement, and post-on-call rest. The questionnaire featured six sections with 35 questions. Statistical analysis used Chi-square tests, ANOVA, and logistic regression (SPSS® v. 28). The survey received a total of 1.046 responses (65.4%). Over 78.0% of responders came from Europe, 65.1% came from a general surgery unit; 92.8% of European and 87.5% of North American respondents were involved in research, compared to 71.7% in Africa. Europe led in publishing research studies (6.6 ± 8.6 yearly). Teaching involvement was high in North America (100%) and Africa (91.7%). Surgeons reported an average of 6.7 ± 4.9 on-call shifts per month, with European and North American surgeons experiencing 6.5 ± 4.9 and 7.8 ± 4.1 on-calls monthly, respectively. African surgeons had the highest on-call frequency (8.7 ± 6.1). Post-on-call, only 35.1% of respondents received a day off. Europeans were most likely (40%) to have a day off, while African surgeons were least likely (6.7%). On the adjusted multivariable analysis HDI (Human Development Index) (aOR 1.993) hospital capacity > 400 beds (aOR 2.423), working in a specialty surgery unit (aOR 2.087), and making the on-call in-house (aOR 5.446), significantly predicted the likelihood of having a day off after an on-call shift. Our study revealed critical insights into the disparities in workload, access to research, and professional opportunities for surgeons across different continents, underscored by the HDI

    Tensile properties analysis and characterization of single fiber and biocomposites

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    The natural fiber is an emerging area in polymer science and the best option for replacing synthetic polymer in relevant applications. The study reviewed the future development of tensile strength and stiffness properties of monotonic single fiber and biocomposite using Weibull analysis. The Weibull distribution model that statistically interprets the reliability of distribution of tensile test was deeply discussed. The distinctive parameters, especially in determining the Weibull modulus (m), were also examined. Further, the latest trend in evaluating the single fiber and biocomposite structures by using a statistical approach was addressed
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