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Certification of a Multicomponent Reference Material from Natural Gas Mixture by Gravimetry and Dual GC-FID/TCD System

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Green and Sustainable Chemistry 2023年第4期13卷 269-290页

作者： Adel Bassuoni Shehata Abdulrahman rashed AlAskar Najjy Hamad AlYami Abdullah Suleiman AlOwaysi Chemistry Department National Measurement and Calibration Center (NMCC) Saudi Standards Metrology and Quality Organization (SASO) Riyadh Kingdom of Saudi Arabia

Natural gas (NG) is one of the most important sources of energy for industrial and domestic consumption in the present era because it is cheap and free from sulfur impurities. Therefore, accurate and precise measurement of its composition is of fundamental importance for trade reasons. To improve the quality of NG gas measurements, certified reference materials (CRMs) should be used for calibration of measuring equipment in order to ensure the traceability of the measurement results to the SI units. For the traceability purpose, a multicomponent natural gas mixture was prepared gravimetrically as a reference material according to ISO 6142 from pure helium, hydrogen, n-pentane, i-pentane, n-butane, i-butane, propane, ethane, hexane, methane and nitrogen. The preparation was done in two dilution steps in 5 L aluminum cylinders. The calculated mole fractions and associated uncertainties of natural gas components were verified by a dual GC-FID/TCD system in accordance with ISO 6143 calibrated by a series of primary gas mixtures (CRMs) produced by an NMI. The results obtained by gravimetry and by GC measurements have been checked for compatibility as required by ISO 6142 and were found in very good agreement. Details of the preparation and calculation of the mole fractions and uncertainties of all gas components are explained in this article.

关键词： Pure Gases Gravimetry Reference Material Stability GC Verification Uncertainty

Coal rib response during bench mining: A case study

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International Journal of Mining Science and Technology 2018年第1期28卷 107-113页

作者： Morgan M.Sears John Rusnak Mark Van Dyke Gamal rashed Khaled Mohamed Michael Sloan Ground Control Branch NIOSH Pittsburgh Mining Research Division

In 2016, room-and-pillar mining provided nearly 40% of underground coal production in the United *** the past decade, rib falls have resulted in 12 fatalities, representing 28% of the ground fall fatalities in *** coal *** of these 12 fatalities(75%) have occurred in room-andpillar *** objective of this research is to study the geomechanics of bench room-and-pillar mining and the associated response of high pillar ribs at overburden depths greater than 300 *** paper provides a definition of the bench technique, the pillar response due to loading, observational data for a case history, a calibrated numerical model of the observed rib response, and application of this calibrated model to a second site.

关键词： Deep cover Bench mining Thick seam Retreat mining Rib response Rib support

Analysis of Local Diagnostic Reference Levels for Pediatric Patients Undergoing 18F-FDG PET/CT Imaging for Oncology

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Journal of Applied Mathematics and Physics 2023年第7期11卷 2144-2155页

作者： Saad Alqahtani Khaled Soliman Saad Alotaibi Khaled Alnofaie Abdullah Alahmari Fahad Alyahya Abdullah Albdullah rashed Alharbi Radiodiagnostic and Medical Imaging Department Prince Sultan Military Medical City Riyadh Saudi Arabia Medical Physics Department Prince Sultan Military Medical City Riyadh Saudi Arabia

Background: The PET/CT imaging studies have two doses components the dose from the PET radiopharmaceutical and the other from the low dose CT used for PET images attenuation correction. We have one PET/CT scanner at our institution a Philips Time of Flight scanner. Our local patient’s radiation protection rules requires continuous assessment of radiation doses delivered to our patients. Purposes: The objectives of this study are to develop a weight- based facility DRLs for paediatric F-18-FDG PET-CT imaging for oncology in a large tertiary hospital and to determine whether the calculated DRLs compares with internationally published DRLs. Materials & Methods: Radiation dose data and patient demographics of two-hundreds and sixteen paediatric PET-CT oncology patients imaging procedures from one large tertiary hospital were selected and analysed in order to establish a facility paediatric DRLs. Statistical analysis was performed. Results: The PET dose reference levels ranged between [62 - 525] MBq of injected activity for a range of pediatric age groups. The CTDIvol values were between 3.5 and 16.5 mGy for all age groups. Comparison with current EANM and SNMMI recommendations of patient’s dose are discussed. Conclusion: Our pediatric PET/CT reference levels are higher than the ones reported internationally with notable variations. .

关键词： Diagnostic Reference Levels PET/CT 18-F-FDG Pediatric Radiation Dose CTDIvol Oncology

Safety and efficacy of posterior sub-Tenon＇s carboplatin injection versus intravitreal melphalan therapy in the management of retinoblastoma with secondary vitreous seeds

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International Journal of Ophthalmology(English edition) 2018年第3期11卷 445-455页

作者： Azza Mohamed Ahmed Said Mohamed Gamil Al Hazem Omar rashed Anwaar Mahmoud Rady Department of Ophthalmology Faculty of Medicine Ain Shams University Cairo 11566 Egypt Oncology and Radiation Medicine Department Faculty of Medicine Ain Shams University Cairo 11566 Egypt

AIM： To evaluate the safety and efficacy of posterior sub-Tenon＇s carboplatin injection compared to intravitreal melphalan injection in the management of retinoblastoma （RB） with secondary vitreous seeds. The outcome measures were vitreous seeds regression, need for other treatment modalities to achieve ocular salvage and treatment side effects. METHODS： A prospective interventional comparative nonrandomized study included RB eyes developed secondary vitreous seeds during the period of follow up. They subdivided into two groups： study group Ⅰ where posterior sub-Tenon＇s carboplatin （20 mg/2 mL） was injected and study group Ⅱ where intravitreal melphalan （20 μg/0.1 mL） was injected. The injections repeated every 2-4wk. RESULTS： Thirty-three eyes were included in the study. Seventeen eyes （16 patients） in study group Ⅰ and 16 eyes （16 patients） in study group Ⅱ. Ten eyes （30.3%） were completely salvaged following local chemotherapies, Ocular salvage was 23.5% following posterior sub-Tenon＇s carboplatin injection versus 37.5% following intravitreal melphalan raised to 47.1% and 75% with addition of external beam radiotherapy （EBR） with no statistically significant difference between the study groups （P=0.16）. A statistically significant correlation was found between ocular salvage rate and type of vitreous seeds either dust, spheres and clouds （r=0.42, P=-0.015） and eyes harbor new solid tumor growth （r=0.35, P=0.045）. The mean and median follow up periods following local chemotherapy injections were 2.0y in the study group Ⅰand 2.37y in the study group Ⅱ. Few complications were reported： periorbital edema in all eyes and ocular motility disturbances in 13 eyes （76.5%） following posterior sub-Tenon＇s carboplatin injection. Vitreous hemorrhage developed in 2 eyes （12.5%） and localized retinopathy in 5 eyes （31.25%） following intravitreal melphalan. ~ CONCLUSION： Local chemotherapy for treatment of RB with secondary vitreous seeds is safe and can salvage 30.3% of eyes

关键词： intravitreal melphalan posterior sub-Tenon'scarboplatin retinoblastoma secondary vitreous seeds

Effect of mesenchymal stem cells on anti-Thy1,1 induced kidney injury in albino rats

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Asian Pacific Journal of Tropical Biomedicine 2013年第3期3卷 174-181页

作者： Saber Sakr Laila rashed Waheba Zarouk Rania El-Shamy Department of Zoology Faculty of ScienceMenoufia University Department of Biochemistry Faculty of MedicineCairo University Center of Human Genetics and Human Genome Research National Research Center

Objective:To evaluate the effect of mesenchymal stem cells(MSCs)in rats with anti-Thy 1,***:Female albino rats were divided into three groups,control group,anti-Thy 1,1group and treatment with *** *** were derived from bone marrow of male albino rats,Y—chromosome gene was detected by polymerase chain reaction in the *** urea and creatinine were estimated for all *** of all studied groups was examined histologically and histochemically(total carbohydrates and total proteins).DNA fragmentation and expression ofα-SMA were ***:Kidney of animals injected with anti-Thy 1,1showed inflammatory leucocytic infiltration,hypertrophied glomeruli,tubular necrosis and congestion in the renal blood *** kidney tissue also showed reduction of carbohydrates and total proteins together with increase in apoptosis and in expression ofα-***,the levels of urea and creatinine were *** animals with MSCs revealed that kidney tissue displayed an improvement in the histological and histochemical *** andα-SMA expression were decreased,and the levels of urea and creatinine ***:The obtained results demonstrated the potential of MSCs to ameliorate the structure and function of the kidney in rats with anti-Thy 1,1 nephritis possibly through the release of paracrine growth factor(s).

关键词： Anti-Thy1,1 Nephritis Mesenchymal stem cells α-SMA Apoptosis

Artifact suppression and analysis of brain activities with electroencephalography signals

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Neural Regeneration Research 2013年第16期8卷 1500-1513页

作者： Md. rashed-Al-Mahfuz Md. Rabiul Islam Keikichi Hirose Md. Khademul Islam Molla Department of Computer Science and Engineering Pabna University of Science and Technology Department of Information and Communication Engineering The University of Tokyo Department of Computer Science and Engineering Rajshahi University

Brain-computer interface is a communication system that connects the brain with computer （or other devices） but is not dependent on the normal output of the brain （i.e., peripheral nerve and muscle）. Electro-oculogram is a dominant artifact which has a significant negative influence on further analysis of real electroencephalography data. This paper presented a data adaptive technique for artifact suppression and brain wave extraction from electroencephalography signals to detect regional brain activities. Empirical mode decomposition based adaptive thresholding approach was employed here to suppress the electro-oculogram artifact. Fractional Gaussian noise was used to determine the threshold level derived from the analysis data without any training. The purified electroencephalography signal was composed of the brain waves also called rhythmic components which represent the brain activities. The rhythmic components were extracted from each electroencephalography channel using adaptive wiener filter with the original scale. The regional brain activities were mapped on the basis of the spatial distribution of rhythmic components, and the results showed that different regions of the brain are activated in response to different stimuli. This research analyzed the activities of a single rhythmic component, alpha with respect to different motor imaginations. The experimental results showed that the proposed method is very efficient in artifact suppression and identifying individual motor imagery based on the activities of alpha component.

关键词： neural regeneration brain activity brain waves data adaptive filtering electroencephalography electro-oculogram artifact topographic mapping Wiener filtering neuroregeneration

A Secure Model for Preventing the Spread of COVID-19 in Bangladesh

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E-Health Telecommunication Systems and Networks 2022年第1期11卷 34-46页

作者： Shaznin Sultana Raisa Tahsin Taspia Md. Farhad Hossain Md. Nahiduzzaman Roksana Akter rashed Mazumder ICT Bangladesh University of Professionals Dhaka Bangladesh CSE Southeast University Dhaka Bangladesh IIT Jahangirnagar University Savar Union Bangladesh

An alarmingly high mortality and morbidity rate has been observed in COVID-19. As a new disease (similar group of SARS-CoV 2), it has been spread to more than two hundred countries and millions of people. However, COVID-19 infection is increasing in Bangladesh also. Therefore, an effective public health response is needed to control the outbreak of the mentioned new disease. If this high increasing factor turns out of control then it provides potential negative impact on social, economic, and political life of Bangladeshi people. One of the most effective ways to reduce or prevent the growth of COVID-19 is to wear masks. Many variants of COVID-19 are available in the world currently. Latest, there is a variant of omicron. This variant is too infectious. It means the vaccine seems to be not perfect against this deadliest disease COVID-19. However, people are not conscious enough about this matter generally. Nowadays, they are very reluctant to wear a mask. Their main thought is to get vaccinated and it can protect themselves. Definitely, the vaccine can protect at a certain level. However, Omicron proves that vaccine is not the ultimate solution. But, we can protect ourselves to wear a mask and keeping physical distance. This is the borderline of our research work. In this work, we proposed a system that will monitor the people who are outside the home/office via a close circuit camera. It evaluates whether the people are mask-free or not. If one does not wear a mask then an image will be captured and compared with database of national-data center for example NID server. As sensitive data, it needs security and protection. Hence, we adopt a cryptographic solution such as authenticated encryption or tag generation. As a result, receiver will be assured that a valid sender provides data to the valid receiver. The goal of this system proposal is to ensure wear face masks. As well, people will be punished based on the findings of mask-wearing. Furthermore, message authen

关键词： Face-Mask COVID-19 Awareness Public Health MAC Hash

市场环境下共享汽车电池仓库能量管理策略研究

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电测与仪表 2023年第2期60卷 53-59页

作者：林洋佳杨军 Ghamgeen Izat rashed 詹祥澎吴赋章龙雪梅武汉大学电气与自动化学院武汉430072

共享电动汽车是未来交通出行的发展趋势。将换电模式应用于共享电动汽车,在保持其换电便捷性优势的同时可以解决电池统一性的问题,具有良好的发展前景。文章对换电模式下共享电动汽车运营商管理的电池仓库开展研究,提出了能量优化管理... 详细信息

共享电动汽车是未来交通出行的发展趋势。将换电模式应用于共享电动汽车,在保持其换电便捷性优势的同时可以解决电池统一性的问题,具有良好的发展前景。文章对换电模式下共享电动汽车运营商管理的电池仓库开展研究,提出了能量优化管理的双层规划模型。上层以电池仓库成本最小化为目标对电池充放电功率进行优化,下层对电池仓库参与电力市场的出清过程进行建模,然后基于KKT条件和强对偶理论将模型转换成混合整数线性规划问题进行求解。通过算例分析电池仓库的竞价和能量管理策略,验证了文中所提模型可以在满足共享用户电池需求的同时,降低共享汽车电池仓库的运营成本。

关键词：共享电动汽车电池仓库换电双层规划

Forcing ocean model with atmospheric model outputs to simulate storm surge in the Bangladesh coast

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Tropical Cyclone Research and Review 2020年第2期9卷 117-134页

作者： Nabir Mamnun Lucy M.Bricheno Md rashed-Un-Nabi Nansen-Bangladesh International Centre for Coastal Ocean and Climate StudiesHouse 10Road 16AGulshanDhaka1212Bangladesh Faculty of Marine Sciences and Fisheries University of ChittagongChattagram4331Bangladesh National Oceanography Centre Joseph Proudman BuildingBuilding6 Brownlow StreetLiverpoolL35DAUK

Tropical cyclones are devastating hazards and have been a major problem for the coastal population of B *** the advancements in atmospheric and oceanic prediction,accurate forecasting of storm surges is of specific interest due to their great potential to inflict loss of life and *** decades,the numerical model based storm surge prediction systems have been an important tool to reduce the loss of human lives and property *** order to improve the accuracy in predicting storm surge and coastal inundation,recent model development efforts tended to include more modeling components,such as meteorology model and surface wave model in storm surge *** this study,we used the outputs of an atmospheric model to force the ocean model for simulating storm surges in the Bay of Bengal with particular focus on the Bangladesh *** ability of the modeling system was investigated simulating water levels in the Bangladesh coast of two tropical cyclones Sidr(2007)and Aila(2009).The effectiveness of the model was verified through comparing the obtained computational outputs against tide gauge *** cyclone tracks and intensities reproduced by the atmospheric model were reasonable,though the model had a tendency to overestimate the cyclone intensity during peaks and also close to *** water levels are reproduced fairly well by the ocean model,although errors still *** root mean square errors in water level at different gauges range from 0.277 to 0.419 m with coefficient of correlation(R^2)between 0.64 and 0.97 in case of Sidr and0.209-0.581 m with R^20.62 to 0.98 for *** overall coupled modeling system is found to be useful with reasonable accuracy and precision,though there are spaces for ***-resolution modeling approaches are recommended to gain more skills.

关键词： Tropical cyclone Storm surge One-way coupling Bay of bengal