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A Study of Ch.mical, Mineral Compositions (of Some Metals) and Natural Radioactivity in Porcelain and Ceramic Dinner Ware

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Journal of Geoscience and Environment Protection 2020年第11期8卷 209-221页

作者： safia h. q. hamidalddin Ph.sics Department Faculty of Science Jeddah University Jeddah Saudi Arabia

Fifteen Porcelain and Ceramic Dinner Wares samples (collected from local commercial suppliers—Jeddah.Saudi Arabia) were studied applying X-Ray Diffraction and Atomic Absorption tech.iq.es were used to study th. Ch.mical, Mineral, Compositions Concentrations (of Some Metals). In addition, th. Natural Radioactivity measurements of 226Ra, 232Th.and 40K, was used by a h.gh.purity germanium (h.Ge) detector. X-ray diffraction results sh.wed th.t th. major mineral constituents of 15 samples were q.artz (SiO2) (except one), minor and trace elements vary from sample to sample. Atomic absorption spectroscopy results of th. concentrations for (Al, Pb, Bi, U, Th.and K) in (ppm) sh.wed th.t Al2O average was 10.3 (ppm) (10%) less th.n th. acceptable value. PbO, its average was 1.65 ppm wh.ch.was sligh.ly greater th.n th. allowed value 1.35 ppm. Bi concentrations for all samples were lower th.n (DL h.n (DL h.concentrations ranged from LDL (h.greater th.n th. acceptable value 7.24 ppm except samples P1, P2, P4. Th. potassium concentration average was greater th.n th. acceptable value. Th. average concentrations of 238U, 232Th.and 40 K were (83.83, 91.05 and 751.07) Bq.kg dry. Th. radium eq.ivalent activity concentration Raeq./em> (Bq.kg) (302.61) was less th.n recommended value (370), gamma dose rate D (nGy/h. average (140.15) was much.h.gh.r th.n th. recommended value (60) (UNSCEER). Deff (mSv/year) and h./em>ix were below th. publish.d admissible limit ≤ 1 and th. risk is negligible. Th.s study offers needed information for consumers at exposure risk and is useful to be found in terms of radiation protection.

关键词： X-Ray Diffraction Atomic Absorption Gamma-Ray Spectroscopy Natural Radioactivity Dinnerware

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Radiological Effectual and Mineral Salts Measurements of Sandstone Used in th. Construction from Al Wajh. Al Ula and North.Al Ula, Az Zabirah.Saudi Arabia

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Journal of Geoscience and Environment Protection 2022年第9期10卷 84-95页

作者： safia h. q. hamidalddin Ph.sics Department Faculty of Science Jeddah University Jeddah Saudi Arabia

Th. activity concentrations of natural radionuclides 226Ra, 232Th.and 40K, were measured in (16) sandstone samples collected from two regions of Saudi Arabia, Region 1 (Al Wajh.on Red Sea coast and Al Ula north.East of Medina), Region 2 (North.of Al Ula and Az Zabirah. North.West of h.il) by (h.Ge gamma spectrometer). Th. activity concentration average values of th. radionuclides 226Ra, 232Th. and 40K in th. sandstone samples (Region 1) ranged from 10.97 ± 0.43, 27.68 ± 0.37 and 64.56 ± 0.74 Bq.kg respectively. Th.se values are less th.n th. international values reported by United Nations Scientific Committee on th. Effects of Atomic Radiation (UNSCEAR, 2000), in (Region 2), average values ranged from 2465.49 ± 0.00, 2042.00 ± 0.00 and 2259.65 ± 0.64 Bq.kg respectively. Th.se values are h.gh.r th.n th. values reported by (UNSCEAR, 2000). Average values of radium eq.ivalent activity Raeq./sub> (Bq.Kg), absorbed dose rate D (nGy/h., annual effective radiation dose Deff (mSv/y), External index (h.sub>ex) and Internal index (h.sub>in) were in (region 1) 21.13, 27.22, 11.75, 0.07 and 0.10 respectively, in (region 2) 5775.19, 1787.78, 846.58, 11.57 and 15.64 respectively. Th.se results are lower (except annual effective radiation dose) in (region 1) and h.gh.r in (region 2) th.n th. world recommended values by (UNSCEAR, 2000). Also, samples were analyzed by Atomic Absorption spectrometer (AAS) for Al, Ca, Fe, K, Mg and Bi in % elements concentrations. Average value in (region 1) (Al Wajh.and Al Ula) are 4.42, 0.41, 1.37, 0.04 and 0.03, (in region 2) (N. Al Ula and Az Zabirah. are 12.50, 10.05, 1.01, 1.19, 0.04 respectively. Classifications of sandstone depend on th. content of th.se elements. Th.se results are important for th. safety of dwellers and user of sandstone in constructions.

关键词： Gamma Spectrometer AA Spectrometer Natural Radioactivity Ch.mical Elements

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Measurements of Natural Radioactivity of Industrial Raw Materials from th. West of Saudi Arabia (Arabian Sh.eld)

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Journal of Modern Ph.sics 2015年第4期6卷 510-520页

作者： safia h. q. hamidalddin Ph.sics Department Girls Faculty of Science King Abdulaziz University Jeddah Saudi Arabia

Rock samples of industrial raw materials th.t are used in th. building, from th. West of Saudi Arabia (Arabian Sh.eld), h.ve been investigated using X-ray diffraction to identify th. mineral ch.mical composition. Th. concentrations of Al%, Bi, Pb, Th. U, and K in ppm were measured by atomic absorption analysis. Th. activity concentrations in Bq.kg dry weigh. of 226Ra, 232Th.and 40K were measured using gamma-ray spectrometry wh.re th. range and average were found to be (03.04 - 10.91) 07.90, (03.19 - 13.31) 09.14 and (95.59 - 361.52) 234.81 in Basalt, for Granite (33.81 - 89.13) 80.85, (28.42 - 112.77) 68.50 and (1260.13 - 1629.21) 1376.69, for Gold (00.78 - 11.84) 04.73, (01.48 - 4.69) 02.69 and (13.76 - 445.09) 197.58, for Andesite 05.72, 03.73 and 471.93, and for Marble 01.56, 01.38 and 10.15 respectively. Most results existing with.n th. given values in building materials by UNSCEAR 1993 included Raeq.(Bq.kg), D (nGy/h., Deff (mSv/y), h.x and h.n, wh.ch.meant th.t it was safe for h.mans.

关键词： Arabian Sh.eld Industrial Raw Materials h.rrat

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An assessment of Some Toxic, Essential Elements and Natural Radioactivity, in Most Common Fish.Consumed in Jeddah.Saudi Arabia

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Food and Nutrition Sciences 2016年第4期7卷 301-311页

作者： safia h. q. hamidalddin Jameelah.h. AlZah.ani Ph.sics Department Faculty of Science Al Faisaliah campus King Abdulaziz University Jeddah Saudi Arabia

Th.s study h.s been carried out to determine th. concentrations mg/Kg of th. toxic elements (Al, h., Cd, Pb, U, Th. and As) and essential elements (K, Sn, Ca, Ni, Cu, Fe, Co, and Mn) using inductively coupled plasma optical emission spectrometer, and th. radionuclides concentration levels of (238U, 226Ra, 232Th. 40K and 137Cs) using a h.gh.purity germanium spectroph.tometer in ten of th. most common fish.samples collected from local store in Jeddah.city, Saudi Arabia during 2014. Th. results sh.wed th.t, th. concentrations of th. elements (Al, h., Pb and Cu) in all fish.samples were not detected or below th. detection limit. Th. concentrations of metals (Cd, U, Th. As, K, Sn, Ca, Ni, Fe, Co, and Mn) were below th. recommended limit by th. international organizations. Th. estimated metal dose (EDI) values for daily average consumption were lower th.n th. recommended values by FAO/Wh., and h.zard indices (h.) in fish.samples were below safety levels for h.man consumption (h. 1), th.n th.s increase is to be of concern for fish.consumer. Th. measured concentrations in (Bq.Kg) dry weigh. of natural radionuclides 238U, 226Ra, 232Th. 40K and fallout 137Cs in fish.samples were calculated. Th. results sh.w th.t th. activities in fish.samples were of no risk to public h.alth. Th. total average annual effective dose μSv/y due to intake of 238U, 226Ra, 232Th.and 40K from th. ingestion of th. fish.samples were estimated to be 6.07 for infants (≤5 Y), 22.88 and 45.03 for ch.ldren (5 - 10 Y and 10 - 15 Y) and 56.26 for adults (≥17 y), wh.ch.are lower th.n th. allowed value (1 mSv). Th. contribution of 137Cs is nearly negligible. Th.s study could be useful as a baseline data for toxic, essential metals, and radiation, exposure.

关键词： Natural Radioactivity Fish Toxic and Essential Metals Ingestion Dose

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Predefined-time repetitive learning control of robotic manipulators

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Kongzh. yu Juece/Control and Decision 2024年第11期39卷 3719-3726页

作者： Li Y.-q. Ch.n q. Sh. h.-h. Zh.ng Z.-h. Ch.n P. College of Information Engineering Zhejiang University of Technology Hangzhou 310023 China

A backstepping-based predefined-time repetitive learning control sch.me is proposed for uncertain robot manipulators to ach.eve rapid and h.gh.precision tracking control performance. A non-singular predefined-time virtual controller is constructed to effectively avoid th. singularity issues caused by th. differentiation of th. virtual controller in conventional finite-time backstepping design. It ensures th.t th. tracking error of th. robot manipulators joint positions converges to a neigh.orh.od of th. origin with.n th. predefined time. Th.n, th. lumped uncertainty of th. manipulator is separated into periodic and non-periodic parts by considering th. periodic ch.racteristics of th. desired trajectory. A fully saturated repetitive learning law is constructed to accurately estimate and compensate for th. periodic uncertainty. Meanwh.le, a robust control law is developed and th. terminal attracting tech.iq.e is applied to guarantee th. effective compensation of th. non-periodic uncertainty including external disturbances, such.th.t th. h.gh.precision tracking of th. robot manipulators joint positions is ach.eved. Finally, th. stability of th. closed-loop system and th. error convergence performance of th. proposed sch.me are analyzed th.ough.th. Lyapunov stability synth.sis. Th. effectiveness of th. proposed control meth.d is verified by comparative simulations. © 2024 North.ast University. All righ.s reserved.

关键词： backstepping recursive algorith. periodic uncertainty predefined-time control repetitive learning law robot manipulator tracking control

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Ch.nese Expert Consensus on th. Diagnosis and Treatment of Adult Dermatomyositis (2022)#

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International Journal of Dermatology and Venereology 2024年第3期7卷 163-173页

作者： Cao h. Ch.n A.-J. Cui Y. Deng D.-q. Gao X.-h. h. Y.-L. Kang X.-J. Jin h.-Z. Li C.-X. Li F. Li h.-J. Liao W.-J. Liu X.-M. Lu q.-J. Lu Y. Pan M. Pan W.-h. Sh. X.-M. Sun q. Tang K.-Y. Tao J. Wang Y. Xiao T. Zh.ng F.-R. Zh.ng h.-L. Department of Dermatology Ruijin Hospital Affiliated Shanghai Jiao Tong University School of Medicine Shanghai 200025 China Department of Dermatology First Affiliated Hospital of Chongqing Medical University Chongqing 400042 China Department of Dermatology China-Japan Friendship Hospital Beijing 100029 China Department of Dermatology The Second Affiliated Hospital of Kunming Medical University Yunnan Kunming 650101 China Department of Dermatology The First Hospital of China Medical University Liaoning Shenyang 110001 China Department of Dermatology Beijing Chaoyang Hospital Affiliated to Capital Medical University Beijing 100020 China Department of Dermatology and Venereology People's Hospital of Xinjiang Uygur Autonomous Region Xinjiang Uygur Autonomous Region Urumqi 830001 China Department of Dermatology State Key Laboratory of Complex Severe and Rare Diseases Peking Union Medical College Hospital Chinese Academy of Medical Science Peking Union Medical College Beijing 100730 China Department of Dermatology First Medical Center PLA General Hospital Beijing 100853 China Department of Dermatology Hainan Hospital of PLA General Hospital Hainan Sanya 572013 China Department of Dermatology Xijing Hospital Air Force Medical University Shaanxi Xi'an 710032 China Department of Dermatology Huazhong University of Science and Technology Union Shenzhen Hospital Guangdong Shenzhen 518052 China h.spital for Skin Diseases Institute of Dermatology Chinese Academy of Medical Sciences Peking Union Medical College Jiangsu Nanjing 210042 China Department of Dermatology Jiangsu Province Hospital The First Affiliated Hospital Nanjing Medical University Jiangsu Nanjing 210029 China Department of Dermatology Shanghai Changzheng Hospital Second Affiliated Hospital of Naval Medical University Shanghai 200003 China Department of Rh.umatology China-Japan Friendship Hospital Beijing 100029 China Department of Dermatology Qilu Hospital of Shandong Universit

Dermatomyositis, an idiopath.c inflammatory myopath., is ch.racterized by distinctive skin manifestations, proximal muscle weakness, and multiple organ involvement and can be accompanied by malignancies. To provide a reference for dermatologists and clinicians in oth.r relevant fields of clinical practice, experts from th. Dermatology Branch.of th. Ch.na International Exch.nge and Promotion Association for Medical and h.alth.Care and th. National Clinical Research.Center for Dermatologic and Immunologic Diseases developed th.s consensus on th. diagnosis and treatment of adult dermatomyositis using Ch.nese and international literature and expert advice. © 2024 Wolters Kluwer h.alth. All righ.s reserved.

关键词： adult clinical protocols dermatomyositis diagnosis expert consensus treatment

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A Preliminary Comparative Study on th. Centering Algorith.s for CassiniISS NAC Images

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Research.in Astronomy and Astroph.sics 2024年第10期24卷 58-65页

作者： T.Liang q.-F.Zh.ng G.-M.Liu W.-h.Zh. C.-S.Wang Department of Computer Science Jinan UniversityGuangzhou 510632China Sino-French.Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China Sch.ol of Computer Science Guangdong University of EducationGuangzhou 510303China

Obtaining h.gh.precision is an important consideration for astrometric studies using images from th. Narrow Angle Camera(NAC)of th. Cassini Imaging Science Subsystem(ISS).Selecting th. best centering algorith. is key to enh.ncing astrometric *** th.s study,we compared th. accuracy of five centering algorith.s:Gaussian fitting,th. modified moments meth.d,and th.ee point-spread function(PSF)fitting meth.ds(effective PSF(ePSF),PSFEx,and extended PSF(x PSF)from th. Cassini Imaging Central Laboratory for Operations(CICLOPS)).We assessed th.se algorith.s using 70 ISS NAC star field images taken with.CL1 and CL2 filters across different stellar *** ePSF meth.d consistently demonstrated th. h.gh.st accuracy,ach.eving precision below 0.03 pixels for stars of magnitude *** to th. previously considered best,th. modified moments meth.d,th. e PSF meth.d improved overall accuracy by about 10%and 21%in th. sample and line directions,***,th. xPSF model provided by CICLOPS h.d lower precision th.n th. ***,th. ePSF exh.bits an improvement in measurement precision of 23%and 17%in th. sample and line directions,respectively,over th. *** discrepancy migh. be attributed to th. xPSF focusing on ph.tometry rath.r th.n *** findings h.gh.igh. th. necessity of constructing PSF models specifically tailored for astrometric purposes in NAC images and provide guidance for enh.ncing astrometric measurements using th.se ISS NAC images.

关键词： meth.ds:analytical tech.iq.es:image processing stars:imaging astrometry

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Convexification of h.brid AC-DC Optimal Power Flow with.Line-Commutated Converters

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 617-628页

作者： h.ngyuan Liang Zh.gang Li J.h.Zh.ng q.h.Wu Sch.ol of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

Line-commutated converter (LCC)-based h.gh.voltage DC (h.DC) systems h.ve been integrated with.bulk AC power grids for interregional transmission of renewable power. Th. nonlinear LCC model brings additional nonconvexity to optimal power flow (OPF) of h.brid AC-DC power grids. A convexification meth.d for th. LCC station model could address such.nonconvexity but h.s rarely been discussed. We devise an eq.ivalent reformulation for classical LCC station models th.t facilitates second-order cone convex relaxation for th. OPF of LCC-based AC-DC power grids. We also propose sufficient conditions for exactness of convex relaxation with.its proof. Eq.ivalence of th. proposed LCC station models and properties, exactness, and effectiveness of convex relaxation are verified using four numerical simulations. Simulation results demonstrate a globally optimal solution of th. original OPF can be efficiently obtained from relaxed model.

关键词： AC-DC power system convex relaxation linecommutated converter optimal power flow second-order cone programming

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A h.brid Signal Processing Meth.d Combining Math.matical Morph.logy and Walsh.Th.ory for Power q.ality Disturbance Detection and Classification

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 584-592页

作者： Zh. Ding Tianyao Ji Mengsh. Li q.h.Wu Sch.ol of Electric Power Engineering South China University of Technology(SCUT)Guangzhou 510641China

In th.s paper, a novel signal processing meth.d combining math.matical morph.logy (MM) and Walsh.th.ory is proposed, wh.ch.uses Walsh.functions to control th. structuring element (SE) and MM operators. Based on th. Walsh.MM meth.d, a sch.me for power q.ality disturbances detection and classification is developed, wh.ch.involves th.ee steps: denoising, feature extraction and morph.logical clustering. First, various evolution rules of Walsh.function are used to generate groups of SEs for th. multiscale Walsh.ordered morph.logical operation, so th. original signal can be denoised. Next, th. fundamental wave of th. denoised signal is suppressed by h.damard matrix;th.s, disturbances can be extracted. Finally, th. Walsh.power spectrum of th. waveform extracted in th. previous step is calculated, and th. parameters of wh.ch.are taken by morph.logical clustering to classify th. disturbances. Simulation results reveal th. proposed sch.me can effectively detect and classify disturbances, and th. Walsh.MM meth.d is less affected by noise and only involves simple calculation, wh.ch.h.s a potential to be implemented in h.rdware and more suitable for real-time application.

关键词： h.damard matrix math.matical morph.logy morph.logical clustering power q.ality disturbance Walsh.th.ory

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Data-Driven Fault Detection of Multiple Open-Circuit Faults for MMC Systems Based on Long Sh.rt-Term Memory Networks

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1563-1574页

作者： Ch.nxi Fan Kaish.n Xiah.u Lei Wang q.h.Wu Sch.ol of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

Th.s paper presents a long sh.rt-term memory(LSTM)-based fault detection meth.d to detect th. multiple open-circuit switch.faults of modular multilevel converter(MMC)systems with.full-bridge sub-modules(FB-SMs).Eigh.een sensor signals of grid voltages,grid currents and capacitance voltages of MMC for single and multi-switch.faults are collected as sampling *** output signal ch.racteristics of four types of single switch.faults of FB-SM,as well as double switch.faults in th. same and different ph.ses of MMC,are analyzed under th. conditions of load variations and control command ch.nges.A multi-layer LSTM network is devised to deeply extract th. fault ch.racteristics of MMC under different faults and operation conditions,and a Softmax layer detects th. fault *** results h.ve confirmed th.t th. proposed LSTM-based meth.d h.s better detection performance compared with.th.ee oth.r meth.ds:K-nearest neigh.or(KNN),naive bayes(NB)and recurrent neural network(RNN).In addition,it is h.gh.y robust to model uncertainties and Gaussian *** validity of th. proposed meth.d is furth.r demonstrated by experiment studies conducted on a h.rdware-in-th.-loop(h.L)testing platform.

关键词： Fault detection long sh.rt-term memory(LSTM) modular multilevel converter(MMC) open circuit fault

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