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Identification of thermal front dynamics in the northern Malacca Strait using ROMS 3D-model

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Journal of Oceanology and Limnology 2024年第1期42卷 41-57页

作者： Ku Nor Afiza Asnida Ku MANSOR Nur Hidayah ROSELI Poh Heng KOK Fariz Syafiq mohamad ali mohd Fadzil mohd AKHIR Institute of Oceanography and Environment Universiti Malaysia TerengganuKuala Nerus 21030Malaysia Faculty of Science and Marine Environment Universiti Malaysia TerengganuKuala Nerus 21030Malaysia

The thermal front in the oceanic system is believed to have a significant effect on biological *** an era of climate change,changes in heat regulation between the atmosphere and oceanic interior can alter the characteristics of this important *** the simulation results of the 3D Regional Ocean Modelling System(ROMS),we identified the location of thermal fronts and determined their dynamic variability in the area between the southern Andaman Sea and northern Malacca *** Single Image Edge Detection(SIED)algorithm was used to detect the thermal front from model-derived *** show that a thermal front occurred every year from 2002 to 2012 with the temperature gradient at the location of the front was 0.3°C/*** to the years affected by El Ni?o and negative Indian Ocean Dipole(IOD),the normal years(e.g.,May 2003)show the presence of the thermal front at every selected depth(10,25,50,and 75 m),whereas El Ni?o and negative IOD during 2010 show the presence of the thermal front only at depth of 75 m due to greater warming,leading to the thermocline deepening and enhanced *** May 2003,the thermal front was separated by cooler SST in the southern Andaman Sea and warmer SST in the northern Malacca *** higher SST in the northern Malacca Strait was believed due to the besieged Malacca Strait,which trapped the heat and make it difficult to release while higher chlorophyll a in Malacca Strait is due to the freshwater conduit from nearby rivers(Klang,Langat,Perak,and Selangor).Furthermore,compared to the southern Andaman Sea,the chlorophyll a in the northern Malacca Strait is easier to reach the surface area due to the shallower thermocline,which allows nutrients in the area to reach the surface faster.

关键词： regional ocean modelling system thermal front Andaman Sea Malacca Strait single image edge detection algorithm

Hyper Elliptic Curve Based Certificateless Signcryption Scheme for Secure IIoT Communications

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Computers, Materials & Continua 2022年第5期71卷 2515-2532页

作者： Usman ali mohd Yamani Idna Idris Jaroslav Frnda mohamad Nizam Bin Ayub Roobaea Alroobaea Fahad Almansour Nura Modi Shagari Insaf Ullah Ihsan ali Department of Computer System and Technology Faculty of Computer Science and Information TechnologyUniversity of MalayaKuala Lumpur50603Malaysia Department of Computer Science University of SwatSaidu Sharif19130Pakistan Center for Research in Mobile Cloud Computing University of MalayaKuala Lumpur50603Malaysia Department of Quantitative Methods and Economic Informatics Faculty of Operation and Economics of Transport and CommunicationsUniversity of Zilina01026 ZilinaSlovakia Department of Computer Science College of Computers and Information TechnologyTaif UniversityTaif21944Saudi Arabia Department of Computer Science College of Sciences and Arts in RassQassim UniversityBuraydah51452Saudi Arabia Department of Computer Science Hamdard Institute of Engineering and TechnologyIslamabad44000Pakistan

Industrial internet of things (IIoT) is the usage of internet of things(IoT) devices and applications for the purpose of sensing, processing andcommunicating real-time events in the industrial system to reduce the unnecessary operational cost and enhance manufacturing and other industrial-relatedprocesses to attain more profits. However, such IoT based smart industriesneed internet connectivity and interoperability which makes them susceptibleto numerous cyber-attacks due to the scarcity of computational resourcesof IoT devices and communication over insecure wireless channels. Therefore, this necessitates the design of an efficient security mechanism for IIoTenvironment. In this paper, we propose a hyperelliptic curve cryptography(HECC) based IIoT Certificateless Signcryption (IIoT-CS) scheme, with theaim of improving security while lowering computational and communicationoverhead in IIoT environment. HECC with 80-bit smaller key and parameterssizes offers similar security as elliptic curve cryptography (ECC) with 160-bitlong key and parameters sizes. We assessed the IIoT-CS scheme security byapplying formal and informal security evaluation techniques. We used Realor Random (RoR) model and the widely used automated validation of internet security protocols and applications (AVISPA) simulation tool for formalsecurity analysis and proved that the IIoT-CS scheme provides resistance tovarious attacks. Our proposed IIoT-CS scheme is relatively less expensivecompared to the current state-of-the-art in terms of computational cost andcommunication overhead. Furthermore, the IIoT-CS scheme is 31.25% and 51.31% more efficient in computational cost and communication overhead,respectively, compared to the most recent protocol.

关键词： IoT security authentication protocols hyperelliptic curve cryptography certificateless public key cryptography

Faecal sterols as sewage markers in the Langat River,Malaysia:Integration of biomarker and multivariate statistical approaches

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Journal of Environmental Sciences 2012年第9期24卷 1600-1608页

作者： Nur Hazirah Adnan mohamad Pauzi Zakaria Hafizan Juahir Masni mohd ali Centre of Excellence for Environmental Forensics Faculty of Environmental StudiesUniversiti Putra Malaysia 43400 SerdangSelangorMalaysia Department of Environmental Sciences Faculty of Environmental StudiesUniversiti Putra Malaysia43400 SerdangSelangorMalaysia School of Environmental and Natural Resource Sciences Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 BangiSelangorMalaysia

The Langat River in Malaysia has been experiencing anthropogenic input from urban, rural and industrial activities for many years. Sewage contamination, possibly originating from the greater than three million inhabitants of the Langat River Basin, were examined. Sediment samples from 22 stations （SL01-SL22） along the Langat River were collected, extracted and analysed by GC-MS. Six different sterols were identified and quantified. The highest sterol concentration was found at station SL02 （618.29 ng/g dry weight）, which situated in the Balak River whereas the other sediment samples ranged between 11.60 and 446.52 ng/g dry weight. Sterol ratios were used to identify sources, occurrence and partitioning of faecal matter in sediments and majority of the ratios clearly demonstrated that sewage contamination was occurring at most stations in the Langat River. A multivariate statistical analysis was used in conjunction with a combination of biomarkers to better understand the data that clearly separated the compounds. Most sediments of the Langat River were found to contain low to mid-range sewage contamination with some containing ＇significant＇ levels of contamination. This is the first report on sewage pollution in the Langat River based on a combination of biomarker and multivariate statistical approaches that will establish a new standard for sewage detection using faecal sterols.

关键词： sterols biomarkers surface sediments sewage pollution Langat River principal component analysis

New coating formulation for the slow release of urea using a mixture of gypsum and dolomitic limestone

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Particuology 2015年第6期13卷 62-67页

作者： Farahnaz Eghbali Babadi Robiah Yunus Suraya Abdul Rashid mohamad Amran mohd Salleh Salmiaton ali Institute of Advanced Technology Universiti Putra Malaysia Selangor 43400 Malaysia Departments of Chemical and Environmental Engineering Faculty of Engineering Universiti Putra Malaysia Selangor 43400 Malaysia

The use of urea and urea-based fertilizers has increased considerably over the past 15 years. They cur- rently account for approximately 51% of the world＇s agricultural nitrogen consumption. However, about 20-70% of the applied urea fertilizer is lost to the environment, causing serious pollution and increasing costs. These losses come from leaching, decomposition, and ammonium volatilization in the soil during handling and storage. Controlled release by coating can be used to increase urea fertilizer efficiency. We studied the use of gypsum, sulfur, and ground magnesium lime as cost-effective coating materials. All these coating materials contain nutrients required by plants. The effects of the coating composition and proportion of sealant on the rate of urea release and the crushing strength of the coated urea were investigated. We found that coated urea with the same proportion of gypsum-ground magnesium lime （GML） exhibited low urea release and high crushing strength. The performance was enhanced when using polyols as a sealant on the surface of the coated urea. A surface morphology analysis indicated a uniform and smooth surface on the coated film. The efficiency of the coated urea improved by 34.2% when using gypsum-GML （ 1：1 ratio） containing 1.1% oolvols.

关键词： Ground magnesium lime Crushing strength Rotary pan SealantPolyol

Digital Control Design for the Boiler Drum BDT921

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Journal of Mechanics Engineering and Automation 2011年第5期1卷 392-397页

作者： Tatang Mulyana mohamad Nor mohd Than Dirman Hanafi Afrodi ali Control Laboratory Department of Mechatronics and Robotics Engineering Faculty of Electric and Electronic Engineering

A boiler drum BDT921 that is installed in the Control Laboratory, Department of Mechatronics and Robotics Engineering, Faculty of Electric and Electronic Engineering, Universiti Tun Hussein Onn Malaysia (UTHM) is being used as a model plant to achieve the digital control system since its analog. Implementing a digital system to boiler quite a though work. This paper covers analysis from the experiment done to match with digital design that will be implemented to the real system. The digital control design will come up with the mathematical model and will be analyzed with MATLAB and SIMULINK software named as "Discrete Analysis of BDT921 Simulation". A proportional integral and derivative (PID) controller is being chosen as the control element in discrete form as the real system is using the same control element. The output responses behave as the second order system with a bit difference in rise times and peak times compared with data obtained from experiment. With regarding to the analysis done, the digital control can be implemented and for further viewing, to be controlled digitally with computer in the control room.

关键词：控制系统设计锅炉汽包 Simulink软件数字化控制系统 MATLAB 比例积分微分上升时间数字控制

WiFi/WiMAX Seamless Convergence with Adaptive Vertical Handover for Continuity of Internet Access

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Advances in Internet of Things 2011年第2期1卷 32-37页

作者： Rashid Abdelhaleem Saeed Hafizal mohamad Mazlan Abbas Borhanuddin mohd ali 不详

The next generation of the wireless networks will consist of several overlapping tiers. Provision of undisrupted communication to mobile users is a challenging task. Handover delay is one of the problematic issues that users are faced in the heterogeneous networks. However, in the case of both the WiMAX and the WiFi technologies which are located at the same base station (BS), the vertical handover (VHO) delay will be less as compared with the two conventional WiMAX/WiFi heterogeneous networks with two different wireless Internet service providers (WISP). Nevertheless, protocol conversion is still adding delay and jitter for data exchange between the needed two technologies. In this paper, in order to reduce the delay in the protocol conversion, a new industrial design for WiWi (WiMAX and WiFi) adaptation layer is proposed. The realization of the interworking between these two standards is discussed and evaluated. The results show that the proposed scheme-with the scenario under study- has better performance than other related works.

关键词： WiFi WiMAX Convergence Heterogeneous Network Seamless Handover

Discovery of Simple Sequence Repeat Markers through Transcriptome Analysis of Baccaurea motleyana

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Journal of Food Science and Engineering 2020年第2期10卷 33-46页

作者： Khairun Hisam Nasir Muhammad Fairuz mohd Yusof mohd Shahril Firdaus Abdul Razak Siti NorsaidahIbrahim Mira Farzana mohamad Moktar Khadijah Awang mohd Shukri Mat ali Centre for Molecular Marker Discovery and Validation(CMDV) Agri-Omic dan BioinformaticsBiotechnology and Nanotechnology Research CentreMalaysian Agricultural Research and Development Institute(MARDI)Serdang 43400SelangorMalaysia Industrial Crop Research Centre Malaysian Agricultural Research and Development Institute(MARDI)Serdang 43400SelangorMalaysia Horticulture Research Centre Malaysian Agricultural Research and Development Institute(MARDI)Serdang 43400SelangorMalaysia

Baccaurea motleyana(rambai)is underutilized fruits that are native to Malaysia,Indonesia and *** this study,a total of 54,779 unigenes identified from rambai transcriptome were used for simple sequence repeat(SSR)analysis by MIcroSAtellite(MISA).A total of 20,420 SSRs were found to be distributed within 37.27%of the total number of *** repeats represented the main type,accounting for 64.04%,followed by trinucleotide repeats(20.28%)and dinucleotide repeats(19.94%).Gene annotation to seven databases has a success ratio of 68.53%(National Center for Biotechnology Information(NCBI)protein sequences),53.68%(NCBI nucleotide sequences),27.43%(Kyoto Encyclopedia of Genes and Genome Ortholog),56.0%(SwissProt),52.44%(Protein family),53.99%(Gene Ontology)and 26.44%(Kluster of Orthologous Group).Further rambai SSRs were randomly selected and validated to ***(rambai),***(tampoi),***(jentik-jentik),***(pupor)and ***(setambun).

关键词： Baccaurea SSR transcriptome gene annotation and SSR validation