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Effects of used lubricating oil on two mangroves Aegiceras corniculatum and Avicennia marina

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Journal of Environmental Sciences 2007年第11期19卷 1355-1360页

作者： YE Yong tam N FY State Key Laboratory of marine Environmental Science Xiamen University Xiamen 361005 China Department of Biology and Chemistry City University of Hong Kong Hong Kong China

An outdoor experiment was set up to investigate the effects of used lubricating oil （5 L/m^2） on Aegiceras corniculatum Blanco. and Avicennia marina （Forsk） Vierh., two salt-excreting mangroves. A. marina was more sensitive to used lubricating oil than A. corniculatum and canopy-oiling resulted in more direct physical damage and stronger lethal effects than base-oiling. When treated with canopy-oiling, half of A. corniculatum plants survived for the whole treatment time （90 d）; but, for A. marina, high mortality （83%） resulted from canopy-oiling within 3 weeks and no plants survived for 80 d. Base-oiling had no lethal effects on A. corniculatum plants even at the termination of this experiment, but 83% of A. marina plants died 80 d after treatment. Forty days after canopyoiling, 93% ofA. corniculatum leaves fell and no live leaves remained on A. marina plants. By the end of the experiment, base-oiling treatment resulted in about 45% ofA. corniculatum leaves falling, while all A. mar/na leaves and buds were burned to die. Lubricating oil resulted in physiological damage to A. corniculatum leaves, including decreases in chlorophyll and carotenoid contents, nitrate reductase, peroxidase and superoxide dismutase activities, and increases in malonaldehyde contents. For both species, oil pollution significantly reduced leaf, root, and total biomass, but did not significantly affect stem biomass. Oil pollution resulted in damage to the xylem vessels of fine roots but not to those of mediate roots.

关键词： used lubricating oil mangrove Aegiceras corniculatum Avicennia marina

Efficient Technique for Image Cryptography Using Sudoku Keys

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Computers, materials & Continua 2023年第10期77卷 1325-1353页

作者： m.A.P.manimekalai m.Karthikeyan I.Thusnavis Bella mary K.martin Sagayam Ahmed A Elngar Unai Fernandez-Gamiz hatıra Günerhan Department of ECE Karunya Institute of Technology and SciencesCoimbatore641114India Faculty of Computer and Artificial Intelligence Beni-Suef UniversityBeni-Suef62511Egypt Nuclear Engineering and Fluid mechanics Department University of the Basque CountryBilbao48940Spain Department of mathematics Faculty of EducationKafkas UniversityKars36100Turkey

This paper proposes a cryptographic technique on images based on the Sudoku *** is a number puzzle,which needs applying defined protocols and filling the empty boxes with *** a small size of numbers as input,solving the sudoku puzzle yields an expanded big size of numbers,which can be used as a key for the Encryption/Decryption of *** this way,the given small size of numbers can be stored as the prime key,which means the key is compact.A prime key clue in the sudoku puzzle always leads to only one solution,which means the key is always *** feature is the background for the paper,where the Sudoku puzzle output can be innovatively introduced in image *** solution is expanded to any size image using a sequence of expansion techniques that involve filling of the number matrix,Linear X-Y rotational shifting,and reverse shifting based on a standard zig-zag *** crypto key for an image dictates the details of positions,where the image pixels have to be *** is made at two levels,namely pixel and sub-pixel(RGB)levels for an image,with the latter having more effective *** brought-out technique falls under the Image scrambling method with partial *** metrics are impressive and are given by a Histogram deviation of 0.997,a Correlation coefficient of 10−2 and an NPCR of 99.98%.Hence,it is evident that the image cryptography with the sudoku kept in place is more efficient against Plaintext and Differential attacks.

关键词： Sudoku image cryptography pixels performance metrics

Youth Participation at the Third UN World Conference on Disaster Risk Reduction

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International Journal of Disaster Risk Science 2015年第2期6卷 150-163页

作者： Lydia Cumiskey tam Hoang Sachi Suzuki Claire Pettigrew moa m.Herrgard Disaster Risk Reduction Working Group UN Major Group for Children&Youth Youth Beyond Disasters Water Youth Network marine and Coastal Systems Health and Safety Emergency Management and Business Continuity UnitVictoria University Standing Committee on Human Right and Peace International Federation of Medical Students’Associations Department of Engineering Tohoku University

This article summarizes and analyzes the Children & Youth Forum and youth participation in the process during and leading up to the Third UN World Conference on Disaster Risk Reduction(WCDRR) in2015. An organizing committee consisting of international students and young professionals brought together around200 young professionals and students from around the globe to exchange ideas and knowledge on reducing disaster risk, building resilient communities, and advocating for the inclusion of youth priorities within the Sendai Framework for Disaster Risk Reduction 2015–2030(SFDRR). The knowledge exchange during the Forum was structured around a Toolbox for Resilience that connected to the SFDRR section on Priorities for Action. This article presents the outcomes of these young people’s participation in the disaster risk reduction capacity building eventsand policy-making, as well as the follow-up actions envisioned by the young participants of the Forum. The voices of the younger generation were heard in the SFDRR and young people are ready to expand their actions for the framework’s effective implementation. Young people call on technical experts, donors, NGOs, agencies, governments, and academia to partner with them on this journey to create a more resilient tomorrow together.

关键词： Children & Youth Forum Disaster risk reduction SFDRR Toolbox for Resilience

Comparing material wastage levels between conventional in-situ and prefabrication construction in Hong Kong

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Journal of Harbin Institute of Technology(New Series) 2004年第5期11卷 548-551页

作者： Vivian W Ytam C m tam L Y Shen Dept. of Building and Construction City University of Hong Kong Hong Kong ChinaDept. of Building and Construction City University of Hong Kong Hong Kong ChinaDept. of Building and Construction City University of Hong Kong Hong Kong China

Generation of construction wastes constitutes a major impact to the environment. Studies have been directed toward reducing wastes of the various construction processes. However, contractors in Hong Kong are rather conservative and lack motivation to develop new technology for waste minimization. This paper examines the benefits of using prefabrication in reducing material wastage levels for some traditional in-situ trades such as concreting, rebar fixing, bricklaying, drywall, plastering, screeding and tiling in Hong Kong. By measuring thirty construction projects, it is been found that waste levels of all major construction trades can be effectively reduced. This is particularly significant in the trade of plastering where 100% saving can be achieved after adopting prefabrication. The standardized design of the building can also be useful in the adoption of prefabrication for private housing projects.

关键词： prefabrication conventional in-situ trades material wastage environment

Hydrogeological Characteristics of a Karst mountainous Catchment in the Northwest of Vietnam

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Acta Geologica Sinica(English Edition) 2001年第3期75卷 260-268页

作者： V.T.tam T.m.N.VU O.BATELAAN Research Institute of Geology and mineral Resources Ministry of Industry VietnamResearch Institute of Geology and Mineral Resources Ministry of Industry VietnamDepartment of Hydrology and Hydraulic Engineering Free University Brussels Belgium

This paper presents a preliminary assessment of the hydrogeological characteristics of a karst mountainous catchment, the Suoi muoi River catchment, in the northwest of Vietnam. The catchment is located at 600–700 m a.s.l. and covers an area of 284 km. Exposed limestone occupies 32% of the total catchment area. Various types of assessments have been carried out, including geological and hydrogeological field surveys, cave surveys, dye-tracer tests, meteorological and surface water monitoring. Geological studies and cave surveys have identified the most important active cave/conduit systems within the catchment. Although these data are essential, they are insufficient to make a comprehensive appraisal of the hydrologic nature of the catchment under interest. An attempt was made to calculate a global water balance of the catchment, based on short-term (15 months) meteorological and streamflow records. The results show that, despite the existence of a number of substantial cavern conduit systems, the groundwater system of the catchment is governed by the fracture/fissure matrix. The cavern conduit systems only collect groundwater from the adjacent fracture matrix and/or connect topographically isolated surface watercourses. The groundwater storage of the cavern conduit systems appears to be regionally insignificant in comparison with the governed fracture matrix groundwater system.

关键词： karst hydrology geology lowflow

Investigating the impacts of urban speed limit reduction through microscopic traffic simulation

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Communications in Transportation Research 2021年第1期1卷 144-157页

作者： mánuel Gressai Balázs Varga tamás Tettamanti István Varga Dept.of Control for Transportation and Vehicle Systems Fac.of Transportation Engineering and Vehicle EngineeringBudapest University of Technology and Economics

Road traffic congestion has become an everyday phenomenon in today's cities all around the *** reason is clear:at peak hours,the road network operates at full *** this way,growing traffic demand cannot be satisfied,not even with traffic-responsive signal *** external impacts of traffic congestion come with a serious socio-economic cost:air pollution,increased travel times and fuel consumption,stress,as well as higher risk of *** tackle these problems,a number of European cities have implemented reduced speed limit ***,a general urban speed limit measure is in preparatory phase in Budapest,*** this context,a complex preliminary impact assessment is needed using a simulated *** typical network parts of Budapest were analyzed with microscopic traffic *** results revealed that speed limits can affect traffic differently in diverse network types indicating that thorough examination and preparation works are needed prior to the introduction of speed limit reduction.

关键词： Speed limit reduction microscopic traffic simulation Emission Traffic analysis

Intelligent Resource Allocations for Software-Defined mission-Critical IoT Services

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Computers, materials & Continua 2022年第11期73卷 4087-4102页

作者： Chaebeen Nam Sa math Prohim tam Seokhoon Kim Department of Software Convergence Soonchunhyang UniversityAsan31538Korea Department of Computer Software Engineering Soonchunhyang UniversityAsan31538Korea

Heterogeneous Internet of Things(IoT)applications generate a diversity of novelty applications and services in next-generation networks(NGN),which is essential to guarantee end-to-end(E2E)communication resources for both control plane(CP)and data plane(DP).Likewise,the heterogeneous 5th generation(5G)communication applications,including mobile Broadband Communications(mBBC),massive machine-Type Commutation(mmTC),and ultra-reliable low latency communications(URLLC),obligate to perform intelligent Quality-of-Service(QoS)Class Identifier(QCI),while the CP entities will be suffered from the complicated massive HIOT ***,the existing management and orchestration(mANO)models are inappropriate for resource utilization and allocation in large-scale and complicated network *** cope with the issues mentioned above,this paper presents an adopted software-defined mobile edge computing(SDmEC)with a lightweight machine learning(mL)algorithm,namely support vector machine(SVm),to enable intelligent mANO for real-time and resource-constraints IoT applications which require lightweight computation ***,the SVm algorithm plays an essential role in performing QCI ***,the software-defined networking(SDN)controller allocates and configures priority resources according to the SVm classification ***,the complementary of SVm and SDmEC conducts intelligent resource mANO for massive QCI environments and meets the perspectives of mission-critical communication with resource constraint *** on the E2E experimentation metrics,the proposed scheme shows remarkable outperformance in key performance indicator(KPI)QoS,including communication reliability,latency,and communication throughput over the various powerful reference methods.

关键词： mobile edge computing Internet of Things software defined networks traffic classification machine learning resource allocation

Notes on m-Estimation in Exponential Signal models

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Communications in mathematics and Statistics 2021年第2期9卷 139-151页

作者： Shu Ding Yuehua Wu Kwok-Wai tam School of Economics Hefei University of TechnologyHefeiChina Department of mathematics and Statistics York UniversityTorontoONCanada Department of mathematics Portland State UniversityPortlandORUSA

An m-estimation of the parameters in an undamped exponential signal model was proposed in Wu and tam(IEEE Trans Signal Process 49(2):373–380,2001),and the estimation was shown to be consistent under mild *** this paper,the limiting distributions of the m-estimators are *** is shown that they are asymptotically normally distributed under similar conditions as assumed in Wu and tam(IEEE Trans Signal Process 49(2):373–380,2001).In addition,a recursive algorithm for computing the m-estimators of frequencies is proposed,and the strong consistency of these estimators is *** Carlo simulation studies using Huber’sρfunction are also provided.

关键词： Exponential signal model m-estimation Limiting distribution Recursive algorithm Consistency

Effects of NaOH Concentrations on Properties of the Thermal Power Plant Ashes-Bricks by Alkaline Activation

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Journal of Wuhan University of Technology(materials Science) 2020年第1期35卷 131-139页

作者： Ngo Si-Huy Le Thi Thanh-tam Huynh Trong-Phuoc Department of Engineering and Technology Hong Duc UniversityNo.565Quang Trung StreetDong Ve WardThanh Hoa City 440000Viet Nam Department of Rural Technology College of Rural DevelopmentCan Tho UniversityCampus II3/2 StreetNinh Kieu DistrictCan Tho City 900000Viet Nam

The use of the thermal power plant ashes including fly ash(FA) and bottom ash(BA) for producing unfired building bricks(UBB) using sodium hydroxide(NaOH) solution as an alkaline activator was investigated. A low applied forming pressure of 0.5 mPa and various NaOH concentrations of 5, 8, 10, and 12 m were used for the preparation of brick samples with different solution-to-binder(S/B) ratios of 0.35 and 0.40. The bricks were subjected to various test programs with reflecting the effect of both NaOH concentrations and S/B ratios on the brick’s properties. The compressive strength, unit weight, ultrasonic pulse velocity, and thermal conductivity of bricks increased with increasing NaOH concentration, whereas the contrary trend was found with increasing S/B ratio. Also, the water absorption of bricks was observed to reduce with increasing NaOH concentration and decreasing S/B ratio. As the results, the combined utilization of both low forming pressure and coal power plant ashes can produce the UBBs with low unit weight, low heat conductivity, and acceptable strength and water absorption rate as stipulated by TCVN 6477-2016. Furthermore, the outcomes of chemical analysis and microstructure observation also demonstrate that a high concentration of the Na OH promoted the geopolymerization process. Notably, the use of NaOH solution of either 10 m or above is recommended for the production of UBBs, which are classified as grade m5.0 or higher.

关键词： unfired building brick fly ash bottom ash thermal power plant ashes sodium hydroxide solution low forming pressure