Dynamic modeling of electrochemical systems using linear graph theory

The final publication is available at Elsevier via http://dx.doi.org/10.1016/j.jpowsour.2011.08.065 © 2011. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/An electrochemical cell is a multidisciplinary system which involves complex chemical, electrical, and thermodynamical processes. The primary objective of this paper is to develop a linear graph-theoretical modeling for the dynamic description of electrochemical systems through the representation of the system topologies. After a brief introduction to the topic and a review of linear graphs, an approach to develop linear graphs for electrochemical systems using a circuitry representation is discussed, followed in turn by the use of the branch and chord transformation techniques to generate final dynamic equations governing the system. As an example, the application of linear graph theory to modeling a nickel metal hydride (NiMH) battery will be presented. Results show that not only the number of equations are reduced significantly, but also the linear graph model simulates faster compared to the original lumped parameter model. The approach presented in this paper can be extended to modeling complex systems such as an electric or hybrid electric vehicle where a battery pack is interconnected with other components in many different domains.Natural Sciences and Engineering Research Council of Canada (NSERC)ToyotaMaplesof

A survey of mathematics-based equivalent-circuit and electrochemical battery models for hybrid and electric vehicle simulation

The final publication is available at Elsevier via http://doi.org/10.1016/j.jpowsour.2014.01.057 © 2014. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/In this paper, we survey two kinds of mathematics-based battery models intended for use in hybrid and electric vehicle simulation. The first is circuit-based, which is founded upon the electrical behaviour of the battery, and abstracts away the electrochemistry into equivalent electrical components. The second is chemistry-based, which is founded upon the electrochemical equations of the battery chemistry.Natural Sciences and Engineering Research Council (NSERC) of Canada, Toyota, and MapleSoft

Physics-Based Models, Sensitivity Analysis, and Optimization of Automotive Batteries

Replicated with permission by SAE Copyright © 2017 SAE International. Further distribution of this material is not permitted without prior permission from SAE.The analysis of nickel metal hydride (Ni-MH) battery performance is very important for automotive researchers and manufacturers. The performance of a battery can be described as a direct consequence of various chemical and physical phenomena taking place inside the container. In this paper, a physics-based model of a Ni-MH battery will be presented. To analyze its performance, the efficiency of the battery is chosen as the performance measure, which is defined as the ratio of the energy output from the battery and the energy input to the battery while charging. Parametric sensitivity analysis will be used to generate sensitivity information for the state variables of the model. The generated information will be used to showcase how sensitivity information can be used to identify unique model behavior and how it can be used to optimize the capacity of the battery. The results will be validated using a finite difference formulation.Financial support for this work has been provided by the Natural Sciences and Engineering Research Council of Canada (NSERC), Toyota, and Maplesoft

Development of a Microscopic Traffic Simulator for Inter-Vehicle Communication Application Research

This paper describes the development of a microscopic traffic simulator purposely designed for ITS researchers studying inter-vehicle communication (IVC) concepts and applications in large traffic networks. The simulator can represent real life vehicles within the simulation by using data from vehicle Global Positioning System (GPS) receivers, enabling validation of theories with real vehicle data. The software is developed on top of the existing microscopic traffic simulator VISSIM with the added flexibility of modelling and efficiently handling communication between large numbers of vehicles. This along with the software architecture was discussed in detail

New records and morphological assessments of long-nosed fruit bats (chiroptera: pteropodidae: Macroglossus spp.) from Vietnam

Long-nosed fruit bat is a common name of the genus Macroglossus which comprises two species: Dagger-toothed long-nosed fruit bat (M. minimus) and Greater long-nosed fruit bat (M. sobrinus). These two species were rarely recorded from Vietnam or neighboring countries. Within Vietnam, M. minimus has been recorded only from two localities in southern Vietnam while M. sobrinus was known from all northern, central and southern regions of the country. Morphological features of these species in Vietnam were poorly documented in previous publications. With results from a rapid examination of all specimens and recently captured individuals, we here confirm that M. sobrinus is distinctively larger than M. minimus in all external and craniodental measurements. Two species are also distinguishable by their nostril shapes and mandible symphyses. This paper provides new distributional records of both M. sobrinus and M. minimus from Vietnam with remarks on their ecology and habitats.

GHI NHẬN ĐẦU TIÊN VỀ ĐỘC TÍNH CỦA LOÀI VI KHUẨN LAM PLANKTOHRIX RUBESCENS PHÂN LẬP TỪ AO NUÔI CÁ TỈNH SÓC TRĂNG

Cyanobacteria and their toxicity are of environmental quality and ecological health concerns. This study aimed to determine the toxicity of the cyanobacterium Planktothrix rubescens from Vietnam. The cyanobaccterial samples from a fish pond in Soc Trang province were collected and brought to the laboratory for morphological species indentification and isolation for culture. The extracts of the cyanobacterium, P. rubescens, were used for microcystins characterization and toxicity testing on a micro-crustacean, Daphnia magna. The results contributed the first photos and morphological description on the cyanobacterium P. rubescens from Vietnam. The Enzyme Linked Immunoabsorbent Assay (ELISA) analysis indicated that all five strains of P. rubescens could produce microcystins at the concentrations of 0.06-0.42 µg/g dried weight. The chronic exposure of D. magna to the extract of P. rubescens, strain S1, revealed that the survival of the animal was strongly reduced. The toxicity of the extract to D. magna showed that there should be toxic sencondary metabolites other than microcystins in the extract. This study contributed the scientific information on the biodiversity and toxicity of cyanobacteria from Vietnam.Vi khuẩn lam và độc tính của nó là một trong những mối quan ngại liên quan đến chất lượng môi trường và sức khỏe sinh thái. Nghiên cứu này nhằm mục tiêu xác định độc tính của loài vi khuẩn lam Planktothrix rubescens có nguồn gốc Việt Nam. Mẫu vi khuẩn lam trong ao nuôi cá ở tỉnh Sóc Trăng được thu và mang về phòng thí nghiệm phục vụ việc định danh trên cơ sở hình thái học và phân lập để nuôi lấy sinh khối. Dịch chiết của loài P. rubescens được dùng để phân tích độc tố microcystins và dùng để thử nghiệm độc tính trên loài vi giáp xác Daphnia magna. Kết quả nghiên cứu đã đóng góp hình ảnh và mô tả hình thái đầu tiên cho loài vi khuẩn lam P. rubescens có nguồn gốc Việt Nam. Phân tích bằng ELISA (Enzyme Linked Immunoabsorbent Assay) đã cho thấy cả 5 chủng thuộc loài P. rubescens đều có thể 3 sản sinh độc tố microcystins với nồng độ từ 0,06 – 0,42 µg/g trọng lượng khô. Phơi nhiễm mãn tính D. magna với dịch chiết của P. rubescens, chủng S1, được quan sát và sức sống của sinh vật bị suy giảm đáng kể. Độc tính của dịch chiết đối với D. magna cho thấy trong dịch chiết ắt hẳn có chứa hợp chất thứ cấp khác có độc đối với vi giáp xác. Nghiên cứu này đóng góp thêm thông tin khoa học về đa dạng sinh học và độc học sinh thái của VKL có nguồn gốc Việt Na

Bilateral Heterogeneity in an Upwelling Mantle via Double Subduction of Oceanic Lithosphere

Vietnam is a major field of Cenozoic volcanism in Southeast (SE) Asia. Two contrasting models have been proposed to explain the mantle upwelling and volcanism in this region; collision of the Indian and Eurasian continents or subduction of the Pacific or Indo-Australian oceanic lithosphere. To place constraints on the origin of the intraplate volcanism in SE Asia, new geochronological and geochemical data for Cenozoic basalts in Vietnam are presented. Based largely on Sr-Nd-Pb isotope systematics, it was found that the sources of basalts from Central and Southern Vietnam are chemically distinct forming a sharp boundary at 13.5°N. The basalts north of the boundary show isotopic features similar to Enriched Mantle type 2 (EM2) ocean island basalts. Whereas the basalts south of the boundary show isotopic features similar to Enriched Mantle type 1 (EM1) ocean island basalts. The EM1 and EM2 basalts display positive Sr anomalies and elevated Pb/Ce and Th/La ratios, respectively. Such features suggest the origins of the sources through the recycling of deeply-subducted crustal lithologies. Furthermore, subduction of dense oceanic lithosphere can induce a convecting cell in the upper mantle. Therefore, we suggest that the chemically different basalts from Central and Southern Vietnam represent the surface expression of melting in two different convecting cells, one is driven by subduction of the Pacific plate and the other by subduction of the Indo-Australian plate

An Analysis of Shoreline Changes Using Combined Multitemporal Remote Sensing and Digital Evaluation Model

Cua Dai estuary belonged to Quang Nam province is considered to be one of the localities of Vietnam having a complex erosion and accretion process. In this area, sandbars are recently observed with lots of arguments about the causes and regimes of formation. This could very likely result of not reliable source of information on shoreline evolution and a lack of historical monitoring data. Accurately identification of shoreline positions over a given period of time is a key to quantitatively and accurately assessing the beach erosion and accretion. The study is therefore to propose an innovative method of accurately shoreline positions for an analysis of coastal erosion and accretion in the Cua Dai estuary. The proposed technology of multitemporal remote sensing and digital evaluation model with tidal correction are used to analyse the changes in shoreline and estimate the rate of erosion and accretion. An empirical formula is, especially, exposed to fully interpret the shoreline evolution for multiple scales based on a limitation of satellite images during 1965 to 2018. The results show that there is a significant difference of shoreline shift between corrections and non-corrections of tidal. Erosion process tends to be recorded in the Cua Dai cape located in the Cua Dai ward, especially in the An Luong cape located in the Duy Hai commune with the length of 1050 m. Furthermore, it is observed that there is much stronger erosion in the north side compared with south side of Cua Dai estuary

The results of deep magnetotelluric sounding for studying the Nha Trang - Tanh Linh fault

The profile of deep magnetotelluric sounding (MT) from Duc Trong - Tuy Phong has been carried out in Lam Dong and Binh Thuan  provinces. The length of the Duc Trong - Tuy Phong profile is about 80 km with 15 stations and the distance between the stations measures about 5 km. Two-dimensional MT inversion was used to find a resistivity model that fits the data. The 2D resistivity model allows determining position and development formation of the Nha Trang - Tanh Linh  fault. This is the deep fault, which is showed by the boundaries of remarkable change of resistivity. In the near surface of the Earth (from ground to the depth of 6 km), the angle of inclination of this fault is about 60o; in the next part, the direction of the Nha Trang - Tanh Linh  faut is vertical. Geoelectrical section of the Nha Trang - Tanh Linh  profile shows that the resistivity of mid-crust is higher than that of lower-crust and of upper-crust

Development of Daphnia magna under exposure to the xenobiotic octylphenol: Research article

Xenobiotics are of human and environmental concerns due to their potential toxicity. Octylphenol is one of the very common and daily used xenobiotics in door and out door activities of human beings. Toxicity of octylphenol to aquatic organisms, especially to zooplankton (e.g. Daphnia magna) was investigated but not fully understood. In this study we evaluated the chronic effects of octylphenol at the concentrations of 5, 50 and 500 μg L-1 on Daphnia magna over a period of 14 days. The results showed that low concentration of octylphenol (5 μg L-1) stimulated the maturation while high concentrations of the chemical (50 and 500 μg L-1) caused a significant mortality to the Daphnia. Besides, all the tested concentrations of octylphenol had serious impacts on fecundity and growth of the animals. Investigations on the presence, distribution, fate and toxicity of xonobiotics including octylphenol in the developing country environment are suggested for human, environmental and ecological health protection.Những hợp chất tổng hợp đang là mối quan ngại cho con người và môi trường vì khả năng gây độc của chúng. Octylphenol là một trong những hợp chất tổng hợp được sử dụng phổ biến và thường xuyên trong những hoạt động của con người trong nhà và ngoài trời. Độc tính của octylphenol đối với thủy sinh vật, đặc biệt đối với động vật phù du (vd. Daphnia magna) mặc dù đã được nghiên cứu nhưng vẫn chưa được hiểu biết đầy đủ. Trong nghiên cứu này, chúng tôi đánh giá ảnh hưởng mãn tính của octylphenol ở các nồng độ 5, 50 và 500 μg/lít lên Daphnia magna trong thời gian 14 ngày. Kết quả cho thấy ở nồng độ octylphenol thấp (5 μg/lít) kích thích sự thành thục của sinh vật trong khi ở nồng độ cao hơn (50 và 500 μg/lít) gây chết đáng kể Daphnia. Bên cạnh đó, tất cả các nồng độ ocytlphenol dùng trong thí nghiệm gây ảnh hưởng nghiêm trọng lên sức sinh sản và sinh trưởng của sinh vật. Nghiên cứu về sự hiện diện, phân bố, phát tán và độc tính của những chất tổng hợp bao gồm octylphenol ở các nước đang phát triển nên được tiến hành vì mục tiêu bảo vệ sức khỏe con người, môi trường và hệ sinh thái