164 research outputs found
Review of two genera of freshwater crabs, Larnaudia Bott, 1966 and Neolarnaudia Türkay & Naiyanetr, 1987 (Crustacea: Decapoda: Potamidae) with redescription Neolarnaudiaphymatodes (Kemp, 1923) from Southern Vietnam
No full textABSTRACT: The occurrence of Larnaudia Bott, 1966 in southern Vietnam remains obscure. Although some previous studies described the presence of Larnaudialarnaudii A. Milne-Edwards, 1869 in Vietnam, our analysis of freshwater crab specimens collected at many locations in southern Vietnam revealed that Neolarnaudia Türkay Naiyanetr, 1987, but not Larnaudia Bott, 1966, is present in southern Vietnam. In this study, we recorded two species of Neolarnaudia, N. phymatodes (Kemp, 1923) and N. botti Türkay Naiyanetr, 1987 in southern Vietnam. Neolaurnaudia phymatodes was poorly knownsince the original description, and is, thus, re-described here. This species can be distinguished from all other Neolarnaudia species by a suite of characters; carapace broader, frontal area with many granules, supraorbital margingranulated, suborbital and pterygostomian regions and merus of third maxillipedcovered with many granules, terminal segment of Gonopod 1 strongly curved inwards and covered with many pubescences, lateral margin of telsonstrongly concaved. Citation: Do Van Tu, Dang Van Dong, Le Van Tho, Phan Doan Dang, 2017. Review of two genera of freshwater crabs, Larnaudia Bott, 1966 and Neolarnaudia Türkay Naiyanetr, 1987 (Crustacea: Decapoda: Potamidae) with redescription Neolarnaudiaphymatodes (Kemp, 1923) from Southern Vietnam. Tap chi Sinh hoc, 39(4): 398-405. DOI: 10.15625/0866-7160/v39n4.8464.*Corresponding author: [email protected], [email protected] 19 September 2017, accepted 12 December 201
The D1-triangulation in simplicial variable dimension algorithms for computing solutions of nonlinear equations
No full textNonlinear Equations
The Influence of Message Framing on Engagement with a Mobile Application for Motivating Exercise
No full textThesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 21).Mobile phone personal health monitoring software is designed to help people monitor and change their behavior. Exercise applications may measure heart rate, temperature, distance traveled, and movement. Although some of these programs incorporate behavioral theories to motivate engagement and behavior change, it is not yet clear that the devices can maintain engagement long term for individuals who are not strongly inclined to exercise already. If people do not use health apps for long periods of time - weeks, months or years instead of days - there are unlikely to be long-term health benefits. This paper describes a new mobile health application designed to motivate exercise via brisk walking: MyWalk. MyWalk delivers timely, tailored feedback messages intended to persuade additional brisk walking. An experiment was conducted to explore how message framing impacts application usage using participants who downloaded the application from an online app store. Author Keywords: Engagement, Health, Mobile, Phone, Pervasive Technology, Reinforcement, Personal Health Informatics, Design, Human-Computer Interaction. ACM Classification Keywords H5.m. Information interfaces and presentation (e.g., HCI): Miscellaneous.by Anh Dang-Viet Nguyen.M.Eng
From micro-CT TO A NURBS-based interface-enriched generalized finite element method
No full textIn the solid mechanic community, the finite element method is widely used to simulate the mechanical or thermal response of materials and structures. In most cases, conforming meshes are used to discretize the simulated geometry. However, this traditional method is not efficient in the analysis of complex microstructures, since the shape of most microstructures is quite irregular. Creating a conforming mesh with good element quality requires a tremendous amount of time and effort. Furthermore, conventional meshing techniques typically yield a large number of elements, thereby increasing the computational cost of the analysis.
In this work, a structured non-conforming mesh generation process is proposed and demonstrated for the analysis of heterogeneous materials with complex microstructures using a NURBS-based Interface-enriched Generalized Finite Element Method (NIGFEM) developed in Prof. Geubelle’s group over the past few years. The NIGFEM relies on structured meshes that do not conform to the material interfaces, and uses NURBS (Non-Uniform Rational B-Spline)-based enrichments of the finite element approximation in the elements intersected by the material interfaces. These enrichments capture the key features of the solution along the material interfaces (e.g., C0 or C-1 continuity) and provide a very accurate description of the interface geometrical features.
The proposed meshing method uses an octree structure to subdivide the computational domain iteratively. At each iteration, the topology relation between nodes, edges, and surfaces within the subdivided elements are calculated and classified into different types. A set of hierarchical mesh refinement rules are defined to continuously divide the element if they meet specific criteria. To accurately capture the material interfaces that falls inside the structured mesh grid, NURBS are used as basis functions to capture the boundary geometry shape. This hierarchical NURBS-based structured mesh can largely reduce the number of elements without sacrificing the accuracy of discretization. The method is particularly attractive for the computational analysis of real microstructures captured through X-ray tomography, as the micro-CT images are converted into a set of NURBS representations of the material interfaces using a set of steps also described in this thesis.Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2021-05-01The student, Qi Dang, accepted the attached license on 2019-03-27 at 10:48.The student, Qi Dang, submitted this Thesis for approval on 2019-03-27 at 11:08.This Thesis was approved for publication on 2019-03-28 at 11:32.DSpace SAF Submission Ingestion Package generated from Vireo submission #13458 on 2019-08-22 at 15:05:10Made available in DSpace on 2019-08-23T20:35:43Z (GMT). No. of bitstreams: 2
DANG-THESIS-2019.pdf: 3594517 bytes, checksum: d46db595c068bfaa6ea8b9a62fa45670 (MD5)
LICENSE.txt: 4205 bytes, checksum: 1d131c343c9000c240cea8efa81974fb (MD5)
Previous issue date: 2019-03-28Embargo set by: Seth Robbins for item 112099
Lift date: 2021-08-23T20:36:18Z
Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD systemU of I Only Restriction Lifted for Item 112099 on 2021-08-24T09:15:28Z
Understanding linkages between trade and water resources
No full textEmbargo set by: Seth Robbins for item 107258
Lift date: 2020-09-04T20:37:00Z
Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD systemEmbargo set by: Seth Robbins for item 107258
Lift date: 2020-09-04T20:42:08Z
Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD systemU of I Only Restriction Lifted for Item 107258 on 2020-09-05T09:15:20Z.Water is an essential input for agricultural production. Agriculture, in turn, is globalized through the trade of agricultural commodities. The relationship between international trade and water resources is an issue of great interest in the literature. Many studies focus on the relationship between trade and virtual water resources, without direct consideration of domestic, physical water resources. Now, there is a critical need to better understand the implications of trade for domestic (physical) water use. As such, the main goal of this dissertation is to understand linkages between trade and water resource both theoretically and empirically.
In this dissertation, I develop a theoretical model that emphasizes four tradeoffs involving water-use decision-making that are important yet not always considered in a consistent framework. One tradeoff focuses on competition for water among different economic sectors. A second tradeoff examines the possibility that certain types of agricultural investments can offset water use. A third tradeoff explores the possibility that the rest of the world can be a source of supply or demand for a country's water-using commodities. The fourth tradeoff concerns how variability in water supplies influences farmer decision-making. I show conditions under which trade liberalization affect water use. Two policy scenarios to reduce water use are evaluated. First, I derive a target tax that reduces water use without offsetting the gains from trade liberalization, although important tradeoffs exist between economic performance and resource use. Second, I show how subsidization of water-saving technologies can allow producers to use less water without reducing agricultural production, making such subsidization an indirect means of influencing water use decision-making. Finally, I outline conditions under which riskiness of water availability affects water use. These theoretical model results generate hypotheses that can be tested empirically in future work.
I also contribute to the debate over globalization and the environment by asking: What is the impact of trade on national water use and water quality? To address this question I employ econometric methods to quantify the causal relationship between trade openness, water use and nutrient use. Specifically, I use the instrumental variables methodology to evaluate the impact of trade openness on domestic water withdrawals in agriculture and industry, national nitrate, phosphate and potash use in agriculture. I find that a one percentage point increase in trade openness leads to a 5.21% decrease in agricultural water withdrawals. I find that trade openness reduces water use in agriculture primarily through the intensive margin effect, by leading farmers to produce more with less water, such as through the adoption of technology. I do not find evidence for extensive margin or crop mix impacts on agricultural water withdrawals. Significantly, these results demonstrate that trade openness leads to less water use in agriculture. However, for water quality side, I find that the impact of trade openness on nutrient use, if any, is very small. This is in line with previous research that shows that trade openness does not have a negative impact on the environment. Why would trade openness reduce nutrient applications in agriculture much smaller than agricultural water use? I show that the elasticity of substitution between nutrient use and capital is smaller than is the elasticity of substitution between water and capital. This suggests that agricultural inputs such as capital and labor are easier to substitute for water than they are for nutrient use. This helps to explain why the impact of trade on nutrient use is much smaller. This finding has broad scientific and policy relevance as I endeavor to untangle causal relationships in the complex global food system and determine its environmental impacts.Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2020-05-01The student, Qian Dang, accepted the attached license on 2018-04-16 at 16:07.The student, Qian Dang, submitted this Dissertation for approval on 2018-04-16 at 16:23.This Dissertation was approved for publication on 2018-04-18 at 08:30.DSpace SAF Submission Ingestion Package generated from Vireo submission #12284 on 2018-08-31 at 17:19:08Made available in DSpace on 2018-09-04T20:36:36Z (GMT). No. of bitstreams: 2
DANG-DISSERTATION-2018.pdf: 3524035 bytes, checksum: 45ed0717ada0385ccb7484b345aebdd8 (MD5)
LICENSE.txt: 4206 bytes, checksum: d218eee6aaaaae42b4c1785ce9a64d10 (MD5)
Previous issue date: 2018-04-1
Purchasing Maturity of Rijkswaterstaat Process and organization assessment of the purchasing function
No full textPurchase has been quiet a new profession field for Rijkswaterstaat (RWS), since it has introduced the ‘corporate purchasing strategy’. As it had prescribed the market in a detailed way ‘what’ to do for decades, it ‘buys’ its infrastructure assets from the market now. The need to assess this new strategic function of RWS originates from the fact that RWS lacks a tool to measure its purchasing performance. To what level has RWS professionalized its purchasing processes and activities? This question is quiet important since RWS strongly announces to become a professional and leading principal in the road infrastructure section. My research has attempted to give an impression and an initial appraisal about the current purchasing activities of RWS with a measuring model.Construction Management and EngineeringBouwCivil Engineering and Geoscience
ANÁLISE DE TENDÊNCIAS E PADRÕES EMERGENTES EM MÉTODOS DE ENSINO DE CÁLCULO: UMA ABORDAGEM BIBLIOMÉTRICA BASEADA NO VOSVIEWER
No full textThis study aims to clarify emerging trends and models in the teaching methods of Calculus by analyzing bibliographic data. The research utilizes the Scopus database in combination with analytical tools such as VOSviewer and CiteSpace, to construct a knowledge map, analyze author collaborations, and identify key research topics. The results of the analysis provide valuable insights into the development trends of Calculus teaching methods, highlight the main research topics, and examine the distribution of influence among authors in the field. These findings offer a deeper understanding of the evolution of teaching methods for Calculus, emphasizing the changes and improvements made to address the increasing learning demands of students. Based on these insights, practical recommendations are proposed to support educators, researchers, and policymakers in enhancing teaching effectiveness and developing training strategies that align with global educational trends.Este estudo visa esclarecer tendências e modelos emergentes nos métodos de ensino de Cálculo por meio da análise de dados bibliográficos. A pesquisa utiliza o banco de dados Scopus em combinação com ferramentas analíticas como VOSviewer e CiteSpace para construir um mapa de conhecimento, analisar colaborações de autores e identificar tópicos de pesquisa importantes. Os resultados da análise fornecem insights valiosos sobre as tendências de desenvolvimento dos métodos de ensino de Cálculo, destacam os principais tópicos de pesquisa e examinam a distribuição de influência entre autores no campo. Essas descobertas oferecem uma compreensão mais profunda da evolução dos métodos de ensino de Cálculo, enfatizando as mudanças e melhorias feitas para atender às crescentes demandas de aprendizagem dos alunos. Com base nesses insights, recomendações práticas são propostas para apoiar educadores, pesquisadores e formuladores de políticas no aprimoramento da eficácia do ensino e no desenvolvimento de estratégias de treinamento que se alinhem às tendências educacionais globais
Secure Communication of Electric Drive System Using Chaotic Systems Base on Disturbance Observer and Fuzzy Brain Emotional Learning Neural Network
No full textThis paper presents a novel wireless control framework for electric drive systems by employing a fuzzy brain emotional learning neural network (FBELNN) controller in conjunction with a Disturbance Observer (DO). The communication scheme uses chaotic system dynamics to ensure data confidentiality and robustness against disturbance in wireless environments. To be applied to embedded microprocessors, the continuous-time chaotic system is discretized using the Grunwald–Letnikov approximation. To avoid the loss of generality of chaotic behavior, Lyapunov exponents are computed to validate the preservation of chaos in the discrete-time domain. The FBELNN controller is then developed to synchronize two non-identical chaotic systems under different initial conditions, enabling secure data encryption and decryption. Additionally, the DOB is introduced to estimate and mitigate the effects of bounded uncertainties and external disturbances, enhancing the system’s resilience to stealthy attacks. The proposed control structure is experimentally implemented on a wireless communication system utilizing ESP32 microcontrollers (Espressif Systems, Shanghai, China) based on the ESP-NOW protocol. Both control and feedback signals of the electric drive system are encrypted using chaotic states, and real-time decryption at the receiver confirms system integrity. Experimental results verify the effectiveness of the proposed method in achieving robust synchronization, accurate signal recovery, and a reliable wireless control system. The combination of FBELNN and DOB demonstrates significant potential for real-time, low-cost, and secure applications in smart electric drive systems and industrial automation
IMPACTOS DA POLÍTICA E DA LEGISLAÇÃO FUNDIÁRIA NO DESENVOLVIMENTO SÓCIO-ECONÓMICO DO VIETNÃ
No full textThis study examines impacts of Land Policy and Land Law on Socio -economic development in the Socialist Republic of Vietnam from 1945 to present, such as, the tenure of agricultural land ownership, the State’s guidelines on land price, the policy on concentration and accumulation of agricultural land and policy on compensation for agricultural land recovery. The study also analyzes both the positive impacts and unexpected impacts of Land Policies on the Peasant Life. In the context of judicial reform in Vietnam, the issue of complete land law system has always been paid special attention by the Party and Vietnam State. The authors have combined traditional research methods of legal science such as legal analysis method, legal efficiency assessment method and legal comparison method. This study the author reviews the evolving land policy in the Socialist Republic of Vietnam, the impacts of Land Policy and Land Law on Socio - economic development in the Socialist Republic of Vietnam and pointing out inconsistencies and shortcomings. The study concludes with recommendations to improve policy and the long-term well-being of Vietnam and its people. This research may support many develop future research in Vietnam. The study of the land law become more and more urgent and very important in Vietnam.Este estudo examina os impactos da Política de Terras e da Lei de Terras no desenvolvimento socioeconómico na República Socialista do Vietnã desde 1945 para apresentar, tais como, a posse da propriedade da terra agrícola, as directrizes do Estado sobre o preço da terra, a política de concentração e acumulação de terras agrícolas e a política de compensação para a recuperação de terras agrícolas. O estudo também analisa tanto os impactos positivos como os impactos inesperados da Política de Terras na Vida Camponesa. No contexto da reforma judicial no Vietnã, a questão do sistema completo de direito fundiário tem merecido sempre uma atenção especial por parte do Partido e do Estado do Vietnã. Os autores combinaram métodos tradicionais de investigação da ciência jurídica, tais como o método de análise jurídica, o método de avaliação da eficiência jurídica e o método de comparação jurídica. Este estudo o autor analisa a evolução da política fundiária na República Socialista do Vietnã, os impactos da política fundiária e da lei de terras no desenvolvimento socioeconómico na República Socialista do Vietnã e aponta inconsistências e deficiências. O estudo conclui com recomendações para melhorar a política e o bem-estar a longo prazo do Vietnã e da sua população. Esta investigação pode apoiar muitos a desenvolver investigação futura no Vietnã. O estudo da lei de terras torna-se cada vez mais urgente e muito importante no Vietnã
A Boom Energy Regeneration System of Hybrid Hydraulic Excavator Using Energy Conversion Components
No full textIn this paper, a novel design of an energy regeneration system was proposed for recovering as well as reusing potential energy in a boom cylinder. The proposed system included a hydraulic pump/motor and an electrical motor/generator. When the boom moved down, the energy regeneration components converted the hydraulic energy to electrical energy and stored in a battery. Then, the regenerated energy was reused at subsequent cycles. In addition, an energy management strategy has been designed based on discrete time-optimal control to guarantee position tracking performance and ensure component safety during the operation. To verify the effectiveness of the proposed system, a co-simulation (using MATLAB and AMESim) was carried out. Through the simulation results, the maximum energy regeneration efficiency could achieve up to 44%. Besides, the velocity and position of the boom cylinder achieved good performance with the proposed control strategy
- …
