Search results for: Gordon Wang
875 Identifying Degradation Patterns of LI-Ion Batteries from Impedance Spectroscopy Using Machine Learning
Authors: Yunwei Zhang, Qiaochu Tang, Yao Zhang, Jiabin Wang, Ulrich Stimming, Alpha Lee
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Forecasting the state of health and remaining useful life of Li-ion batteries is an unsolved challenge that limits technologies such as consumer electronics and electric vehicles. Here we build an accurate battery forecasting system by combining electrochemical impedance spectroscopy (EIS) -- a real-time, non-invasive and information-rich measurement that is hitherto underused in battery diagnosis -- with Gaussian process machine learning. We collect over 20,000 EIS spectra of commercial Li-ion batteries at different states of health, states of charge and temperatures -- the largest dataset to our knowledge of its kind. Our Gaussian process model takes the entire spectrum as input, without further feature engineering, and automatically determines which spectral features predict degradation. Our model accurately predicts the remaining useful life, even without complete knowledge of past operating conditions of the battery. Our results demonstrate the value of EIS signals in battery management systems.Keywords: battery degradation, machine learning method, electrochemical impedance spectroscopy, battery diagnosis
Procedia PDF Downloads 139874 A Genetic Algorithm Based Ensemble Method with Pairwise Consensus Score on Malware Cacophonous Labels
Authors: Shih-Yu Wang, Shun-Wen Hsiao
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In the field of cybersecurity, there exists many vendors giving malware samples classified results, namely naming after the label that contains some important information which is also called AV label. Lots of researchers relay on AV labels for research. Unfortunately, AV labels are too cluttered. They do not have a fixed format and fixed naming rules because the naming results were based on each classifiers' viewpoints. A way to fix the problem is taking a majority vote. However, voting can sometimes create problems of bias. Thus, we create a novel ensemble approach which does not rely on the cacophonous naming result but depend on group identification to aggregate everyone's opinion. To achieve this purpose, we develop an scoring system called Pairwise Consensus Score (PCS) to calculate result similarity. The entire method architecture combine Genetic Algorithm and PCS to find maximum consensus in the group. Experimental results revealed that our method outperformed the majority voting by 10% in term of the score.Keywords: genetic algorithm, ensemble learning, malware family, malware labeling, AV labels
Procedia PDF Downloads 80873 Design of a Robot with a Transformable Track System in Tackling Motion Barrier
Authors: Kai-Yi Cho, Fa-Shian Chang, Lih-Tyng Hwang, Chih-Feng Liu, Jeng-Nan Lee, Shun-Min Wang, Jhu-Wei Ji
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This paper presents a ground robot which has the tracked transformative structures of the motion mechanism. The robot has a good ability to adapt to the terrain, due to the front end of the track can be deformed, it can more easily pass the more complex area, such as to climb stairs and ramp areas. Usually in the disaster area, where the terrain is generally broken and complicated, there will be many slopes, broken walls, rubble, and obstacles, then if you want the robot through this area, you need to have a good off-road performance for possible complex terrain, this robot with the transformative tracked mechanism has a strong adaptability, it can overcome the limitation of the terrains to be a good rescue robot. Also, the robot has a good flexibility in the shape of contact with the ground; that can adapt the varied terrain by the deformable track, thus able to pass the different terrains, that was verified through the experiments on a test-platform and a field test. The prototype of the robot system has been developed, and experiments are carried out to verify the validity of the proposed design.Keywords: tracked robot, rescue robot, transformation mechanism, deformable track, hull design
Procedia PDF Downloads 319872 Inverted Umbrella-type Chiral Non-coplanar Ferrimagnetic Structure in Co(NO₃)₂
Authors: O. Maximova, I. L. Danilovich, E. B. Deeva, K. Y. Bukhteev, A. A. Vorobyova, I. V. Morozov, O. S. Volkova, E. A. Zvereva, I. V. Solovyev, S. A. Nikolaev, D. Phuyal, M. Abdel-Hafiez, Y. C. Wang, J. Y. Lin, J. M. Chen, D. I. Gorbunov, K. Puzniak, B. Lake, A. N. Vasiliev
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The low-dimensional magnetic systems tend to reveal exotic spin liquid ground states or form peculiar types of long-range order. Among systems of vivid interest are those characterized by the triangular motif in two dimensions. The realization of either ordered or disordered ground state in a triangular, honeycomb, or kagome lattices is are dictated by the competition of exchange interactions, also being sensitive to anisotropy and the spin value of magnetic ions. While the low-spin Heisenberg systems may arrive at a spin liquid long-range entangled quantum state with emergent gauge structures, the high-spin Ising systems may establish the rigid non-collinear structures. This study presents the case of chiral non-coplanar inverted umbrella-type ferrimagnet formed in cobalt nitrate Co(NO₃)₂ below TKeywords: chiral magnetic structures, low dimensional magnetic systems, umbrella-type ferrimagnets, chiral non-coplanar magnetic structures
Procedia PDF Downloads 113871 Keyloggers Prevention with Time-Sensitive Obfuscation
Authors: Chien-Wei Hung, Fu-Hau Hsu, Chuan-Sheng Wang, Chia-Hao Lee
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Nowadays, the abuse of keyloggers is one of the most widespread approaches to steal sensitive information. In this paper, we propose an On-Screen Prompts Approach to Keyloggers (OSPAK) and its analysis, which is installed in public computers. OSPAK utilizes a canvas to cue users when their keystrokes are going to be logged or ignored by OSPAK. This approach can protect computers against recoding sensitive inputs, which obfuscates keyloggers with letters inserted among users' keystrokes. It adds a canvas below each password field in a webpage and consists of three parts: two background areas, a hit area and a moving foreground object. Letters at different valid time intervals are combined in accordance with their time interval orders, and valid time intervals are interleaved with invalid time intervals. It utilizes animation to visualize valid time intervals and invalid time intervals, which can be integrated in a webpage as a browser extension. We have tested it against a series of known keyloggers and also performed a study with 95 users to evaluate how easily the tool is used. Experimental results made by volunteers show that OSPAK is a simple approach.Keywords: authentication, computer security, keylogger, privacy, information leakage
Procedia PDF Downloads 111870 A Systematic Review of Street-Level Policy Entrepreneurship Strategies in Different Political Contexts
Authors: Hui Wang, Huan Zhang
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This study uses systematic review and qualitative comparative analysis methods to comprehensively inquire about the recent street-level policy entrepreneurship research, to identify the characteristics and lessons we can learn from 20 years of street-level policy entrepreneurship literature, and the relations between political contexts and street-level policy entrepreneurs’ strategies. Using data from a systematic review of street-level policy entrepreneurship literature, we identify the sub-components of different political contexts and core strategies of street-level policy entrepreneurs and estimate the configurational relations between different political settings and street-level policy entrepreneurs’ strategies. Our results show that street-level policy entrepreneurs display social acuity, define the problem, and build team strategies when policy or political streams dominate. Street-level policy entrepreneurs will use lead-by-example strategies when both policy and political streams dominate. Furthermore, street-level policy entrepreneurs will use bureaucratic strategies, even if no stream dominates in the political context.Keywords: policy entrepreneurs, qualitative comparative analysis, street-level bureaucracy, systematic review
Procedia PDF Downloads 97869 Rehabilitative Walking: The Development of a Robotic Walking Training Device Using Functional Electrical Stimulation for Treating Spinal Cord Injuries and Lower-Limb Paralysis
Authors: Chung Hyun Goh, Armin Yazdanshenas, X. Neil Dong, Yong Tai Wang
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Physical rehabilitation is a necessary step in regaining lower body function after a partial paralysis caused by a spinal cord injury or a stroke. The purpose of this paper is to present the development and optimization of a training device that accurately recreates the motions in a gait cycle with the goal of rehabilitation for individuals with incomplete spinal cord injuries or who are victims of a stroke. A functional electrical stimulator was used in conjunction with the training device to stimulate muscle groups pertaining to rehabilitative walking. The feasibility and reliability of the design are presented. To validate the design functionality, motion analyses of the knee and ankle gait paths were made using motion capture systems. Key results indicate that the robotic walking training device provides a viable mode of physical rehabilitation.Keywords: functional electrical stimulation, rehabilitative walking, robotic walking training device, spinal cord injuries
Procedia PDF Downloads 136868 CFD Simulation for Flow Behavior in Boiling Water Reactor Vessel and Upper Pool under Decommissioning Condition
Authors: Y. T. Ku, S. W. Chen, J. R. Wang, C. Shih, Y. F. Chang
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In order to respond the policy decision of non-nuclear homes, Tai Power Company (TPC) will provide the decommissioning project of Kuosheng Nuclear power plant (KSNPP) to meet the regulatory requirement in near future. In this study, the computational fluid dynamics (CFD) methodology has been employed to develop a flow prediction model for boiling water reactor (BWR) with upper pool under decommissioning stage. The model can be utilized to investigate the flow behavior as the vessel combined with upper pool and continuity cooling system. At normal operating condition, different parameters are obtained for the full fluid area, including velocity, mass flow, and mixing phenomenon in the reactor pressure vessel (RPV) and upper pool. Through the efforts of the study, an integrated simulation model will be developed for flow field analysis of decommissioning KSNPP under normal operating condition. It can be expected that a basis result for future analysis application of TPC can be provide from this study.Keywords: CFD, BWR, decommissioning, upper pool
Procedia PDF Downloads 251867 Artificial Neural Network in Predicting the Soil Response in the Discrete Element Method Simulation
Authors: Zhaofeng Li, Jun Kang Chow, Yu-Hsing Wang
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This paper attempts to bridge the soil properties and the mechanical response of soil in the discrete element method (DEM) simulation. The artificial neural network (ANN) was therefore adopted, aiming to reproduce the stress-strain-volumetric response when soil properties are given. 31 biaxial shearing tests with varying soil parameters (e.g., initial void ratio and interparticle friction coefficient) were generated using the DEM simulations. Based on these 45 sets of training data, a three-layer neural network was established which can output the entire stress-strain-volumetric curve during the shearing process from the input soil parameters. Beyond the training data, 2 additional sets of data were generated to examine the validity of the network, and the stress-strain-volumetric curves for both cases were well reproduced using this network. Overall, the ANN was found promising in predicting the soil behavior and reducing repetitive simulation work.Keywords: artificial neural network, discrete element method, soil properties, stress-strain-volumetric response
Procedia PDF Downloads 385866 Mikhail Bakhtin's Standpoint of Neo-Marxism and beyond: Bildungsroman as a Critique
Authors: Hsiao-Yung Wang
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This paper aims to elaborate the standpoint of neo-Marxism of Russian philosopher Mikhail Bakhtin by critical reading his concept of Bildungsroman; thereby, it aims to map the theoretical implication of spatial rhetoric and its time politics/emancipatory politics in late Bakhtin’s thought. First, it aims to outline the two revolving rings of spatiality in Bildungsroman, proceeding from 'recollecting the past' to 'foreseeing the future' on the basis of visuality and materialistic realism. Herein, Bakhtin has temporarily been leaving his previous research concern on polyphonic novel. Second, it aims to demonstrate that although Bakhtin has constantly emphasized the necessity of reconstructing opened future space, his insistence on 'emergence' has still generated a seemingly theoretical lacuna which needs to be filled. 'Doubled heterotopia,' as popularized by contemporary rhetorician Saindon, might be an adequate approach to articulate and present the rhetorical functions and dynamics of Bakhtin’s spatial rhetoric dialectically. Based on the research findings, this paper argues that Bakhtin indeed attempted to go beyond the deterministic model of Marxism and neo-Marxism strategically and reciprocally.Keywords: Bildungsroman, double heterotopia, emergence, Mikhail Bakhtin, neo-Marxism, spatial rhetoric, time-politics, visuality
Procedia PDF Downloads 253865 Long-Baseline Single-epoch RTK Positioning Method Based on BDS-3 and Galileo Penta-Frequency Ionosphere-Reduced Combinations
Authors: Liwei Liu, Shuguo Pan, Wang Gao
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In order to take full advantages of the BDS-3 penta-frequency signals in the long-baseline RTK positioning, a long-baseline RTK positioning method based on the BDS-3 penta-frequency ionospheric-reduced (IR) combinations is proposed. First, the low noise and weak ionospheric delay characteristics of the multi-frequency combined observations of BDS-3is analyzed. Second, the multi-frequency extra-wide-lane (EWL)/ wide-lane (WL) combinations with long-wavelengths are constructed. Third, the fixed IR EWL combinations are used to constrain the IR WL, then constrain narrow-lane (NL)ambiguityies and start multi-epoch filtering. There is no need to consider the influence of ionospheric parameters in the third step. Compared with the estimated ionospheric model, the proposed method reduces the number of parameters by half, so it is suitable for the use of multi-frequency and multi-system real-time RTK. The results using real data show that the stepwise fixed model of the IR EWL/WL/NL combinations can realize long-baseline instantaneous cimeter-level positioning.Keywords: penta-frequency, ionospheric-reduced (IR), RTK positioning, long-baseline
Procedia PDF Downloads 150864 A Sociological Exploration of How Chinese Highly Educated Women Respond to the Gender Stereotype in China
Authors: Qian Wang
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In this study, Chinese highly educated women referred to those women who are currently doing their Ph.D. studies, and those who have already had Ph.D. degrees. In ancient Chinese society, women were subordinated to men. The only gender role of women was to be a wife and a mother. With the rapid development of China, women are encouraged to pursue higher education. As a result of this, the number of highly educated women is growing very quickly. However, people, especially men, believe that highly educated women are challenging the traditional image of Chinese women. It is thus believed that highly educated women are very different with the traditional women. They are demonstrating an image of independent and confident women with promising careers. Plus, with the reinforcement of mass media, highly educated women are regarded as non-traditional women. People stigmatize them as the 'third gender' on the basis of male and female. Now, the 'third gender' has become a gender stereotype of highly educated women. In this study, 20 participants were interviewed to explore their perceptions of self and how these highly educated women respond to the stereotype. The study finds that Chinese highly educated women are facing a variety of problems and difficulties in their daily life, and they believe that one of the leading causes is the contradiction between patriarchal values and the views of gender equality in contemporary China. This study gives rich qualitative data in the research of Chinese women and will help to extend the current Chinese gender studies.Keywords: Chinese highly educated women, gender stereotype, self, the ‘third gender’
Procedia PDF Downloads 185863 Artificial Intelligence and Distributed System Computing: Application and Practice in Real Life
Authors: Lai Junzhe, Wang Lihao, Burra Venkata Durga Kumar
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In recent years, due to today's global technological advances, big data and artificial intelligence technologies have been widely used in various industries and fields, playing an important role in reducing costs and increasing efficiency. Among them, artificial intelligence has derived another branch in its own continuous progress and the continuous development of computer personnel, namely distributed artificial intelligence computing systems. Distributed AI is a method for solving complex learning, decision-making, and planning problems, characterized by the ability to take advantage of large-scale computation and the spatial distribution of resources, and accordingly, it can handle problems with large data sets. Nowadays, distributed AI is widely used in military, medical, and human daily life and brings great convenience and efficient operation to life. In this paper, we will discuss three areas of distributed AI computing systems in vision processing, blockchain, and smart home to introduce the performance of distributed systems and the role of AI in distributed systems.Keywords: distributed system, artificial intelligence, blockchain, IoT, visual information processing, smart home
Procedia PDF Downloads 101862 Understanding the ‘Third Gender’: A Qualitative Study of the Perception of Being a Leftover Woman among Chinese Female Ph.D. Students
Authors: Qian Wang
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In recent years, a growing number of Chinese women choose to pursue Ph.D. education. Except for the male and female, women with PhD degrees are stigmatized as the ‘third gender’ in Chinese society. People, especially most men, believe that female PhD students challenge the traditional image and gender role of Chinese women. This gender stereotype causes a range of difficulties in finding partners in marriage market for Chinese female PhD students. In this study, the author conducted in-depth interviews with 15 participants who are currently doing their PhD studies in Chinese universities to explore their perceptions of being leftover women on the basis of their experience. All the participants are single. Based on the analysis of qualitative data, this study found that the ‘leftover women’ phenomenon among Chinese female PhD students is the result of the contradictions generated between Chinese patriarchal society and them. Although Chinese female PhD students is an attention-attracting group, the studies about them are very limited in China. This study could not only contribute to the understanding of the ‘third gender’ phenomenon and the ‘leftover women’ studies in China, but also, in practical level, could give some guidance for governments to resolve the social problems of female PhD students.Keywords: Chinese female Ph.D. students, the ‘leftover women’, the Chinese patriarchal society, gender role, Chinese culture
Procedia PDF Downloads 206861 Examining the Effects of College Education on Democratic Attitudes in China: A Regression Discontinuity Analysis
Authors: Gang Wang
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Education is widely believed to be a prerequisite for democracy and civil society, but the causal link between education and outcome variables is usually hardly to be identified. This study applies a fuzzy regression discontinuity design to examine the effects of college education on democratic attitudes in the Chinese context. In the analysis treatment assignment is determined by students’ college entry years and thus naturally selected by subjects’ ages. Using a sample of Chinese college students collected in Beijing in 2009, this study finds that college education actually reduces undergraduates’ motivation for political development in China but promotes political loyalty to the authoritarian government. Further hypotheses tests explain these interesting findings from two perspectives. The first is related to the complexity of politics. As college students progress over time, they increasingly realize the complexity of political reform in China’s authoritarian regime and rather stay away from politics. The second is related to students’ career opportunities. As students are close to graduation, they are immersed with job hunting and have a reduced interest in political freedom.Keywords: china, college education, democratic attitudes, regression discontinuity
Procedia PDF Downloads 345860 The Usefulness of Financial Certification in Taiwan
Authors: Chih-Mei Wang, Jon-Chao Hong, Jian-Hong Ye, Jing-Yun Fan, Chiao-Fei Lin
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The value of a certificate is to implement the criteria for evaluating work ability. Some professional certificates may make people feel good, but they are not useful in the workplace. To address this issue, this study is based on the expectancy-value model to take financial certificates as an example to explore how participants perceived the value of obtaining certification related to their usage perception of career promotion and salary increase. A total of 339 valid samples were subjected to confirmatory factor analysis and structural equation modeling; the results showed that the number of professional certificates was not significantly correlated with career promotion, but the number of professional certificates is negatively related to salary and benefits (S&B), while career promotion and S&B were positively related to job performance. The results show that the number of professional certificates does not play a significant role in the expectancy-value model. Therefore, professional certifications related to a basic level of finance was not expected to obtain in Taiwan's financial industry, and it is important to study the usefulness of some other certificates in other competitive industry.Keywords: career promotion, certificate, compensation and benefits, goal-directed behaviors, Job performance
Procedia PDF Downloads 186859 Co-Limitation of Iron Deficiency in Stem Allantoin and Amino-N Formation of Peanut Plants Intercropped with Cassava
Authors: Hong Li, Tingxian Li, Xudong Wang, Weibo Yang
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Co-limitation of iron (Fe) deficiency in legume nitrogen fixation process is not well understood. Our objectives were to examine how peanut plants cope with Fe deficiency with the rhizobial inoculants and N-nutrient treatments. The study was conducted in the tropical Hainan Island during 2012-2013. The soil was strongly acidic (pH 4.6±0.7) and deficient in Fe (9.2±2.3 mg/kg). Peanut plants were intercropped with cassava. The inoculants and N treatments were arranged in a split-plot design with three blocks. Peanut root nodulation, stem allantoin, amino acids and plant N derived from fixation (P) reduced with declining soil Fe concentrations. The treatment interactions were significant on relative ureide % and peanut yields (P<0.05). Residual fixed N from peanut plants was beneficial to cassava plants. It was concluded that co-variance of Fe deficiency could influence peanut N fixation efficiency and rhizobia and N inputs could help improving peanut tolerance to Fe deficiency stress.Keywords: amino acids, plant N derived from N fixation, root nodulation, soil Fe co-variance, stem ureide, peanuts, cassava
Procedia PDF Downloads 289858 The Efficacy of Contractual Governance on Task and Relationship Conflict in Construction Projects
Authors: Jingya You, Yongqiang Chen, Yuanyuan Hua, Wenqian Wang
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Conflict is commonplace in construction projects, and construction projects always involve designing contracts between the owner and the contractor. However, how the contract affects the level of conflict between the owner and the contractor has not been elaborated. The purpose of this paper is to explain the effects of contractual complexity on the level of conflict, including task conflict and relationship conflict, and then to demonstrate the moderating role played by the interdependence between the owner and the contractor. Using data from owners and general contractors in the Chinese construction industry, this research reveals that contractual control will reduce relationship conflict. Contractual coordination will also reduce relationship conflict by the mediating effect of task conflict. Besides, under high joint interdependence, the positive relationship between task conflict and relationship conflict is strengthened, while high interdependence asymmetry has effects on weakening the relationship between task conflict and relationship conflict. The findings provide guidance for contract designers to draft suitable contracts in order to effectively deal with conflict. Additionally, this research implies that project managers should highlight the importance of contract in conflict management.Keywords: construction projects, contract governance, interdependence, relationship conflict, task conflict
Procedia PDF Downloads 206857 An Automated Bender Element System Used for S-Wave Velocity Tomography during Model Pile Installation
Authors: Yuxin Wu, Yu-Shing Wang, Zitao Zhang
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A high-speed and time-lapse S-wave velocity measurement system has been built up for S-wave tomography in sand. This system is based on bender elements and applied to model pile tests in a tailor-made pressurized chamber to monitor the shear wave velocity distribution during pile installation in sand. Tactile pressure sensors are used parallel together with bender elements to monitor the stress changes during the tests. Strain gages are used to monitor the shaft resistance and toe resistance of pile. Since the shear wave velocity (Vs) is determined by the shear modulus of sand and the shaft resistance of pile is also influenced by the shear modulus of sand around the pile, the purposes of this study are to time-lapse monitor the S-wave velocity distribution change at a certain horizontal section during pile installation and to correlate the S-wave velocity distribution and shaft resistance of pile in sand.Keywords: bender element, pile, shaft resistance, shear wave velocity, tomography
Procedia PDF Downloads 418856 Vertical Urban Design Guideline and Its Application to Measure Human Cognition and Emotions
Authors: Hee Sun (Sunny) Choi, Gerhard Bruyns, Wang Zhang, Sky Cheng, Saijal Sharma
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This research addresses the need for a comprehensive framework that can guide the design and assessment of multi-level public spaces and public realms and their impact on the built environment. The study aims to understand and measure the neural mechanisms involved in this process. By doing so, it can lay the foundation for vertical and volumetric urbanism and ensure consistency and excellence in the field while also supporting scientific research methods for urban design with cognitive neuroscientists. To investigate these aspects, the paper focuses on the neighborhood scale in Hong Kong, specifically examining multi-level public spaces and quasi-public spaces within both commercial and residential complexes. The researchers use predictive Artificial Intelligence (AI) as a methodology to assess and comprehend the applicability of the urban design framework for vertical and volumetric urbanism. The findings aim to identify the factors that contribute to successful public spaces within a vertical living environment, thus introducing a new typology of public spaces.Keywords: vertical urbanism, scientific research methods, spatial cognition, urban design guideline
Procedia PDF Downloads 65855 Effect of Climate Change on the Genomics of Invasiveness of the Whitefly Bemisia tabaci Species Complex by Estimating the Effective Population Size via a Coalescent Method
Authors: Samia Elfekih, Wee Tek Tay, Karl Gordon, Paul De Barro
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Invasive species represent an increasing threat to food biosecurity, causing significant economic losses in agricultural systems. An example is the sweet potato whitefly, Bemisia tabaci, which is a complex of morphologically indistinguishable species causing average annual global damage estimated at US$2.4 billion. The Bemisia complex represents an interesting model for evolutionary studies because of their extensive distribution and potential for invasiveness and population expansion. Within this complex, two species, Middle East-Asia Minor 1 (MEAM1) and Mediterranean (MED) have invaded well beyond their home ranges whereas others, such as Indian Ocean (IO) and Australia (AUS), have not. In order to understand why some Bemisia species have become invasive, genome-wide sequence scans were used to estimate population dynamics over time and relate these to climate. The Bayesian Skyline Plot (BSP) method as implemented in BEAST was used to infer the historical effective population size. In order to overcome sampling bias, the populations were combined based on geographical origin. The datasets used for this particular analysis are genome-wide SNPs (single nucleotide polymorphisms) called separately in each of the following groups: Sub-Saharan Africa (Burkina Faso), Europe (Spain, France, Greece and Croatia), USA (Arizona), Mediterranean-Middle East (Israel, Italy), Middle East-Central Asia (Turkmenistan, Iran) and Reunion Island. The non-invasive ‘AUS’ species endemic to Australia was used as an outgroup. The main findings of this study show that the BSP for the Sub-Saharan African MED population is different from that observed in MED populations from the Mediterranean Basin, suggesting evolution under a different set of environmental conditions. For MED, the effective size of the African (Burkina Faso) population showed a rapid expansion ≈250,000-310,000 years ago (YA), preceded by a period of slower growth. The European MED populations (i.e., Spain, France, Croatia, and Greece) showed a single burst of expansion at ≈160,000-200,000 YA. The MEAM1 populations from Israel and Italy and the ones from Iran and Turkmenistan are similar as they both show the earlier expansion at ≈250,000-300,000 YA. The single IO population lacked the latter expansion but had the earlier one. This pattern is shared with the Sub-Saharan African (Burkina Faso) MED, suggesting IO also faced a similar history of environmental change, which seems plausible given their relatively close geographical distributions. In conclusion, populations within the invasive species MED and MEAM1 exhibited signatures of population expansion lacking in non-invasive species (IO and AUS) during the Pleistocene, a geological epoch marked by repeated climatic oscillations with cycles of glacial and interglacial periods. These expansions strongly suggested the potential of some Bemisia species’ genomes to affect their adaptability and invasiveness.Keywords: whitefly, RADseq, invasive species, SNP, climate change
Procedia PDF Downloads 119854 Numerical Study on Ultimate Capacity of Bi-Modulus Beam-Column
Authors: Zhiming Ye, Dejiang Wang, Huiling Zhao
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Development of the technology demands a higher-level research on the mechanical behavior of materials. Structural members made of bi-modulus materials have different elastic modulus when they are under tension and compression. The stress and strain states of the point effect on the elastic modulus and Poisson ratio of every point in the bi-modulus material body. Accompanied by the uncertainty and nonlinearity of the elastic constitutive relation is the complicated nonlinear problem of the bi-modulus members. In this paper, the small displacement and large displacement finite element method for the bi-modulus members have been proposed. Displacement nonlinearity is considered in the elastic constitutive equation. Mechanical behavior of slender bi-modulus beam-column under different boundary conditions and loading patterns has been simulated by the proposed method. The influence factors on the ultimate bearing capacity of slender beam and columns have been studied. The results show that as the ratio of tensile modulus to compressive modulus increases, the error of the simulation employing the same elastic modulus theory exceeds the engineering permissible error.Keywords: bi-modulus, ultimate capacity, beam-column, nonlinearity
Procedia PDF Downloads 399853 Fast and Scale-Adaptive Target Tracking via PCA-SIFT
Authors: Yawen Wang, Hongchang Chen, Shaomei Li, Chao Gao, Jiangpeng Zhang
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As the main challenge for target tracking is accounting for target scale change and real-time, we combine Mean-Shift and PCA-SIFT algorithm together to solve the problem. We introduce similarity comparison method to determine how the target scale changes, and taking different strategies according to different situation. For target scale getting larger will cause location error, we employ backward tracking to reduce the error. Mean-Shift algorithm has poor performance when tracking scale-changing target due to the fixed bandwidth of its kernel function. In order to overcome this problem, we introduce PCA-SIFT matching. Through key point matching between target and template, that adjusting the scale of tracking window adaptively can be achieved. Because this algorithm is sensitive to wrong match, we introduce RANSAC to reduce mismatch as far as possible. Furthermore target relocating will trigger when number of match is too small. In addition we take comprehensive consideration about target deformation and error accumulation to put forward a new template update method. Experiments on five image sequences and comparison with 6 kinds of other algorithm demonstrate favorable performance of the proposed tracking algorithm.Keywords: target tracking, PCA-SIFT, mean-shift, scale-adaptive
Procedia PDF Downloads 425852 Time-Frequency Feature Extraction Method Based on Micro-Doppler Signature of Ground Moving Targets
Authors: Ke Ren, Huiruo Shi, Linsen Li, Baoshuai Wang, Yu Zhou
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Since some discriminative features are required for ground moving targets classification, we propose a new feature extraction method based on micro-Doppler signature. Firstly, the time-frequency analysis of measured data indicates that the time-frequency spectrograms of the three kinds of ground moving targets, i.e., single walking person, two people walking and a moving wheeled vehicle, are discriminative. Then, a three-dimensional time-frequency feature vector is extracted from the time-frequency spectrograms to depict these differences. At last, a Support Vector Machine (SVM) classifier is trained with the proposed three-dimensional feature vector. The classification accuracy to categorize ground moving targets into the three kinds of the measured data is found to be over 96%, which demonstrates the good discriminative ability of the proposed micro-Doppler feature.Keywords: micro-doppler, time-frequency analysis, feature extraction, radar target classification
Procedia PDF Downloads 399851 Internal Leakage Analysis from Pd to Pc Port Direction in ECV Body Used in External Variable Type A/C Compressor
Authors: M. Iqbal Mahmud, Haeng Muk Cho, Seo Hyun Sang, Wang Wen Hai, Chang Heon Yi, Man Ik Hwang, Dae Hoon Kang
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Solenoid operated electromagnetic control valve (ECV) playing an important role for car’s air conditioning control system. ECV is used in external variable displacement swash plate type compressor and controls the entire air conditioning system by means of a pulse width modulation (PWM) input signal supplying from an external source (controller). Complete form of ECV contains number of internal features like valve body, core, valve guide, plunger, guide pin, plunger spring, bellows etc. While designing the ECV; dimensions of different internal items must meet the standard requirements as it is quite challenging. In this research paper, especially the dimensioning of ECV body and its three pressure ports through which the air/refrigerant passes are considered. Here internal leakage test analysis of ECV body is being carried out from its discharge port (Pd) to crankcase port (Pc) when the guide valve is placed inside it. The experiments have made both in ordinary and digital system using different assumptions and thereafter compare the results.Keywords: electromagnetic control valve (ECV), leakage, pressure port, valve body, valve guide
Procedia PDF Downloads 400850 Preventative Programs for At-Risk Families of Child Maltreatment: Using Home Visiting and Intergenerational Relationships
Authors: Kristina Gordon
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One in three children in the United States is a victim of a maltreatment investigation, and about one in nine children has a substantiated investigation. Home visiting is one of several preventative strategies rooted in an early childhood approach that fosters maternal, infant, and early childhood health, protection, and growth. In the United States, 88% of states report administering home visiting programs or state-designed models. The purpose of this study was to conduct a systematic review on home visiting programs in the United States focused on the prevention of child abuse and neglect. This systematic review included 17 articles which found that most of the studies reported optimistic results. Common across studies was program content related to (1) typical child development, (2) parenting education, and (3) child physical health. Although several factors common to home visiting and parenting interventions have been identified, no research has examined the common components of manualized home visiting programs to prevent child maltreatment. Child maltreatment can be addressed with home visiting programs with evidence-based components and cultural adaptations that increase prevention by assisting families in tackling the risk factors they face. An innovative approach to child maltreatment prevention is bringing together at-risk families with the aging community. This innovative approach was prompted due to existing home visitation programs only focusing on improving skillsets and providing temporary relationships. This innovative approach can provide the opportunity for families to build a relationship with an aging individual who can share their wisdom, skills, compassion, love, and guidance, to support families in their well-being and decrease child maltreatment occurrence. Families would be identified if they experience any of the risk factors, including parental substance abuse, parental mental illness, domestic violence, and poverty. Families would also be identified as at risk if they lack supportive relationships such as grandparents or relatives. Families would be referred by local agencies such as medical clinics, hospitals, schools, etc., that have interactions with families regularly. The aging community would be recruited at local housing communities and community centers. An aging individual would be identified by the elderly community when there is a need or interest in a relationship by or for the individual. Cultural considerations would be made when assessing for compatibility between the families and aging individuals. The pilot program will consist of a small group of participants to allow manageable results to evaluate the efficacy of the program. The pilot will include pre-and post-surveys to evaluate the impact of the program. From the results, data would be created to determine the efficacy as well as the sufficiency of the details of the pilot. The pilot would also be evaluated on whether families were referred to Child Protective Services during the pilot as it relates to the goal of decreasing child maltreatment. The ideal findings will display a decrease in child maltreatment and an increase in family well-being for participants.Keywords: child maltreatment, home visiting, neglect, preventative, abuse
Procedia PDF Downloads 104849 Comparison of Different Intraocular Lens Power Calculation Formulas in People With Very High Myopia
Authors: Xia Chen, Yulan Wang
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purpose: To compare the accuracy of Haigis, SRK/T, T2, Holladay 1, Hoffer Q, Barrett Universal II, Emmetropia Verifying Optical (EVO) and Kane for intraocular lens power calculation in patients with axial length (AL) ≥ 28 mm. Methods: In this retrospective single-center study, 50 eyes of 41 patients with AL ≥ 28 mm that underwent uneventful cataract surgery were enrolled. The actual postoperative refractive results were compared to the predicted refraction calculated with different formulas (Haigis, SRK/T, T2, Holladay 1, Hoffer Q, Barrett Universal II, EVO and Kane). The mean absolute prediction errors (MAE) 1 month postoperatively were compared. Results: The MAE of different formulas were as follows: Haigis (0.509), SRK/T (0.705), T2 (0.999), Holladay 1 (0.714), Hoffer Q (0.583), Barrett Universal II (0.552), EVO (0.463) and Kane (0.441). No significant difference was found among the different formulas (P = .122). The Kane and EVO formulas achieved the lowest level of mean prediction error (PE) and median absolute error (MedAE) (p < 0.05). Conclusion: The Kane and EVO formulas had a better success rate than others in predicting IOL power in high myopic eyes with AL longer than 28 mm in this study.Keywords: cataract, power calculation formulas, intraocular lens, long axial length
Procedia PDF Downloads 60848 Statically Fused Unbiased Converted Measurements Kalman Filter
Authors: Zhengkun Guo, Yanbin Li, Wenqing Wang, Bo Zou
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The statically fused converted position and doppler measurements Kalman filter (SF-CMKF) with additive debiased measurement conversion has been previously presented to combine the resulting states of converted position measurements Kalman filter (CPMKF) and converted doppler measurement Kalman filter (CDMKF) to yield the final state estimates under minimum mean squared error (MMSE) criterion. However, the exact compensation for the bias in the polar-to-cartesian and spherical-to-cartesian conversion are multiplicative and depend on the statistics of the cosine of the angle measurement errors. As a result, the consistency and performance of the SF-CMKF may be suboptimal in large-angle error situations. In this paper, the multiplicative unbiased position and Doppler measurement conversion for 2D (polar-to-cartesian) tracking are derived, and the SF-CMKF is improved to use those conversions. Monte Carlo simulations are presented to demonstrate the statistical consistency of the multiplicative unbiased conversion and the superior performance of the modified SF-CMKF (SF-UCMKF).Keywords: measurement conversion, Doppler, Kalman filter, estimation, tracking
Procedia PDF Downloads 195847 Domain Adaptive Dense Retrieval with Query Generation
Authors: Rui Yin, Haojie Wang, Xun Li
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Recently, mainstream dense retrieval methods have obtained state-of-the-art results on some datasets and tasks. However, they require large amounts of training data, which is not available in most domains. The severe performance degradation of dense retrievers on new data domains has limited the use of dense retrieval methods to only a few domains with large training datasets. In this paper, we propose an unsupervised domain-adaptive approach based on query generation. First, a generative model is used to generate relevant queries for each passage in the target corpus, and then, the generated queries are used for mining negative passages. Finally, the query-passage pairs are labeled with a cross-encoder and used to train a domain-adapted dense retriever. We also explore contrastive learning as a method for training domain-adapted dense retrievers and show that it leads to strong performance in various retrieval settings. Experiments show that our approach is more robust than previous methods in target domains that require less unlabeled data.Keywords: dense retrieval, query generation, contrastive learning, unsupervised training
Procedia PDF Downloads 89846 Improved Performance in Content-Based Image Retrieval Using Machine Learning Approach
Authors: B. Ramesh Naik, T. Venugopal
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This paper presents a novel approach which improves the high-level semantics of images based on machine learning approach. The contemporary approaches for image retrieval and object recognition includes Fourier transforms, Wavelets, SIFT and HoG. Though these descriptors helpful in a wide range of applications, they exploit zero order statistics, and this lacks high descriptiveness of image features. These descriptors usually take benefit of primitive visual features such as shape, color, texture and spatial locations to describe images. These features do not adequate to describe high-level semantics of the images. This leads to a gap in semantic content caused to unacceptable performance in image retrieval system. A novel method has been proposed referred as discriminative learning which is derived from machine learning approach that efficiently discriminates image features. The analysis and results of proposed approach were validated thoroughly on WANG and Caltech-101 Databases. The results proved that this approach is very competitive in content-based image retrieval.Keywords: CBIR, discriminative learning, region weight learning, scale invariant feature transforms
Procedia PDF Downloads 173