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11 – 20 of over 40000The author presents new estimates of the probability weighting functions found in rank-dependent theories of choice under risk. These estimates are unusual in two senses. First…
Abstract
The author presents new estimates of the probability weighting functions found in rank-dependent theories of choice under risk. These estimates are unusual in two senses. First, they are free of functional form assumptions about both utility and weighting functions, and they are entirely based on binary discrete choices and not on matching or valuation tasks, though they depend on assumptions concerning the nature of probabilistic choice under risk. Second, estimated weighting functions contradict widely held priors of an inverse-s shape with fixed point well in the interior of the (0,1) interval: Instead the author usually finds populations dominated by “optimists” who uniformly overweight best outcomes in risky options. The choice pairs used here mostly do not provoke similarity-based simplifications. In a third experiment, the author shows that the presence of choice pairs that provoke similarity-based computational shortcuts does indeed flatten estimated probability weighting functions.
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n recent years, public key infrastructure (PKI) has emerged as co‐existent with the increasing demand for digital security. A digital signature is created using existing public…
Abstract
n recent years, public key infrastructure (PKI) has emerged as co‐existent with the increasing demand for digital security. A digital signature is created using existing public key cryptography technology. This technology will permit commercial transactions to be carried out across insecure networks without fear of tampering or forgery. The relative strength of digital signatures relies on the access control over the individual’s private key. The private key storage, which is usually password‐protected, has long been a weak link in the security chain. In this paper, we describe a novel and feasible system – BioPKI cryptosystem – that dynamically generates private keys from users’ on‐line handwritten signatures. The BioPKI cryptosystem eliminates the need of private key storage. The system is secure, reliable, convenient and non‐invasive. In addition, it ensures non‐repudiation to be addressed on the maker of the transaction instead of the computer where the transaction occurs.
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Chengyong Zheng, Hong Li and Guokuan Li
This paper presents a novel printed circuit board (PCB) film image alignment method based on distance context of image components, which can be directly used for PCB film…
Abstract
Purpose
This paper presents a novel printed circuit board (PCB) film image alignment method based on distance context of image components, which can be directly used for PCB film inspection. PCB film inspection plays a very important role in PCB production.
Design/methodology/approach
First, image components of reference film image and inspected film image are extracted. Then, local distance context (LDC) and global distance context (GDC) are computed for each image component. Using LDC and GDC, the similarity of each pair of components between the reference film image and the inspected film image are computed, the component correspondences can be established accordingly and the parameters for aligning these two images can be eventually estimated.
Findings
LDC and GDC act as the local spatial distribution descriptor and the global relative position descriptor of the current component, and they are invariant to translation, rotating and scale. Experimental results on aligning real PCB film images against various rotations and scaling transformation show that the proposed algorithm is fast and accurate and is very suitable for PCB film inspection.
Research limitations/implications
The proposed algorithm is suitable for aligning those images that have some isolated connected components, such as the PCB film images. It is not suitable for general image alignment.
Originality/value
We put forward to use LDC and GDC as the local descriptor and global descriptor of an image component, and designed a PCB film image alignment algorithm that can overcome the shortcomings of that image alignment algorithm that was based on local feature descriptors such as Fourier descriptor.
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Asanka G. Perera, Yee Wei Law, Ali Al-Naji and Javaan Chahl
The purpose of this paper is to present a preliminary solution to address the problem of estimating human pose and trajectory by an aerial robot with a monocular camera in near…
Abstract
Purpose
The purpose of this paper is to present a preliminary solution to address the problem of estimating human pose and trajectory by an aerial robot with a monocular camera in near real time.
Design/methodology/approach
The distinguishing feature of the solution is a dynamic classifier selection architecture. Each video frame is corrected for perspective using projective transformation. Then, a silhouette is extracted as a Histogram of Oriented Gradients (HOG). The HOG is then classified using a dynamic classifier. A class is defined as a pose-viewpoint pair, and a total of 64 classes are defined to represent a forward walking and turning gait sequence. The dynamic classifier consists of a Support Vector Machine (SVM) classifier C64 that recognizes all 64 classes, and 64 SVM classifiers that recognize four classes each – these four classes are chosen based on the temporal relationship between them, dictated by the gait sequence.
Findings
The solution provides three main advantages: first, classification is efficient due to dynamic selection (4-class vs 64-class classification). Second, classification errors are confined to neighbors of the true viewpoints. This means a wrongly estimated viewpoint is at most an adjacent viewpoint of the true viewpoint, enabling fast recovery from incorrect estimations. Third, the robust temporal relationship between poses is used to resolve the left-right ambiguities of human silhouettes.
Originality/value
Experiments conducted on both fronto-parallel videos and aerial videos confirm that the solution can achieve accurate pose and trajectory estimation for these different kinds of videos. For example, the “walking on an 8-shaped path” data set (1,652 frames) can achieve the following estimation accuracies: 85 percent for viewpoints and 98.14 percent for poses.
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Kyungmin Lee, Nakju Lett Doh, Wan Kyun Chung, Seoung Kyou Lee and Sang‐Yep Nam
The paper's purpose is to propose a localization algorithm for topological maps constituted by nodes and edges in a graph form. The focus is to develop a robust localization…
Abstract
Purpose
The paper's purpose is to propose a localization algorithm for topological maps constituted by nodes and edges in a graph form. The focus is to develop a robust localization algorithm that works well even under various dynamic noises.
Design/methodology/approach
For robust localization, the authors propose an algorithm which utilizes all available data such as node information, sensor measurements at the current time step (which are used in previous algorithms) and edge information, and sensor measurements at previous time steps (which have not been considered in other papers). Also, the algorithm estimates a robot's location in a multi‐modal manner which increases its robustness.
Findings
Findings show that the proposed algorithm works well in topological maps with various dynamics which are induced by the moving objects in the map and measurement noises from cheap sensors.
Originality/value
Unlike previous approaches, the proposed algorithm has three key features: usage of edge data, inclusion of history information, and a multi‐modal based approach. By virtue of these features, the paper develops an algorithm that enables robust localization performance.
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At present, the evaluation methodology on the design innovation of the stadia is not complete. The degree of innovation of the design scheme of the stadia still cannot be…
Abstract
At present, the evaluation methodology on the design innovation of the stadia is not complete. The degree of innovation of the design scheme of the stadia still cannot be quantitatively estimated; this inability makes it difficult to guide the selection of a design scheme. To solve the problem of evaluation on the innovative design of the stadia, improve such design’s evaluation theory, and accurately direct the selection of the design scheme of the stadia, the Delphi method is used to select evaluation indexes. Moreover, analytic hierarchy process (AHP) is applied to determine the index weight in this study; based on this index weight, fuzzy comprehensive evaluation is used to establish the model of the design innovation evaluation of the stadia. The model involves the comprehensive and simple selection of indexes and the high reliability of weight selection; the model can quantitatively calculate the comprehensive index evaluation value of the design innovation of the stadia in a relatively accurate and rapid way. In this study, Hunan People’s Stadium is taken as the example for design innovation evaluation; the procedure of design innovation evaluation is introduced in detail. The design innovation evaluation value of the stadia is 2.977 through analysis; this value indicates an ordinary degree of innovation. The innovation evaluation value of the shape is 3.425; this value shows a relatively high degree of innovation. The innovation evaluation value of the structure is 2.47; this value represents a relatively low degree of innovation. The model in this study is an accurate and prompt model that can conduct a comprehensive evaluation on the design innovation of the stadia based on quantitative calculation. This model directly and comprehensively finds the advantages and disadvantages of a design scheme. Thus, it is quite suitable for the design innovation evaluation of the stadia.
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Mohamed A. Eldakroury, Niechen Chen and Matthew C. Frank
This study aims to introduce a new method for locating candidate substrates in part models and evaluating their feasibility.
Abstract
Purpose
This study aims to introduce a new method for locating candidate substrates in part models and evaluating their feasibility.
Design/methodology/approach
Slices of an STL model along candidate directions are evaluated for the fitting of regular cylindrical and rectangular stock. Next, the part model is skeletonized and tested for collision assuming deposition growth of features from the candidate substrate.
Findings
The method is successfully able to find feasible substrates and conduct collision simulation for a variety of part models.
Research limitations/implications
The algorithm is limited to cylindrical and rectangular substrates and only considers collision between the substrate and the deposition head.
Originality/value
This method represents a new approach to solving a portion of the hybrid manufacturing process planning problem.
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Che-Chih Tsao, Ho-Hsin Chang, Meng-Hao Liu, Ho-Chia Chen, Yun-Tang Hsu, Pei-Ying Lin, Yih-Lin Chou, Ying-Chieh Chao, Yun-Hui Shen, Cheng-Yi Huang, Kai-Chiang Chan and Yi-Hung Chen
The purpose of this paper is to propose and demonstrate a new additive manufacturing approach that breaks the layer-based point scanning limitations to increase fabrication speed…
Abstract
Purpose
The purpose of this paper is to propose and demonstrate a new additive manufacturing approach that breaks the layer-based point scanning limitations to increase fabrication speed, obtain better surface finish, achieve material flexibility and reduce equipment costs.
Design/methodology/approach
The freeform additive manufacturing approach conceptually views a 3D article as an assembly of freeform elements distributed spatially following a flexible 3D assembly structure, which conforms to the surface of the article and physically builds the article by sequentially forming the freeform elements by a vari-directional vari-dimensional capable material deposition mechanism. Vari-directional building along tangential directions of part surface gives surface smoothness. Vari-dimensional deposition maximizes material output to increase build rate wherever allowed and minimizes deposition sizes for resolution whenever needed.
Findings
Process steps based on geometric and data processing considerations were described. Dispensing and forming of basic vari-directional and vari-dimensional freeform elements and basic operations of joining them were developed using thermoplastics. Forming of 3D articles at build rates of 2-5 times the fused deposition modeling (FDM) rate was demonstrated and improvement over ten times was shown to be feasible. FDM compatible operations using 0.7 mm wire depositions from a variable exit-dispensing unit were demonstrated. Preliminary tests of a surface finishing process showed a result of 0.8-1.9 um Ra. Initial results of dispensing wax, tin alloy and steel were also shown.
Originality/value
This is the first time that both vari-directional and vari-dimensional material depositions are combined in a new freeform building method, which has potential impact on the FDM and other additive manufacturing methods.
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Iuri Yudi Furukita Baptista, Fabiana Carvalho, Priscilla Efraim, Paulo Túlio de Souza Silveira and Jorge Behrens
Research on cross-modal sensory interactions has shown that visual aspects of food can influence consumer's expectation and perception of taste, mouthfeel and liking. This paper…
Abstract
Purpose
Research on cross-modal sensory interactions has shown that visual aspects of food can influence consumer's expectation and perception of taste, mouthfeel and liking. This paper aims to investigate the effects of a rounded (“bouba”) and a squared (“kiki”) shape on expected and perceived sweetness, bitterness, creaminess and liking of chocolates.
Design/methodology/approach
Brazilian consumers (N = 230) divided into two groups of 115 individuals each evaluated five chocolates containing 30, 40, 50, 60 and 70% of cocoa. One of the groups evaluated all formulations in the rounded shape and the other in the squared shape. Results were analysed with mixed multivariate analysis of variance (mixed-MANOVA) between shapes, repeated-measures MANOVA between pre- and post-tasting and Pearson's correlation analysis was performed between liking ratings and sweetness, bitterness and creaminess confirmation/disconfirmation.
Findings
The study found significant effects (p < 0.05) of shape on expected and perceived creaminess but not on other attributes; of cocoa percentage (30, 40, 50, 60 and 70%) on all four attributes; and time (pre- and post-tasting) on sweetness, bitterness and liking but not creaminess. Finally, it found significant negative correlations between the creaminess difference indices and the liking ratings for the 30, 50 and 60% chocolates.
Originality/value
This study reports that consumers may expect and perceive chocolates as creamier in a rounded shape than in an angular shape and that if the expectation of creaminess is not confirmed by sensory perception, acceptability may be negatively affected.
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Ye Su, Ye Yutang, Xie Yu, Yi Maoli, Zhang Jing, Luo Ying and Du Chunlei
– This paper aims to solve the issue of target positioning in auto stiffener bonder (ASB) systems for flexible printed circuits.
Abstract
Purpose
This paper aims to solve the issue of target positioning in auto stiffener bonder (ASB) systems for flexible printed circuits.
Design/methodology/approach
The proposed approach uses Phong’s bidirectional reflectance distribution function (BRDF) model to simulate the reflection of light off a target in ASB systems to predict the current pose of the target based on image brightness, update the template, decrease the initial errors in the template and narrow down the search range.
Findings
The experimental results indicate that the proposed approach can predict the inclination angle of the target with precision, presenting angle prediction errors of less than three degrees. Furthermore, with larger inclined angles, the overall matching errors were less than 1.5 pixels. Comparisons with the unmodified matching algorithm revealed that the proposed approach resulted in 65 per cent less calculation time for the algorithm and 14 per cent higher overall work efficiency in the ASB system.
Originality/value
The edge-based perspective shape matching algorithm was modified using the Phong BRDF model and enhanced algorithm efficiency with the target pose prediction method while ensuring the precision and robustness of the system. The proposed approach has high potential value and can be expanded to recognition systems for objects with varying inclination angles and highly reflective surfaces.
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