scholarly journals Mid-Air Drawing of Curves on 3D Surfaces in Virtual Reality

2021 ◽  
Vol 40 (3) ◽  
pp. 1-17
Author(s):  
Rahul Arora ◽  
Karan Singh
Keyword(s):  
Fundamental Problem ◽  
User Preference ◽  
Projection Algorithm ◽  
Virtual Object ◽  
Functional Design ◽  
3D Objects ◽  
Design Requirements ◽  
Surface Curve ◽  
3D Surfaces

Complex 3D curves can be created by directly drawing mid-air in immersive environments (Augmented and Virtual Realities). Drawing mid-air strokes precisely on the surface of a 3D virtual object, however, is difficult, necessitating a projection of the mid-air stroke onto the user “intended” surface curve. We present the first detailed investigation of the fundamental problem of 3D stroke projection in VR. An assessment of the design requirements of real-time drawing of curves on 3D objects in VR is followed by the definition and classification of multiple techniques for 3D stroke projection. We analyze the advantages and shortcomings of these approaches both theoretically and via practical pilot testing. We then formally evaluate the two most promising techniques spraycan and mimicry with 20 users in VR. The study shows a strong qualitative and quantitative user preference for our novel stroke mimicry projection algorithm. We further illustrate the effectiveness and utility of stroke mimicry to draw complex 3D curves on surfaces for various artistic and functional design applications.

Requirements Capture for Inclusive Design Resources and Tools

Volume 3 ◽  
2004 ◽  
Author(s):  
Hua Dong ◽  
P. John Clarkson ◽  
Simeon Keates
Keyword(s):  
Unmet Needs ◽  
Fundamental Problem ◽  
Inclusive Design ◽  
Planning Stage ◽  
Product Planning ◽  
The Past ◽  
Design Resources ◽  
User Data ◽  
Design Requirements ◽  
The Impact

In the past twenty years, a number of resources and tools to support inclusive design have been developed. However, the impact of these resources and tools on industry is not evident — few industrialists have been using them in practice. Investigations into industry have identified unmet needs, for example, the lack of appropriate user data relating to inclusive design. The fundamental problem is that few resources and tools have been developed based on rigorous requirements capture. In fact, many of them were developed only because the developers think the information could be useful. It is essential to prepare a detailed requirements list when clarifying the task at the product planning stage. This is also true for developing resources and tools for inclusive design. Requirements capture plays an important role in identifying real needs from users and developing appropriate methods of support for them. This paper starts with a survey of available resources and tools for inclusive design, and a discussion on their merits and deficiencies in respect to industry application. A number of methods are employed for the requirements capture for an inclusive design toolkit, which leads to a consistent result. An outline of the toolkit is also presented.

Identification and Classification of Fungal Colonies in Moldy Paddy Based on Computer Vision

2018 ◽  
Vol 61 (5) ◽  
pp. 1497-1504
Author(s):  
Zhenjie Wang ◽  
Ke Sun ◽  
Lihui Du ◽  
Jian Yuan ◽  
Kang Tu ◽  
...  
Keyword(s):  
Computer Vision ◽  
Discriminant Analysis ◽  
Texture Features ◽  
Fungal Species ◽  
Projection Algorithm ◽  
Support Vector ◽  
Linear Discriminant ◽  
Sequential Selection ◽  
The Individual

Abstract. In this study, computer vision was used for the identification and classification of fungi on moldy paddy. To develop a rapid and efficient method for the classification of common fungal species found in stored paddy, computer vision was used to acquire images of individual colonies of growing fungi for three consecutive days. After image processing, the color, shape, and texture features were acquired and used in a subsequent discriminant analysis. Both linear (i.e., linear discriminant analysis and partial least squares discriminant analysis) and nonlinear (i.e., random forest and support vector machine [SVM]) pattern recognition models were employed for the classification of fungal colonies, and the results were compared. The results indicate that when using all of the features for three consecutive days, the performance of the nonlinear tools was superior to that of the linear tools, especially in the case of the SVM models, which achieved an accuracy of 100% on the calibration sets and an accuracy of 93.2% to 97.6% on the prediction sets. After sequential selection of projection algorithm, ten common features were selected for building the classification models. The results showed that the SVM model achieved an overall accuracy of 95.6%, 98.3%, and 99.0% on the prediction sets on days 2, 3, and 4, respectively. This work demonstrated that computer vision with several features is suitable for the identification and classification of fungi on moldy paddy based on the form of the individual colonies at an early growth stage during paddy storage. Keywords: Classification, Computer vision, Fungal colony, Feature selection, SVM.

scholarly journals Understanding values of sanitation users: examining preferences and behaviors for sanitation systems

2021 ◽  
Author(s):  
Zakiya A. Seymour ◽  
Eugene Cloete ◽  
Margaret McCurdy ◽  
Mira Olson ◽  
Joseph Hughes
Keyword(s):  
South Africa ◽  
Paradigm Shift ◽  
User Preference ◽  
Multiple Stakeholders ◽  
Technical Design ◽  
Technology Design ◽  
Design Attributes ◽  
User Acceptability ◽  
Sanitation Systems

Abstract Sanitation policy and development has undergone a paradigm shift away from supply-driven toward behavioral-based demand-driven approaches. This shift to increase sanitation demand requires multiple stakeholders with varying degrees of interest, knowledge, and capacity. Currently, the design of appropriate sanitation technology disconnects user preference integration from sanitation technology design, resulting in fewer sanitation technologies being adopted and used. This research examines how preferences for specific attributes of appropriate sanitation technologies and implementation arrangements influence their adoption and usage. Data collected included interviews of 1,002 sanitation users living in a peri-urban area of South Africa; the surveyed respondents were asked about their existing sanitation technology, their preferences for various sanitation technology design attributes, as well as their perspectives on current and preferred sanitation implementation arrangements. The data revealed that user acceptability of appropriate sanitation technology is influenced by the adoption classification of the users. Statistically significant motives and barriers to sanitation usage showed a differentiation between users who share private sanitation from those who use communal sanitation facilities. The user acceptability of appropriate sanitation systems is dependent on the technical design attributes of sanitation. The development of utility functions detailed the significance of seven technical design attributes and determined their respective priorities.

scholarly journals Classification of Variable Foundation Properties Based on Vehicle–Pavement–Foundation Interaction Dynamics

Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6263
Author(s):  
Robin Eunju Kim
Keyword(s):  
Fundamental Problem ◽  
Interaction Model ◽  
Nonlinear Behavior ◽  
Complex Problem ◽  
Noise Model ◽  
Space Representation ◽  
Linear Discriminant ◽  
The Road ◽  
Pavement Foundation

The dynamic interaction between vehicle, roughness, and foundation is a fundamental problem in road management and also a complex problem, with their coupled and nonlinear behavior. Thus, in this study, the vehicle–pavement–foundation interaction model was formulated to incorporate the mass inertia of the vehicle, stochastic roughness, and non-uniform and deformable foundation. Herein, a quarter-car model was considered, a filtered white noise model was formulated to represent the road roughness, and a two-layered foundation was employed to simulate the road structure. To represent the non-uniform foundation, stiffness and damping coefficients were assumed to vary either in a linear or in a quadratic manner. Subsequently, an augmented state-space representation was formulated for the entire system. The time-varying equation governing the covariance of the response was solved to examine the vehicle response, subject to various foundation properties. Finally, a linear discriminant analysis method was employed for classifying the foundation types. The performance of the classifier was validated by test sets, which contained 100 cases for each foundation type. The results showed an accuracy of over 90%, indicating that the machine learning-based classification of the foundation had the potential of using vehicle responses in road managements.

scholarly journals Review of the Dynamical Aspects of Triple Systems

1977 ◽  
Vol 33 ◽  
pp. 145-150
Author(s):  
V. Szebehely
Keyword(s):  
Fundamental Problem ◽  
Stellar Dynamics ◽  
Close Approach ◽  
Type Systems ◽  
Computational Results ◽  
Transient Phenomena ◽  
Triple Systems ◽  
Families Of Periodic Orbits ◽  
Negative Total Energy

AbstractA classification of possible motions of triple systems is presented emphasizing the transient phenomena occurring in addition to the final (asymptotic) outcome and clarifying the discrepancies between the astronomical and mathematical formulations. A conjectured possible instability is described and it is shown that systems with negative total energy and low angular momentum may lead to instability and to the formation of binaries. The ejected or escaping star may have high velocity if the triple close approach preceding the escape is sufficiently close. The computational results of several systematic series of such escapes are applied to various stellar configurations.The present status of the fundamental problem of partitioning the phase-space into stable and unstable regions is reviewed and a recently developed technique, applicable to stellar dynamics is described. Recently discovered families of periodic orbits and previously established classical configurations are shown to weaken the general instability conjecture.The possible existence of triple systems in states of dissolution offer intriguing observational challenges regarding the discovery of these projected temporary trapezium type systems.

On Developing a Psychiatric Multiaxial Schema for ICD-10

1988 ◽  
Vol 152 (S1) ◽  
pp. 38-43 ◽  
Author(s):  
J. E. Mezzich
Keyword(s):  
Psychiatric Patients ◽  
International Classification Of Diseases ◽  
International Experience ◽  
International Classification ◽  
Paper Briefly ◽  
Classification Of Diseases ◽  
Icd 10 ◽  
Design Requirements ◽  
Widespread Interest

As work proceeds on the development of the Tenth Revision of the International Classification of Diseases (ICD-10) widespread interest has been expressed in the preparation of a multiaxial diagnostic schema for psychiatric patients. In consideration of this task, the present paper briefly notes pertinent international experience on multiaxial diagnosis, the discernible purposes of this approach, design requirements, and a specific multiaxial proposal.

The evolution of functional design in rudists (Hippuritacea) and its taxonomic implications

1978 ◽  
Vol 284 (1001) ◽  
pp. 305-318 ◽  
Keyword(s):  
Functional Analysis ◽  
Evolutionary Trends ◽  
Functional Design ◽  
Poor Understanding ◽  
Solid Foundation ◽  
Taxonomic Implications ◽  
Shell Geometry ◽  
Flexible Model

Poor understanding of rudist growth geometry and anatomy has hampered systematic studies of the superfamily. A flexible model that simulates the growth of rudist shells is therefore presented so that evolutionary trends in the group may be consistently analysed; this model is constructed by rotational or irrotational stacking of inclined gnomons around a contained axis. Functional analysis of shell geometry and reconstructed anatomy provides a more solid foundation for rudist systematics. The first rudists (Diceratidae) employed one or other of the spirogyrate umbones, inherited from megalodontid ancestors, as a facultatively elevating encrustation stem. Invagination of the ligament in the Caprotinidae permitted uncoiling of the shell, though this also entailed reduced gaping and therefore externalization of food entrapment, with increasing involvement of the mantle margins. Caprotinid functional design was preadapted to several new adaptive zones, which were exploited by various advanced descendant groups. Some of these groups show homeomorphic evolution and have often been assembled by earlier workers into polyphyletic ‘families’ (e.g. Caprinidae). An attempt is therefore made to establish a skeletal classification of rudists on the basis of true clades, as distinguished by careful functional analysis.

scholarly journals IMPROVING PERSONALIZED QUESTIONNAIRE WITH REDUNDANCY REDUCTION FOR ADDRESSING COLD USER PROBLEM

2021 ◽  
Vol 5 (1) ◽  
pp. 457-466
Author(s):  
Umar Kabiru ◽  
Abubakar Muhammad
Keyword(s):  
Collaborative Filtering ◽  
Performance Improvement ◽  
Online Shopping ◽  
Cold Start ◽  
Reduction Technique ◽  
User Preference ◽  
Redundancy Reduction ◽  
Significant Performance ◽  
Filtering Techniques

User-based and item-based collaborative filtering techniques are among most explored strategies of making products’ recommendations to Users on online shopping platforms. However, a notable weakness of the collaborative filtering techniques is the cold start problem. Which include cold user problem, cold item problem and cold system problem – i.e., the failure of collaborative filtering to make recommendation of products to a new user, failure of an item to be recommended, or combination of the two respectively.  Literature investigation has shown that cold user problem could be effectively addressed using technique of personalized questionnaire. Unfortunately, where the products’ database is too large (as in Amazon.com), results obtained from personalized questionnaire technique could contain some user preference uncertainties. This paper presents technique of improving personalized questionnaire with uncertainty reduction technique. In addition, the paper presents classification of product recommendation systems. In this work we will be limited to user-based cold start.  Experimentation was conducted using Movielens dataset, where the proposed technique achieved significant performance improvement over personalized questionnaire technique with RMSE, Precision, Recall,1 and NDCG of 0.200, 0.227, 0.261, 0.174 and 0.249

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