Sharif Digital Repository

An important challenge in smart environments is how to manipulate the smart objects. Although mobile applications are typically used for controlling a smart environment, no previous study has evaluated the users performance in manipulating smart objects under different environmental complexities. This article presents an experimental comparison between three different selection techniques 3-D, 2-D, and physical user interfaces (UIs). We evaluate these techniques across two levels of environment complexity measuring 51 participants timing data and errors. Our results indicate that the 3-D UI is superior for task completion time and error, and the 2-D UI is not a better solution than the... 

In this paper, a practical educational tool based on Java programming is described. The approach is based on using a fully interactive graphical user interface for teaching cipher algorithms. As an example, a transposition cipher is covered, where students can try different keys and observe the effect of parameters such as key length, choice of letters for the key on the ciphertext. At the same time, the process of breaking the cipher algorithm (cryptanalysis) is rendered possible by students injecting known plaintext. The developed program offers an option where it tries systematically all keys (brute force) to break the cipher. Being extendable, the platform is thought to be able to play a... 

The use of touchscreen devices become a part of people daily life. Finger is used to communicate with such devices. This paper investigated the interaction between human finger and touch screen devices. A series of experiments was performed to investigate the participants' finger functionality when they press their finger on a touch screen device. The study was concluded that the pain threshold is higher than normal pressing force but for repetitive pressing the level of pain threshold will decrease. © 2019 IEEE  

In recent years, processing the images that contain human faces has been a growing research interest because of establishment and development of automatic methods especially in security applications, compression, and perceptual user interface. In this paper, a new method has been proposed for multiple face detection and tracking in video frames. The proposed method uses skin color, edge and shape information, face detection, and dynamic movement analysis of faces for more accurate real-time multiple face detection and tracking purposes. One of the main advantages of the proposed method is its robustness against usual challenges in face tracking such as scaling, rotation, scene changes, fast... 

The recently reported UNIversal QUAsiChemical Segment Activity coefficient (UNIQUAC-SAC) model [developed by Haghtalab and Yousefi Seyf Ind. Eng. Chem. Res. 2015, 54, 8611] provides a practical thermodynamic framework to be used in VLE, LLE, and SLE calculations. The UNIQUAC-SAC model has the advantage of being independent of area (q) and volume (r) structural parameters used in the combinatorial part. While the UNIFAC or UNIFAC-DMD could not apply to the 47% (44 of 94) of the studied molecules because of the undefined groups. Here, the numbers of solvents with identified segment numbers were extended from 82 to 130 with a slight refinement to the previous values. The model parameters... 

Social robots may soon be able to play an important role in expanding communication with the deaf. Based on the literature, adaptive user interfaces lead to greater user acceptance and increased teaching efficiency compared to non-adaptive ones. In this paper, we build a robotic architecture able to simultaneously adjust a robot’s teaching parameters according to both the user’s past and present performance, adapt the content of the training, and then implement it on the RASA robot to teach sign language based on these parameters in a manner similar to a human teacher. To do this, a word to teach in sign language, repetition, speed, and emotional valence were chosen to be adaptive using a... 

In this paper we describe designing and implementation of a powerful, fast and compact simple 3D modeler (SM3D). In addition to saving cost and time (due to high processing speed), 3D objects can be created with minimum system resources by using this application. Easy learning and using are other strengths of this application. Modularity using classification and applying Dynamic-Link Library files are noted aspects that are regarded in writing the source code and this causes separation of main part and user interface, so the application can be easily expanded in the future. Ability to create primary objects and also applying advanced transformations and modifiers have been considered.... 

This paper represents new development of a previously introduced mixed shear-flexural (VM) link element, and its application in inelastic analysis of frames with reduced beam sections. The multi-surfaces concept with dissimilar yield surfaces is used in definition of link element. The yield surfaces are defined in deformation space and the element has the capability of modeling interactive axial-flexural-shear yielding. It is able to consider post yield softening behavior as well as flexibility and strength degradations. It is shown that the analysis results of the new mixed axial-shear-flexural (PVM) link have good agreement with the existing experimental and finite element results. Using... 

The aim of this paper is the design and development of a novel user interface to interact with a meta system. Our focus is rather on interacting with Ambient Intelligence as a whole, which would for example enable users to influence the overall behaviors and attributes of dynamic device compositions. We call such interfaces Meta User Interfaces. The design details of a proposed user interface as well as a cognitive walkthrough evaluation are presented in this paper  

Role Based Access Control (RBAC) model is naturally suitable to organizations where users are assigned organizational roles with well-defined privileges. Nowadays, many organizations and enterprises such as banks, insurance industry and utility companies, provide online services to their veiy large number of users. This shows that assigning users to roles is a intolerable task and maintaining user-role assignment up-to-date is costly and error-prone. Also, with the increasing number of users, RBAC may have problems in prohibiting cheat and changing roles of users. To overcome these problems, user-role assignment decision can be made based on how much we trust him/her. In this paper, we... 

Establishing hidden communication is an important subject of discussion that has gained increasing importance nowadays with the development of the Internet. One of the methods introduced for establishing hidden communication is steganography. Methods of steganography have been mostly applied on images while the major characteristic of these methods is the change in the structure and features of the images so as not to be identifiable by human users. However, on the other hand, many methods have been proposed for breaking and extracting information (steganalysis) for these methods. This paper presents a method for hiding information in images by changing the appearance of the picture instead... 

Radiographic inspection is the most appreciated technique among the other non-destructive testing methods due to producing unique finger print record as the film. Converting of radiographs to a digital format and further digital image processing is the best method of enhancing the image quality and assisting the interpreter on his evaluation. In this research, different algorithms were used for image enhancement and radiograph interpretation in MATLAB environment. A graphical user interface (GUI) was created for implementation of different algorithms. Both spatial and frequency (wavelet) domains techniques were used for image enhancement. Results showed that the defect recognition... 

Reduced Beam Section (RBS) and Slotted Beam Web (SBW) are two types of seismic resistant moment connections that were introduced after the 1994 Northridge earthquake. These connections have been tested under cyclic loading and have had acceptable performance. In this paper, a new hybrid connection is introduced that is composed of RBS and SBW and is named Slotted-Web-Reduced- Flange (SWRF). Nonlinear finite element analyses are performed on SWRF under cyclic loading. It is shown that the new connection in some cases performs better than its RBS and SBW predecessors. The effects of panel zone strength, continuity plates and slot length are also investigated  

The aim of this paper is the design and development of a novel user interface to interact with a meta system. Our focus is rather on interacting with Ambient Intelligence as a whole, which would for example enable users to influence the overall behavior and attributes of dynamic device compositions. We call such interfaces Meta User Interfaces. The design details of a proposed user interface as well as a cognitive walkthrough evaluation are presented in this paper  

The aim of this article is the requirement analysis, design, proof-of-concept implementation and user evaluation of a novel user interface that is specifically developed to support interaction with ambient intelligence systems. The focus of the user interface is rather on interacting with ambient intelligence, a meta system that comes into existence as the result of the coherent behavior and collective intelligence of interconnected smart devices and systems of a domain such as meeting rooms or smart homes. To design the user interface, we conducted an empirical user and task analysis and elaborated requirements, defining the scope of human interaction with ambient intelligence. The captured... 

Traditionally, the frequency spectrum is licensed to users by government agencies in a fixed manner where the licensee has exclusive right to access the allocated band. However, with increasing demand for the spectrum and scarcity of vacant bands, a spectrum policy reform seems inevitable. Meanwhile, recent measurements suggest the possibility of sharing spectrum among different parties subject to interference-protection constraints. In order to enable access to an unused licensed spectrum, a secondary user has to monitor licensed bands and opportunistically transmit whenever no primary signal is detected. Spectrum-sharing between a primary licensee and a group of secondary users has been...