A New Traffic Sign Recognition Technique Taking Shuffled Frog-Leaping Algorithm into Account

Everyday humans use cars to move faster, and the world is a chaotic place, and a little distraction or a mistake could be the reason for an accident and bring people great pain. An assistance system that can distinguish and detect signs on the roads and brings the driver's attention to road signs and make them aware of their meaning could be beneficial. The most important part of the Traffic Sign Recognition System is the algorithm. In this paper, a new way toward Traffic Sign Recognition algorithm taking the advantages of Color Segmentation, support vector machines, and histograms of oriented gradients on the GTSRB dataset is proposed. The unsupervised shuffled frog-leaping algorithm is employed for segmenting the images. The results show remarkable improvements by using meta-heuristic algorithms.

     

Colour and ergonomics: On the selection of a “colour of the year”

The key role of colour in ergonomics has been emphasized by a number of researchers and design professionals. Although several research studies have been published regarding the use of colour in ergonomics, there are still some areas that need to be considered. The issue of deciding a “colour of the year” is an example, which represents a new challenge for researchers in the field of ergonomics. This is of particular interest considering the fact that the nature of research on the selection of a “colour of the year” is generally based on user experience. This paper argues that ergonomics should play a more prominent role in this field to ensure better user experience and performance. This paper highlights specific areas that need further study and development.     

Irradiance‐independent camera color calibration

For a digital color camera to represent the colors in the environment accurately, it is necessary to calibrate the camera RGB outputs in terms of a colorimetric space such as the CIEXYZ or sRGB. Assuming that the camera response is a linear function of scene luminance, the main step in the calibration is to determine a transformation matrix M mapping data from linear camera RGB to XYZ. Determining M is usually done by photographing a calibrated target, often a color checker, and then performing a least‐squares regression on the difference between the camera's RGB digital counts from each color checker patch and their corresponding true XYZ values. To measure accurately the XYZ coordinates for each patch, either a completely uniform lighting field is required, which can be hard to accomplish, or a measurement of the illuminant irradiance at each patch is needed. In this article, two computational methods are presented for camera color calibration that require only that the relative spectral power distribution of the illumination be constant across the color checker, while its irradiance may vary, and yet resolve for a color correction matrix that remains unaffected by any irradiance variation that may be present. © 2013 Wiley Periodicals, Inc. Col Res Appl, 39, 540–548, 2014     

Bioreactors for heart valve tissue engineering: a review

Bioreactors have great potential in the successful development of tissue‐engineered heart valve replacements, both at the research stage and in commercial platforms. Their ability to mimick the chemical and physiological conditions of the body has allowed researchers to study in vitro cellular responses, and this has helped in the fabrication of better and more efficient tissues in vivo. Use of different bioreactors, such as, rotating, dynamic flexure, cyclic stretch and pulsatile bioreactors, in tissue engineering of heart valves has been widely investigated. However, this research is still at its early stage, and many critical issues need to be resolved to make tissue engineered heart valves sufficiently reliable for clinical applications. In the following article, after a brief introduction to the structure and role of heart valves, the efforts of tissue engineers in designing heart valves using different bioreactors is described. © 2015 Society of Chemical Industry     

From Side Chains Rattling on Picoseconds to Ensemble Simulations of Protein Folding

Simulations of biological macromolecules have evolved tremendously since the discoveries of the 1970s. The field has moved from simple simulations in vacuo on picosecond scales to milliseconds of accurate sampling of large proteins, and it has become a standard tool in biochemistry and biophysics, rather than a dedicated theoretical one. This is partly due to increasing computational power, but it would not have been possible without huge research efforts invested in new algorithms and software. Here, we illustrate some of this development, both past and future challenges, and in particular, discuss how the recent introduction of modern ensemble methods is breaking the trend of ever-longer simulations to instead focus on throughput and sampling. This has not only helped simulations become much more accurate, but it provides statistical error estimates, which are critical, as simulations are increasingly used to predict properties that have not yet been measured experimentally.     

An Examination of Tabriz Gardens in Iranian Garden Art

This study was conducted to determine the place of historic gardens in the city of Tabriz vis-a-vis Iranian garden arts. It provides information on the historic gardens of Tabriz, which are no longer in existence, for example, ‘Saheb Abad’ Garden, ‘North’ Garden, ‘Sefa’ Garden, ‘Amir Kabir’ Garden, ‘Saheb Divan’Garden and ‘Fath Abad’ Garden, as well as four historical maps belonging to the Qajar era in the city of Tabriz. In this research, the factors influencing the design of El-Goli Garden were studied, which can be grouped into three major categories: physical, biological and cultural. After a brief study of the above factors in the city of Tabriz and its different microclimates, the types of similarities that exist relating to Iranian garden art were determined.     

Historical Gardens at Risk of the Destruction by Visitors,Case Study of El-Goli Garden (Iran)

This study, which was conducted on the only surviving garden of the historic gardens in the city of Tabriz in Iran (i.e. the garden of El-Goli), closely examines its importance and place in the Iranian art of gardening. El-Goli garden is considered as an important place in the city by foreign and local tourists. However, in recent years, with the development of Tabriz and consequently the increased need for green space and recreational areas for citizens, this historic garden has become a public promenade and park. This paper examines the risks and threats posed by the change in land use. Since visitors are the main threats, a questionnaire was developed to identify their reasons for visiting the garden, their behaviour in the garden and how they use this historic garden. The questionnaire was completed by 100 visitors who were randomly selected. The table of frequency for each variable was prepared using SPSS software. Finally, the results show that most visitors not only are unaware of the historical value, but also come to the garden for other purposes such as recreation, leisure and use of facilities and so on. Thus, their attitudes and behaviours will pave the way for the destruction of the garden.     

Numerical investigation of grooves effects on the thermal performance of helically grooved shell and coil tube heat exchanger

Heat exchangers are integral parts of important industrial units such as petrochemicals, medicine and power plants. Due to the importance of systems energy consumption, different modifications have been applied on heat exchangers in terms of size and structure. In this study, a novel heat exchanger with helically grooved annulus shell and helically coiled tube was investigated by numerical simulation. Helically grooves with the same pitch of the helical coil tube and different depth are created on the inner and outer wall of annulus shell to improve the thermal performance of heat exchanger. In the first section, thermal performance of the shell and coil heat exchanger with the helical grooves on its outer shell wall was compared with same but without helical grooves. At the second section, helically grooves created on both outer and inner wall of the annulus shell with different groove depths. The results showed that the heat exchanger with grooves on both inner and outer shell wall has better thermal performance up to 20% compared to the heat exchanger with grooves on only outer shell wall. The highest thermal performance achieves at lower flow rates and higher groove depths whereas the pressure drop did not increase significantly.     

Application of the differential transformation method and variational iteration method to large deformation of cantilever beams under point load

Large deflection of a cantilever beam subjected to a tip-concentrated load is governed by a non-linear differential equation. Since it is hard to find exact or closed-form solutions for this non-linear problem, this paper investigates the aforementioned problem via the differential transformation method (DTM) and the variational iteration method (VIM), which are well-known approximate analytical solutions. The mathematical formulation is yielded to a non-linear two-point boundary value problem. In this study, we compare the DTM and VIM results, with those of Adomian decomposition method (ADM) and the established numerical solution obtained by the Richardson extrapolation in order to verify the accuracy of the proposed methods. As an important result, it is depicted from tabulated data that the DTM results are more accurate in comparison with those obtained by the VIM and ADM, which is one of the objectives of this article. Moreover, the effects of dimensionless end point load, ??, on the slope of any point along the arc length and the dimensionless vertical and horizontal displacements are illustrated and explained. The results reveal that these methods are very effective and convenient in predicting the solution of such problems, and it is predicted that the DTM and VIM can find a wide application in new engineering problems.     

Classroom furniture and anthropometric characteristics of Iranian high school students: Proposed dimensions based on anthropometric data

The study evaluated the potential mismatch between classroom furniture dimensions and anthropometric characteristics of 978 Iranian high school students (498 girls, 480 boys), aged 15-18 years. Nine anthropometric measurements (stature, sitting height, sitting shoulder height, popliteal height, hip breadth, elbow-seat height, buttock-popliteal length, buttock-knee length and thigh clearance) and five dimensions from the existing classroom furniture were measured and then compared together (using match criterion equations) to identify any potential mismatch between them. The results indicated a considerable mismatch between body dimensions of the students and the existing classroom furniture, with seat height (60.9%), seat width (54.7%) and desktop height (51.7%) being the furniture dimensions with a higher level of mismatch. The levels of mismatch varied between the high-school grade levels and between genders, indicating their special requirements and possible problems. The proposed dimensions of the classroom furniture more appropriate for the students were given. This additional information on students' anthropometry can be used by local furniture industries as a starting point for designing more appropriate furniture for school children, or used by schools to aid in furniture selection.