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Blasting is an economical method for rock breakage in open-pit mines. Backbreak is an undesirable phenomenon induced by blasting operations and has several unsuitable effects such as equipment instability and decreased performance of the blasting. Therefore, accurate estimation of backbreak is required for minimizing the environmental problems. The primary purpose of this paper is to propose a novel predictive model for estimating the backbreak at Shur River Dam region, Iran, using particle swarm optimization (PSO).

For this work, a total of 84 blasting events were considered and five effective factors on backbreak including spacing, burden, stemming, rock mass rating and specific charge were measured. To evaluate the accuracy of the proposed PSO model, multiple regression (MR) model was also developed, and the results of two predictive models were compared with actual field data.

Based on two statistical metrics [i.e. coefficient of determination (R²) and root mean square error (RMSE)], it was found that the proposed PSO model (with R² = 0.960 and RMSE = 0.08) can predict backbreak better than MR (with R² = 0.873 and RMSE = 0.14).

The analysis indicated that the specific charge is the most effective parameter on backbreak among all independent parameters used in this study.

The purpose of this paper is to propose three imperialist competitive algorithm (ICA)-based models for predicting the blast-induced ground vibrations in Shur River dam region, Iran.

For this aim, 76 data sets were used to establish the ICA-linear, ICA-power and ICA-quadratic models. For comparison aims, artificial neural network and empirical models were also developed. Burden to spacing ratio, distance between shot points and installed seismograph, stemming, powder factor and max charge per delay were used as the models’ input, and the peak particle velocity (PPV) parameter was used as the models’ output.

After modeling, the various statistical evaluation criteria such as coefficient of determination (R2) were applied to choose the most precise model in predicting the PPV. The results indicate the ICA-based models proposed in the present study were more acceptable and reliable than the artificial neural network and empirical models. Moreover, ICA linear model with the R2 of 0.939 was the most precise model for predicting the PPV in the present study.

In the present paper, the authors have proposed three novel prediction methods based on ICA to predict the PPV. In the next step, we compared the performance of the proposed ICA-based models with the artificial neural network and empirical models. The results indicated that the ICA-based models proposed in the present paper were superior in terms of high accuracy and have the capacity to generalize.

Outlines some basic forms of dynamic loading which cause vibrational problems in structures. Presents information on the possibility of structural damage occurring from vibration. Discusses the human response in terms of its often being the limiting factor in terms of amplitude which can be tolerated within a structure. Details industrial vibrational problems, covering areas of traffic, piling, forced vibration and industrial plant.

This study aims to propose a national frame of reference for the accreditation of engineering programs (EPs) in Tunisia. It uses as a benchmark the structure used by the world’s leading accreditation systems such as the Accreditation Board for Engineering and Technology (ABET) and Commission des Titres d’Ingénieur. It provides a comprehensive framework for academic institutions to evaluate the performance of their programs. In addition, it suggests the procedures, steps and timeline for the application process and defines the required documents that should be submitted.

The study analyzes the standards applied by well-established accreditation agencies such as ABET, Commission Titre Ingenieur and European Accredited Engineer, studies the perceptions of academicians who participated in six workshops and uses the results of surveys and interviews to characterize their opinions about accreditation. A sample population of 146 faculty members, experts and policymakers from 23 different higher education institutions in Tunisia, who had participated in the workshops mentioned above, was solicited to participate in the survey. The opinions of 51 respondents who responded to the survey were analyzed. This methodology led to the establishment of a proposed national frame of reference for accreditation of EPs.

Analysis reveals that the Ministry of Higher Education and Scientific Research (MHESR) provides authorization (“habilitation”) to institutions allowing them to offer their educational program. However, it is inaccurate to consider this procedure as accreditation because it is more of a licensure process. In addition, the MHESR grants the “habilitation” to those institutions that successfully apply. The National Authority for Assessment, quality assurance and accreditation Instance Nationale de l’Evaluation, de l’Assurance Qualité et de l’Accréditation (IEAQA) is not involved in this process, which makes the latter’s role trivial.

This frame of reference will help the MHESR to evaluate the EPs based on a comprehensive analysis of well-established accreditation systems, to improve its “habilitation” process by splitting it into two parts as per international practice, namely, licensure and accreditation and to make the existence and role of the IEAQA much clearer.

This study is the foremost study to propose a comprehensive frame of reference for accrediting EPs in Tunisia.

The purpose of this paper is to extract the angle information of direct P wave within multidimensional vibration signals obtained through the sensor array, and to realize high precision shallow burst point localization based on direct of angle (DOA).

This paper presents a method which combines adaptive covariance matrix (ACM) algorithm with geometric constraint conditions for extracting the angle information of direct P wave by using its polarization characteristics. First, modify the obtained three-dimensional vibration data by using attitude rotation matrix and unify the coordinate system of vibration field. Next, construct the beam model of direct P wave by making use of ACM algorithm and extract its angle information. Finally, modify P wave beam model by taking advantage of the space geometric constraint relations between nodes.

The results of numerical simulation show that this method not only can extract the angle information of direct P wave arriving at each node effectively, but also can evaluate the quality of extracted angle information of direct P wave. Meanwhile, the results of underground shallow explosion experiment show that this method can extract the angle information of direct P wave of each node significantly and can realize underground shallow explosion source localization based on DOA by using this information, the location error can be limited less than 50 cm and satisfies the location requirements of shallow burst point.

This paper provides a method for various problems of underground localization based on the sensor array, such as directional demolition blasting, underground damage assessment, earth-penetrating projectile burst point positioning in weaponry industry testing plant, etc., and has definite value to engineering application in underground space positioning field.

The purpose of this paper is to propose a new method to achieve omni-directional vibration vector signal acquisition, and use this method to improve the accuracy of the underground explosion point localization.

Following an introduction, this paper describes the design principle of a sensor structure, and discusses the rationality of the spherical structure of the sensor through finite element analysis. The sensor prototype is designed according to the above method, and its performance is tested by the sensor calibration experiment. Finally, applications are also discussed.

This paper shows that the method for underground omni-directional vibration signal acquisition is reasonable and feasible. The vibration sensor, designed by this method, of which the triaxial dynamic characteristics are consistent, and the three-dimensional vibration information acquired by this sensor can achieve high-precision localization for an underground explosion point.

The paper describes a new method for omni-directional vibration vector signal acquisition. The vibration sensor is developed based on this method, which has a broad application prospect in the positioning of an underground explosion point, the evaluation of explosive power and other underground projects.

There are numerous demolition techniques available to the demolition contractor from the well‐known blasting techniques to the less known hydrodemolition techniques. It is essential for the demolition contractor to be aware of the various types of demolition techniques available in the demolition industry and to know their advantages and disadvantages. It is also equally important for the demolition contractor to have a set of criteria to follow in order to arrive at the most appropriate demolition technique to employ on projects. This paper outlines the case study of the demolition of Warren Farm Bridge over the M1 motorway in the UK. The demolition was closely followed from the planning stage until the actual execution on‐site with the co‐operation of the demolition contractors and site agents. The paper also discusses the selection criteria for demolition techniques and as a result some guidelines for selecting a demolition technique have been produced.

Conventional rock blasting promotes many negative environmental impacts including ground vibration, flying rock, air blast, and the emission of noise, dust and gases. An unconventional alternative process is the application of electrohydraulic principles. Electrohydraulic blasting is able to create a state of fracturing and rupture in the rock, almost instantly. A high current impulse generator produces the energy, without the above environmental impacts caused by conventional explosives. It is particularly suitable for application in urban areas. The paper describes laboratory experiments, theoretical analysis, consideration of the geomechanical criteria of rock failure and analysis of the electrical parameters of impulse generators related to rock fragmentation. The laboratory experiments included geomechanical and electrohydraulic tests on limestone samples from 50kg up to 150kg. The test results show satisfactory efficiency and energy losses.

The purpose of this paper is to develop a structural vibration control system by using a state observer which estimates system states using displacements measured from sensors.

Friedlander's exponential decay function is used for expressing the blast load model. A semiloof shell element is developed in order to account for piezoelectric effects. The composite plate is discretized by using the semiloof shell elements, and stiffness and mass matrices of the plate are obtained from the finite element model. In order to reduce the degrees of freedom of the finite element model, mode summation method is used with weighted modal vector including initial dominant modes in the dynamic behavior.

The structural vibrations are suppressed successfully and in an optimal way by using a state observer control system which estimates system states using displacements measured from sensors.

This paper shows, for the first time, that vibrations of a cantilevered composite plate subjected to blast loading are suppressed by the use of piezoelectric actuators. The state observer and optimal linear quadratic regulator are both used at the same time to suppress the vibrations.

The purpose of this paper is to propose a gauge for the convergence of the deterministic particle swarm optimization (PSO) algorithm to obtain an optimum upper bound for PSO algorithm and also developing a precise equation for predicting the rock fragmentation, as important aims in surface mines.

In this study, a database including 80 sets of data was collected from 80 blasting events in Shur river dam region, in Iran. The values of maximum charge per delay (W), burden (B), spacing (S), stemming (ST), powder factor (PF), rock mass rating (RMR) and D80, as a standard for evaluating the fragmentation, were measured. To check the performance of the proposed PSO models, artificial neural network was also developed. Accuracy of the developed models was evaluated using several statistical evaluation criteria, such as variance account for, R-square (R²) and root mean square error.

Finding the upper bounds for the difference between the position and the best position of particles in PSO algorithm and also developing a precise equation for predicting the rock fragmentation, as important aims in surface mines.

For the first time, the convergence of the deterministic PSO is studied in this study without using the stagnation or the weak chaotic assumption. The authors also studied application of PSO inpredicting rock fragmentation.