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Low Power Full Adder Design Using PTM Transistor Model

Abstract

At present the processing power of the digital electronic chip is enormous and that has been possible because of the continuous improvement of the design methodology and fabrication technology. So, the data processing capability of the chip is increased significantly. Data processing in the electronic chip means the arithmetic operation on that data. For that reason, ALU is present in any processor. Full adder is one of the critical components of arithmetic unit. Improvement of the full adder is necessary for improving the computational performance of a chip. In order to design an efficient full adder, designer should choose an appropriate logic style. In this research, two new model of full-adder circuits are designed and analyzed using Pass Transistor logic in order to reduce power consumption and increase operational speed. The first proposed adder consists of 8 transistors and the second one consists of 10 transistors. LTSPICE is employed for simulating the proposed circuits using16nm low power high-k strained silicon transistor model. The overall performance of the proposed adder circuits and comparative results demonstrate the superiority of the proposed model.

Open access
Main Requirements of a Cyber Physical Production System Demonstrator

Abstract

The paper is focused on identifying the main requirements for developing a CPPS demonstrator prototype. This research aims to categorize the main components and interactions within a new manufacturing system which are required to accommodate a CPPS. The proposed CPPS demonstrator also includes the preliminary requirements identified from the discussions with the regional industry, so that the prototype of the production system could be easily understood and also be the basis for further collaborations. The identified requirements were structured according to the top-down principle focusing on accomplishing the major objectives to be achieved through the prototype of the production system but also on the detailed concepts of the product and the production stations, thus preparing the choice for a concrete technical solution.

Open access
Material Balance for Stepwise Extraction of Freshwater Algae Biomass with Heavy Metal Sequestration

Abstract

During our studies concerning the isolation of sulfated polysaccharides (SPs) from freshwater algae species widespread in Poland, an improved overall extraction methodology has been developed. This new, multi-step procedure allows for obtainment of several fractions that could find use in cosmetic and food industries, with the final one containing the valuable SPs, important both from economic and scientific perspective. Moreover, the process allows for easy use of typical chelating agents to remove harmful heavy metal ions without important losses in natural compounds of interest. Furthermore, a material balance has been established for said process, allowing for its easier implementation on bigger scales, and highlighting the areas which could still be improved to positively affect the final time-cost ratio of the methodology. Combined with previously published information concerning the detailed composition of obtained fractions, we aim to provide a robust and informative outlook on the potential of native freshwater algae species as cheap, raw and easily purifiable resource, usable in a number of important industries. According to the mass balance, nearly 5 % of dry mass of Cladophora glomerata is extractable with ethanol and this fraction consists mostly of fatty acids, phenolics and pigments. Another 5 % of mass can be isolated as pure SPs from aqueous fraction. Additionally, calcium from natural incrustations on the surface of C. glomerata amounts to 17 % of dry material weight and can be reclaimed from acidic wash by simple precipitation; such calcium salts have garnered significant interest as nutritional supplements.

Open access
Measurement of Maximum Deviation from Roundness Based on the Inverse Kinematics Principle

Abstract

The article deals with a special method of measuring the maximum deviation of objects from roundness based on the inverse kinematics principle. The inverse measurement mechanism is based on the immobility of the measuring probes and the object performing all the motions required to measure a dimension. The advantage of this principle is minimization of the temperature change, while the adverse effect in the measurement system is greatly reduced at the same time. The measurement methodology requires a special software evaluation of the data measured. The aim of the given measurement methodology was to establish the maximum roundness deviation that corresponds to the Least Squares Circle (LSC) method. An experiment with three measuring probes was conducted to verify the methodology.

Open access
Measurements of Galvanic Skin Response on Subjects Affected by Stress

Abstract

The aim of the present paper is to study the Galvanic Skin Response (GSR) level on subjects affected by stress. The device that we have used, connects to the people by finger electrodes to record GSR. The purpose was to find statistical differences between the activities (mental task, walking, sitting and to fill out a survey about their lives) and their stress level. During the experiment, it was found that the survey caused the source of high stress and increasing skin conductance was caused by sweat secretion (mental, physical activity). Is needed to work of collecting data from more subjects because GSR is depended on human behaviour, is variable upon many factors (their eating habits, their emotional state, their gender, their relationship with family, etc) and we need to build a substantial data set for a valid research.

Open access
Measuring the Moment and the Magnitude of the Abrupt Change of the Gaussian Process Bandwidth

Abstract

The maximum likelihood algorithm is introduced for measuring the unknown moment of abrupt change and bandwidth jump of a fast-fluctuating Gaussian random process. This algorithm can be technically implemented much simpler than the ones obtained by means of common approaches. The technique for calculating the characteristics of the synthesized measurer is presented and the closed analytical expressions for the conditional biases and variances of the resulting estimates are found using the additive local Markov approximation of the decision statistics. By statistical simulation methods, it is confirmed that the presented measurer is operable, while the theoretical formulas describing its performance well approximate the corresponding experimental data in a wide range of the parameter values of the analyzed random process.

Open access
Mechanical Properties of Aluminium Bracket Strengthening

Abstract

The aim of the research is laboratory investigation of aluminium brackets employed to fasten lightweight curtain walls to building facilities. Tensile loads perpendicular to end plates (vertical) were applied here. The author focused on the solutions intended to increase the load-carrying capacity of aluminium brackets applying the plain washer form A (DIN 125; ISO 7089), plain washer with an outer diameter about 3d (DIN 9021; ISO 7093) and additional cover plates (straps) in the location of bolt anchoring on the base plate. The aluminium brackets were tested on a steel base and concrete substrate. The flexibility of anchoring strongly affects the increase of the end plate middle point displacement and movable crosshead displacement.

Open access
Methods of Academic Education in the Field Occupational Safety and Health - Analysis of Applied Solutions in the Opinion of Students, Employees and Employers

Abstract

Methods of education applied at universities have a direct impact on matching of knowledge, skills, but also on the approach to the professional sphere of graduates, in relation to the needs and requirements of employers. It is particularly important in the case of Occupational Safety and Health field of study. Using the available means of technical and informational support of education, one should concentrate on shaping individual thinking. In times of rapid technological development, it is not the duplication that counts, but the creative thinking that must be accompanied by the ability to work in a group. And in this direction, according to the author, academic education should pursue. In the publication, the author analyses the applied methods of education. For this purpose, the results of the study of the participant’s observation, direct interviews with employees and employers, as well as the results of a survey conducted among students of the Czestochowa University of Technology, will be used. The analysis will be carried out in terms of the evaluation of applied methods of education - quality, usefulness, adjustment to expectations (students and employers), attractiveness of form and content.

Open access
Minimum Value Approach for Modelling of the Buckling Resistance of Welded I-Section High Strength Steel Columns

Abstract

The paper deals with determination of flexural resistance buckling curves for welded I-section steel members made of high strength steel (S 690). In the paper the previously proposed BF analytical model is used for approximation of FEM results obtained using moderately large deformation shell theory and ABAQUS/Standard software. Final formulation of flexural resistance buckling curves is possible through the use of the Merchant-Rankine-Murzewski approach adopted extensively in the authors’ previous papers. For nonlinear optimization, which is needed for analytical model parameters determination, the Wolfram Mathematica package is used. Obtained results for S 690 steel are presented against the results for S 355 steel.

Open access
Model of Construction Subcontractors Selection with Time Windows for their Availability

Abstract

Most construction projects involve subcontracting some work packages. A subcontractor is employed on the basis of their bid as well as according to their availability. A viable schedule must account for resource availability constraints. These resources (e.g. crews, subcontractors) engage in many projects, so they become at the disposal for a new project only in certain periods. One of the key tasks of a planner is thus synchronizing the work of resources between concurrent projects. The paper presents a mathematical model of the problem of selecting subcontractors or general contractor’s crews for a time-constrained project that accounts for the availability of contractors, as well as for the cost of subcontracting works. The proposed mixed integer-binary linear programming model enables the user to perform the time/cost trade-off analysis.

Open access