Fatih Başçiftçi

Simplification of Single-Output Boolean Functions by Exact Direct Cover Algorithm Based on Cube Algebra

Due to the nature of the exact two-level Boolean functions minimization methods most of practical applications rely on heuristic ones that are generally realized by a three step cyclic algorithm. First, the algorithm selects an On-minterm and it generates the set of prime implicants for this On-minterm; second, it determinates the essential prime implicant from among the generated prime implicants; and third, it performs a covering operation. The goal of this study, if the determination of the essential prime implicant is impossible, postponed the selection of essential prime implicant for this On-minterm and save it for a status word. When a new essential prime implicant determined, retrieve the status word. The proposed minimization algorithm is tested on several different kinds of problems and on standard MCNC benchmarks results of which are compared with ESPRESSO. The results show that proposed algorithm obtains exact results and faster than ESPRESSO.

An Off-Cubes Expanding Approach to the Problem of Separate Determination of the Essential Prime Implicants of the Single-Output Boolean Functions

The goal of this study is the avoidance of excessive amount of temporary results produced during the minimization process of the two-level single-output Boolean functions of many variables. In this paper we have proposed an off-set based-direct cover minimization method that uses a single on-cube oriented expanding of the off-cubes on which the essential prime implicants are identified in a one by one manner and are used for iterative covering the function being minimized. The amount of temporary results produced by this method does not exceed the size of the offset. The proposed algorithm is up to 3 times faster and uses significantly less amount of memory than well known ESPRESSO.

Reduced-rule based expert system by the simplification of logic functions for the diagnosis of diabetes

Diabetes is a chronic and complex endocrine disease with metabolic disorders caused by the imbalance between secreted and needed insulin levels. In the present study, all probabilities were examined considering ten (10) indications (2¹⁰=1024 different cases) of diabetes using medical expert system (MES), and accordingly, a truth table was established. This table was simplified by the simplification method of logic functions. 15 main rules were obtained using minimization method for Boolean Functions (BFs). These rules established rules base of ES. Subsequently, the parameters of 768 patients were compared with this ES. Accuracy rate of the estimations of MES, created as a result these comparisons, was determined as 97.13% in diabetes patients, 97% in non-diabetes patients, 96.5% in Type 1 patients, 98.26% in Type 2 patients and 97.44% in pregnant patients.

An interactive and multi-functional refreshable Braille device for the visually impaired

Abstract Although visually impaired people are generally considered to be dependent and helpless people, they actually share the same characteristics as other people. Thanks to the Braille alphabet, which has been developed to reduce inequality of opportunity to minimum, their lives become a little bit easier. Besides Braille alphabet, there are many devices and software developed for visually impaired people. In this study, a readable, vocalized and refreshable Braille device, which can ease the lives of visually impaired people, has been developed. The results of the tests on this device with 20 visually-impaired people whose ages ranged between 5 and 15 and who do not know the Braille alphabet indicated the usability rate of this device to be 81.8%. The usability rate of the device was found to be 97.16% in the tests with 30 visually-impaired people whose ages ranged between 10 and 33 and who know the Braille alphabet. The durability test of the device indicated that Braille cells worked with 100% efficiency in the trials from 50 characters to 4000 characters. The device was superior both in terms of features and 35% cheaper compared to the ones available on the market. Besides, it was determined that USB connection transmitted data faster compared to the Bluetooth connection.

A new suggestion for an irrigation schedule with an artificial neural network

This study used artificial neural networks (ANNs) to propose a new system of irrigation ratios and time intervals. Data on soil moisture, soil type, product type and time interval were used as input parameters for the ANN and the network was trained through the Levenberg–Marquardt learning algorithm. The outputs of the model determined the water requirement of the plant and the irrigation time intervals. The aim of this study is to perform irrigation at night, to reduce water losses from evaporation and thereby promote water conservation. In addition, the study aimed to save on energy, as less irrigation would be provided compared to daytime irrigation. The system was tested in a strawberry orchard of 1000 m2 in the Serik district of Antalya, Turkey. The trial achieved a 20.46% water saving and 23.9% energy saving.

Design of Web-Based Fuzzy Input Expert System for the Analysis of Serology Laboratory Tests

In this study, it is aimed, using the Web-based Expert System with Fuzzy Input (WESFI), to convert the patients’ (users’) Serology Laboratory Tests (SLT) results to linguistic statements (low, normal, high) and analyzing those, give a feedback to the user (patient) of the potential signs of disease. The feedbacks given to the patients are the existing interpretations in the database, which were prepared by doctors before. Furthermore, the SLT terms (Brucella Coombs, Ama, P-Protein etc.) are explained in a way that the user can understand. The WESFI is published with an interface on the web environment. In order to determine the rate of the success of the WESFI, users evaluated the system answering the “How do you find the evaluation?” question. The question has been answered by 461 users. As a result it is observed that 90% of female users, 92% of male users and 91% of all users found the system useful.

Fast computation of the prime implicants by exact direct-cover algorithm based on the new partial ordering operation rule

In this study, a novel OFF-set based direct-cover Exact Minimization Algorithm (EMA) is proposed for single-output Boolean functions represented in a sum-of-products form. To obtain the complete set of prime implicants covering the given Target Minterm (ON-minterm), the proposed method uses OFF-cubes (OFF-minterms) expanded by this Target Minterm. The amount of temporary results produced by this method does not exceed the size of the OFF-set. In order to achieve the goal of this study, which is to make faster computations, logic operations were used instead of the standard operations. Expansion OFF-cubes, commutative absorption operations and intersection operations are realized by logic operations for fast computation. The proposed minimization method is tested on several classes of benchmarks and then compared with the ESPRESSO algorithm. The results show that the proposed algorithm obtains more accurate and faster results than ESPRESSO does.

A third eye with human-computer interaction for the visually impaired☆

Abstract In order to reduce dependency of the visually impaired people on others resulting from their visual impairment, an ergonomic, portable, vocalizable and refreshable Braille reader was developed. Texts from a scanned document or any text imported from a computer are transmitted to the device developed, enabling visually handicapped persons to read a text in the Braille format by using their hands. Some innovations were made in this study with a view to further reduce the size of the previously developed circuit and to lower the cost. The circuit for charging the device and the keypad for the button circuit were redesigned. A new circuit was created for the panels which enables data transfer to the Braille cells. The newly developed device has a reduced size by 57.94%, the cost of device development is cut by 40% and the weight of device has been reduced by 33.3%.

A new approach to minimize the loss of life after natural hazards by using Android operating system

Nowadays, the usage rates of smartphones are increasing rapidly. With the versatility of its features, smartphones have succeeded in attracting users. Performing this study has also affected the usage rate of smartphones every day. It is possible to determine the position with GPS (Global Positioning System) technology which is located in smartphones. In this study, smartphone location notification was used to detect the locations of the people who were under debris after the earthquake by means of the phones on them. People who cannot be reached for any reason will be immediately identified, and emergency interventions will be possible. Thus, the survival rate of the injured will be high with early intervention. In this study, it was aimed to minimize the loss of life after the earthquake and all the negativities that would be experienced in society due to this loss. The developed application has been tested in the external world, and the obtained data are given in results section.

Binary Artificial Bee Colony Algorithm to Solve Single Objective Resource Allocation Problem

Resource allocation problem (RAP) is an optimum distributing period of limited existing resources. In this problem, there can be two possible cases: the resource is allocated or not. If so, the problem is in 0-1 integer problem class of which decision variables are binary values, and binary optimization algorithms are used to find optimum solutions for these problems. In the literature, various meta-heuristic optimization methods have been proposed for solving continuous or discrete RAP. In this paper, Artificial Bee Colony (ABC) algorithm simulated foraging behavior of real honey bees is studied to optimize RAP. The algorithm is firstly developed to solve numeric optimization problems and cannot be applied to binary problems directly. It requires a modification. In this study, the ABC algorithm has become applicable to solve the RAP and is called Binary Artificial Bee Colony (BABC) algorithm. The BABC algorithm is compared with the binary particle swarm optimization algorithm (BPSO) which is applied to the problem previously. The experimental results showed that the BABC algorithm was superior and can be alternative optimization method for solving RAP.