Different Types Of Operations Research Articles

Improving the Statistical Qualities of Pseudo Random Number Generators

Pseudo random and true random sequence generators are important components in many scientific and technical fields, playing a fundamental role in the application of the Monte Carlo methods and stochastic simulation. Unfortunately, the quality of the sequences produced by these generators are not always ideal in terms of randomness for many applications. We present a new nonlinear filter design that improves the output sequences of common pseudo random generators in terms of statistical randomness. Taking inspiration from techniques employed in symmetric ciphers, it is based on four seed-dependent substitution boxes, an evolving internal state register, and the combination of different types of operations with the aim of diffusing nonrandom patterns in the input sequence. For statistical analysis we employ a custom initial battery of tests and well-regarded comprehensive packages such as TestU01 and PractRand. Analysis results show that our proposal achieves excellent randomness characteristics and can even transform nonrandom sources (such as a simple counter generator) into perfectly usable pseudo random sequences. Furthermore, performance is excellent while storage consumption is moderate, enabling its implementation in embedded or low power computational platforms.

A novel unbalanced power flow analysis in active AC-DC distribution networks considering PWM convertors and distributed generations

Recent major achievements in power electronic technologies have expedited the development and proliferation of small-scale distributed generations (DGs). AC-DC distribution network creates a novel paradigm to attain the utmost benefits through smoothing the operation of different types of DGs. However, due to the asymmetrical electrifying of single-phase loads with different consumptions, variations in output power of the small-scale DGs connected to each phase, and disparate line parameters of the network, operation under unbalanced condition is inevitable. Therefore, performing AC-DC load flow analysis considering an unbalanced condition is indispensable to estimate the system states. In this paper, a novel direct approach based on backward-forward sweep (BFS) algorithm is proposed for power flow analysis in AC-DC distribution networks that applies Clarke’s transformation to model the operation of pulse width modulation (PWM) converters at unbalanced operation condition. Different control strategies including input power control (IPC), input output power control (IOPC), and output power control (OPC) are considered in the proposed formulation. Furthermore, to investigate the impacts of DGs on AC-DC distribution networks, an effective approach based on sensitivity matrix calculation is proposed to approximately update the outputs of DGs in each iteration. To evaluate the performance of the approach and examine its efficiency, the proposed formulations are applied to a hypothetical 123-bus AC-DC test system, containing different type of DGs and power converters, and compared with a heuristic method. The simulation results verify the effectiveness and applicability of the proposed method in load flow analysis of AC-DC distribution networks in unbalanced condition.

Different Types of Operations on Neutrosophic Graphs

The fuzzy graph theory uses a substantial and important role in modelling and structuring many optimization problems. DIfferent type of uncertainties exist in most of the optimization problems in real lIfe scenarios due to indeterminate and incomplete information and it is a challenging task for the expert to design those optimization problems applying fuzzy graph. To design the incomplete, uncertainty and vagueness in graphical optimization problems, several extensions of graph theoretical ideas are proposed. The idea of neutrosophic graph plays an important role to manage the uncertainty, linked with the indeterminate and incomplete data/information of any optimization problem. In this manuscript, we present the idea of regular neutrosophic graph, strong neutrosophic graph, bipartite neutrosophic graph, regular neutrosophic graph, and regular strong neutrosophic graph. We also introduce six different operations on neutrosophic graph, viz., cartesian product, composition, join, direct product, lexicographic and strong product.

Energy from nuclear fission

The physics of nuclear fission will be briefly illustrated, from the basic mechanism behind this phenomenon to the relevant physical quantities like nuclear cross sections, neutron flux and reaction products, together with the accompanying phenomenon of neutron capture and its role in determining how the fuel transforms in a nuclear reactor. The basic concepts underlying the operation of different types of nuclear reactors will be illustrated, along with the concept of fuel cycle. The aspects of radioactive waste, fuel resources and safety will also be briefly illustrated.

ANALYSIS OF COMPLICATIONS OF SURGICAL TREATMENT IN PATIENTS WITH LUNG TUMORS

The aim of the study was to identify factors that are associated with complications after surgery for lung cancer.
 Materials and Methods. Retrospective analysis of the surgical treatment results in patients with lung cancer who were operated on in 2010-2014 at the department of thoracic surgery of the Lviv Oncological Regional Treatment and Diagnostic Center. The study included 461 patients. The data of each patient were divided into the following groups: general characteristics, tumor characteristics, treatment characteristics, and complications. The whole cohort of patients was analyzed and their separate subgroups were compared by age, type of complications, and type of surgery.
 Results and Discussion. Elderly patients have three times higher levels of postoperative dyspnea and much higher levels of cardiac arrhythmias. Pulmonary complications are more common in men, after more aggressive surgeries with longer time of operative pulmonary ventilation; increase with age. This subgroup is also characterized by longer postoperative period and a higher in-hospital mortality rate. Postoperative complications such as dyspnea, fistula of the bronchial stump, and pleural empyema, higher levels of pleural punctures, and postoperative bed-day were more common in the group of patients who underwent pneumonectomy. A higher level of postoperative pneumonia and a longer drainage period were observed in the group of other operations. It is noteworthy that the level of dyspnea in elderly patients who underwent pneumonectomy is three times higher.
 Conclusions. There are age-related features connected to the onset of postoperative complications in patients with lung tumors who have undergone surgery. Complications typical for the patients after different types of operations were found. It is established that the age of patients and the type of surgical treatment significantly change the palette of postoperative complications. An improved method for predicting complications is required.

Global right inverses for Euler type differential operators on the space of smooth functions

We study Euler type partial differential operators P(θ) admitting a continuous linear right inverse on the space of smooth functions defined on Rd. Specifically, if the canonical unit vectors {ej|j≤d} are non characteristic for P then P(θ) admits a continuous linear right inverse iff P(∂) is hyperbolic w.r.t. ej for any j≤d.

Factors Affecting the Selection of the Bariatric Surgeon-A Survey Study

There are various factors considerd by the patients in the process of selecting the hospital and the surgeon like professional sertifications. The experience of the surgeon for all types of surggeries has a great influence on the patients' preference. In some surgical procedures patients prefer gender concordant surgeons like gynecological operations. These factors have been evaluated in many studies regarding different types of operations.

Partial vs. superficial parotidectomy for surgical treatment of pleomorphic adenoma of the parotid gland

Purpose: Superficial parotidectomy is still the gold standard in surgical therapy for pleomorphic adenoma. Recently, less extensive procedures such as extracapsular dissection and before that partial parotidectomy were introduced. We analyzed the data of patients treated with either partial or superficial parotidectomyand compared recurrence rates and postoperative morbidity.
 Methods: WA retrospective analysis of all the patients with pleomorphic adenomas who were treated at the Department of Otolaryngology from 2002 to 2016 was performed. The patients’ data were analyzed for outcome measures: facial nerve deficit, margin status, Frey’s syndrome, tumor size, duration of surgery and tumor recurrence.
 Results: During this period, 186 patients with pleomorphic adenomas of the parotid gland underwent surgery, 177 of these for the first time. Nine patients were referred to us with recurrence from another institution. Among these 177 patients, 86 were treated by partial parotidectomy, 75 by superficial parotidectomy and 16 by total parotidectomy. Transient facial weakness and the duration of surgery differed significantly between the different types of operation. Frey’s syndrome and recurrence rate were not significantly different between the groups.
 Conclusions: Radical surgery could be achieved with limited removal of the parotid while the recurrence rate was the same between the groups.

The Risk Related to the Influence of Sleep Deprivation on the Reliability of Human on the Example of Pilot

Abstract The purpose of this publication is to discuss the issues related to the operator sleep deficiency, its effects and the resulting risk. The issue is discussed on the example of a pilot, as a position in which the probability of occurrence of the phenomenon is high, with consequences of its occurrence that can be very severe. Despite the fact, the authors try to present the issues in a universal way enabling reference to a wide spectrum of different types of operators. In the article, concepts such as risk and fatigue are characterized. Furthermore, short and long-term fatigue are discussed, as well as the impact of shift work on human health and reliability. The second part presents methods of fatigue monitoring useful in aviation. The summary emphasizes the need for a holistic approach to the issue of crew fatigue in the management and the need for actions before commencing with work.

Essential self-adjointness of real principal type operators

We study the essential self-adjointness for real principal type differential operators. Unlike the elliptic case, we need geometric conditions even for operators on the Euclidean space with asymptotically constant coefficients, and we prove the essential self-adjointness under the null non-trapping condition.

New concepts of inverse fuzzy mixed graphs and its application.

Fuzzy mixed graph (FMG) can be used to model some graphical intercommunication network systems if there are many directed and undirected relations between some vertices. In inverse fuzzy graph, the membership value of edges are greater than or equal to the minimum of the membership value of the corresponding vertices. In inverse fuzzy mixed graph (IFMG), directed and undirected relations exist between some vertices and it can be used to analyze many graphical problems of real life such that the membership values of edges are greater than or equal to the minimum of the membership value of the corresponding pair of vertices. In this article, the concept of IFMG is introduced first with some of its properties. Then some isomorphic properties are studied and complement of IFMG is given. Different types of operations like union, intersection, product and join between two IFMGs are defined and investigated some of their related results. An algorithm of the proposed method is executed to identify some vertices. An application is depicted using the concept IFMG to examine the order of vertices in a social network group according to communication gaps.

CIBERSECURITY ON INTERNET OF ROBOTICS THINGS: EXPERIMENTAL PLATFORM

The Internet of Robotic Things (IoRT) is a technology that looks for monitoring, operating, and maintaining the tasks of multiple robots through the cloud. However, using these robots in cyberspace has a risk and an inherent problem in cybersecurity. To analyze the implications of this technology, the objective was to design, operate and submit an IoRT system with the default configuration. The proposed methodology consisted of designing an IoRT architecture; implement three robotic platforms linked to the cloud, applying a sniffing and spoofing cyberattacks, assess the impacts, and propose solutions. The experiment used three prototypes: two servo motors, a 6-degree-of-freedom arm, and a workstation with a robot. Additionally, the tools of the experiment were a conventional computer, a Raspberry Pi microcomputer, the Robotic Operative System middleware, the Kali Linux distribution, and the ThingSpeak cloud service. The contributions of the work were three, first it was proven that four types of links are sufficient to homologate, and ensure the integrity, reliability, and availability in the operation of different types of robots. Also, it was possible the connection of these robots even though they are not designed to work on the internet through a slave-robot node link. Finally, a real list of the consequences was obtained, given the vulnerabilities and the attacks tested, as well as some recommendations.Keywords: Cybersecurity, IoRT, Industry 4.0., Common Vulnerabilities and Exposures, Cloud, ROS.

Schatten-von Neumann classes of integral operators

In this work we establish sharp kernel conditions ensuring that the corresponding integral operators belong to Schatten-von Neumann classes. The conditions are given in terms of the spectral properties of operators acting on the kernel. As applications we establish several criteria in terms of different types of differential operators and their spectral asymptotics in different settings: compact manifolds, operators on lattices, domains in Rn of finite measure, and conditions for operators on Rn given in terms of anharmonic oscillators. We also give examples in the settings of compact sub-Riemannian manifolds, contact manifolds, strictly pseudo-convex CR manifolds, and (sub-)Laplacians on compact Lie groups.

Bipolar Picture Fuzzy Graphs with Application

In this manuscript, we introduce and discuss the term bipolar picture fuzzy graphs along with some of its fundamental characteristics and applications. We also initiate the concepts of complete bipolar picture fuzzy graphs and strong bipolar picture fuzzy graphs. Firstly, we apply different types of operations to bipolar picture fuzzy graphs and then we introduce various products of bipolar picture fuzzy graphs. Several other terms such as order and size, path, neighbourhood degrees, busy values of vertices and edges of bipolar picture fuzzy graphs are also discussed. These terminologies also lay the foundations for the discussion about the regular bipolar picture fuzzy graphs. Moreover, we also discuss isomorphisms, weak and co-weak isomorphisms and automorphisms of bipolar picture fuzzy graphs. Finally, at the base of bipolar picture fuzzy graph we present the construction of a bipolar picture fuzzy acquaintanceship graph, which would be an important tool to measure the symmetry or asymmetry of acquaintanceship levels of social networks, computer networks etc.

Investigation of harbor craft activities for emission inventory calculation

ABSTRACT Total emissions from all sources need to be accurately quantified in an emission inventory in order for a basin to develop their air pollution management plan. The best approach is to measure both the real-world emissions and activity for a source; however, often only emissions are measured and activity is estimated from historical factors. This report focuses on harbor craft and presents data showing that using measured emissions and historical factors for activity will lead to inaccurate emission contributions. In this research, real-world activity data were collected from the engine control module (ECM) and from a surrogate method that relied on exhaust temperature. Measured real-world activity values from 10 harbor craft were compared with historical values found in the certification cycle. The vessels included four tugboats, three pilot boats, two police boats, and one supply vessel. The results showed the activity values used in the certification cycle did not reflect the real-world activity of the 10 harbor craft vessels. On average, real-world NOx emissions were only 46% of the NOx emissions estimated by ISO 8178-E3 weighting factor. In contrast, inclusion of significantly lower load factors leads to 31% higher in-use NOx emission factors on average. CARB/EPA load factor ranges from 0.45 to 0.51 while in-use load factor ranged from 0.14 to 0.44. From this finding, researchers are cautioned about accepting the activity values in a certification test cycle, like ISO 8178 E3, and instead should measure real world activity data. This change would improve the accuracy of the emission contribution from harbor craft to the local inventory. Implications: Real-world measurements of activity and emissions are the best way to get an accurate emission contribution to emission inventory. This paper reports on the differences between the use of the traditional certification cycle and real-world activity of harbor craft. Engine control module (ECM) and exhaust temperature data from 10 harbor crafts with different types of operation were used to compare real-world activity data to certification cycle.

Analyzing the vibration parameters of gas-cleaning units operated in coal and mining industry of Kuzbass

Some research results on analyzing parameters of vibration generated during operation of different types of gas-cleaning and aspiration systems dynamic equipment exploited at Kuzbass coal and mining enterprises are generalized in the paper. An attempt to give grounding for developing diagnostic criteria for assessing technical condition of these equipment was done. The purpose of the research is in improving the existing techniques for standardizing vibration parameters and creating an algorithm for developing unified diagnostic criteria based on diagnostic features and rules classification applied for detecting the industrial fun dynamic equipment defects. In the framework of the research a comprehensive approach to analyzing vibration was applied and the obtained results proved the effectiveness of the introduced set of diagnostic techniques for analyzing vibration parameters of industrial fans and for the development of unified criteria of evaluation and forecasting. The obtained scientific results confirm the general effectiveness of the introduced approach to analyzing vibration parameters using the developed unified criteria for diagnosing physical state of the industrial fans.

Convolutional neural nets in chemical engineering: Foundations, computations, and applications

AbstractIn this article, we review the mathematical foundations of convolutional neural nets (CNNs) with the goals of: (i) highlighting connections with techniques from statistics, signal processing, linear algebra, differential equations, and optimization, (ii) demystifying underlying computations, and (iii) identifying new types of applications. CNNs are powerful machine learning models that highlight features from grid data to make predictions (regression and classification). The grid data object can be represented as vectors (in 1D), matrices (in 2D), or tensors (in 3D or higher dimensions) and can incorporate multiple channels (thus providing high flexibility in the input data representation). CNNs highlight features from the grid data by performing convolution operations with different types of operators. The operators highlight different types of features (e.g., patterns, gradients, geometrical features) and are learned by using optimization techniques. In other words, CNNs seek to identify optimal operators that best map the input data to the output data. A common misconception is that CNNs are only capable of processing image or video data but their application scope is much wider; specifically, datasets encountered in diverse applications can be expressed as grid data. Here, we show how to apply CNNs to new types of applications such as optimal control, flow cytometry, multivariate process monitoring, and molecular simulations.

The effect of risk factors on surgical and oncological results in high-risk prostate cancer: A multicentre study of the urooncology society, Turkey.

To evaluate the effect of risk factors and selected surgical methods on operative and oncological results of patients undergoing radical prostatectomy (RP) with high-risk prostate cancer (HRPC). Retrospective analysis of patients who underwent RP for HRPC from 13 urology centres between 1990 and 2019 was performed. Groups were created according to the risk factors of D'Amico classification. Patients with one risk factor were included in group 1 where group 2 consisted of patients with two or three risk factors. A total of 1519 patients were included in this study and 1073 (70.6%) patients were assigned to group 1 and 446 (29.4%) patients to group 2. Overall (biochemical and/or clinical and/or radiological) progression rate was 12.4% in group 1 and 26.5% in group 2 (P=.001). Surgical procedure was open RP in 844 (55.6%) patients and minimally invasive RP in 675 (44.4%) patients (laparoscopic and robot-assisted RP in 230 (15.1%) and 445 (29.3%) patients, respectively). Progression rates were similar in different types of operations (P=.22). Progression rate was not significantly different in patients who either underwent pelvic lymph node dissection (PLND) or not in each respective group. RP alone is an effective treatment in the majority of patients with HRPC and PLND did not affect the progression rates after RP. According to the number of pre-operative high-risk features, as the number of risk factors increases, there is a need for additional treatment.

STABILITY OF NONLINEAR FRACTIONAL DIFFERENTIAL EQUATIONS IN THE FRAME OF ATANGANA-BALEANU OPERATOR

Theory of fractional calculus with singular and non-singular kernels is pioneering and has garnered significant interest recently. Fair amount of literature on the qualitative properties of fractional differential and integral equations involving different types of operators is available. This manuscript aims to analyze the stability of a class of nonlinear fractional differential equation in terms of Atangana-Baleanu-Caputo operator. Sufficient conditions for the existence and uniqueness of solutions are obtained by employing classical fixed point theorems and Banach contraction principle. Also adequate conditions for Hyers-Ulam stability are established. To substantiate our analytic results, an example is provided with numerical simulation.

Research on Music Multiterminal Audio Authentication Based on Wireless Network

The current music multiterminal audio authentication algorithm does not consider the mutation of music signal, which leads to poor tamper detection ability and long time of audio authentication. By analyzing the characteristics and key technologies of wireless network, a wireless multiterminal audio system is established. The short-term energy calculation method is used to consider the sudden change of music signal. The music signal is divided into note segments, and chroma features of half order notes are extracted. The robust hash value is calculated by nonuniform quantization method. The dynamic time warping algorithm is used to align the notes, and the Hamming distance between the hash values of each two corresponding notes is calculated to obtain the measurement values of error series, statistical characteristics, and time distribution characteristics. According to the measurement value, the fuzzy classification method is applied to calculate the membership degree of the signals belonging to two different types of operation, and the authentication confidence degree is obtained. The tampered area of the music signal that has not passed the authentication is detected, and the music multiterminal audio authentication is realized. Experimental results show that the proposed algorithm has good tamper detection ability and can effectively shorten the audio authentication time.