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2017

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Articles 1681 - 1710 of 1712

Full-Text Articles in Physical Sciences and Mathematics

Canonical Involution On Double Jet Bundles, Hülya Kadioğlu Jan 2017

Canonical Involution On Double Jet Bundles, Hülya Kadioğlu

Turkish Journal of Mathematics

In this study, we generalize double tangent bundles to double jet bundles. We present a secondary vector bundle structure on a 1-jet of a vector bundle. We show that the 1-jet of a vector bundle carries two vector bundle structures, namely primary and secondary structures. We also show that the manifold charts induced by primary and secondary structures belong to the same atlas. We prove that double jet bundles can be considered as a quotient of the second order jet bundle. We show that there exists a natural involution that interchanges between primary and secondary vector bundle structures on double …

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On The Stochastic Decomposition Property Of Single Server Retrialqueuing Systems, Nawel Arrar, Natalia Djellab, Jean-Bernard Baillon Jan 2017

On The Stochastic Decomposition Property Of Single Server Retrialqueuing Systems, Nawel Arrar, Natalia Djellab, Jean-Bernard Baillon

Turkish Journal of Mathematics

The study of retrial queuing systems presents great analytical difficulties. Detailed results are available for some models, whereas for other models the obtained results revealed poor information and are cumbersome (they contain Laplace transforms, integral expressions, etc.). Therefore, in practice, they present limited performance. Often, to overcome this difficulty, we use an approach based on the stochastic decomposition property that can be possessed by the model. It offers the advantages of simplification of solving complex models. This paper deals with the stochastic decomposition property of an M$^{X}$/G/1 retrial queue with impatient customers and exponential retrial times and of an M/G/1 …

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Singular Dirac Systems In The Sobolev Space, Eki̇n Uğurlu Jan 2017

Singular Dirac Systems In The Sobolev Space, Eki̇n Uğurlu

Turkish Journal of Mathematics

In this paper we construct Weyl's theory for the singular left-definite Dirac systems. In particular, we prove that there exists at least one solution of the system of equations that lies in the Sobolev space. Moreover, we describe the behavior of the solution belonging to the Sobolev space around the singular point.

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Permutation Groups With Cyclic-Block Property And $Mnfc$-Groups, Ali̇ Osman Asar Jan 2017

Permutation Groups With Cyclic-Block Property And $Mnfc$-Groups, Ali̇ Osman Asar

Turkish Journal of Mathematics

This work continues the investigation of perfect locally finite minimal non-$FC$-groups in totally imprimitive permutation $p$-groups. At present, the class of totally imprimitive permutation $p$-groups satisfying the cyclic-block property is known to be the only class of $p$-groups having common properties with a hypothetical minimal non-$FC$-group, because a totally imprimitive permutation $p$-group satisfying the cyclic-block property cannot be generated by a subset of finite exponent and every non-$FC$-subgroup of it is transitive, which are the properties satisfied by a minimal non-$FC$-group. Here a sufficient condition is given for the nonexistence of minimal non-$FC$-groups in this class of permutation groups. In …

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On $\Lambda$-Perfect Maps, Mehrdad Namdari, Mohammad Ali Siavoshi Jan 2017

On $\Lambda$-Perfect Maps, Mehrdad Namdari, Mohammad Ali Siavoshi

Turkish Journal of Mathematics

$\lambda$-Perfect maps, a generalization of perfect maps (i.e. continuous closed maps with compact fibers) are presented. Using $P_\lambda$-spaces and the concept of $\lambda$-compactness some classical results regarding $\lambda$-perfect maps will be extended. In particular, we show that if the composition $fg$ is a $\lambda$-perfect map where $f,g$ are continuous maps with $fg$ well-defined, then $f,g$ are $\alpha$-perfect and $\beta$-perfect, respectively, on appropriate spaces, where $\alpha, \beta\leq\lambda$.

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Weather Information For Tribune, H. D. Bond, J. Slattery Jan 2017

Weather Information For Tribune, H. D. Bond, J. Slattery

Kansas Agricultural Experiment Station Research Reports

In 2016, annual precipitation of 19.97 in. was recorded, which is 2.07 in. above normal. Six months had above-normal precipitation. April (5.16 in.) was the wettest month. The largest single amount of precipitation was 1.91 in. on August 7. January, the driest month, only recorded a trace of precipitation.

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Design And Implementation Of A Modified Communication Disturbance Observer For Teleoperation Systems, Zahra Zeinaly, Amin Ramezani, Sadjaad Ozgoli Jan 2017

Design And Implementation Of A Modified Communication Disturbance Observer For Teleoperation Systems, Zahra Zeinaly, Amin Ramezani, Sadjaad Ozgoli

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a novel structure for a communication disturbance observer in teleoperation systems is proposed to achieve robust stability. A time delay compensation method based on the concept of network disturbance and a communication disturbance observer (CDOB) has been proposed in past research. Unlike model-based approaches, it works without a time delay model. Therefore, it can be implemented in teleoperation systems with unknown and time-varying delay. However, it has been observed that the system model errors and external disturbances seriously affect the steady-state characteristics. Hence, in this paper, to achieve robustness against disturbance and model uncertainty, the structure of …

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Early Detection Of Sudden Cardiac Death Using Poincaré Plots And Recurrence Plot-Based Features From Hrv Signals, Vahid Houshyarifar, Mehdi Chehel Amirani Jan 2017

Early Detection Of Sudden Cardiac Death Using Poincaré Plots And Recurrence Plot-Based Features From Hrv Signals, Vahid Houshyarifar, Mehdi Chehel Amirani

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper we present a method to predict sudden cardiac death (SCD) based on the heart rate variability (HRV) signal and recurrence plots and Poincaré plot-extracted features. This work is a challenge since it is aimed to devise a method to predict SCD 5 min before its onset. The method consists of four steps: preprocessing, feature extraction, feature reduction, and classification. In the first step, the QRS complexes are detected from the electrocardiogram signal and then the HRV signal is extracted. In the second step, the recurrence plot of the HRV signal and Poincaré plot-extracted features are obtained. Four …

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Investigation Of Secondary Cooling Design Enhancements In Thermally Limited Compact Notebooks, Muhammad Azhar Ali Khan, Eray Uzgören, Ali̇ Muhtaroğlu Jan 2017

Investigation Of Secondary Cooling Design Enhancements In Thermally Limited Compact Notebooks, Muhammad Azhar Ali Khan, Eray Uzgören, Ali̇ Muhtaroğlu

Turkish Journal of Electrical Engineering and Computer Sciences

Thermal design enhancements in a thermally limited compact notebook system are investigated in this paper. System temperature, power, and fan speed are characterized under a range of activity levels. A finite element model is developed, and validated against measurements. Design enhancements improve cooling with minimum intrusion to the existing mechanical design. A passive secondary heat pipe in the system reduces the CPU temperature by 5 $^{\circ}$C, and improves the system performance through increased CPU + Graphics and Memory Controller Hub (GMCH) thermal design power (TDP) by 6.4%. When such a secondary heat pipe is considered with an integrated off-the-shelf Peltier …

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Comparing Of Phase Shifting Method And One-Dimensional Continuous Wavelet Transform Method For Reconstruction Using Phase-Only Information, Gülhan Ustabaş Kaya, Zehra Saraç Jan 2017

Comparing Of Phase Shifting Method And One-Dimensional Continuous Wavelet Transform Method For Reconstruction Using Phase-Only Information, Gülhan Ustabaş Kaya, Zehra Saraç

Turkish Journal of Electrical Engineering and Computer Sciences

The one-dimensional continuous wavelet transform method has some advantages in hologram reconstruction, when used in the only phase, compared with the phase shifting method. This paper aims to discuss these advantages. One advantage is related to image quality. Another advantage is less power spent and saving time, because the one-dimensional continuous wavelet transform method uses only one hologram and the phase shifting method uses four holograms for recording and reconstruction processes. One final advantage is that the one-dimensional continuous wavelet transform method can also be used in real-time applications. Within the context of the ongoing optimization studies, this study will …

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Comparative Study Of Conventional Modulation Schemes In Terms Of Conducted And Radiated Emi Generated By Three-Phase Inverters, Mohamed Salem, Mahmoud Hamouda, Jaleleddine Ben Hadj Slama Jan 2017

Comparative Study Of Conventional Modulation Schemes In Terms Of Conducted And Radiated Emi Generated By Three-Phase Inverters, Mohamed Salem, Mahmoud Hamouda, Jaleleddine Ben Hadj Slama

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a comparative study is carried out between the carrier (SPWM), third harmonic injection (THIPWM), and space vector (SVPWM) modulation schemes in terms of conducted (common and differential modes) and radiated electromagnetic interference (EMI) generated by three-phase two-level voltage source inverters. For this purpose, an experimental setup of the converter feeding an induction machine is developed with the aim to measure the conducted emission propagated back into the dc source and the radiated field in the vicinity of the power conversion device. Experimental results are given and analyzed in time and frequency domains. The comparative study between the …

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Assignment As A Location-Based Service In Outsourced Databases, Ahmet Sali̇h Büyükkayhan, Taflan İmre Gündem Jan 2017

Assignment As A Location-Based Service In Outsourced Databases, Ahmet Sali̇h Büyükkayhan, Taflan İmre Gündem

Turkish Journal of Electrical Engineering and Computer Sciences

Location-based services provide opportunities to organizations for tracking and utilizing their resources. Moreover, some corporations prefer to outsource their database management services. In the literature, privacy preservation techniques in outsourced spatial databases for several query types, such as nearest neighbor, K-nearest neighbor, and proximity search, have been examined. In this paper, we present an efficient application of the capacity and coverage-constrained assignment query on outsourced spatial databases. In the proposed technique, we introduce a novel spatial transformation strategy (square spiral encoding) to achieve privacy efficiently for approximate assignment query results. To process the assignment query, we use the parallel auction …

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A Neural Network Approach To Navigation Of A Mobile Robot And Obstacle Avoidance In Dynamic And Unknown Environments, Farhad Shamsfakhr, Bahram Sadeghi Bigham Jan 2017

A Neural Network Approach To Navigation Of A Mobile Robot And Obstacle Avoidance In Dynamic And Unknown Environments, Farhad Shamsfakhr, Bahram Sadeghi Bigham

Turkish Journal of Electrical Engineering and Computer Sciences

Mobile robot navigation and obstacle avoidance in dynamic and unknown environments is one of the most challenging problems in the field of robotics. Considering that a robot must be able to interact with the surrounding environment and respond to it in real time, and given the limited sensing range, inaccurate data, and noisy sensor readings, this problem becomes even more acute. In this paper, we attempt to develop a neural network approach equipped with statistical dimension reduction techniques to perform exact and fast robot navigation, as well as obstacle avoidance in such a manner. In order to increase the speed …

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Research On Magnetic Field State Analysis Of A Nonsalient Pole Synchronous Generator, Baojun Ge, Pin Lv, Dajun Tao, Fang Xiao, Hongsen Zhao Jan 2017

Research On Magnetic Field State Analysis Of A Nonsalient Pole Synchronous Generator, Baojun Ge, Pin Lv, Dajun Tao, Fang Xiao, Hongsen Zhao

Turkish Journal of Electrical Engineering and Computer Sciences

This paper is based on the definition of minor asymmetric degree and the relative position of the magnetic field. The relative position of the magnetic field is the angle between the positive and negative sequence magnetic fields. The corresponding relationship between the nonsalient pole synchronous generator steady performance and the magnetic field state is discussed when the generator operates at minor asymmetry. To analyze this corresponding relationship, the Taylor expansion formula with Lagrange remainder and symmetrical components is adopted. We study the relationship between the armature current and the relative position of the magnetic field, deducing the armature current expressions …

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An Improved Clonal Selection Algorithm Using A Tournament Selection Operator And Its Application To Microstrip Coupler Design, Ezgi̇ Deni̇z Ülker Jan 2017

An Improved Clonal Selection Algorithm Using A Tournament Selection Operator And Its Application To Microstrip Coupler Design, Ezgi̇ Deni̇z Ülker

Turkish Journal of Electrical Engineering and Computer Sciences

The clonal selection algorithm (CLONALG) is a nature-inspired metaheuristic algorithm that has been applied to various complex optimization problems from different fields of study. Tournament selection (TS) is a selection operator that is mainly used in genetic algorithms. In this paper, a novel improved clonal selection algorithm by using the TS operator (ICSAT) is introduced. To observe the improvement, ICSAT was first tested on selected benchmark functions and then to validate its efficiency ICSAT was applied to a microstrip coupler design problem. Although showing some disadvantages that generally exist in all modified algorithms, it is observed that ICSAT has a …

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Erp: An Efficient Reactive Routing Protocol For Dense Vehicular Ad Hoc Networks, Thandapany Sivakumar, Rajendiran Manoharan Jan 2017

Erp: An Efficient Reactive Routing Protocol For Dense Vehicular Ad Hoc Networks, Thandapany Sivakumar, Rajendiran Manoharan

Turkish Journal of Electrical Engineering and Computer Sciences

A vehicular ad hoc network (VANET) is a type of mobile ad hoc network (MANET) that provides an exchange of messages between vehicles. VANETs encourage researchers to create safety and comfort applications that will lead to intelligent transport systems. Conventional ad hoc routing methods may cause flooding of packets to find routes in a VANET. Hence, finding a route from the source to the destination vehicle by local broadcast techniques in densely populated urban areas may create a broadcast storm and network bandwidth is unnecessarily wasted to discover routes between source and destination vehicles. In this paper, an efficient routing …

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Regional Ionospheric Trend Statistics: Ionolab-Pdf, Ozan Köroğlu, Feza Arikan Jan 2017

Regional Ionospheric Trend Statistics: Ionolab-Pdf, Ozan Köroğlu, Feza Arikan

Turkish Journal of Electrical Engineering and Computer Sciences

The ionosphere plays an important role for HF bands, space-based positioning systems, satellite communication, and propagation. The variability of the ionosphere has a complex spatiotemporal characteristic, which depends on statistical parameters. Total electron content (TEC) is one of the major observables for investigating and determining this variability. In this study, spatiotemporal within-the-hour statistical characteristics of TEC are determined for Turkey, which is located in midlatitude, using the TEC estimates from the Turkish National Permanent GPS Network-Active between the years 2009 and 2012. The TEC values have strong hourly, seasonal, and positional dependence on east-west direction, and the trend shifts according …

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Using Latent Semantic Analysis For Automated Keyword Extraction From Large Document Corpora, Tuğba Önal Süzek Jan 2017

Using Latent Semantic Analysis For Automated Keyword Extraction From Large Document Corpora, Tuğba Önal Süzek

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, we describe a keyword extraction technique that uses latent semantic analysis (LSA) to identify semantically important single topic words or keywords. We compare our method against two other automated keyword extractors, Tf-idf (term frequency-inverse document frequency) and Metamap, using human-annotated keywords as a reference. Our results suggest that the LSA-based keyword extraction method performs comparably to the other techniques. Therefore, in an incremental update setting, the LSA-based keyword extraction method can be preferably used to extract keywords from text descriptions from big data when compared to existing keyword extraction methods.

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Breast Boundary Segmentation In Thermography Images Based On Random Walkers, Mehrdad Moghbel, Syamsiah Mashohor, Rozi Mahmud, M.Iqbal Bin Saripan, Suzana Abd Hamid, Suraini Mohamad Sani, Saiful Nizam Jan 2017

Breast Boundary Segmentation In Thermography Images Based On Random Walkers, Mehrdad Moghbel, Syamsiah Mashohor, Rozi Mahmud, M.Iqbal Bin Saripan, Suzana Abd Hamid, Suraini Mohamad Sani, Saiful Nizam

Turkish Journal of Electrical Engineering and Computer Sciences

Breast and areola boundary detection and segmentation present the biggest challenge in breast segmentation from thermography images, as breast boundaries, especially in the upper quadrants of the breast, are nonexistent. Many segmentation approaches have been proposed for breast segmentation, such as active contours and snakes, circular Hough transforms, and live wires, but these methods often fail to achieve satisfactory results. With recent advances in image processing techniques, new segmentation concepts are being developed, such as random walkers, which have received high interest from the medical imaging community. In this study, 91 images acquired utilizing a FLIR A320 thermal camera are …

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Error Sources And Measurement Uncertainties In Outdoor Testing Of Bipv Modules, Kivanç Başaran Jan 2017

Error Sources And Measurement Uncertainties In Outdoor Testing Of Bipv Modules, Kivanç Başaran

Turkish Journal of Electrical Engineering and Computer Sciences

Although building-integrated photovoltaic (BIPV) systems have great potential, investment in this field is not at the desired level. There are two main reasons for this: the lack of technical analysis and economic reasons. Manufacturers and investors utilize datasheets of modules to determine the systems performance, which is determined at standard test conditions (STCs). However, there are apparent differences between STCs and outdoor measurements. Most studies in the field of BIPV system analysis have only focused on long-term outdoor measurements. Besides that, uncertainty of measurements is necessary to achieve scientific results. The aim of this study is to emphasize the importance …

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Accelerating The Solving Of Nonlinear Equations Using The Homotopy Method: Application On Finding The Operating Point Of Complex Circuits, Fathi Dhiabi, Mohamed Boumehraz Jan 2017

Accelerating The Solving Of Nonlinear Equations Using The Homotopy Method: Application On Finding The Operating Point Of Complex Circuits, Fathi Dhiabi, Mohamed Boumehraz

Turkish Journal of Electrical Engineering and Computer Sciences

Analog circuits with nonlinear elements (e.g., diode, BJT, and CMOS) and integrated circuits are very complex systems. As a result, they are very difficult to analyze because of the need to generate a nonlinear equation system solution in order to do so. Solving nonlinear equations is still a challenging problem. Iterative methods, however, are frequently used to solve them. This paper describes a method that can be used to both accelerate the solving of nonlinear equations and find the operating point in various integrated circuits by construction of the global homotopy equation of the analog circuit. This is done by …

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Load Shedding Scheme Based On Frequency And Voltage Stability For An Islanding Operation Of A Distribution Network Connected To Mini-Hydro Generation, Norazliani Md Sapari, Hazlie Bin Mokhlis, Javed Ahmed Laghari, Ab Halim Abu Bakar, Hasmaini Mohamad, Mohd Rohaimi Mohd Dahalan Jan 2017

Load Shedding Scheme Based On Frequency And Voltage Stability For An Islanding Operation Of A Distribution Network Connected To Mini-Hydro Generation, Norazliani Md Sapari, Hazlie Bin Mokhlis, Javed Ahmed Laghari, Ab Halim Abu Bakar, Hasmaini Mohamad, Mohd Rohaimi Mohd Dahalan

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a load shedding scheme (LSS) based on system frequency and voltage stability (VS). In the proposed scheme, the amount of power imbalance is determined using a rate of change of frequency, and the load shedding priority is carried out based on a VS index. The load with the highest tendency for voltage collapse (based on the index value) is given first priority to be shed. Thus, by shedding the most sensitive load, the distribution system can be saved from power collapse and then the system can return to its nominal state after load shedding. The proposed LSS …

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Design Of A Low-Power Cmos Operational Amplifier With Common-Mode Feedback For Pipeline Analog-To-Digital Converter Applications, Sohiful Anuar Zainol Murad, Izatul Syafina Ishak, Mohd Fairus Ahmad, Shaiful Nizam Mohyar Jan 2017

Design Of A Low-Power Cmos Operational Amplifier With Common-Mode Feedback For Pipeline Analog-To-Digital Converter Applications, Sohiful Anuar Zainol Murad, Izatul Syafina Ishak, Mohd Fairus Ahmad, Shaiful Nizam Mohyar

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes a design of a low-power operational amplifier (op-amp) for pipeline analog-to-digital converter (ADC) applications using a 0.13-$\mu $m CMOS process. The folded-cascode topology with NMOS input types is employed for the op-amp design due to a larger output gain compared to PMOS input types. Furthermore, the op-amp is designed with a double detection structure of a common-mode feedback circuit to provide stable feedback voltage. The simulation results show that the proposed op-amp achieved a gain of 64.5 dB and a unity gain bandwidth of 695.1 MHz with a low power consumption of 0.14 mW. In addition, by …

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Design Optimization Of A ĆUk Dc/Dc Converter Based On Reliability Constraints, Amirreza Zarrin Gharehkoushan, Mehdi Abapour, Amir Farakhor Jan 2017

Design Optimization Of A ĆUk Dc/Dc Converter Based On Reliability Constraints, Amirreza Zarrin Gharehkoushan, Mehdi Abapour, Amir Farakhor

Turkish Journal of Electrical Engineering and Computer Sciences

Recently, power electronic converters have widely been used in various applications. This has led to concerns about the reliability of power converters and, as a result, their optimal design has attracted a lot of attention. However, the reliability-based optimal design of the Ćuk DC-DC converter has not yet been studied. A new methodology is presented here for the optimal design of the Ćuk converter based on reliability constraints. In this study, the converter is designed to minimize power losses in order to maximize the mean time to failure of the converter. A genetic algorithm is used as the optimization technique, …

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Eccentricity Fault Diagnosis In A Permanent Magnet Synchronous Motor Under Nonstationary Speed Conditions, Mustafa Eker, Mehmet Akar Jan 2017

Eccentricity Fault Diagnosis In A Permanent Magnet Synchronous Motor Under Nonstationary Speed Conditions, Mustafa Eker, Mehmet Akar

Turkish Journal of Electrical Engineering and Computer Sciences

Electric motor faults decrease production capacity and increase maintenance costs. Today, predictive detection based on real-time monitoring and fault detection is taking the place of periodic applications. In this study, a new method is presented for the detection of eccentricity faults in permanent magnet synchronous motors. The motor current and the rotor speed were monitored under stationary and nonstationary speed and different load conditions, after which the fault detection was carried out via angular domain-order tracking method. The obtained results were compared with traditional fast Fourier transform results. It was observed that the suggested method can successfully detect the fault …

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Intrusion Detection In Network Flows Based On An Optimized Clustering Criterion, Jaber Karimpour, Shahriar Lotfi, Aliakbar Tajari Siahmarzkooh Jan 2017

Intrusion Detection In Network Flows Based On An Optimized Clustering Criterion, Jaber Karimpour, Shahriar Lotfi, Aliakbar Tajari Siahmarzkooh

Turkish Journal of Electrical Engineering and Computer Sciences

Graph-based intrusion detection approaches consider the network as a graph and detect anomalies based on graph metrics. However, most of these approaches succumb to the cluster-based behavior of the anomalies. To resolve this problem in our study, we use flow and graph-clustering concepts to create a data set first. A new criterion related to the average weight of clusters is then defined and a model is proposed to detect attacks based on the above-mentioned criterion. Finally, the model is evaluated using a DARPA data set. Results show that the proposed approach detects the attacks with high accuracy relative to methods …

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Mobility And Load Aware Radio Resource Management In Ofdma Femtocell Networks, Mohammad Zarei, Behrouz Shahgholi Ghahfarokhi, Mehdi Mahdavi Jan 2017

Mobility And Load Aware Radio Resource Management In Ofdma Femtocell Networks, Mohammad Zarei, Behrouz Shahgholi Ghahfarokhi, Mehdi Mahdavi

Turkish Journal of Electrical Engineering and Computer Sciences

Recent evolutions in mobile networks have led to increased resource demands, especially from indoor users. Although recent technologies such as LTE have an important role in providing higher capacity, indoor users are not satisfied adequately. Femtocell networks are one of the proposed solutions that support high data rates as well as better indoor coverage without imposing heavy costs to network providers. However, interference management is a challenging issue in femtocell networks, mainly due to dense and random deployment of femto access points (FAPs). Therefore, distinct radio resource management (RRM) methods are employed to ensure acceptable levels of call dropping/blocking probability …

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Annual Summary Of Weather Data For Parsons, M. Knapp Jan 2017

Annual Summary Of Weather Data For Parsons, M. Knapp

Kansas Agricultural Experiment Station Research Reports

Annual Summary of Weather Data for Parsons, Kansas, 2016.

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Key Components Of Healthy Soils And Their Role In Crop Production, C. J. Hsiao, Gretchen Sassenrath, Charles Rice, L. Zeglin, G. Hettiarachchi Jan 2017

Key Components Of Healthy Soils And Their Role In Crop Production, C. J. Hsiao, Gretchen Sassenrath, Charles Rice, L. Zeglin, G. Hettiarachchi

Kansas Agricultural Experiment Station Research Reports

Soil health is a confusing term that means different things to different people. To a crop producer, healthy soils are critical for good crop growth and yield. Some soil properties include soil texture, such as the relative percentage of sand, silt and clay; the water content; nutrient levels; organic carbon content; the microbial community; and microbial activity. These properties are determinants of soil health. Our research confirmed that changes in soil management affect the composition and activity of soil microorganisms in surface soils. Greater concentrations of microbial biomass and arbuscular mycorrhizal fungus (AMF) in the no-till agricultural system indicated healthier …

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Measuring Soil Electrical Conductivity To Delineate Zones Of Variability In Production Fields, Gretchen Sassenrath, S. Kulesza Jan 2017

Measuring Soil Electrical Conductivity To Delineate Zones Of Variability In Production Fields, Gretchen Sassenrath, S. Kulesza

Kansas Agricultural Experiment Station Research Reports

Production fields in southeast Kansas are highly variable. Differences in elevation and changes in soil texture contribute to unevenness in plant-available moisture and nutrients, resulting in significant inconsistencies in crop production and yield within a field. These variabilities complicate management and impact the return on investments from different areas of the field. Identification of the regions of variability is possible through several methods, including visual inspection, remote imagery, and yield maps. An additional method of assessing soil variability is by measuring the electrical conductivity of the soil. Measuring apparent electrical conductivity gives a map of the spatial distribution of soil …

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