Multiple input multiple output (MIMO) array

In this paper, we propose a feedback-efficient hybrid precoding framework for wideband millimeter-wave (mmWave) multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems. To mitigate the high cost of radio frequency (RF) chains and channel state information (CSI) feedback in large-scale antenna arrays, we first construct frequency-flat analog precoders by extracting dominant angle-of-arrival (AoA) and angle-of-departure (AoD) directions from sparse frequency-domain channels. For digital precoding, we design a quantized codebook using the Lloyd algorithm and develop a binary-search-based hierarchical interpolation algorithm that adaptively assigns codewords according to subcarrier correlation. The proposed method achieves sublinear feedback scaling by reducing the feedback overhead from O(K) to O(K/M +log M), where K is the number of subcarriers and M is the pilot spacing. Simulation results demonstrate that the proposed method achieves comparable or superior spectral efficiency and bit error rate (BER) performance to existing clustering and interpolation schemes, while significantly reducing computational complexity and exhibiting robustness under imperfect CSI.

Window ventilation usually used in energy-efficient buildings as an effective natural ventilation system to provide an adequate opening for fresh air to flow into the interior space. It could help to reduce the indoor air temperature and limit the contaminants in buildings. This study aimed to visualise the airflow structure across a wooden louvred window panel using the smoke flow visualisation technique at different airflow speeds of 0.5, 1.0, 2.0, 3.0 and 5.0 m/s in a closed-loop wind tunnel. Two Sony 1920 × 1080i cameras captured the airflow structure, which took the side view, rear view, front view and back view images. The wooden louvred window panel promotes optimum outdoor airflow and facilitates continuous air exchange to replace the indoor air. Results showed that smoke filled the space quickly at the highest airflow speed of 5 m/s. This study used an inclination angle of 75° for the wooden louvred window panel to avoid rain splatter. Besides, wood material could be used as a façade shading device. Therefore, installing the wooden louvred window panels could enhance natural ventilation, ensure indoor thermal comfort and reduce indoor air contaminants.

This article is devoted to develop a numerical approximation called Taylor minimization method for initial and boundary value fractional Pantograph equations, which governs the modelling of the train system, with neutral and multi-term delays. Taylor optimization technique is basically composed of truncated Taylor series approximation of unknown function while employment of procedure is accompanied by an optimization strategy that is simulated annealing for carrying out the learning phase of unknown Taylor series coefficients. The proposed technique is implemented on various models of Pantograph equations to study the applicability and effectiveness of the planned scheme while error analysis and comparison with previous methods are performed to validate the results. To measure the capability of convergence the data for 100 numbers of independent runs is demonstrated in the form of pictorial presentation.

Distributed large-scale MIMO is a promising option for coping with the projected explosion in mobile traffic. It involves multiple Access Points (APs) that are connected to a central server via wired backhaul and act as a distributed MIMO transmitter, serving multiple users via spatial precoding. As is well known, large downlink (DL) spectral efficiencies can be achieved with TDD operation, pilots sent in the uplink (UL), and DL-UL channel reciprocity. With APs made of inexpensive hardware and connected via, e.g., Ethernet, synchronization and reciprocity calibration are the main hurdle for implementing a truly distributed MU-MIMO system. This work studies mechanisms for RF calibration that can enable distributed high-performing large-scale MIMO operation. We propose methods for relative calibration of the APs in order to ensure TDD reciprocity while not relying on an explicitly self-calibrating RF design. As our analysis and simulations suggest, the proposed methods significantly outperform existing self calibration methods without requiring additional signaling overhead and can enable TDD reciprocity for calibration of noncolocated networks.

The need and importance of Smart Spaces have been potentially realized by the researchers due to its applicability in the current lifestyle. Opportunistic network, a successor of mobile ad hoc networks and a budding technology of network, is a best-suited technology for implementing Smart Spaces due to its wide range of applications in real-life scenarios ranging from building smart cities to interplanetary communication. There are numerous routing protocols which are available in opportunistic network, each having their pros and cons; however, no research till the time of listing has been done which can quantitatively demonstrate the maximum performance of these protocols and standardize the comparison of opportunistic routing protocols which has been a major cause of ambiguous performance evaluation studies. The work here presents a categorical view of the opportunistic routing protocol family and thereby compares and contrasts the various simulators suited for their simulation. T...

Ornamental horticulture in Mexico is a growing industry that requires the inclusion of various technologies to automate production and marketing in order to increase its profitability. For this, data analysis is key, allowing obtaining knowledge to support decision-making; However, it involves exhaustive information processing time, affecting the productivity of companies due to the lack of a decision support system that implements dynamic business intelligence tools. This research work proposes a business intelligence web system for the creation of dynamic tools and execution of asynchronous queries to the database; which provides an analysis of the historical information on the commercialization of ornamental plants through tables, graphs and reports. It is developed using the PUA methodology, the Python programming language and the Django framework, employing an innovative approach by applying the DFS algorithm as a search mechanism to determine the relationship between the database tables, reducing extraction time, processing , analysis and presentation of information. As a result, it was possible to improve the use of historical information, streamline the processing and analysis of marketing information and, consequently, improve decision-making processes.

The need and importance of Smart Spaces have been potentially realized by the researchers due to its applicability in the current lifestyle. Opportunistic network, a successor of mobile ad hoc networks and a budding technology of network, is a best-suited technology for implementing Smart Spaces due to its wide range of applications in real-life scenarios ranging from building smart cities to interplanetary communication. There are numerous routing protocols which are available in opportunistic network, each having their pros and cons; however, no research till the time of listing has been done which can quantitatively demonstrate the maximum performance of these protocols and standardize the comparison of opportunistic routing protocols which has been a major cause of ambiguous performance evaluation studies. The work here presents a categorical view of the opportunistic routing protocol family and thereby compares and contrasts the various simulators suited for their simulation. T...

e need and importance of Smart Spaces have been potentially realized by the researchers due to its applicability in the current lifestyle. Opportunistic network, a successor of mobile ad hoc networks and a budding technology of network, is a best-suited technology for implementing Smart Spaces due to its wide range of applications in real-life scenarios ranging from building smart cities to interplanetary communication. ere are numerous routing protocols which are available in opportunistic network, each having their pros and cons; however, no research till the time of listing has been done which can quantitatively demonstrate the maximum performance of these protocols and standardize the comparison of opportunistic routing protocols which has been a major cause of ambiguous performance evaluation studies. e work here presents a categorical view of the opportunistic routing protocol family and thereby compares and contrasts the various simulators suited for their simulation. ereafter, the most popular protocols (selecting at least one protocol from each category) are compared based on node density on as many as 8 standard performance metrics using ONE simulator to observe their scalability, realism, and comparability. e work concludes by presenting the merits and demerits of each of the protocols discussed as well as specifying the best routing protocol among all the available protocols for Smart Spaces with maximum output. It is believed that the results achieved by the implemented methodology will help future researchers to choose appropriate routing protocol to delve into their research under different scenarios.

Distributed large-scale MIMO is a promising option for coping with the projected explosion in mobile traffic. It involves multiple Access Points (APs) that are connected to a central server via wired backhaul and act as a distributed MIMO transmitter, serving multiple users via spatial precoding. As is well known, large downlink (DL) spectral efficiencies can be achieved with TDD operation, pilots sent in the uplink (UL), and DL-UL channel reciprocity. With APs made of inexpensive hardware and connected via, e.g., Ethernet, synchronization and reciprocity calibration are the main hurdle for implementing a truly distributed MU-MIMO system. This work studies mechanisms for RF calibration that can enable distributed high-performing large-scale MIMO operation. We propose methods for relative calibration of the APs in order to ensure TDD reciprocity while not relying on an explicitly self-calibrating RF design. As our analysis and simulations suggest, the proposed methods significantly outperform existing self calibration methods without requiring additional signaling overhead and can enable TDD reciprocity for calibration of noncolocated networks.

The biggest challenge for natural language processing systems is to accurately identify and classify the handwritten characters. Accurate Handwritten Character recognition is a challenging task for humans too as the style, size and other handwriting parameters may vary from human to human. Though a relatively straightforward machine vision task but improved accuracy as compared to the existing implementations is still desirable. This manuscript aims to propose a novel neural network based framework for handwritten character recognition. The proposed neural network based framework, transforms the raw data set to a NumPy array to achieve image flattening and feeds the same into a pixel vector before feeding it into the network. In the neural network, the activation function is applied to transfer the resultant value to the hidden layer where it is further minimized through the use of minimized mean square and back propagation algorithms before applying a stochastic gradient on the resultant mini-batches. After a detailed study, the optimal algorithm for effective handwritten character recognition was proposed. Initially, the framework has been simulated only on digits through 50,000 training data samples, 10,000 validation data set and 10,000 test data set, the accuracy of 96.08. This manuscript aims to give the reader an insight into how the proposed neural network based framework has been applied for handwritten digit recognition. It highlights the successful applications of the same while laying down the directions for the enhancements possible.

The study aims to collect the main approaches proposed on the treatment and formal representation of machine tools, with special emphasis on both proposals that the authors consider as references and those from standarization domain. Based on this analysis, a schema is developed that incorporates the chronological evolution of the modeling of machine tools and the works oriented to their unifying. Finally, an outline of the future orientation of this line of work is also included.

Time Reversal (TR) applied to wireless communications systems has already shown very promising results at low Signal-to-Noise Ratio (SNR). In this paper, we describe a prototype implementing the Receive Antenna Shift Keying (RASK) modulation scheme combined with TR. RASK modulation consists in focusing a signal onto one receive antenna among several antennas. The index of the target receive antenna is updated every symbol duration and is coded by the binary sequence to be transmitted during the considered symbol. For spatial signal focusing, TR pre-filtering technique is used at the transmitter side. In this study, we also propose a very simple and efficient way to discriminate the collected information at the receiver side. This technique allows receivers with low complexity to be implemented in a multiple-input multiple-output (MIMO) configuration. Moreover, we evaluate the performance of RASK modulation according to the number of antennas at the transmitter and receiver side and demonstrate the feasibility of our approach in a realistic scenario.

En este artículo se propone un modelo para la predicción de demanda de energía eléctrica a corto plazo empleando técnicas de estimación Set Membership. El modelo está compuesto por una componente periódica y una componente no-lineal auto-regresiva generada por un modelo no-paramétrico adaptable que incorpora datos recientes al conjunto de identificación en cada iteración del algoritmo. El modelo es evaluado en un caso de estudio con mas de 13,000 muestras de demanda horaria a lo largo de tres años, registradas en un municipio rural de Colombia. El desempeño del estimador se compara con un modelo lineal auto-regresivo y un modelo Set Membership con conjunto de identificación fijo. Los resultados muestran que el estimador propuesto logra predecir la demanda de energía con un error RMS inferior al 2.5 % en datos de validación, empleando solo un 5 % de los datos disponibles para la construcción del modelo.

The biggest challenge for natural language processing systems is to accurately identify and classify the handwritten characters. Accurate Handwritten Character recognition is a challenging task for humans too as the style, size and other handwriting parameters may vary from human to human. Though a relatively straightforward machine vision task but improved accuracy as compared to the existing implementations is still desirable. This manuscript aims to propose a novel neural network based framework for handwritten character recognition. The proposed neural network based framework, transforms the raw data set to a NumPy array to achieve image flattening and feeds the same into a pixel vector before feeding it into the network. In the neural network, the activation function is applied to transfer the resultant value to the hidden layer where it is further minimized through the use of minimized mean square and back propagation algorithms before applying a stochastic gradient on the resultant mini-batches. After a detailed study, the optimal algorithm for effective handwritten character recognition was proposed. Initially, the framework has been simulated only on digits through 50,000 training data samples, 10,000 validation data set and 10,000 test data set, the accuracy of 96.08. This manuscript aims to give the reader an insight into how the proposed neural network based framework has been applied for handwritten digit recognition. It highlights the successful applications of the same while laying down the directions for the enhancements possible.

Es vital conseguir la disponibilidad adecuada para la consecución de los procesos productivos o de
servicios, garantizando la fiabilidad de las instalaciones o maquinaria. Muchas veces el aspecto
“eficiencia energética”, se estudia de una manera separada considerándolo principalmente como un
factor económico que redunda en la explotación de grandes instalaciones constructivas. Los factores
fiabilidad, mantenibilidad y eficiencia energética, están íntimamente relacionados, y deben ser estudiados
de manera conjunta para la optimización operativa de la planta industrial o edificio de servicios. Este
artículo, trata de plasmar las relaciones entre los tres factores, como interactúan entre ellos, y las mejoras
que pueden redundar sobre las infraestructures.

En el diseño de una nueva planta o construcción industrial, afectará de manera crónica las decisiones
tomadas en el primer momento (fiabilidad de las instalaciones y equipamiento, reducción tiempos
paradas, eficiencia energética, acciones medioambientales). En este artículo se presenta un estudio de
caso de una planta industrial donde el diseño está basado en la mejora de la fiabilidad, mantenimiento y
explotación eficiente, así como la eficiencia energética y el respeto medio-ambiental, donde los procesos
y decisiones

An ever crowed Radio spectrum system implies that future demands must be met using more data throughput wireless technologies. Since system bandwidth is limited and user demand continues to grow. This problem could be solved by WiMAX (Worldwide Interoperability for Microwave Access) technology based on the IEEE 802.16 specifications. Since it offers high level of services. In this paper the performance of Turbo Coded WiMAX system over different Channels like AWGN, Rayleigh & Rician has been analysed. And the performance of each channel is compared with the performance as was with convolution code (without Turbo) and performance at different iterations in Turbo code. Orthogonal Frequency Division Multiplexing have been used to achieve high data rate necessary for intensive application by maintaining FFT size 256. With result we could say that AWGN channel with more number of iterations shows better result. With Convolution code (without Turbo)performance was weak, it enhanced approx. 7db by the use of Turbo code.

Construction companies' workers are facing higher injury rates as compared to other industries. The principal objective of this research is to investigate occupational health and safety (OH&S) training to be delivered effectively to the workers of the construction companies. The awareness level of employees' about OH&S and how to facilitate the employees for OH&S training to consequently have been studied. Both quantitative and qualitative method of study is implied collected by using construction self-administered questionnaire and face-to-face interviews. Statistical tools like frequency distribution and chi-square test has been used. Data obtained then examined by applying SPSS (Statistical Package for the Social Sciences) software. Three hundred respondents participated in the researcher's study to make the research valuable. It has been observed that levels of OH&S knowledge vary from workers of various construction companies. It has also been investigated that varies how the construction workers been trained in OH&S.

In this research paper, we will focused on the bit error rate (BER) performance of Orthogonal-frequency division multiplexing (OFDM) of various modulation techniques. The Orthogonal Frequency Division Multiplexing (OFDM) is the popular modulation technique for the many wireless communication systems. In the wireless system, the signal transmitted into channel bounces off from the various surfaces resulting in the multiple delayed versions of the transmitted signal arriving to the receiver. The OFDM has trusted to be very effective in mitigating adverse multi-path effects of a broadband channel. The multiple signals are obtained due to the diffraction and reflection of electromagnetic waves around objects .The bit error rate (BER) performance of this type of systems are evaluated in the additive white Gaussian noise (AWGN) channel. The BER performance of the transmission modes are calculated by calculating the bit error rate (BER) versus signal to the noise ratio (SNR) under the Additive white Gaussian noise (AWGN), channel.

It is well known that Multiple Input-Multiple Output systems enhance the spectral efficiency significantly of wireless communication systems. However, their remarkable hardware and computational burden hinders the wide deployment of such architectures in modern systems. It is a big challenge to reduce hardware complexity, use power with flexible capacity, data rate and bit error rate for the MIMO technology. In this paper we give a theoretical overview of several important theoretical concepts which is related to MIMO. The main part of this thesis can be considered as a most efficient decision for highest capacity with the reasonable BER performance. Hence we came up with an idea to write this thesis paper where we investigated the techniques which we can utilize in order to increase capacity (Bit/s/Hz) and hence provide the less BER in MIMO system. For this system we use Hybrid selection/Maximal-ratio transmission technique over a faded correlated MIMO quasi-static channel. Here faded correlated channel has the ability to carry high capacity data and HS/MRT technique minimizes the BER of system. For this system we use MSK modulation technique which reduces the complexity at transmission side. In practically, For more complexity free in this technique excludes the up converter, amplifier and filtered stage which also alleviate the cost. In this paper at first we try to focus the main important related techniques used in MIMO with the advantages and drawbacks. Then we review the MIMO system from the several past paper works and then we compare the performance of this technique. From this comparison result and using best technique we suggest a future work which will give the best performance. Finally, we describe the technique which we used in our suggested work.

Renewable energy production in terms of solar irradiation comes is highly valuable for power generation. The World Bank Group (WB) investigated the quantity of intermittent renewable energy usage in regard to explore the existing solar power availability in Pakistan. The WB group put a strong effort to explore the renewable resources in the number of countries including Pakistan. The WB get the data available for all the observed countries. So the data obtained from WB sites located across Karachi. The solar data was studied by the WB group for the data sets in 2015-2017. In this paper, we have observed the solar irradiation trend and the fluctuation as for as the sunny day is concerned for the hourly, daily, monthly and yearly durations. The solar irradiations to be able to efficiently employ these renewable energy sources to meet the current and future power needs of Karachi of Pakistan. The Solar irradiation is available in the form of energy only need to explore it. We must use the python software for the solar irradiation trend observation for the Karachi.

Most Higher Education Institutions (HEI) are trying to achieve a Green ICT Campus as part of its responsibility for building a sustainable environment. Efficient energy distribution is one of the key factors to achieve the maximum benefits of producing clean and green energy. The importance of renewable energy generation and distribution synchronized by ICT for achieving a green campus in Malaysian Higher Education Institution (MHEI) are suggested and discussed here. This research paper focuses on studying the current practices in energy usage in MHEI and proposing various techniques to reduce the consumption of energy usage to achieve Green ICT Campus through the Smart Grid including suggesting for alternate energy production. The obtained results show that the energy consumption was reduced to a significant level of 30% when tested for one HEI, which plays a key role in fulfilling the green computing requirements and provides a pathway to realizing a green campus. With these findings, it is envisaged that this system optimizes energy usage and could be applicable for any MHEI.

Forecasting short-term electrical load is very important so that the quality of the electrical power supplied can be maintained properly. The study was conducted to measure the results of electrical load forecasting based on parameter estimates and the presentation of time series data. It is important to manage stationary data, both in terms of mean and variance. Data presentation is done by determining the value of variance through the Box-Cox transformation method and the mean value based on the ACF and PACF plots. This study considers the pattern of electricity consumption which contains double seasonal patterns. The results of previous studies show the electric power prediction model, the DSARIMA model ([

Research Scholar Assistant Professor Principal RIET Phagwara CSE Deptt, RIET RIET Phagwara ---------------------------------------------------------------------***---------------------------------------------------------------------Abstract— Transmission in OFDM system is carried out using different encoding schemes and channel equalization techniques so that errors in sub-carriers can be removed to accomplish efficient communication. To this end, significant numbers of authors have developed various techniques. One of the techniques giving efficient results utilized Low-Density Parity Check Code (LDPC) coding technique the e but this technique can give enhanced results. In this thesis, a novel model is developed. The system is proposed by utilizing spacetime trellis code (STTC) for encoding and decoding the signal. This approach is helpful in diminishing the bit error rate. Along with this, noise in the channels is also removed by introducing ML equalizer. Three different types of ...

Code Division Multiple Access (CDMA) performs well in a multi-cellular environment where a single frequency is used in all cells. Code Division Multiple Access (CDMA) has severe problems associated with multipath and Channel news. One possible problem is that the receiver may require a very large dynamic range in order to handle the large signal strength variation among users. Due to that the Bit Error Rate (BER) is getting increased. Moreover due to the addition of uncontrollable random channel noise degrade the performance of the receiver. The multipath problems give inter symbol interference. This can be reduced by Orthogonal Frequency Division Multiplexing (OFDM) technique. More work could be done on investigating suitable techniques for doing OFDM promises to be a suitable modulation technique for high capacity wireless communications and will become increasing important in the future as wireless networks become more relied on. In order to increase the wireless network performance, this study has concentrated on OFDM with a novel forward error correction by data transmission with Quadrature Phase Shift Keying (QPSK) as modulation techniques. Here an FEC scheme by concatenation of Reed Solomon (RS) and the Irregular Turbo code is implemented in OFDM. The simulation results show that the system BER performance is decreased with this technique, when compared to the system having Forward Error Correction (FEC) by RS code alone and irregular turbo code alone.

There are scenarios in wireless networks where a fully connected path between nodes for communication through a network is not the case and yet nodes still need to communicate freely. Despite concerted efforts to resolve this problem of unconnected wireless nodes trying to relay crucial information, network users still experience significant communication challenges owing to failures or non-existence of critical infrastructural links between nodes and their security challenges. Node cooperation technique was developed and incorporated into the security aided and groups encounter PRoPHET routing protocol with cooperative behavior modelled for three nodes as shown in the cooperative behavior equation. This is in order to improve its security to ensure availability and to resist malicious dropping in OpptNets where a node may refuse to act as a relay and only settle for sending and receiving its own data or information, thus, causing considerable delay degradation in the network. Results demonstrated that, the node cooperation improved the security aided and group encounter PRoPHET routing protocol as it improved the delivery probability by 25.7%, reduced the latency by 13.10%, improved the hop count by 62.9%, and improved the buffer time by 55.

Wireless communication is the heart of all the modern communications techniques. The future communication is mostly all about related to wireless communications. In wireless communication, different modulation methods are playing the vital roles. To combat the error in transmission channel coding techniques are very much necessary. In this paper, theoretical BER (bit error rate) analysis with Eb /No (Energy per Bit to Noise Power) has been done for various digital modulations techniques such as 8-PSK, 16-QAM and 64-QAM. The paper has also included various channel coding schemes such as block code and convolutional code in the analysis. For all the analysis, AWGN (Additive White Gaussian Noise) channel has been considered. General Terms Modulation methods, error control coding, wireless communication, Bit error rate analysis.