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Presently, buildings are expected to be designed to meet higher energy performance, sustainability to enjoy healthy and comfortable environment for the occupants. With the growing public awareness of environment issues, the energy efficient design concept for construction of buildings is being accepted to reduce the day-to-day energy demand of the buildings. In this scenario, net zero energy building design is one of the solutions to combat global warming by reducing energy demand and simultaneously use of renewable energy to run the operations of the building. In this paper, the focus is given on net zero energy building design criteria for composite climate zone. The technical parameters of planning, orientation, envelope, heating ventilation and air-conditioning (HVAC), use of energy efficient materials and integration of renewable energy system in designing the net zero energy building were analyzed and evaluated. The net zero energy balance equation was established from the building design strategies by evaluating the total annual energy demand, reduction in annual energy consumption implementing energy efficient technologies and annual renewable energy generation under the boundary of the building. This equation of net zero energy building was validated on design and construction of BISA building located at Ludhiana, Punjab falls under the composite climate zone. The analysis, evaluation and validation were carried out on system-generated model of the building. The reduced annual energy demand of the building of 432,742 kWh was met from the renewable energy generation of rooftop solar photovoltaic power plant of capacity 300kWp and satisfied the net zero energy balance equation.

In this paper, a novel watermarking technique for the tamper detection of text images is pro- posed. Entropy of every sentence is computed and Markov matrix using the occurrences of the characters is used to generate a character pattern. Entropy and character patterns are converted to Unicode Zero Width Characters (ZWCs) by using a lookup table. The ZWCs of entropy of each sentence is embedded at the end of every sentence after terminator. ZWCs of the character patterns are embedded in the end of the text of the image. On receiver side, ZWCs are extracted and converted to numerical form using the same lookup table. Entropy of every sentence and character patterns are recalculated and compared with extracted values for tamper detection. Comparison of technique with existing state-of-art techniques shows the effectiveness of the proposed technique.

Nonobstetric surgery during pregnancy is common. Administration of safe anesthesia to a pregnant patient, while minimizing its side effects on the fetus, is a major challenge for the anesthesiologist. Both general anesthesia and central neuraxial block are associated with risks during early pregnancy. Regional nerve blocks are being explored as possible alternatives whenever feasible. This report emphasizes the usefulness of ultrasound-guided, modified bilateral paravertebral block in a first-trimester pregnant patient undergoing microdiscectomy for cauda equina syndrome.

Functionally graded materials (FGM) are newly developed materials described by variation in the characteristics gradually over volume. These materials find applications in very high temperature environments namely aerospace industry, nuclear reactors, gas turbines, and electronics cooling. These materials are used in high temperature environments with dynamic load conditions, so their transient thermoelastic analysis under these conditions is necessary. In this paper, transient thermoelastic investigation of FGM is carried out using finite element method (FEM). The effect of temperature dependence is considered in the thermophysical properties of a FGM plate in the direction of its thickness. FEM is applied to solve the thermo mechanical equations and Newmark direct integration scheme is used for obtaining the solution for transient loading. This method improves the accuracy for three dimensional cases and produces solutions directly in time domain. A comparative study is made with some existing methods, and it is found that temperature and thermal stresses remain within safe limits at higher temperatures while preserving the deformation in the structure. The results show that the grading parameter has a dominating effect on transient thermoelastic behavior on FGM plate.

Existing tamper detection techniques for document images use the textual information of the image to create a zero watermark. These techniques cannot authenticate a document image if the image is tampered with in non-textual regions. In order to resolve this problem, a tamper detection technique for document images is proposed using the concept of zero watermarking. The input document image is transformed by applying lifting wavelet transform to get its subbands. These subbands are further partitioned into non-overlapping blocks of the same size. Features of each blocks are extracted to create a zero watermark. This watermark is combined with the key watermark in order to create a meaningful watermark. This meaningful watermark is stored by a trusted authority. On the receiver side, the meaningful watermark is compared to the watermark generated using tampered image to check the authenticity of the cover image. The tampered regions of the cover image can also be localized using this technique. The experimental results demonstrate the effectiveness of the technique in comparison to the existing authentication techniques.

Background: Intubation with either an endotracheal tube or a rigid bronchoscope is generally preferred to provide airway protection as well as to manage unpredictable complications during transbronchial lung cryobiopsy (TBLC). The laryngeal mask airway has been described as a safe and convenient tool for airway control during bronchoscopy. Aims and Objectives: In this study, we evaluated the safety and outcome of using a laryngeal mask airway (LMA) as a conduit for performing TBLC by flexible video bronchoscopy (FB). Methods: We retrospectively analyzed the database of the patients who underwent TBLC between November 2015 and September 2019. The procedure was performed using FB through LMA under general anesthesia. Prophylactic occlusion balloon was routinely used starting January 2017 onwards. Radial endobronchial ultrasound (R-EBUS) guidance was used for TBLC in the localized lung lesions when deemed necessary. Multidisciplinary consensus diagnostic yield was determined and periprocedural complications were recorded. Results: A total of 326 patients were analysed. The overall diagnostic yield was 81.60% (266/326) which included a positive yield of 82.98% (161/194) in patients with diffuse lung disease and 79.54% (105/132) in patients with localized disease. Serious bleeding complication occurred in 3 (0.92%) cases. Pneumothorax was encountered in 8 (2.45%) cases. A total of 9 (2.76%) cases had at least 1 major complication. Conclusion: This study demonstrates that the use of LMA during TBLC by flexible bronchoscopy allows for a convenient port of entry, adequate airway support and effective endoscopic management of intrabronchial haemorrhage especially with the use of occlusion balloon.

In this paper, a novel image steganography approach is proposed to enhance the visual quality of stego image. The cover image is decomposed using Discrete Wavelet Transform (DWT) to produce wavelet subbands and threshold value is calculated for each higher frequency wavelet subbands. Wavelet coefficients having magnitude larger than the threshold of its subband are selected to embed the secret data. Semi Hexadecimal Code (SHC) is proposed to convert pixel value of secret image into smaller equivalent value so that it distorts stego image as less as possible. Experimental results shows that maximum PSNR between cover image and stego image is more than 75 dB .Proposed approach is also compared with the existing approaches and this comparison shows that the proposed approach is better than the existing approaches.

A closed loop speed control scheme for a Permanent Magnet Brushless DC (PMBLDC) motor is implemented using single current sensor without position and speed sensors. The rotor position information is derived from the back emf of the motor and this in turn is used for determining the rotor speed. The various aspects of DSP based closed loop speed control (such as derivation of position, current sensing, speed controller and PWM generation) of the PMBLDC drive system are discussed. The DC link Current is sensed for feedback, which reduces the requirement of current sensor and hence limits the overall cost of the drive system.

This paper presents the performance analysis of interior permanent magnet synchronous motor (IPMSM) fed from improved power quality converter–inverter system as a variable speed drive for air-conditioning (Air-Con). The improved power quality converter (IPQC) makes the input power factor unity and also reduces the total harmonic distortion (THD) of input supply current. This converter consists of two uncontrolled unidirectional and two bi-directional switches. It provides constant DC-link voltage during transient and steady state conditions. This converter has high efficiency as only two switches conduct at a time and IPMSM also offers high efficiency as compared to other electric motors. The proposed drive system is an appropriate solution for energy conservation in the AC distribution system, in the motor and in the compressor of Air-Con. The detailed model and the simulated results of the proposed drive system are presented to demonstrate the features of improved power quality and energy conservation.

This paper presents important experimental findings on a novel 2-winding single phase self-excited induction generator (SEIG) through extensive experimentation. The performance of the generating unit has been critically evaluated in terms of voltage, frequency consistency, efficiency and sensitivity to realistic parameters. These results are expected to assess its suitability for practical application towards standby power generation. These results would guide on the needed requirements in the system.

This paper deals with the design and development of a photovoltaic (PV) array fed cage induction motor for an isolated water pumping system. A drive system using a chopper circuit to track power from the PV for different solar and a current controlled voltage source inverter (CC-VSI) to optimally match the motor to PV characteristics is presented. The model equations governing interaction of torque and flux producing components of motor current with available solar power is developed for the operation of the system at optimum efficiency. Performance of the system is presented for different realistic operating conditions, which demonstrates its special features for applications such as solar water pumping system, solar vehicles and flour mills located in hilly and isolated areas,.

This paper describes an experimental study carried out on a permanent magnet brushless DC (PMBLDC) motor drive coupled to a pump load powered by a photovoltaic (PV) array for water pumping system applications. A simple low-cost prototype controller has been designed and developed without current and position sensors which drastically reduces the overall cost of the motor drive system. This controller is used to test the dynamic behavior of the PMBLDC motor drive system. A mathematical model of the system is developed with a view to carrying out a comparison between the experimental and simulated response of the drive system. The necessary computer algorithm is developed to analyze the performance under different conditions of varying solar insolation for a pump load. The developed state-space equations are simulated to obtain the performance characteristics which are also verified by conducting a suitable experiment on the developed PV pumping system.

This paper deals with the reduction of overall cost of a current controlled voltage source inverter fed vector controlled induction motor drive (VCIMD). For this purpose an attempt has been made here to examine the possibility of such elimination/reduction in the number of sensors. The performance analysis of the VCIMD system (22 kW cage induction motor) is carried out and with the help of simulated results the effectiveness of the proposed elimination/reduction of sensors is assessed.

This paper deals with the power quality improvement of AC mains in Direct Torque-Controlled (DTC) permanent magnet synchronous motor (PMSM) drive using active wave shaping techniques. For this purpose, different topologies for active wave shaping of AC mains current in DTC-based PMSM drive such as single- and two-switch boost power factor correction (PFC) AC-DC converter, asymmetrical two-switch boost PFC AC-DC converter and single-phase voltage source AC-DC converter (VSC) are considered. The models are developed and simulated in MATLAB environment along with the Power System Blockset (PSB) and Simulink toolboxes to compute the relevant power quality performance indices. The simulated results demonstrate the effectiveness of different topologies in improving the power quality of the input AC mains in DTC-based PMSM drive.

The paper examines the dynamic response of the static synchronous series compensator (SSSC) with sliding-mode and fuzzy controllers. A current-controlled voltage-source inverter (CC-VSI) is used as an SSSC. It injects a sinusoidally varying voltage (0

The issues involved in the design of energy-efficient high-performance irrigation pump induction motors operating under typical field conditions are highlighted. Various factors deserving consideration, from the predesign survey to the final design stage, are discussed in detail. By resorting to optimisation techniques, suitable objective functions were evolved to arrive at an improved design, which is constrained by industrial practices and performance requirements. The new design is compared with the standard design, and its salient features are discussed to suggest useful guidelines.