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This article deals with the reduction of Inrush current. Analyzing of different techniques used for the reducing of Inrush current is done in this review paper is about how different techniques have been discussed to minimize inrush current from transformer in this review paper. Different techniques are compared which are used to minimize the inrush current. Due to these techniques inrush current which is drawn in transformer get reduced.

Traffic congestion is a common problem in any metropolitan city. Wastage of time, fuel, and environmental pollution can be reduced if smart parking systems are designed and implemented. Different types of smart parking systems have been deployed in various regions of the world, and these systems have shown three major problems. The systems require major upgrading of the parking space, which involves expensive work on the surface of the parking space. The nodes require a wired power supply or in some cases a regular battery change. Lastly, these systems require one node per parking spot making them expensive. The system described here addresses the above-mentioned bottlenecks. The developed system can monitor up to four parking spots with one node, the system transmits data via a wireless network and uses solar cells to operate thus making it maintenance free and eco-friendly. Moreover, these features make the system cheap to install and operate. It incorporates real-time monitoring of nodal data and provides the user with the current status of a parking space.

Internet of things [IoT] enables realization of the development of various intelligent systems and devices. In this scenario, intelligent waste management occupies an indispensable part in building smart cities. Furthermore, for improving the intensity and efficiency of waste monitoring system, we investigate the ways by which the garbage can be collected in the city and imitating new techniques to monitor all these processes. This paper proposes an idea of wireless garbage monitoring system with IoT as an underlying architecture. We can use this system to meet the actual garbage monitoring needs, and use of corresponding software system to achieve remote monitoring, that aims to minimize human intervention and improve the efficiency of human activities. Meanwhile, we have proposed a technical solution to build a simple garbage monitoring hardware and software system as a reference. It is believed that this trivial reference will give the platform to build a better design and its implementation.

Owing to increased performance capabilities over their LED counterparts, Gallium Nitride (GaN) based Laser Diodes (LDs) are becoming more prevalent in several applications, including lighting, visible light communications, medical spectroscopy, and atom cooling. For many of these applications, a tunable, precise wavelength is necessary such that chromatic aberrations are minimized and that specific wavelengths with narrow linewidth can be utilized for atomic transitions or filtered communications systems. This paper discusses one method of achieving single-mode lasing operation in GaN LDs, namely the deeply-etched sidewall grating Distributed Feedback (DFB) LD. Optical characteristics of such devices will be discussed, as well as their feasibility for optical communications.

Gallium nitride (GaN) sources are becoming a regular part of today's world and are now key devices for lighting infrastructures, communications systems and quantum applications, amongst others. In particular, many applications have seen the shift from LEDs to laser diodes to make use of higher powers, higher bandwidths and increased transmission distances. Laser communication systems are well established, however there are applications where the ability to select a single emitted wavelength is highly desirable, such as quantum atomic clocks or in filtered communication systems. Distributed feedback (DFB) lasers have been realised emitting at a single wavelength where the grating structure is etched into the sidewall of the ridge. The main motivation in developing these lasers is for the cooling of ions in atomic clocks; however their feasibility for optical communications is also explored. Narrow linewidth lasers are desirable and this paper will explore how this is achieved. Data rates in excess of 1 Gbit/s have also been achieved in a directly modulated, unfiltered system. These devices lend themselves towards wavelength division multiplexing and filtered optical communications systems and this will be analysed further in the work presented here.

In this work, we explore the nonlinear pulse dynamics in a SESAM-free, mode-locked electrically-pumped (EP) VECSEL. The laser setup is illustrated in Fig. 1 (left) and includes an EP-VECSEL chip, a curved output-coupler with a radius of curvature of 75 mm and 10 % out-coupling, and an adjustable intracavity slit directly in front of the output-coupler. The output-coupler is placed on a translation stage to allow for variation of the cavity length and a polarizing isolator is used for suppression of back-reflections.

Silica-based luminescent materials have gained significant attention over the last several years primarily to be used under integrated photonics. In this context Ce-doped silica are particularly interesting due to their potential to be used as Si-based light emitting sources [1]. In this work we have prepared a Ce-doped silica fiber that is drawn from a preform which is prepared using standard MCVD technology. In this work we study the spontaneous lifetime and fluorescence parameters of a Ce-doped silica fiber when pumped with 405 nm continuous wave laser.

We demonstrate a single wavelength operation from an InGaN/GaN distributed feedback (DFB) blue laser at 42X nm. The 39th order grating is etched in the sidewall to achieve single wavelength. The laser has a FWHM of ~ 25 pm at 500mA pulsed current with 15 mW output power.

We investigate the wavelength-tuning of cascade quantum-well GaSb-based diode lasers emitting at 3.2 µm. An external-cavity setup is used to demonstrate wavelength-tuning over a range of 250 nm with a maximum output power of 8.4 mW.

The Factored 3-way Restricted Boltzmann Machine has encoded the image transformation successfully. But when utilize the code to unknown image, the result was much affected by the feature of training samples. Based on the model, we separated the transformation feature out of the hidden representation and designed a new probabilistic model with gate for learning distributed representations of image transformations. Inference in the model consists extracting the transformation, find the mapping code, training filters to fit for the affine or more general transformations. We also provide experimental results to validate the performance of our model to a various tasks.

In this work an introduction to intelligent electric vehicle is presented. Design and development of intelligent vehicle for intelligent behavior quick output, cost is very cheap and it avoided the hurdle in his way so it is called safe intelligent electric vehicle. An introduction of intelligent vehicle that how it changes his performances according to the environment that can adapt the change as like environment. Also describes the application of intelligent machines. Intelligence machines number of areas like aerial navigation, sea and space exploration and multitalented robots are presented.

Internal quantum efficiency (IQE) of a high-brightness blue LED has been evaluated from the external quantum efficiency measured as a function of current at room temperature. Processing the data with a novel evaluation procedure based on the ABC-model, we have determined separately IQE of the LED structure and light extraction efficiency (LEE) of UX:3 chip. Full text Nowadays, understanding of LED efficiency behavior at high currents is quite critical to find ways for further improve­ment of III-nitride LED performance [1]. External quantum ef­ficiency ηe (EQE) provides integral information on the recom­bination and photon emission processes in LEDs. Meanwhile EQE is the product of IQE ηi and LEE ηext at negligible car­rier leakage from the active region. Separate determination of IQE and LEE would be much more helpful, providing correla­tion between these parameters and specific epi-structure and chip design. In this paper, we extend the approach of [2,3] to the whole range of the current/optical power variation, provid­ing an express tool for separate evaluation of IQE and LEE. We studied an InGaN-based LED fabricated by Osram OS. LED structure grown by MOCVD on sapphire substrate was processed as UX:3 chip and mounted into the Golden Dragon package without molding. EQE was measured with Labsphere CDS-600 spectrometer. Plotting EQE versus output power P and finding the power Pm corresponding to EQE maximum ηm enables comparing the measurements with the analytical rela­tionships ηi = Q/(Q+p1/2+p-1/2) ,p = P/Pm , and Q = B/(AC) 1/2 where A, Band C are recombination constants [4]. As a result, maximum IQE value equal to QI(Q+2) can be found from the ratio ηm/ηe plotted as a function of p1/2 +p1-1/2 (see Fig.la) and then LEE calculated as ηext = ηm (Q+2)/Q . Experimental EQE as a function of normalized optical power p is shown in Fig. 1 b along with the analytical approximation based on the ABC­model. The approximation fits perfectly the measurements in the range of the optical power (or operating current) variation by eight orders of magnitude. In conclusion, new express method for separate evaluation of IQE and LEE of III-nitride LEDs is suggested and applied to characterization of a high-brightness blue LED. With this method, we obtained LEE from the free chip surface to the air as 69.8% and IQE as 85.7% at the maximum and 65.2% at the operation current 350 rnA. [I] G. Verzellesi, D. Saguatti, M. Meneghini, F. Bertazzi, M. Goano, G. Meneghesso, and E. Zanoni, "Efficiency droop in InGaN/GaN blue light-emitting diodes: Physical mechanisms and remedies," 1. AppL Phys., vol. 114, no. 7, pp. 071101, Aug., 2013. [2] C. van Opdorp and G. W. 't Hooft, "Method for determining effective non radiative lifetime and leakage losses in double-heterostructure las­ers," 1. AppL Phys., vol. 52, no. 6, pp. 3827-3839, Feb., 1981. [3] M. Meneghini, N. Trivellin, G. Meneghesso, E. Zanoni, U. Zehnder, and B. Hahn, "A combined electro-optical method for the determination of the recombination parameters in InGaN-based light-emitting diodes," 1. AppL Phys., vol. 106, no. II, pp. 114508, Dec., 2009. [4] Qi Dai, Qifeng Shan, ling Wang, S. Chhajed, laehee Cho, E. F. Schubert, M. H. Crawford, D. D. Koleske, Min-Ho Kim, and Yongjo Park, "Carrier recombination mechanisms and efficiency droop in GalnN/GaN light-emitting diodes," App/. Phys. Leu., vol. 97, no. 13, pp. 133507, Sept., 2010. © 2014 IEEE.

Fluorescence properties of a Ce3+-doped silica fiber at different pump wavelengths between 405nm to 450 nm are investigated. With 405 nm pump wavelength and a fiber length of ∼130-140 cm broadband fluorescence of ∼280nm is achieved.