The success of the dental restorations largely depends on its esthetics, although various literature reviews recommend that anterior teeth midline be placed coinciding the facial midline, the amount of acceptable deviation between facial and dental midline has not been fully investigated. To observe the acceptable deviation between the dental and facial midline. Facial photographs of 200 students aged about 18-30 years of both sexes, without any missing teeth, with complete alignment of anterior teeth, were selected and scanned on to computer screen. Using specialized programme, the crown width of the central incisor in the mouth and on photograph was ensured constant. The distance between the facial midline, (obtained by bisecting intercanthal line) and the mesial surfaces of the central incisors were read on the computer. 44.4 % Boys and 55 % of Girls showed deviation between dental and facial midline in the range of 0-1 mm. while, 54 % of boys and 33 % of girls showed deviation of the dental and facial midline in the range 1-2 mm. 37 % of boys and 8 % of girls showed deviation of dental midline with facial midline with the range of 2-3 mm. 80 % of the study population showed maxillary and mandibular dental midlines never coincide. Majority of the study population showed deviation between facial midline and anterior teeth midline within the range of 0-1 mm.

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The output power obtained from solar-wind hybrid system fluctuates with changes in weather conditions. These power fluctuations cause adverse effects on the voltage, frequency and transient stability of the utility grid. In this paper, a control method is presented for power smoothing of grid integrated PV/wind hybrid system using ultracapacitors in a DC coupled structure. The power fluctuations of hybrid system are mitigated and smoothed power is supplied to the utility grid. In this work both photovoltaic (PV) panels and the wind generator are controlled to operate at their maximum power point. The grid side inverter control strategy presented in this paper maintains DC link voltage constant while injecting power to the grid at unity power factor considering different operating conditions. Actual solar irradiation and wind speed data are used in this study to evaluate the performance of the developed system using MATLAB/Simulink software. The simulation results show that output power fluctuations of solar-wind hybrid system can be significantly mitigated using the ultracapacitor based storage system.

The present research investigations in power management fraternity are focused towards the realization of smart microgrid (MG) technologies. Due to intrinsic advantages of Direct Current (DC) system in terms of compatibility with power generation sources, modern loads and storage devices, DC MG has becoming popular over Alternate Current (AC) system. A secondary voltage and current control schemes of DC MG system are mainly based on the distributed consensus control of Multi-agent system (MAS) to balance generation and the demand. The basic concern of the cooperative control of MAS is consensus, which is to design a suitable control law such that the output of all agents can achieve synchronization. The distributed consensus algorithm requires much less computational power and information exchange in between the neighbor's agent. Meanwhile the other controllers such as model predictive control (MPC) requires accurate dynamic models with high computational cost and it suffers from lack of flexibility. The hierarchical consensus control technique is classified into three levels according to their features, namely primary, secondary, and tertiary. MAS is a popular distributed platform to efficiently manage the secondary control level for synchronization and communication among the power converters in autonomous MGs. In this article, various primary control techniques for local voltage control, voltage restoration in the secondary control level and tertiary control for energy management techniques are discussed. With this, the key emphasis to reduce the voltage deviation and disturbances in a heterogeneous DC MG network solutions are discussed. Furthermore, to analyze the system response and the charging and discharging characteristics of the battery unit, the developed second order heterogeneous consensus controller is compared with the traditional homogeneous consensus control and droop control methods. Finally a detailed discussion on simulation case study using heterogeneous consensus control method over the traditional methods are provided using MATLAB/Simulink platform.

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