Design and Implementation of Efficient Smart Lighting Control System with Learning Capability for Dynamic Indoor Applications

Accurate and efficient adjustment of luminaire’s dimming level in a smart environment can be a huge challenge. Indoor lighting system as a nonlinear and time variant block, which consumes significant amount of electrical power is evaluated in this paper. In doing so, a control method is proposed to efficiently adjust luminaire’s dimming level in a smart environment and to optimize energy and user’s comfort level. The proposed control method takes advantages from neural network and its learning capabilities. In this research, photodetectors are placed at the work zones, where work zones can have different number of photodetectors without any increase in complexity and any adverse effect on the control system. The method is capable of adopting itself to daylight variations with high accuracy. A state machine is developed to implement the method. The method is implemented in MATLAB and lighting conditions are extracted in DIALux. Luminaire’s dimming levels are determined with accuracy higher than 99%. Daylight is considered as a bias to the system and thus the network does not need to be trained by any variations. In a dynamic condition, when taking into account the variation in daylight, the system mean error does not exceed 3%

Illumination Control of Smart Indoor Lighting Systems Consists of Multiple Zones

Accurate and power efficient determination of luminaires dimming level is a challenging issue in smart indoor lighting systems, since the lighting system is nonlinear and time variant. In this paper, a smart and power efficient control method is developed in order to determine luminaires dimming level in an indoor environment with multiple work zones. A positive point of the proposed control method is that photodetectors are placed at the work zones which increase the accuracy. Besides, different number of photodetectors can be placed at work zones in the proposed control method, since work zones may have different dimensions and also accuracy levels may differ. The control method takes the advantages of learning method to avoid complexity and also increase system reliability. The system can properly work with daylight variation during the daytime. Case studies are implemented in DIALux and the control method is evaluated in MATLAB. It is shown that the error for static condition is below 1% and for dynamic condition which daylight varies during daytime is increases to 5.6%

MyoRing Implantation with and without Corneal Collagen Crosslinking for the Management of Keratoconus

Purpose: To evaluate the safety and efficacy of femtosecond laser-assisted MyoRing implantation with concurrent corneal collagen crosslinking (CXL) compared to MyoRing alone for the treatment of progressive keratoconus. Methods: A total of 60 patients were enrolled in this randomized controlled trial. The patients were randomly allocated into two groups. In the first group, MyoRing was implanted, while in the second, it was inserted in the corneal stroma using the same technique, along with simultaneous CXL. Visual, refractive, topographic, and abberometric outcomes were measured preoperatively and at every postoperative visit. Results: Data of 47 patients were available at the end of the study; 28 in the MyoRing group and 19 in the MyoRing + CXL group. The mean uncorrected distance visual acuity (UDVA) improved from 0.79 ± 0.39 logMAR to 0.52 ± 0.31 logMAR (P < 0.05) in the MyoRing + CXL group and from 0.65 ± 0.38 logMAR to 0.62 ± 0.23 logMAR (P = 0.70) in the MyoRing group. CDVA changed from 0.33 ± 0.19 logMAR to 0.25 ± 0.16 logMAR (P = 0.10) in the MyoRing + CXL group and 0.32 ± 0.22 logMAR to 0.33 ± 0.17 logMAR (P > 0.5) in the MyoRing group. The mean keratometry (Km) decreased from 47.5 ± 2.7 D to 43.8 ± 3.2 D (P < 0.001) in the MyoRing group and 49.3 ± 3.4 D to 45.1 ± 3.0 D (P < 0.001) in the MyoRing + CXL group. Besides, horizontal coma was significantly lower in the MyoRing + CXL group (P = 0.022). Conclusion: MyoRing insertion combined with CXL is a safe and effective method for the treatment of keratoconus. The visual and topographic outcomes were comparable to that for MyoRing insertion after 10 months; however, horizontal coma was significantly lower in the MyoRing + CXL group

Zone Based Control Methodology of Smart Indoor Lighting Systems Using Feedforward Neural Networks

A smart, accurate, and energy efficient control strategy to adjust dimming level of luminaires in an indoor environment is proposed in this paper. The control block in lighting system is nonlinear and time variant, since multiple reflections of objects and daylight variation are related to daytime and they can directly affect the system. According to the complexity of equations which model the lighting system, a control system based on Neural Network (NN) and learning machine is developed. By considering each zone as an independent structure, occupancy in each zone is added. In addition, photodetectors are placed at the work zones and hence increasing the accuracy. The occupancy condition for other zones in the environment are considered as bias to the inputs of the system. Therefore, multiple reflections in the environment are considered in the design of the proposed control method. Accuracy and system performance is improved by separation of control block for each zone as an autonomous control unit, whereas complexity of the system is reduced. The proposed design is evaluated in test beds developed using DIALux and MATLAB. The mean error varies according to the effect of zones on each other. The method is suitable for indoor environment that zones does not have common luminaires. The mean error in the case study that is not proper for the method does not exceed 20%. Although, the error seems to be high but compared to the methods that have ceiling mount sensors is accurate and power and power efficient. Besides, the case with zones that has separated luminaires the mean error is less than 5%

Analysis and design of defected ground structure for EMC improvement in mixed-signal transceiver modules

In this research, the return path discontinuity (RPD), located under the power amplifier (PA) substrate, of X-band transceiver module (Base), mounted on a four-layer printed circuit board (PCB), is investigated to improve the signal integrity by reducing the difference in the reference potential. This study is performed by initially employing the wirebond method, through the assessment of both numbers and sizes of bondwires by advanced design system (ADS). Six bondwires of 25 µm are added, producing an improvement of 6.82 dB for the reflection coefficient and 1.19 dB for the isolation and insertion loss. For further improvement, spiral shape defected ground structure (DGS) is implemented in the inner ground layer (layer 2) without using bond wires. The DGS simulation results illustrate an improvement of 3 dB for S11 and 0.6 dB for S12. To improve the electromagnetic compatibility (EMC), the authors propose combination and integration of both wirebond and DGS methods, called wirebond–DGS method, which results in an improvement of 11.86 dB for S11, 1.34 dB for S12 and S21, and 12.03 dB for S22. Finally, the wirebond–DGS RF module was fabricated and the measurement results exhibit an improvement of 8.07 dB for S11 and 9.39 dB for S22 in comparison with the fabricated Base module. In addition, 0.53 dB improvement for both S12 and S21 is also achieved

An Efficient Method for Extraction of Transfer Function of H-Tree Clock Distribution Networks

An efficient derivation methodology is proposed for extracting general transfer function of H-Tree clock distribution network. This is an accurate, fast and simple method to determine transfer function of any balanced tree structures with branching factor of two. This approach is caused a highly accurate and simple method to evaluate the 50 % propagation delay at output nodes of the binary balanced trees

A 4.35-mW +22-dBm IIP3 continuously tunable channel select filter for WLAN/WiMax receivers in 90-nm CMOS

A low-power high linearity CMOS G(m)-C channel select filter for WLAN/WiMax receivers in 90-nm CMOS technology is presented. To reduce power consumption a biquad cell with simple architecture and few devices is used. A simple but efficient technique is also used to improve the linearity of the filter without increasing its power consumption. The cutoff frequency of the sixth order Butterworth low-pass filter can be tuned from 8.1 to 13.5 MHz for WLAN and WiMax applications. The measurement results show an in-band IIP3 of +22 dBm and an input referred noise of 75 nV/root Hz at a power consumption of 4.35 mW from a 1-V supply. The differential filter occupies a chip area of 0.239 mm(2) excluding pads