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components of input current, 1 U is effective value of fundamental component of input AC voltage, is deformation factor of input current, 1  is the angel between the input AC voltage and fundamental component of the input current. It is clear that the power factor PF is determined by  and 1  . The bigger the 1  , the bigger the reactive power is, the bigger the wastage of conductive line wire and transformer is. The smaller the  , the bigger the input current harmonics of is, which will cause current distortion, produce pollution to electric grid, and even damage the electric equipments if condition is serious.

Background and Objective: Citrus grandis ‘Tomentosa’, as the fruit epicarp of C. grandis ‘Tomentosa’ or C. grandis (L.) Osbeck, is widely used in health food and medicine. Actually, based on our survey results, there are also rich essential oils with bioativities in leaves, but the chemical compounds in this part and relevant pharmacological activities have never been studied systematically yet. Therefore, this study was to preliminarily decipher the pharmacological activities and mechanisms of the essential oil in leaves of C. grandis ‘Tomentosa’ by an integrated network pharmacology approach. Methods: Essential oil compositions from leaves of C. grandis ‘Tomentosa’ were identified using GC-MS/MS. And then the targets of these oil compositions were predicted and screened from TCMSP, SwissTargetPrediction, STITCH and SEA databases. STRING database was used to construct the protein-protein interaction networks, and the eligible protein targets were input into WebGestalt 2019 to carry out GO enrichment and KEGG pathway enrichment analysis. Based on the potential targets, disease enrichment information was obtained by TTD databases. Cytoscape software was used to construct the component-target-disease network diagrams. Results: Finally, 61 essential oil chemical components were identified by GC-MS/MS, which correspond to 679 potential targets. Biological function analysis showed that there were 12, 19, and 12 GO entries related to biological processes, cell components and molecular functions, respectively. 43 KEGG pathways were identified, of which the most significant categories were terpenoid backbone biosynthesis, TNF signaling pathway and leishmaniasis. The component-target-disease network diagram revealed that the essential oil compositions in leaves of C. grandis ‘Tomentosa’ could treat tumors, immune diseases, neurodegenerative diseases and respiratory diseases, which were highly related to CHRM1, PTGS2, CASP3, MAP2K1 and CDC25B.Conclusion: This study may provide a new insight into C. grandis ‘Tomentosa’ or C. grandis (L.) Osbeck and may provide useful information for future utilization and development.

A large eddy simulation (LES) model was used to examine the wind-driven cross ventilation of gable-roof greenhouses containing vegetation. The obstruction of air flow by vegetation was described by a porous drag model in the numerical model, and the simulation results were validated using wind tunnel experiments. The numerical model was then utilised to inspect the influences of vegetation and greenhouse length (in the wind direction) on the ventilation rate. The results revealed that the diminishing effects of the vegetation, insect screen and internal friction on the ventilation rate can all be quantified by a physical-based resistance model. The driving force (the difference between windward and leeward pressures) of long, multi-span greenhouses was found to be less than that of a short, single-span greenhouse leading to a lower ventilation rate. The resistance factor of the vegetation and the insect screen depends on their porosity, while the resistance factor of the internal friction increased as the greenhouse length increased. In addition, the internal friction of multi-span greenhouses should be considered when the length of the greenhouse was greater than six times the greenhouse height.

A traditional zoom system is composed of several elements moving relatively toward other components to achieve zooming. Unlike tradition system, an electrically control zoom system with liquid crystal (LC) lenses is demonstrated in this paper. To achieve zooming, we apply two LC lenses whose optical power is controlled by voltage to replace two moving lenses in traditional zoom system. The mechanism of zoom system is to use two LC lenses to form a simple zoom system. We found that with such spherical electrodes, we could operate LC lens at voltage range from 31V to 53 V for 3X tunability in optical power. For each LC lens, we use concave spherical electrode which provide lower operating voltage and great tunability in optical power, respectively. For such operating voltage and compact size, this zoom system with zoom ratio approximate 3:1 could be applied to mobile phone, camera and other applications.

Peat is known as problematic ground with low bearing capacity and extensively high compressibility. Ordinary Portland cement (OPC) and lime were usually used to tackle unfavourable characteristics of peat by improving it with its cementation effect. However, little was known of the effect of bio-cementation towards peat improvement. Bio-cementation or commonly known as Microbial-induced calcite precipitation (MICP) has been recently introduced as a ground improvement alternative for geotechnical engineering application. MICP performed by utilising metabolic pathways of non-pathogenic urealytic bacteria that precipitates calcium carbonate (CaCO3) crystal as cementation binder that seal soil particles together increasing soil strength. MICP of inorganic soil was extensively explored, and only limited was done for organic soil. This study explores on the effect of different surcharge preloading of 18kPa, 36kPa and 48kPa towards Microbial-Induced Calcite Precipitation (MICP) treatment of tropical peat. Fibrous peat studied were obtained from Miri, Sarawak and cured under a submerged condition with different vertical preload for seven days. Laboratory study including unconfined compression test, quantification of carbonates precipitated, and moisture content of stabilised specimens was observed to evaluate the performance of stabilisation effort. Unconfined compressive strength (UCS) of treated specimens was observed to be higher than untreated specimens with the highest increase of UCS up to 469%. However, CaCO3 precipitation amount for this study was observed to decrease with increasing surcharge preload.

This paper presents the design of a bilateral tracing intelligent car based on photoelectric sensors. The control system selects the 16-bit MC9S12XS128 microprocessor as the core controller; employs laser tube and receiving tube to detect the location and movement direction; applies fuzzy self-adaptive PD controller to control the servos; makes use of photoelectric encoder to examine the cars speed. Experimental results indicate that the intelligent car can run along the track steadily and rapidly.

This letter proposes a dual-band divide-by-2 transformer-coupled quadrature injection-locked frequency divider (QILFD).The QILFD is composed of a transformer-coupled quadrature voltage controlled oscillator and two injection MOSFETs. The CMOS QILFD has been implemented with the Taiwan Semiconductor Manufacture Company (TSMC) 0.18 μm CMOS technology, and the core power consumption is 3.997 mW at the supply voltage of 0.7 V. The tank impedance of the QILFD shows a dual resonance behavior, which leads to a dual-band locking range at a fixed bias condition. At the injection input power of 3 dBm, the low-band and high-band divide-by-2 locking ranges are from 6.90 to 8.56 GHz and 9.52 to 12.10 GHz, respectively. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26074

In this paper, a liquid crystal microlens array with a curved electrode is designed and fabricated. The fabrication process consists of two parts: fabricating the microlens array and assembling the liquid crystal cell. The first process utilizes the hydrophilic confinement effect, an inkjet printer, and the replication process to fabricate a microlens array on a glass substrate. A transparent, organic, conductive poly (3, 4-ethylenedioxythiophene): poly (styrenesulfonate) (PEDOT:PSS) is spin-coated on the microlens array as a curved electrode, and the microlens array is further flattened by SU-8 photoresist. It is then assembled with indium tin oxide glass. Interference patterns for the liquid crystal microlens array are measured and agree well with theoretical calculations. From interference patterns, the focusing power range is measured to be from −47.28 to −331 diopters under 10 V, which corresponds to focal length from −2.12 cm to −0.3 cm at 532 nm wavelength. This technology could be useful for optical zoom systems or focus-tunable lens applications.

A TW (Tera Watt) laser system based on Ti:sapphire mainly for the Tsinghua Thomson scattering X-ray light source (TTX) is being built. Both UV (ultraviolet) laser pulse for driving the photocathode radio-frequency (RF) gun and the IR (infrared) laser pulse as the electron-beam-scattered-light are provided by the system. Efforts have also been made in laser pulse shaping and laser beam transport to optimize the high-brightness electron beam production by the photocathode RF gun.

On the base of the heat release rate and the output of smoke in a closed cabin' fire, the water mist model is founded with the zones model and the characteristic of water mist. The relation between temperature / pressure and time is solved by energy equation, mass equation, and gas equation; At the same time, the principle that fire could be put out by water mist is brought forward. At last, the result of a example is tested same as the real fire, and the rule is attained that gas temperature and air pressure are changed by water mist, it will help people know the fire under water mist, and help people put out a fire and succor themselves.

Linearity of VCO directly impacts on the range resolution of LFMCW radar. So, linearity correction is usually adoptted in practical applications. Because VCO's linearity correction is a highly nonlinearity controlled object, which modern control method is effective with difficulty. Therefor, a system of linearity correction based on fuzzy control is proposed in this paper. The simulation results show that fuzzy controller performed well in linearity correction of VCO.

One of key techniques for high precision VCO and high resolution LFMCW radar is linearity correction, and the accuracy of linearity correction is directly determined by the precision of nonlinearity detection results. Therefor, this paper proposes a method of rapid linearity detection of LFMCW radar. First, estimate and correct the instantaneous phase. Then, fit a straight line for the instantaneous phase of difference frequency signal. Finally, estimate the instantaneous Frequency-Modulation rate of FM signal. Simulation results show that, the proposed method can detect VCO linearity more effectively.

The basic principle of FM-CW radar level gauge is analyzed briefly. A method of estimating its frequency difference is proposed based on 2/sup 19/-point discrete Fourier transform (DFT) and interpolation. The frequency estimation includes two steps, called coarse-estimation and fine-estimation, both of which are based on 2/sup 19/-point DFT. As a result, the method is applicable to estimate a frequency under serious noise background where signal-noise-ratio (SNR) is as low as -32 dB. Simulation results show that the method is adaptive to noise and has high computational accuracy and small computation necessary, which makes it suitable for an on-line use for frequency-estimation.