Wyniki wyszukiwania - BazTech

1

Ship trajectory tracking control system design based on sliding mode control algorithm

Liu Y., Bu R., Gao X.

Polish Maritime Research

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2018

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nr 3

26--34

EN

The paper reports the design and tests of the planar autopilot navigation system in the three-degree-of-freedom (3-DOF) plane (surge, sway and yaw) for a ship. The aim of the tests was to check the improved maneuverability of the ship in open waters using the improved nonlinear control algorithm, developed based on the sliding mode control theory for the ship-trajectory tracking problem of under-actuated ships with static constraints, actuator saturation, and parametric uncertainties. With the integration of the simple increment feedback control law, the dynamic control strategy was developed to fulfill the under-actuated tracking and stabilization objectives. In addition, the LOS (line of sight) guidance system was applied to control the motion path, whereas the sliding mode controller was used to emulate the rudder angle and propeller rotational speed control. Firstly, simulation tests were performed to verify the validity of the basic model and the tracking control algorithm. Subsequently, full scale maneuverability tests were done with a novel container ship, equipped with trajectory tracking control and sliding mode controller algorithm, to check the dynamic stability performance of the ship. The results of the theoretical and numerical simulation on a training ship verify the invariability and excellent robustness of the proposed controller, which: effectively eliminates system chattering, solves the problem of lateral drift of the ship, and maintains the following of the trajectory while simultaneously achieving global stability and robustness.

2

Focusing of linearly polarized helico-conical Lorentz beam with sine-azimuthal variation wavefront

Bao Y., Lan J., Miao Y., Zhang D., Gao X.

Optica Applicata

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2018

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Vol. 48, nr 3

373--387

EN

In this article a theoretical research is described into focusing of a linearly polarized helico-conical Lorentz beam with a sine-azimuthal variation wavefront. The simulation results show the vortex charge on the axis, which has an obvious modulation effect on the focal modes of the Lorenz beam under certain beam parameters and phase parameters. Both the phase parameter and the vortex charge are zero, the focal spot appears round. The focal spot is symmetric about y axis when the charge is 0 and the phase parameter is adjusted. And the focal evolution patterns vary remarkably under different beam parameters and the phase parameters. In the process of focus evolution, there appears some novel focal patterns, such as a circle, a “T”, a butterfly, a small running humanoid, a whale tail, a flower of four leaves, a serpentine, a goldfish, a Chinese knot and an octopus, which indicates that the focus mode of the optical vortex Lorentz beam can be altered by changing the phase parameters and vortex charge.

3

Regional geographies of land transport networks in the Pearl River Delta mega-region, China: A longitudinal analysis

Gao X., Li T.

Journal of Sustainable Development of Transport and Logistics

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2018

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Vol. 3, No. 1

37--52

EN

This paper uses network-based efficiency measures to evaluate the efficiency implications of the evolution of the transport network in the Pearl River Delta (PRD) over the period 1988-2008. The network-based efficiency measures consider the relative ease of access between cities in terms of weighted relative travel cost. The results indicate that the spatial patterns of network efficiency are different from ‘core-periphery’ pattern derived from classical accessibility indicators. This implies that there are low network efficiency cities and high network efficiency cities in core and peripheral regions at the same time. In the first stage (1988-1998), the efficiency contour shows a ‘corridor’ pattern along the GuangShen traffic corridor between Guangzhou and Shenzhen in the eastern side of the Pearl estuary; in the following decade (1998-2008), with large-scale infrastructural developments, the spatial pattern has changed from a north-south corridor to an east-west contiguous distribution pattern. By 2008, the mean network efficiency value indicates that the efficiency levels within the PRD as a whole are tending towards optimal levels. We conclude by suggesting ways to promote the urban economic development based on the relationship between the network efficiency and per capita GDP.

4

Tensile-tensile Fatigue Behavior of Multi-axial Warp-knitted Reinforced Composite

Gao X., Tao N., Chen S., Wang L., Wu W.

Fibres & Textiles in Eastern Europe

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2018

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Vol. 26, no. 1 (127)

73--80

EN

An experimental study was carried out on the fatigue behaviour of multi-axial warp-knitted fabric composites. Composite samples reinforced with multi-axial warp-knitted fabric/matrix were manufactured by the vacuum-assisted resin transfer moulding method. Tensile-tensile fatigue cycling was carried out at different load levels, and S-N curves, tensile stress-strain curve and stiffness degradation of the multi-axial composite samples were obtained. Finally post-fatigue tensile tests were done at a stress level of 75%, at the stages of 1/3N and 2/3N, and the equivalent residual strength and stiffness degradation were obtained.

PL

Dokonano oceny właściwości mechanicznych i zmęczeniowych kompozytowych dzianin wieloosiowych. Kompozyty wzmocnione dzianiną wieloosiową wytworzono przy zastosowaniu próżniowej metody formowania. Dokonano oceny zmęczenia materiału i właściwości wytrzymałościowych przy różnych poziomach obciążenia. Przedstawiono krzywe S-N, krzywą naprężenie-odkształcenie i degradację sztywności wieloosiowych próbek kompozytowych. Wykonano również testy zmęczenia materiału przy poziomie naprężenia 75%, w etapach 1/3N i 2/3N. Omówiono równoważną wytrzymałość szczątkową i degradację sztywności kompozytowych dzianin wieloosiowych.

5

Experimental and Numerical Simulation of the Tensile Behaviour of a Biaxial Warp-knitted Composite

Gao X., Yang X., Li D., Li Y.

Fibres & Textiles in Eastern Europe

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2018

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Vol. 26, no. 6 (132)

71--76

EN

In this paper a composite reinforced with biaxial warp-knitted fabric and epoxy resin was manufactured by applying vacuum assisted resin transfer moldings (VARTM). The quasi-static tensile behaviour was experimentally tested in 0° and 90° directions, respectively. A finite element model of biaxial warp-knitted composites was developed on a meso-scale. The tensile behaviour of the composites was numerical simulated and compared with the experimental results. It showed that there is an approximate agreement between experimental and numerical results. There are maximum errors sum of squares of 14.52% and 33.29%. The finite element model of biaxial warp-knitted composites has higher accuracy, which can be used to study the static and dynamic mechanical properties.

PL

Wykonano kompozyt wzmocniony dwuosiową dzianiną osnowową i żywicą epoksydową z zastosowaniem próżniowego przenoszenia żywicy (VARTM). Quasi-statyczne właściwości rozciągania badano doświadczalnie odpowiednio w kierunkach 0° i 90°. Opracowano model skończonych elementów dwuosiowych kompozytów z dzianinami. Dokonano symulacji numerycznej zachowania kompozytów podczas rozciągania, a następnie porównano wyniki teoretyczne z wynikami eksperymentalnymi. Wykazano, że istnieje przybliżona zgodność między wynikami eksperymentalnymi i liczbowymi. Stwierdzono, że błędy maksymalne błędy kształtują się na poziomie 14,52% i 33,29%. Zaprezentowany model elementów skończonych ma wysoką dokładność i można go wykorzystać do badania statycznych i dynamicznych właściwości mechanicznych kompozytów.

6

Analysis of the Twist Structure in Self-twist Yarn

Cui H., Gao X., Gao D., Lin H.

Fibres & Textiles in Eastern Europe

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2017

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Vol. 25, no. 2 (122)

53--56

EN

This paper mainly discussed the twist structure and property difference between in-phase self-twist yarn and phased self-twist yarn. There are three kinds of zones along the yarn: the twist-twist zone, twist-notwist zone and notwist-notwist zone in one cycle length of self-twist yarn. The existence of the phase difference makes the length of the notwist-notwist zone decrease. When the size of the phase difference (value c)is closer to or equal to the length of the zero zone(value b), the minimum length of the notwist-notwist zone will be obtained so that the best properties of self-0twist yarn can be achieved. The result for in-phase and phased self-twist yarn shows that the above conclusion is correct.

PL

W artykule omówiono strukturę skrętu i właściwości przędz samo-skrętnych. W przędzach samo-skrętnych istnieje strefa o zazwyczaj słabym skręcie pomiędzy strefami włókien skręconych i nieskręconych. Istnienie różnicy faz w różnych typach przędz samo-skrętnych powoduje zmniejszenie długości strefy włókien nieskręconych. Minimalna długość tej strefy zostanie osiągnięta, gdy wielkość różnicy faz jest większa lub równa długości strefy zerowej, pozwala to na osiągnięcie jak najlepszych właściwości przędz samo-skrętnych.

7

An Experimental Study Of The Compression Properties Of Polyurethane-Based Warp-Knitted Spacer Fabric Composites

Chen S., Zhang X., Chen H., Gao X.

Autex Research Journal

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2017

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Vol. 17, no. 3

199--205

EN

The present work has reported the compression properties of polyurethane-based warp-knitted spacer fabric composites (PWSF). In order to investigate the effect of structural parameters of fabric on the compression performance of composites, a series of warp-knitted spacer fabrics (WSF) with different structural parameters including spacer yarn inclination angle, thickness, fineness of spacer yarns, and outer layer structure have been involved. The produced composites have been characterized for compression properties. The energy-absorption performance during the compression process has been determined as a function of the efficiency and the compression stress obtained from compression tests. The results show that the composites based on spacer fabrics having smaller spacer yarns inclination angle, higher fabric thickness, finer spacer yarn, and larger mesh in outer layers perform better with respect to energy-absorption properties at lower stress level, whereas at higher stress level, the best energy-absorption abilities are obtained in case of spacer fabrics constructed of larger spacer yarn inclination angle, lower fabric thickness, coarser spacer yarn, and smaller mesh in surface layers.

8

Ship Behavior Analysis for Real Operating of Container Ships Using AIS Data

Gao X., Makino H., Furusho M.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2016

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Vol. 10, no. 2

213--220

EN

The aim of this paper is to understand the real activity and operating situation of container ships in order to improve navigation efficiency. The study focused on the navigation for an entire ship voyage to understand the real activity of container ships using the historical ship navigation based on Automatic Identification System (AIS) data, which is possible so as to unveil the characteristics of real ship activity. The analysis considers ship voyages in the Seto Inland Sea and its oceanic waters, which are the primary traffic routes for container transportation particularly for China, Japan, and South Korea. The results of this study can be used to improve the efficiency of container ships and develop a smoother maritime transportation.

9

Nonlinear inverse solution by the look-up table method for Risley-prism-based scanner

Li A., Sun W., Gao X.

Optica Applicata

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2016

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Vol. 46, nr 4

501--515

EN

A pair of rotation Risley prisms can perform superior optical pointing and tracking functions with large visual field and high accuracy. Crucial to the function implementation are the nonlinear inverse solutions to the double-prism orientation angles for tracking a given target trajectory. In the paper, a novel look-up table method is proposed to solve this problem. Because there are two groups of solutions to the rotation angles achieved from an arbitrary target point, a "jump" phenomenon occurs and generates the discontinuous curves of multi-group rotation angle solutions. According to the mapping relation between the coordinate values of the target point and the corresponding rotation angles of two prisms, we can establish the continuous solution curves by adding constraints and employing an optimization algorithm. Experimental results validate the obtained inverse solutions applicable to scan a trajectory close to the given one within an error threshold. The proposed look-up table method can provide foundation for the continuous control of the Risley-prism-based scanner in its inverse applications.Keywords: Risley prism, look-up table method, inverse solution, scanner.

10

Antibiotics in WWTP discharge into the Chaobai River, Beijing

Zhang C., Wang L., Gao X., He X.

Archives of Environmental Protection

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2016

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Vol. 42, no. 4

48--57

EN

22 representative antibiotics, including 8 quinolones (QNs), 9 sulfonamides (SAs), and 5 macrolides (MCs) were selected to investigate their occurrence and removal efficiencies in a Wastewater Treatment Plant (WWTP) and their distribution in the receiving water of the Chaobai River in Beijing, China. Water quality monitoring was performed in an integrated way at different selected points in the WWTP to explore the potential mechanism of antibiotics removal during wastewater treatment. Water quality of the Chaobai River wa s also analyzed to examine environmental distribution in a river ecosystem. The results showed that within all the 22 compounds examined, 10 antibiotics were quantifi ed in wastewater influent, 10 in effluent, and 7 in river. Sulfadiazine (SDZ, 396 ng/L) and Sulfamethazine (SMZ, 382 ng/L) were the dominating antibiotics in the influent. Both the conventional treatment and advanced Biological Aerated Filter (BAF) system was important for the removal of antibiotics from the wastewater. And the concentrations of selected antibiotics were ranged from 0–41.8 ng/L in the effluent-receiving river. Despite the fact that the concentrations were reduced more than 50% compared to effluent concentrations, WWTP discharge was still regarded as a dominant point-source input of antibiotics into the Chaobai River.

11

Analysis of the Creep Properties of Nonwoven Fabric with Mechanical Models

Gao X., Chen H., Sun S.

Fibres & Textiles in Eastern Europe

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2015

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Vol. 23, no. 1 (109)

72--76

EN

Since nonwoven fabric is widely used in the application of high performance geotextiles, its creep behaviour is essential to be evaluated. In this paper, the creep response of nonwven fabric was studied by using four mechanical models including the one-term generalised Kelvin model, Burger’s model, two-term generalised Kelvin model and Zurek’s model. To verify the feasibility of the models, creep experiments for nonwoven fabric were conducted, and the data were fitted by the four models, respectively, to obtain their parameter values using the Marquardt algorithm for nonlinear regression. When comparing the experimental creep curves with those fitted from the mechanical models, it is obvious that the experimental data was best fitted by Burger’s model. Also, since the residual sum of squares is far less than that of the GK (n = 1) and GK (n = 2) model and the squares of the correlation coefficient are near to unity, it can be concluded that Burger’s model is suitable to describe the creep behaviour of nonwoven fabric. Therefore the viscoelastic model verified can be adopted to predict the creep elongation of nonwoven fabrics.

PL

W artykule zaprezentowano możliwość zastosowania modeli reologicznych do modelowania zjawiska pełzania włóknin. Włókniny i geowłókniny znajdują szerokie zastosowanie w inżynierii lądowej. Zjawiska jakie zachodzą podczas użytkowania geowłóknin są złożone. Jednym ze zjawisk pojawiających się podczas użytkowania jest poddawanie włókniny i geowłókniny stałym napięciom wynikającym ze zjawiska pełzania. Zastosowano trzy rodzaje modeli reologicznych w oparciu o modele Kelvina, Burgersa i uogólnionego modelu Kelvina. Wygenerowane modele teoretyczne zostały utworzone w celu przewidywania zjawiska pełzania. Adekwatność modeli reologicznych przeprowadzono w oparciu o metodę najmniejszych kwadratów dla estymacji parametrów w nieliniowych modelach regresji Levenberga - Marquardta. Zastosowano modele, które można dopasowywać przy pomocy estymacji metodą najmniejszych kwadratów dowolnej funkcji straty określonej przez użytkownika. Zastosowano funkcję straty do wyboru procedury estymacji, tak że praktycznie we wszystkich przypadkach otrzymano stabilne oceny parametrów modeli. Najlepsze efekty otrzymano przy zastosowaniu modelu Burgersa, który to może być użyty do przewidywania pełzania włókniny w obiektach inżynierskich.

12

Finite Element Modelling for Tensile Behaviour of Thermally Bonded Nonwoven Fabric

Gao X., Wang L.

Autex Research Journal

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2015

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Vol. 15, no. 1

48--53

EN

A nonwoven fabric has been widely used in geotextile engineering in recent years; its tensile strength is an important behaviour. Since the fibre distributions in nonwoven fabrics are random and discontinuous, the unit-cell model of a nonwoven fabric cannot be developed to simulate its tensile behaviour. This article presents our research on using finite element method (FEM) to study the tensile behaviour of a nonwoven fabric in macro-scale based on the classical laminate composite theory. The laminate orientation was considered with orientation distribution function of fibres, which has been obtained by analysing the data acquired from scanning electron microscopy with Hough Transform. The FE model of a nonwoven fabric was developed using ABAQUS software; the required engineering constants of a nonwoven fabric were obtained from experimental data. Finally, the nonwoven specimens were stretched along with machine direction and cross direction. The experimental stress-strain curves were compared with the results of FE simulations. The approximate agreement proves the validity of an FE model, which could be used to precisely simulate the stress relaxation, strain creep, bending and shear property of a nonwoven fabric.

13

Foliar responses of Abie fargesii Franch. To altitude in the Taibai Mts, China

Xu P., Zhang X., Zhao C., Chen L., Gao X., Yao B., Deng J., Deng Y.

Polish Journal of Ecology

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2014

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Vol. 62, nr 3

479--492

EN

Physiological and ecological adaptations of altitudinal gradients reveal alpine plants’ ecological and evolutionary responses to environmental changes. Here we quantitatively investigated the variation in the foliar physiological and morphological traits of alpine tree species (Abies fargesii) along the altitudinal gradient in the Taibai Mountains, China. We collected the needle samples of Taibai fir (A. fargesii) from seven sites at altitudes of 2550, 2650, 2750, 2850, 2950, 3050 and 3150 m, respectively, and measured the 12 foliar physiological and morphological traits. Each set of needle sample (100 needles) was randomly selected from the upper- third of A. fargesii canopies. The results showed that leaf mass per unit area (LMA), stable carbon isotope composition (δ13C), stomatal rows (SR), leaf carbon concentration per unit area (Carea), leaf nitrogen concentration per unit leaf mass (Nmass) and area (Narea) linearly increase significantly while stomatal density (SD), number of stomata per unit nitrogen concentration (St/N) and per unit leaf mass (St/LM) decrease with the altitudes raise. Moreover, all measured traits presented both strong correlations and significantly linear relationships with the main climate factors such as the mean temperature, rainfall and relative humidity during the growing season as well as the altitudes, except for leaf free water concentration (LWC), leaf carbon concentration per unit leaf mass (Cmass) and C: N ratio. The patterns of foliar traits in response to altitudes imply that the alpine plants need higher cost (e.g. higher nutrient concentration) to adapt to the harsher environments along altitudinal gradient. Moreover, our results show that the variation patterns of the leaf traits for A. fargesii plants should be driven by the interactions of multi-climate factors because the abiotic factors that directly influence the growth of plants covary with the increasing altitudes.

14

The Preparation of Soluble Cellouronic Acid Sodium Salt by 4-Acetamide-TEMPO Mediated Oxidation of Ultrasound-Pretreated Parenchyma Cellulose from Bagasse Pith

Gao X., Chen K., Zhang H., Peng L.

Archives of Acoustics

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2014

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Vol. 39, No. 2

267--275

EN

The parenchyma cellulose isolated from bagasse pith was used as an alternative resource for preparation of water-soluble cellouronic acid sodium salt (CAS). The influence of ultrasound treatment on the cellulose was investigated for obtaining CAS by regioselective oxidization using 4-acetamide-TEMPO and NaClO with NaClO2 as a primary oxidant in an aqueous buffer at pH 6.0. The yield, carboxylate content and polymerization degree (DP) of CAS were measured as a function of ultrasonic power, agitating time and cellulose consistency by an orthogonal test. The ultrasound-treated conditions were further improved by discussion of ultrasonic power, the most important factor influencing the yield and DP. An optimized CAS yield of 72.9% with DP value (DPv) of 212 was found when the ultrasonic strength is 550 W, agitating time is 3 h and cellulose consistency is 2.0%. The oxidation reactivity of cellulose was improved by ultrasonic irradiation, whereas no significant changes in crystallinity of cellulose were measured after ultrasonic treatment. Moreover, the ultrasound treatment has a greater effect on yielding CAS from parenchyma cellulose than from bagasse fibrous’ one. The CAS was further characterized by Fourier transform infrared spectroscopy (FT-IR) and Scanning electron microscopy (SEM).

15

Workflow Region Recognition Algorithm and Its Time Complexity

Gao X., Wang X., Yang M., Liu Y.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

184--186

EN

Based on polychromatic sets theory, a new workflow model – special net structure model (SNS model) is proposed, and a concept of workflow region is defined. And then, the recognition algorithm of workflow region is presented and its time complexity is analyzed quantitatively. The compound workflow SNS model can be reduced level by level from inner to outer by invoking the recognition algorithm of workflow region. This recognition algorithm is executed only once for a lot of workflow dynamic changes. Therefore, the computing complexity is feasible and acceptable.

PL

W artykule przedstawiono propozycję nowego modelu pracy strumieniowej SNS (ang. Special Net Structure), opartego na teorii ustawień polichromatycznych oraz koncepcję obszaru pracy strumieniowej. Przeprowadzono analizę działania algorytmu rozpoznawania regionu pracy strumieniowej, jego skuteczności i stopnia komplikacji. Uzyskane wyniki wskazują na jego pełną wykonalność.

16

Impact of Protective Relays on Voltage Sag Index

Gao X., Liu Y., Wang C.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 5

59-62

EN

This paper provides the probability-assessment analysis on the characteristic value of the voltage sag by using Monte Carlo stochastic modelling method to stimulate the randomness of the short circuit fault. Furthermore, this article simulates the influence of the protection devices on the voltage sag to ensure the authenticity and the referential reliability. A system with inverse-time protection devices equipped on each lines which could coordinate together are designed to cut off the short-circuit fault. The voltage sag of the designed system is evaluated by the pre-and post system average RMS variation frequency index, and the voltage sag index is compared with the ITIC curves.The simulation results demonstrated that the inverse-curve relay protection equipments are well-coordinated, and the severity and the range of the voltage sag are influenced by the cooperation of the equipped inverse time protection devices.

PL

W artykule przedstawiono metodę szacowania prawdopodobieństwa wystąpienia zapadu napięcia na podstawie analizy jego charakterystycznych parametrów zamodelowanych metodą Monte Carlo. Ponad to, w celu weryfikacji skuteczności, dokonano symulacji wpływu urządzeń ochronnych na zapady napięcia. Zaprojektowano także system z urządzeniami umożliwiającymi odizolowanie zwarcia w obwodzie od reszty sieci. Wyznaczono współczynnik częstotliwościowy zmienności wartości średniej RMS zapadów napięcia w proponowanym układzie, który następnie porównano z krzywymi ITIC. Przeprowadzone badania symulacyjne potwierdziły skuteczność i szybkość działania systemu.

17

Optical gradient force of cosh-Gaussian with sine-azimuthal and half-space phase modulation

Fu R., Gao X., Shen H., Xin Q, Lu X., Guo L.

Optica Applicata

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2013

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Vol. 43, nr 4

719--730

EN

The optical gradient force distributions in focal plane of cosh-Gaussian beams with sine-azimuthal variation wavefront and half space phase modulation were investigated. Results show that optical gradient force distributions can be affected considerably by the phase retardation of half-space phase modulation, of a phase parameter that indicates the phase change frequency on an increasing azimuthal angle, and beam parameters in cosh terms of the incident beams. Many gradient force patterns occur, including cross-shape, multiple optical trap arrays, multiple-trap wheel, and many kinds of gradient force lines and curves. Symmetry of the whole gradient force pattern can also be altered remarkably. Above results may find wide applications in optical trapping systems.

18

Focus shaping of the radially polarized Bessel–Gauss beam with a sine-azimuthal variation wavefront

Gao X, Zhang D., Mei T., Fu R., Zhuang S.

Optica Applicata

|

2013

|

Vol. 43, nr 3

567--582

EN

Focusing properties of the radially polarized Bessel–Gauss beam with a sine-azimuthal variation wavefront was investigated by the vector diffraction theory. The wavefront distribution is the sine function of the azimuthal angle with one phase parameter that indicates the phase change frequency. Results show that the focal pattern can be altered by the phase parameter, and many novel focal patterns may occur, such as multiple dark-foci focal pattern, crescent shape, and wheel shape. For case of a higher phase beam, the whole focal pattern turns on a symmetric wheel shape with multiple reduplicate intensity elements. When the phase parameter is an odd number, the number of reduplicate elements equals the phase parameter, while when the phase parameter is an even number, the number of reduplicate elements is two times the phase parameter. In addition, the effect of the phase parameter on the focal pattern is more considerable than that of the beam parameter under low numerical aperture. Under higher numerical aperture, the effect of the beam parameter on the focal pattern gets stronger.

19

Using LC-MS/MS to study dauricine pharmacokinetics and determine its bioavailability following administration in different routes

Gao X., Jiang X., Wang L.

Acta Chromatographica

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2013

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Vol. 25, no. 2

241--256

EN

Dauricine has a variety of pharmacological properties including anti-inflammatory, anti-arrhythmic, and antihypertensive effects as well as reversing multidrug resistance (MDR) of cancer cells. While its therapeutic application is increasing, its bioavailability of different administration routes has not been studied. In the present study, we developed and validated a liquid chromatography/electrospray ionization mass spectrometry method (LC-MS/MS). Using this method, we quantified dauricine in rat plasma after administration via intravenous (i.v.) injection, per oral (p.o.), and intraperitoneal injection (i.p.). Our results indicated that this method detected plasma dauricine with a good linearity in the range of 1.95–1000.00 ng/mL (r = 0.9997). The extraction method showed an average intra- and inter-day recovery of 98.21–104.35% and 98.0–103.58%, respectively. Dauricine showed a fast absorption and widespread distribution after administration in all three tested routes. After intravenous administration (2.5, 5.0, 10.0 mg/kg), the pharmacokinetics of dauricine exhibited a first-order kinetics. In addition, dauricine showed a slow elimination with a long half-life (t1/2z) and double peaks phenomenon following p.o. and i.p. administration. Furthermore, using area under the plasma concentration-time curve (AUC), we calculated absolute bioavailability, which was over twofold higher when administered via i.p. than via p.o. administration. The newly obtained information from our study will provide important reference for dauricine dose and administration route in designing dauricine therapy for applicable diseases.

20

Research on Management Policy and National Real Estate Climate Index in China

An H., Ding Y., Gao X., Li J.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 9b

25-28

EN

Using ARIMA time series analysis method, this paper predicts NRECI from May to December 2011. Then detailed analysis is made of the NRECI trend and the major management policies introduced in corresponding periods. The results show that NRECI is closely related with management policy of real estate industry in China. The development trend of the NRECI from May to December 2011 indicates that the authorities should take moderate management measures to keep the stable trend sustained.

PL

W artykule przedstawiono metodę obliczania iprzewidywnia współczynnika NRECI (National Real Estate Climate Index). Do tego celu wykorzystano metodę analizy szeregu ARIMA.