Wyniki wyszukiwania - BazTech

1

Technical application of petroleum logging instruments in marine logging

Gu G., Zhao P., Wang L., Guo H.

Polish Maritime Research

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2018

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S 3

22--28

EN

To solve the problem of offshore oilfield development, based on the newly introduced pulsed neutron oxygen activation logging instrument, the application research of test design and interpretation method was carried out and applied to actual production. The structure, technical indicators and logging principles of pulsed neutron oxygen activation logging tools were introduced. The test design under different well conditions was studied, including general positive and negative injection, oil sleeve injection, single oil pipe configuration and multitubing configuration. A large amount of field test data was collected and analysed technically. A set of effective interpretation models was proposed. The corresponding interpretation software was developed. A set of test design methods and operating specifications for different well conditions were developed. Based on the conventional interpretation method, the peak selection, the double-tuber peak identification and the carbon dioxide flooding interpretation method were added. The results show that the test design and interpretation methods were applied well through a large number of field tests and production applications. Therefore, pulsed neutron oxygen activated injection profile logging technology is successfully applied in offshore oil fields.

2

Heat transfer enhancement of graphite–modified concrete energy piles

Guo H., Qiao L., Xiao Y., Ren X.

Journal of Power Technologies

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2018

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Vol. 98, nr 4

345--351

EN

Designed for utilizing the ground-source systems for heating and cooling, the use of energy piles in commercial and residential buildings has increased exponentially especially in Europe. The heat transfer efficiency of energy piles may directly influence the energy-saving effect on buildings. Apart from the optimization of pipe laying, many other factors can also influence the heat transfer efficiency of energy piles. In this study, a new method that can increase the heat transfer efficiency of energy piles was proposed to explore the influences of adding graphite powder with high thermal conductivity to pile concrete on the heat transfer efficiency of energy piles. The thermal resistance models of energy piles in three different pipe-burying modes were constructed by combining the 2D plane method and the heat transfer mechanism of energy piles. The internal heat transfer characteristics of energy piles at different temperatures, graphite contents, and pipe-burying modes were discussed by combining the indoor thermal conductivity test of graphite-modified concrete. The external heat transfer characteristics of graphite-modified concrete energy piles were analyzed through numerical simulation analysis. Results demonstrate that the increase in graphite contents is beneficial to heat transfer in energy piles. In particular, thermal conductivity significantly increases when the graphite content exceeds 5%. The high temperature in the pipe is also conducive to the thermal conductivity of the energy pile. The thermal conductivity of the concrete samples with 8% graphite content in an environment at 40°C is 1.35 times that at 20°C. The heat transfer efficiency of the spiral coil-type energy pile is higher than those of single-U and double-U tube energy piles. The proposed method provides a certain reference for improving the heat transfer efficiency of energy piles and constructing the internal and external heat transfer models in energy piles.

3

Assessment of usefulness of the mems-based integrated navigation unit in car navigation

Uradziński M., Rapiński J., Tomaszewski D., Śmieja M., Guo H., Yu S., Jian X.

Technical Sciences / University of Warmia and Mazury in Olsztyn

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2017

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nr 20(4)

321--331

EN

Due to the development of MEMS, there is an opportunity to build a low-cost integrated navigation systems, operating independently of horizon visibility. This paper presents the proposal of an integrated GPS/IMU platform using MEMS technology. In order to verify the performance of a system built at the University of Warmia and Mazury, an experiment was conducted. In this experiment a precise Javad GNSS receiver, commercial grade GPS/IMU XW – ADU5660 and own-built system were used. The experiment was conducted to compare the results obtained from self built device with the working military integrated navigation unit. During the study all three devices were mounted inside moving vehicle. The car drove route inside the Kortowo campus, during which, all equipment performed measurements. Then, the results from both integrated systems were compared with RTK (Real Time Kinematic) results from Javad receiver. Experiments prove that the performance of own device is comparable to the commercial device.

4

Measurement-based harmonic current modeling of mobile storage for power quality study in the distribution system

Wenge C., Guo H., Roehrig C.

Archives of Electrical Engineering

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2017

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Vol. 66, nr 4

801--814

EN

Electric vehicles (EVs) can be utilized as mobile storages in a power system. The use of battery chargers can cause current harmonics in the supplied AC system. In order to analyze the impact of different EVs with regardto their number and their emission of current harmonics, a generic harmonic current model of EV types was built and implemented in the power system simulation tool PSS®NETOMAC. Based on the measurement data for different types of EVs three standardized harmonic EV models were developed and parametrized. Further, the identified harmonic models are used by the computation of load flow in a modeled, German power distribution system. As a benchmark, a case scenario was studied regarding a high market penetration of EVs in the year 2030 for Germany. The impact of the EV charging on the power distribution system was analyzed and evaluated with valid power quality standards.

5

Allometric Partitioning Theory Versus Optimal Partitioning Theory : The Adjustment of Biomass Allocation and Internal C-N Balance to Shading and Nitrogen Addition in Fritillaria unibracteata (Liliaceae)

Guo H., Xu B., Wu Y., Shi F., Wu C., Wu N.

Polish Journal of Ecology

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2016

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Vol. 64, nr 2

189--199

EN

Fritillaria unibracteata is a classic perennial alpine herb. In this study, we examined it's responses to shading (SH) and nitrogen addition (NA), as well as its correlation with internal C-N balance to detect how it adjusted to the changes of habitat conditions. Randomized block experiment was carried out in the field in Chuanbeimu Research Station in Songpan County, Sichuan Province, China (32°09′54″N, 103°38′36″E, altitude 3300 m a.s.l.). Two growing seasons after NA and SH, Fritillaria unibracteata's total plant biomass decreased significantly, with the proportion of biomass allocated to aboveground significantly increased. In addition, in this study, under both SH and NA treatments, Fritillaria unibracteata increased its biomass allocation to above-ground, which consisted with optimal partitioning theory. Moreover, Fritillaria unibracteata's biomass allocation was significantly correlated with its internal C-N status, regardless of nitrogen and light condition. We conclude that Fritillaria unibracteata optimizes its biomass allocation between root and shoot by adjusting its internal C-N balance, which would not be changed by the specialized resource storage organ-bulb.

6

A novel approach to photonic generation of periodic triangular radio frequency waveforms

Xiang P., Guo H., Chen D., Zhu H., Wu C.

Optica Applicata

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2015

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Vol. 45, nr 3

381--391

EN

A novel approach to photonic generation of triangular radio frequency waveforms with a tunable repetition rate is proposed and analyzed. In the proposed system, a continuous-wave light is modulated by a reference microwave signal through a polarization modulator, and then its output optical sidebands are manipulated by a microwave photonic filter with a negative tap. By properly adjusting the system parameters, full-duty-cycle triangular radio frequency waveforms can be generated after optical-to-electrical conversion, and its repetition rate (frequency) can be tuned in a wide range. A model describing the proposed system is derived, which is verified via computer simulations.

7

Indoor positioning based on foot-mounted IMU

Guo H., Uradziński M., Yin H., Yu M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2015

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Vol. 63, nr 3

629--634

EN

The paper presents the results of the project which examines the level of accuracy that can be achieved in precision indoor positioning by using a pedestrian dead reckoning (PDR) method. This project is focused on estimating the position using step detection technique based on foot-mounted IMU. The approach is sensor-fusion by using accelerometers, gyroscopes and magnetometers after initial alignment is completed. By estimating and compensating the drift errors in each step, the proposed method can reduce errors during the footsteps. There is an advantage of the step detection combined with ZUPT and ZARU for calculating the actual position, distance travelled and estimating the IMU sensors’ inherent accumulated error by EKF. Based on the above discussion, all algorithms are derived in detail in the paper. Several tests with an Xsens IMU device have been performed in order to evaluate the performance of the proposed method. The final results show that the dead reckoning positioning average position error did not exceed 0.88 m (0.2% to 1.73% of the total traveled distance – normally ranges from 0.3% to 10%), what is very promising for future handheld indoor navigation systems that can be used in large office buildings, malls, museums, hospitals, etc.

8

Usefulness of nonlinear interpolation and particle filter in Zigbee indoor positioning

Zhang X., Guo H., Wu H., Uradziński M.

Geodesy and Cartography

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2014

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Vol. 63, no. 2

219--233

EN

The key to fingerprint positioning algorithm is establishing effective fingerprint information database based on different reference nodes of received signal strength indicator (RSSI). Traditional method is to set the location area calibration multiple information sampling points, and collection of a large number sample data what is very time consuming. With Zigbee sensor networks as platform, considering the influence of positioning signal interference, we proposed an improved algorithm of getting virtual database based on polynomial interpolation, while the pre-estimated result was disposed by particle filter. Experimental result shows that this method can generate a quick, simple fine-grained localization information database, and improve the positioning accuracy at the same time.

PL

Kluczem do algorytmu pozycjonowania wykorzystującego metodę fingerprinting jest ustanowienie skutecznej bazy danych na podstawie informacji z radiowych nadajników referencyjnych przy wykorzystaniu wskaźnika mocy odbieranego sygnału (RSSI). Tradycyjna metoda oparta jest na przeprowadzeniu kalibracji obszaru lokalizacji na podstawie wielu punktów pomiarowych i otrzymaniu dużej liczby próbek, co jest bardzo czasochłonne.

9

Application the optimization models to analysis of the industrial pollutant emission in China

Zhang Z., Liu G.-D., Guo H., Liu L., Deng S.-H.

Environment Protection Engineering

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2013

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Vol. 39, nr 1

87--99

EN

An industrial planning is made based on the optimization model. Factor analysis was used to reject relativity among the environmental indicators. Then, thirty nine industries were clustered into four clusters. Lastly, optimization model was used to plan the industrial structure. Adjusting the industrial structure, it is difficult to reduce vast SO2, smoke, and dust with total industrial output value growth; the air pollutant emission only can be decreased by 10%. The parameters of smoke emission are limited constrains for the optimization. The reasonable and feasible way to solve the problem is to introduce the lower smoke emission technique of the cluster 2 and 4 industries.

10

Modelling for sound annoyance evaluation of vehicle noise based on neural network

Wang Y., Shen G., Guo H.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 7b

303--306

EN

Based on the neural network (NN) technique, a new sound quality evaluation (SQE) model for synthetical annoyance of vehicle noises is proposed in this paper. Based on the measured noise signals of a sample vehicle, the psychoacoustical models for loudness, sharpness and roughness are investigated. Annoyance values of the measured vehicle noises are estimated by a jury test following an anchor-scaled scoring method. A NN-based model for annoyance evaluation of vehicle noise, so-called VNA-NNM, is carried out. Finally, the VNA-NNM model is verified by the leave-one-out algorithm. The results suggest that the VNA-NNM model is accurate and effective for estimating sound quality of vehicle interior noises, which is instructive and useful for vehicle acoustical designs.

PL

Zaproponowano model oceny jakości dźwięku i rozdrażnienia dźwiękiem szumu samochodowego. Model bazuje na sieciach neuronowych i wykorzystuje zmierzony sygnał szumu samochodowego oraz model psychoakustyczny.

11

A Novel Single-Phase Transformerless Inverter for Grid-Connected Photovoltaic Systems

San G., Qi H., Guo H.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 12a

251-254

EN

Eliminating the leakage current is one of the most important issues for transformerless inverters in grid-connected photovoltaic system applications, where the technical challenge is how to keep the system common-mode voltage constant to reduce the leakage current. A novel singlephase three-level topology for transformerless photovoltaic systems is presented in this paper. Compared with the conventional H-bridge topology, it only needs two additional asymmetrically distributed switches, and the system common-mode voltage can be kept constant with a simple modulation scheme. Test results verify the theoretical analysis and the feasibility of the proposed topology.

PL

W artykule przedstawiono nową trójpoziomową topologię jednofazowego przekształtnika w beztransformatorowym układzie pracującym z panelami fotowoltaicznymi. System pozwala na utrzymanie stałego napięcia common-mode, poprzez wykorzystanie dodatkowych łączników oraz prostego algorytmu modulacji.

12

Conditions for tighter focusing and higher focal depth of radially polarized vector beam

Gao X, Wang Q, Yun M, Yu J, Guo H, Zhuang S

Optica Applicata

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2012

|

Vol. 42, nr 1

85--101

EN

The radially polarized vector beam has attracted much attention recently and was also used to obtain a smaller focal spot. In this paper, highly focusing properties of radially polarized vector beam are investigated by comparing them with those of linearly polarized beam. A condition was found for tighter focusing of radially polarized vector beam. The focal spot of radially polarized vector beam is not always smaller than that of linearly polarized beam. Even if only a longitudinal field component is considered, in fact, the condition for tighter focusing of radially polarized vector beam is very complicated. Therefore, more attention should be paid to the smaller focal spot generation by means of radially polarized vector beam in practical use. In addition, the focal depth of radially polarized beam decreases on increasing numerical aperture under condition of small radius ratio, and increases on increasing radius ratio. The focal depth difference between these two kinds of beams shrinks upon increasing radius ratio and numerical aperture.

13

Niezawodność i bezpieczeństwo dostaw energii z morskich systemów energetycznych

Heyde C. O., Krebs R., Komarnicki P., Guo H., Rudion K.

Elektroenergetyka : współczesność i rozwój

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2012

|

Nr 1-2(11-12)

38--48

PL

Morskie systemy energetyczne, które pozwolą zapewnić wysoką jakość zasilania, będą oparte głównie na wysokonapięciowych i stałoprądowych sieciach przesyłowych HVDC. Nadal brakuje praktycznego doświadczenia do optymalnej pracy i regulacji tych złożonych systemów i ich wpływu na zarządzanie równolegle połączonych sieci AC. Nowe koncepty muszą być opracowywane i testowane, zarówno w zakresie technologii (urządzenia pomiarowe i sterowania), jak i aplikacji (symulacyjne i wizualizacyjne). Zadaniem projektu "Sea Power Grid-Secure", finansowanego prze niemieckie ministerstwo ochrony środowiska, jest badanie niezawodności takich systemów, ich sposobów regulacji, obserwowalności, a także zabezpieczenia. Autorzy – oprócz opisu projektu – zawarli w tekście interesujące podsumowanie jego pierwszych wyników.

EN

Wind farms in the North Sea are expected to play a key role in supplying electricity to Europe in the nearest future. Therefore the issue of reliability and control of Offshore Wind Power Systems is of primary importance for the Interconnected Network of ENTSO-E in Europe and its operational safety. All the EU states need a high-quality electricity supply to meet the demands of large industrial customers. The Offshore Wind Power Systems, which will ensure high-quality supply, are designed to be based on the HVDC technology. However, we are still lacking experience to ensure optimal operation and control these complex systems and their impact on the management of interconnected AC grids. Therefore new ideas and concepts have to be developed and tested in the area of technology (measuring and control systems) and application (simulation and visualization). One of them is the project called "Sea Power Grid-Secure", financed by the German Ministry of Environment Protection, aimed to test the reliability, control, observability and security of such systems. The paper provides a description of the project and summary of its initial results.

14

High focusing of radially polarized Bessel-modulated Gaussian beam

Gao X., Gao M., Hu S., Guo H., Wang J., Zhuang S.

Optica Applicata

|

2010

|

Vol. 40, nr 4

965--974

EN

The focusing properties of radially polarized Bessel-modulated Gaussian (QBG) beam are theoretically investigated in detail by vector diffraction theory. The QBG beam contains an optical vortex. Calculation results show that the intensity distribution in focal region of radially polarized QBG beam can be altered considerably by changing beam parameter and the topological charge of the optical vortex. Beam parameter can induce remarkable focus evolution in axial direction. While topological charge adjusts intensity distribution more significantly in transverse direction, for instance, one focal spot changes into one ring pattern. And some novel focal patterns may occur, including two-peak focus, one ring focus, two-ring focus, three-ring focus, and even dark hollow focus, which is very important in optical tweezers technique.

15

Recruitment pattern of tree populations along an altitudinal gradient : Larix chinensis Beissn in Qinling Mountains (China)

Duan R., Wang X., Tu Y., Huang M., Wang C., Zhu Z., Guo H.

Polish Journal of Ecology

|

2009

|

Vol. 57, nr 3

451-459

EN

Larix chinensis Beissn is an endangered plant found only in the Qinling Mountains, Shaanxi, northwestern China. It is densely distributed in the alpine and subalpine belt on their highest peak Taibai Mountain. Age structure studies along a montane altitudinal gradient would be helpful in understanding the limiting factors on the regeneration of natural forests. The forest was divided into three transects, i.e., lower limit (2900-3000 m), mid-altitude (3100-3200 m) and upper limit (3300-3400 m). The age structures differed across altitude classes. The age structure in the low altitude transect was closed to bell-shaped and characterized by the dominance of adult trees. A reverse-J shape age structure was found in the mid-altitude transect. Multi-modal age distribution was found in the high altitude transect, and was caused by lack of young seedlings and saplings. This suggests that different limiting factors play important roles in shaping the age structure and forest regeneration at different altitudes. In the low altitude, light availability was probably the most important limiting factor. In the mid-altitudinal transect, density dependent intraspecific competition between trees likely controlled regeneration of L. chinensis. We suggest that limiting climatic factors, e.g. temperature, play an important role in determining the age structure of L. chinensis populations in highaltitude areas.

16

Learning from Skewed Class Multi-relational Databases

Guo H., Viktor H.L.

Fundamenta Informaticae

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2008

|

Vol. 89, nr 1

69-94

EN

Relational databases, with vast amounts of data–from financial transactions, marketing surveys, medical records, to health informatics observations– and complex schemas, are ubiquitous in our society. Multirelational classification algorithms have been proposed to learn from such relational repositories, where multiple interconnected tables (relations) are involved. These methods search for relevant features both from a target relation (in which each tuple is associated with a class label) and relations related to the target, in order to better classify target relation tuples. However, in many practical database applications, such as credit card fraud detection and disease diagnosis, the target tuples are highly imbalanced. That is, the number of examples of one class (majority class) in the target relation is much higher than the others (minority classes). Many existing methods thus tend to produce poor predictive performance over the underrepresented class in the data. This paper presents a strategy to deal with such imbalanced multirelational data. The method learns from multiple views (feature sets) of relational data in order to construct view learners with different awareness of the imbalanced problem. These different observations possessed by multiple view learners are then combined, in order to yield a model which has better knowledge on both the majority and minority classes in a relational database. Experiments performed on six benchmarking data sets show that the proposed method achieves promising results when compared with other popular relational data mining algorithms, in terms of the ROC curve and AUC value obtained. In particular, an important result indicates that the method is superior when the class imbalanced is very high.

17

Iron oxide(III) nanoparticles fabricated by electron beam irradiation method

Zhao B., Wang Y., Guo H., Wang J., He Y., Jiao Z., Wu M.

Materials Science Poland

|

2007

|

Vol. 25, No. 4

1143--1148

EN

Iron oxide(III) nanoparticles were fabricated by the electron beam irradiation method. The structure and morphology of the iron oxide nanoparticles were analyzed by XRD, TEM, AFM and FTIR. Phase transformation temperatures were determined by DSC-TGA. Results showed that the phase transition point and melting point decreased greatly. The size effects were discussed to explain the reason.

18

A new approach for simultaneous shape and topology optimization based on dynamic implicit surface function

Guo H., Zhao K., Wang M. Y.

Control and Cybernetics

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2005

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Vol. 34, no 1

255-282

EN

In the present paper, a new approach for structural topology optimization based on dynamic implicit surface function (DISF) is proposed. DISF is used to describe the shape/topology of a structure, which is approximated in terms of the nodal values. Then, a relationship is established between the element stiffness and the values of the implicit surface function on its four nodes. In this way and with some non-local treatments of the design sensitivities, not only the shape derivative but also the topological derivative of the optimal design can be incorporated in the numerical algorithm in a unified way. Numerical experiments demonstrate that by employing this approach, the computational efforts associated with DISF (and level set) based algorithms can be diminished. Clear optimal topologies and smooth structural boundaries free from any sign of numerical instability can be obtained simultaneously and efficiently.