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1

Study on optimization simulation of SCR denitration system for marine diesel engine

Du J., Li R. N., Wu X., Zhang Y.

Polish Maritime Research

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2018

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S 3

13--21

EN

With the rapid development of shipbuilding industry exhaust world is also very harmful one kind of environmental issues, and the ship marine diesel engine exhaust gas is mainly produced, so in recent years it has developed a diesel engine SCR system. SCR system can control emissions of nitrogen oxides in the exhaust of vessel, furthermore air pollution can be reduced. The main goal of article was using fluent software to correct SCR system selection and flue gas flow under different size best deflector arrangement is simulated. Next goal is further optimize the structure of the SCR system.

2

Effects of Physiological Integration and Phosphorus on Spread of Alternanthera philoxeroides from Soil to Chromium-Contaminated Aquatic Habitats

Xu L., Wu X.

Polish Journal of Ecology

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2018

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Vol. 66, nr 4

369--381

EN

Aquatic ecosystems are receivers for various pollutants, for instance, Chromium (Cr, one of the toxic heavy metals) and phosphorus (one of the biggest causes of water eutrophication). Such contaminants have brought serious impact on health and security of aquatic ecosystems. Physiological integration between the integrated ramets of clonal plants can increase their tolerance to environmental stress. It is hypothesized that physiological integration and phosphorus could facilitate the expansion of amphibious clonal plants from soil to Cr-polluted aquatic habitats. This study was conducted to primarily examine how physiological integration and phosphorus affected the effects of Cr on plant growth and population expansion. An amphibious clonal herbaceous plant Alternanthera philoxeroides was used to simulate the spread process by induced stolon connection or disconnection, Cr pollution and different levels of phosphorus in aquatic habitats. We found that Cr pollution deployed to apical ramets directly decreased the growth and photosynthetic parameters of the apical ramets that lacked connections to the basal ramets, but these effects could be mitigated by stolon connections. Cr pollution had no effects on these disconnected basal ramets, but the transmission of Cr from the apical parts via connected stolons negatively affected the growth of the basal ramets. Increasing the phosphorus not only increased the growth but also decreased the levels of Cr that accumulated in the plant tissues and the bioactivity of Cr. These results indicated that increasing the phosphorus could benefit the population expansion and establishment of A. philoxeroides through physiological integration from terrestrial to Cr-polluted aquatic habitats.

3

Magnetic seeding depression in flotation of hematite ore slimes

Yue T., Wu X.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 3

701--712

EN

Magnetic seeding depression (MSD), i.e. adding organic depressant (such as starch) and magnetic seeds and applying a low field intensity pre-magnetization for depressing target mineral in flotation, was investigated in the reverse flotation of hematite ore slimes. Flotation tests found that the iron recovery increased with the addition of magnetic seeds; the depressing ability of starch in flotation was further enhanced by the MSD. The increased adsorption density of starch on target mineral hematite and apparent size enlargement of fine minerals are two reasons for the MSD. Based on FTIR, VSM and AFM measurements it was demonstrated that the starch acted as a bridging adsorption between hematite and magnetic seeds by hydrogen bonding and chemisorption, and resultant coverage of the magnetic seeds and starch on hematite increased the magnetic susceptibility, being beneficial to the agglomeration of hematite fines by reducing the external magnetic intensity needed for agglomeration to take place. The model of the MSD was proposed.

4

Development of Female Torso Classification and Method of Patterns Shaping

Wu X., Kuzmichev V., Peng T.

Autex Research Journal

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2018

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Vol. 18, no. 4

419--428

EN

Our study presents a new pattern-making approach that is composed of three major steps: to establish the new torso classification; to improve the pattern shaping method; to solve the problem of misfit of female dresses. New additional measurements were obtained from full bust, waist and hip circumferences and divided between front and back parts separately from 3D body scanning data. By creating 8 new torso subtypes Y1, Y2, A1, A2, B1, B2, C1, and C2, which reflect the body characteristics and torso morphology through distribution of bust girth between the front and the back, we have developed the Chinese female torso classification. On the basis of the new classification and the Japanese method of pattern block drafting, we improved the method of calculation of waist darts and the shaping of two kinds of female dresses: first kind doesn’t have the horizontal waist seam (one-piece dress) and second kind has the waist horizontal seam (two-pieces dress containing from the top and the skirt). The new torso subtypes and new pattern block shaping approach are taken into attention as the body characteristics will significantly improve the quality of clothes. New method of pattern pieces shaping in according with the characteristic features of a 3D virtual avatar allows to integrate this virtual pattern-generating approach into the pattern-making systems.

5

Texture Analysis Method Based on Fractional Fourier Entropy and Fitness-scaling Adaptive Genetic Algorithm for Detecting Left-sided and Right-sided Sensorineural Hearing Loss

Wang S., Yang M., Li J., Wu X., Wang H., Liu B., Dong Z., Zhang Y.

Fundamenta Informaticae

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2017

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Vol. 151, nr 1/4

505--521

EN

To detect the sensorineural hearing loss (SNHL) from healthy people accurately, we used magnetic resonance imaging (MRI) to obtain the imaging data, and then proposed a new computer-aided diagnosis (CAD) system, on the basis of texture analysis method. In the first, we extracted 12-element feature from each brain image via fractional Fourier entropy (FRFE). Afterwards, multilayer perceptron (MLP) was employed as the classifier, which was trained by a novel fitness-scaling adaptive genetic algorithm (FSAGA). The statistical analysis over 49 subjects showed the overall accuracy of our method yielded 95.51%. Experimental results performed better than four state-of-the-art weight optimization methods, and this CAD system give significantly better performance than manual interpretation.

6

Mission reliability modeling and evaluation of multi-mission phased mission system based on extended object-oriented Petri net

Wu X., WU X.

Eksploatacja i Niezawodność

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2017

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Vol. 19, no. 2

244--253

PL

Wielozadaniowy system o misjach okresowych (ang. multi-mission phased mission system, MM PMS) jest rozszerzoną wersją systemu o misjach okresowych (ang. phased mission system, PMS). MM PMS to system, w którym zachodzi konieczność wykonania więcej niż jednego zadania w danym okresie czasu. Zadania (misje) w MM-PMS zazwyczaj charakteryzują się następującymi cechami: mają różne czasy rozpoczęcia i trwania; mają wspólne elementy, ale występujące w różnych kombinacjach; różnią się prawdopodobieństwem wystąpienia. W związku z tym, modelowanie i ocena niezawodności MM-PMS jest bardziej skomplikowana niż w przypadku PMS. W pracy przedstawiono ogólną metodologię opartą na idei rozszerzonej sieci obiektowej Petriego (EOOPN) służącą do modelowania niezawodności misji oraz oceny MM-PMS o podanych cechach. Proponowany model EOOPN dla MM-PMS obejmuje pięć modeli zależnych przedstawiających MM-PMS na różnych poziomach szczegółowości. Aby wykazać skuteczność proponowanego modelu, porównano wyniki oceny niezawodności misji dla prostego przypadku MM-PMS dokonanej metodami symulacji EOOPN z oceną przeprowadzoną metodą binarnego diagramu decyzyjnego (BDD). Wyniki pokazują, że model EOOPN można z powodzeniem stosować do obrazowania dynamiki oraz oceny niezawodności MM-PMS.

EN

Multi-mission phased mission system (MM-PMS) is an extension of phased mission system (PMS) which is required to complete more than one missions for a period of time. Missions in MM-PMS usually have following characteristics: they have different mission starting and duration times; they share common components but with different combinational requirements; they have unequal occurrence probabilities. Therefore, reliability modeling and evaluation of MM-PMS is more complicated than that of PMS. This paper presents a general methodology based on the extended object-oriented Petri net (EOOPN) for mission reliability modeling and evaluation of MM-PMS with these characteristics. The proposed EOOPN model for MM-PMS includes five sub-models depicting MM-PMS at different levels of granularity. To demonstrate the effectiveness of the proposed model, mission reliability evaluation results of a simple MM-PMS case by EOOPN simulation methods are compared with those by binary decision diagram (BDD). Results show that the EOOPN model is suitable to depict the dynamics and to evaluate the reliability of MM-PMS.

7

Distribution Characteristics of TOC, TN and TP in the Wetland Sediments of Longbao Lake in the San-Jiang Head Waters

Lu S., Si J., Qi Y., Wang Z., Wu X., Hou C.

Acta Geophysica

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2016

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Vol. 64, no. 6

2471--2486

EN

The study deals with the distribution of nutrients in wetland sediments, which provide the basis for revealing the wetland eutrophication processes and mechanisms of internal pollution sources. The total organic carbon (TOC), total nitrogen (TN), and total phosphorus (TP) contents and distribution characteristics of sediment samples were examined. The results showed that the TOC concentration ranged from 3.81 to 15.6 g/kg, the TN concentration ranged from 0.21 to 1.18 g/kg with a mean concentration of 0.66 g/kg, and the TP concentration ranged from 0.16 to 0.35 g/kg with a mean of 0.23 g/kg. Statistical analysis showed close correlations between TOC and TN (R2 = 0.96), and TN and TP (R2 = 0.97), which indicated that the TN and TP in the sediments were from similar sources. The concentrations of TOC, TN, and TP in Longbao Lake wetland sediments were too low for eutrophication to occur. Our investigation indicated that Longbao Lake undergoes natural evolution rather than anthropogenic activities.

8

Fiber-optic accelerometer based on a modal interferometer using a thin-core fiber

Wang X, Wu X, Li S, Ge Q, He T, Yu B

Optica Applicata

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2015

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Vol. 45, nr 3

317--325

EN

A compact fiber-optic accelerometer based on a modal interferometer, which is fabricated by misaligned splicing of a short section of a thin-core fiber between two sections of a standard single-mode fiber, is demonstrated experimentally. A spectrum analysis method is used to detect an acceleration signal rapidly. The experimental results show that the thin-core fiber-based fiber-optic accelerometer has a minimum detectable acceleration of 3.3×10–3g (g – gravitational acceleration), and a wide frequency response range from 10 to 1200 Hz. Moreover, the proposed accelerometer exhibits the advantages of low cost, simple structure and easy fabrication.

9

Phase, microstructure and microwave dielectric properties of A-site deficient (La, Nd) 2/3TiO3 perovskite ceramics

Saleem M., Iqbal Y., Qin S., Wu X., Zhu F.

Materials Science Poland

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2015

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Vol. 33, No. 1

126--130

EN

(La, Nd)2/3TiO3 ceramics were prepared through a conventional solid state mixed oxide route. For phase and microstructure analysis, XRD and SEM were used, respectively. Microwave dielectric properties were measured using a network analyzer. XRD patterns revealed the formation of the parent (La, Nd)2/3TiO3 phase along with (La, Nd)4Ti9O24 as a secondary phase. The microstructure consisted of rectangular and needle shaped grains, which decreased in size from 4 μ m to 2 μm with an increase in sintering temperature from 1300 °C to 1350 °C. Decrease in grain size caused an increase in density of the samples from 4.81 g/cm3 to 5.17 g/cm3. Microwave dielectric properties of the samples calcined and sintered in air atmosphere were εr = 40.35, Q × f = 3499 GHz and τ f = 0 ppm/°C, whereas for a sample calcined in nitrogen and sintered in air they were εr = 40.18, Q × f = 4077 GHz and τ f = +4.9 ppm/°C, respectively.

10

UPLC/Q-TOF-MS Analysis for Identification of Hydrophilic Phenolics and Lipophilic Diterpenoids from Radix Salviae Miltiorrhizae

Yang S. T., Wu X., Rui W., Guo J., Feng Y. F.

Acta Chromatographica

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2015

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Vol. 27, no. 4

711--728

EN

A rapid method has been used for simultaneous identification of both hydrophilic and lipophilic compounds from Radix Salviae Miltiorrhizae (RSM, the root of Salvia miltiorrhiza BGE.) by ultra-performance liquid chromatography/quadrupole time-offlight mass spectrometry (UPLC/Q-TOF-MS). A total of 58 compounds extracted by methanol were detected and tentatively identified within 20 min, including hydrophilic phenolics, lipophilic diterpenoids, a verbascose, and several organic acids. These compounds were separated on an Acquity UPLC BEH C18 column and identified based on tandem mass spectrometry (MS/MS) fragmentation patterns under the positive and negative ion modes, respectively. Among them, micranthin B and 9-oxo-10E,12Zoctadecadienoic acid were reported in RSM for the first time. Their fragmentation patterns in electrospray ionization (ESI)—MS/MS spectra were first investigated by matching their accurate molecular masses. This contribution presented one of the first reports on the analysis of hydrophilic phenolics and lipophilic diterpenoids from Radix Salviae Miltiorrhizae using UPLC/Q-TOF-MS. The results demonstrated that UPLC/Q-TOF-MS method could be applied to rapidly and expediently describe and provide comprehensive chemical information for simultaneous analysis of two different polar components in RSM.

11

Stimulate economic growth by improving transport infrastructure – a lesson from China

Wang X., Deng D., Wu X.

Transport Problems

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2014

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T. 9, z. 4

63--72

EN

This paper uses Feder model to test impacts of transport infrastructure on economic growth. With China provincial data from 1990-2010 the empirical models, including Basic model, Time-Lag model and Spatial model, demonstrate that transport infrastructure does have a positive Spillover Effect on economic growth. However, Direct Effect on economic growth is negative possibly due to Crowding-Out Effect and productivity difference between sectors. The research also proves the Spillover Effects are becoming weaker as time passed. Finally, Spatial Spillover Effect or Network Effects are confirmed.

DE

Diese Thesis benutzt Feder-Model, um die Auswirkung der Transportinfrastruktur, die auf das wirtschaftliche Wachstum zu untersuchen. Mit den Daten aus chinesischen Provinzen zwischen 1990 und 2010 durch das empirische Modell, in dem das Basic-Model, Time-Lag-Model und Spatial-Model beinhaltet, kann man dadurch demonstrieren, dass die Transportinfrastruktur eine positive Spillover-Effekt auf das wirtschaftliche Wachstum auswirkt. Direkte Effekt auf das wirtschaftliche Wachstum ist jedoch möglich negativ, durch die Crowding-Out Effekt und Unausgeglichenheit der Produktivität zwischen Sektoren. Diese Studie beweist auch, dass die Spillover-Effekte mit vergangener Zeit schwächt wird. Außerdem werden die Spatial-Spillover-Effekt oder Network-Effekt nachgewiesen.

12

Finite Element Modelling of Atomic Force Microscope Cantilever beams with Uncertainty in Material and Dimensional Parameters

Wang B., Wu X., Rusinek A., Gan T.

Engineering Transactions

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2014

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Vol. 62, iss. 4

403–-421

EN

The stiffness and the natural frequencies of a rectangular and a V-shaped micro-cantilever beams used in Atomic Force Microscope (AFM) were analysed using the Finite Element (FE) method. A determinate analysis in the material and dimensional parameters was first carried out to compare with published analytical and experimental results. Uncertainties in the beams’ parameters such as the material properties and dimensions due to the fabrication process were then modelled using a statistic FE analysis. It is found that for the rectangular micro-beam, a ±5% change in the value of the parameters could result in 3 to 8-folds (up to more than 45%) errors in the stiffness or the 1st natural frequency of the cantilever. Such big uncertainties need to be considered in the design and calibration of AFM to ensure the measurement accuracy at the micron and nano scales. In addition, a sensitivity analysis was carried out for the influence of the studied parameters. The finding provides useful guidelines on the design of micro-cantilevers used in the AFM technology.

13

EL and ITG Characterization of Large Areas Black Silicon Solar Cells VIA Screen Painting

Tang Y., Zhou C., Wang W., Zhou S., Zhao Y., Liu X., Zhao L., Li H., Chen J., Yan B., Fei J., Cao H., Wu X.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

151--154

EN

A simple process of texturing silicon (Si) surfaces using gold (Au)-catalyzed wet chemical etching was used to form black Si (BS) on a (100) p-type substrate. The surface became uniformly black after 6 min, with a resulting reflectivity of < 2% over the 400 nm to 1100 nm wavelength range. Large areas (153.18 cm 2) of black Si solar cells (BSSCs) with an n + -p-p + structure were also fabricated using conventional processes, including POCl3 diffusion, screen printing, and co-firing. The resulting cells were divided into two groups according to the emitter (46 and 37 Ω/), and their output parameters were studied. The best convention efficiency (Eff) was < 10%. The open-circuit voltage (Voc) was particularly low because of poor surface passivation, and the shunt resistance (Rsh) linearly decreased with the series resistance (Rs). Electroluminescence (EL) and infrared thermography (ITG) measurements were conducted to characterize the BSSCs. Both the emissivity and temperature were low and nonuniform. Optimizing the fabrication process by reducing the etching depth and lowering the dopant sheet resistance led to significant improvement in Voc (~48 mV) and Eff (~3.8% absolute). EL and ITG measurements indicate that Rs is another important factor that accounts for the poor properties of the BSSCs.

PL

Do wytworzenia czarnego krzemu (BS) na podłożu typu p-Si(100) zastosowano prosty sposób teksturowania powierzchni krzemowej metodą chemicznej akwaforty na mokro z zastosowaniem, jako katalizatora, nanocząstek złota (Au). Podłoże staje się jednolicie czarne po 6 min, osiągając współczynnik odbicia < 2% w zakresie długości fali od 400 nm do 1100 nm. Wykonano również dużą powierzchnię czarnych krzemowych ogniw słonecznych (BSSC), ze strukturą n + - p -n +, konwencjonalnymi metodami obejmującymi dyfuzję POC13,drukowanie maski i wyżarzanie. Otrzymane ogniwa dzielą się na dwie grupy w zależności od emitera (46 i 37Ω/): zbadano ich wyjściowe parametry. Najlepsza uzyskana wydajność wynosi < 10%. Napięcie obwodu otwartego (Voc) jest szczególnie niskie z powodu słabej pasywacji powierzchni, a rezystancja równoległa (Rsh) liniowo maleje z rezystancją szeregową (Rs). Charakterystykę BSSC określają pomiary elektroluminescencji (EL) i tomografii w podczerwieni (ITG).Zarówno emisyjność jak i temperatura są niskie i niejednorodne. Optymalizacja procesu wykonana przez zmniejszenie głębokości akwaforty i obniżenie rezystancji warstwy domieszkowania prowadzi do znaczącej poprawy Voc (ok. 48mV) i Eff (ok. 3,8%).

14

Distribution Optimization Based on Feasible Direction Metod for Horizontal Well Perforation

Wang Y., Wu X., Wang R., Wu H., Yang Z.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

239--242

EN

The horizontal wellbore pressure and reservoir heterogeneity are major factors in the horizontal well uneven inflow. Given the situation, it is to establish balanced production of horizontal wells as the objective function, and holes dense as the optimization which is a typical constrained nonlinear optimization. By feasible direction method, it is to obtain distribution optimization results, in order to control the production pressure within horizontal section and to realize uniform advancing of flow profile in the horizontal segment.

PL

W artykule przedstawiono metodę optymalizacji rozmieszczenia i gęstości odwiertów oraz zbalansowania ilości studzien poziomych, co zapobiegnie nierównomiernym rozpływom cieczy. Dodatkowo pozwoli to na kontrolę ciśnienia przy wytwarzaniu poziomych sekcji oraz jednorodne przedłużanie profilu przepływu w poziomym segmencie.

15

Numerical investigation of the inner flow in a centrifugal pump at the shut-off condition

Liu H., Wu X, Tan M.

Journal of Theoretical and Applied Mechanics

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2013

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Vol. 51 nr 3

649--660

EN

The unsteady flow fields in a centrifugal pump at the shut-off condition (SOC) are simulated by the Unsteady Reynolds Averaged Navier-Stokes (URANS) approach. To improve simulation accuracy and assign the boundary condition, special 3D models are made. Three-dimensional URANS equations are solved on high-quality unstructured grids with the shear stress transport turbulence model by using the computational fluid dynamics (CFD) code CFX-11.0. Furthermore, the numerical simulation results are validated by particle image velocimetry (PIV) measurements. The main goal of the study is, on one hand, the validation of the numerical procedure proposed, and on the other hand, the detailed analysis of the unsteady inner flow field distribution and pressure fluctuation in the centrifugal pump at SOC. In addition, the head of the pump at SOC is predicted based on CFD results. The flow analysis indicates that there exists two eddies in each impeller flow passage, and the velocity at the volute diffusion part is very low. The amplitudes of pressure fluctuation at ƒr (impeller rotation frequency) and 3ƒr dominate in the impeller, while the pressure fluctuation at ƒb (blade passing frequency) is dominant in the volute.

16

Preparation and Characterisation of PSA/CNT Composites and Fibres

Chen Z., Xin B., Wu X., Wang X., Du W.

Fibres & Textiles in Eastern Europe

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2012

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Vol. 20, no. 5 (94)

21--25

EN

In this paper, polysulfonamide/carbon nanotube (PSA/CNT) composite solutions with different CNT contents were prepared using the physical blending method. Corresponding composite fibers were extruded and fabricated through a set of wet spinning units, and composite membranes were prepared by the spin-coating method. The PSA/CNT composite fibers and membranes were characterised by means of SEM, FTIR and XRD among others. The mechanical, thermal and electrical properties were also analysed in this study. The experimental results show that CNT at low contents can be distributed homogeneously in the PSA matrix. Furthermore the molecular structure and chemical composition of PSA does not undergo an obvious change. Crystallisation in the PSA can be promoted at low CNT contents because the nano-particles can act as a nucleation agent. Moreover the electrical conductivity of PSA can be improved significantly by the blending of CNT.

PL

Przygotowano szereg zestawów polisulfonamidu i różnej ilości nanorurek węglowych. Z przygotowanego kompozytu wyprodukowano włókna i folie, które zostały scharakteryzowane przez skaningową mikroskopię elektronową, spektroskopię w podczerwieni i dyfrakcję rentgenowską. Analizowano również właściwości mechaniczne, przewodność cieplną i elektryczną otrzymanych próbek. Wyniki wskazują, że przy małym stężeniu nanorurek węglowych mogą one być rozprowadzone jednorodnie w całej matrycy; struktura molekularna i właściwości matrycy PSA nie ulegają zmianie; krystalizacja w matrycy PSA inicjowana jest przez nanorurki; przewodność elektryczna kompozytu zależy w dużym stopniu od ilości dodanych nanorurek.

17

Self-assembling micelles obtained from PLLA/PEG and PDLA/PEG block copolymers in aqueous solutions

Wu X, Li S.

Engineering of Biomaterials

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2012

|

Vol. 15, no. 113

6--8

EN

A series ofpolylactide-poly(ethylene glycol) (PLA- PEG) block copolymers were synthesized by ring-opening polymerization of L- or D-lactide in the presence of mono- or dihydroxyl PEG, using nontoxic zinc lactate as catalyst. Micelles were then prepared by direct dissolution of the obtained copolymers in aqueous medium without heating or using any organic solvents. Aqueous gel permeation chromatography and dynamic light scattering measurements were carried out to characterize the resulting micelles. Generally, mixed micelles containing both PLLA/PEG and PDLA/PEG copolymers appear lager and more compact compared to single ones. However, the size of mixed micelles is smaller than that of single ones which exhibit an anisotropic structure since stereocomplexation disfavors the formation of anisotropic micelles. The copolymer parameters such as structures, molar mass and PEG fraction strongly influence the formation of anisotropic micelles, and thus lead to various micellar sizes.

18

Model badania potwierdzającego niezawodność dla dwumianowych systemów o rosnącej niezawodności

Wu X., Liu Q.

Eksploatacja i Niezawodność

|

2010

|

nr 2

55-58

PL

Wiele złożonych systemów inżynieryjnych przechodzi proces wzrostu niezawodności w kolejnych etapach badań. Większość istniejących modeli badań potwierdzających niezawodność nie uwzględnia jednak wzrostu niezawodności. W niniejszym artykule przedstawiono model badania niezawodności dla systemów dwumianowych o 2 etapach testowych, który bierze pod uwagę możliwy wzrost niezawodności. Określono wskaźniki prawdopodobieństwa dla różnych możliwych sytuacji oraz wyprowadzono statystyczne reguły decyzyjne. Podany przykład ilustruje względnie niższe ryzyko decyzyjne proponowanego modelu w stosunku do tego, jakie niosą klasyczne modele badań.

EN

Many complex engineering systems experience reliability growth in successive test stages. In most existing reliability demonstration test models, reliability growth is not incorporated. In this paper, for binomial systems with 2 test stages, a reliability demonstration test model is presented that takes possible reliability growth into consideration. Likelihood ratios are defi ned for various possible situations, and statistical decision rules are derived. With a given example, the relative lower decision risk of the proposed model is illustrated by comparison with that of classical demonstration test models.

19

Phylogenetic diversity of bacteria and Archaea associated with the marine sponge Pachychalina sp.

Cheng N., Fang Z., Huang H., Fang Z., Wu X., Bao S.

Polish Journal of Ecology

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2008

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Vol. 56, nr 3

505-510

EN

Molecular techniques were employed to document the microbial diversity associated with the marine sponge Pachychalina sp. from South China Sea in March 2003. Using the total microbial DNA as template, bacterial and archaeal 16S rDNAs were amplified by PCR with universal primers. Amplified products were cloned, sequenced and secondarily amplified by PCR. Then the secondarily amplified products were purified to be further characterized by amplified rDNA restriction analysis (ARDRA). According to the enzyme restriction mapping, the apparent difference among them were disclosed. 22 bacterial cloned partial sequences were acquired and most of them were related to proteobacterium. Also, 7 archaeal cloned partial sequences were acquired and a phylogenetic tree was built up.Result shows the prolific bacterial and archaeal diversity of marine sponge Pachychalina sp.

20

Privacy Preserving Database Generation for Database Application Testing

Wu X., Wang Y., Guo S., Zheng Y.

Fundamenta Informaticae

|

2007

|

Vol. 78, nr 4

595-612

EN

Testing of database applications is of great importance. Although various studies have been conducted to investigate testing techniques for database design, relatively few efforts have been made to explicitly address the testing of database applications which requires a large amount of representative data available. As testing over live production databases is often infeasible in many situations due to the high risks of disclosure of confidential information or incorrect updating of real data, in this paper we investigate the problem of generating synthetic databases based on a-priori knowledge about production databases. Our approach is to fit the general location model using various characteristics (e.g., constraints, statistics, rules) extracted from a production database and then generate synthetic data using model learned. The generated data is valid and similar to real data in terms of statistical distribution, hence it can be used for functional and performance testing. As characteristics extracted may contain information which may be used by attackers to derive some confidential information about individuals, we present our disclosure analysis method which applies cell suppression technique for identity disclosure and perturbation for value disclosure analysis.