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1

Starzeniowe badanie siły przyczepności pomiędzy miękkimi kauczukami silikonowymi a poli(metakrylanem metylu)

Fubao Z., Li D., Lianshui S., Yongfa Z., Hongshui Z.

Przemysł Chemiczny

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2018

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T. 97, nr 12

2110--2114

PL

Badano zmiany siły przyczepności w temperaturze pokojowej pomiędzy miękkim kauczukiem silikonowym a poli(metakrylanu metylu) (PMMA). Laminowane próbki wykonano z handlowych elastomerów silikonowych Ufi Gel P (UGP) i Silageum-Comfort (SLC), podzielono na grupy odpowiednio A1–A4 i B1–B4 i poddano starzeniu w sztucznej ślinie przez 1–360 dni. Siłę przyczepności tych próbek wyznaczono, wykorzystując uniwersalne urządzenie do testowania materiałów w sposób niszczący. Styk przyczepny obserwowano za pomocą skaningowego mikroskopu elektronowego. Badanie nie wykazało statystycznej różnicy w sile przyczepności w obrębie grup A i B (P > 0,05). Stwierdzono jednak statystyczne różnice w sile przyczepności pomiędzy grupami A i B (P < 0,05). Destrukcja polegała głównie na defekcie mieszania lub defekcie przyczepności. Styki przyczepne w próbkach wszystkich grup były jednorodne, lecz w grupie A sporadycznie obserwowano pęcherzyki. Po starzeniu w temperaturze pokojowej nie stwierdzono istotnych zmian w sile przyczepności UGP i SLC do PMMA. Siła ta osiągnęła wartość wymaganą do zastosowania klinicznego (0,44 MPa). Siła przyczepności UGP i PMMA była większa niż w przypadku SLC i PMMA.

EN

Forty-eight laminated specimens were made of 2 com. dental soft Si elastomers and in situ produced poly(Me methacrylate), aged at room temp. in artificial saliva for 1–360 days and studied for bonding strength in a destructive way by using a universal testing machine. The specimens were randomly divided into 8 groups differing in the soft lining materials and aging time. The adhesive interface was obsd. by scanning electron microscopy. The bonding strength depended only on the Si elastomer type. There was no statistical difference in bonding strength when the same Si elastomer was used. The bonding strength was higher than the required for clinical use (0.44 MPa).

2

Scatter-Hoarding the Seeds of Sympatric Forest Trees by Apodemus peninsulae in a Temperate Forest in Northeast China

Li D., Jin Z., Yang C., Yang C., Zhang M.

Polish Journal of Ecology

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2018

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Vol. 66, nr 4

382--394

EN

As the main predator and disperser of seeds, rodents play an important role in the process of vegetation regeneration by adopting different foraging and hoarding strategies in forest ecosystems. Infrared automated detection cameras and seed-tagging methods were used to understand the effects of rodents on seeds in natural environments. We chose the dominant species Apodemus peninsulae (Korean field mouse) as the focus of this study, and seeds of the three species Pinus koraiensis, Corylus mandshurica and Quercus mongolica were released and tracked in a temperate forest in northeast China. The results showed that approximately 80% of the seeds were manipulated by A. peninsulae, 15.1% of the seeds were used as food, 20.4% of the seeds were handled after feeding, 41.3% of the seeds were handled during storage, and 23.3% of the seeds remained intact. In addition, A. peninsulae preferred Q. mongolica (85.3%) and P. koraiensis (85.6%) over C. mandshurica (59.2%). The rodents frequently hoarded seeds from every species in many small, close-range, widely dispersed, single scatter-hoarded caches around the seed station. Most caches were dispersed approximately 2-4 m from the seed station. The results indicated that A. peninsulae adopted significant discriminatory processing strategies for predation, consumption, dispersal and hoarding of the different seeds of sympatric species. Seed size, proportion of kernel mass, nutrient content, and hull thickness characteristics affected the scatter-hoarding decision processes.

3

Evaluation of genetic diversity and population structure of five yellow catfish Pelteobagrus fulvidraco populations by microsatellite markers

Zhong L., Wang M., Pan J., Li D., Tang S., Bian W., Chen X.

Oceanological and Hydrobiological Studies

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2018

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Vol. 47, No. 2

99--106

EN

Yellow catfish, Pelteobagrus fulvidraco, is an important commercial freshwater species in China. Knowledge about the genetic diversity of the yellow catfish is important to support the management and conservation programs, which would subsequently support the sustainable production of this species. To investigate the genetic diversity and the structure of yellow catfish in the middle and lower reaches of the Yangtze River, 125 individuals from five lakes were genotyped using 13 microsatellite markers. Moderate genetic diversity was determined in all populations, with the observed heterozygosity (HO) ranging from 0.42 to 0.49 and the expected heterozygosity (HE) ranging from 0.51 to 0.61. Low to moderate genetic differentiation among the populations was revealed from pairwise FST values (p < 0.05), as well as from analysis of molecular variance (AMOVA). The UPGMA dendrogram and Bayesian clustering analysis indicated a correlation between genetic differences and geographic distance – four populations from the lower reaches clustered together, whereas the Poyang Lake (PY) population formed a separate cluster. The present study would be helpful in the wild stock management and artificial propagation programs for yellow catfish in the middle and lower reaches of the Yangtze River.

4

An ant-based filtering random-finite-set approach to simultaneous localization and mapping

Li D., Zhu J., Xu B., Lu M., Li M.

International Journal of Applied Mathematics and Computer Science

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2018

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Vol. 28, no. 3

505--519

EN

Inspired by ant foraging, as well as modeling of the feature map and measurements as random finite sets, a novel formulation in an ant colony framework is proposed to jointly estimate the map and the vehicle trajectory so as to solve a feature-based simultaneous localization and mapping (SLAM) problem. This so-called ant-PHD-SLAM algorithm allows decomposing the recursion for the joint map-trajectory posterior density into a jointly propagated posterior density of the vehicle trajectory and the posterior density of the feature map conditioned on the vehicle trajectory. More specifically, an ant-PHD filter is proposed to jointly estimate the number of map features and their locations, namely, using the powerful search ability and collective cooperation of ants to complete the PHD-SLAM filter time prediction and data update process. Meanwhile, a novel fast moving ant estimator (F-MAE) is utilized to estimate the maneuvering vehicle trajectory. Evaluation and comparison using several numerical examples show a performance improvement over recently reported approaches. Moreover, the experimental results based on the robot operation system (ROS) platform validate the consistency with the results obtained from numerical simulations.

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

Recovery of Iron from Copper Slag by Carbothermic Reduction and Magnetic Separation in the Presence of CaO

Chun T., Mu G., Di Z., Long H., Ning C., Li D.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 1

299--305

EN

The carbothermic reduction of copper slag at the different binary basicity (CaO/SiO2 ) was carried out for recovering iron by wet magnetic separation. Calcium carbonate is found to be capable of improving the iron recovery, as well as increasing the particle size of metallic iron significantly. Experimental evidence showed that CaO reacted with SiO2 to form calcium silicate and FeO was liberated from the 2FeO.SiO2 , decreased the content of Fe in the slags, which improved the iron recovery during the magnetic separation. The final product, assaying 90.23%Fetotal (representing a metallization degree of 93.94%) and 0.58% Cu at the iron recovery of 85.70% was achieved at the basicity of 0.60, which can be briquetted as a burden material for weathering resistant steel making by electric arc furnace to replace part of scrap.

7

Modeling and analysis of coupled flexural-torsional spinning beams with unsymmetrical cross sections

Wang J., Li D., Jiang J.

Journal of Theoretical and Applied Mechanics

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2017

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Vol. 55 nr 1

213--226

EN

The structural modeling and dynamic properties of a spinning beam with an unsymmetrical cross section are studied. Due to the eccentricity and spinning, transverse deflections along the two principal directions and the torsional motion about the longitudinal axis are coupled. The structural model of the beam is established based on the Hamilton principle and by incorporating the torsional inertia. Moreover, because of its significant influence on characteristics for the non-circular cross-sectional beam, the warping effect is considered in the formulation. The proposed model is effectively validated in two cases: the spinning beam with a symmetric cross section and the cantilevered beam with an unsymmetrical cross section. Then the effects of the spinning speed on natural frequencies and mode shapes are investigated. Numerical results reveal that the critical speed is altered with respect to noncoincidence of the centroid and the shear center. For the beams with strong warping rigidities, the warping effect cannot be neglected due to significant influence on natural frequencies.

8

Looped-chain-based active current sharing strategy in DC microgrids

Li D., Liu Y., Gu Y., Qi H.

Archives of Electrical Engineering

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2017

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Vol. 66, nr 3

559--569

EN

The integration of renewable energy sources in modern electric grids have drawn increasing attention nowadays. In order to effectively manage large-scale renewable energy sources and achieve flexible and efficient operation, the concept of microgrids have been proposed. Considering the nature of DC outputs in many distributed energy resources (DERs), DC microgrids have been extensively studied in the past years. Among the operational issues in DC microgrids, current sharing issues have become an important topic since it is highly relevant to the operation of DC microgrids. By adopting a proper design of current sharing strategy in DC microgrids, the current rating violations in each interface converter can be successfully avoided. In this paper, a looped-chainbased active current sharing strategy is proposed to realize high accuracy current sharing in DC microgrids. In particular, the output current is shared between the neighboring interface converters. Hence, following a clockwise or counter-clockwise order, a loopedchain- based control diagram can be established to share the reference value of the output current. A final status in the whole DC microgrid is that the output current of every interface converter is equalized. Hence, the desired current sharing objective can be satisfied. A MATLAB simulation model is established to verify the proposed loopedchain- based active current sharing strategy in DC microgrids.

9

Dynamic response of a base-isolated concrete rectangular liquid-storage structure under large amplitude sloshing

Cheng X., Li D., Li P., Zhang X., Li G.

Archives of Civil Engineering

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2017

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Vol. 63, nr 1

33--45

EN

Considering concrete nonlinearity, the wave height limit between small and large amplitude sloshing is defined based on the Bernoulli equation. Based on Navier-Stokes equations, the mathematical model of large amplitude sloshing is established for a Concrete Rectangle Liquid-Storage Structure (CRLSS). The results show that the seismic response of a CRLSS increases with the increase of seismic intensity. Under different seismic fortification intensities, the change in trend of wave height, wallboard displacement, and stress are the same, but the amplitudes are not. The areas of stress concentration appear mainly at the connections between the wallboards, and the connections between the wallboard and the bottom.

PL

Gdy amplituda chlupotania cieczy jest zbliżona do częstotliwości drgań struktury magazynowania substancji ciekłych (CRLSS), wówczas osiągamy rezonans i możemy zaobserwować silne zjawisko nieliniowe. Szkoda jest znacznie większa niż chlupotanie o małej amplitudzie. Obecnie brak jest odpowiedniego raportu na temat badań dynamicznej odpowiedzi struktury magazynowania substancji ciekłych z wykorzystaniem betonu izolacyjnego (CRLSS) z chlupotaniem o dużej amplitudzie, a wpływ materiałów betonowych nie jest brany pod uwagę. W związku z tym, w niniejszej pracy, w oparciu o równanie Bernoulliego, otrzymano ograniczone wysokości fali o dużej amplitudzie chlupotania oraz małej amplitudzie chlupotania. Na podstawie równań Naviera-Stokesa ustanowiono matematyczny model chlupotania o dużej amplitudzie i zbadano odpowiedź sejsmiczną CRLSS podczas chlupotania o dużej amplitudzie. Rozważając równanie Bernoulliego i zadowalający stan, chlupotanie substancji ciekłej jest liniowe, a nieliniowy kwadratowy człon jest lekceważony. W stałym i płynnym interfejsie, struktura magazynowania substancji ciekłych spełnia warunki ciągłości przemieszczania i równowagi siły oddziaływań. Właściwość mechaniczna gumowego zabezpieczenia izolacyjnego została opisana w oparciu o konstytutywną relacje modelu Mooney-Rivlin.

10

Dynamic response of rectangular prestressed membrane subjected to uniform impact load

Li D., Zheng Z. L., Liu C. Y., Zhang G. X., Lian Y. S., Tian Y., Xiao Y., Xie X. M.

Archives of Civil and Mechanical Engineering

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2017

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Vol. 17, no. 3

586--598

EN

This paper investigated the dynamic response of rectangular prestressed membrane subjected to uniform impact load theoretically and experimentally. The dynamic response proceeds in two stages, namely, forced vibration and free vibration. Firstly, the maximal displacement for forced vibration is obtained by means of the principle of minimum potential energy based on the theoretical model proposed. Then, equations of motion for the transverse free vibration are derived based on thin-plate theory, and simplified by using Galerkin method. Consequently, the analytic solutions of dynamic parameters, such as frequency, displacement, amplitude, velocity, and acceleration, for free vibration are obtained by means of the multiple-scale perturbation method. In order to identify the reliability of theoretical model, the corresponding experimental study is carried out based on the developed experimental system. Furthermore, the effects of pretension force and load on the dynamic response of membrane are discussed, respectively. The present work provides a theoretical model to calculate the dynamic response of prestressed membrane subjected to uniform impact load, and a set of experimental system to study this problem.

11

SFRs-based numerical simulation for the reliability of highly-coupled DFTS

Ge D., Li D., Lin M., Yang Y.-H.

Eksploatacja i Niezawodność

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2015

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Vol. 17, no. 2

199--206

EN

The failure behaviors of many real-life systems are very complex and sequence-dependent, and can be modeled by highly-coupled dynamic fault trees (DFTs). Existing approaches for solving DFTs, such as Markov state-space-based or inclusion-exclusion based methods all have their disadvantages. They either suffer from the problem of state space explosion or are subjected to the combination explosion. Additionally, Markov-based approaches become unavailable when components follow non-exponential time-to-failure distributions which prevail in real-life systems. To overcome shortcomings of the methods mentioned above, SFRs (Sequence Failure Regions)-Based numerical simulation approach is first proposed. The proposed method is applicable for a generalized cut sequence as well as highly-coupled DFTs modeling non-repairable systems with arbitrary time-to-failure distributed components. The results of the validation example indicate the reasonability of our proposed approach.

PL

Zachowania uszkodzeniowe wielu działających w rzeczywistości układów są bardzo złożone i zależą od sekwencji w jakiej występują uszkodzenia. Zachowania takie można modelować za pomocą silnie sprzężonych dynamicznych drzew błędów (DFT). Istniejące podejścia do rozwiązywania DFT, takie jak metody markowowskie oparte na pojęciu przestrzeni stanów i metody oparte na zasadzie włączeń i wyłączeń mają swoje ograniczenia:albo borykają się z problemem eksplozji przestrzeni stanów albo są narażone na eksplozję kombinatoryczną. Dodatkowo, podejścia markowowskie stają się niedostępne, gdy elementy składowe mają niewykładnicze rozkłady czasu do uszkodzenia, co ma miejsce w przeważającej części układów spotykanych w rzeczywistości. Aby przezwyciężyć mankamenty powyższych metod, zaproponowano metodę symulacji numerycznej opartą na pojęciu zakresów uszkodzeń sekwencyjnych (sequence failure regions, SFR). Proponowana metoda znajduje zastosowanie w modelowaniu systemów nienaprawialnych o elementach, które charakteryzuje arbitralnie przyjęty rozkład czasu do uszkodzenia. Metodę można stosować w modelowaniu opartym zarówno na uogólnionej sekwencji niezdatności (generalizedcut sequence), jak również silnie sprzężonych DFT. Wyniki uzyskane w przedstawionym przykładzie potwierdzają zasadność proponowanego przez nas podejścia.

12

Optimization of Neural Network Model Design: An Electoral Cooperative Particle Swarm Optimization Approach

Li D., Xu H.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

165--167

EN

This paper proposes an electoral cooperative particle swarm optimization approach to optimize the model of neural network from both structure and linked weights. Different with other related research work, a new encoding method is adopted to divide the neural network into several modules, each of them corresponding to a sub-swarm. Based on the experiments on typical problems and classic dataset, the results show that the proposed algorithm outperforms all the compared ones in perspective of test error, correctness, connection number, and the CPU time of the training phase.

PL

W przedstawionym artykule opisano zastosowanie metod optymalizacji roju cząstek do optymalizacji struktury i współczynników wagowych sieci neuronowej. Zaimplementowano nową metodę analizy, do dzielenia podzielenia sieci na moduły, reprezentujące mniejsze roje. Weryfikacja eksperymentalna i porównanie z metodami klasycznymi wykazały wysoką sprawność i skuteczność analizy.

13

Extended CPHD Filter for Combining Multi-Target Tracking with Sensor Alignment

Li D., Yi D.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

41--44

EN

An extended CPHD (Cardinalised Probability Hypothesis Density) filter for combining multi-target tracking with sensor alignment is proposed. The augmented state is established by appending the sensor biases to the single-target state. The cardinality distribution of the targets and the intensity of the augmented state are propagated by employing Gaussian mixtures. The target states and the sensor biases are jointly estimated. Simulation results show that the proposed filter successfully achieves the sensor alignment and outperforms the standard CPHD filter.

PL

Zaproponowano rozszerzony filtr CPHD do połączenia śledzenia wielu celów z wyrównaniem czujników. Wyrażenia dotyczące pojedynczego celu rozszerzono przez dodanie offsetu czujnika. Moc (kardynalność) rozkładu celów i intensywność rozszerzonego wyrażenia są zrealizowane przez zastosowanie przekształceń Gaussa. Przeprowadzono jednoczesna estymację wyrażeń celu i offsetu czujnika. Wyniki symulacji wykazują, że proponowane rozwiązanie satysfakcjonująco dokonuje wyrównania czujników i wyjściowych parametrów standardowego filtru CPHD.

14

An electoral quantum-behaved PSO with Lévy flights for permutation flow shop scheduling problem

Li D., Deng N.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

138--142

EN

Permutation flow shop scheduling problem (PFSSP), a NP-hard combinatorial optimization problem, has strong engineering background of finding the optimal processing sequence and time of jobs on machines under the constraints of resources. Recently, several approaches based on Particle Swarm Optimization (PSO) have been developed to solve the PFSSP, and the experimental results show that they are efficient. To solve this issue, a novel variant of quantum-behaved particle swarm optimization algorithm for permutation flow shop scheduling is proposed in this paper. This algorithm is a combination of quantum-behaved PSO, electoral mechanism, and a disturbance generated by Lévy flights. Inspired by the election behavior in society, an electoral and cooperative mechanism is imported to get the elite particles from the primitive sub-swarms respectively. Moreover, the character unequal hop length of Lévy flights provides a method to escape the local optima efficiently. The numerical results on the Taillard's benchmark also show it outperforms other related algorithms.

PL

Problem szeregowania zmiany przepływów magazynowych (PFSSP) jest silnie nie–wielomianowym (NP) problemem optymalizacji kombinatorycznej. Ma ważny inżynierski aspekt w wyznaczaniu optymalnej kolejności procesu i czasu pracy maszyn, wymuszonej zmianą zasobów. Ostatnio, do rozwiązania PFSSP, zastosowano szereg przybliżeń opartych o algorytm optymalizacji rojem cząstek (PSO) a wyniki praktyczne pokazują, że są to rozwiązania efektywne. W prezentowanym opracowaniu, do szeregowania przepływów magazynowych, zaproponowano nowy wariant algorytmu optymalizacji rojem cząstek z zachowaniem kwantowym (QPSO). Algorytm jest kombinacją QPSO, mechanizmu wyborczego i zakłóceń generowanych rozkładem lotów Levy’ego. Do wyłonienia cząstek elitarnych z prymitywnego pod-roju wykorzystano, inspirowany zachowaniami wyborczymi w społeczeństwie, mechanizm wyborczy i współpracy. Ponadto, unikalny charakter długości skoków lotów Levy’ego pozwala skutecznie uniknąć optimów lokalnych. Wyniki numeryczne, przeprowadzone na danych testowych Taillard’a, także wskazują na przewagę nad innymi porównywalnymi algorytmami.

15

A hybrid cooperative quantum particle swarm optimizer with dynamic varying search area for function optimization

Li D.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 3b

21--24

EN

This paper proposes a hybrid cooperative quantum particle swarm optimization (HCQPSO), hybridizing dynamic varying search area, cooperative evolution, simulated annealing and quantum particle swarm optimization (PSO) for function optimization. In the proposed HQCPSO, a technique of dynamic varying search area helps reduce the search spaces and populations of swarms, which could make the optimization more efficient. Simulated annealing is integrated in the position update to modify the trajectories of particles to avoid being trapped in the local optimum. To test the performance of HQCPSO, numerical experiments are conducted to compare the proposed algorithm with different variants of PSO. According to the experimental results, the proposed method performs better than other variants of PSO on benchmark test functions.

PL

W artykule zaproponowano hybrydowy algorytm optymalizacji PSO. Porównanie z innymi, znanymi wariantami wykazało, że zastosowane w metodzie rozwiązania, pozwalają na efektywniejsze działanie proponowanego algorytmu PSO. Wyniki eksperymentalne potwierdziły powyższą tezę.

16

Granular Computing Based on Gaussian Cloud Transformation

Liu Y., Li D., He W., Wang G.

Fundamenta Informaticae

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2013

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Vol. 127, nr 1-4

385--398

EN

Granular computing is one of the important methods for extracting knowledge from data and has got great achievements. However, it is still a puzzle for granular computing researchers to imitate the human cognition process of choosing reasonable granularities automatically for dealing with difficult problems. In this paper, a Gaussian cloud transformation method is proposed to solve this problem, which is based on Gaussian Mixture Model and Gaussian Cloud Model. Gaussian Mixture Model (GMM) is used to transfer an original data set to a sum of Gaussian distributions, and Gaussian Cloud Model (GCM) is used to represent the extension of a concept and measure its confusion degree. Extensive experiments on data clustering and image segmentation have been done to evaluate this method and the results show its performance and validity.

17

A version of cooperative multi-swarm PSO using electoral mechanism to solve hybrid flow shop scheduling problem

Li D., He Q.

Przegląd Elektrotechniczny

|

2012

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R. 88, nr 5b

22-26

EN

Hybrid flow shop (HFS) scheduling problem is a kind of scheduling consisted of a series of stages, in which there exist more than one parallel machine. In this paper, we propose a meta-heuristics using a version of cooperative multi-swarm PSO algorithm for the HFS with minimum makespan objective. The main contribution of this algorithm is to import an electoral mechanism to accelerate the converging and a disturbance approach to help escape from local optima. Finally, experiments show that the algorithm outperforms all the compared in the HFS problem.

PL

W artykule zaproponowano nowy rojowy algorytm do rozwiązywania problemu w harmonogramie dostępu typu HFS. Nowy mechanizm wyboru pozwala na przyśpieszenie konwergencji.

18

Modelowanie i symulacja zabezpieczenia materiałowego jednostki bojowej ukierunkowanego na realizację misji

Li D., Yu Y., Zhang L., Zhang Y.

Eksploatacja i Niezawodność

|

2010

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nr 2

51-54

PL

W artykule przedstawiamy ramy modelowania i symulacji ukierunkowanego na realizację misji Systemu Zabezpieczenia Materiałowego Jednostki Bojowej (Combat Unit Material Support System, CUMSS). Opisujemy proces zabezpieczania materiałowego, analizujemy jego charakterystyki i optymalizujemy zasoby. Prezentowany model opiera się na obszernej analizie procesu eksploatacji oraz procesu wykorzystania zasobów. Skonstruowano strukturę federacyjną i model obiektowy federacji dla zabezpieczenia materiałowego jednostki bojowej. Przedstawiono, na podstawie przykładowej misji, federacje dla zdarzeń dyskretnych, zdarzeń ciągłych i procesu podejmowania decyzji. Do analizy charakterystyk CUMSS w przedstawionym przykładzie misji użyto symulacji.

EN

In this paper, we present a framework for modeling and simulation of a mission-oriented Combat Unit Materiel Support System (CUMSS). We describe the process of materiel support, analyze its performance, and optimize the resources. This model is based on a comprehensive analysis of the maintenance process and the resource utilization process. A federation framework and a federation object model are constructed for combat unit materiel support. For an example, mission, we provide the federations for the discrete events, the continuous events, and the decision-making process. Simulation is used to analyze the performance of CUMSS for this example mission.

19

Structure, magnetic and electrical transport properties of Mn4-xAgxN compounds

Feng W. J., Li D., Zhang Q., Deng Y. F., Ma S., Zhang Z. D.

Materials Science Poland

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2009

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Vol. 27, No. 1

33--42

EN

Mn4-xAgxN compounds (x = 0.0, 0.3, 0.6, 1.0) were prepared by milling and subsequently annealing the mixture of Mn2N0.86, Mn, and Ag powders. All compounds display good single-phase characteristics. Both Mn4N and Mn3.7Ag0.3N exhibit ferrimagnetism, and a little Ag replacement of Mn can improve the saturation magnetization. The magnetic transition of Mn3.4Ag0.6N and Mn3AgN below 15 K is from triangular antiferromagnetism to non-coplanar ferrimagnetism, while the ones at 256 and 275 K (Mn3.4Ag0.6N and Mn3AgN, respectively) have been ascribed to the gradual transition, as temperature increases, from the triangular antiferromagnetic structure T5g to a ferrimagnetic-like one. Two minima appear on the p(T) curves for Mn3AgN, with the observation of a positive magnetoresistance throughout the whole tempeature-dependent change.

20

Construction of the master sintering curve for submicron size A-Al2O3 based on non-isothermal sintering containing lower heating rates only

Shao W., Chen S., Li D., Cao H., Zhang S.

Materials Science Poland

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2009

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Vol. 27, No. 1

97--107

EN

The master sintering curve (MSC) is quite useful for analyzing the shrinkage behaviour of ceramics. In this study, the shrinkage behaviour for ?-Al2O3 with a mean particle size of 350 nm during constantheating- rate sintering were evaluated based on the MSC theory. An MSC for the above powder has been constructed using dilatometry data containing heating rates lower than 5 °C/min only with the help of combined-stage sintering model. The validity of the MSC has been verified by a few experimental runs. A comparison between predicted and experimental shrinkage curves showed good consistency, thus confirming that it is possible to control shrinkage behaviour using the MSC. The concept of the MSC has been used to evaluate the apparent activation energy for the above powder, and a high value of 1035 kJ/mol was obtained.