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Research on Improved LEACH Protocol of Wireless Sensor Networks

Shan J., Dong L., Liao X., Shao L., Gao Z., Gao Y.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 1b

75--77

EN

This investigation was performed to see if the improved LEACH protocol operates more effectively than the traditional LEACH protocol. The improved protocol adds energy factor and distance factor to the threshold T(n). The multi-hop routing algorithm of cluster head is introduced too, it based on the hop count and the remaining energy. MATLAB was used to simulate. The simulation data suggests that the death rate of nodes of the improved protocol was lower than the traditional one. It is concluded that the improved LEACH protocol can balance network load and extend the life-cycle of network.

PL

Zbadano efektywność pracy udoskonalonego, w stosunku do tradycyjnego, protokołu hierarchicznego klastrowania LEACH. Udoskonalenie protokołu polega na wprowadzeniu współczynników energii i odległości węzłów oraz wykorzystaniu ich przy obliczaniu wartości progowej T(n). Zastosowano również wielo-przeskokowy algorytm klastrowania węzła głównego. Algorytm działa na zasadzie liczenia przeskoków i zachowania energii. Do symulacji wykorzystano program MATLAB. Wyniki symulacji wykazują, że tempo uszkodzeń węzłów przy zastosowaniu udoskonalonego protokołu jest mniejsze niż w przypadku tradycyjnego. Podsumowując, udoskonalony protokół LEACH może zrównoważyć obciążenie i wydłużyć okres życia sieci.

2

Short-Term Wind Power Forecasting with Combined Prediction Based on Chaotic Analysis

Dong L., Gao S., Liao X., Gao Y.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 5b

35-39

EN

With the integration of wind energy into electricity grids, it is becoming increasingly important to obtain accurate wind power forecasts. In this paper, models for short-term wind power prediction in large wind farms are discussed. The analysis of modeling with low dimensions nonlinear dynamics indicates that wind power time series have chaotic characteristics and wind power can be predicted in the short-term. The wind power prediction models are built with phase space reconstruction method and the combination model with different embedding dimensions is tested.

PL

Opisano metodę krótkoterminowego prognozowania mocy elektrowni wiatrowych bazującą na chaotycznym charakterze wiatru w krótkich odstępach czasu.

3

Game-based Decentralized Charging Control for Large Populations of Electric Vehicles

Xie K., Dong L., Liao X., Gao Z., Gao Y.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 7b

252--255

EN

This paper proposes a game-based decentralized charging control strategy for large populations of electric vehicles (EVs). Assuming all EV owners make their own charging strategy according to the electricity price and the total electricity demand of the day before, the owners can be guided to actively participate in the game by a set of electricity pricing mechanism. The existence of Nash equilibrium and the global optimum (or ‘Valley-filling’) of the charging strategy are verified. Simulation results demonstrate the convergence to the Nash equilibrium within a few iterations.

PL

W artykule zaproponowano strategię ładowania dla dużej populacji pojazdów elektrycznych bazująca na teorii gier. Strategia wykorzystuje informacje o cenie energii i prognozowanym zapotrzebowaniu. Zweryfikowano metody optymalizacji.

4

Carbon Footprint of Production Processes of Polypropylene Nonwoven Shopping Bags

Muthu S. S., Li Y., Hu J. Y., Mok P. Y., Liao X.

Fibres & Textiles in Eastern Europe

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2012

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Vol. 20, no. 3 (92)

12--15

EN

This article reports on the carbon footprint of production processes of polypropylene nonwoven shopping bags made out of two different manufacturing technologies (Products A and B, made by the conventional sewing and thermal joining methods) assessed from their cradle to the gate stage using the Life Cycle Assessment (LCA) technique. This study was performed based on the comprehensive Life Cycle Inventory (LCI) of two different manufacturing sequences obtained from a detailed in-field study of the nonwoven PP bag manufacturing industry. The environmental impacts were quantified by means of the IPCC 2007 GWP V 1.1. method in SIMAPRO 7.2. The carbon footprint expressed in terms of the global warming potential (kg CO2 values for 20 and 100 years), calculated by IPCC 2007 methods, was considered as a directive to compare the environmental impact of these bags, manufactured by the two different technologies, and a detailed explanation of the results is provided in this paper. From the results of carbon footprint modelling, product A, made by conventional sewing technology, was found to be better than product B, made by thermal technology. A detailed explanation of the results of the environmental performance of these bags as well as the hot-spots in both production technologies are discussed to a greater extent in this article.

PL

Artykuł dotyczy poziomu emisji związków węgla przy produkcji toreb na zakupy wykonanych z włókniny polipropylenowej przy zastosowaniu dwóch różnych technologii (konwencjonalne szycie i zgrzewanie termiczne) ocenionego techniką LCA - środowiskowej oceny analizy cyklu życia produktu. Badania przeprowadzono w oparciu o wyczerpującą analizę zbioru danych cyklu życia (LCI) dwóch różnych procedur produkcyjnych opartych na zebraniu danych od producentów toreb. Ilościowa ocena wpływu środowiska została wyliczona stosując metodę IPCC 2007 GWP V 1.1. Emisja związków węgla w kategoriach potencjału tworzenia efektu cieplarnianego (wartość kgCO2 podana dla 20 i 100 lat) zastała uznana za istotny czynnik dla oceny wpływu analizowanych procesów produkcyjnych na środowisko. Stwierdzono, że z punktu widzenia emisji korzystniejszy jest tradycyjny sposób produkcji - zszywanie, w porównaniu do zgrzewania.

5

A Digital Image Encryption Algorithm Based on Hyper-chaotic Cellular Neural Network

Peng J., Zhang D., Liao X.

Fundamenta Informaticae

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2009

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Vol. 90, nr 3

269-282

EN

Using Chaotic characteristics of dynamic system is a promising direction to design cryptosystems that play a pivotal role in a very important engineering application of cognitive informatics, i.e., information assurance and security. However, encryption algorithms based on the lowdimensional chaotic maps face a potential risk of the keystream being reconstructed via return map technique or neural network method. In this paper, we propose a new digital image encryption algorithm that employs a hyper-chaotic cellular neural network. To substantiate its security characteristics, we conduct the following security analyses of the proposed algorithm: key space analysis, sensitivity analysis, information entropy analysis and correlation coefficients analysis of adjacent pixels. The results demonstrate that the proposed encryption algorithm has desirable security properties and can be deployed as a cornerstone in a sound security cryptosystem. The comparison of the proposed algorithm with five other chaos-based image encryption algorithms indicates that our algorithm has a better security performance.

6

Triterpenoid Acids from Kadsura ananosma

Chen Y., Song X., Hai N., Fang A, Bi Y., Liao X.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 10

1677-1681

EN

Ananosic acid D, a new 18 (1312) abeo lanostane triterpenoid acid was isolated from the stem barks of Kadsura ananosma and assigned the structure 3-hydroxy-18 (1312) abeo lanost-7 (8), 12 (18), 24 (Z)-trien-26-oic acid (1) by spectroscopic analysis including HR-ESI-MS and 2D-NMR. In addition, known lanostane triterpenoid acids 24(E)-3-oxo- lanosta-8, 24-dien-26-oic acid (2) and anwuweizic acid (3) were also obtained from this species. 2 was obtained as a new natural product and 3 was isolated from the plant for the first time.