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1

Edge Effects on Tree Growth and Species Diversity in Forests of Different Types and Ages

Li J., Zhao C., Peng Y., Hu Y., Yuan X.

Polish Journal of Ecology

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2018

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Vol. 66, nr 3

239--249

EN

Edge to interior gradients in forest ecosystems can influence the species composition and community structure as a result of variations in micro-environment. In this study, the edge effects on stand productivity and plant species diversity were investigated in two adjacent types of forests in central-southern China: Chinese fir adjacent with pine forests and Chinese fir adjacent with broad-leaved forests. A total of 48 sample plots for overstory and 240 sample quadrates for understory in different stand ages were set up. The tree growth parameters were measured in the overstory while the plant species diversity was measured in both overstory and understory of the examined forests. The results showed that DBH (tree diameter at the breast height), tree height and stand volume in overstory increased from the central areas (CA) of forests to the edge areas (EA), and the plant species richness and diversity in understory were greater in EA than in CA. The edge effect was greater in Chinese fir paired with broad-leaved forests than in Chinese fir paired with pine forests. The edge effect decreased in an order as young aged stands > middle aged stands > mature aged stands in the studied forests. The changes in tree growth and species diversity in the edge area compared to the interior were mainly attributed to the alteration of micro-environmental factors such as light density, temperature and moisture. Our results suggest increasing forest productivity and plant species diversity could be achieved by making more edges in the forests.

2

Quartz enhanced photoacoustic spectroscopy based on an external cavity quantum cascade laser

Xu L., Zhou S., He T., Li J.

Optica Applicata

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2018

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Vol. 48, nr 4

687--695

EN

Mid-infrared laser spectroscopy is a powerful analytical tool for trace gases detection. In this study, a spectroscopic system based on an external cavity quantum cascade laser (ECQCL) and quartz enhanced photoacoustic spectroscopy (QEPAS) was developed for volatile organic compounds (VOCs) measurements. Primary laboratory test on ethanol spectroscopy was investigated and compared with traditional direct absorption spectroscopy (DAS). Experimental results show that the proposed QEPAS is more sensitive than the conventional DAS method. In addition, the significant linear dependence of photoacoustic signal on sample pressures and laser operating parameters was observed.

3

A polarization filter at 1550 nm based on photonic crystal fiber with symmetry around gold-coated holes

Zha F., Li J., Sun P., Wang X.

Optica Applicata

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2018

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Vol. 48, nr 4

609--620

EN

A polarization photonic crystal fiber based on surface plasmon resonance is proposed in this paper. The photonic crystal fiber with gold coated holes is studied through using the finite element method. The impacts of structural parameters on the resonance characteristics are discussed. Numerical simulations show that the resonance wavelength can be modulated by changing the parameters of the air holes and thickness of gold layer. At the resonance wavelength 1550 nm, the loss is 3.8045 dB/m in x-polarization and the loss is 28464 dB/m in y-polarization by adjusting the size of the gold-coated holes and the place of air holes. Results show that the loss of y-polarized mode is much larger than the loss of x-polarized mode. The y-polarized mode is suppressed, and only x-polarized mode can be guided at the resonance wavelength of y-polarized mode. The results indicate that the mode polarized in one direction can be filtered out selectively by adjusting the diameter of air holes, and the filtering effect in a communication band is achieved.

4

Primary parametric resonance of an axially accelerating beam subjected to static loads

Hu Y., Rong Y., Li J.

Journal of Theoretical and Applied Mechanics

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2018

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Vol. 56 nr 3

815--828

EN

Primary parametric resonance and stability of an axially accelerating and current-carrying beam subjected to static loads in magnetic ﬁeld are investigated. The nonlinear magneto-elastic vibration equation is derived. The approximate solution of the static problem and the disturbance deferential equation of the beam with two sides simply supported are obtained. The frequency-response equation of primary parametric resonance is further achieved by a multi-scale method. According to stability conditions, the stability of the steady-state solution is also discussed. By numerical examples, the amplitude versus diﬀerent parameter curves and the bifurcation diagrams of the amplitude are acquired. The eﬀects of magnetic induction intensity, axial speed, detuning parameter and static loads on nonlinear vibration characteristics are also analyzed.

5

Star-Topological Encryption : Talking to the Sever but Hiding Identities to Others

Li J., Wang L., Niu X., Gu L., Qu Z.

Fundamenta Informaticae

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2018

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Vol. 157, nr 1/2

29--46

EN

In this paper, we propose the notion of Star-Topological encryption that enables some clients confidentially talking to a server but without revealing their identities to others. Then, an encryption scheme is constructed to achieve this cryptosystem based on non-abelian groups. The proposal realizes identity-based encryption and identity authenticity, simultaneously. In this encryption system, both the encryptions and decryptions of two sides of the communications are relying on secret key. Therefore, the encryption/decryption algorithms employ the idea of symmetric key cryptosystem. Meanwhile, the client’s decryption key is generated by taking client’s identity and server’s master secret key as input. Therefore, our encryption scheme can be viewed as an identity-based encryption in Symmetric Key Cryptosystem. Furthermore, the security of the scheme is based on the intractability of factorization search problem over non-abelian algebraic structures. A matrix group over group ring is suggested and an algorithm of computing the inverse of an invertible group ring element is given. Finally, we discuss that our cryptosystem is secure against determinant attacks and quantum attacks.

6

Cryptanalysis and Improvement for Certificateless Aggregate Signature

Li J., Yuan H., Zhang Y.

Fundamenta Informaticae

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2018

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Vol. 157, nr 1/2

111--123

EN

In order to satisfy application in resource constrained environment, aggregate signature schemes have been widely investigated. Recently, He et al. pointed out that certificateless aggregate signature (CLAS) scheme proposed by Xiong et al. was insecure against the Type II adversary and presented an possible improvement. In this article, we show that their improved scheme is not secure against a malicious-but-passive KGC attack. We analyze attack reason and propose an improved certificateless aggregate signature scheme. Based on the CDH difficult problem assumption, the proposed CLAS scheme is existentially unforgeable against adaptive chosen-message attacks in the random oracle model.

7

An Efficient Construction of Quantum Attack Resistant Proxy Re-Encryption Based on (Semi) group Factorization Problems

Wang L., Li J., Gu L., Yan J., Qu Z.

Fundamenta Informaticae

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2018

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Vol. 157, nr 1/2

47--62

EN

Proxy re-encryption (PRE) enables a semi-trusted proxy to transfer Alice's secrets into Bob's secrets but without seeing the secrets. This functionality is very interesting for making balance between the information confidentiality and the mutual accessibility in various scenarios such as public cloud storage systems. During the past decades, many smart PRE schemes were built based on intractability assumptions such as integer factorization problems (IFP) and discrete logarithm problems (DLP). However, Shor's efficient quantum algorithms for IFP and DLP stand great threats towards the security baseline of these schemes. Enlightened by Gu et al.'s recent work on resisting known quantum attacks, we propose an efficient PRE scheme based on the intractability of the (semi)group factorization problems in this paper. The security of the proposed scheme is analyzed according to some heuristic attacks. Moreover, a special instantiation technique is present in detail, and some illustrations are provided for manifesting the effectiveness and efficiency of the proposed methodology.

8

Evaluation on gas supply reliability of urban gas pipeline network

Li J., Yan M., Yu J.

Eksploatacja i Niezawodność

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2018

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Vol. 20, no. 3

471--477

EN

As one of the lifeline projects, an urban gas network is a complex system, as it requires maintenance of the supply capacity when any single pipeline is isolated due to failure. For such a system, its reliability needs to be evaluated. Considering that existing structural reliability and hydraulic reliability analyses reflect different aspects of the working conditions of an urban gas network, system reliability theory is employed to explain that only the gas supply reliability can achieve a comprehensive evaluation of the work capacity of the entire urban gas network, as it takes into account the combined influence of the structural reliability and hydraulic reliability. To calculate the parameters in the gas supply reliability evaluation, such as pipeline failure rate, flow reduction in the gas network under different failure conditions, etc., some research achievements in the field of structural reliability and hydraulic reliability are fully utilized. Then, the detailed calculation procedures of these parameters are given to evaluate the gas supply reliability in terms of operational and practical considerations. Finally, using an example of a simple double-loop gas network, the detailed process of the gas supply reliability evaluation of an urban gas network is described, and the feasibility of this evaluation method is also illustrated.

PL

Miejska sieć gazowa – jeden z kluczowych elementów infrastruktury miasta – stanowi złożony system, ponieważ wymaga utrzymania zdolności przesyłowej gdy przepływ gazu w jednym z rurociągów zostaje zamknięty w wyniku awarii. W przypadku tego rodzaju systemów, konieczna jest ocena niezawodności. Biorąc pod uwagę, iż dostępne w literaturze analizy niezawodności konstrukcyjnej i niezawodności hydraulicznej odzwierciedlają różne aspekty warunków pracy miejskiej sieci gazowej, nie dają one pełnego obrazu niezawodności systemu jako całości. W artykule wykorzystano teorię niezawodności systemów, która pokazuje, że jedynie ocena niezawodności dostaw gazu stanowić może kompleksową ocenę wydajności pracy całej miejskiej sieci gazowej, ponieważ uwzględnia ona zarówno wpływ niezawodności konstrukcji jak i niezawodności hydraulicznej sieci. W pracy wykorzystano dotychczasowe obserwacje badawcze dotyczące oceny niezawodności konstrukcyjnej i niezawodności hydraulicznej sieci gazowej do obliczenia parametrów oceny niezawodności dostaw gazu, takich jak intensywność uszkodzeń rurociągu, redukcja przepływu gazu w sieci gazowej w różnych warunkach uszkodzeń, itp. Następnie, podano szczegółowe procedury obliczania tych parametrów w celu oceny niezawodności przesyłowej sieci gazowej pod kątem eksploatacyjnym i praktycznym. Na koniec, na przykładzie prostej sieci gazowej składającej się z dwóch pętli, opisano szczegółowy proces oceny niezawodności dostaw gazu w miejskiej sieci gazowej i zilustrowano możliwość wykorzystania proponowanej metody.

9

Dynamic diagnostic strategy based on reliability analysis and distance-based VIKOR with heterogeneous information

Li J., Duan R.

Eksploatacja i Niezawodność

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2018

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Vol. 20, no. 4

610--620

EN

This paper presents a dynamic diagnostic strategy based on reliability analysis and distance-based VIKOR with heterogeneous information. Specifically, the proposed method uses a dynamic fault tree (DFT) to describe the dynamic fault characteristics and evaluates the failure rate of components using interval numbers to deal with the epistemic uncertainty. Furthermore, DFT is mapped into a dynamic evidential network (DEN) to calculate some reliability parameters and these parameters together with test cost constitute a decision matrix. In addition, a dynamic diagnostic strategy is developed based on an improved VIKOR algorithm and the previous diagnosis result. This diagnosis algorithm determines the weights of attributes based on the Entropy concept to avoid experts’ subjectivity and obtains the optimal ranking directly on the original heterogeneous information without a transformation process, which can improve diagnosis efficiency and reduce information loss. Finally, the performance of the proposed method is evaluated by applying it to a train-ground wireless communication system. The results of simulation analysis show the feasibility and effectiveness of this methodology.

PL

W artykule przedstawiono dynamiczną strategię diagnostyczną, w której wykorzystuje się oryginalne informacje heterogeniczne. Metoda ta bazuje na analizie niezawodności i opartym na odległościach algorytmie VIKOR. Dokładniej, przedstawiona strategia polega na wykorzystaniu dynamicznego drzewa błędów (DFT) do opisu dynamicznych charakterystyk błędów oraz ocenie intensywności uszkodzeń komponentów przy użyciu liczb przedziałowych, co pozwala rozwiązać problem niepewności epistemicznej. Ponadto, w proponowanej metodzie, DFT zostaje odwzorowane w dynamiczną sieć dowodową (DEN) w celu obliczenia niektórych parametrów niezawodności, a parametry te wraz z kosztem badań diagnostycznych tworzą matrycę decyzyjną. Opracowana dynamiczna strategia diagnostyczna opiera się na udoskonalonym algorytmie diagnostycznym VIKOR oraz wynikach wcześniejszej diagnostyki. Algorytm VIKOR określa wagi atrybutów w oparciu o koncepcję Entropii, co pozwala wyeliminować subiektywność oceny eksperckiej i ustalić optymalną kolejność działań diagnostycznych bazując bezpośrednio na oryginalnych informacjach heterogenicznych bez konieczności ich transformacji, co może poprawić efektywność diagnozy i zmniejszyć utratę informacji. Działanie proponowanej metody oceniano poprzez zastosowanie jej do diagnostyki systemu łączności radiowej pociąg–ziemia. Wyniki analizy symulacyjnej wskazują na możliwość praktycznego wykorzystania i skuteczność omawianej metodologii.

10

Vehicle routing problem with partly simultane-ous pickup and delivery for the cluster of small and medium enterprises

He P., Li J.

Archives of Transport

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2018

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Vol. 45, iss. 1

35--42

EN

The transportation service for the cluster of small and medium enterprises (SMEs) is different with traditional vehicle routing problems. In the cluster of SMEs, parts of enterprises are pickup and delivery spots simultaneously, but some enterprises are partly pickup and delivery simultaneously. It is necessary to optimize this transportation service with an effective mathematics and algorithm to reduce transportation costs for manufacturers. However, traditional mathematics models and algorithms are not suitable to solve the vehicle routing problem partly simultaneous pickup and delivery (VRPPSD) because these items mainly focus on the vehicle routing problem with pickup and delivery simultaneously. In this paper, a mathematics operational model is proposed to analyze the transportation service of the cluster companies and to describe transportation processes. A hybrid algorithm which is composed by tabu search, genetic algorithm and local search is used to optimize the operational model. The crossover and mutation contained by genetic algorithm are used to generate neighborhood solutions for tabu search, and the local search is used to improve optimizing solutions. The data of a cluster of SMEs, investigating from Changzhou city, China, are employed to show the validity of our mathematical model and algorithm. The results indicate that our model and hybrid algorithm is effective to solve VRPPSD. In this paper, the satisfied solutions of VRPPSD are found by hybrid algorithm. At the same time, the results also show that carriers with optimal routs can service customers with more profits (increasing 5.6%). The potential saving of transport cost will increase profits of carriers in SMEs. Sensitivity analyses about adjusting service time and rate of new orders are lunched to analyze how these two factors influence the profits of the VRPPSPD in a dynamic case. A bottleneck that influences the profits is found, and there has a shorter service time which could increase gross profits, but not significantly.

11

Półciągła beztlenowa kofermentacja obornika świńskiego i krowiego w produkcji biogazu

Li J., Wei L., Duan Q., Zhang G., Li S., Kong C.

Przemysł Chemiczny

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2017

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T. 96, nr 10

2145--2151

PL

Określono parametry półciągłej beztlenowej kofermentacji obornika świńskiego (OŚ) i obornika krowiego (OK) zmieszanych w 5 proporcjach masowych (OŚ/OK). W procesie wyróżniono 3 etapy: rozruch, produkcję gazu oraz zatrzymanie procesu. Dużą zawartość metanu w biogazie (ok. 64%) i małą zawartość części lotnych (ok. 34%) uzyskano dla mieszaniny o proporcji OŚ/OK 5:5. Przy proporcjach OŚ/OK 7:3 i 9:1 uzyskano dużą produktywność biogazu, odpowiednio 0,56 L/(L·d) oraz 0,63 L/(L·d). Mieszaniny OŚ/OK 1:9 i 3:7, z produktywnością gazu ok. 0,42 L/(L·d), okazały się najmniej korzystne w całym procesie. Analiza elementarna wykazała początkową zawartość węgla (27-30%), fosforu (0,7-0,8%) i żelaza (0,29-0,35%) w surowcu. Stosunek OŚ/OK 7:3 zwiększył fermentację biogazu, a akumulacja azotu i fosforu spowodowała zahamowanie fermentacji.

EN

Pig and cattle manures were mixed in mass ratio 1:9 to 9:1 and cofermented to biogas under lab. conditions (bioreactor volume 800 mL) for 47 days after addition of municipal sewage as inoculum. A high MeH content (about 64%) in biogas was reached for the ratio of manures 5:5 while high biogas productivity was obtained at the ratios 7:3 and 9:1.

12

Multi-AUV distributed task allocation based on the differential evolution quantum bee colony optimization algorithm

Li J., Zhang R.

Polish Maritime Research

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2017

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S 3

65--71

EN

The multi-autonomous underwater vehicle (AUV) distributed task allocation model of a contract net, which introduces an equilibrium coefficient, has been established to solve the multi-AUV distributed task allocation problem. A differential evolution quantum artificial bee colony (DEQABC) optimization algorithm is proposed to solve the multi-AUV optimal task allocation scheme. The algorithm is based on the quantum artificial bee colony algorithm, and it takes advantage of the characteristics of the differential evolution algorithm. This algorithm can remember the individual optimal solution in the population evolution and internal information sharing in groups and obtain the optimal solution through competition and cooperation among individuals in a population. Finally, a simulation experiment was performed to evaluate the distributed task allocation performance of the differential evolution quantum bee colony optimization algorithm. The simulation results demonstrate that the DEQABC algorithm converges faster than the QABC and ABC algorithms in terms of both iterations and running time. The DEQABC algorithm can effectively improve AUV distributed multi-tasking performance.

13

Significance of Stump-Sprouting for the Population Size Structure and Spatial Distribution Patterns of Endangered Species, Magnolia cylindrical

Li J., Wu Y., Wu T., Cao L., Chen J., Qiu Z., Zhang Y., Xu G., Zhang J., Liu P.

Polish Journal of Ecology

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2017

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Vol. 65, nr 2

247--257

EN

Magnolia cylindrica Wils. is one of the third most-protected wild plants in China. To describe the size structure and dynamics of its population, field data were obtained from eight newly established sites, using a contiguous grid quadrate method in Jiulong Mountain of East China. The population size structure and spatial distribution pattern were discussed based on a theoretical distribution model and assembling intensity index. The population size structure showed a declining trend because of the lack of seedlings. The number of stump-sprouting, size class III (sapling trees) individuals was large enough to make up for the shortage of small seedlings and the complete regeneration of populations through sprouting. The distributions of M. cylindrica, both seedling populations (Group A) and overall populations (Group B), were mostly clumped. The spatial pattern intensities of the populations at different stages (mainly small trees, middle trees, and big trees) were higher for Group A than those for Group B. The two groups have the same tendency in that the pattern intensity declined from small trees to the larger ones. Group A and Group B differed in spatial pattern: small and middle trees were randomly distributed in seedling populations, but aggregated in overall populations. The populations of M. cylindrica (both group A and B) were characterized by the pattern scale between 16 to 32 m2, measured by Greig-Smith and Kershaw methods. These results suggest that sprouting should be seriously considered in population rehabilitation and forest tending management and the area of forest tending management should be close to the maximum intensity.

14

Ultrashort pulse propagation recording by using the transmission-type light in flight holography

Fan Y., Li J., Zheng S., Lu X., Zhong X.

Optica Applicata

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2017

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Vol. 47, nr 2

283--294

EN

In this paper, the distortion of the reconstructed images of the propagating light pulse in transmission light-in-flight holography recording was analyzed. Based on the analysis model, for recording the wavefront more accurately, the optimized selection of relevant parameters was made. Furthermore, a cylindrical lens was introduced to correct the image distortion. Additionally, the light-in-flight recording of the wavefront changing during propagation was simulated.

15

Dynamic evolution of mixed circular edge-screw dislocations

Gao P., Li J., Cheng K., Duan M.

Optica Applicata

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2017

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Vol. 47, nr 3

471--481

EN

Based on the extended Huygens–Fresnel principle, the analytical expressions for the cross-spectral density function of mixed circular edge-screw dislocations beams propagating through atmospheric turbulence have been derived, and used to study the dynamic evolution of mixed circular edge-screw dislocations in free space and atmospheric turbulence. It is shown that the radius of circular edge dislocations increases with increasing propagation distance, and both the positions of the optical vortex and the center of circular edge dislocations are located at the point (0, 0) when mixed circular edge-screw dislocations propagate in free space. When mixed circular edge-screw dislocations propagate in the atmospheric turbulence, the position of optical vortices varies with increasing propagation distance, the circular edge dislocation evolves into a pair of optical vortices with the opposite topological charge ±1, and the pair of optical vortices will annihilate as soon as the propagation distance becomes large enough.

16

Compressive optical image encryption using phase-shifting interferometry on a joint transform correlator

Li J., Jia B., Dai X., Lei M., Yang C., Li J., Li H., Li R.

Optica Applicata

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2017

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Vol. 47, nr 2

245--256

EN

A compressive optical image encryption method, which combines compressive sensing with phase-shifting interferometry on a joint transform correlator, is proposed in the fully optical domain. The object image is first permutated using a binary scrambling method. Next, the permutated object field is encrypted and registered as the holograms by phase-shifting interferometry on the joint transform correlator setup. Then, the encrypted images and the key are compressed to the compressed data using single-pixel compressive imaging. The original image can be reconstructed and decrypted using the specified algorithm. The simulations demonstrate that the method is effective and suitable for image security transmission.

17

Changes in the states of polarization of random electromagnetic beams in atmospheric turbulence

Li J., Zhao K., Lai Y.

Optica Applicata

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2017

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Vol. 47, nr 1

51--62

EN

Taking the random electromagnetic cosh-Gaussian beam as a typical example of random electromagnetic beams, the analytical expressions for the cross-spectral density matrix element of random electromagnetic cosh-Gaussian beams propagating through non-Kolmogorov atmospheric turbulence are derived, and used to study the changes in the states of polarization (degree of polarization, orientation angle and degree of ellipticity) of random electromagnetic cosh-Gaussian beams in non-Kolmogorov atmospheric turbulence. It is shown that the states of polarization of random electromagnetic cosh-Gaussian beams in non-Kolmogorov atmospheric turbulence are different from those in free space. The degree of polarization decreases, and the orientation angle and degree of ellipticity increase with increasing structure constant. The on-axis degree of polarization and the degree of ellipticity appear to have an oscillatory behavior and the orientation angle has a rapid transition for the larger cosh-part parameter of random electromagnetic cosh-Gaussian beams in atmospheric turbulence.

18

Calibration of backward-in-time model using drifting buoys in the East China Sea

Yu F., Li J., Zhao Y., Li Q., Chen G.

Oceanologia

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2017

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No. 59 (3)

238--247

EN

In the process of oil exploitation and transportation, large amounts of crude oil are often spilled, resulting in serious pollution of the marine environment. Forecasting oil spill reverse trajectories to determine the exact oil spill sources is crucial for taking proactive and effective emergency measures. In this study, the backward-in-time model (BTM) is proposed for identifying sources of oil spills in the East China Sea. The wind, current and random walk are three major factors in the simulation of oil spill sources. The wind drag coefficient varies along with the uncertainty of the wind field, and the random walk is sensitive to various traits of different regions, these factors are taken as constants in most of the state-of-the-art studies. In this paper, a self-adaptive modification mechanism for drift factors is proposed, which depends on a data set derived from the drifter buoys deployed over the East China Sea shelf. It can be well adapted to the regional characteristics of different sea areas. The correlation factor between predicted positions and actual locations of the drifters is used to estimate optimal coefficients of the BTM. A comparison between the BTM and the traditional method is also made in this study. The results presented in this paper indicate that our method can be used to predict the actual specific spillage locations.

19

An improved Otsu method for oil spill detection from SAR images

Yu F., Sun W., Li J., Zhao Y., Zhang Y., Chen G.

Oceanologia

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2017

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No. 59 (3)

311--317

EN

In recent years, oil spill accidents have become increasingly frequent due to the development of marine transportation and massive oil exploitation. At present, satellite remote sensing is the principal method used to monitor oil spills. Extracting the locations and extent of oil spill spots accurately in remote sensing images reaps significant benefits in terms of risk assessment and clean-up work. Nowadays the method of edge detection combined with threshold segmentation (EDCTS) to extract oil information is becoming increasingly popular. However, the current method has some limitations in terms of accurately extracting oil spills in synthetic aperture radar (SAR) images, where heterogeneous background noise exists. In this study, we propose an adaptive mechanism based on Otsu method, which applies region growing combined with both edge detection and threshold segmentation (RGEDOM) to extract oil spills. Remote sensing images from the Bohai Sea on June 11, 2011 and the Gulf of Dalian on July 17, 2010 are utilized to validate the accuracy of our algorithm and the reliability of extraction results. In addition, results according to EDCTS are used as a comparator to further explore validity. The comparison with results according to EDCTS using the same dataset demonstrates that the proposed self-adapting algorithm is more robust and boasts high-accuracy. The accuracy computing by the adaptive algorithm is significantly improved compared with EDCTS and threshold method.

20

Effect of electron beam injection on boron redistribution in silicon and oxide layer

Qin S., Tan Y., Li J., Jiang D., Wen S., Shi S.

Materials Science Poland

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2017

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Vol. 35, No. 1

14--17

EN

The behavior of boron redistribution in silicon with and without oxide layer after electron beam injection (EBI) was investigated. Special defect shapes were generated on the surface of bare and oxidized silicon wafers. Secondary ion mass spectrometer was used to measure the boron profile. The results showed that after long EBI time, boron tended to be induced from both sides of the transition region between the oxide layer and silicon. For the sample without oxide layer after EBI, boron tended to diffuse towards the surface and its concentration obviously reduced inside the silicon. The results of the study show the potential use of the process in removing boron impurity in silicon.