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The safe freeway merging operation for fully Autonomous Vehicles (AVs) in mixed traffic (i.e., the presence of AVs and non-AVs in a traffic stream) is a challenging task. Under a mixed traffic environment, an AV merging operation could significantly increase conflict risks and reduce operational efficiency.This study quantifies the freeway merging conflict risk and develops a freeway merging decision strategy based on conflict risk assessment for an AV attempting to merge to a traffic stream with non-AVs on the freeway. The performance of the risk-based merging decision strategy is evaluated in uncongested, near-congested, and congested traffic conditions.The analyses show that the risk-based merging strategy causes less abrupt deceleration of an AV's immediate upstream vehicle in the target lane on the freeway compared to the based models (i.e., two models based on gap acceptance concepts and a safe gap model based on a surrogate measure, 'Time-to-Collision (TTC)'). The risk-based merging strategy meets the minimum safe gap between an AV intending to merge and its immediate downstream vehicle in the target lane. The risk-based merging strategy produces lower conflict risk in terms of 'Time Exposed Time-to-Collision (TET)' and 'Time Integrated Time-to-Collision (TIT)' compared to the base models. Moreover, the risk-based merging strategy has a lower impact on the average speed of traffic in the target lane compared to the base models considered in this study.The risk-based merging strategy shows higher safety benefits for an AV's merging operation compared to base models.The findings of this research would help design AV controllers for improving the safety of an AV merging operation in a mixed traffic stream.

A symmetric–asymmetric hybrid optical encryption and decryption system is proposed based on chaotic cryptography, compressive sensing (CS), and computer-generated holography (CGH). In this system, there are multiple keys, which have the features of both symmetric and asymmetric cryptography. And the biometric code is unique and unchangeable, not easy to be stolen or lost, which further improves the security of the system. Chaos and CS technology can greatly reduce the amount of information. Combined with the advantages of the digitization of CGH, it is conducive to the preservation and transmission of encrypted information. An effective method to further compress information by using spectrum filtering technology is also studied. The simulation results demonstrated that this scheme is feasible and has better security and higher robustness.

Introduction: Reducing the likelihood of freeway secondary crashes will provide significant safety, operational and environmental benefits. This paper presents a method for assessing the likelihood of freeway secondary crashes with Adaptive Signal Control Systems (ASCS) deployed on alternate routes that are typically used by diverted freeway traffic to avoid any delay or congestion due to a freeway primary crash. Method: The method includes four steps: (1) identification of secondary crashes, (2) verification of alternate routes, (3) assessment of the likelihood of secondary crashes for freeways with ASCS deployed on alternate routes and non-ASCS (i.e. pre-timed, semi- or fully-actuated) alternate routes, and (4) investigation of unobserved heterogeneity of the likelihood of freeway secondary crashes. Four freeway sections (i.e., two with ASCS deployed on alternate routes and two non-ASCS alternate routes) in South Carolina are considered. Results and Conclusions: Findings from the logistic regression modeling reveal significant reduction in the likelihood of secondary crashes for one freeway section (i.e., Charleston I-26 E) with ASCS deployed on alternate route. Other factors such as rear-end crash, dark or limited light, peak period, and annual average daily traffic contribute to the likelihood of freeway secondary crashes. Furthermore, random-parameter logistic regression model results for Charleston I-26 E reveal that unobserved heterogeneity of ASCS effect exists across the observations and ASCS are associated with the reduction of the likelihood of freeway secondary crashes for 84% of the observations (i.e., primary crashes). Location of the primary crash on the freeway is observed to affect the benefit of ASCS toward freeway secondary crash reduction as the primary crash’s location determines how many upstream freeway vehicles will be able to take the alternate route. Practical Applications: Based on the findings, it is recommended that the South Carolina Department of Transportation (SCDOT) considers deploying ASCS on alternate routes parallel to freeway sections where high percentages of secondary crashes are found.

Introduction: Adaptive Signal Control System (ASCS) can improve both operational and safety benefits at signalized corridors. Methods: This paper develops a series of models accounting for model forms and possible predictors and implements these models in Empirical Bayes (EB) and Fully Bayesian (FB) frameworks for ASCS safety evaluation studies. Different models are validated in terms of the ability to reduce the potential bias and variance of prediction and improve the safety effectiveness estimation accuracy using real-world crash data from non-ASCS sites. This paper then develops the safety effectiveness of ASCS at six different corridors with a total of 65 signalized intersections with the same type of ASCS, in South Carolina. Results: Validation results show that the FB model that accounts for traffic volume, roadway geometric features, year factor, and spatial effects shows the best performance among all models. The study findings reveal that ASCS reduces crash frequencies in the total crash, fatal and injury crash, and angle crash for most of the intersections. The safety effectiveness of ASCS varies with different intersection features (i.e., AADT at major streets, number of legs at an intersection, the number of through lanes on major streets, the number of access points on minor streets, and the speed limit at major streets). Conclusions: ASCS is associated with crash reductions, and its safety effects vary with different intersection features. Practical Applications: The findings of this research encourage more ASCS deployments and provide insights into selecting ASCS deployment sites for reducing crashes considering the variation of the safety effectiveness of ASCS.

In the United States, transportation agencies across the country are increasingly challenged to deliver projects with greater speed and efficiency. This study evaluated the comprehensiveness of the project development process (PDP) adopted by different states. The authors excluded 10 states from their study because of the lack of available online data. The authors developed a three-step method to assess a PDP’s comprehensiveness, which was informed by reviewing each state’s PDP and related literature. The authors then developed a series of criteria for assessing the comprehensiveness of the PDPs of 40 state Departments of Transportation (DOTs), which was used to amass and analyze that multi-state information to explore individual PDP variations and comprehensiveness. Data analysis indicated a wide variance from state to state in each criterion’s comprehensiveness with a similar comprehensiveness characterizing the PDPs in 20 states. Additionally, the authors conducted an analytic hierarchy process (AHP) to weight the criteria and rank PDP’s comprehensiveness. Through the AHP, PDP components relating to the process were determined as the most important criterion in the hierarchy. Environmental studies/documentation/permits, the number of tasks in PDP flowcharts, and value engineering had the highest weight among the sub-criteria of the PDP components, PDP flowchart, and other improvements, respectively. A case study that produced a list of rankings of the state’s PDP’s comprehensiveness was presented to demonstrate how the evaluation method works. The first five states identified through the AHP were Wisconsin, California, Michigan, Florida, and Georgia.

Based on chaotic biological cryptography and computer-generated holography, a symmetric–asymmetric hybrid encryption and decryption system was proposed. This method has multiple keys, in which two decryption keys are different from the encryption keys. The encryption and decryption system possesses both symmetric and asymmetric key cryptography features. The biometric code is unique and unchangeable, not easy to be stolen or lost, which further enhances the security of the system. Chaos technology can reduce the amount of information, when combined with the advantages of the digitization of computer-generated holography, which can be conducive to the preservation and the transmission of encrypted information. The numerical simulation results show that this scheme is feasible and has better security and higher robustness.

Tuberose is an ornamental plant of economic importance produced worldwide due to the elegant shape and fragrant flowers. Despite its commercial importance, one of the limitations of tuberose production is control of flowering time, which has not been determined at present. In our research, the flowering time has been evaluated in corms of Agave amica cv. Double, during two production cycles (2017 and 2018) using different times of storage of the corms (4, 5, 6 and 7 weeks) at variable temperatures (4 °C, 12 °C, 27 °C, RT). Also, we studied the development of the corms to determine which changes occur in the meristem during floral transition and how the flower quality is affected. The results showed that meristematic differentiation occurred 30-45 days after establishment (DAE) in both culture cycles, although there was no temperature treatment that clearly affected the meristem growth. However, some floral characters were affected, the earliest sprouting occurred in the treatment of six and seven weeks of storage at 27 °C at 20 DAE in 2017 and 10 DAE in 2018, respectively. In addition, the shortest time to flowering occurred in the treatment of seven weeks of storage at 27 °C at 79 days in 2017 and at 100.6 days in 2018, a value that is 30 days earlier than that obtained with the treatments of six weeks of storage at 12 °C, which delayed meristem transition, sprouting and flowering time. In contrast, treatments at 4 °C and GA3 were not statically different from the control in both years.

Objectives. To study the quantification of the components in rat plasma after oral administration of Shenyanyihao oral solution. Methods. Shenyanyihao oral solution has been traditionally used for the treatments of chronic nephritis in clinics. Stachydrine, Danshensu, chlorogenic acid, protocatechuic acid, plantamajoside, aesculetin, isoquercitrin, ferulic acid, baicalin, and baicalein are regarded as the main compounds in Shenyanyihao oral solution. A sensitive, efficient, and precise UPLC-MS/MS method was established and validated for the quantification of the components in rat plasma after oral administration of Shenyanyihao oral solution. Results. The main pharmacokinetic parameters of the components were acquired based on the analysis of the plasma sample by a noncompartmental method using the WinNonlin7.0 pharmacokinetic program. Danshensu, protocatechuic acid, isoquercitrin, and ferulic acid from Shenyanyihao oral solution were quickly absorbed, and their peak concentration occurred at less than 0.5 h. The pharmacokinetic parameter of the average t1/2 from Danshensu was 3.91 h in rats, and it was the most rapid distribution and elimination among the components. In addition, the Cmax of stachydrine and baicalin were revealed as the higher plasma concentrations in rats. Conclusions. This pharmacokinetic study seems to be useful for a further clinical study of Shenyanyihao oral solution in the treatments of chronic nephritis.

A novel symmetric and asymmetric hybrid optical cryptosystem is proposed based on compressive sensing combined with computer generated holography. In this method there are six encryption keys, among which two decryption phase masks are different from the two random phase masks used in the encryption process. Therefore, the encryption system has the feature of both symmetric and asymmetric cryptography. On the other hand, because computer generated holography can flexibly digitalize the encrypted information and compressive sensing can significantly reduce data volume, what is more, the final encryption image is real function by phase truncation, the method favors the storage and transmission of the encryption data. The experimental results demonstrate that the proposed encryption scheme boosts the security and has high robustness against noise and occlusion attacks.

We propose and experimentally demonstrate annular arrayed-Airy beams (AAABs) carrying vortex arrays by combining multiple beams. The propagation dynamics and abrupt autofocusing property are studied. The focal intensity can be greatly increased by two orders of magnitude by increasing vortex array number. Furthermore, the autofocusing property is also enhanced significantly. This tightly autofocusing property would be advantageous for the generation of high intensity laser, optical manipulation, medical treatments, and nonlinear effects.

By handling conflicting traffic movements and establishing dynamic coordination between intersections in real-time, the Adaptive Signal Control System (ASCS) can potentially improve the operation and safety of signalized intersections on a corridor. This study identifies the hierarchical effects of ASCS on the crash severity by exploring the heterogeneous effect of ASCS on the crash severity. Four different random-parameter ordered regression models (two ordered probit models, and two ordered logit models) are developed and compared. The analysis reveals that the random-parameter ordered probit and logit models (ROP and ROL) with observed heterogeneity perform better than the random-parameter ordered probit and logit models (RP and RL) without observed heterogeneity in terms of the Akaike information criteria and the goodness of fit of the model. The ROP model performs better than the ROL model in terms of classification model performance measures. The ROP model enables parameters (i.e., the coefficients of the explanatory variables) to vary as a function of explanatory variables as well as across observations, thus accounting for both observed (captured by available explanatory variables) and unobserved (not captured by available explanatory variables) heterogeneity. The analysis reveals that the presence of ASCS is associated with lower crash severity. In this study, observed heterogeneity of ASCS effects on the crash severity is captured by variables related to the intersection and corridor features. Other contributing factors besides ASCS, such as annual average daily traffic, speed limit, lighting, peak period, crash type (rear-end, angle), and pedestrian involvements, are also associated with the probability of crash severity. Unobserved heterogeneity of the effect of angle crash type on the crash severity is found to exist across the observations. The findings of this research have practical implications for establishing ASCS implementation guidelines in lowering the probability of higher crash severity.

By handling conflicting traffic movements and establishing dynamic coordination between intersections in real-time, the Adaptive Signal Control System (ASCS) can potentially improve the operation and safety of signalized intersections on a corridor. This study identifies the hierarchical effects of ASCS on the crash severity by exploring the heterogeneous effect of ASCS on the crash severity. Four different random-parameter ordered regression models (two ordered probit models, and two ordered logit models) are developed and compared. The analysis reveals that the random-parameter ordered probit and logit models (ROP and ROL) with observed heterogeneity perform better than the random-parameter ordered probit and logit models (RP and RL) without observed heterogeneity in terms of the Akaike information criteria and the goodness of fit of the model. The ROP model performs better than the ROL model in terms of classification model performance measures. The ROP model enables parameters (i.e., the coefficients of the explanatory variables) to vary as a function of explanatory variables as well as across observations, thus accounting for both observed (captured by available explanatory variables) and unobserved (not captured by available explanatory variables) heterogeneity. The analysis reveals that the presence of ASCS is associated with lower crash severity. In this study, observed heterogeneity of ASCS effects on the crash severity is captured by variables related to the intersection and corridor features. Other contributing factors besides ASCS, such as annual average daily traffic, speed limit, lighting, peak period, crash type (rear-end, angle), and pedestrian involvements, are also associated with the probability of crash severity. Unobserved heterogeneity of the effect of angle crash type on the crash severity is found to exist across the observations. The findings of this research have practical implications for establishing ASCS implementation guidelines in lowering the probability of higher crash severity.

White light diffraction phase microscopy (wDPM) combines many of the best attributes of current quantitative phase imaging (QPI) techniques, which fully takes advantages of both high temporal and spatial phase sensitivity granted by the common-path geometry and the white light illumination. However, like all off-axis quantitative phase imaging methods, although wDPM benefits from the acquisition rate due to the single shot measurement, it is characterized by a reduced space–bandwidth product, compared to phase shifting approaches. In the paper, we develop slightly off-axis blind two-step phase-shifting wDPM, measuring two phase-shifted interferograms by blindly shifting the grating. Due to the combination of phase-shifting and off-axis techniques, the time–bandwidth and space–bandwidth products are well traded off. In addition, the phase-shifting is simply implemented by blindly shifting the grating with a stepping motor linear translation stage, not requiring a precise phase modulator. Thus, the apparatus is cost-effective and offers ease of alignment. Some experimental results are given to demonstrate the feasibility of the method.

Objectives. To investigate the mechanism of the protective effect of Zishenwan on pyelonephritis rats. Methods. In the rat model of pyelonephritis, protective effects of Zishenwan, the content of secretory immunoglobulin A (SIg A), and interleukins were detected by ELISA. The expressions of TLR4-NFκB pathway were detected by Western blot in renal and urinary tract mucosa. The protective effect and influence on TLR4-NFκB pathway of Zishenwan were studied. Results. Zishenwan protected rats from pyelonephritis which related to the increase of SIgA, the regulation of interleukins, and the inhibition of TLR4-NFκB pathway. Serum containing Zishenwan can significantly decrease LPS-induced expression of TLR4, MyD88, and NFκB in vitro. And the inhibition of TLR4 signal by Zishenwan related to the degradation of TRAF3 and TRAF6. Conclusions. Zishenwan protected rats from urinary tract infection by clearance of bacteria and decrease of tissue damage. 20S proteasomes mediated the degradation of TRAF3 which is important to the decrease of tissue damage from Zishenwan.

Helicobacter pylori-induced inflammation significantly increases the risk of gastric cancer. To investigate the role of H. pylori infection in gastric epithelial cell carcinogenesis, flow cytometry was used to analyze the apoptosis of gastric epithelial cells infected by H. pylori. Next, LTQ MS mass spectrometry (MS) was applied to identify protein changes in gastric epithelial cells infected with H. pylori, and then bioinformatics was adopted to analyze the cellular localization and biological function of differential proteins. LTQ MS/MS successfully identified identified 22 differential proteins successfully, including 20 host-cell proteins and two H. pylori bacterial proteins. Also, human proteins were located in all areas of cells and involved in various cell biological functions. The oncogene proteins p53, p16, and C-erbB-2 proteins in H. pylori-infected RGM-1 cells were remarkably increased from the analysis by Western blot analysis. H. pylori infection of gastric epithelial cells leads to changes in various protein components in the cell, and enhances the expression of oncogene proteins, thereby increasing the possibility of possibility of carcinogenesis of H. pylori infection.

An optical encryption of three-dimensional (3D) object with digital holography was implemented. In the process of encryption, two holograms involved recording key information and 3D object were obtained. In the process of decryption, the 3D object was reconstructed from the two holograms by extracting the object and key information, followed by multiplication of the two holograms and inverse Fresnel transform numerically. The robustness of the method was also tested for different occlusions attacks and Gaussian noises. The results showed that the method was able to encrypt and decrypt the 3D object while being robust under different occlusions attacks and Gaussian noises.

A novel technique of optical color image encryption and decryption based on computer generated hologram (CGH) and chaotic theory is proposed. The tri-color separated images of an image to be encrypted are encoded with three random phase arrays constructed by a chaotic sequence of the deterministic non-linear system, respectively. Then Burch's encoding method using the modified off-axis reference beam is adopted to fabricate the CGH as the encryption image. A clear original color image can be reconstructed as long as the correct initial value of chaotic sequence and the correct system parameters are given. The initial value of chaotic function with a very small change will lead to the generation of an entirely different chaotic sequences. As a result, the random phase array changes dramatically and the original image cannot be recovered rightly. Serving as the secret keys, the initial values of chaotic sequence and system parameters reduce the amount of the key data. And the digital encryption image is also more favorable to be stored and transmitted. The feasibility and its robustness against occlusion and noise attacks are verified by numerical simulations.

MicroRNA-135a (miR-135a) is implicated in the pathological processes of several cancers. However, the roles and regulatory mechanism of miR-135a in sepsis-induced myocardial depression (MD) remain largely unknown. In this study, the serum of patients with sepsis and healthy controls was obtained. The miR-135a expression was then measured. Then lentiviruses (miR-135a mimic, inhibitor and scramble control) were transfected into BALB/c mice. After 4days of transfection, polymicrobial sepsis model was established by cecal ligation and puncture (CLP) surgery. The serum tumor-necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and IL-6 were detected. Cardiac function was assessed. In addition, the protein expressions of p38 MAPK/NF-κB pathway-related proteins were determined. Besides, SB203580 and JSH-23, the inhibitors of p38 MAPK and NF-κB respectively, were used to treat the isolated ventricular myocytes in vitro. MiR-135a was significantly up-regulated in the serum of patients with sepsis. In comparison with CLP group, the concentrations of TNF-α, IL-1β and IL-6 and the expressions of p-p38 and p-p65 in CLP+miR-135a mimic group were significantly increased, while markedly decreased in CLP+miR-135a inhibitor group. Moreover, EF, FS, LVdP/dt (max), LVdP/dt (min) and LVDP of CLP+miR-135a mimic group were all significantly decreased, while markedly increased in CLP+miR-135a inhibitor group. Besides, the increased expressions of p-p38 and p-p65, decreased expression of p-IKBα and the decreased percentage of contraction amplitude in miR-135a mimic group were markedly reversed by SB203580 or JSH-23 treatments. Up-regulation of miR-135a could aggravate sepsis-induced inflammation and myocardial dysfunction via activation of p38 MAPK/NF-κB pathway.

A novel optical image encryption is proposed based on two-step-only quadrature phase-shifting interferometry.Only two interferograms are needed to reconstruct a zero-order-and twin-image-free hologram in this phase-shifting digital holography interference.Such technique precludes the need from recording either the reference wave or the object wave intensity.The object wavefront propagates with two Fresnel transforms in the light path,combined with the double random phase encoding.The following is that introducing zero and л/2 phase into reference waves respectively and recording two digital holograms as encrypted image.As long as the correct key is given in the decryption,a clear original image can be reconstructed by a simple calculation.The feasibility and its robustness against occlusion and noise attacks are verified by a series of numerical simulations.

The optical image encryption based on multichannel fractional Fourier transform (FRT) and double random phase encoding technique is proposed. Optical principles of encoding and decoding are analyzed in detail. With this method, one can encrypt different parts of input image, respectively. The system security can be improved to some extent, not only because fractional orders and random phase masks in every channel can be set with freedom, but also because the system parameters among all channels are independent. Numerical simulation results of optical image encryption based on four channel FRT and double random phase encoding are given to verify the feasibility of the method.

Buses often have strong bunching or large interval tendency when traveling further along the route. To restrain this further deterioration of operation service, this paper developed a bus operation control system to dynamically adjust bus speed, bus dwell time, and traffic signal timings along the running path. In addition, a simulation platform was developed to evaluate the proposed control system with the actual data collected from bus route number 210 in Shanghai. The simulation results show that the proposed control system can mitigate the amplification trend of the headway deviation along the route to produce headways within a given tolerance.

Based on the conventional correlation and fractional correlation, the extended fractional correlation (EFC) is presented. And based on the configuration of the nonconventional joint transform correlator, we propose the joint extended fractional Fourier transform correlator (JEFRTC). The properties of the extended fractional cross correlation peak (EFCCP) in theory are analyzed. A sound conclusion is drawn that the width of EFCCP is narrower than that of fractional correlation peak under some conditions. This JEFRTC can permit lower precision of the systemic parameters when implemented with optical configuration. That will improve correlator’s character discriminability.

Real color fractional Fourier transform holography is proposed based on fractional Fourier transform holography. The method of fabrication, the principle of reconstruction and the design of system parameters are discussed in detail. The experiments prove real color fractional Fourier transform holograms possess the better function of anti-counterfeit than common fractional Fourier transform holograms.

We consider the behaviour of buckling-driven thin-film blisterings using Von Karman's plate theory. Our results are asymptotic in the thinness and emphasize the incorporation of in-plane displacements in the model, a factor often ignored in the literature. Our work indicates that the inclusion of these displacements has a profound effect on the nature of solutions. We compare different constraints on displacements by estimating the leading order of corresponding energies. Our results strongly suggest that branching and other fine-scale structures arise in thin-film blistering, as has been observed in experiments.

We consider the behavior of buckling driven thin-film blisterings using von Karman’s plate theory. Our focus is on the setting where the blistered region is the unit square with clamped boundary conditions at the vertical sides and periodic ones along the horizontal sides. In this setting, we prove rigorous upper and lower bounds for the elastic energy which are of the same order as the film thickness. We also present a convincing argument for the necessity of branching of folds near the boundary as has been observed in experiments.

in two space dimensions. We introduce a new scheme for proving lower bounds and show the bounds are asymptotically sharp for certain domains and boundary conditions. Our results support the conjecture, due to Aviles and Giga, that folds are one-dimensional, i.e., \nabla u varies mainly in the direction transverse to the fold. We also consider related problems obtained when (1-|\nabla u|2)2 is replaced by (1-δ2 ux2 - uy2)2 or (1-|\nabla u|2)2γ .

Bus running state is always influenced by traffic flow. Traffic flow state evolution directly leads to the variation of bus speed, thereby affecting bus progress. Some investigations implied that there is a certain relationship between the bus speed and other traffic vehicle speed on the road. However, the relationship is different due to individual forms of road cross-sections, the number of lanes, and the traffic flow characteristics. Based on this mechanism and the forecast of road traffic flow data provided by intelligent transportation system (ITS), a state recognition-based model for travel time prediction is proposed, and three running states are introduced in the model. Finally, the bus travel time predicted by the proposed model are assessed with real-world data collected from bus route number 53 in Wuxi city. Results show that the proposed model outperforms the history data-based model, especially when the bus running state falls unstable; the model achieves satisfactory performance.

An efficient approach is presented to restore a motion-blurred image in real time by optoelectronic hybrid processing, by which an image motion vector can be effectively detected and an accurate point spread function is constructed rapidly. A simple Wiener filter algorithm is employed to restore the blurred image. It greatly alleviates the complexity of the restoration algorithm. The proposed approach can apply to arbitrary motion-blurred image restoration. An optoelectronic hybrid joint transform correlation is constructed to verify the efficiency. The experimental results show that the proposed method has distinct advantages of preferable effect and good real time.

A method combining the principal component analysis (PCA) and the least squares method (LSM) is proposed to extract the phase from interferograms with random phase shifts. The method estimates the initial phase by PCA, and then determines the correct global phase sign and reduces the residual phase error by LSM. Some factors that may influence the performance of the proposed method are analyzed and discussed, such as the number of frames used, the number of fringes in interferogram and the amplitude of random phase shifts. Numerical simulations and optical experiments are implemented to verify the effectiveness of this method. The proposed method is suitable for randomly phase-shifted interferograms.

Shear behavior is an interesting subject of soft soil engineering, and it is important to determine shear critical state under complex stress conditions. In this paper, eight failure criteria are established according to Mohr stress cycle and Coulomb strength theory. Three criteria are based on conventional soil mechanics, and the other three criteria are based on geometry-algebra theory. Last two criteria are on the basis of interdiscipline involving soil mechanics and geometry-algebra theory. Finally, example is introduced to verify correctness of these criteria and good agreements have been found.

A novel single-channel color image encryption technique based on joint fractional Fourier transform correlator(JFRTC) and phase retrieval algorithm (PRA) is proposed. The target color image is decomposed into three red, green, blue (RGB) components. A joint image is formed and encoded into two random phase masks (RPM) iteratively. The security of the system is enhanced because of the fractional order as a new added key. The system and the operation procedure are simplified. Simulation experiments show that the algorithm converges rapidly and has great design flexibility. The decryption can be realized by digital or optical methods.

The effects of fast ( E n =14 MeV ) and thermal ( E n =0.025 eV ) neutron irradiation on quantum transport in modulation-doped heterostructures and double barrier resonant tunneling diodes have been investigated. In the case of modulation doped heterostructures, both concentration and mobility of the 2DEG at 4.2 K decreased in the dark after fast neutron irradiation. The Hall plateau broadened and the SdH oscillation was clearly enhanced under high magnetic fields. The increase of the concentration and mobility of 2DEG, Hall plateau broadening and SdH oscillation enhancing as well as parallel conductance were observed at 4.2 K in samples irradiated by thermal neutrons. All changes disappeared gradually with time. In double barrier resonant tunneling structures irradiated by fast neutrons, the peak current position V p , valley current I p and peak-to-valley ratio (PTVR) decreased.

In this paper, a new system of multi-channel single-output rotation-invariant joint fractional Fourier transform correlator (JFRTC) for color pattern recognition is proposed. Due to the shift-variant property of fractional Fourier transform (FRT), we can obtain three correlation peaks at the output plane which show a pair of cross-correlation peaks that is desired and one autocorrelation peak, so the noise is greatly reduced. The Synthetic discriminate function (SDF) is quoted at the input plane to store the reference images to realize rotation-invariant recognition. To optimize the correlation peaks, the joint power spectrum is binarized to perform Fourier transform. The theoretical analysis and optical experiments are discussed in detail. Experimental results are presented to demonstrate the ability of this system.

A fundamental problem in optical and digital holography is the existence of speckle noise in the reconstructed image. Many approaches have been carried out in order to overcome this problem. In this paper a new technique to reduce the speckle noise is proposed based on the physical nature of speckle noise. The illumination direction of the object beam is changed to provide a different phase information for the same recorded object in an off-axis digital holographic setup and the holograms are recorded with different illumination directions. Then the intensity information of the reconstructed images is superposed and averaged to reduce the speckle noise. The theoretical analysis and experimental results are shown to valid our proposal. They prove that the technique can effectively reduce the speckle noise without ruining the object information.

Based on the extended fractional Fourier transform, we propose a zone-processing joint extended fractional Fourier transform correlator. With the zone-processing technique, first, the high- and low-frequency zone can be obtained from high- and low-brightness joint extended fractional Fourier transform power spectra, respectively. Second, they are combined into new power spectra, so it can preferably include high- and low-frequency information simultaneously. The experiment results demonstrate that this processing technique can largely improve correlation performance.

We present an efficient approach to restoring a blurred image in real time by using opto-electronic hybrid processing, by which an image motion vector can be effectively detected and an accurate point spread function (PSF) was modeled rapidly. A Wiener filter was adopted to restore the blurred image, greatly simplifying the complexity of the image restoration algorithm. The approach applies to the restoration of arbitrary motion blurred images. An opto-electronic hybrid joint transform correlation (JTC) was constructed to confirm the efficiency. The experimental results show that the proposed method has the distinct advantages of real time and good effect.

In this paper, an optical color image encryption/decryption technology based on joint fractional Fourier transform correlator and double random phase encoding (DRPE) is developed. In this method, the joint fractional power spectrum of the image to be encrypted and the key codes is recorded as the encrypted data. Different from the case with classical DRPE, the same key code was used both in the encryption and decryption. The security of the system is enhanced because of the fractional order as a new added key. This method takes full advantage of the parallel processing features of the optical system, and could optically realize single-channel color image encryption. The experimental results indicate that the new method is feasible.