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Early euarthropod evolution involved a major transition from lobopodian-like taxa to organisms featuring a segmented, well-sclerotized trunk (arthrodization) and limbs (arthropodization). However, the precise origin of a completely arthrodized trunk and arthropodized ventral biramous appendages remain controversial, as well as the early onset of anterior‒posterior limb differentiation in stem-group euarthropods. New fossil material and micro-computed tomography inform the detailed morphology of the arthropodized biramous appendages in the carapace-bearing euarthropod Isoxys curvirostratus from the early Cambrian Chengjiang biota. In addition to well-developed grasping frontal appendages, I. curvirostratus possesses two batches of morphologically and functionally distinct biramous limbs. The first batch consists of four pairs of short cephalic appendages with robust endites with a feeding function, whereas the second batch has more elongate trunk appendages for locomotion. Critically, our new material shows that the trunk of I. curvirostratus was not arthrodized. The results of our phylogenetic analyses recover isoxyids as some of the earliest branching sclerotized euarthropods, and strengthens the hypothesis that arthropodized biramous appendages evolved before full body arthrodization.

Objective To explore the effect of massage based on midnight-noon ebb-flow theory on milk secretion primiparas. Methods A total of 70 primiparas were selected and divided into the control group and the study group, with 35 cases in each. Both groups were given breastfeeding for the first time within 2 hours, the control group was given regular massage, and the study group was given massage based on midnight-noon ebb-flow theory. The milk production, prolactin level, breast tenderness rating and breastfeeding rate were compared between the two groups. Results After 5 days of intervention, the levels of prolactin and milk production in the two groups increased compared with 24 hours postpartum, those in the study group were more than those in the control group, and the differences were statistically significant (P

Objective To explore the effect of bright light therapy combined with five-element music therapy on negative emotions and sleep quality of pregnant women with depression. Methods Totally 70 cases of depressed pregnant women were selected and randomly divided into control group and study group, with 35 cases each. Patients in the two groups were given routine nursing programs, and the study group was given bright light therapy combined with five-element music therapy. The Self-rating Anxiety Scale(SAS) score, Self-rating Depression Scale (SDS) score, Pittsburgh Sleep Quality Index (PSQI) score and nursing quality indexes were compared between two groups. Results After intervention, except for the SDS score of the control group, the SAS, SDS and PSQI scores of the two groups were lower than before, and the differences were statistically significant (P

Realization of practical terahertz wireless communications still faces many challenges. The receiver with high sensitivity is important for THz wireless communications. Here we demonstrate a terahertz receiver based on the cesium Rydberg atoms in a room-temperature vapor cell. The minimum detectable THz electric field is calibrated. With this receiver, the phase-sensitive conversion of amplitude-modulated or frequency-modulated terahertz waves into optical signals is performed. The results show that the atomic receiver has many advantages due to its quantum properties. Especially, the long distance THz wireless communications is achievable using this receiver. Furthermore, the atomic receiver can be used in the THz wireless-to-optical link.

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Background Abscisic acid (ABA) acts as a signaling hormone in plants against abiotic stress, but its function in energy homeostasis under heat stress is unclear. Results Two rice genotypes, Nipponbare (wild-type, WT) with flat leaves and its mutant high temperature susceptibility (hts) plant with semi-rolled leaves, were subjected to heat stress. We found significantly higher tissue temperature, respiration rate, and ABA and H2O2 contents in leaves as well as a lower transpiration rate and stomatal conductance in hts than WT plants. Additionally, increased expression of HSP71.1 and HSP24.1 as well as greater increases in carbohydrate content, ATP, NAD (H), and dry matter weight, were detected in WT than hts plants under heat stress. More importantly, exogenous ABA significantly decreased heat tolerance of hts plants, but clearly enhanced heat resistance of WT plants. The increases in carbohydrates, ATP, NAD (H), and heat shock proteins in WT plants were enhanced by ABA under heat stress, whereas these increases were reduced in hts plants. Conclusion It was concluded that ABA is a negative regulator of heat tolerance in hts plants with semi-rolled leaves by modulating energy homeostasis.

Scientific instrument platforms (SIPs) suffer from a lack of opinion and suggestions on sustainable operation management, leading to widely poor operation status nowadays. It is possible to guarantee the quality and efficiency of scientific and technological innovation activities and to improve the economic and social benefits of scientific and technological resources by constructing a framework system to promote the sustainability of the operation and management for SIPs. To meet the examination and evaluation requirements of the current operation and management of SIPs in China, this paper aims to establish an evaluation framework composed of indicators and attributes running through the construction and development of the SIPs from four aspects of learning and growth, process management, customers, and finance. Based on the existing research and operation practice, and according to the knowledge and preference of 627 SIP stakeholders, factor analysis has been adopted to extract and validate the hierarchical structure containing key sustainability indicators. The results show that the attribute characteristics of sustainable operating management for SIPs involve four significant dimensions of target positioning, team building, internal process control, and external service, among which the first and third ones have relatively higher priority. An effective and reliable evaluation tool is identified to be designed and provided for SIP operating management, which can also be used for self-evaluation and unified management of the sustainable operation of SIPs.

Edge detection is one of the most central branches in the field of image processing. The traditional edge detection algorithm is studied for its poor resistance to pretzel noise and poor adaptability of threshold selection. An improved image edge detection algorithm based on Canny is proposed, which firstly combines improved adaptive median filtering to reduce image noise. Then, the local adaptive thresholds are used to detect the edges of the image. The comparison of experimental results shows that the improved algorithm, which addresses the shortcomings of the traditional Canny algorithm, is better at removing the interference of pepper noise and preserving the image edge details.

Supplemental material, sj-pdf-1-pic-10.1177_09544062211026352 for Contact characteristics of steel-rubber rollers based on modified contact theory considering viscoelasticity by Hongyan Chu, Qiang Yu, Caixia Zhang, Qi Chen, Ruilong Ding and Yingjie Hong in Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science

Supplemental material, sj-pdf-1-pic-10.1177_09544062211026352 for Contact characteristics of steel-rubber rollers based on modified contact theory considering viscoelasticity by Hongyan Chu, Qiang Yu, Caixia Zhang, Qi Chen, Ruilong Ding and Yingjie Hong in Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science

The rapid growth of emerging technologies with artificial intelligence and big data as new representatives has brought great influence to all walks of life, as well as the education. College sports is an important part of the education system and deeply affected by the artificial intelligence. The paper will briefly summarize the current status of college physical education in China and discuss how to innovate its methods in the era of artificial intelligence.

In this paper, we report one bifacial p-type PERC solar cell with efficiency over 22% using laser doped selective emitter produced in larger-scale commercial line on 6-inch mono-crystalline wafer. On front side of the solar cell, square resistance of p-n junction was found to be closely related with laser power at certain laser scan speed and frequency. On the other side, the rear fingers with different ratios of height and width and rear silicon nitride (SiNx) layer with different thickness were optimized, and a highest rear efficiency of the bifacial solar cell was obtained. Finally, bifacial silicon solar cells with the front and rear efficiencies exceeding 22% and 15% (AM1.5, 1000 W/m2, 25 °C) were successfully achieved, respectively.

The listed companies are outstanding representatives of enterprise groups in China that have a significant influence on the national economic development and the industrial transformation. Their choices of financing behavior are not only transparent but also have a model effect. This chapter examines the refinancing behavior of Shanxi’s listed resource companies from two aspects, general and group characteristics. The study finds that the current refinancing selection of Shanxi’s listed resource companies is a combination of results of Shanxi’s resource-based economic structure, the development cycle of the coal industry, the influence of the state-owned assets management system, the policy and social governance environment, the level of the enterprises’ own development and other factors. The chapter also puts forward some policy suggestions on various factors influencing the refinancing of Shanxi’s listed resource companies.

Bridges have become an important part of urban transport, and the length and number of Chinese bridges are world leaders. In the event of an accident, it will cause significant losses. Therefore, it is especially important to prevent the health of the bridge and to repair it in advance. This paper describes the system monitoring of bridge monitoring based on situational awareness-based big data. Based on the development process of bridge monitoring, a big data bridge processing system based on situational awareness technology is proposed. The system uses the situational awareness architecture to take machine learning as the core, and the data collected by the sensor is imported into the bridge health monitoring system. The monitoring data is processed by the expert system of machine learning, and the processing suggestions are given in the human-computer interaction interface. Finally, the paper gives the problems to be solved and future prospects of bridge monitoring.

Hydrogen bonding was used to enhance the crystallinity and thus increase the phase change enthalpy of thermoplastic poly(ethylene glycol)-based polyurethane. With novel hydrogen bonding between two hard segments (NH⋯N) in N-methyldiethanolamine-extended polyurethane (NPU), the intensity of the NH⋯OC hydrogen bond between two hard segments increased, while that of the NH⋯O hydrogen bond between soft and hard segments decreased. The crystallinity and energy storage capability of NPU benefited from these and was thus enhanced. The phase change enthalpy was approximately 140 J g−1, which is very close to the highest value reported for cross-linked polyurethane. In addition, the crystallinity and crystallite perfection of NPU increased with the regular arrangement of soft segments and the microphase separation between soft and hard domains. The influence of the three different hydrogen bonds on the phase change enthalpy, crystallinity, crystallization morphology and microphase structure of the soft segment was discussed.

Ring rot disease, caused by the Botryosphaeria berengeriana f. sp. piricola pathogen, is a destructive disease for apple production. To gain further understanding about the defense mechanisms of apple branches against ring rot disease, a comparative proteomic analysis was conducted in our study. We selected two different host responses to B. berengeriana f.sp. piricola infection or challenge, and compared the different proteomes of susceptible and resistant apple branches that had or had not been inoculated with the pathogen. By using 2-DE and MALDI-TOF-TOF MS analysis, 27 differentially expressed proteins were identified in two inoculation assays. According to their function, the proteins were categorized into five classes. In total, according to these two inoculation assays, there were six differentially expressed defense-related proteins identified in the bark of susceptible and resistant hosts, including Mal d1, ASR, and SAMS, which may play key roles for the resistance mechanisms of each host against ring rot disease. We speculated that the only up-regulation of the ASR protein and the dramatic decrease of SAMS in the resistant host may be related to its better disease resistance. In addition, a total of 10 proteins exhibited opposite expression patterns in the bark of susceptible and resistant branches, and they may also be related to the different disease resistances of the two hosts. Due to the complexity of antifungal mechanisms of apple branch hosts against ring rot disease, to obtain more valuable insights about the interaction between the apple host and B. berengeriana f. sp. piricola pathogen, many further investigations will be conducted.

Traditionally the danger cylinder is intimately related to the solution stability in P3P problem. In this work, we show that the danger cylinder is also closely related to the multiple-solution phenomenon. More specifically, we show when the optical center lies on the danger cylinder, of the 3 possible P3P solutions, i.e., one double solution, and two other solutions, the optical center of the double solution still lies on the danger cylinder, but the optical centers of the other two solutions no longer lie on the danger cylinder. And when the optical center moves on the danger cylinder, accordingly the optical centers of the two other solutions of the corresponding P3P problem form a new surface, characterized by a polynomial equation of degree 12 in the optical center coordinates, called the Companion Surface of Danger Cylinder (CSDC). That means the danger cylinder always has a companion surface. For the significance of CSDC, we show that when the optical center passes through the CSDC, the number of solutions of P3P problem must change by 2. That means CSDC acts as a delimitating surface of the P3P solution space. These new findings shed some new lights on the P3P multi-solution phenomenon, an important issue in PnP study.

It is well known that the P3P problem could have 1, 2, 3 and at most 4 positive solutions under different configurations among its 3 control points and the position of the optical center. Since in any real applications, the knowledge on the exact number of possible solutions is a prerequisite for selecting the right one among all the possible solutions, the study on the phenomenon of multiple solutions in the P3P problem has been an active topic . In this work, we provide some new geometric interpretations on the multi-solution phenomenon in the P3P problem, our main results include: (1): The necessary and sufficient condition for the P3P problem to have a pair of side-sharing solutions is the two optical centers of the solutions both lie on one of the 3 vertical planes to the base plane of control points; (2): The necessary and sufficient condition for the P3P problem to have a pair of point-sharing solutions is the two optical centers of the solutions both lie on one of the 3 so-called skewed danger cylinders;(3): If the P3P problem has other solutions in addition to a pair of side-sharing ( point-sharing) solutions, these remaining solutions must be a point-sharing ( side-sharing ) pair. In a sense, the side-sharing pair and the point-sharing pair are companion pairs. In sum, our results provide some new insights into the nature of the multi-solution phenomenon in the P3P problem, in addition to their academic value, they could also be used as some theoretical guidance for practitioners in real applications to avoid occurrence of multiple solutions by properly arranging the control points.

Sensor technology has been used in water environment, which comes into being a water environment wireless sensor monitoring network. Monitoring data in the network slowly change, so we propose a geographical energy-efficient multi-hop clustering fusion routing algorithm based on multilayer perceptron (MLP-GEEMHCFR) in this paper to reduce transmittingdata and save the network energy.The algorithm is implemented by initialization phase, stabilization phase and data fusion phase. A multilayer perceptron (MLP) neuronal function model is designed in the data fusion stage using the MLP, and effect of neuron thresholds on the algorithm fusion efficiency is analyzed in detail. The simulation results show that the performance of the MLP-GEEMHCFR is better than a geographical energy-efficient multi-hop clustering routing (GEEMHCR) algorithm without fusion. The data fusion efficiency increases with the neuron threshold.But when the neuron threshold is up to 1 or more, the increasing trend becomesslowly.

Due to the influence of space equivalent representation and pattern composition, traditional principal component analysis (PCA) is faced with challenges in identifying small faults. This paper proposes a fault diagnosis method is proposed based on multi-levels principal component space based on high-dimensional feature representation. Firstly, based on the original PCA, the dimensions are expanded first and then reduced, so that the information that cannot be expressed in the original space is fully expressed. This method further divides the principal element space based on the eigenvalues, and projects the occurrence of the event and the size of the identification abnormality according to the projection to different sub-spaces. Compared with the usual fault detection methods, simulations verify that this algorithm can effectively measure the level of faults and improve the correct detection rate of minor faults.

Multivariate statistical analysis is often used in fault diagnosis. PCA is a commonly used multivariate statistical analysis method, based on the threshold method for fault diagnosis. But the PCA is the original space of the equivalent that didn't increase any amount of information, often resulting in a lot of minor failures difficult to diagnose. Deep Learning has a successful application in pattern recognition, linear representation of detail based on multi-level network. But Deep Learning is not explainable, only to give training results and there is no theoretical basis. On the basis of the original PCA, firstly expands and then reduces the dimension. The former is intend to fully express the information which cannot be expressed in original space by adding a projection, two projection,..., on the basis of original projection, and so on. And then generate a multi-level projection frame representing the space from the sample space high-dimensional feature. Experiment shows that the minor faults that cannot be detected in the original projection space can be detected under the projection frame of the new multi-level high-dimensional feature, and the detection rate of fault detection is improved.

In this paper, from the problem of the orientation of sudden pollution source which continuously release pollutants in three-dimensional space, while the orientation of the pollution source in the real environment is random and complex under the influence of the internal movement factors of the lake reservoir fluid, the problems are discussed from two aspects. Firstly, the nonlinear least squares estimation is carried out based on the pollution source diffusion model. Then, the sequential idea is combined with the sequential unscented Kalman filter, and the pollution source is precisely orientated by using the sequential unscented Kalman filter. Secondly, under the condition that the pollutant diffusion model is unknown, the diffusion model of pollutants in the unknown diffusion model is trained by ELM to solve the problem of the orientation of sudden pollution sources. The simulation results show that the ELM trains a pollutant concentration diffusion equation, which can effectively avoid the influence of internal movement, wind or other factors, and more in line with the actual environment. After training the concentration diffusion model, it is possible to reduce the complexity of numerical calculation, improve the performance of orientation and improve the robustness of orientating based on the application of the sequential unscented Kalman filter.

Owing to the complexity of sampling processes and running environment of the system, it is hard to avoid abnormal data such as outliers as well as patchy outliers, which widely emerge out of the sampling series. These abnormal data have remarkably bad impact on state estimation, process monitoring, process control as well as safe running of the dynamic system. In this paper, a detailed review is given to describe some research courses and prominent approaches and status quo of outlier-tolerant computation, such as outlier-tolerant estimation, outlier-tolerant identification, outlier-tolerant filtering, outlier-tolerant prediction, etc. At the end of this paper, three open problems are pointed out.

This paper presents a rapidly and lower neural networks to treat those waste water index that is difficult to be measured. Model called soft sensor is composited two parts: one is used to estimate the principal linear output, the other one is used to adjust estimated error to obtain better accuracy. Selection of features that effects greatly computation scale and predict accuracy is discussed also to achieve a better result. Finally, an experiment is provided for testing. Simulation results show the method proposed here is valid and has good performance.

Based on the functional process of carbon sequestration of forest, we categorize carbon sequestration in two parts: carbon capture and carbon storage. Here, Pinus sylvestris var. mongolica was used to simulate the dynamic changing process of carbon sequestration of forest in a century using tree growth formula and the cost of carbon capture and sequestration. We found that the total carbon captured and stored by 100-year-old P. sylvestris var. mongolica are both 966 kg C tree-1. On the assumption that the current year is the planting year, the present total carbon sequestration value (capital value) of 100-year-old P. sylvesrtis var. mongolica is 54.78 USD tree-1 at the discount rate of 3%, with the present total carbon capture value of 18.92 USD tree-1 and carbon storage value of 35.86 USD tree-1. The dynamic process of the annual value of carbon capture is illustrated by an upside-down U shape curve, while that of carbon storage service follows an S shape curve. The combination of the dynamic ...

In this paper, a software-defined radio access network (SD-RAN) is considered where content caching is performed at the small-cell base stations (SBSs) under the coordination of a central macro-cell base station (MBS). Two benchmark algorithms are firstly discussed to maximize the content hit ratio within the associated small cells locally and to maximize the content hit ratio within the macro cell, respectively. In order to minimize the content provisioning cost of the entire SD-RAN, it needs to strike a balance between the local hit ratio and the hit ratio within the macro cell. With this inspiration, a heuristic cooperative caching algorithm is proposed by dividing the cache space at each SBS into two portions for storing the duplicated contents and unique contents respectively. The optimal partition factor at which the average content provisioning cost of SD-RAN is minimized is analytically obtained in a closed form.

Given the existence of transaction costs, the location of property rights is an important factor in determining the incentives for efficient levels of investment at various levels of the industry. This paper applies some of the economic theories of property rights and industrial structure to the issues concerning the conservation of biodiversity. Although the expansion of Intellectual Property Rights (IPR) systems into the area of genetic resources has increased private investment in R&D process of the agriculture, it does not generate enough incentives for in situ conservation of biodiversity. To solve this economic inefficiency, farmers’ rights and other design of incentives and institutional arrangement should be reconsidered.

A power converter is a time-varying system which featured with typical characteristic of nonlinearity. Therefore, it lacks of a systematic way to investigating the controllability due to the limitations of linear circuit theory. In order to study the controllability of three-phase inverters in this paper, the three-phase three-wire inverter and the three-phase four-wire inverter are modeled as switched linear systems. Then, the state controllability of the two inverters are studied based on the controllability criterion derived from the switched system theory. Thereafter, the controllability canonical decomposition is conducted when the system is not completely state-controllable. The simulation results verified the correct of the analysis.

PTT (Precipitate-Temperature-Time) curve of X80 pipeline steel was obtained by strain relaxation method. The evolution of precipitate particle size during holding process was simulated combined with kinetic calculation, and observed using TEM in the samples of industrial produced X80 steel with different holding time. It is revealed that the shape of PPT curve is typical “C” type with the nose temperature of 900°C and incubation time of about 5s. Kinetic calculation results show that the average particle size increases obviously with the increment of holding time. Meantime, after holding for 90s at 950°C, observation of industrial produced X80 steel reveals that the proportion of precipitate particles larger than 60nm increases dramatically, which basically agreed with the calculation results. Dissolved Nb can effectively reduce grain boundary mobility and retard recrystallization by solute drag effect. Therefore, it is strongly recommended to shorten the holding time without increasing holding temperature in industrial production, so that to reduce precipitate of Nb at high temperature, and increase the strength and toughness of steel.

Effects of chemical composition and heat treatment on microstructures and mechanical properties of in-situ Mg2Si/Al-Si composites were investigated. It was found that, in the microstructure of an Al-5.7wt% Mg2Si composite with 8.2wt% extra Si, the binary eutectic Mg2Si locates at the grain boundaries with an undeveloped Chinese script-like morphology, and the primary α-Al is formed into a cell structure due to the selective modifi cation effect of the modifiers of mischmetal and Strontium salt; whereas in the composite with a near Al-Mg2Si eutectic composition and little extra Si content, the intercrescence eutectic Mg2Si formed with the binary eutectic α-Al grows into integrated Chinese scriptlike shape. As Si content increases, the eutectic Mg2Si dendrite becomes coarser in morphology but less in volume fraction. Hardness and tensile strength of the cast Mg2Si/Al-Si composites do not increase with increasing of Mg content, but they are related to the size and morphology of the eutectic and primary Mg2Si phases. Heat treatment with optimal parameters is an effective way to improve the properties of the in-situ composites.

In this paper, the problem of stabilizing two agents with a beacon into a triangular formation is studied, in which the beacon is static and the specified triangle is characterized only by interior angles constraints. Assuming that each agent can measure the bearing of the beacon in its local frame. Meanwhile, the two agents neighbor each other, that is, they communicate with each other so that they can measure the bearing angle respectively and exchange the measured angle information each other. A control strategy is proposed utilizing only angle information which steers the two agents to form a triangular formation with the beacon. Both theoretical analysis and simulations are provided to demonstrate the effectiveness of the control algorithm.

Objective: The aim of this study was to evaluate change in the sagittal position of point A due to orthodontic treatment by orthodontic community-cone beam computed tomography (CBCT). Materials and methods: 40 subjects (22 males and 18 females) who had Class II division 2 malocclusion were recruited, and 40 subjects (23 males and 17 females) who had minor crowding in the beginning of the treatment and required no or minimal maxillary anterior tooth movement were served as control. The changes in maxillary incisor inclination, sagittal position of point A, SNA angle, and movement of incisor root apex and incisal edge were calculated before and after CBCT treatment. Results: Maxillary incisors were significantly proclined in the study group but not in the control group. This proclination resulted in 2.95 mm backward movement of the root apex and 6.23 mm forward movement of the incisal edge of maxillary incisors. Point A moved 1.24 mm and 0.18 mm backward in the study and control groups, respectively. Incisor root apex and incisal edge almost remained stable in the control group. No significant change was observed in the SNA angle in both the study and control groups. However, the change in SNA between the two groups was found to be significant. Conclusions: Proclination of maxillary incisors with backward movement of incisor root apex caused posterior movement of point A. This posterior movement significantly affects the SNA angle.

In this paper, high-silicon K52 and API X52 were studied comparatively, which were with similar yield strength. The results showed that K52 with high-silicon and low-manganese asked for higher tensile strength, lower yield ratio and higher impact energy than API X52. K52 was successfully producted with more content of Nb, V, Ti and so on, which is with high tensile strength, low yield ratio and high impact energy. The oxide scale of K52 was more thichness because of the high-silic. The thickness of oxide scale could be reduced by the lower tapping temperature during hot rolling. The inclusion of silicon oxide was bad fot the toughness of welding line, which was forming during the welding process.The squeeze amount should be increased to improve the impact energy of welds.

Because of the serious non-linearity and coupling among state variables caused by the complex energy conversion process in ultrasonic motor, the motion control strategy of ultrasonic motor still need to be studied in detail to obtain better performance. As a kind of special control method, the low-frequency PWM control strategy can make the on-line optimum control easier, and may be an effective means to realize high performance motion control using ultrasonic motor. But this kind of strategy has not been studied in detail until now. This paper analyzes the difference among three low-frequency PWM control methods in details, works out the principle of selection among these methods. DOI: http://dx.doi.org/10.11591/telkomnika.v11i9.3262

This paper presents a biologically plausible model for the structural information processing in early vision. Our investigation on the frequency spectrum of natural images filtered by the retina shows that the DC component containing much redundancy information and the high frequency components containing much noisy information are reduced, while the middle and low frequency components containing much structural information are enhanced. Simple cells in the primary visual cortex (V1) extract structural primitives from the filtered signals resulting in the emergence of diverse receptive field shapes. We name these structural primitives as structors, and study the neural mechanisms responsible for this diversity of V1 simple cell receptive field shapes. Sparse coding with the L0-norm constraint is reexamined which suggests that the local structure of natural images is determined by few structors regardless of their coefficients. We perform an analysis on the spatial distribution of the input signal and prove that signals in the neighborhood of a special structor has a star shape and peaks at the structor. That is, the structors are the modes of the probability density function of the input signal, and learning the structors can be interpreted as mode detection. Mean sift method is applied to detect modes, and the updating rule for the mean shift appears to be Hebbian. We propose the Hebbian-based mean shift to simulate the emergence of the diversity of simple cell receptive field shapes. The simulation results demonstrate the robustness of the proposed algorithm in producing both Gabor-like and blob-like structors.

Alkaline solution of a rare earth (RE) and some northern mixed and heating method of rare-earth ore are used in preparation for a new type of alkaline RE coagulant. Utilize a single factor experiment and orthogonal experiment to decide the best of preparation conditions. Take the coking wastewater for example, comparision with the usual coagulant PFS and PAFC in coagulation test. Experiments show that alkaline earth coagulant coagulation is obvious better than polymerization ferrous sulfate (PFS) and polymerization ferrum aluminum coagulant (PFAC) and has high turbidity removal efficiency, fast flocs formation speed, good performance and other settlement characteristics.