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This paper presents a simplified procedure for predicting the seismic slip of a vegetated slope. This is important for more precise estimation of the hazard associated with seismic landslip of naturally vegetated slopes, and also as a design tool for determining performance improvement when planting is to be used as a protective measure. The analysis procedure consists of two main components. Firstly, Discontinuity Layout Optimisation (DLO) analysis is used to determine the critical seismic slope failure mechanism and estimate the corresponding yield acceleration of a given slope. In DLO analysis, a modified rigid perfectly plastic (Mohr–Coulomb) model is employed to approximate small permanent deformations which may accrue in non-associative materials when subjected to ground motions with relatively low peak ground acceleration. The contribution of the vegetation to enhancing the yield acceleration is obtained via subtraction of the fallow slope yield acceleration. The second stage of the analysis incorporates the vegetation contribution to the slope's yield acceleration from DLO into modified limit equilibrium equations to further account for the geometric hardening of the slope under increasing soil movement. Thereby, the method can predict the permanent settlement at the crest of the slope via a slip-dependent Newmark sliding block approach. This procedure is validated against a series of centrifuge tests to be highly effective for both fallow and vegetated slopes and is subsequently used to provide further insights into the stabilising mechanisms controlling the seismic behaviour of vegetated slopes.

Many natural and man-made slopes are planted with vegetation, and it is known that this can increase the stability of slopes under static conditions. There is anecdotal evidence that vegetated slopes also perform better than fallow slopes during earthquakes. However, the study of the dynamic behaviour of slopes planted with species having dichotomous (‘woody’) roots is relatively rare owing to the extreme expense and difficulty involved in conducting full-scale dynamic testing on shrubs and trees. In this paper, dynamic centrifuge testing and supporting numerical modelling have been conducted to study this problem. In the centrifuge modelling, ABS plastic rods are used to simulate repeatably the mechanical properties of real roots. The numerical modelling work consisted of two parts. First, a computationally-efficient beam-on-non-linear-Winkler-foundation (BNWF) model using existing p–y formulations from piling engineering was employed to produce a macro-element describing the individual root and soil interaction both pre- and post-failure. By adding contributions from the different root analogues of different diameters, smeared continuum properties were derived that could be included in a fully dynamic, plane-strain continuum, finite-element model in a straightforward way. The BNWF approach was validated against large direct shear tests having stress conditions simulating those in the centrifuge at different potential slip plane depths. The conversion to smeared properties for global time-history analysis of the slope was validated by comparing the continuum finite-element results with the centrifuge test data in terms of both the dynamic response and permanent deformations at the crest, and these demonstrated good agreement. Owing to the simplicity of the BNWF approach and its ability to consider variable root geometries and properties, along with variation of soil properties with depth, it is suggested that the validated approach described will be useful in linking individual root–soil interaction characteristics (root strength and stiffness, diameter variation, root spacing and so on) to global slope behaviour.

This paper reviews the study of wind induced vibration of transmission power tower-line system. Each fields of research of transmission power tower-line system —analysis model, dynamic characteristic, wind response and vibration control —are systematically introduced. the problem that exist in this stage and the development trend are summarized in the conclusions.

The impacts of wind disturbance on voltage regulation and frequency regulation of power system were studied. The opinion that the regulation of power flow on the tie lines between the grids constrains the integrated capacity of wind power was put forward. Based on the real condition of Inner Mongolia power grid, an engineering practical method was put forward to calculate the integrated capacity of wind power under this constraint. The relationship between wind power and spinning reserve and the impacts of other related factors on the capacity of wind power were studied as well. The impact of wind disturbance on voltage stability where the wind farms are located was studied.

In order to meet the need of production and promote the smelting efficiency of converter, Pangang Vanadium-extracting&Steel Making Plant optimized oxygen lance nozzle according to the situation of primary 120t converter semi-steel making and have inspected new oxygen lances smelting effect in industrial test. The test shows that the average oxygen blowing intensity raised 0.19m3/t·min with optimized nozzle, shortened oxygen blowing time by 56s,total iron in final slag reduced 0.7%, dephosphorizing rate rose to 82.10% from 79.06%, which developed a good result.

The paper introduced the process of slag-forming by using corundum slag in converter. The results showed that Al2O3 in corundum can reduce converter slag melting point, in advance of slag melting. Using this material, slagging process can be ahead of schedule for 30~40 seconds and the whole process of slag melting is good, without splashing, getting drying and lance-sticking. The consumption of metallic material and lime is reduced, and it shortens the melting period.

In order to promote the fusion of lime in semi-steelmaking, fluorite was used in converter steelmaking to improve the melting slag ratio, while fluorite is very harmful. In order to make best use of the metallurgical slag and improve the scorification problems in semi-steelmaking, PANGGANG Research Institute developed a new type high alumina composite slag, and accomplished industrial application which also achieved good results. They found that this new type slag can improve the melting slag ratio greatly and decrease the times of “re-drying” and “slopping” throughout the converter steelmaking, the slag sate can be good controlled, at the same time the content radio of TFe decreased significantly.

Steelmaking Plant of PZH Steel improves the hitting ratio of independent converter model, by optimizing the terminal controlling model of molten steel, stabilizing the charging load in BOF, accelerating the turnover rapid of ladle, improving the quality of semi-steel into the furnace and optimizing the management of production organization. So the ratio of the direct-tapping is improved and increases to more than 50% now from 25% on average in 2011.

Focus on such problems as low supplying capacity, short furnace life and poor smelting effect during extracting vanadium using combined blowing converter, the structure optimization of bottom blowing brick used to ventilating was studied, the system used to supplying gas was implemented, and the crafts of extracting vanadium with combined blowing technology was developed as well as the protecting technology of brick used to ventilating was applied. The results show that strength of gas supplying of BOF is increased to at least 0.10m3/ (min•t). The combined blowing lifetime is extended, especially reaches to 7455 heats. The proportion of multiple blowing is reached to 100%. The quality o f vanadium slag is improving obviously.

This study investigated the classification error rate of eleven flaws commonly occurred in copper foil. The goal was to online identify the type of the flaw being discovered in order to trace the source of the flaw and act correspondingly. The misclassification rates of four popular classifiers were investigated and compared. The results indicated that the best classification rate can be obtained by choosing Support Vector Machines as the classifier and employing all the ten features. The resulting low classification error rate of 4.41% proved the effectiveness of the derived classifier as well as the suitability of the chosen features.

In this study, double-slag method is used to melt low-phosphorous steel by semi-steel. The results show that, the average phosphorous content of the aimed molten iron of BOF is 0.0052% and after the first slag pure-out, the dephosphorization rate is 56.2%, while the total dephosphorization rate of BOF melting is 92.46%, rang from 91% to 93.4%. Low phosphorous content alloy and slag-stopping tapping technology is adopted and rephosphorization of molten iron is controlled in 0.002%. Finally the average phosphorous of the finished product is 0.0064%, range form 0.0055% to 0.0071%, which means that Pangang Group can produce the steel with phosphorous content is less than 0.008%.

Anthracite carburant is adopted to increase the carbon during the steel tapping of the converter of Panggang, however, it is found that the smelting time is long and the yield rate of the carbon is low which severely affect the precision control of the heat composition, so the new type of carbon-manganese alloy carburant is developed and the application effect to the industry is investigated. The results show that this new type carbon-manganese alloy carburant smelting much faster, and the yield of the carbon and manganese are high, the average yield of carbon is 92.95%, which is 7.36% higher than anthracite, the manganese is 93.31%。This new type carburant for increasing the carbon can decrease the temperature of the tapping in the promise of keeping the quality of liquid steel, shorten the logistic time and reduce the cost of steel per ton.

The objective of this study is to measure flank wear of dry milling 6061 aluminum alloy of different PVD (Physical Vapour Deposition) multilayer coatings (including TiN, TiCN, and TiAlN) single edge rhombus micro-end-milling tools. All of the experiments were designed using the Taguchi method in order to obtain robust results. In order to realize the level of importance of each machining parameter, the L9(34) orthogonal array, analysis of variance (ANOVA), and signal-to-noise (S/N) ratio were determined. The tool wear images are captured using a machine vision system incorporated with an effective corner detection algorithm. During the milling test, we fixed spindle speed at 6000 rpm and feed rate at 0.0125 mm/rev to investigate the correlation between side clearance angle and coating materials. The experimental results show that TiCN-coating mills generate minimum flank wear and longest tool life.

In order to solve the problem of long melting time and low yield rate of carbon while blind coal is used to recarburize, a new carburant is developed to replace blind coal. Experiment results show that compared with the blind coal, the new carbon-manganese alloy carburant obtains a high smelting velocity, and the average carbon yield rate is 92.95%, which increase by 7.67%, the yield rate of manganese is 93.31%, which a little higher than other normal manganese alloys. After carbon-manganese alloy is used to recarburize, logistics time and power consumption are saved and the cost of steel-making is reduced by 1.05 ¥/t. In addition, there is little effect on the quality of steel.

According to the structure of purging plugs, the limit gas flow is obtained through theoretical calculation or practical test, that the minimum gas flow is 45Nm3/h and the maximum gas flow is 200Nm3/h.Different bottom blowing patterns suitable for smelting system were established based on different gas supply conditions about two and four purging plugs, at the same time, the maintenance technology of purging plug is developed under the condition of semi-steel steelmaking, these technologies are technology that is effective to improve the service life of purging plugs. A good result has been obtained after the combined blowing technology was put into production. The life of combined blown converters were greatly improved, the average life of combined blown is over 7000 heats, the life of combined blown can be the same with that of converter, the TFe in the slag is lowered by 3.25%, the [O] in steel is decreased by103PPm, the measured [C]·[O] at the end point of smelting is as high as 0.0026, the yield of alloy is increased significantly.

PurposeThe detection of invisible micro cracks (μ‐cracks) in multi‐crystalline silicon (mc‐si) solar wafers is difficult because of the wafers' heterogeneously textured backgrounds. The difficulty is twofold. First, invisible μ‐cracks must be visualized to imaging devices. Second, an image processing sequence capable of extracting μ‐cracks from the captured images must be developed. The purpose of this paper is to reveal invisible μ‐cracks that lie beneath the surface of mc‐si solar wafers.Design/methodology/approachTo solve the problems, the authors first set up a near infrared (NIR) imaging system to capture images of interior μ‐cracks. After being able to see the invisible μ‐cracks, a region‐growing flaw detection algorithm was then developed to extract μ‐cracks from the captured images.FindingsThe experimental results showed that the proposed μ‐cracks inspection system is effective in detecting μ‐cracks. In addition, the system can also be used for the inspection of silicon solar wafers for stain, pinhole, inclusion and macro cracks. The overall accuracy of the defect detection system is 99.85 percent.Research limitations/implicationsAt present, the developed prototype system can detect μ‐crack down to 13.4 μm. The inspection resolution is high but the speed is low. However, the limitation on inspection speed can easily be lifted by choosing a higher resolution NIR camera.Practical implicationsGenerally, this paper is a great reference for researchers who are interested in developing automatic optical inspection systems for inspecting solar wafer for invisible μ‐cracks.Originality/valueThe research described in this paper makes a step toward developing an effective while low‐cost approach for revealing invisible μ‐crack of mc‐si solar wafers. The advantages provided by the proposed system include excellent crack detection sensitivity, capability of detecting hidden subsurface μ‐cracks, and low cost.

According to the actual characteristics of semi-steel steelmaking of PZH steel, a static model for prediction of the oxygen blow amount and consumption of auxiliary material is established, and an end-point prediction model based on carbon content and temperature of sublance is given. This paper introduced the calculating principle and basic structure about above two models detailed. The results show that, the static model has certain accuracy and reliability of these models are illustrated by actual application.The static model might provide immediately the predicting optimum auxiliary material amount and the oxygen blow amount for operator, which direct the operation in time. The end-point prediction model might give real time prediction for the carbon content and temperature on BOF Endpoint, which has high hitting ratio.

This paper applied Grey-Taguchi method to optimize the micro-drilling of PMMA polymer with multiple performance characteristics. The four parameters being optimized are coating layer, feed rate, spindle speed, and depth of cut. The performance of the drilling process was evaluated by two performance characteristics, namely drill wear and surface roughness. The orthogonal array, grey relational analysis, and analysis of variance were used to study the two performance indices. The optimal combination of parameters was determined by using the grey relational grade, a performance index formed by combining the two performance characteristics. The experimental results show that TiAlN-coating drills generate least wear and thus possess the longest tool life and the best holes quality. Finally, confirmation experiments were conducted to confirm the validity of the results.

This study proposes a tool wear automatic monitoring system based on multiple parameters analysis of cutting force and machine vision technique. A drilling model of cutting parameters (cutting force, coating layer, spindle speed and feed rate) and tool condition (focusing on tool flank wear measurement and analysis) was developed. The experimental design methods developed in this study can be used to optimize cutting parameters efficiently and reliably. The drilling model based on cutting parameters was constructed using Taguchi method. This method enabled evaluation of wear status based on the actual force obtained from a dynamometer. The derived relation is useful for in-process wear monitoring. Tool wear dynamics are extremely complex and not yet fully understood. Therefore, vision-based tool wear monitoring techniques can help elucidate wear progression. In this study, a drilling model based on the machine vision technique was used to establish a direct relation between cutting parameters and tool wear. The object of the experiments was to measure the flank wear of cutting tools with various coatings. The experimental results show that the monitoring system clarifies the relationships between cutting force and multiple cutting parameters.

PVD (Physical Vapour Deposition) multilayer coatings were extensively used in cutting tools because of their relatively high wear and corrosion resistance, adhesion strength, hot hardness, and low coefficient of friction. The object of this study is to measure flank wear of dry cutting drills of different PVD coatings, including TiN, TiCN, and TiAlN by using drilling force experiments and machine vision technique incorporated with image registration technique. To obtain an optimal combination of cutting parameters quickly, we applied Taguchi method to plan the drilling experiment. The experimental results show that coating layer is the most important control factor for cutting and the TiAlN-coating drills generate least wear and thus has the longest tool life.

The purpose of this paper is to monitor the tool wear based on the image data of cutting tool in the face milling operation. The surface images of the different coated inserted blade cutters are captured using a machine vision system incorporating with the mutual information and image similarity analysis technique for processing the images. The milling test is designed by using Taguchi’s method. The experimental results indicate that the coating layer factor is recognized to make the most significant contribution to the over all performance. The TiAlN-surface multilayer coated inserted blade cutter has the least wear rate amongst these coated milling cutters and has the longest tool life in this experiment.

This study proposes a tool wear monitoring system based on machine vision technique. The tool wear of single edge rhombus micro-end-mills with mill parameters (Side Clearance Angle, different coating layer, feed rate and spindle speed) in milling 6061 aluminum alloy was experimentally investigated in this study. A L 9 (34) orthogonal array, analysis of variance (ANOVA) and signal-to-noise (S/N) were determined to know the level of importance of the machining parameters. Using Taguchi method for design of a robust experiment, the interactions among factors are also investigated. The experimental results indicate that Side Clearance Angle and coating layer are recognized to make the most significant contribution to the overall performance. The correlation was obtained by multi-variable nonlinear regression and compared with the experimental results. The experimental results showed that Using TiCN-coated micro-end-mill and setting side clearance angle at 12 degrees, spindle speed at 6000 rpm and feed rate at 0.0125 mm/rev minimized the wear on micro-end mills and maximized tool life. The confirmation tests demonstrated a feasible and an effective method for the evaluation of tool wear in milling of 6061 aluminum alloy.

The vision-based of automated tool wear monitoring systems are very important and efficient for unmanned machining systems. This research is use the machine vision inspection technique to automatic tool wear monitoring measurement of different coated drills. The tool wear images are captured using a machine vision system incorporating with an effective extract vertex algorithm based on subpixel edge detector and Gaussian filter is presented. Finally, Statically Process Control (SPC) technique is applied to detect vertices. The results show that the proposed algorithm is an effective method for the different coated drilling factor is recognized to make the most significant contribution to the over all performance. The TiAlN-coated drilling has the least wear rate amongst these coated drilling cutters and has the longest tool life in this experiment.