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To prepare a gold plating layer with good bonding strength and weldability on the surface of Al-SiC composite materials，experiments exploring pre-treatment and surface metallization processes of materials were conducted.It was determined that using sensitization and activation directly on a clean，activated surface of substrate could achieve uniformity of heteroatomic autocatalytic center atoms on the surface of Al-SiC materials.Subsequent chemical nickel deposition was performed using a nickel sulfate system，followed by electroplating gold to form a uniform and dense gold plating layer on the substrate surface.The coating’s cross-section and surface morphology were analyzed using scanning electron microscopy (SEM).Results showed that the surface of the gold layer was uniformly colored，with uniform，continuous thickness and good bonding strength，demonstrating the feasibility and rationality of this process method.This study had significant implications for guiding subsequent gold plating production on Al-SiC materials.

The quality and physiological changes of ‘Luli’ and ‘Gala’ apples during low-temperature storage were explored to provide a theoretical basis for the storage and preservation of new mid-early ripening apple varieties. The results showed that the hardness, soluble solids content and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity of ‘Gala’ and ‘Luli’ apples showed a downward trend during cold storage and the shelf life period. After 90 days of storage, the hardness of ‘Gala’ apples decreased by 56.3%, while that of ‘Luli’ apples decreased only by 30.7%. Compared with ‘Gala’ apples, ‘Luli’ apples had lower polyphenol oxidase and lipoxygenase activities and higher contents of total phenols, flavonoids and chlorogenic acid during storage. During low temperature storage, the contents of individual phenolics in ‘Luli’ apples decreased, and the contents of chlorogenic acid, epicatechin, hypericin, and ferulic acid decreased most in the first 15 days, but did not significantly change during the shelf life period. The contents of catechins, p-coumaric acid, rutin, and caffeic acid in ‘Gala’ apples increased slightly after 15 days of low temperature storage and then decreased, but decreased gradually during the shelf life period. The contents of all phenolics decreased during the shelf life period. The major aroma components in ‘Gala’ and ‘Luli’ apples were aldehydes, alcohols and esters, among which 3-methyl-2-buten-1-ol, isoamyl benzoate, nonanal, 2-amino-6-methylbenzoic acid, 1-methyldibenzofuran and diisobutyl phthalate were only detected in ‘Luli’ apples. During low-temperature storage, the relative contents of aldehydes in both varieties decreased, while the relative contents of alcohols and esters showed an increasing trend. The relative content of alcohols in ‘Luli’ apples decreased during the shelf life period, while the opposite trend was observed for ‘Gala’ apples. In conclusion, ‘Luli’ apples exhibited higher fruit hardness, antioxidant capacity and phenol content during low-temperature storage and the shelf life period, and the overall storage quality was better than that of ‘Gala’ apples.

Mid-early maturing apples can enrich the fruit market and constitute an important part of the apple industry. It is of great significance to study the quality and storage characteristics of mid-early maturing apples. In this study, ‘Luli’ and ‘Luyan’ apples as well as their parental variety Gala (as a control) were investigated for differences in their storage quality and phenolic composition. The results showed that ‘Luli’ apples had higher soluble solid content (SSC) and skin a* value and better appearance quality compared with ‘Gala’ apples, being suitable for fresh consumption. However, ‘Luyan’ apples possessed high total acid content and low solid/acid ratio, produced a largest amount of ethylene during storage, and had poor storability. Compared with ‘Gala’ and ‘Luyan’ apples, ‘Luli’ apples had higher contents of total phenolics and flavonoids and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity, indicating stronger antioxidant capacity. The main phenolics in apples varied depending on the variety, maturity and fruit part. Chlorogenic acid was the most abundant phenolic compound in ‘Luli’ and ‘Gala’ apples, while epicatechin was the most abundant phenolic compound in ‘Luyan’ apples. The content of phenols in the peel was higher than that in the pulp. Correlation analysis and principal component analysis showed that fruit firmness had a significant negative correlation with a* value (P < 0.001), and SSC had a significant positive correlation with the contents of total phenolics, total flavonoids, chlorogenic acid and DPPH radical scavenging capacity (P < 0.001). Principal component 1 (PC1) is mainly determined by the content of total phenolics, total flavonoids, chlorogenic acid, and epicatechin. Mature ‘Luli’ and ‘Gala’ apples are relatively similar in PC1. This study provides a reference for the preservation and processing of mid-early maturing apples.

The AlCrSiN/Mo self-lubricating coating was prepared by hybrid technology of high power impulse magnetron sputtering and pulsed DC magnetron sputtering, and the structure and properties were modified by vacuum annealing. The influence of vacuum annealing temperature on composition, microstructure, mechanical and tribological properties of AlCrSiN/Mo coatings was systematically investigated by scanning electron microscope, X-ray diffractometer, electron probe analyzer, nano-indentation tester, scratch tester and friction and wear tester. The results show that all the AlCrSiN/Mo coatings possess the nanocomposite structure, namely the nc-(Al,Cr,Mo)N is surrounded by a-Si3N4 amorphous phase. After vacuum annealing, the particle size on the coating surface is increased significantly, whereas the nanohardness and critical load of the coatings are decreased correspondingly, and the wear resistance and antifriction performance are improved significantly. After being annealed at a temperature of 700 ℃, the coating presents the optimum properties with a nanohardness of 18.3 GPa, a friction coefficient of 0.51 and a wear rate of 3.4×10-4 μm3·(N·μm)-1. In this case, the characteristic values of H/E and H3/E*2 keep the highest.

[Objectives] With the rapid development of space technology, launching aircraft at sea has gradually become a future development trend. Aircraft flying in the atmosphere will sometimes encounter lightning strikes, which can cause damage to airborne equipment.[Methods] In response to this issue, two aircraft models (one with a gap and one with no gap) are built. Based on the CST transmission line matrix method, the induced electric and magnetic fields, surface current and induced current distribution of the cables of the two aircraft models are studied. At the same time, the changes in induced current in cables of different lengths are studied.[Results] For the same aircraft model, the surface electric and magnetic fields and internal electric and magnetic fields at the same axial position are not only different in induction peak value but also in change trend. The gap has little effect on the surface electric and magnetic fields of the aircraft, but the influence is particularly obvious inside the aircraft. The gap of the aircraft has a great influence on the induced current of the cable. Compared with the model with a gap, the single wire induced current peak of the model with no gap decreased by 1 000 times, and the current peak of the coaxial wire decreased by 15 times.[Conclusions] The research results of this paper can provide references for understanding the electromagnetic effect of lightning strikes on aircraft, and the results will be helpful for carrying out the next step in lightning protection work.

According to the geometric characteristics of the elliptical gear,with different eccentricity ratio of ellipse,the different transmission ratio curve is got,and then the variable speed motion of pumping unit is completed. By using the Solid Works,the 3D modeling and motion simulation of the pumping unit are completed,and by using MATLAB,the digital simulation of the elliptical gear pumping unit is completed. Comparing with the suspension point velocity and acceleration between the ordinary pumping unit and the elliptical gear pumping unit,it is finally verified that the motion performance of the pumping unit is improved by using elliptical gear to the pumping unit,which reduces the vibration impact and the energy consumption.

It introduces the common denitrification process of industrial furnace flue gas, and analyzes the problems during the operation of the selective denitrification system of the reformer in a company's hydrogen production unit. Based on the result, the process optimization scheme and countermeasures are put forward. By optimizing the structure of the feedstock line at the bottom of ammonia tank, optimizing the ammonia distribution aperture of SCR Flue gas denitration system, optimizing the fuel gas system, increasing the low-pressure steam purging pipeline, improving the quality of ammonia, increasing the ammonia concentration and a series of measures, the NOx content discharged from the device is effectively reduced, and the production and operation cost of the device is also reduced. [ABSTRACT FROM AUTHOR]

BACKGROUND: The avulsion fracture of tibial insertion of anterior cruciate ligament needs to be operated and fixed as early as possible. At present, the open reduction (absorbable screw, hollow scnew, steel wire, and titanium cable) is commonly used in the clinical treatment plan for internal fixation, which is more traumatic and has many postoperative complications. Arthroscopic reduction and elastic (suture) internal fixation of anterior cruciate ligament fracture has the advantages of minimally invasive, clear surgical field, high fixation accuracy, few complications, good fracture reduction and healing, meeting the biomechanical requirements, and allowing rapid recovery of joint function, but also has the disadvantages of insufficient strength, and osteotomy. OBJECTIVE: To compare the treatment efficacy of arthroscopic technique with Fiber Tape circular fixation and open reduction and fixation for the avulsion fracture of tibial insertion of anterior cruciate ligament. METHODS: Thirty-two patients with tibial eminence fracture at Department of Orthopedics of Shanghai China Metallurgical Hospital from January 2017 to December 2018 were enrolled. All patients signed the informed consents and the study was approved by the Ethics Committee. The patients were divided into two groups based on surgical methods: minimally invasive group (n=17, arthroscopic reduction and Fiber Tape circular fixation) and open group (n=15, open reduction and hollow tension screw fixation). The operation time, blood loss, and postoperative complications were recorded. The range of motion of knee joint, Lysholm score, and International Knee Documenting Committee score before operation, 1 and 6 months after surgery were recorded. X-ray film was used to evaluate fracture healing. RESULTS AND CONCLUSION: (1) All patients were followed up for 6-13 months. (2) There were no significant differences in age composition, fracture type, cause of injury or preoperative score between two groups. (3) X-ray film showed satisfactory fracture reduction after operation. There were no neurological, vascular injury or fracture displacement after surgery. The fractures healed well after 6 months. (4) There was no significant difference in the operation time and postoperative complications between two groups. The blood loss showed significant difference between two groups (P=0.036). (5) The range of motion of knee joint at postoperative 1 month in both groups was significantly larger than that at baseline (P < 0.05). The range of motion of knee joint at postoperative 6 months was significantly larger than that at postoperative 1 month (P < 0.05). The range of motion of knee joint at postoperative 1 and 6 months in the minimally invasive group was significantly larger than that in the open group (P < 0.05). (6) The Lysholm and International Knee Documenting Committee scores at postoperative 1 month in both groups were significantly higher than those at baseline (P < 0.05). The scores at postoperative 6 months were significantly higher than those at postoperative 1 month (P < 0.05). The scores at postoperative 1 and 6 months in the minimally invasive group were significantly higher than those in the open group (P < 0.05). (7) These findings suggest that the patients in both groups after undergoing surgical methods had restored motion of range with time going. Compared with open fixation, arthroscopic reduction and Fiber Tape circular fixation for treating tibial eminence fracture has less blood loss, less trauma, shorter recovery time and higher functional recovery. [ABSTRACT FROM AUTHOR]

To alleviate road congestion, a smooth index feedback strategy of dual channel with two lanes of the road network model was proposed, which was based on a single export. With 3 kinds of traditional information feedback strategies on the comparison of road network model of traffic flow characteristic parameters influence, the superiority of the strategy index smooth feedback was explored. The simulation results showed that compared with the first three traditional information feedback strategies, under the smooth index feedback strategy, the average speed of vehicles, the number of vehicles and the traffic volume change steadily with time, and the road capacity were improved. [ABSTRACT FROM AUTHOR]

Precipitation is the important forcing data for hydrological models. However, the precision of hydrological modeling in many regions of the world is limited by the lack of precipitation data. To overcome such limitation, some available globally gridded high resolution precipitation datasets have been used to simulate runoff. Although these precipitation products have been proved to have certain accuracy and good potential for hydrologic simulation, selecting the most optimal precipitation product for certain regions is still important because the accuracy and hydrological utility of precipitation dataset vary in different regions. In this study, the suitability of three precipitation products: GLDAS, TMPA and ERA-Interim for hydrological modeling are evaluated using the multi-objective fuzzy optimum model and the Soil and Water Assessment Tool (SWAT) model during the period of 2001-2012 in the Huanren reservoir catchment, located in Hunjiang River of China. SWAT is a physical-based hydrological model, which takes precipitation series from gauged stations as input to simulate runoff. First, in order to obtain the rainfall time series for SWAT model, three interpolation methods, including inverse distance-weighted method, bilinear interpolation method and the nearest point method, were used to compute the station data from the three precipitation products. Then, the quantitative accuracy of these time series were assessed by statistical indices of mean error (ME), root mean square error (RMSE), correlation coefficient (CC) and relative bias (Bias). The multi-objective optimum fuzzy model aiming to identify the appropriate interpolation method and justify the precipitation products alternative to the gauged values was established, which used ME, RMSE, CC and Bias as characteristic indices. The results revealed that the precipitation of GLDAS cannot serve as an alternative due to its underestimation for the whole basin, which can increase the risk of flood control operation. Moreover, the bilinear interpolation was more appropriate to interpolate the grid precipitation to rain gauge compared with the inverse distance-weighted method and the nearest point method. In addition the precipitation of TMPA and ERA-Interim obtained with the bilinear interpolation method were proved to have perfect fitting with the gauge values at daily and monthly scale, thus they both were alternative to the gauge values as the forcing data to the hydrological model. The two precipitation series were then used as the input to the SWAT model that has been calibrated with rain gauge inputs to get the simulated stream flow and their Bias. Correlation coefficient and Nash-Sutcliffe efficiency coefficient (NSE) were calculated against the observed stream flow. Based on the criteria of the statistical indices specified in the present study, it can be concluded that the performances of these simulations were acceptable at daily and monthly scale. With Bias, CC and NSE as characteristic indices, the multi-objective optimum fuzzy model was developed to evaluation the suitability of TMPA and ERA-Interim for hydrological simulation. The results revealed that TMPA was more suitable for hydrological runoff modelling at the basin scale. The methodologies and approaches developed in the present study will be a reference for hydrological modelling of similar watersheds. [ABSTRACT FROM AUTHOR]

As an important contributor to carbon (C) flux in the global C cycle, fine root litter decomposition in forests has the potential to be affected by the elevated nitrogen (N) deposition observed globally. From November 2007 to January 2013, a field experiment involving monthly simulated deposition of N in a Pleioblastus amarus plantation was conducted in the Rainy Area of West China. Four levels of nitrogen deposition were included as control (0 g N . m-2 . a-1 ), low nitrogen (5 g N . m-2 . a-1 ), medium nitrogen (15 g N . m-2 . a-1 ) and high nitrogen (30 g N . m-2 . a-1). After 3 years of simulated N deposition experiment (January 2011), a two-year fine root decomposition experiment was conducted in the simulated N deposition plots using litterbag method, under monthly experimental N deposition. The decomposition rates of fine roots were fast first and then slow. Mass loss of fine roots in the first year of decomposition was up to 60%, and the change of the remaining mass was very slow in the second year. The time of 50% and 95% mass loss of fine roots was 1. 20 and 5. 17 years, respectively, under the conditions of no addition N input. In general, decomposition rates were underestimated using negative exponential model. Simulated N deposition significantly inhibited the decomposition of fine roots. The remaining mass in the high nitrogen treatment was 51. 0% higher than that in the control, after two years of decomposition. Simulated N deposition increased C, P and K contents in the remaining mass of litter. Compared with the control, soil pH decreased significantly in the medium and high nitrogen treatments, soil organic C, total N, ammonium and nitrate contents and fine root biomass of P. amarus increased significantly in the high nitrogen treatment after simulated N deposition for 4. 5 years. [ABSTRACT FROM AUTHOR]

The article presents a study which analyses the rainfall and actual rainfall in Huanren basin using the global forecast system (GFS). Results indicate that the GFS rainfall forecast is higher than without the consideration of forecast horizon weights. Moreover, proposed is a method that has greater significance for reservoir operation.

Based on the biological mechanism of immune algorithm, an improved immune genetic algorithm is proposed, in which particle swarm optimization is taken as global searching strategy to improve the global search ability of the immune genetic algorithm, and progressive optimization algorithm is used for evolving operation of control strategy to improve its local search ability. At the same time, because of self-regulatory mechanism of immune algorithm based on concentration, group diversity can be improved and algorithm can be avoided to fall into local optimal solution too early. The specific realization process of the algorithm is presented, as well as the algorithm is applied to optimal operation of a hydropower station, which indicates that the results are satisfied, including the effectiveness and superiority compared with dynamic programming, genetic algorithm, immune algorithm and particle swarm optimization. [ABSTRACT FROM AUTHOR]

The research trend of FA inhibitions on nitrifies were introduced, including the inhibition mechanism and inhibition mathematic model of ammonia-oxidizing bacteria and nitrite-oxidizing bacteria, as well as the strategy to reduce or avoid inhibition effects. In addition, the selective inhibition effects of FA on the start-up and stability of partial nitrification were illuminated. In particular, the combinative effects of FA inhibition and other factors (such as dissolved oxygen and temperature) on short-cut nitrification were presented in the review. [ABSTRACT FROM AUTHOR]

Partial nitritation is the basis of anoxic ammonium oxidation (Anammox), however, very limited research has been undertaken on this field. In this study, an A/O reactor was used to investigate the feasibility of the partial nitritation and the performance of biological phosphorus removal from municipal wastewater. The obtained results showed that the partial nitritation could be achieved in A/O reactor with nitrite accumulation rate of 85%. It was possible that nitrite-to-ammonium ratio in the effluent from the A/O reactor was approximately controlled at 1.0 by adjusting hydraulic retention time, which was beneficial to the Anammox reaction. The fluctuation of temperature and DO concentration might lead to the deterioration of nitritation. After the achievement of partial nitritation, the biological phosphorus removal was not stable, which might relate to the increase of FNA concentration in the effluent of A/O reactor, and needed further experimental investigation. [ABSTRACT FROM AUTHOR]

Due to the superior forecasting performance, relevance vector machine (RVM) was applied to mid- and long-term runoff forecasting, and based on the phase space reconstruction, the runoff relevance vector machine forecasting model was established. Firstly, the runoff time series was reconstructed in the phase space, and the reconstructed series was as the proposed model input; Secondly, the particles swarm optimization (PSO) algorithm was applied to identifying the model parameters and chaotic properties of time series. The EM algorithm was used to estimate hyper-parameters in the inherent cycle, RVM was compared with widely used least squares support vector machine (LSSVM) and auto-regressive moving average model (ARMA). The test results show that the model has good generalization ability; Finally, in terms of the uncertainty of hydrological processes, the scheduling staffs consider the uncertainties in forecasting, and quantitatively estimate the risks and benefits in decision-making based, on the uncertainty of RVM output values and the probability forecast interval. [ABSTRACT FROM AUTHOR]

The inter-basin water transfer operation belongs to the conventional water transfer planning operation mode, and the real-time information is not considered in the operation. To solve this problem, the decision tree method in data mining is used combining the current reservoir forecast information, underlaying surface water storage condition, perennial reservoir running situation and other data with the reservoir managers' actual operation experiences, and then, the inter-basin water transfer real-time operation rules can be realized. Research process has three steps. Firstly, initial reservoir water level, actual rainfall, GFS forecasting rainfall, soil moisture, diversion water quantity, etc. are selected to compose the reservoir operation data set. Secondly, the inter-basin water transfer operation decision tree is extracted by using data mining technology. Finally, the operation decision tree is tested and the inter-basin water transfer real-time operation rules are obtained. The actual example results show that using decision tree inter-basin water transfer operation rules in the reservoir operating can increase the water resource efficiency and the reservoir comprehensive benefits. This research result has some reference value for the further study and application of the inter-basin water transfer real-time operation. [ABSTRACT FROM AUTHOR]

An orthogonal expansion of stochastic optimal polynomial control, employing the homogenous chaos decomposition with multidimensional Hermite polynomials of random variable argument, of Duffing oscillators is investigated. It reveals the essential relationship between evolution of polynomial coefficients and probabilistic characteristics of oscillator response and control force. The procedure is demonstrated on a base-driven system whereby the ground motion is modeled as a stochastic process with a specified correlation function and is approximated by its Karhunen-Loeve expansion. An adaptive scheme based on a displacement-velocity norm for stochastic approximation with polynomial chaos bases is proposed towards reducing com- putational effort, which is applied to the identification of phase orbits of nonlinear oscillators. This approximation is then in- tegrated into the design of an optimal polynomial controller, allowing for the efficient estimation of statistics and.probability density functions of quantities of interest. Numerical investigations are carried out employing the polynomial chaos expansion and the Lyapunov asymptotic stability condition based control policy. The results reveal that the performance, as gaged by probabilistic quantities of interest, of the controlled oscillators is greatly improved. It is remarked that the proposed polyno- mial chaos expansion is a preferred approach to the optimal control of nonlinear random oscillators. [ABSTRACT FROM AUTHOR]

To study the long-term effect of dissolved oxygen (DO) on phosphorus removal process, the characteristics of enhanced biological phosphorus removal (EBPR) under the DO level of 5.5 -7.0 mg/L and 0.5 - 1.5 mg/L were investigated systematically using sequencing batch reactor (SBR). The results showed that, when pH was in 7.2 - 7.6 and temperature was at (23 ± 0.5 ) °C , high DO had adverse impact on both phosphorus release process and phosphorus uptake process. The amount of released phosphorus in anaerobic period was 43.08% lower than that under low DO condition. Phosphorus uptake process went fast during the initial 30 rain in aerobic period. The maximum specific phosphorus uptake rate was 6.27, 11.45 mg ⋅ g-1 ⋅ h-1 under high DO and low DO conditions, respectively. Analysis indicated that the main reason of deterioration of phosphorus removal process was deficiency of poly - β - hydroxybutyrate (PHB) caused by excessive aeration and more influent carbon source used for densification process. High DO did not have obvious advantage on restraining filamentous sludge bulking than low DO. The improvement of phosphorus removal was usually associated with the improvement of sludge settleability. [ABSTRACT FROM AUTHOR]

The global searching performance of particle swarm optimization (PSO) algorithm is applied to the identification of the parameters of support vector machine (SVM) in which radial basis function (RBF) is used as kernel function. Before particle swarm searches the parameters, the parameters are transformed into exponent, which makes interval [0,1] and interval [1, ∞] have the same searching probability. Adaptive value function of PSO algorithm takes the generalization capability of SVM model as the criterion; thus two kinds of estimation of the generalization capability of SVM, the minimum error of testsamples and leave-one-out method, are discussed. Taking Yichang Station in Yangtze River as an example, ARMA model and seasonal ARIMA model, BP neural network model and the proposed SVM model are used to forecast the monthly discharge, respectively. The simulation and forecasting results show the effectivity of the proposed SVM model. [ABSTRACT FROM AUTHOR]

In order to solve the problem of sludge bulking which happened in wastewater treatment plant frequently, a notion named low DO limited filamentous bulking was put forward. It is a new energy-saving and high-efficient method to treat wastewater with the characteristics of morphology and physiology of filamentous bacteria under low DO concentration condition. The impact of DO concentration and organic loading rate (OLR) on sludge settleability and the removal characteristics of nitrogen, phosphorus and COD under limited filamentous bulking were investigated by using sequencing batch reactor (SBR) through operation in aerobic-anoxic pattern. The results show that OLR and DO concentration affect sludge settleability in special range respectively. When OLR is larger than 0. 25 d-1, limited filamentous bulking state can not be maintained by low DO concentration alone. Nitrification will not be deteriorated under low DO limited filamentous bulking condition, and about 20% nitrogen is removed through simultaneous nitrification and denitrification (SND) based on the mass balance of nitrogen. Aerobic phosphorus release is found in the initial stage of low aeration rate, and the system can enrich phosphorus accumulating organisms (PAOs). [ABSTRACT FROM AUTHOR]

Tightly coupling business unit with process logic makes graph-theory-based multireservoirs flood forecast and control system (GMRFFCS) less general and extensible. So the primary goal is to form a general multi-reservoir business component by improving the existing codes in business layer with refactoring technique. First, business unit and process logic are separated from business layer for reusing and recombining. Second, aparallel algorithm for topological sort in directed graphs is adopted to increase computing speed. Then,developing system based on this component can make the developer pay more attention to the researches on models of forecasting and operation without graph theory. At last,integration with existing systems is referred. Results show that refactoring business layer greatly improves the GMRFFCS' general utilization. [ABSTRACT FROM AUTHOR]

According to the principle of physical stochastic optimal control, a novel stochastic optimal control strategy is developed in the context of optimal polynomial control that is well-adapted to nonlinear stochastic dynamical systems. Duffing oscillators with varying levels of nonlinearity, subjected to random ground motions, are investigated for illustrative purposes. Numerical results indicate that the statistical variability of system responses gains an obvious reduction, and the system performance improves significantly after the optimal polynomial controller is mounted. Using the control criterion with the minimum of the exceedance probability of system quantities in energy trade-off sense, the lst-order controller suffices even for strongly nonlinear systems. This bypasses the need to utilize nonlinear controllers which may be associated with dynamical instabilities due to time delay and computational dynamics. Besides, the optimal polynomial controller exhibits high robustness to the levels of nonlinearity of Duffing oscillators. The classical statistical linearization based LQG, however, using the nominal Gaussian white noise as the external excitation does not have this advantage. [ABSTRACT FROM AUTHOR]

The shift of nitrifier population within a partial nitrification reactor was investigated using fluorescence in-situ hybridization (FISH) techniques and the floc morphology was observed using scan electron microscope (SEM). Partial nitrification to nitrite was achieved quickly by using real-time aeration duration control when domestic wastewater was treated in a lab-scale sequencing batch reactor (SBR). The average nitrite accumulation ratio was above 93%. The morphology photographs observed using SEM indicated that the sludge showed a shift towards spherical and small rod-shaped clusters from the diverse morphology. FISH analysis showed that ammonia-oxidizing bacteria (AOB) gradually out-competed nitrite-oxidizing bacteria (NOB). AOB population percentage increased from 3.5% (during the start-up period) to 8.5% (after achieving nitritation for 102 days), while NOB population percentage decreased from 3.1% to less than 0. 5%. Accordingly, the long-term operation with the use of real-time aeration duration control was not only favorable for AOB community optimisation, but also for the achievement of partial nitrification in practice. [ABSTRACT FROM AUTHOR]

Based on summarizing the current progresses and existing problems in basin-wide flood control decision-making system in China, a new flood operating system with B/S + C/S mixed mode was developed. In this system, Hibernate technique is used for dividing business layer and database. Bridge Mode is used to separate interface and business operation. Proxy technique serves for managing system users/ authorities. Comparing with other current systems, the new system not only promotes efficiency by reducing close links among interfaces, business operation, system users authorities and database, but also reduplicates software programming. The successful application of these techniques to Liao-Hun-Tai River Basin flood control decision-making support system shows that this system can be easily removed, extended and used in other systems. [ABSTRACT FROM AUTHOR]

The combination of chromatogram and chemical analysis was adopted to optimize the methods selected to measure poly - P, glycogen and PHA intracellular polymer in EBPR system. PHA was measured by GC system, glycogen was degraded by dilute hydrochloric acid and analyzed by glucose commercial kit, and poly - P was oxidized by potassium persulfate and analyzed by molybdenum - antimony anti-spectrophotometric method. Testing of the proposed method for PHA analysis shows that 4% sulfuric acid concentration and degradation for 20 h are required for optimal PHB and PHV extraction, while 0.6 mol/L HCl and digestion for 5 h produce the highest recovery of glycogen, and the medical glucose kit can be used in this research. Oxidation for 30 min at 120 °C is recommended for the recovery of poly - P. The results of precision analysis and recovery test with standard addition of these methods show that they possess high precision and are convenient for laboratory research and practical application. [ABSTRACT FROM AUTHOR]

Several design patterns in software engineering were studied for the purpose of applying them to the system of flood forecast and operation (SFFO). The bridge pattern was employed to design the architecture of SFFO and the data access; the Strategy pattern was used to manage the models of SFFO; the iterator pattern and the decorator pattern were employed in the alternatives management; the proxy pattern was used for managing the users authorities; and the singleton pattern was used for the database connection pool. The patterns used in the software can achieve the loose coupling relationship between different modules and increase the maintainability and reusability of SFFO. Two types of display interfaces, Web browser and Java window, were developed in this system. When SFFO is running, it can choose the communication manner automatically and interact with the functional module of system business logic according to the operating environment. [ABSTRACT FROM AUTHOR]

Based on digital image processing, the relationship between homogeneity and uniaxial compressive strength, splitting strength as well as shear strength of asphalt mixture was quantitatively investigated by dint of the index of homogeneity. The results show that homogeneity has no direct and obvious relationship with the absolute value of mechanical properties of asphalt mixture, but it does with the variation of mechanical properties; the variation of mechanical properties is great for the asphalt mixture with worse homogeneity, while it is slight for the asphalt mixture with better homogeneity. It is indicated that the variation control of mechanical properties of asphalt mixture is significant for the homogeneity control of asphalt mixture. [ABSTRACT FROM AUTHOR]

This paper discussed how to arrange fleet maintenance process and accelerate repair speed in order to improve company's competitive ability. Based on the fact that the assets need to be disassembled before repair and different servicemen have different repair speed to different part, a maintenance decision method was provided which is based on time optimization. There is no requirement to the number of tasks for any serviceman, called unbalanced task assignment. Also a genetic algorithm was developed to solve this NP-hard problem and discussed its convergence. The numerical example shows that the algorithm is feasible. [ABSTRACT FROM AUTHOR]

The energy consumption of the test and control system in automatic vertical drilling tools is provided by the downhole turbine generator. In order to make downhole turbine generator adapt to mud working condition, we combined the dynamic sealing compensation protection technology with the magnetic driving technology, and achieved good results in improving the dynamic sealing reliability, increasing the service life of high speed bearings, improving generator efficiency, and avoiding the generator coil and the magnet steel from being eroded by mud. The design of this turbine generator covers not only the design of the performance and structure parameter of the generator itself, but also the related parameter design of the magnetic driver and the compensation spring, one of the dynamic sealing compensation protection components. The paper gives a design method for the magnetic driver of downhole turbine generator, and discusses the spring design of the dynamic sealing compensation protector. [ABSTRACT FROM AUTHOR]

The influences of concentration of sodium percarbonate and oxygen bleaching activator TAED, bleaching temperature and time on the whiteness, strength and damage of cotton/wool blended yarn were investigated. The optimum bleaching process of cotton/wool blended yarn with sodium percarbonate was scouring agent 4 g/L, sodium percarbonate 6 g/L, oxygen bleaching activator TAED 4 g/L, Na2SiO3l g/L, bleaching at 80 °C for 60 min. The whiteness of sodium percarbonate bleaching was same as that of traditional hydrogen peroxide bleaching, and the loss of strength and wool content of cotton/wool blended yarn was less than that of traditional hydrogen peroxide bleaching. [ABSTRACT FROM AUTHOR]

After analyzing series monitoring data of micro-seismic and powered support pressure in Xinjiang,rock-burst mechanism was obtained. Thick and hard roof is main pressure source of rock-burst. Bad and delayed supporting make roof pressure transferred on coal-wall ahead of mining face. Thus, elastic energy and stress concentration formed, and fast mining speed aggravates energy and stress concentration degree. In this instance, rock-burst is inevitable because of strong burst liability of coal-seam. Based on this, rock-burst prevention principle was established that avoiding transferring hard and thick roof pressure to coal-wall. The prevention methods included broken blasting of hard roof, pressure-relief blasting of coal-body and increasing setting load of powered supports. The practice shows that prevention methods are effective. [ABSTRACT FROM AUTHOR]