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Aiming at the potato soil separation device of potato harvester, which generally has the problem of potato high damage in potato-soil separation, a three-stage potato soil low-loss separation device was developed, and orthogonal experiments were designed with the help of RecurDyn-EDEM coupled simulation method. A field bench was built for verification tests. The test proved that: when the lift transport chain speed was 1.40 m/s, travel speed was 0.60 m/s, amplitude was 32.0 mm, the impurity rate was 1.49% and the average force on potato was 1.801 N. The potato damage rate was 2.7%, indicating that the design of the three-stage potato soil low-loss separator device worked well. [ABSTRACT FROM AUTHOR]

In this paper, we consider the distributed estimation problem of a linear stochastic system described by an autoregressive model with exogenous inputs when both the system orders and parameters are unknown. We design distributed algorithms to estimate the unknown orders and parameters by combining the proposed local information criterion with the distributed least squares method. The simultaneous estimation for both the system orders and parameters brings challenges for the theoretical analysis. Some analysis techniques, such as double array martingale limit theory, stochastic Lyapunov functions, and martingale convergence theorems are employed. For the case where the upper bounds of the true orders are available, we introduce a cooperative excitation condition, under which the strong consistency of the estimation for the orders and parameters is established. Moreover, for the case where the upper bounds of true orders are unknown, a similar distributed algorithm is proposed to estimate both the orders and parameters, and the corresponding convergence analysis for the proposed algorithm is provided. We remark that our results are obtained without relying on the independency or stationarity assumptions of regression vectors, and the cooperative excitation conditions can show that all sensors can cooperate to fulfill the estimation task even though any individual sensor cannot. [ABSTRACT FROM AUTHOR]

This paper considers the consensus decision-making problem of spatially distributed multiagent systems with multiple leaders, where the leaders have the preference about the destination, while the followers have no such preference. The agents have limited capability to sense the movement information of their local neighbors determined via the spatial relative distance, and make movement decisions accordingly. The objective is to guide the followers to move with the same preferred direction as leaders have (i.e., reaching a stable consensus). We provide detailed analysis for the information transfer between the subgroups of leaders and followers, and establish quantitative results on the proportion of leaders needed to reach the stable consensus for two cases: leaders with the same preference and leaders with different preferences. For the system where the leaders have the same preference, we provide an upper bound (impossibility theorem) and a lower bound (sufficient condition) for the proportion of leaders needed in reaching the stable consensus. When the leaders have two different preferences, we provide a sufficient condition and a necessary condition on the proportions of two subgroups of leaders to achieve stable consensus decisions. [ABSTRACT FROM AUTHOR]

CO2-responsive and photopolymerizable prepolymers are designed and synthesized. Their good photopolymerization kinetics and reversible CO2 and N2 responses to a bulk state and in a solution are reported. Stepwise modulation is verified in template imprinting. Results reveal that stable and high-resolution patterns can be produced by imprinting liquid prepolymers in CO2 atmosphere, erased by warm heating, or retained permanently by chemical cross-linking through photopolymerization with the aid of a photoinitiator. By contrast, only blurry patterns are obtained in air. [ABSTRACT FROM AUTHOR]

In this study, the authors study the power control for a two-tier network system which is comprised of a central macrocell and several femtocells. In practice, the communication environment is fairly complex and dynamic which leads to the imperfect channel state information (CSI). To enhance the robustness of the two-tier network system, the imperfect CSI in both signal links and interference links are considered and the uncertainties of the CSI are uniformly distributed in an ellipsoid uncertainty set. Then, a probability-constrained optimisation problem is formulated to deal with the uncertainties and protect the quality-of-service of all users. A novel method is provided to convert probability constraints into deterministic ones. Based on them, they propose an iterative algorithm and an admission control algorithm to enhance the network efficiency. They also investigate the case when the distributions of the uncertainties of the CSI are unknown. Finally, numerical results are given to illustrate the effectiveness of the authors' power control scheme. [ABSTRACT FROM AUTHOR]

A central and fundamental issue in the theory of complex systems is to understand how local rules lead to collective behavior of the whole system. This paper will investigate a typical collective behavior (synchronization) of a self-propelled particle system modeled by the nearest neighbor rules. While connectivity of the dynamic neighbor graphs associated with the underlying systems is crucial for synchronization, it is widely known that the verification of such dynamical connectivity is at the core of theoretical analysis. Ideally, conditions used for synchronization should be imposed on the model parameters and the initial states of the particles. One crucial model parameter is the interaction radius, and we are interested in the following natural and basic question: What is the smallest interaction radius for synchronization? In this paper, we will show that, in a certain sense, the smallest possible interaction radius approximately equals √log n/(πn), with n being the population size, which coincides with the critical radius for connectivity of static random geometric graphs known in the literature. [ABSTRACT FROM AUTHOR]

In this short paper, it is proved that every pair of large positive odd integers satisfying some necessary conditions can be represented in the form of a pair of one prime, two prime squares and k powers of 2. In particular, we have k -- 332. [ABSTRACT FROM AUTHOR]

This paper investigates the synchronization behavior of a class of flocks modeled by the nearest neighbor rules. While connectivity of the associated dynamical neighbor graphs is crucial for synchronization, it is well known that the verification of such dynamical connectivity is the core of theoretical analysis. Ideally, conditions used for synchronization should be imposed on the model parameters and the initial states of the agents. One crucial model parameter is the interaction radius, and we are interested in the following natural but complicated question: What is the smallest interaction radius for synchronization of flocks? In this paper, we reveal that, in a certain sense, the smallest possible interaction radius approximately equals ;√log n/(πn), with n being the population size, which coincides with the critical radius for connectivity of random geometric graphs given by Gupta and Kumar [Critical power for asymptotic connectivity in wireless networks, in Stochastic Analysis, Control, Optimization and Applications, Birkhäuser Boston, Boston, MA, 1999, pp. 547-566]. [ABSTRACT FROM AUTHOR]

In this paper, we prove that, with at most O( N) exceptions, all positive integers n ⩽ N can be written as sums of a cube and four cubes of primes. [ABSTRACT FROM AUTHOR]

This paper studies compress-forward (CF) coding with BPSK modulation for the half-duplex Gaussian relay channel. In CF relaying, Wyner-Ziv coding is applied at the relay to exploit the joint statistics between signals at the relay and the destination. We propose Slepian-WoIf coded nested scalar quantization (SWCNSQ) for practical Wyner-Ziv coding at the relay. We first provide the achievable rate of SWCNSQ based CF relaying as a performance benchmark, and then present a practical code design using low-density parity-check (LDPC) codes for error protection at the source, and nested scalar quantization plus irregular-repeat accumulation (IRA) codes for CF coding at the relay. The degree distributions of the LDPC and IRA codes are optimized using extrinsic information transfer charts and Gaussian approximation. Under discretized density evolution for asymptotically large block lengths, our optimized code design operates 0.11-0.21 dB away from the SWCNSQ limit for CF relaying. Simulations with LDPC/IRA codes of length 2 x 105 bits show a performance gap of 0.27-0.38 dB from the achievable rate. [ABSTRACT FROM AUTHOR]

A set of original jobs has been scheduled on a single machine, but not processed, when a set of new jobs arrives. The decision maker needs to insert the new jobs into the existing schedule without excessively changing it. The objective is minimization of the maximum lateness of the jobs, subject to a customer service requirement modeled by a limit on the maximum time change of the original jobs. Because the schedule of the original jobs can be arbitrary this problem models multiple disruptions from repeated new job arrivals. We show that this scheduling problem is intractable, even if no new jobs arrive. We describe several approximation algorithms and analyze their worst-case performance. Next, we develop a branch and bound algorithm that uses a variable neighborhood descent algorithm to obtain an initial upper bound, several dominance properties that we establish, and a lower bounding scheme based on a preemptive relaxation of the problem. The branch and bound algorithm solves 99.9% of randomly generated instances with up to 1,000 jobs within 60 CPU seconds. Our work demonstrates for the first time that optimization of large scale, intractable rescheduling problems is possible. More generally, it refocuses the literature on scheduling problems towards rescheduling issues. [ABSTRACT FROM AUTHOR]

Nested lattice quantization provides a practical scheme for Wyner-Ziv coding. This paper examines the high-rate performance of nested lattice quantizers and gives the theoretical performance for general continuous sources. In the quadratic Gaussian case, as the rate increases, we observe an increasing gap between the performance of finite-dimensional nested lattice quantizers and the Wyner-Ziv distortion-rate function. We argue that this is because the boundary gain decreases as the rate of the nested lattice quantizers increases. To increase the boundary gain and ultimately boost the overall performance, a new practical Wyner-Ziv coding scheme called Slepian-WoIf coded nested lattice quantization (SWC-NQ) is proposed, where Slepian-Wolf coding is applied to the quantization indices of the source for the purpose of compression with side information at the decoder. Theoretical analysis shows that for the quadratic Gaussian case and at high rate, SWC-NQ performs the same as conventional entropy-coded lattice quantization with the side information available at both the encoder and the decoder. Furthermore, a nonlinear minimum mean-square error (MSE) estimator is introduced at the decoder, which is theoretically proven to degenerate to the linear minimum MSE estimator at high rate and experimentally shown to outperform the linear estimator at low rate. Practical designs of one- and two-dimensional nested lattice quantizers together with multilevel low-density parity-check (LDPC) codes for Slepian-WoIf coding give performance close to the theoretical limits of SWC-NQ. [ABSTRACT FROM AUTHOR]

Aiming at the traditional peanut planter seed and fertilizer sowing depth inconsistency caused by seed burning and injury, fertilizer waste and low seed emergence rate, the design of a peanut planter with high-speed operation and controllable seed and fertilizer sowing depth was performed. The laser sensor is added to detect the height of the ridge and the furrow opener position feedback, and the speed sensor detects the operating speed of the peanut planter. The mechanical analysis of the four-link rod clarifies the control principle, improves the PID algorithm of the integral term, designs the control strategy based on the operating speed of the planter, controls the electro-hydraulic system, and realizes the sowing and fertilizing depth adjustment of the furrow opener. Through the design of three-factor three-level orthogonal simulation test, it is concluded that the vehicle speed and height deviation value are significant factors affecting the sowing and application depth, and under the verification of the field test, it is obtained that when the sowing depth is 50 mm under the speed of 3 km/h, the dynamic sowing depth qualification rate is 96.26%, and the maximum coefficient of variation of the sowing depth is 2.58%, which improves the effect of the existing control of the sowing depth of the peanut by 6.05%, and reduces the variation of the sowing depth by 2.85%. The research has demonstrated superior performance compared to traditional mechanical adjustment in regulating the planting depth of peanuts, thereby achieving the intended design objective. [ABSTRACT FROM AUTHOR]

Aiming at the problems of low threshing efficiency and high damage rate of current threshing devices. In this study, the operational form of the threshing drum and the structure of the threshing element were innovated, and a new threshing drum with low damage and high efficiency was designed. Using EDEM software, flexible body modeling of corn kernels, cobs and whole ears was carried out. The dynamic analysis of the corn threshing process was completed and the simulation parameters were further optimized. The optimum operating parameters were analyzed by orthogonal rotational tests and response surface method with a speed of 800 r/min for the threshing drum, a clearance of 10 mm for the concave plate and 30 mm for the threshing drum. The radius of the round head of the threshing element was 5 mm. The height of the threshing element was 60 mm. The final threshing efficiency was 98.78% and the damage rate of threshing was 0.62%. The results show that the new threshing device can meet the requirements of low-loss threshing devices for corn combine harvesters and can provide a theoretical basis for the development of the theory and technical system of corn plot combine harvesters in the future. [ABSTRACT FROM AUTHOR]

This paper presents a numerical study on the dynamic responses of the non-ballast track structures under the high-speed train load that is excited by the rail irregularity at the welded rail joint. In this study, a multi-body dynamics model with 10 degrees of freedom is built to model a high-speed vehicle and a finite element model is established to simulate the non-ballast track. A mathematical model is also given to characterize the geometry of the local rail irregularity at the welded rail joint. By coupling the high-speed vehicle model and the track model and taking the mathematical model of the welded rail joint as an input, the dynamic responses of the non-ballast track structures under a rail vehicle running at a high speed are simulated and discussed in this paper. The wheel/rail force and the rail and slab vibration acceleration are investigated to demonstrate the significant dynamic effects on the track structures due to the welded rail joint. [ABSTRACT FROM AUTHOR]

Background: Delayed Matching-to-Sample Task 48 (DMS48), a brief tool measuring visual recognition memory, is valid to identify the early stage of Alzheimer's disease (AD) in Caucasians. However, little data is available in Chinese.Objective: To develop norms and optimal cutoff points for the DMS48 in Chinese elders.Methods: A cross-sectional study was conducted in seven memory clinics from five cities across China. DMS48 was applied to 369 Chinese aged 50 or older (138 cognitively normal [CN], 112 mild cognitive impairment due to AD (MCI-A), and 119 mild AD dementia). The demographic factors which influence DMS48 scores were investigated and the norms were established considering those factors. Receiver operating characteristic (ROC) analysis was used to determine the optimal cutoff points.Results: Age was shown to influence DMS48 scores (r = -0.36, p < 0.05), and we presented the age-stratified normative data for the DMS48. The optimal cutoff point is 42/43 for identifying cognitive impairment (MCI-A and AD dementia) against CN (sensitivity 97.80% and specificity 89.13%) and MCI-A against CN (sensitivity 86.60% and specificity 94.20%). A cutoff of 39/40 obtained good sensitivity (100.00%) and specificity (94.90%) in discriminating AD dementia from CN. The age-stratified optimal cutoff points for identifying MCI-A were 43/44 for individuals aged 50 to 59 years old, 42/43 for 60 to 69 years old, 41/42 for 70 to 79 years old, and 40/41 for 80 or older, respectively (sensitivity 84.80% and specificity 95.70%).Conclusion: This study proved that DMS48 is of good validation in screening MCI-A in elderly Chinese. [ABSTRACT FROM AUTHOR]

For online education platforms, a personalized recommendation system is crucial, and the collaborative filtering algorithm is the primary recommendation algorithm used. This study took the recommendation of crowdfunding platforms as a sample, and enhanced the collaborative filtering algorithm based on the user score and project attribute features of the crowdfunding platform, intending to resolve the cold start issue brought on by the platform's reliance on a single data source. The study concludes with experimental proof of the paper's suggested better method. This approach can alleviate the cold start issue to some degree. The prediction accuracy has been much enhanced in comparison with the conventionally advised method. The method can also adapt to user tastes over time, learning what they like and what they don't. It also has an excellent real-time suggestion impact. The performance verification of the algorithm in this research is also conducted using data from a live crowdfunding site, lending credence to the study's claim of greater practicality. [ABSTRACT FROM AUTHOR]

All-optical format conversion from inverse-return-to-zero (inverse-RZ) to non-return-to-zero (NRZ) is realized by using a half-bit-delay Mach-Zehnder delay interferometer. Experimental results demonstrate that the converted NRZ signal has better receiver sensitivity than the back-to-back inverse-RZ signal. [ABSTRACT FROM AUTHOR]

Plastid-to-nucleus retrograde signaling plays an important role in regulating the expression of photosynthesis-associated nuclear genes (PhANGs) in accordance with physiological demands on chloroplast biogenesis and function. Despite its fundamental importance, little is known about the molecular nature of the plastid gene expression (PGE)-dependent type of retrograde signaling. PGE is a multifaceted process, and several factors, including pentatricopeptide repeat (PPR) proteins, are involved in its regulation. The PPR protein GUN1 plays a central role in PGE-dependent retrograde signaling. In this study, we isolated a mutant exhibiting up-regulation of CHLOROPHYLL A/B-BINDING PROTEIN (CAB) under normal growth conditions (named coe1 for CAB overexpression 1). The coe1 mutant has a single-base mutation in the gene for mitochondrial transcription termination factor 4 (mTERF4)/BSM/RUG2, which plays a role in regulating the processing of certain plastid transcripts. Defects in GUN1 or mTERF4 de-repressed the expression of specific plastid mRNAs in the presence of lincomycin (LIN). In wild-type plants, treatment with LIN or spectinomycin (SPE) inhibited processing of plastid transcripts. Comparative analysis revealed that in gun1 and coe1/mterf4, but not in wild-type, gun4, or gun5 plants, the processing of plastid transcripts and expression levels of Lhcb1 mRNA were affected in opposite ways when plants were grown in the presence of LIN or SPE. In addition, the coe1 mutation affected the intracellular accumulation and distribution of GUN1, as well as its plastid signaling activity. Taken together, these results suggest that GUN1 and COE1 cooperate in PGE and retrograde signaling. [ABSTRACT FROM AUTHOR]

A series of AgBr/TiO2 visible photocatalysts with heterojunction structure was synthesized using Ti(OC4H9)4,KBr,and AgNO3 as precursors. The phase composition, particle morphology and size, microstructures, and absorbance of these photocatalysts were characterized by X-ray diffraction, transmission electron microscope (TEM), high-resolution TEM, and UV-vis spectra. It was found that the coupled AgBr/TiO2 was an effective photocatalyst to degrade the methylene blue under visible light irradiation, compared with the other noncoupled photocatalysts of AgBr, AgBr/P25, and P25. The photocatalytic activities of AgBr/TiO2 increase first and then decrease with increasing the mass ratio of mAgNO3/mTiO2 and the photocatalyst with the mass ratio of 3.35 has the highest photocatalytic activity. The results showed that the coupled photocatalyst has the particle size of about 15 nm with homogeneous dispersion and has the strongest absorption in whole UV-vis light region (250~800 nm) originated from the synergetic effect of heterostructured AgBr/TiO2. The coupled AgBr/TiO2 photocatalyst can keep stable photocatalytic activity after five-circle runs. [ABSTRACT FROM AUTHOR]

This work proposes three switched control strategies for aggregated heating, ventilation, and air conditioning (HVAC) systems in commercial buildings to track the automatic generation control (AGC) signal in smart grid. The existing control strategies include the direct load control strategy and the setpoint regulation strategy. The direct load control strategy cannot track the AGC signal when the state of charge (SOC) of the aggregated thermostatically controlled loads (TCLs) exceeds their regulation capacity, while the setpoint regulation strategy provides flexible regulation capacity, but causes larger tracking errors. To improve the tracking performance, we took the advantages of the two control modes and developed three switched control strategies. The control strategies switch between the direct load control mode and the setpoint regulation mode according to different switching indices. Specifically, we design a discrete-time controller and optimize the controller parameter for the setpoint regulation strategy using the Fibonacci optimization algorithm, enabling us to propose two switched control strategies across multiple time steps. Furthermore, we extend the switched control strategies by introducing a two-stage regulation in a single time step. Simulation results demonstrate that the proposed switched control strategies can reduce the tracking errors for frequency regulation. [ABSTRACT FROM AUTHOR]

This paper obtains optimal power allocation to the data aggregator units (DAUs) and relays for cognitive wireless networks in a smart grid (SG). Firstly, the mutual interference between the primary user and the DAU are considered, and the expressions of the DAU transmission signal are derived based on the sensing information. Secondly, we use the particle swarm optimization (PSO) algorithm to search for the optimal power allocation to minimize the costs to the utility company. Finally, the impact of the sensing information on the network performance is studied. Then two special cases (namely, that only one relay is selected, and that the channel is not occupied by the primary user) are discussed. Simulation results demonstrate that the optimal power allocation and the sensing information of the relays can reduce the costs to the utility company for cognitive wireless networks in a smart grid. [ABSTRACT FROM AUTHOR]

The effects of exogenous growth regulating substance on the fruit weight of peach were reviewed. Paclobutrazol could increase the single fruit weight in different degree, and cytokinins could also increase the single fruit weight. GA3 and B9 had no effect on fruit size or on reducing single fruit weight. Chlorflurenol-methy, ABT and salicylic acid had no effect on fruit size. Suggestions on the future re¬search were put forward. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the anti-tumor effect of apogossypolone (ApoG2) on human LNCaP cells in vitro and in vivo. Cell viability was evaluated using an MTT assay. Cell autophagy and apoptosis were detected by flow cytometry and using a terminal deoxynucleotidyl transferase dUTP nick end labeling assay, respectively. Morphological autophagy alterations were observed by transmission electron microscopy. The formation of acidic vesicular organelles was assessed by acridine orange staining and fluorescence microscopy. Quantitative polymerase chain reaction (qPCR) was conducted to detect the expression levels of apoptosis-associated protein B-cell lymphoma 2 (Bcl-2) and Bak. The models of transplantation tumors in nude mice were established via subcutaneous injection of LNCaP cells. Growth of LNCaP cells was inhibited by ApoG2 treatment. Flow cytometry demonstrated that ApoG2 induced apoptosis in LNCaP cells. The Bcl-2 expression was decreased while Bak expression was increased. In addition, activation of cysteine aspartate protease (caspase)-3 and -8 was observed and 3-methyladenine (3-MA) enhanced apoptosis of LNCaP cells. Furthermore, nude mice treated with ApoG2 demonstrated a significant decrease in tumor volume and a significant increase in cell viability. Immunohistochemical analysis of tumor tissues demonstrated that ApoG2 enhanced caspase-3, -8, LC-3B and beclin-1 expression and reduced the expression of Bcl-2. ApoG2 was able to effectively suppress the growth of LNCaP cells through the induction of autophagy and apoptosis. [ABSTRACT FROM AUTHOR]

This paper addresses the attitude tracking control for spacecraft formation with delay free and communication delays. With help of the idea of sliding control, an adaptive attitude synchronization control architecture is established. Furthermore, by introducing a nonsmooth feedback function, a new class of nonlinear controllers for the attitude tracking of spacecraft is developed. Both parameter uncertainties and unknown external disturbances are dealt with via the kind of controllers. Finally, some simulation results are given to demonstrate the effectiveness and advantages of the proposed results. [ABSTRACT FROM AUTHOR]

Background: Maintenance therapy for non-small cell lung cancer (NSCLC) aims to extend disease control after first-line chemotherapy with active and well-tolerated agents. The utility of continuation maintenance therapy requires further research. Methods: This multicenter, randomized, phase 2 study compared continuation maintenance therapy with pemetrexed (500 mg/m2 every 21 days) and best supportive care (BSC) versus BSC alone in patients with advanced, non-squamous NSCLC who had not progressed after 4 cycles of induction chemotherapy with pemetrexed (500 mg/m2) and cisplatin (75 mg/m2). The primary endpoint was progression-free survival (PFS) from randomization, was analyzed using a Cox model, stratified for the tumor response at the end of induction therapy, at a one-sided alpha of 0.2. Secondary endpoints: response and disease control rates, overall survival (OS), one year survival rates, and treatment-emergent adverse events (TEAEs). Results: A total of 106 patients commenced induction therapy, of whom 55 patients were randomized to maintenance pemetrexed/BSC (n = 28) or BSC (n = 27). Although the median PFS time for maintenance phase for both arms was 3.2 months, the one-sided p-value for the PFS HR comparison was less than the prespecified limit of 0.2 (HR = 0.76, two-sided 95% confidence interval [CI]: 0.42 to 1.37; one-sided p-value = 0.1815), indicating that PFS was sufficiently long in the pemetrexed/BSC arm to warrant further investigation. Similar PFS results were observed for the overall study period (induction plus maintenance) and when the PFS analysis was adjusted for sex, baseline disease stage, and the ECOG PS prior to randomization. The median OS for the maintenance phase was 12.2 months (95%CI: 5.6 to 20.6) for the pemetrexed/BSC arm and 11.8 months (95% CI: 6.3 to 25.6) for BSC arm. The one-year survival probabilities were similar for both arms for the maintenance phase and the overall study period. Both the induction and continuation maintenance therapies were generally well-tolerated, and similar proportion of patients in each arm experienced at least 1 grade 3/4 TEAE (pemetrexed/BSC, 17.9%; BSC, 18.5%). Conclusions: Continuation pemetrexed maintenance therapy resulted in promising PFS with an acceptable safety profile in a Middle Eastern population with advanced non-squamous NSCLC and is worthy of further investigation [ABSTRACT FROM AUTHOR]

In order to suppress RNA silencing, many plant and some animal viruses encode RNA silencing suppressors to achieve infection. In this study, we report that B3 and B4, encoded by DNA3 and DNA4 of banana bunchy top virus (BBTV), exhibit RNA silencing suppression activity. B3 and B4 were able to increase the transient expression of green fluorescent protein (GFP) and dramatically enhanced the pathogenicity of potato virus X (PVX) in Nicotiana benthamiana. B4 was able to reverse established gene silencing on an inoculated leaf or on an upper leaf. B3, however, was only active during infection of an inoculated leaf. Furthermore, B4, but not B3, was able to enhance GFP expression in the transgenic N. benthamiana line 16c. In conclusion, B3 and B4 are the RNA silencing suppressors of BBTV, and they may act at different steps in the RNA silencing pathways. [ABSTRACT FROM AUTHOR]

The red tide in Hongsha Bay caused by Skeletonema costatum (S. costatum) from April 27 to May 4, 2006, was monitored in this study. The dynamic variety of environmental factors, including chlorophyll a (chl a), temperature, salinity, pH, dissolved oxygen, chemical oxygen demand, nitrate, ammonium, nitrite, phosphate (PO3-4), silicate, and iron (Fe), was observed and analyzed during the red tide in Hongsha Bay for the first time. The results indicated that the concentration of dissolved inorganic nitrogen was high (26.34 ¿mol/L) in Hongsha Bay. Because of the heavy rainfall from April 13 to 15, a large input of nutrients surged into the bay, causing an increase in the concentration of various nutrients, especially PO3-4, which showed an obvious increase (from 0.72 to 1.45 ¿mol/L). The abundant nutrients provided fundamental nutrient supply for the rapid proliferation of S. costatum. Three critical environmental factors, including water temperature, and PO3-4 and Fe concentration, played an important role in this red tide. Water temperature had a significant positive correlation with chl a. The water temperature shift was one of the critical environmental factors affecting the S. costatum red tide in Hongsha Bay. With the occurrence of the red tide, the concentration of PO3-4 rapidly decreased. Inorganic PO3-4 was rapidly depleted at the blooming stage, causing the red tide to gradually dissipate. Phosphate was the limiting factor of S. costatum proliferation in this red tide. Iron was also a factor. Salinity shift had little effect on the growth of S. costatum. [ABSTRACT FROM AUTHOR]

This paper studies the congestion control in ATM network as a stochastic optimal control problem. Based on the first equivalent controller presented in Automatica 35(12) (1999), 1937–1950, the modified linear quadratic guass (MLQG) control is introduced to control over long-range dependence networks. In addition, the finite impulse response filters employed here compensate the round trip delays as well as smooth transmission rate. Further, we draw a sufficient condition for system stability and analyze the robustness margin along with the maximum tolerable delay from frequency domain technique. With lag compensators satisfactory steady state performance and scalable robustness can be achieved. Also, we expound the choices of parameters from robustness point of view, which has been related with fairness. Through simulations, the effectiveness of the proposed algorithm is shown as compared with the LQG algorithm. [ABSTRACT FROM AUTHOR]

The ability to process optical signals without passing into the electrical domain has always attracted the attention of the research community. Processing photons by photons unfolds new scenarios, in principle allowing for unseen signal processing and computing capabilities. Optical computation can be seen as a large scientific field in which researchers operate, trying to find solutions to their specific needs by different approaches; although the challenges can be substantially different, they are typically addressed using knowledge and technological platforms that are shared across the whole field. This significant know-how can also benefit other scientific communities, providing lateral solutions to their problems, as well as leading to novel applications. The aim of this Roadmap is to provide a broad view of the state-of-the-art in this lively scientific research field and to discuss the advances required to tackle emerging challenges, thanks to contributions authored by experts affiliated to both academic institutions and high-tech industries. The Roadmap is organized so as to put side by side contributions on different aspects of optical processing, aiming to enhance the cross-contamination of ideas between scientists working in three different fields of photonics: optical gates and logical units, high bit-rate signal processing and optical quantum computing. The ultimate intent of this paper is to provide guidance for young scientists as well as providing research-funding institutions and stake holders with a comprehensive overview of perspectives and opportunities offered by this research field. [ABSTRACT FROM AUTHOR]

The study on the dynamics of interacting diseases has attracted considerable attention in recent years. This paper proposes a model for two interacting epidemics spreading concurrently on a two-layer network, where both the epidemic thresholds and the dynamics of disease outbreaks are investigated. The analytical expression of the epidemic threshold shows strong coupling between the two interacting epidemics. Moreover, two metrics, the maximum prevalence and the highest spreading speed, are proposed to describe the outbreak process. Theoretical analysis together with extensive simulations illustrate the functions of various factors, including the network topological parameters, percentage of overlapped network links, vulnerable individuals, and the reciprocity of the two diseases. It is found that the seemingly important factor, i.e., the percentage of overlapped links, possesses no effect on the propagation, while the frequently overlooked factor, i.e., the percentage of vulnerable individuals, has significant effects. For the interaction of the two diseases, the recovery state of one disease is more influential than the other in both the mutually enhanced and the mutually impaired situations. [ABSTRACT FROM AUTHOR]