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The acid-base characteristics of naturally occurring illites, collected from different locations, were investigated by potentiometric titrations. The experimental data were interpreted using the constant capacitance surface complexation model. Considerable release of Al and Si from illite samples and subsequent complexation or precipitation of hydroxyl aluminosilicates generated during the acidimetric forward titration and the alkalimetric back titration, respectively, were observed. Therefore, the acidimetric supernatant, rather than the neutral one, was regarded as the system blank for each illite suspension to yield the surface site concentrations. In order to describe the acid-base chemistry of aqueous illite surfaces, two surface proton-reaction models, introducing the corresponding reactions between the dissolved aluminum species and silicic acid, as well as a surface Al-Si complex on homogeneous illite surface sites, were proposed as follows: The K(f2) constant in Model II was obtained by simulating the complex formation between the dissolved aluminum species and silicic acid that occurred in acidimetric supernatant when the hydroxide was added. Additionally, the following cation exchange reaction was also considered for a special case, where a large amount of K(+) is released during the corresponding acidimetric titration, in which a high concentration of protons are consumed. Optimization results indicated that both models could provide a good description of the titration behavior for all aqueous illite systems in this study. The intrinsic acidity constants for the different illites were similar in Model I, showing some generalities in their acid-base properties. Model I may be considered as a simplification of Model II, evident in the similarities between the corresponding constants. In addition, the formation constant for surface Al-Si species (complexes or precipitates) is relatively stable in this study. Copyright 1999 Academic Press.

An equilibrium partitioning approach was employed to develop preliminary sediment quality criteria (SQC) for heavy metals in surficial sediments of the Le An River, near the large Dexing copper mine. Acid-volatile sulfide and interstitial water criteria toxic units for single and multiple metals were derived in this study. After comparison, the results indicated that, within different sections of the river, violation of corresponding SQC by current concentrations of copper, lead and zinc occurred to varying extents. This situation is probably attributable to the discharges of acidic drainage carrying a large amount of copper originating from Dexing copper mine, and to wastewaters containing high levels of zinc and lead released from numerous small smelters and panning activities along the banks of the river. The acidity of effluents from mining activities, and the excessive concentrations of multiple metals, particularly copper in the sediments, made dominant contributions to the severe degradation of local benthic ecosystems. These conclusions are in accordance with an assessment made using the integrative sediment quality triad. Based on combined evidence from different approaches, therefore, control at the contaminant sources is urgently required. (C) 1999 Elsevier Science Ltd. All rights reserved.

By integrating data on the chemistry, toxicity and benthic community structure, the sediment quality triad was used to evaluate the current situation of superficial sediments from the Le An River. This river has been strongly polluted with large amounts of copper, lead and zinc in waste water discharging from riparian mining and smelting activities. The response of the benthic environment was illustrated by ratio-to-reference (RTR) scale in corresponding triaxial graph. From upstream to downstream, the response intensity of three components showed sectional characteristics. The upstream area was relatively clean due to less disturbance. Within the middle stream area, extreme toxicity and serious deterioration of the benthic community structure could be mainly ascribed to strong acidity in drainage and high concentrations of multiple metals in superficial sediments, especially copper. Because of the river self-purification capability, pollution gradually declined and the sediment quality began to recover downstream. The situation was closely associated to the distribution of major pollution sources, therefore, source control and dredging operation on contaminated sediments in the middle stream area are required urgently.

A Fourier transform infrared spectrometer was employed to determine automatically the total inorganic carbonate (TIC) in solids and waters, based on active photoacoustic absorption of infrared light by carbon dioxide. A 2.0 l reactor, connected to the spectrometer, is immersed in water-bath at 20 °C. After purging with pure N2, 5 ml of 0.5 mol l–1 HClO4 are injected into 50 ml of solid suspension or solution with continuous stirring. The specific absorption of infrared light by the CO2 evolved induces corresponding fluctuations of temperature and pressure in a measurement chamber. Accordingly, photoacoustic signals, with frequencies dependent on the absorbed wavelengths, are generated and measured by the chamber microphones in the form of an absorption spectrum and concentration. For solids, the method exhibits a linear response up to 120 mg of CaCO3 with a detection limit of 0.02 mg; in the case of waters, these figures of merit are 36.4 mmol l–1 and 3 µmol l–1 NaHCO3, respectively. Since proton consumption by TIC in clay minerals may commonly influence the evaluation of surface acid–base properties, the methodology was applied to determine TIC in three natural illite samples of different origins. In addition, some potential interferences and modifications of this method are discussed.

An overmoded photonic crystal resonant cavity with two dimensional dielectric lattice structures is proposed and simulated. The dominant mode is a higher-order TM03-like at the frequency of 31.14GHz, the fundamental mode and most other modes are not supported by the cavity. The structure would be potential for application in accelerator, gyrotron and klystron in Ka-band. DOI: 10.2529/PIERS061007043414

For the researches of input structure of confocal quasi-cylindrical gyrotron amplifier with frequency at 220GHz, the parameters of input structure are optimum with a help of CST studio. The input structure including WR4 waveguide, WR2.8 waveguide, 90° circle waveguide and confocal quasi-cylindrical waveguide are studied. The results show that the TE06 mode is obtained in confocal quasi-cylindrical waveguide with the optimum structure.

The present study examined deposition fluxes of aerosol particles and 15 polycyclic aromatic hydrocarbons (PAHs) associated with the particles in the North China Plain. The annual mean deposition fluxes of aerosol particles and 15 PAHs were 0.69 ± 0.46 g/(m(2) ×d) and 8.5 ± 6.2 μg/(m(2) ×d), respectively. Phenanthrene, fluoranthene, pyrene, chrysene, benzo[b]fluoranthene, and benzo[k]fluoranthene were the dominant PAHs bound to deposited aerosol particles throughout the year. The total concentration of 15 PAHs in the deposited aerosol particles was the highest in winter but lowest in spring. The highest PAH concentration in the deposited aerosol particles in winter was because the heating processes highly increased the concentration in atmospheric aerosol particles. Low temperature and weak sunshine in winter reduced the degradation rate of deposited aerosol particle-bound PAHs, especially for those with low molecular weight. The lowest PAH concentration in deposited aerosol particles in spring resulted from the frequently occurring dust storms, which diluted PAH concentrations. The mean deposition flux of PAHs with aerosol particles in winter (16 μg/[m(2) ×d]) reached 3 times to 5 times that in other seasons (3.5-5.0 μg/[m(2) ×d]). The spatial variation of the deposition flux of PAHs with high molecular weight (e.g., benzo[a]pyrene) was consistent with their concentrations in the atmospheric aerosol particles, whereas such a phenomenon was not observed for those with low molecular weight (e.g., phenanthrene) because of their distinct hydrophobicity, Henry's law constant, and the spatially heterogeneous meteorological conditions.

The building thermal capacity can be used for shifting on-peak load and reducing peak cooling/heating in commercial and residential buildings. The optimization of the pre-cooling/pre-heating is a complicated problem of several major factors, including utility rates, load profiles, building storage characteristics and weather conditions. This paper introduces an intelligent search algorithm, Particle Swarm Optimization (PSO), to find the near optimal solution. A simulation model of a single floor with multi-zone based on a real lab building in Carnegie Mellon University is built with Energyplus to simulate the proposed algorithm. By using MLE+, the EnergyPlus model of the building becomes an S-function block in the Matlab/Simulink, and all available Matlab toolboxes can be used for control and optimization purposes. Simulation results demonstrate the feasibility and the effectiveness of the proposed method.

QTL mapping in multiple families identifies trait-specific and pleiotropic QTL for biomass yield and plant height in triticale. Triticale shows a broad genetic variation for biomass yield which is of interest for a range of purposes, including bioenergy. Plant height is a major contributor to biomass yield and in this study, we investigated the genetic architecture underlying biomass yield and plant height by multiple-line cross QTL mapping. We employed 647 doubled haploid lines from four mapping populations that have been evaluated in four environments and genotyped with 1710 DArT markers. Twelve QTL were identified for plant height and nine for biomass yield which cross-validated explained 59.6 and 38.2 % of the genotypic variance, respectively. A major QTL for both traits was identified on chromosome 5R which likely corresponds to the dominant dwarfing gene Ddw1. In addition, we detected epistatic QTL for plant height and biomass yield which, however, contributed only little to the genetic architecture of the traits. In conclusion, our results demonstrate the potential of genomic approaches for a knowledge-based improvement of biomass yield in triticale.

Daily dietary and inhalation exposures to 16 parent polycyclic aromatic hydrocarbons (PAHs) and urinary excretion of 13 monohydroxy metabolites (OHPAHs) were monitored for 12 non-smoking university students in Beijing, China, during a controlled feeding experiment. The relationship between the urinary excretion of OHPAHs and the uptake of PAHs was investigated. The results suggest severe exposure of the subjects to PAHs via both dietary and inhalation pathways. Large increase of most urinary OHPAHs occurred after the ingestion of lamb kabob. Higher concentrations of OHPAHs were observed for female subjects, with the intakes of parent PAHs lower than those by males, likely due to the gender differences in metabolism. It appears that besides 1-PYR, metabolites of PHE could also be used as biomarkers to indicate the short-term dietary exposure to PAHs and urinary 3-BaA may serve as the biomarker for inhalation intake of high molecular weight PAHs.

The Development of the 10MW L-band multibeam klystron was started in the Institute of Electronics, Chinese Academy of Sciences (IECAS) three years ago. The electrical and structural designs for this klystron have been accomplished , in which many technical problems have been resolved. In the design of electron optical system, the uniform field multiple-lens focusing scheme was adopted, by which the paraxial multi-beams with good laminarity and fluctuation were obtained. In the design of beam-wave interaction system, the second harmonic cavity was used to enhance the beam-wave interaction efficiency and reduce the volume and weight of the klystron. Nowadays, the prototype is being fabricated and will be finished in one or two months. This paper presents the research progress on the 10MW L-band multi-beam klystron and the key technical issues resolved in detail.

In this paper, a novel terahertz (THz) extended interaction oscillator (EIO) is presented. Adopting PIC code , design and optimization geometry of EIO is performed, which is composed of ladder loaded rectangular waveguide. In present work, the operation center frequency of THz EIO is 105GHz , and the output power 673W is achieved, the efficiency reaches 12.1%, which is beam voltage and beam current is 14 kV and 0.4A , respectively.

Escherichia coli-associated diarrhoea is an important disease adversely affecting the pig industry. This study was conducted to investigate the frequency of virulence factors expressed by E. coli strains isolated from suckling pigs with diarrhoea in China. A total of 381 E. coli strains, obtained from 290 faecal samples from pigs on 38 farms, were tested for fimbriae (K88, K99, 987P, F41, F18, F17), non-fimbrial adhesins (AIDA-I, paa, CS31A, eae, saa), enterotoxin (LT-I, LT-II, STa, STb, EAST1), Shiga toxin (Stx1, Stx2, Stx2e), pathogenicity islands (HPI, LEE), α-haemolysin (hlyA), afa8 gene cluster (afaD, afaE) and sepA genes by PCR. Out of the 381 isolates, 206 carried at least one virulence gene. Of the 206 virulence positive isolates, the virulence factor genes detected were EAST1 (n=120), irp2 (n=59), paa (n=50), STb (n=41), AIDA-I (n=34), LT-I (n=23), ler (n=11), hlyA (n=9), K88 (n=8), eae (n=8), STa (n=7), sepA (n=6), F18 (n=5), afaD (n=3), afaE (n=3), K99 (n=2) and Stx2e (n=1), with most isolates carrying multiple virulence genes. These results demonstrate that relatively few isolates from the study population express K88, K99, LT-I or STa, but that EAST1 (58%), irp2 (29%), AIDA-I (16.5%), paa (24%) and STb (20%) are frequent virulence factors expressed by E. coli strains isolated from suckling pigs with diarrhoea in China.

The plasma-surface interactions expected in the divertor of a future fusion reactor are characterized by extreme heat and particle fluxes interacting with the plasma-facing surfaces. Powerful linear plasma generators are used to reproduce the expected plasma conditions and allow plasma-surface interactions studies under those very harsh conditions. While the ion energies on the divertor surfaces of a fusion device are comparable to those used in various plasma-assited deposition and etching techniques, the ion (and energy) fluxes are up to four orders of magnitude higher. This large upscale in particle flux maintains the surface under highly non-equilibrium conditions and bring new effects to light, some of which will be described in this paper.

In this paper, a three-dimensional dielectric loaded grating (DLG) is proposed for the Smith-Purcell (SP) device. Taking into the considerations of thickness and width of electron beam, the dispersion equation is derived by using field matches method. The complex frequency is obtained by the numerical solution of dispersion equation, in which the imaginary part represents linear growth rate. The impacts of the electron beam filling factor (EBFF) on growth rate are discussed under the condition that the beam current and beam current density are kept as constants, respectively. In addition, the start current for SP oscillator is obtained by using the dispersion relation combined with boundary conditions. The relationship between the start current and other parameters is discussed and compared with the conventional metal grating. The results show that with the increasing of EBFF, the peak growth rate increases rapidly firstly and then decreases slowly, in which the current and current density are kept as constants, respectively. For the SP oscillator, the start current is increased with the shifting up beam voltage, but it is decreased with the improved EBFF, and only it has a slightly increasing trend when EBFF is close to 1. In addition, the start current is decreased with the increasing of relative dielectric constant, which indicates that by introducing DLG, the start current can be effectively reduced. Theoretical results are in good agreement with that of the simulations.

Finite element modeling analysis has been employed to simulate the melt layer motion of tungsten and tungsten-based materials under high magnetic field. High heat flux of 2 GW m−2 was loaded for 3 ms at 1000 K and provided a molten bath. Meanwhile, high magnetic field from 0 to 8 T was loaded during the simulation. Both positive and negative surface tension temperature coefficient was tested. The result shows that the convention forced by the surface tension is suppressed by the magnetic field. The high magnetic field performs as a resistance of the heat transfer, leading to a reduced molten bath. The magnetic field mitigates the melting behaviur of the tungsten materials.

The introduction of fast-response battery energy storage system (BESS) provides a number of advantages to address the new challenges of smart grids, including improving the reliability and security of the power grids. This paper proposes a real-time distributed control algorithm to the corrective security-constrained DC optimal power flow problem for transmission network. The objective is to minimize the adjustment of the BESSs, while maintaining the supply-demand balance and ensuring no security constraint violations in the post-contingency state for the short-term period. Comparing to the conventional centralized methods, only simple local computation and information exchange with neighbors are required to update the local control signal, which leads to fast response of the BESSs to alleviate the impact of the transmission line outage. Real-time simulation results of the modified 6-bus and 24-bus systems demonstrate that the dynamic performances of proposed distributed algorithm satisfy standard requirements and indicate its applicability for practical power grid.

The extended interaction oscillator (EIO) is considered to be a novel type of high power terahertz (THz) source, which has promising application prospects in radar, medical imaging etc. Up to now, CPI and other institutes have developed many types of EIO. Currently the G-band EIO is being developed at the Institute of Electronics, Chinese Academy of Sciences (IECAS). The electric and structural designs for the EIO have been accomplished, in which many technical problems are continued to be resolved. The design of electron optics system for EIO has been finished and the permanent magnetic field is adopted. This paper presents mainly the design of electron optics system for the G-band EIO in detail.

Extended Interaction Oscillator (EIO) is a promising Terahertz (THz) high power source, which has many important applications, such as military radar, medical imaging and material science research, etc. For the design being consistent with manufacture, the compact structure of folded waveguide is used for 0.225THz EIO high frequency structure. Moreover, for improvements of operation performance, a novel type of two-section folded waveguide high frequency structure is presented. In this paper, the optimizations of folded structure are conducted by three-dimensional particle-in-cell (PIC) simulation. Up to now, the novel structure has been manufactured and cold test experiment is being prepared.

In this paper, a novel sub-terahertz (THz) extended interaction klystron (EIK) is presented. With the help of a three-dimensional (3D) particle-in-cell (PIC) simulation, design and optimize geometry of THz EIK is performed, which is composed of ladder loaded rectangular waveguide. In present work, the operation center frequency of THz EIK is 94.5GHz, and the CW out power 524W is achieved, the efficiency and bandwidth reaches 4.7% and 230MHz, with gain of 41dB, which is operating at voltage and beam current is 16 kV and 0.6A, respectively.

A novel method for generating superradiant Terahertz (THz) Smith-Purcell (SP) radiation from a two-section gating is presented in this paper. For analyzing the characteristics of this kind of grating, the three-dimensional (3D) particle-in-cell simulations are employed, the time of start oscillator, saturated power, the electric fields near the two-section grating are analyzed with the help of three-dimensional PIC simulation. On the other hand, the radiation power generated from the two-sections grating and normal one is compared. The results of PIC simulations show that the radiation power can be remarkably enhanced and the time of start oscillation can be reduced by the two-sections grating.

In this paper, a novel sub-terahertz (THz) extended interaction oscillator (EIO) is presented. With the help of a three-dimensional (3D) particle-in-cell (PIC) simulation, design and optimize geometry of THz EIO is performed, which is composed of ladder loaded rectangular waveguide. In present work, the operation center frequency of THz EIO is 95GHz, and the out power 2.0kW is achieved, the efficiency reaches 20.8%, which is operating at voltage and beam current is 16 kV and 0.6A, respectively.

Black carbon (BC) emissions from China are of global concern. A new BC emission inventory (PKU-BC(China)) has been developed with the following improvements: (1) The emission factor database was updated; (2) a 0.1° × 0.1° gridded map was produced for 2007 based on county-level proxies; (3) time trends were derived for 1949-2007 and predicted for 2008-2050; and (4) the uncertainties associated with the inventory were quantified. It was estimated that 1957 Gg of BC were emitted in China in 2007, which is greater than previously reported. Residential coal combustion was the largest source, followed by residential biofuel burning, coke production, diesel vehicles, and brick kilns. By using a county-level disaggregation method, spatial bias in province-level disaggregation, mainly due to uneven per capita emissions within provinces, was reduced by 42.5%. Emissions increased steadily since 1949 until leveling off in the mid-1990s, due to a series of technological advances and to socioeconomic progress. BC emissions in China in 2050 are predicted to be 920-2183 Gg/yr under various scenarios; and the industrial and transportation sectors stand to benefit the most from technological improvements.

This research addresses a new cross-training policy to increase labors' job satisfaction and decrease tasks' labor cost. The cross-training plan is about how to decide which labors should be cross-trained on which tasks. A multiobjective 0–1 integer programming model is formulated for the cross-training policy. The first objective seeks to maximize average satisfaction degree (ASD), and the second objective seeks to minimize average paid salary (APS). The mathematical model is solved with particle swarm optimization algorithm (PSO). And a series of computational experiments are proceeded to analyze the factors impacting on the performance of the cross-training plan. The results indicate that with regards to ASD, the balanced preference structure is better than the extreme one, and with regards to APS, the nonuniform salary structure is better than the uniform one. Those insights will help practioners to make correct decisions.

In China, the R&D of high peak power klystron has been made much progress in recent years. In 2010, the Institute of Electronics, Chinese Academy of Sciences (IECAS) has successfully developed S-band 100MW klystron, and, currently, are developing an S-band 150MW klystron. The Institute of High Energy Physics, Chinese Academy of Sciences (IHEP) cooperated with the Hang Guang Electrical Factory has developed S-band 65MW klystron. In this paper, the specifications of our typical high peak power klystrons are presented and the key technical problems for developing this kind of klystron will be discussed in this conference.

The objective of this study was to establish a loop-mediated isothermal amplification (LAMP) method for the detection of F5 fimbriae gene in Enterotoxigenic Escherichia coli. A set of four primers were designed based on the conservative sequence of coding F5 fimbriae. Temperature and time condition, specificity test, and sensitivity test were performed with the DNA of Escherichia coli (F5+). The results showed that the optimal reaction condition for LAMP was achieved at 61 °C for 45 min in a water bath. Ladder-like products were produced with those F5-positive samples by LAMP, while no product was generated with other negative samples. The assay of LAMP had a detection limit equivalent to 72 cfu/tube, which was more sensitive than PCR (7.2 × 10(2) cfu/tube). The agreement rate between LAMP and PCR was 100 % in detecting simulation samples. Thus, the LAMP assay may be a new method for rapid detection of F5 fimbriae gene of ETEC.

Detection of QTL in multiple segregating populations is of high interest as it includes more alleles than mapping in a single biparental population. In addition, such populations are routinely generated in applied plant breeding programs and can thus be used to identify QTL which are of direct relevance for a marker-assisted improvement of elite germplasm. Multiple-line cross QTL mapping and joint linkage association mapping were used for QTL detection. We empirically compared these two different biometrical approaches with regard to QTL detection for important agronomic traits in nine segregating populations of elite rapeseed lines. The plants were intensively phenotyped in multi-location field trials and genotyped with 253 SNP markers. Both approaches detected several additive QTL for diverse traits, including flowering time, plant height, protein content, oil content, glucosinolate content, and grain yield. In addition, we identified one epistatic QTL for flowering time. Consequently, both approaches appear suited for QTL detection in multiple segregating populations.

This paper summarizes ongoing research in the application of intelligent methods to the design, modeling, simulation and control of microgrids including optimal design of microgrids, and centralized and decentralized control.

Genomic selection is a promising breeding strategy for rapid improvement of complex traits. The objective of our study was to investigate the prediction accuracy of genomic breeding values through cross validation. The study was based on experimental data of six segregating populations from a half-diallel mating design with 788 testcross progenies from an elite maize breeding program. The plants were intensively phenotyped in multi-location field trials and fingerprinted with 960 SNP markers. We used random regression best linear unbiased prediction in combination with fivefold cross validation. The prediction accuracy across populations was higher for grain moisture (0.90) than for grain yield (0.58). The accuracy of genomic selection realized for grain yield corresponds to the precision of phenotyping at unreplicated field trials in 3–4 locations. As for maize up to three generations are feasible per year, selection gain per unit time is high and, consequently, genomic selection holds great promise for maize breeding programs.

In this paper, a two-section folded waveguide of Terahertz (THz) extended interaction oscillator (EIO) is presented, which is studied by the help of particle-in-cell (PIC) simulation. The output power and operation frequency are studied.

Association mapping (AM) is a powerful approach to dissect the genetic architecture of quantitative traits. The main goal of our study was to empirically compare several statistical methods of AM using data of an elite maize breeding program with respect to QTL detection power and possibility to correct for population stratification. These models were based on the inclusion of cofactors (Model A), cofactors and population effect (Model B), and SNP effects nested within populations (Model C). A total of 930 testcross progenies of an elite maize breeding population were field-evaluated for grain yield and grain moisture in multi-location trials and fingerprinted with 425 SNP markers. For grain yield, population stratification was effectively controlled by Model A. For grain moisture with a high ratio of variance among versus within populations, Model B should be applied in order to avoid potential false positives. Model C revealed large differences among allele substitution effects for trait-associated SNPs across multiple plant breeding populations. This heterogeneous SNP allele substitution effects have a severe impact for genomic selection studies, where SNP effects are often assumed to be independent of the genetic background.

Overload indicator (OI) and high interference indicator (HII) are two main approaches to mitigate inter-cell interference in long term evolution (LTE) system. Using OI or HII separately will incur inevitable shortcomings, therefore, in this paper, an OI&HII hybrid scheme is proposed for inter-cell interference coordination (ICIC) through signaling interaction between the two schemes. Instead of broadcasting OI message to all the neighboring cells, in the proposed scheme, the serving base stations (BS) just sends it to selected neighbors to inform them to adjust uplink transmission power. Simulation results show that this new scheme can effectively enhance the uplink throughput while reducing signaling overhead on the X2 interface at the same time.

In this paper, the VHDL implementation of an intelligent navigation system using hybrid fuzzy controllers has been proposed. Two parallel fuzzy logic controllers are utilized to conquer the major mobile robot navigation challenges in narrow concave U-shaped obstacles, and deep narrow passage, and to track a target in an environment with varying obstacles. The results demonstrate the suitability of the FPGAs in control tasks for multiple fuzzy logic controllers. The implementation of the control units for the robot with FPGA is an important approach in the way for building a real prototype. The proposed algorithm involves fuzzy model of robot navigation system and the hybrid controllers are designed and evaluated based on this models. Such a method will further advance the development of a real-world intelligent control system for performance evaluation of various control strategies in a prototype robotic vehicle.

In many manufacturing plants assembly lines(AL) are converted to assembly cells(AC) for satisfying the increasing market demand for shorter product delivery lead times, customization, and just-in-time(JIT) manufacturing in particular. Previous research is focused to compare two kinds of systems with some goals, such as average batch flow time and utilization rates. This research compares a multi-model assembly line (MMAL) and AC with the usage rate of all parts fed into the assembly system as constant as possible in a (JIT) environment, which is called the level-scheduling problem. Firstly, the level scheduling models in each manufacturing system are proposed for computing the performance values. Then, simulation experiments are conducted to compare the performance of MMAL and AC configurations. Operating environments vary by the ratio of product types (models) to product batches. The results indicate that AC is better than MMAL with the larger ratio. The conclusions highlight guidelines for practicing managers on the most appropriate system under a given set of operating conditions.

Epistatic interactions may contribute substantially to the hybrid performance of sugar beet. The main goal of our study was to dissect the genetic basis of eight important physiological and agronomic traits using two different biometrical models for joint linkage association mapping. A total of 197 genotypes of an elite breeding population were evaluated in multi-location trials and fingerprinted with 194 SNP markers. Two different statistical models were used for the genome-wide scan for marker-trait associations: Model A, which corrects for the genetic background with markers as cofactors and Model B, which additionally models a population effect. Based on the extent of linkage disequilibrium in the parental population, we estimated that for a genome-wide scan at least 100 equally spaced markers are necessary. We mapped across the eight traits 39 QTL for Model A and 22 for Model B. Only 11% of the total number of QTL were identified based on Models A and B, which indicates that both models are complementary. Epistasis was detected only for two out of the eight traits, and contributed only to a minor extent to the genotypic variance. This low relevance of epistasis implies that in sugar beet breeding the prediction of performance of three-way hybrids is feasible with high accuracy based on the means of their single crosses.

ISCLT3 dispersion model was applied to calculate the flux of dry deposition of polycyclic aromatic hydrocarbons (PAHs) in Tianjin, China based on a high resolution emission inventory. Field observations of dry deposition at 22 sampling sites were used for model validation. The mean deposition flux densities (and standard deviation) of 15 PAHs were 4.62 +/- 2.99 microg m(-2) d(-1) and 2.75 +/- 1.78 microg m(-2) d(-1) in the heating and the non-heating seasons, respectively, with a time-weighted annual mean of 3.37 +/- 1.81 microg m(-2) d(-1) (based on the durations of the heating and non-heating seasons). High fluxes occurred in the urbanized areas as well as near two coke and gasification facilities. It was revealed that PAH concentrations in surface soil were correlated significantly with both dry deposition and soil organic matter content. Accordingly, a linear regression model was developed for predicting surface soil PAH concentration based on deposition flux density and soil organic matter content.

Evaluation of bit error rate (BER) of digital communication systems is usually done via simulation using Monte Carlo (MC) method. For low BER, MC method requires huge sample sizes to achieve certain efficiency. To overcome this limitation, many variance reduction techniques such as importance sampling (IS) have been proposed. In this paper, a novel simulation method-Monte Carlo simulation with error classification (EC-MC) is discussed. This method can reduce the estimation variance through dividing the total errors into many subcategories and optimizing the simulation sample size for each sub-category. We apply this method for simulations of QAM modulation under Rayleigh fading channel. The simulation results demonstrate EC-MC method can achieve the same accuracy at smaller sample sizes and shorter simulation runtime, comparing with both conventional MC and IS methods, especially at high signal to noise ratios.