Estimation of Geodetic Parameters with VLBI Data of Last 5 Years

The meaning to research the potential of VLBI for geodetic applications is summarized. And the observation models and their related parameters of geodetic interest are investigated. Then, the principle and method of using the random model in VLBI data processing are investigated. With the world wide VLBI data from 2000-2004, the conditions to compute the parameters of geodetic interest are introduced, and so are the computing methods and processes. And the computed resuits of the parameters of geodetic interest are analyzed.

Sensitivity analysis of relevant parameters in complicated mine ventilation network by numerical test

Depending on the numerical test approach on a computer, the relationships among relevant parameters, eg branch number, node number, mesh number, computation accuracy, preliminary value of airflow rate, iteration number, computation time and convergence in a mine ventilation network analysis, were investigated based on 5 mine ventilation systems. The results show that a higher computation accuracy greatly influences the iteration number. When the accuracy reaches 10-6m3·s-1 for solving a complicated mine ventilation network, the running time is too long though a high-speed computer is used. The preliminary value of airflow rate in the range of 1100m3·s-1 has little effects the iteration number. The structure of network also has some effect on the iteration number.

Study of petrophysical parameter sensitivity from well log data

Proper analysis of petrophysical parameter sensitivity from well log data can greatly improve the ability to discriminate hydrocarbon-bearing rocks. In this paper we discuss a petrophysical analysis method for the selection and application of higher sensitivity seismic attribute parameters to improve the ability to discriminate fluid and lithology. To better integrate with seismic interpretation, we construct a template to highlight rock physics parameters in sensitivity space, providing guidance for the quantitative seismic interpretation of hydrocarbon-bearing reservoirs.

Cosmological Constraints on the Sign-Changeable Interactions

Recently, Cai and Su [Phys. Rev. D 81 （2010） 103514] found that the sign of interaction Q in＇the dark sector changed in the approximate redshift range of 0.45 ≤ z ≤0.9, by using a modeMndependent method to deal with the observational data. In fact, this result raises a remarkable problem, since most of the familiar interactions cannot change their signs in the whole cosmic history. Motivated by the work of Cai and Su, we have proposed a new type of interaction in a previous work [H. Wei, Nucl. Phys. B 845 （2011） 381]. The key ingredient is the deceleration parameter q in the interaction Q, and hence the interaction Q can change its sign when our universe changes from deceleration （q 〉0） to acceleration （q 〈 0）. In the present work, we consider the cosmologicai constraints on this new type of sign-changeable interactions, by using the latest observational data. We find that the cosmological constraints on the model parameters are fairly tight. In particular, the key parameter β can be constrained to a narrow range.

Selection of Measured Signals in the Navigation Measuring Complex

To increase accuracy of navigation parameters,a perspective measuring complex with intellectual components is developed.Conception of synthesis optimal structure of the measuring complex is realized basing on a selective method using principles of the functional systems.Selection of measured information is finished by original numeric criterion of observation level of state vector components.Prediction is realized by algorithm of self-organization that makes synthesis of the optimal complication.Therefore mechanism of self-regulation is realized and accuracy of the selective navigation complex is increased.

Determination of photosynthetic parameters in two seawater-tolerant vegetables

It is difficult to determine the photosynthetic parameters of non-fiat leaves/green stems using photosynthetic instruments, due to the unusual morphology of both organs, especially for Suaeda salsa and Salicornia bigelovii as two seawater-tolerant vegetables. To solve the problem, we developed a simple, practical, and effective method to measure and calculate the photosynthetic parameters （such as PN, gs, E） based on unit fresh mass, instead of leaf area. The light/COftemperature response curves of the plants can also be measured by this method. This new method is more effective, stable, and reliable than conventional methods for plants with non-flat leaves. In addition, the relative notes on measurements and calculation of photosynthetic parameters were discussed in this paper. This method solves technical difficulties in photosynthetic parameter determination of the two seawater-tolerant vegetables and similar plants.

New processing method for fire forecast parameters

The time forecast system of coal spontaneous combustion was described based on the KJ-90 mine environmental monitoring system in Hulipo Mine, Luzhou, Sichuan Province. In the system, CO and O2 sensor are added, and special-purpose microcomputer and software are equipped. By means of the system, the fluctuation laws of fire forecast parameters were observed in the process of coal-cutting, blast, exogenous mine fire and working face air quantity variation. This paper puts forward data processing method based on the Raita method.

Numerical and experimental evaluation on methods for parameter identification of thermal response tests

Several parameter identification methods of thermal response test were evaluated through numerical and experimental study.A three-dimensional finite-volume numerical model was established under the assumption that the soil thermal conductivity had been known in the simulation of thermal response test.The thermal response curve was firstly obtained through numerical calculation.Then,the accuracy of the numerical model was verified with measured data obtained through a thermal response test.Based on the numerical and experimental thermal response curves,the thermal conductivity of the soil was calculated by different parameter identification methods.The calculated results were compared with the assumed value and then the accuracy of these methods was evaluated.Furthermore,the effects of test time,variable data quality,borehole radius,initial ground temperature,and heat injection rate were analyzed.The results show that the method based on cylinder-source model has a low precision and the identified thermal conductivity decreases with an increase in borehole radius.For parameter estimation,the measuring accuracy of the initial temperature of the deep ground soil has greater effect on identified thermal conductivity.

Hazardous Events on the Black Sea Rivers, Their dynamics and Regulation

The historical, informational and literary sources regarding flooding have been studied. Based on the statistical processing of multiyear stationary observation data the river maximal discharge parameters are specified. According tendency of their dynamics the flooding strengthening has been revealed on rivers nourished by glaciers, on the contrary in other rivers they reduced, in some regions evaporation has been increased and desertifieation has been detected. For mitigation negative impacts of those processes the recommendations of prevention measures are drafted.

Microphysical Structure of a Nimbostratus over Jilin Province Provided by Airborne Observations

Airborne measurements were collected during a stepwise ascent within a nimbostratus cloud associated with a cold vortex depression over the Jilin Province on 21 June 2005 to study cloud structure and ice particle spectra. The melting layer of the nimbostratus was clearly defined in the radar images. The microphysical structure of the nimbostratus was elucidated by a King liquid water probe and Particle Measuring Systems （PMS） probes aboard the research aircraft. The PMS 2-D images provided detailed information of ice crystal transformations. A thick layer of supercooled cloud was observed, and the high ice particle concentrations at temperatures ranging from -3℃ to -6℃ were consistent with Hallett-Mossop ice multiplication. The shape of ice crystals from near the cloud top to the melting layer were in the form of columns, needles, aggregations, and plates. In addition, significant horizontal variability was evident on the scale of few hundred meters. Particle spectra in this cloud were adequately described by exponential relationships. Relationship between the intercept （No） and slope （2） parameters of an exponential size distribution was well characterized by a power law.

Correlates of subjectively and objectively measured physical activity in young adolescents

Background： Many studies examining individual-level correlates in youth utilize self-report rather than objective measures of physical activity （PA）. This utilization of self-report may result in associations that are not present when examining objectively measured PA. The present study investigates the relationship between hypothesized correlates of PA with objectively and subjectively measured PA. Methods： Participating children （n 232, 101 males, mean age - 12.3 years） provided a minimum of four monitored days of PA （via accelerometer） and completed a survey assessing moderate-to-vigorous physical activity （MVPA）, sport competence, appearance, enjoyment, and self-efficacy. Height and weight were measured and body mass index （BMI） was calculated. Results： Hierarchical regression models controlling for sex, race, and BMI Z-score showed that only sex and BMI Z-score were significant correlates of objective MVPA while only sex was a significant correlate of objective total PA. However, in a separate model examining the relationship with subjective MVPA, enjoyment of PA and self-efficacy for PA were the only significant correlates of self-reported PA. Conclusion： Measuring MVPA via self-report versus accelerometry produces considerably different results in a sample of young adolescents. Future studies should use caution when selecting outcome measures if the intent is to identify modifiable correlates of MVPA in youth.

An efficient approach for shadow detection based on Gaussian mixture model

An efficient approach was proposed for discriminating shadows from moving objects. In the background subtraction stage, moving objects were extracted. Then, the initial classification for moving shadow pixels and foreground object pixels was performed by using color invariant features. In the shadow model learning stage, instead of a single Gaussian distribution, it was assumed that the density function computed on the values of chromaticity difference or bright difference, can be modeled as a mixture of Gaussian consisting of two density functions. Meanwhile, the Gaussian parameter estimation was performed by using EM algorithm. The estimates were used to obtain shadow mask according to two constraints. Finally, experiments were carried out. The visual experiment results confirm the effectiveness of proposed method. Quantitative results in terms of the shadow detection rate and the shadow discrimination rate(the maximum values are 85.79% and 97.56%, respectively) show that the proposed approach achieves a satisfying result with post-processing step.

The integrated monitoring system for running parameters of key mining equipment based on condition monitoring technology

An integrated monitoring system for running parameters of key mining equipmenton the basis of condition monitoring technology and modern communication networktechnology was developed.The system consists of a client computer with functions ofsignal acquisition and processing, and a host computer in the central control room.Thesignal acquisition module of the client computer can collect the running parameters fromvarious monitoring terminals in real-time.The DSP high-speed data processing system ofthe main control module can quickly achieve the numerical calculation for the collectedsignal.The signal modulation and signal demodulation are completed by the frequencyshift keying circuit and phase-locked loop frequency circuit, respectively.Finally, the signalis sent to the host computer for logic estimation and diagnostic analysis using the networkcommunication technology, which is helpful for technicians and managers to control therunning state of equipment.

Calculation of maximum surface settlement induced by EPB shield tunnelling and introducing most effective parameter

This study aims to predict ground surface settlement due to shallow tunneling and introduce the most affecting parameters on this phenomenon.Based on data collected from Shanghai LRT Line 2 project undertaken by TBM-EPB method,this research has considered the tunnel's geometric,strength,and operational factors as the dependent variables.At first,multiple regression(MR) method was used to propose equations based on various parameters.The results indicated the dependency of surface settlement on many parameters so that the interactions among different parameters make it impossible to use MR method as it leads to equations of poor accuracy.As such,adaptive neuro-fuzzy inference system(ANFIS),was used to evaluate its capabilities in terms of predicting surface settlement.Among generated ANFIS models,the model with all input parameters considered produced the best prediction,so as its associated R^2 in the test phase was obtained to be 0.957.The equations and models in which operational factors were taken into consideration gave better prediction results indicating larger relative effect of such factors.For sensitivity analysis of ANFIS model,cosine amplitude method(CAM) was employed; among other dependent variables,fill factor of grouting(n) and grouting pressure(P) were identified as the most affecting parameters.

Effects of wind input and wave dissipation formulations on the steady Ekman current solution

The effects of different wind input and wave dissipation formulations on the steady Ekman current solution are described. Two formulations are considered: one from the wave modeling(WAM) program proposed by Hasselmann and Komen and the other provided by Tsagareli and Babanin. The solution adopted for our study was presented by Song for the wave-modifi ed Ekman current model that included the Stokes drift, wind input, and wave dissipation with eddy viscosity increasing linearly with depth. Using the Combi spectrum with tail effects, the solutions are calculated using two formulations for wind input and wave dissipation, and compared. Differences in the results are not negligible. Furthermore, the solution presented by Song and Xu for the eddy viscosity formulated using the K-Profi le Parameterization scheme under wind input and wave dissipation given by Tsagareli and Babanin is compared with that obtained for a depth-dependent eddy viscosity. The solutions are further compared with the available well-known observational data. The result indicates that the Tsagareli and Babanin scheme is more suitable for use in the model when capillary waves are included, and the solution calculated using the K-Profi le Parameterization scheme agrees best with observations.

Determination of design parameter for three-product heavy-medium cyclone

Analyzed the selected raw coal nature and forecasted the number quality of its separated product. Considering each product＇s density, volume, and suspending liquid assignment, combining the separating mechanism of the cyclone and the rela- tive formulas obtained from scientific experimentation and practice, the structure parameter was determined by calculation. This provides a more scientific reasonable method for determining the structure parameter of the unpressurized feeding three-product heavy-medium cyclone.

Method to determine parameters in the rainstorm intensity formula

This paper presents a new method to determine parameters in the nonlinear mathematical model of the urban rainfall intensity formula. The method transforms the nonlinear equation into a linear one, and incorperates a damping factor and a step factor to improve the precision of the calculated results. It works out the parameters based on given rainstorm intensity, period of the recurrence of rainstorm and lasting time of the rainfall. The results turns out to have the smallest residual error compared with those obtained by several other methods and satisfy the related standard. The method proves of fast convergence, desirable generality, stability and accuracy, which overcomes the defects of other existing numeral methods.

A New Approach to Estimating the T-Year Return-Period Wave Height

The paper introduces a new approach to estimating the T-year return-period wave height (TRPW), i.e. the wave height expected to occur in T-year, from two sets of observed extreme data and on the basis of the maximum entropy principle. The main points of the approach are as follows. 1) A maximum entropy probability density function (PDF) for the extreme wave height H is derived from a Euler equation subject to some necessary and rational constraints. 2) The parameters in the function are expressed in terms of the mth moment of H. 3) This PDF is convenient to theoretical and practical applications as it is simple and its four parameters are easy to be determined from observed extreme data. An example is given for estimating the TRPW in 50 and 100 years by the present approach and by some currently used methods using observed data at two hydrographic stations.The comparison of the estimated results shows that the present approach is quite similar to the Pearson-Ⅲ and Gumbel methods.

New Approach for Rapid Assessment of Trophic Status of Yellow Sea and East China Sea Using Easy-to-Measure Parameters

To realize potential cost savings in coastal monitoring programs and provide timely advice for marine management, there is an urgent need for efficient evaluation tools based on easily measured variables for the rapid and timely assessment of estuarine and offshore eutrophication. In this study, using parallel factor analysis(PARAFAC), principal component analysis(PCA), and discriminant function analysis(DFA) with the trophic index(TRIX) for reference, we developed an approach for rapidly assessing the eutrophication status of coastal waters using easy-to-measure parameters, including chromophoric dissolved organic matter(CDOM), fluorescence excitation–emission matrices, CDOM UV-Vis absorbance, and other water-quality parameters(turbidity, chlorophyll a, and dissolved oxygen). First, we decomposed CDOM excitation-emission matrices(EEMs) by PARAFAC to identify three components. Then, we applied PCA to simplify the complexity of the relationships between the water-quality parameters. Finally, we used the PCA score values as independent variables in DFA to develop a eutrophication assessment model. The developed model yielded classification accuracy rates of 97.1%, 80.5%, 90.3%, and 89.1% for good, moderate, and poor water qualities, and for the overall data sets, respectively. Our results suggest that these easy-to-measure parameters could be used to develop a simple approach for rapid in-situ assessment and monitoring of the eutrophication of estuarine and offshore areas.