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An iterative hybrid method is proposed for analyzing the electromagnetic (EM) scattering from complex target above rough surface. First, the electric/magnetic current-combined field integral equation (JMCFIE) is formulated to calculate the EM scattering from the complex target combining conductor and multiple dielectric objects. Then, the single integral equation (SIE) method for multiple dielectric objects in the complex target (MSIE) is applied to reduce one-half of the unknowns in dielectric regions, and the hybrid JMCFIE-MSIE method is formulated. Afterward, physical optics (PO) approximation is employed for computing the EM scattering on the rough surface, and the iterative hybrid based on the combination of JMCFIE-MSIE and PO is derived for composite scattering from complex target above rough surface. Furthermore, the multilevel fast multipole algorithm is utilized to accelerate the matrix-vector multiplications in the computation process. The equivalent edge currents method is applied to meliorate the result. Finally, the validation and applicability of the proposed iterative solution are demonstrated by several numerical examples.

The electromagnetic (EM) scattering characteristics of target above coastal environment are complicated due to the simultaneous existence of ground region and sea region. Nevertheless, the actual target possesses both conducting part and dielectric part. Such a composite scattering problem involves multiple media parameters and large amount of unknowns. Hence, aiming at accurately and efficiently calculating the EM scattering from combined conducting and dielectric target above coastal environment, the hybrid SIE-KA method is introduced in which single integral equation (SIE) method is utilized to reduce the number of combined target's unknowns and Kirchhoff approximation (KA) is applied to obtain induced electric and magnetic current on the surface of coastal environment. Moreover, multilevel fast multipole algorithm (MLFMA) is adopted to significantly reduce the computational cost and memory requirement. Several numerical examples demonstrate the accuracy and efficiency of the hybrid method. Finally, the EM scattering characteristics of combined conducting and dielectric target above coastal environment have been studied. The radar cross section (RCS) curves with different category of environment, polarization mode, working frequency, statistic parameters of coastal environment, permittivity of target's dielectric part, target's height and target category have been analyzed in detail to provide some useful conclusions. The approach and results can be broadly applied in remote sensing simulation of coastal environment with combined target.

A new geometrical model of divisional rough surface is established for simulating the surface of mountainous region. The Gaussian spectrum is applied to represent the statistic properties of mountainous surface. The modeling theory of divisional rough surface is introduced. Two modeling methods for constructing the borderline are given. what's more, the iterative physical optics (IPO) is utilized to obtain the monostatic radar cross-section (RCS) of the divisional rough surface. Several unique phenomena and useful conclusions can be obtained, which can be widely used in remote sensing simulations of mountainous region.

This paper proposes a hybrid method for computing electromagnetic scattering from target above composite rough surface of ground and near sea in adjacent region. First, a kind of composite rough su...

In this paper, wideband radar clutter characteristics of composite rough surface are analyzed. Firstly, Gauss spectrum and the modified JONSWAP spectrum are introduced to establish the geometrical model of ground and near sea in adjacent region. Secondly, a facet-based scattering model is utilized to obtain the scattering from composite rough surface. Sub-band synthesis method is applied to calculate the wideband radar clutter amplitude of scattering cells. Finally, the spectrum characteristics of the composite rough surface's clutter are analyzed. The comparison between single environment and composite are given. The influence of grazing angle on clutter characteristic is discussed.

A hybrid method of single integral equation and the electric/magnetic current combined field integral equation (JMCFIE) is proposed, abbreviated as SJMCFIE, for analyzing scattering from composite conductor and dielectric objects. Fitting Green’s function with fast Fourier transform (FG-FFT) is adopted to combine SJMCFIE to lastly formulate SJMCFIE-FG-FFT for reducing computation complexity of resultant matrix-vector multiplications further. Next, scattering from the composite hemisphere is computed to verify SJMCFIE-FG-FFT on memory storage, computation efficiency compared to SJMCFIE-MLFMA. Simultaneously, comparison of FG-FFT and the other FFT-based algorithms being combined with SJMCFIE shows that SJMCFIE-FG-FFT is insensitive to grid spacing, easy implementation, and high accuracy. Besides, SJMCFIE-FG-FFT also can be used for analyzing scattering from the coated structure.

Polyethersulfone (PES) hollow fiber ultrafiltration (UF) membranes were fabricated by the dry/wet-spinning method; hydrophobic PDMS/PES composite membranes which were supported by self-prepared PES hollow fiber UF membranes were prepared for the pervaporation (PV) separation of ethanol from water. Impacts of PES support layer on the PV performances of PDMS/PES composite membranes were studied. Experimental results showed that, while working as a support to PDMS active layer, PES hollow fiber membrane could affect the PV performance of PDMS/PES membranes greatly. Pervaporation performance of the membrane which its PES support layer had bigger porosity and bigger mean pore size was apparently superior to that of the membrane which its PES support layer had smaller porosity and smaller mean pore size. After being treated with ethanol and hexane, PES membrane was dried in air for 20 min before being immersed in PDMS coating solution; the prepared PDMS/PES membrane had the best PV performance with a pe...

A novel composite membrane of cross-linked poly (vinyl alcohol)/hyperbranched polyester (PVA/HBPE) was prepared using glutaraldehyde (GA) as cross-linking agent for the dehydration of ethylene glycol/water (EG/water) mixtures. Hyperbranched polyester (HBPE) used in the preparation of PVA/HBPE membrane was synthesized through a pseudo one-step reaction of molten state 2,2-bis(hydroxymethyl)propionic acid (bis-MPA) and 1,1,1-trimethylol propane (TMP) using p-toluene sulfonic acid (p-TSA) as the catalyst. The branching degree of prepared HBPE was 0.4551 determined by 13C NMR. FTIR, SEM, XRD, DSC, TGA, water contact angle and mechanical properties of PVA/HBPE membranes were measured to investigate the effects of HBPE on membrane structures and properties. PVA/HBPE membrane had a cross-linked structure and exhibited good thermal stability, good hydrophilicity and superior mechanical strength. When HBPE content was above 20 wt.%, HBPE particles formed on the surfaces of membranes and phase separation between PVA and HBPE occurred. With the increasing of HBPE content, feed water content and feed temperature, permeation flux increased significantly and separation factor decreased dramatically. The membrane containing 10 wt.% HBPE exhibited the best PV performance (water flux and separation factor were 43.77 g/(m2 h) and 312 respectively for the 90 wt.% EG solution at 25 °C). The variation of permeation flux via feed temperature followed the Arrhenius relationship and the activation energy values were 12.83 and 39.29 kJ/mol for water and EG, respectively.

A generalized hybrid scheme combining finite element method (FEM) and the method of moments (MoM) accelerated by multilevel fast multipole algorithm (MLFMA) is first presented to investigate scattering from a 3-D dielectric object above a 2-D electrically large dielectric rough surface. The hybrid FEM/ MoM scheme is divided into the FEM region for the object based on Helmholtz's equation and the MOM region for the rough surface based on coupled integral function, which can greatly reduce the computed region. MLFMA is employed to reduce computation complexity of MOM region itself and coupling interaction matrices between MOM region and FEM region. Consequently the iterative solving process can be greatly accelerated. This genralized hybrid FEM/MOM is very suitable for investigating scattering characteristics of composite model composed of a complex material object and electrically large dielectric rough surface. Some examples verify this generalized hybrid FEM/MOM features high efficiency, low storage requirement, high accuracy and generality.

A composite random rough surface model is presented for describing adjacent region between ground and ocean. Monte Carlo method is used to build composite random rough surface, gauss spectral function is used to simulate ground region, and Pierson Moskowitz (PM) spectral function is used to simulate ocean region. Weighted inverse tangent function is presented to smooth adjacent region. The electromagnetic coupling between facet in respective region and facet in adjacent region is considered, an iterative physical optics (IPO) based on the Stratton-Chu integral equations is presented. The curves of bistatic scattering coefficient (BSC) of ground and ocean rough surface on MHz, GHz, and THz waveband are obtained. Electromagnetic scattering characteristics of ground, ocean, and composite random rough surface on THz waveband are compared. The influences of root mean square (RMS) of ground region and wind velocity of ocean region on BSC of horizontal-to-horizontal (HH) polarization on THz waveband are discussed. The numerical results show that influences of these parameters on BSC of composite random rough surface on THz waveband are very complex.

The quality and integrity of clinical trials and associated data are not only derived from accuracy of trial data analyses, but also closely embodied to the authenticity and integrity of those data and data documents as well as the compliant procedures obtaining those data and relevant files in the life cycle of clinical trials. The compliances of good clinical practices and standards suggest the reliability, complete and accuracy of data and data documents, which is constructing the convincible foundation of drug efficacy and safety validated via clinical trials. Therefore, the monitoring and auditing on clinical trials and associated data quality keep eyes on not only verifications of reliability and correctness on the data analytic outcomes, but also validation of science and compliance of the trial management procedure and documentations in the process of data collections.

ICH GCP requires that all information of clinical trial should be recorded, processed, and stored in a way that allows the accurate reporting, interpretation and verification. A trial master file (TMF) contains all paper or electronic records/documentations related to a clinical trial. As a tool of the retrospective analysis, the TMF profile should be able to reproduce the full procedure of the trial completely. As a part of TMF profiles, both the accuracy and completeness of clinical data management documentation are important in data integrity. It is helpful to learn the workflow of clinical data management in different stage of a clinical trial, to understand which documents are essential, and why the documentation of clinical data management is important for data integrity. This paper elaborates how to perform the good documentation practice of clinical data management, and suggests that both the precise and efficient document management and regular quality control may ensure the high quality of clinical data documentation management on the basis of an intensive awareness of the overall process of clinical data management.

A perfect clinical trial must nave a solid study design, strict conduction, complete quality control, non-interference of statistical result, and acceptable risk-benefit ratio. To reach the target, the quality control (QC) should be performed from the study design to conduction, from the analysis to conclusion. We discuss the relationship between data management and biostatistics from the statistical point of view, and emphasize the importance of the statistical concept and methods in the improvement of data quality in clinical data management.

For pharmaceutical industries, clinical data is one of the most valuable deliverables. It is also the basis of analysis, submission, approval, labeling and marketing of a drug product. To ensure the integrity and reliability of clinical data, a scientific standardized quality control (QC) has to be established at each step of a clinical trial. Data validation is conducted to ensure the reasonability and compliance of clinical data by checking data quality before the data is statistically analyzed. This paper focuses on purpose of data validation, creation of data validation plan, rationale of data validation, types of data validation and performance of user acceptance testing on clinical database.

This list of clincal data management documentation is to ensure standardized and adequate archival of trial documents and records in clinical data management, which is applicable to all of phase I-IV clinical trials.

Transmit-array (TA) has advantages such as low profile, easy fabrication, flexible element structure, and multi-function etc. It receives spherical wave and adjust its phases to re-radiate forwards. TA avoids the effect of feed blockage existing in a reflect-array, can realize arbitrarily linear polarization transform well. In this paper two kinds of broadband element of TA with polarization transform are proposed, their properties of phase compensation, polarization transform and transmission efficiency are analyzed and compared

In this article, a three-layer rectangular patch with similar geometry, thin substrates and air gaps, backed by a ground plane is simulated as the element of reflectarray, in order to broaden the bandwidth and to extend the dynamic range of phase compensation. The simulated results show that, besides 700deg dynamic range of reflection phase is approached under the normal incidence, a polarisation transform can be performed for reducing the feed blockage.