维持性血液透析病人干体重预测方程的构建和验证

[目的]采用Basile的“四步法”构建基于生物电阻抗分析的维持性血液透析病人干体重预测方程,并对方程进行验证。[方法]便利抽取上海市某三级甲等医院的138例维持性血液透析病人作为血液透析组,选取上海市某三级甲等医院的816名体检者作为对照组,选取上海市其他两所医院的35例维持性血液透析病人作为验证组。对Basile的血液透析病人干体重预测方程构建方法进行调整,利用血液透析组、对照组、验证组人群数据构建并验证适用我国维持性血液透析病人的干体重预测方程。[结果]多元线性回归分析结果显示:397名正常体质指数(BMI)的男性体检者体重与其年龄、身高、50 kHz电阻值(R50)呈线性相关(R2=0.783,P<0.001),378名正常BMI的女性体检者体重与身高、R50呈线性相关(R2=0.662,P<0.001)。矫正后男性维持性血液透析病人干体重=(0.859427×身高-0.025143×年龄-0.034933×R50-59.867424)×透析后BMI/21.76;矫正后女性维持性血液透析病人干体重=(0.697978×身高-0.032994×R50-34.080396)×透析后BMI/20.44。经验证组病人数据验证,结果显示:验证组男性和女性干体重实际值和预测值比较,差异均无统计学意义(P>0.05)。[结论]构建的维持性血液透析病人干体重预测方程对病人干体重的预测值和实际值间有较好一致性,生物电阻抗分析法可以与临床上的其他方法结合起来更好地指导医护人员对病人进行容量管理。

爱因斯坦光电效应方程验证实验中系统误差的发现

提供了发现仪器系统误差和解决的方法,并提供了对仪器进行检修和判断滤光片是否合格的依据。

流体力学实验教学改进研究——介绍气偏球伯努利方程验证仪

介绍了一种在流体力学教学中所使用的新型伯努利方程验证仪.以气体为流体,该装置可以使实验操作更简单,实验现象更直观可感.同时本文也给出了验证方法和实验步骤,并对实验结果进行t测验.

重症脑损伤机械通气患者加温加湿罐水位控制的临床验证效果

目的检验重症脑损伤机械通气患者加温加湿罐水位控制方程Y=1.586+0.057×(滴速)-0.077×(气道温度)的临床应用的准确性,为加湿罐自动、持续注水的速度设置提供依据,减少护士的工作量。方法根据加温加湿罐水位控制方程,制定不同气道温度与呼吸机湿化罐注水速度对应调节表,进而设定加湿罐自动、持续注水速度,通过自制观察表,每4h观察记录一次加湿罐水位变化情况。结果通过临床验证,发现重症脑损伤机械通气患者的气道温度波动在30~36℃,按照加温加湿罐水位控制方程将注水滴速设置为13~21滴/min后,加温加湿罐水位控制合格率为92.8%。结论重症脑损伤机械通气患者加温加湿罐水位控制方程Y(0位线)=1.586+0.057×(滴速)-0.077×(气道温度),可较好地控制加温加湿罐水位,大幅度降低了重症ICU护士的护理工作量。

基于ADAMS和MATTLAB的一种新型球形机器人的联合仿真

利用三维造型软件建立了新型球形机器人的虚拟样机模型,并建立起动力学方程。应用MATLAB/Simulink工具并结合ADAMS/View仿真软件对其运动学方程进行验证。通过数据得出方程的正确性。

Methods of Validating Simulation Model and Program Design

Validating simulation model is one of the important aspects for modeling and simulation. Some methods of validating model are compared and analyzed. Several typical methods, such as TIC’s inequality coefficient, gray interconnected analysis, direct spectrum estimation, maximum entropy spectral estimation based on Burg or Marple, are chosen and programmed in C language. Some examples by using the program are given. The results show that the program is available and it is best to adopt multi methods for validating models.

Translation and validation of the Nepean Dyspepsia Index for functional dyspepsia in China

AIM： To assess the reliability and validity of the translated version of Nepean Dyspepsia Index （NDI） in Chinese patients with documented functional dyspepsia （FO）. METHODS： The translation process included forward translation, back translation, pretest and cross-cultural adaptation. Reliability and validity of the translated version were examined by asking 300 subjects to complete the Chinese version of the NDI. The mean age of subjects was 39.24 years and 68.7% of the subjects were women. Internal consistency analysis with Cronbach＇s α was performed to test the reliability. Correlation analysis was used to assess the content validity. Factor analysis and structural equation models were used to assess the construct validity. RESULTS： The Cronbach＇s α coefficients ranged 0.833-0.960, well above the acceptable level of 0.70. Correlation analysis showed that each item had a strong correlation with the corresponding domain, but a weak correlation with other domains. Confirmatory factor analysis indicated that the comparative fit index was 0.94, higher than the acceptable level of 0.90.CONCLUSION： The Chinese version of the NDI is a reliable and valid scale for measuring health-related quality of life and disease severity in Chinese patients with FD.

Responses of wind-induced internal pressure in a two-compartment building with a dominant opening and background porosity Part 1:Theoretical formulation and experimental verification

The equations governing wind-induced internal pressure responses for a two-compartment building with a dominant opening and background porosity were derived.The unsteady form of the Bernoulli equation,the law of mass conservation,and adiabatic equation were used for the derivation.The precision of the governing equations was verified by a wind tunnel test on a rigid model of a low-rise building.The results show that the governing equations can effectively analyze the wind-induced internal pressure responses.The internal pressure responses in both compartments are suppressed due to the additional damping provided by background porosity.The responses of internal pressure in both compartments,especially in the compartment without an external opening,decrease with increased lumped leakage area.

Verified Solution for a Statically Determinate Truss Structure with Uncertain Node Locations

We consider a statically determinate structural truss problem where all of the physical model parameters are uncertain： not just the material values and applied loads, but also the positions of the nodes are assumed to be inexact but bounded and are represented by intervals. Such uncertainty may typically arise from imprecision during the process of manufacturing or construction, or round-off errors. In this case the application of the finite element method results in a system of linear equations with numerous interval parameters which cannot be solved conventionally. Applying a suitable variable substitution, an iteration method for the solution of a parametric system of linear equations is firstly employed to obtain initial bounds on the node displacements. Thereafter, an interval tightening （pruning） technique is applied, firstly on the element forces and secondly on the node displacements, in order to obtain tight guaranteed enclosures for the interval solutions for the forces and displacements.

Development and experimental validation of a one-dimensional dynamic hygrothermal modeling based on air humidity ratio

A modified one-dimensional transient hygrothermal model for multilayer wall was proposed using air humidity ratio and temperature as the driving potentials.The solution for the governing equations was obtained numerically by implementing the finite-difference scheme.To evaluate the accuracy of the model,a test system was built up to measure relative humidity and temperature within a porous wall and compare with the prediction of the model.The prediction results have good agreement with the experimental results.For the interface close to indoor side,the maximum deviation of temperature between calculated and test data is 1.87 K,and the average deviation is 0.95 K;the maximum deviation of relative humidity is 11.4%,and the average deviation is 5.7%.For the interface close to outdoor side,the maximum deviation of temperature between prediction and measurement is 1.78 K,and the average deviation is 1.1 K;the maximum deviation of relative humidity is 9.9%,and the average deviation is 4.2%.

Dual-channel Method for Fast Long PN-code Acquisition

Long PN-code acquisition is a difficult and time-consuming task due to long code period.To accelerate acquisition,folding methods like XFAST are widely used.In highdynamic environment however,the application of those methods are largely restricted due to nonnegligible residual frequency.This paper proposes a new dual-channel method for fast acquisition of long PN-code.In the proposed method,both non-overlapping local PNcode blocks are employed to correlate with input sample block;the detection process is eased through finding the maximum value among correlation results and verification is made with all the full and partial peaks taken into account.False alarm probabilities from analysis of the verification process are derived.Both theoretical and Monte Carlo simulations reveal that,with respect to acquisition probability and mean acquisition time under the same false alarm rate,dual-channel method has advantage over zero-padding and XFAST based folding methods under certain false alarm probabilities.

Quantum Secure Direct Communication with Authentication Expansion Using Single Photons

In this paper we propose two quantum secure direct communication (QSDC) protocols with authentication.The authentication key expansion method is introduced to improve the life of the keys with security.In the first scheme,the third party, called Trent is introduced to authenticate the users that participate in the communication.He sends thepolarized photons in blocks to authenticate communication parties Alice and Bob using the authentication keys.In thecommunication process, polarized single photons are used to serve as the carriers, which transmit the secret messagesdirectly.The second QSDC process with authentication between two parties is also discussed.

A Confirmatory Factor Analysis on the Views and Constructs for Knowledge Management in India

For a modem organization, KM （Knowledge Management） plays a critical role in terms of strategy development. Key determinants of KM lead to better understanding of various influences that enable and organisation to face competitors. For this reason, sharing and managing knowledge in an organization involves a series of activities that are related to the specific functional aspects of that organisation. In order to foster KM in an organisation, these functional aspects must be understood properly, and within the context of a given organisation, its geographical location and the cultural aspects of the given organisation. This was the premise on which this study was conducted with Indian organisations. A mixed method approach was used to understand the views of Indian region towards KM in this study, be selecting 400 participants in four major each cities. A second order regression model was built using Structural Equation Model to arrive at nine constructs that are relevant to KM in an organisation.

Photochemical Degradation of the Ciprofloxacin Antibiotic and Its Microbiological Validation

In this research, it used advanced oxidation processes for the recovery, detoxification and mineralization of wastewater mainly contaminated by antibiotics （ciprofloxacin）. These processes can be used alone or in combination with each other or by complementing traditional methods, even allowing the disinfection of bacterial and viral inactivation. With the use of experimental systems UV/H202/O3, UV/H202, it can achieve total mineralization of the compound. Ciprofloxacin solutions used at 50, 100, 200, 300, 400 and 500 ppm, degraded to 100% of antibiotics and by a microbiological method show that the loss of biological activity is inversely proportional to the time of irradiation.

Recent Advances to Change the Standards in Designing Hulls in Waves, a Validation Using an Efficient SWENSE Level-Set Approach

This paper presents recent naval applications of the SWENSE （Spectral Wave Explicit Navier-Stokes Equations） approach implemented for the first time with high order fully unstructured schemes and an efficient level-set method to capture free surface flows around realistic hull geometries. Numerical simulations in waves and/or viscous flows still lead generally to very large CPU times because of grid requirements to ensure a good propagation of incident waves in the meshed part of the fluid domain that makes unreachable any hull design optimization process in an industrial context. Furthermore, even if the SWENSE method clearly shows promising results in an academic context in both regular and irregular waves, the most recent publications still highlight several issues that remain unresolved up to now, e.g. poor scalability, diffusive wake pattern, non-versatile structured mesh approaches and only very few validation test cases are carried out on Wigley or DTMB 5415 hulls. In order to overcome those numerical difficulties and get an in-depth validation of the method on several cases in realistic wave conditions, a two and a half years＇ research project has been achieved involving several steps, starting by a set of dedicated model test experiments later used as reference for the validation of the method. The CFD commercial code ANANASTM used and developed in this research program is presented and validated in detail. The use of high order schemes on unstructured grids in combination with these SWENSE method and level-set approach offer to the maritime industry an innovative and state of the art method to achieve unequaled accuracy, low computation time and some unique advantages such as, amongst others, the end of the numerical wave propagation problems. The results of the validation were pleasing and can be considered as acceptable in general, with some challenges remaining to the solyed. Results obtained indicate that an optimization processes in waves in realistic conditions is now affordable in an industrial context.

大学生精神性、社区感与幸福感的比较及相互关系探讨

研究比较了大学生精神性、社区感、幸福感在人口学变量上的差异,并探讨了三者之间的关系。结果发现:(1)大学男生的内向性、社会外向性、社区感和幸福感显著高于女生,女生的个人外向性显著高于男生;大三、大四学生的社区感显著高于大一、大二学生,大三、大四学生的幸福感显著高于大二学生。(2)大学生精神性、社区感和幸福感的结构方程分析表明,该模型的整体拟合优度良好。(3)内向性对社区感、幸福感的直接效应和间接效应显著,内向性对幸福感具有整体效应。

CFD investigation and PIV validation of flow field in a compact return diffuser under strong part-load conditions

The internal flow fields in a compact return diffuser under strong part-load conditions are investigated both numerically and experimentally.For numerical simulation,three-dimensional unsteady Reynolds-Averaged Navier–Stokes equations are solved on high-quality structured grids in conjunction with the shear stress transport k–turbulence model by employing the computational fluid dynamics(CFD)software ANSYS-Fluent 14.5.For flow field measurements,a special test rig is designed and the two-dimensional particle image velocimetry(PIV)measurements are conducted in the diffuser midplane to capture the complex flow field and for validation of the CFD results.The analysis of the results has been focused on the flow structure in the diffuser,especially under part-load conditions.The detailed comparison between CFD and PIV results is performed.Vortical flow and recirculation flow patterns in the diffuser are captured and analyzed.Large flow separation and backflow appear under the part-load flow conditions.This paper provides a good data set for developing as well as evaluating the accuracy of various CFD models for capturing the complex flow field in a compact return diffuser used with multistage pumps.

Numerical Investigation of an Oscillating Airfoil using Immersed Boundary Method

Based on the immersed boundary method, a numerical simulation for an oscillating airfoil is established and a preliminary analysis of the oscillating airfoil is presented with an emphasis on the physical understanding of fluid-structure interaction. In order to validate the method, two simulation cases： oscillating circular cylinder at low K-C number and two degrees of freedom oscillating cylinder are carded out first and the results are in good agreement with the previous re：searches. In the oscillating airfoil simulation, it is found that the reduced velocity U^＊. is a very sensitive factor and especially U^＊-2.8 is the critical stable boundary in the present work. The method shows the predominance of time saving in computational process for such a complicated fluid-structure interac- tion problem.

The stability analysis of rolling motion of hypersonic vehicles and its validations

The stability of the rolling motion of near space hypersonic vehicles with rudder control is studied using method of qualitative analysis of nonlinear differential equations, and the stability criteria of the deflected rolling motions are improved. The out- comes can serve as the basis for further study regarding the influence of pitching and lateral motion on the stability of rolling motion. To validate the theoretical results, numerical simulations were do^e for the rolling motion of two hypersonic vehicles with typical configurations. Also, wind tunnel experiments for four aircraft models with typical configurations have been done. The results show that： 1） there exist two dynamic patterns of the rolling motion under statically stable condition. The first one is point attractor, for which the motion of aircraft returns to the original state. The second is periodic attractor, for which the aircraft rolls periodically. 2） Under statically unstable condition, there exist three dynamic patterns of rolling motion, namely, the point attractor, periodic attractor around deflected state of rolling motion, and double periodic attractors or chaotic attrac- tors.

Study and verification on dispersion coefficient in wave field

Transport and diffusion caused by coastal waves have different characteristics from those induced by flows. Through solving the vertical diffusion equation by an analytic method, this paper infers a theoretical formula of dispersion coefficient under the combined action of current and waves. It divides the general dispersion coefficient into six parts, including coefficients due to tidal current, Stokes drift, wave oscillation and interaction among them. It draws a conclusion that the contribution of dispersive effect induced by coastal waves is mainly produced by Stokes drift, while the contributions to time-averaged dispersion coefficient due to wave orbital motion and interaction between current and waves are very small. The results without tidal current are in agreement with the numerical and experimental results, which proves the correctness of the theoretical derivation. This paper introduces the variation characteristics of both the time-averaged and oscillating dispersion coefficients versus relative water depth, and demonstrates the physical implications of the oscillating mixing coefficient due to waves. We also apply the results to the costal vertical circulation and give its characteristics compared to Stokes drift.