BIM算量与传统算量量差原因分析

近年来,我国大力推行建筑信息模型BIM技术的应用,在工程造价领域,BIM模型与传统算量软件都通过建立模型而得出一个建设项目的工程量。研究了基于BIM技术的Revit比目云与传统的手工算量、软件算量这三种方式的量差,并对其量差进行了分析。研究结果表明,从设计阶段开始就应用Revit模型,并依据Revit模型和比目云5D进行工程量计算,具有可行性并且有较高的精确度,能有效地提高工程造价行业的算量、计价效率,使得算量更加精细化、智能化。

经济收益、会计收益与应税收益的比较

收益是经济学、会计学、税法上的一个重要概念,它在社会经济生活中的地位与作用正日益被人们所认识理解。三种不同的收益概念--经济收益、会计收益与应税收益,充分体现了收益确认与计量的复杂性。通过三种收益之间的"量差"分析则使我们认识到会计收益概念向经济收益概念发展的必要性和可行性;以及会计收益与应税收益的差异扩大化是会计与税法双方不断完善健全的必然结果。

对传统管理会计控制模式的几点思考

该文对传统管理会计下的控制模式的基本内容及其存在的问题进行了实证分析,并就新的制造环境和管理理念的变化提出了现代管理会计控制模式应包含的基本要素和应达到的标准,同时就其在实践中可能存在和应引起注意的问题提出了一些个人的建议。

Research of the wave measurement using GPS absolute velocity estimation technology

This paper analyzed the existing methods of wave measurement, and described the advantages of GPS applied in measuring the wave. The equations of absolute velocity estimation were discussed, focusing on two methods with Doppler shill. The error sources and their effect on velocity estimation were analyzed. Then, some tests were carried on to simulate dynamic velocity determination using static data Based on the high-frequency carrier-phase derived Doppler observations, the velocity has been estimated to the precision of 1 cm/s or so, even to the mm/s level. And with the receiver generated Doppler measurements, the precision can reach 3 - 15 cm/s.

Measurement of Coordinate Parameter by Multi-baseline Digital Close-range Photogrammetry System and Data Analysis for Jujube

[Objective] The aim was to explore the measurement of coordinate parameter by multi-baseline digital close-range photogrammetry system.[Method] The 3-dimensional coordinate of 8-year-old Jujube was measured by using Lensphoto multi-baseline digital close-range photogrammetry system,and through comparing with measured data of Total Station,the error and accuracy of photogrammetry data were analyzed.[Result] The absolute error of X,Y and Z coordinate was 0-0.014,0-0.018 and 0-0.004 m respectively,and the relative error of X,Y and Z coordinate was less than 0.145%.The significance test of pairs for the photogrammetry data and measured data of Total Station indicated that the space coordinate data of stumpage were accurately measured by using the multi-baseline digital close-range photogrammetry method,and the photogrammetry data meet the need of space coordinate measurement for virtual plant growth simulation.[Conclusion] This study had provided theoretical basis for the growth measurement of virtual plant growth simulation.

APPLICATION OF CHAOS IN MEASUREMENT

Using the high sensitivity to initial values of chaotic systems, this paper describes an application of chaos in the field of measurement. A general method for signal coding based on symbolic sequences and the relationship between the variable (to be measured) and its symbolic sequence are presented. Some performances of the chaos based measurement system are also discussed. Theoretical analysis and experimental results show that chaotic systems are potentially attractive in the field of measurement.

基于BIM的工程算量模式可靠性对比研究

为寻求设计阶段基于BIM的工程量信息与施工预算模型工程量信息的有效对接和传递,针对现有应用程序编程接口及BIM设计软件自动算量2种算量模式的可靠性开展研究,提出分别从模型图元转化的完整性和工程量转化的准确性等不同指标予以验证的方法,并基于某实际工程,以利用广联达土建算量软件建立的GCL模型作为准确工程量来源,分别与3种方式得到的BIM模型量值进行对比分析,结果表明将Revit模型以GFC数据格式导入到广联达土建算量软件计算汇总工程量的模式可靠性较高。

Apparent activation energy for spontaneous combustion of sulfide concentrates in storage yard

In order to evaluate the spontaneous combustion hazard of sulfide concentrates in storage, three different kinds of sulfide concentrates （sulfur-rich sulfide concentrate, iron sulfide concentrate and copper sulfide concentrate） were obtained from a storage yard in Dongguashan Copper Mine, China. The reaction processes at different heating rates of 5, 10, 15, 20, and 25 ℃/min in air flow from ambient temperature to 1 000 ℃ were studied by TG-DTG-DSC analysis. By the peak temperatures of DTG curves, the whole reaction process for each sample was divided into different stages, and the corresponding apparent activation energies were calculated by the Ozawa-Flynn-Wall method. It is found that the reaction process of each sample is considerably complex; the apparent activation energy values change from 36 to 160 kJ/mol in different temperature ranges; sulfur-rich sulfide and iron sulfide concentrates have lower apparent activation energy than copper sulfide concentrate below 150 ℃; so they are more inclined to cause spontaneous combustion at ambient temperature.

基于BIM技术的柱构件钢筋算量研究--以呼和浩特市赛罕区人民医院北住院楼为例

在工程项目中,工程量的提取是BIM技术得以发挥自身价值的重要应用之一。由于钢筋工程具有很高的专业性,所以钢筋工程量的提取一直是BIM技术应用的重难点之一,如何快速且准确地提取结构构件的钢筋工程量是各单位在BIM技术应用过程中关注的重点。文章以呼和浩特市赛罕区人民医院北住院楼柱构件钢筋为例,以平法图集16G101-1为参照,通过手算钢筋工程量和BIM技术所出具的钢筋工程量为依据,对计算所得的数据进行比对,研究与实证分析发现,软件内置的钢筋节点计算规则与平法图集完全吻合,且手算与通过BIM技术计算的钢筋工程量结果一致。应用BIM技术可以大大提高工作效率,推动建筑行业提升工业信息化水平。

能源计量的监测系统及在实际工作中的应用

介绍能源集中管理及其在实际工作中的应用。

Continuous cooling precipitation diagram of high alloyed Al-Zn-Mg-Cu 7049A alloy

The precipitation behaviour during cooling from solution annealing of high alloyed 7049A aluminium alloy was investigated, covering the complete cooling-rate-range of technical interest. This ranges from slow cooling rates close to equilibrium up to rates above complete supersaturation and is covering seven orders of magnitude in cooling rate （0.0005 to 5000 K/s）. The continuous cooling precipitation behaviour of 7049A alloy was recorded by combining different differential scanning calorimetry （DSC） techniques and microstructure analysis by SEM and Vickers hardness testing. The high alloyed, high strength and quench sensitive wrought aluminium alloy 7049A was investigated during quenching from solution annealing by conventional DSC in the cooling rate range of 0.0005 to 4 K/s. In this range at least two exothermal precipitation reactions were observed： a high temperature reaction in a narrow temperature interval of 450-430℃, and a low temperature reaction in a broad temperature interval down to about 200 ℃. Intensities of both reactions decreased with increasing cooling rate. Quenching from solution annealing with rates up to 1000 K/s was investigated by differential fast scanning calorimetry （DFSC） and the differential reheating method （DRM）. A critical quenching rate to suppress all precipitation reactions of 100-300 K/s was been determined.

A Multivariate Public Key Cryptographic Scheme

This paper presents a multivariate public key cryptographic scheme over a finite field with odd prime characteristic.The idea of embedding and layering is manifested in its construction.The security of the scheme is analyzed in detail,and this paper indicates that the scheme can withstand the up to date differential cryptanalysis.We give heuristic arguments to show that this scheme resists all known attacks.

Comparison of Meiofaunal Abundance in Two Mangrove Wetlands in Tong'an Bay, Xiamen, China

To compare meiofaunal community in the two mangrove wetlands in Tong＇an Bay, Xiamen, China, and probe the response of meiofauna to high organic matter, sampling was carried out in Fenglin and Xiang＇an mangrove wetlands in the bay. The results showed that the Ne/Co ratio （nematode to benthic copepod） and organic matter in Fenglin mangrove wetland were higher than those in Xiang＇an mangrove wetland. The meiofaunal abundance in Fenglin mangrove was all lower than that in Xiang＇an mangrove wetland in summer, autumn and spring, while the meiofaunal abundance in Fenglin mangrove was higher than that in Xiang＇an mangrove wetland in winter. Two-way ANOVA results showed that the meiofaunal abundance and nematode abundance were significantly different between regions, seasons and regionxseason. With all the results in the present study, we confirmed that the positive response of meiofaunal and nematode abundance were only detected for medium organic matter contents according to the Xiang＇an wetland＇s level, and that the distribution of meiofaunal abundance would be influenced by sand content. Higher copepod abundance and lower N/C value usually suggest better environmental quality.

Thermo-analysis of Preparation Processfor Electron Trapping Materials

The heated process of raw materials for electron trapping materials (ETM) is investigated by thermo-analysis method. The temperature ranges of raw materials experienced some physical and chemical change processes, such as dehydration, organic solvent removal, crystal sulphur burning, oxidation of alkaline earth sulfides and solid phase reaction (rare earth doped) and so on, are obtained. The experimental results also show that the presence of trace oxygen in shielded gas is very harmful to prepare the ETM.The raw material thermo-analysis results provide very important experimental reference for optimizing the ETM preparation techniques.

Analytical Model for Calculating Trapped Charge in a－Si：H and Its Relative Error Analysis

Using a Taylor series expansion for the Fermi-Dirac occupation function,an accurate analytical model is developed for calculating the trapped-charge density in a-Si: H considering deep and tail states simultaneously without simplification.This is followed by the investigation of the relative errors of the localized trapped charge density in a-Si:H at all temperatures as a function of the quasi-Fermi level in the band gap calculated from three published analytical models and our above model. The results suggest that the relative errors of all these models increase notably as Efn is very closed to Ec(e.g.,-0.01 eV< Efn-Ec).It is also noticed that the relative errors of all above models become larger normally the greater is the value of temperature.A detailed analysis indicates that each model has its own applicability with various temperatures and various positions of the Fermi level.

Normative Versus Perceptual Gap Analysis of Hotel Product Quality as a Service to Tourism in Kenya

Kenya＇s tourism business stagnated from 1991 to 2003 and only registered small but steady grew from 2004. One of the sectors that recorded poor performance as a result of the slow growth of tourism is the hotel business. Despite this slack, stakeholders in Kenya have not tried to assess the extent to which the quality of this sector may impact on destination preference. The ultimate purpose of this research was to establish the quality gap between the expected and the perceived hotel product/service quality from both the perspective of the tourists and the hotel operators in Kenya. It was motivated by the need to create parameters that can elavate the competitiveness of Kenya＇s tourism using the hotel product/service quality offer. Descriptive quantitative research design was used to establish the secondary objectives and to assess two propositions set for the study. A sample of 211 tourists and 19 hotel operators in two major tourist provinces of Kenya was used to obtain information regarding normative and perceptive hotel product/service quality. Kenya＇s only destination marketing organisation, Kenya Tourist Board （KTB） marketers were also surveyed to provide insight on Kenya＇s destination position with regard to the motivation of tourists to visit Kenya. The study established that although the attractions which make tourists come to Kenya are the unique wildlife safari, beach tourism and the natural scenery, hotel product quality and hospitality plays a vital role in motivating tourists to choose Kenya as the destination to visit. However, this study found out that while the tourists and hotel operators agree on the normative hotel product quality level, there is a significant gap between the normative quality and the perceptual quality registered by tourists who used hotel services. The study established that hotel operators only recognize quality regulatory institutions with statutory and legal authority to incriminate facilities that do not comply with laid down operational requirements such as Hotels and Restaurants Authority and the Local Authority Public Health Department. The study has proposed an integrated framework that may be utilized to build a superior national hotel product/service quality so that the economic potential of tourism is maximized in Kenya.

Automatically detecting auditory P300 in several trials

A method was demonstrated based on Infomax independent component analysis(Infomax ICA) for automatically extracting auditory P300 signals within several trials. A signaling equilibrium algorithm was proposed to enhance the effectiveness of the Infomax ICA decomposition. After the mixed signal was decomposed by Infomax ICA, the independent component(IC) used in auditory P300 reconstruction was automatically chosen by using the standard deviation of the fixed temporal pattern. And the result of auditory P300 was reconstructed using the selected ICs. The experimental results show that the auditory P300 can be detected automatically within five trials. The Pearson correlation coefficient between the standard signal and the signal detected using the proposed method is significantly greater than that between the standard signal and the signal detected using the average method within five trials. The wave pattern result obtained using the proposed algorithm is better and more similar to the standard signal than that obtained by the average method for the same number of trials. Therefore, the proposed method can automatically detect the effective auditory P300 within several trials.

Submarine Pipeline Routing Risk Quantitative Analysis

A new method for submarine pipeline routing risk quantitative analysis was provided, and the study was developed from qualitative analysis to quantitative analysis.The characteristics of the potential risk of the submarine pipeline system were considered, and grey-mode identification theory was used. The study process was composed of three parts: establishing the indexes system of routing risk quantitative analysis, establishing the model of grey-mode identification for routing risk quantitative analysis, and establishing the standard of mode identification result. It is shown that this model can directly and concisely reflect the hazard degree of the routing through computing example, and prepares the routing selection for the future.

Some Peculiarities of the Preprocessing of Spectral Data and Images

Remotely sensed spectral data and images are acquired under significant additional effects accompanying their major formation process, which greatly determine measurement accuracy. In order to be used in subsequent quantitative analysis and assessment, this data should be subject to preliminary processing aiming to improve its accuracy and credibility. The paper considers some major problems related with preliminary processing of remotely sensed spectral data and images. The major factors are analyzed, which affect the occurrence of data noise or uncertainties and the methods for reduction or removal thereof. Assessment is made of the extent to which available equipment and technologies may help reduce measurement errors.

Time-Frequency Analysis of EEG Signals Evoked by Voluntary, Stimulated and Imaginary Motions

In order to investigate the characteristics of sensorimotor cortex during motor execution(ME), voluntary, stimulated and imaginary finger flexions were performed by ten volunteer subjects. Electroencephalogram(EEG) data were recorded according to the modified 10-20 International EEG System. The patterns were compared by the analysis of the motion-evoked EEG signals focusing on the contralateral(C3) and ipsilateral(C4) channels for hemispheric differences. The EEG energy distributions at alpha(8—13 Hz), beta(14—30 Hz) and gamma(30—50 Hz) bands were computed by wavelet transform(WT) and compared by the analysis of variance(ANOVA). The timefrequency(TF) analysis indicated that there existed a contralateral dominance of alpha post-movement event-related synchronization(ERS) pattern during the voluntary task, and that the energy of alpha band increased in the ipsilateral area during the stimulated(median nerve of wrist) task. Besides, the contralateral alpha and beta event-related desynchronization(ERD) patterns were observed in both stimulated and imaginary tasks. Another significant difference was found in the mean power values of gamma band(p<0.01)between the imaginary and other tasks. The results show that significant hemispheric differences such as alpha and beta band EEG energy distributions and TF changing phenomena(ERS/ERD) were found between C3 and C4 areas during all of the three patterns. The largest energy distribution was always at the alpha band for each task.