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The core objective of this study is to explore the application of BIM technology in the whole process of cost management of construction projects and to assess the project risk. The study covers the key stages of project planning, design, transaction and construction, and focuses on analyzing the cost management process of investment decision, design estimate, transaction and construction. Through questionnaire surveys and expert interviews with 72 valid samples, this study collects data on green building and analyzes the quality of the risk assessment data. Through questionnaire survey and expert interviews with 72 good samples, this study collects data on green building and analyzes the quality of the risk assessment data. In establishing the BIM-based project cost risk model, the study analyzes the management elements of BIM and IPD in detail, including the quantification of technical and management components. three case projects show that the application of BIM and IPD technologies in different projects has different focuses, and produces other management effects. for example, the number of engineering changes (e.g., the number of changes to the project) exhibited by the project B For example, the number of project changes (NCO) is 35, the cost change rate (COP) is 0.93%, the duration change rate (DCP) is −10.25%, and the number of contract negotiations (NRFI) is 6. The risk evaluation model is applied in a mixed-use project in Xiamen, China, and the results of the simulation experiments show that the method is effective in realizing the risk assessment of the construction project, and the clustered nature of the output features is good. The average value of the risk fuzzy variable is 0.576, and the minimum value is 0.192.

In this article, a high selectivity mm‐wave filter chip based on integrated passive devicies (IPD) technology is proposed. Two adjustable transmission zeros are introduced on both sides of the passband to achieve high roll‐off characteristic. The odd‐even equivalent circuits are used to analyze and calculate the S‐parameters, and the procedure to design a filter is given. Finally, two filter chips with different bandwidths are manufactured based on IPD technology. The measured results show that the minimum insertion losses of the two chips are 1.82 and 1.39 dB, respectively, and their return losses are better than 15 dB. In addition, their roll‐off and stopband suppression are of high level, and the chip sizes are only about 2.8 × 2 mm2. [ABSTRACT FROM AUTHOR]

In this letter, a novel lumped Wilkinson power divider (WPD) introducing capacitors on the isolation R of ultra wideband with good isolation and insertion loss (IL) performance is proposed with the help of gallium arsenide (GaAs) technology. With the even and odd method, the proposed WPD is better illustrated. The fractional bandwidth (FBW) is 104% (3–9.5 GHz). Besides, the return loss is better than 13.7 dB, and the IL is better than 0.62 dB within the passband. The isolation is better than 19.5 dB from 3 to 9.5 GHz. Finally, to better illustrate the design conception, it has been fabricated on GaAs integrated passive device technology with size of 1.37 × 0.971 mm2, that is, 0.1 × 0.072 λg2, measured by on‐wafer probing. All the final results of the proposed WPD are reasonably matched well. [ABSTRACT FROM AUTHOR]

In this article, a novel topology of wideband on‐chip Wilkinson power divider (WPD) with good insertion loss (IL) performance is proposed and demonstrated on gallium arsenide (GaAs)‐based integrated passive device (IPD) technology. The proposed WPD is further analyzed by the even and odd method. To verify the advantage of the proposed WPD against the conventional one, two examples are numerically investigated, showing that the proposed one achieves better performance in terms of IL and isolation. In addition, the proposed design achieves a miniature area and small amplitude and phase imbalance (AI) performance. The fractional bandwidth (FBW) of the proposed WPD is 100% (6‐18 GHz), where the magnitude imbalance is less than 0.08 dB and phase imbalance is better than 0.4°. Furthermore, the minimum IL is better than 0.96 dB and return loss is better than 13.7 dB within the core passband. Meanwhile, the isolation of the WPD is better than 17.6 dB. Finally, to further demonstrate our design conception, the proposed WPD has been fabricated on GaAs IPD technology with size of 1.5 × 0.9 mm2, and measured by on‐wafer probing. All the simulated and measured results of the proposed WPD are matched reasonably well with each other, thus firmly validating the claimed superior performance of the proposed WPD in the wide operating bandwidth, low IL, and high isolation. [ABSTRACT FROM AUTHOR]

In this paper, we present a new wideband miniature branchline coupler as a key circuit to be integrated in 60-GHz packaged beamforming networks for phased-array antennas. First, the integrated passive device (IPD) technology from STMicroelectronics is investigated in the mm-wave range through the simulation, fabrication, and measurements of a microstrip line and a simple hybrid coupler. Then, a novel coupler topology with emphasis on miniaturization and broadband operation is theorized. Analytical equations are derived and a 60-GHz coupler is optimized on IPD technology. Measurement results are discussed and compared with state-of-the art publications. The whole 57–66-GHz bandwidth is efficiently covered with the three following performance: -10\-dB impedance matching, \pm1\-dB amplitude imbalance, and \pm5^\circ phase imbalance. As an application example, the novel coupler is integrated into a 4 $\,\times\,$ 4 Butler matrix suitable for an array-antenna demonstrating state-of-the art performance in terms of insertion loss and phase error. The measurement of different samples shows low variation of the IPD process because of very good reproducibility making it a suitable candidate for circuits operating in the 60-GHz band. [ABSTRACT FROM AUTHOR]

The integration of a Vivaldi antenna on a printed circuit board (PCB) targeting 60-GHz WiGig applications is presented in this letter. The integrated passive device (IPD)technology from STM icroelectronics based on a glass substrate is used for the antenna manufacturing. In free space, the radiation pattern measurements show a realized gain higher than 4 dBi in the end fire direction from 56 to 65 GHz. The impact of the integration of the antenna on the PCB is investigated in details showing reasonable disturbance of the reflection coefficient, but strong modifications of the radiation pattern, especially the pointing direction of the main beam. From the analysis of the surface waves propagating along the PCB when the Vivaldi is integrated, a novel topology is proposed to preserve the main radiation in the end fire direction with enhanced realized gain. [ABSTRACT FROM AUTHOR]

A bandpass filter (BPF) with a central frequency of 2.31 GHz for future worldwide interoperability for microwave access (WiMax) applications using integrated passive device technology is presented. To realise the BPF, an interdigital capacitor is integrated between the two divisions of a square‐shaped spiral inductor. To achieve a compact size, the capacitor is fully embedded inside the inductor. Additionally, the coils of the inductor are intertwined to utilise enhanced mutual inductance for minimising the loss of signal transmission. The strong electromagnetic coupling between the source and load through the interdigital capacitor results in excellent bandpass skirt selectivity with a measured return loss of 26.1 dB. Moreover, it provides an improved stopband response due to the presence of a transmission zero at 5.94 GHz. [ABSTRACT FROM AUTHOR]