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The field measurement of wind-induced response is of great significance to the wind resistance design of high-rise buildings, in particular torsional responses measured from high-rise buildings under typhoons. The measured high-rise building, with a height of 108 m, has 32 stories and is supported by giant trusses with four massive columns. Acceleration responses along translational and torsional directions were monitored synchronously and continuously during the passage of Typhoon Sarika on 18 October 2016. The wind speed and wind direction at the height of 115 m, the translational accelerations on a total of six floors and the angular accelerations on a total of four floors were recorded. The time and frequency domain characteristics of translational acceleration and torsional angular accelerations were analyzed. The amplitude-dependent translational and torsional modal frequencies of the measured building were identified by NExT-ERA, SSI, and RDT methods. The full-scale study is expected to provide useful information on the wind-resistant design of high-rise buildings in typhoon-prone regions.

Electronics installed in modern complex systems, like automotive and aircraft systems, are mainly subjected to mechanical vibrations in applications. The interconnection structure, as the mechanical fixing and electrical interconnection between the electrical device and the printed circuit board, is a key part in electronics. Presently, there are few researching articles on reliability of QFP interconnect structure under random vibration. In this paper, eight specimens of QFP100 with the self-testing real-time circuit have been tested to failure by subjecting to a narrow-band random vibration at its first natural frequency. The charging time of external capacitor in the self-test circuit has been extracted as the monitoring signal. Failure modes of interconnect structure have been analyzed in statistics. Then, the relationship between the monitoring signal and interconnect failure has been investigated. Finally, failure data, conforms to a two-parameter Weibull distribution, has been used to establish the life distribution of interconnect structure. Results show that there are four failure modes and three failure places in interconnect structure under random vibration, which is consistent with simulation results by FEM, and the charging time can characterize the failure and failure process of interconnect structure well.

Nowadays, electronic equipment plays a key and important role in equipment and system, especially with the development of informatization. The failure of interconnect between the chip and PCB, is a major failure mode in electronic equipment, and vibration and temperature are the main environmental factors leading to solder joint failure, which are also the focus of this paper. This study analyzes the failure of QFP chip by random vibration test under three different temperature conditions. The test piece of QFP chip has a self-monitoring circuit, which can monitor its own state whether it is invalid or not. Firstly, the failure of interconnection structure and the effect of their location on reliability has been investigated. Then, the effect of temperature on vibration reliability for interconnection structures has been analyzed. Finally, combined with the exponential distribution of the interconnection structure, the random vibration reliability of the whole chip at different temperatures is evaluated. The results indicate that the interconnection structure of the same chip has similar failure modes, while the crack growth rate is various due to their location, resulting in the difference in their life. Failure modes of interconnect under 25°C and 75°C are similar, which different from failure modes under -25°C, and low temperature reduces vibration reliability of interconnection structure.

In electronic assemblies, quad flat package (QFP) is a widely used packaging method and its interconnection structure degradation is an important field in electronic reliability research. Although degradation processes and failure modes of QFP are various, presently, there are few researching articles on the degradation regularity and mechanism under the same failure mode. In this paper, QFP degradation experiment has been carried out. Three typical QFP degradation processes and failure modes are obtained by experiment data and crack microscopic analysis. Degradation features and curves are extracted through the health index from fusion of dynamic principal component and Mahalanobis distance(PCMD). The regularity shows that there is a similar inflection point in degradation rate curves, and degradation rates are significantly different after this point. Then, according to Darveaux failure physical model, the strain energy distribution of the crack initiation and propagation area is obtained by finite element simulation. Results show that average strain energy density in crack initiation area is similar but in crack propagation area is not, resulting in crack initiation at similar time but the crack propagation rate is different.

Title compounds are conveniently synthesized via TfOH-SiO2 catalyzed intramolecular Friedel—Crafts reaction of the corresponding 2-aryloxy-1-arylethanones.

With the increasing of vehicle quantity, traffic violations occur frequently. It is an efficient means to avoid traffic accident through controlling traffic violation. Based on the study of traffic accidents, black spot of traffic violation can be determined. But little research work has been done on this subject at present. This paper proposed a traffic violation black spot analysis method. In the method, SVM is used to forecast the future traffic violation frequency rate and weight method is used to identify the black spot. The efficiency of the proposed method is illustrated through analyzing a practical example.

This paper builds up supply chain synergy marketing game model based on retailer investment level and manufactory investment level, applying the game theory to analyze the game methods of the manufactory and retailer under the different structure markets, It is discussed the related factor which different marketing mode influenced manufactory and retailer profits level, It is studied the synergy marketing game model and found out the superior acceptable pareto-optimal solution to both the manufactory and retailer.

This paper aims to obtain some "universal method and result" to quantitatively analyze the influence of contact resistance (CR) on OTFTs, which has not been reported up to now. This is partly achieved by means of the simulated method and the introduction of Rc/Rch0 (the value of CR/on state channel resistance). To do this, the OTFT formula from the Brown model is extended, and the parameter (errors carrier mobility μ, saturation voltage VDsat, etc.) caused by Rc are analyzed in detail. Then, the Rc/Rch0 test method is emphatically demonstrated, and some meaningful conclusions are drawn. Based on the conclusion, it is the first time that a "universal method" of estimating the errors caused by Rc has been put forward. Experimental results further prove that the method is correct.