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The purpose of this paper is to provide a systematic method to perform analysis and test for vibration‐thermal strain behavior of plastic ball grid array (PBGA) assembly by considering thermal and vibration loading mode. Also to investigate the dynamic behavior of PBGA assembly by considering loading modes for design and reliability evaluation of PBGA packaging.

A PBGA assembly prototype with different structure and material parameters is designed and manufactured. Based on investigation of the structural and physical parameters of PBGA sample, the vibration‐thermal strain test is developed to measure the strain distribution at the surface of the BT (bismaleimide triazine) substrates and PCB (printed circuit board) surface under vibration‐thermal cycling loading such as random vibration and the temperature is changed from 0°C to 100°C.

The test results show that the loading modes have different impact on PCB, EMC and substrate, respectively. In the meantime, it is shown that the characteristics of the compound mode is not the linear accumulative result by single vibration mode and single thermal loading mode as forecasted. The nonlinear mechanism for these modes application is the future work for progress.

It is very difficult to set up a numerical approach to illustrate the validity of the testing approach because the complex loading modes and the complex structure of PBGA assembly. The research on an accurate mathematical model of the PBGA assembly prototype is a future work.

It implies a potential design characteristic for future application of PBGA assembly. It also builds a basis for future work for design and reliability evaluation of BGA package.

This paper fulfils useful information about the thermal‐vibration coupling dynamic behavior of PBGA assembly with different structure characteristics, materials parameters.

The purpose of this paper is to attempt to establish a grey clustering evaluation model of center-point triangular whitenization weight function to measure the performance of enterprise's management innovation (MI). The author intends to provide some theory basis and tool support for enterprise's managers and other researchers who are engaged in performance measuring.

The study uses questionnaire survey and expert interviews to determine the index weight of enterprise's MI performance (MIP), classifies the grey clusters based on center-point triangular whitenization weight function, calculates the membership of performance criteria and ranks the performance level of all dimensions.

The survey data of case company shows that production performance is in superior level, employee and society influence performance are in satisfied level, finance and market performance are in intermediate level, total MIP is in satisfied level.

MI is the fundamental way to keep enterprise's core competitiveness and achieve its strategic objectives. Performance is an effective tool to measure the MI. Therefore, based on the practices of MI in China, the study systematically clarifies the performance level of MI from five dimensions.

The evaluation index of enterprise's MIP is built with five dimensions which contain production, market, finance, employee and social influence. The grey clustering evaluation model based on triangular whitenization weight function is applied to assess the performance criteria. This paper presents a new research idea for enterprise's performance evaluation.

The purpose of this paper is to upgrade the collaborative emergency ability of government in the tier of towns, realizing emergency resource share, emergency cost reduction and emergency efficiency improving. This paper mainly aims to solve the problem of forecasting the natural disaster happening year of every township collaborative region in Fangshan District.

First, classify the townships into five collaborative regions through grey clustering. Second, set up a grey disaster forecast model for the whole Fangshan District according the annals of disaster from 1985 to 2012, and forecast the disaster grade. Third, build a grey disaster forecast model for the collaborative regions after constructing the buffer operators of catastrophic sequence according the annals of disaster from 1949 to 2012.

The authors forecasted the happening year and flood grade of future disaster for the whole Fangshan District. The accurate degrees of both flood and drought year model are greater than 90 per cent. The accurate degree of insects calamity year is a little low, but the relative errors are all lower than 3 per cent in recent continuous three times, so in the whole, it can be used. For the collaborative regions, the authors forecasted the future disaster years of them. The accuracy rate of every model is greater than 90 per cent. The result shows that the forecast errors are acceptable.

In the models, for the purpose of good accuracy, the authors used different initial data. For example, in the forecast model for whole Fangshan District disaster year, the authors used the data from 1985 to 2012, while in the forecast model for the disaster grade of it, the authors used the data from 1949 to 2012. In the disaster year forecast model for collaborative region, the authors also used the data from 1949 to 2012. If the authors can find a model that has high accuracy rate by using all the date information, it will be better.

Township is the most basic level of government organization in China, researching on collaborative emergency in township will do help to take targeted precautions measures against calamity according to the characteristic there. At the same time realizing emergency cost reduction and emergency efficiency improving based on the advantages of emergency resource share, short rescue distance, little effects of communication destruction.

Because of the stochastic occurring of disasters, it is very important to forecast the happening time of disasters accurately. This paper forecasted the natural disaster happening time of Fangshan District through grey catastrophic model, aimed at giving decision support to related department and strengthen the disaster prevention power targetedly.

It is well known that the greater the system, the steadier it is, and the easier to forecast it. Fangshan District, Beijing, is a medium-sized and small system in regional research, while townships are small systems. It is rarely a big challenge for the authors to forecast the disaster years in Fangshan and its collaborative townships. In this paper, the authors used grey system model and Markov transfer matrix in forecasting the disaster years and the disaster grade of flood in Fangshan District. All of them are new trying to using grey system theory in disaster forecast for Fangshan District, Beijing.

The purpose of this paper is to subject the potential of Internet of Things (IoT) technology for libraries in terms of the possible scope and usage forms of this technology in public and academic library services.

Based on analysis of the subject literature, the main areas of IoT applications in commercial institutions were identified, then an analysis of Library and Information Science English-language literature from the years 2010 to 2015 was conducted in order to create a profile of modern library services. The range of activities of commercial and non-commercial institutions were compared to ascertain if areas in which commercial entities using or planning to use IoT could also be an inspiration for libraries. In this way, a theoretical model of IoT use in library activities was developed.

The research showed that IoT technology might have the potential to be used in library services and other activities, similar to how it is implemented in the commercial sector.

The aim of the paper is to determine the possible, not the actual, scope and forms of using this technology in public and academic libraries’ services.

The results can be widely used in libraries as an inspiration for the use of IoT technology in modern library services.

The use of new technologies in libraries can help to improve the image of these institutions in the eyes of users, especially the younger generation.

The use of IoT in libraries is a new issue that has not been studied much yet. The issue of using the potential of this technology for the needs of libraries has, in recent years, been raised at international conferences, become a subject of interest to librarian associations, and been widely discussed in the blogosphere, thus proving that this topic is important to practitioners. It is difficult, however, to find any scientific, comprehensive studies of this topic.