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With the rapidly growing of real-time social media, like Twitter, many users share and discuss their interest topics through such platforms. Hashtag is a type of metadata tag which allows users to annotate their topics of tweets. For research usage, for example, hashtags can help the performance of event detection by observing the trend of hashtags. Although Twitter grows rapidly, hashtag growth is not as expected. Our dataset shows that there are less than 20% of all tweets containing hashtags. We think that it is caused by that most users may have no idea what hashtags are suitable for tweets they post. If we can recommend suitable hashtags to users, it can be one of the solutions to solve the problem of low usage rate of hashtag. Hashtag recommendation belongs to supervised learning problem. More labeled data for training the learning model can get higher performance in prediction. However, labeled data in hashtag recommendation is not so much due to low usage rate of hashtag. Thus, we want to exploit unlabeled data, i.e. non-hashtag tweets, to solve this problem. Now we have large amount of unlabeled data, but directly adding all non-hashtag tweets may not be helpful to train the model. To overcome this issue, we apply the weight-updating mechanisms to filter out the useless parts of non-hashtag tweets. These mechanisms also have to consider the temporal characteristics of hashtag due to the real-time nature of Twitter. The experimental results in this research show that adding non-hashtag tweets to extend original training data outperforms baseline methods which only exploit labeled data to train the model.

This investigation on a gateway with an embedded system in Internet of Things (IoT). It presents an intelligent architecture which consists of a large number of sensing objects for monitoring purposes. To collect continuous, periodic and sequential spatial telematics, an embedded system-based gateway that is based on an ARM9 processor is implemented on a test-bed platform. The limitations of IoT are the power consumption of the wireless sensors, ease of handling the communication interfaces and the coverage. Finally, a gateway with multi interfaces for an end-to-end intelligent monitoring system is developed and its routing functionality for heterogeneous network access in IoT is also investigated.

Accelerometer is an important component in INS. Low cost MEMS accelerometers often provide poor accuracy and make system divergent rapidly. This paper provides another way to use accelerometer. Mounting accelerometer on wheel, one can get accuracy angular velocity and degree of wheel, then vehicle's speed and passing distance can be calculated accurately. A self-made concept system was verified that the error of the system is about 15m over 967m integrated path.

Hybrid-monohull is a kind of high performance ship which can reduce longitudinal motion by adding viscous and lifting dampinging. It has been proved that it can sail steadily with high speed in waves. The prediction results of hybrid-monohull using strip method based on potential theory can't reflect its reducing effect. The reason lies on the ignoring of viscous effect. However viscous dampinging plays an important part in total dampinging, so the dampinging coefficients have to be modified. In this paper the hydrodynamic coefficients of bow where built-up appendage is fixed will be calculated using 2-D and 3-D viscous fluid numerical methods. And RANS method is used for calculating the lifting dampinging of built-up appendage. The calculated results indicate that the method used in this paper can reflect the reducing effect obviously, and the precision of prediction is much more improved. The the prediction precision of 2-D method is a little worse than 3-D method. In one word, the method based on viscous hydro-coefficients calculation can predict the motion of hybrid-monohull efficiently.

Evaluation index system is the basis of evaluating the credit of project managers in construction enterprises. To evaluate the credit of project managers in construction enterprises scientifically and normatively, the affecting elements of the project manager's credit was comprehensively analyzed, and by analyzing the subjection and correlativity of the indexes according to the sample data, the qualitative and quantitative credit evaluation index system was finally established based on the characteristics of construction project management. There is some directive significance on the credit evaluation of project managers for construction enterprises and credit rating organizations.

The improper use of exception handling mechanism will affect the efficiency of the application development in programming, so this paper analyzed and summarized several exception fault types for the exception fault problem of AspectJ, and gave the corresponding examples to analyze the impact of exception fault on program control flow, so that the developers can better avoid or deal with these exception fault.

This paper described a dual-band PA with MEMS capacity switch, and it is composed of the series MEMS capacity switch, cascode amplifier and other circuit, and gets the dual-band of 2.1GHz /2.3GHz PA by the switch capacity variation. The first, a MEMS capacity switch is designed, analyzed by EDA of HFSS, and obtain the capacitive curve with 2.1GHz and 2.3GHz, insert loss is about 2dB and isolation is about 50dB.The second, the MEMS switch is applied in the PA circuit, and the circuit model is designed basing on the CMOS technology. The performance is obtained by EDA of ADS simulation, and the gain is 12.4dB and 11.5dB with 2.1GHz and 2.3GHz and PAE is about 50% when output 25dBm at two band. MEMS switches are used to implement a variable filter and matching network that allows the PA to realize the dual-band and high efficiency. It has good performance, and it may be applied for mobile communications systems, such as 3.5G (Generation), 4G mobile communications systems.

Novel MEMS (micro-electric-mechanical-system) SAW (surface acoustic wave) is designed in tins paper, and it is manufactured by CMOS, it is easy to integrate other components for SOC (system on chip). The filter is realized by CPW (coplanar waveguide) cavity and BAR (bulk acoustic resonator), and then the equal circuit model is analyzed, the parameters of circuit model is extracted by ADS (advanced design systems) software. The performance of filter is analyzed by HFSS software, and it center frequency is 2.2 GHz, 3 dB band is 200 MHz. The test model is analyzed by equal CMOS circuit, and the performance of models achieved by network Analyzer; center frequency of 2.28 GHz, 3 dB band of 100 MHz, band stop more than 20 dB, and scale of 3.5times2.0 mm2. The filter is satisfied with the requirement of Wimax communications systems, and it has micro scale, easily integrating. If these design physical parameters are changed, the different performances of filters are obtained, and the design has theory and application value.

This paper describes a dual-band 1.95 and 2.14 GHz microstrip patch antenna on synthesize substrate using the complex cavity structure, and the antenna is fabricated with ideal MEMS technology. The antenna is composed of four patch arms with two switches which is connected the patch arms, when the switch is on, the antenna become a frequency, and off is other frequency. The design antenna performance is obtained using the 3D electromagnetic simulator HFSS9.1. The design switch insert loss is better than ?1dB and the antenna return loss is better than ?26dB over entire frequency band 0~10GHz by the HFSS9.1, too. The antenna return loss is ?13.32dB and 21.67dB, at the lower and upper frequencies, respectively. The 3dB band is about 0.5GHz at tow frequencies. The antenna radiation efficiency is 89% and the directivity is 2dB at the lower band, and the 96% and 3dB at the higher one. These results are satisfied with the 3GPP (3rd generation partnership project) WCDMA specifications.