Identifying Characteristics of the Agile Development Process That Impact User Satisfaction

The purpose of this study is to identify the characteristics of Agile development processes that impact user satisfaction. We used user reviews of OSS smartphone apps and various data from version control systems to examine the relationships, especially time-series correlations, between user satisfaction and development metrics that are expected to be related to user satisfaction. Although no metrics conclusively indicate an improved user satisfaction, motivation of the development team, the ability to set appropriate work units, the appropriateness of work rules, and the improvement of code maintainability should be considered as they are correlated with improved user satisfaction. In contrast, changes in the release frequency and workload are not correlated

A High-Accuracy Ultra-Low-Power Offset-Cancelation On-Off Bandgap Reference for Implantable Medical Electronics

An ultra-low-power and high-accuracy on-off bandgap reference (BGR) is demonstrated in this paper for implantable medical electronics. The proposed BGR shows an average current consumption of 78 nA under 2.8 V supply and an output voltage of 1.17 V with an untrimmed accuracy of 0.69%. The on-off bandgap combined with sample-and-hold switched-RC filter is developed to reduce power consumption and noise. The on-off mechanism allows a relatively higher current in the sample phase to alleviate the process variation of bipolar transistors. To compensate the error caused by operational amplifier offset, the correlated double sampling strategy is adopted in the BGR. The proposed BGR is implemented in 0.35 μm standard CMOS process and occupies a total area of 0.063 mm2. Measurement results show that the circuit works properly in the supply voltage range of 1.8–3.2 V and achieves a line regulation of 0.59 mV/V. When the temperature varies from −20 to 80 °C, an average temperature coefficient of 19.6 ppm/°C is achieved