Earticle

This paper describes a 12-bit 100kS/s successive approximation register analog-to-digital converter (SAR ADC) for biomedical system. Both top-plate sampling technique and VCM-based switching technique are applied to the capacitor digital-to-analog converter (CDAC) to implement a 12-bit SAR ADC with 10-b capacitor array DAC. To enhance the linearity of proposed ADC, thermometer decoder is used in capacitor array DAC. Switching-energy minimization technique, asynchronous control with a low-power delay circuit and true single phase clocking (TSPC) D_FF are also adopted to reduce power consumption. Simulation results show that the proposed ADC achieves the SNDR of 70.97dB, the SDFR of 80.23dB and the ENOB of 11.49b with the CMOS 0.18m technology. Total power consumption is 11.16W under the supply voltage of 1.8V at the sampling frequency of 100 kHz. And the figure of merit (FoM) is 38.79fJ/conversion-steps.

Online-to-offline (O2O) commerce is emerging as a global issue as the number of consumers going to and fro from online to offline in search of optimal shopping conditions based on price and convenience rises rapidly. O2O commerce effectively connects online and offline services, thus providing services to consumers with greater convenience. Compared to such remarkable advancement, however, there is a noticeable shortage of research in this field. A review of preceding studies shows that a large part of the research that has been conducted is from the perspective of acceptance or proliferation, which are initial stages in the research of a field. On the contrary, research on the discontinuance intention of consumers already using O2O commerce are highly rare and calls for further research. This study examines consumers’ negative perception of O2O commerce and how this affects discontinuance intention of a service. The data utilized in the research was collected through a survey. It reached a conclusion by conducting an empirical analysis using structural equation methodology and proposed theoretical and practical suggestions.

This study used a non-equivalent control group pre-test post-test design to develop an emergency nursing simulation-based education program for hypoglycemia patients, and examine the program’s effects on nursing students’ self-directed learning ability and confidence in performance of these said activities. Participants included sophomore nursing students from the Department of Nursing at S University in Seoul. Participants were divided in experimental (n=30) and control (n=30) groups. A 1-hour lecture on diabetes was administered to both groups. Subsequently, the experimental group was divided into teams and engaged in self-study for 1 week, after which time they participated in the simulation-based education program. Data were analyzed using SPSS, and the homogeneity of the dependent variables was verified using X3 tests and t-tests. Post-intervention between-group differences in self-directed learning ability and confidence in performance were analyzed using an ANCOVA. Study results showed that there was significant improvement in self-directed learning ability (F=8.49, p=.005) and confidence in performance (F=13.88, p<.001) for the experimental group. Therefore, this simulation-based program may be utilized as a useful educational method for enhancing nursing students’ clinical performance abilities.

This study was purposed to verify the effect of repeated exposure and role to play in simulation-based education on hospital emergency care. 144 nursing students, at Y University in Daegu, Korea, had participated in this non-equivalent control group quasi-experimental study. All participants had 6 time simulation-based educations on hospital emergency care. The experimental group (n=65) had experience as a leader but the control group (n=79) didn’t have. Data were collected from October 01 to December 23 in 2014 regarding problem solving, critical thinking, satisfaction of simulation, performance evaluations by evaluator and students themselves on simulation-based education. It was analyzed with two sample t-test and repeated measured ANOVA using PASW Statistics (SPSS) 21.0 program. Satisfaction (t=0.257, p=.798), self-evaluation (t=-1.650, p=.102), and performance (t=0.147, p=.883) scores between two groups were not significantly different after the educations. Performance scores were significantly increased by the number of the simulation-exposure (F=412.724, p<.001), but not significantly different by the leader experience (F=1.246, p=.266). This study would support that repeated simulation-exposures improved the performance level on hospital emergency care regardless of role of simulation settings.

The purpose of this study is to examine the structural relationship among self-efficacy, social influence, effort expectancy, performance expectancy, and behavioral intention of mobile learning, which is based on the extended technology acceptance model. We performed a study to determine the impacts that social influence, performance expectancy, and effort expectancy have on behavioral intention of mobile learning through self-efficacy. Appropriate measures were developed and tested on 226 university students of Gyeongnam province in South Korea with a cross-sectional questionnaire survey. The path relationship of the research model was analyzed by structural equation modeling (SEM) using AMOS 18.0. The results revealed that firstly, self-efficacy has positive effects on performance expectancy, social influence, and effort expectancy. Second, social influence has positive effects on performance expectancy, behavioral intention, and effort expectancy. Third, effort expectancy has positive effects on performance expectancy and behavioral intention. Fourth, performance expectancy has a positive effect on behavioral intention. Managers of mobile learning should focus on self-efficacy to enhance behavioral intention.

The purpose of this study was to measure post-dialysis fatigue in patients on hemodialysis and identifies clinical variables that are associated with post-dialysis fatigue. The subjects for this study were 103 patients who were receiving chronic hemodialysis in outpatient dialysis clinics in Seoul between April 12th and April 23th, 2010 and consented to participate in the study. The collected data were analyzed by the SPSS WIN 12.0 program. The mean score of fatigue were 63.4, 86.8 and 60.8 before hemodialysis, after hemodialysis and next day, respectively. There was a statistically significant (F=5.16, p<.001). All these indicators but ‘tired’, ‘not energetic’, ‘difficult to move’, ‘would like to lie’ did not significantly differ over time after hemodilaysis. ‘Would like to lie’ was strongest after hemodialysis (F=12.52, p<.001). There were significantly positive correlations between post-dialysis fatigue and weight gain (r=.18, p=.038). There were significantly positive correlations between weight gain and ‘tired’, ‘ difficult to move’, and ‘would like to lie’. There were also significantly positive correlations between post-dialysis fatigue and age (r=.19, p=.035), comorbidities (r=.14, p=.031), post dialysis blood pressure (r=-.17, p =.024), weight change (r=.14, p=.034), and hemoglobin (r=-.27, p=.005). Also, Age, comorbidities post-dialysis blood pressure, weight change, and hemoglobin predicted value accounted for 16.8% of the variance on post-dialysis fatigue (F=13.08, p<.001). It is considered that dialysis providers care to recognize post-dialysis fatigue as an important nursing issue for hemodialysis patients. It is also necessary to develop a nursing intervention for improving their post-dialysis fatigue.

In order to assist in the reverse recovery decision of emergency logistics in sudden natural disasters, this paper conducts the system modeling on the reverse recovery of reusable materials in several disaster areas from the perspective of system dynamics under the principle of rescue satisfaction preference. Through the comprehensive analysis of material demand of disaster areas, the occupancy of resources in reverse recovery and other factors, it establishes the function relation between the recovery frequency and rescue satisfaction, and simulates the system model with the system dynamics software Vensim. Finally, the effectiveness and practicability of the model is proved by an example, based on which the impact of transportation resource change on rescue satisfaction is analyzed. Based on the above research conclusion, this paper provides the decision support and countermeasure for the emergency reverse logistics in China.

The effects of CCTV installation on teachers' job stress and teacher-child interaction showed that teachers had positive ideas for young children's thinking, information provision and evidential data by CCTV installation, but they were under serious job stress for CCTV installation. Especially, the CCTV installation was a factor obstructing free skinship or communication between teachers and young children. Consequently, the CCTV installation has a negative effect on teacher-child interaction, lowering the quality of teacher-child interaction.

The control problem for manipulators is to determine the joint inputs required to case the end-effector execute the commanded motion. The nonminimum phase characteristic of a rigid manipulator makes the design of stable controller that ensures stringent tracking requirements a highly nontrivial and challenging problem. A useful controller in the computed torque family is the gravity controller. To compensate the dynamic parameters, fuzzy logic methodology is used and applied parallel to this method. When the arm is at rest, the only nonzero terms in the dynamic is the gravity. Proposed method can cancels the effects of the terms of gravity. In this case inorder to decrease the error and satteling time, higher gain controller is design and applied to nonlinear system.

This paper reported a double layer cantilever harvester powered for vibration energy. A space layer between the PZT beam and the support silicon beam is existed, leading to the double layer cantilever structure. Such structure can allow the more strain generated by the piezoelectric layer due to the existing of space layer, and the output voltage is further increased. The formula of output voltage is then derived from the piezoelectric effect equation and vibration model. And the formula verifies the relationship of voltage and structure parameter. And the simulation in micrometer lever is used to discuss the relationship. Finally, the prototype is assembled and measured to verify the feature of the device. Experimentally, the 3.8V output voltage and 16.9uW output power is acquired.