Universal Phase Unwrapping for Phase Measuring Profilometry Using Geometry Analysis

Traditionally temporal phase unwrapping for phase measuring profilometry needs to employ the phase computed from unit-frequency patterned images; however, it has recently been reported that two phases with co-prime frequencies can be absolutely unwrapped each other. However, a manually man-made look-up table for two known frequencies has to be used for correctly unwrapping phases. If two co-prime frequencies are changed, the look-up table has to be manually rebuilt. In this paper, a universal phase unwrapping algorithm is proposed to unwrap phase flexibly and automatically. The basis of the proposed algorithm is converting a signal-processing problem into a geometric analysis one. First, we normalize two wrapped phases such that they are of the same needed slope. Second, by using the modular operation, we unify the integer-valued difference of the two normalized phases over each wrapping interval. Third, by analyzing the properties of the uniform difference mathematically, we can automatically build a look-up table to record the corresponding correct orders for all wrapping intervals. Even if the frequencies are changed, the look-up table will be automatically updated for the latest involved frequencies. Finally, with the order information stored in the look-up table, the wrapped phases can be correctly unwrapped. Both simulations and experimental results verify the correctness of the proposed algorithm

Automatic Look-Up Table Based Real-Time Phase Unwrapping for Phase Measuring Profilometry and Optimal Reference Frequency Selection

For temporal phase unwrapping in phase measuring profilometry, it has recently been reported that two phases with co-prime frequencies can be absolutely unwrapped using a look-up table; however, frequency selection and table construction has been performed manually without optimization. In this paper, a universal phase unwrapping method is proposed to unwrap phase flexibly and automatically by using geometric analysis, and thus we can programmatically build a one-dimensional or two-dimensional look-up table for arbitrary two co-prime frequencies to correctly unwrap phases in real time. Moreover, a phase error model related to the defocus effect is derived to figure out an optimal reference frequency co-prime to the principal frequency. Experimental results verify the correctness and computational efficiency of the proposed method

Increasing the Durability of Piezoelectric Impact-based Micro Wind Generator in Real Application

AbstractThe purpose of this study is to increase the durability of piezoelectric impact-based micro wind generator (PIMWG) in real application. Using new PIMWG design, numerical simulation, and experimental comparison analysis, we improved the durability of PIMWGs in real application. The experimental results show that the optimized PIMWG generated 2.4 mW (RMS value), and it did not crack within 40h. In this study, we improved the durability of PIMWGs for real application

Sex- and Age-Related Changes in Connexin 43 Expression in Normal Rat Bladder

Purpose Gap junctions are intercellular channels to facilitate electrical and metabolic communication between adjacent cells. Connexin 43 is the most predominant type of connexin expressed on rat detrusor muscle cells. We investigated the connexin 43 expressions in various age groups of either sex in normal rats. Methods Eighty Sprague-Dawley rats were used for analysis. Each group was quantified by 8 rats at 1 week, 2 weeks, 1 month, 3 months, and 6 months of age in either sex. In each animal, bladder was removed without any kind of intervention and fresh-frozen in liquid nitrogen. Total RNA extraction was done with easy-BLUE total RNA extraction kit. Reverse transcription polymerase chain reaction was done for connexin 43 and glyceraldehyde-3-phosphate dehydrogenase as an internal control using ImProm-II Reverse Transcription System. Results In female rats, no age-related change was detected in connexin 43 expressions. In male rats, connexin expression at 3 months of age showed significant decrease compared with 1 week, 2 weeks, and 6 months of age (P<0.05). When connexin expression at the same age in male and female were compared, only 3 months group in male showed significant decrease than the same age group in female. Conclusions Our data suggest that the expressions of connexin 43 mRNA in normal detrusor muscle cell showed age-related changes especially in male rats. Although it is difficult to interpret these findings at this stage, age should be considered as a possible compounding factor affecting connexin 43 expressions in male rats

Customers’ Continued Adoption of Mobile Apps and Their Satisfaction with Restaurants: The Case of McDonald’s

Background: The major purpose of this research is to examine Contactless Technology (CT) users’ post-adoption phenomena in the context of mobile apps (MA) run by a Quick Service Restaurant (QSR). It applies the Post-Adoption Model of Information System Continuance (PAMISC) to examine how QSR customers’ technology anxiety (TA), confirmation of initial expectations, perceived usefulness (PU), and satisfaction with CT relate to their continued intention of use. Furthermore, the study investigates the relationship between customers’ satisfaction with CT and their overall satisfaction with QSR. Methods: To test the research model, we collected survey data from 245 users of MA provided by McDonald’s restaurants in the US, which are analyzed through Partial Least Square analysis using SmartPLS 4.0. Results: The theoretical relationships in the PAMISC hold true in the context of QSR’s MA. Current QSR customers’ TA is negatively associated with their perceived usefulness, but is not related to the degree of confirmation of using MA. Customers’ continued intention of use and satisfaction with MA are positively related to overall satisfaction with QSR. Conclusion: Our study is among the first to provide empirical/practical evidence of the PAMISC in the context of IT-enabled hospitality services. It also extends the model in two important ways. First, the study examines the role of TA, an important personal trait relevant to individuals’ use of QSR technology. Second, it highlights customers’ satisfaction with firm-provided technology to improve their overall satisfaction with the firm in the context of QSRs. For practitioners, it is important for QSR managers to understand the impact of TA on customers’ adoption of MA, so that they can design their MA with simpler interfaces and more human aspects. Managers should also make sure that MA is well-designed to satisfy customers’ needs, which will then lead to those customers’ overall satisfaction with the QSR