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1.
《Mechatronics》2022
A large-scale high-precision scan stage is important equipment in the industrial productions of micro-fabrication such as flat panel display (FPD) lithography systems. Designing controllers for multi-input multi-output (MIMO) systems is time-consuming and needs experience because of the interaction between each axis and many controller tuning parameters. The aim of this study is to develop a peak filter design method based on frequency response data to reduce repetitive disturbance. This data-based approach does not use the model and only uses the frequency response data of the controlled system and the disturbance spectrum calculated from the scanning error data (Contribution 1). The peak filter is designed by convex optimization and satisfies robust stability conditions for six-degree-of-freedom systems (Contribution 2). The control performance of the designed peak filter is experimentally demonstrated with an industrial MIMO large-scale high-precision scan stage in reducing the scanning error of the main stroke of the translation along the -axis (Contribution 3). 相似文献
2.
《Journal of dairy science》2022,105(12):9623-9638
A simulation study was conducted to examine accuracy of estimating daily O2 consumption, CO2 and CH4 emissions, and heat production (HP) using a spot sampling technique and to determine optimal spot sampling frequency (FQ). Data were obtained from 3 experiments where daily O2 consumption, emissions of CO2 and CH4, and HP were measured using indirect calorimetry (respiration chamber or headbox system). Experiment 1 used 8 beef heifers (ad libitum feeding; gaseous exchanges measured every 30 min over 3 d in respiration chambers); Experiment 2 used 56 lactating Holstein-Friesian cows (restricted feeding; gaseous exchanges measured every 12 min over 3 d in respiration chambers); Experiment 3 used 12 lactating Jersey cows (ad libitum feeding; gaseous exchanges measured every hour for 1 d using headbox style chambers). Within experiment, averages of all measurements (FQALL) and averages of measurements selected at time points with 12, 8, 6, or 4 spot sampling FQ (i.e., sampling every 2, 3, 4, and 6 h in a 24-h cycle, respectively; FQ12, FQ8, FQ6, and FQ4, respectively) were compared. Within study a mixed model was used to compare gaseous exchanges and HP among FQALL, FQ12, FQ8, FQ6, and FQ4, and an interaction of dietary treatment by FQ was examined. A regression model was used to evaluate accuracy of spot sampling within study [i.e., FQALL (observed) vs. FQ12, FQ8, FQ6, or FQ4 (estimated)]. No interaction of diet by FQ was observed for any variables except for CH4 production in experiment 1. No FQ effect was observed for gaseous exchanges and HP except in experiment 2 where CO2 production was less (5,411 vs. 5,563 L/d) for FQ4 compared with FQALL, FQ12, and FQ8. A regression analysis between FQALL and each FQ within study showed that slopes and intercepts became farther from 1 and 0, respectively, for almost all variables as FQ decreased. Most variables for FQ12 and FQ8 had root mean square prediction error (RMSPE) less than 10% of the mean and concordance correlation coefficient (CCC) greater than 0.80, and RMSPE increased and CCC decreased as FQ decreased. When a regression analysis was conducted with combined data from the 3 experiments (mixed model with study as a random effect), results agreed with those from the analysis for the individual studies. Prediction errors increased and CCC decreased as FQ decreased. Generally, all the estimates from FQ12, FQ8, FQ6, and FQ4 had RMSPE less than 10% of the means and CCC greater than 0.90 except for FQ6 and FQ4 for O2 consumption and CH4 production. In conclusion, the spot sampling simulation with 3 indirect calorimetry experiments indicated that FQ of at least 8 samples (every 3 h in a 24-h cycle) was required to estimate daily O2 consumption, CO2 and CH4 production, and HP and to detect changes in those in response to dietary treatments. This sampling FQ may be considered when using techniques that measure spot gas exchanges such as the GreenFeed and face mask systems. 相似文献
3.
《International Journal of Project Management》2022,40(7):798-812
Collaboration can bring multiple benefits to projects. Real collaboration appears, however, complex to implement. So far, there is no scientific agreement on the importance of the formal and relational (behavioural) sides of project collaboration. Through a qualitative study of two collaborating teams in large engineering and construction projects we uncover the roles of these two sides of collaboration and analyse their interplay. We find that relational and formal aspects of collaboration are complementary, yet each has a distinct role. The formal integrative mechanisms provide an arena for relational norms to be established, and for collaborative behaviours to be practiced and implemented. Relational norms transform traditional project management activities into collaborative, integrative ones. We advance theory of collaboration by offering a holistic and at the same time fine-grained view on it, and stress that project teams need to pay equal attention to both formal and relational sides for collaboration to succeed. 相似文献
4.
The aim of this study was to test two different innovative plasma assisted approaches to prolong ricotta shelf life. In one test the ricotta cheese is directly exposed to the plasma effects, and in the other one the plasma is indirectly applied (i.e. blowing the plasma effluents on the substrate). This last approach is innovative and very promising because in this way, plasma treatment can be assured at moments or at places where no plasma source can be used or is available. To the aim, treated and untreated samples were stored at 4 °C for a period of 8 days, during which microbiological, sensory analyses and pH measurements were carried out. Tests were repeated more times to also taken into account product variability. Results highlighted that both treatments in all tests were effective to control microbial proliferation and preserve sensory quality. Specifically, a significant shelf life prolongation was recorded, ranging between 50% and 100%, depending to the type of treatment and on the initial microbial contamination.Industrial relevanceBoth direct and indirect plasma treatments tested have led to a shelf life increase of up 2 days, which is a very promising result for a fresh product such as artisanal ricotta. The current paper offers the first example in literature of “gentle” and efficacious treatment of fresh perishable products by gas effluents plasma-enriched by reactive oxygen or nitrogen species. The easy implementation of the proposed indirect approach and the easily customizable CAP system at room temperature could gain great attention from fresh dairy sector, with economic advantages and benefits also for the environment. 相似文献
5.
6.
Yingmiao Liu Madelon Paauwe Andrew B. Nixon Lukas J.A.C. Hawinkels 《International journal of molecular sciences》2021,22(1)
Approximately 30 years ago, endoglin was identified as a transforming growth factor (TGF)-β coreceptor with a crucial role in developmental biology and tumor angiogenesis. Its selectively high expression on tumor vessels and its correlation with poor survival in cancer patients led to the exploration of endoglin as a therapeutic target for cancer. The endoglin neutralizing antibody TRC105 (Carotuximab®, Tracon Pharmaceuticals (San Diego, CA, USA) was subsequently tested in a wide variety of preclinical cancer models before being tested in phase I-III clinical studies in cancer patients as both a monotherapy and in combination with other chemotherapeutic and anti-angiogenic therapies. The combined data of these studies have revealed new insights into the role of endoglin in angiogenesis and its expression and functional role on other cells in the tumor microenvironment. In this review, we will summarize the preclinical work, clinical trials and biomarker studies of TRC105 and explore what these studies have enabled us to learn and what questions remain unanswered. 相似文献
7.
An understanding of the similar and divergent metrics and methodologies underlying open government data benchmarks can reduce the risks of the potential misinterpretation and misuse of benchmarking outcomes by policymakers, politicians, and researchers. Hence, this study aims to compare the metrics and methodologies used to measure, benchmark, and rank governments' progress in open government data initiatives. Using a critical meta-analysis approach, we compare nine benchmarks with reference to meta-data, meta-methods, and meta-theories. This study finds that both existing open government data benchmarks and academic open data progress models use a great variety of metrics and methodologies, although open data impact is not usually measured. While several benchmarks’ methods have changed over time, and variables measured have been adjusted, we did not identify a similar pattern for academic open data progress models. This study contributes to open data research in three ways: 1) it reveals the strengths and weaknesses of existing open government data benchmarks and academic open data progress models; 2) it reveals that the selected open data benchmarks employ relatively similar measures as the theoretical open data progress models; and 3) it provides an updated overview of the different approaches used to measure open government data initiatives’ progress. Finally, this study offers two practical contributions: 1) it provides the basis for combining the strengths of benchmarks to create more comprehensive approaches for measuring governments’ progress in open data initiatives; and 2) it explains why particular countries are ranked in a certain way. This information is essential for governments and researchers to identify and propose effective measures to improve their open data initiatives. 相似文献
8.
9.
《Information & Management》2021,58(8):103530
We investigate how employees react when confronted with an enterprise system (ES) that does not fit with work processes dictated by local realities. We draw on interview data (n = 31) from a multinational company to reveal how employees devised and coordinated workarounds that were not compliant with corporate IT policy, but enabled the completion of essential activities, thereby creating value for the firm and its customers. The coordination of these workarounds proved essential to their persistence. We discuss both the theoretical implications of our findings regarding workarounds and the practical contributions associated with the idea that non-compliance can be beneficial. 相似文献
10.
《Information & Management》2022,59(1):103571
Product recommendation agents (RAs) assist online firms to adapt their suggested offers to users’ preferences, thereby lowering users’ decision effort. The concept of effort is central in decision-making, yet it remains unclear whether it should be regarded as a cost or as a benefit improving the odds of a better decision. Building on Social Exchange theory, we suggest that interactions between users and RAs are driven by the concepts of perceived interdependence and reciprocity. We suggest that perceived user effort decreases the perceived RA quality, whereas RA effort increases the perceived RA quality. We conducted two experimental studies across different contexts. We found that users evaluate RAs based on their own expended effort, in relation to how much effort they perceived the RA has put into the process of generating recommendations. Such an effect is attenuated by users’ familiarity with the product context. Our findings offer important insights into how online firms can improve the use of their RAs. 相似文献