8,639 research outputs found
Therblig-embedded value stream mapping method for lean energy machining
To improve energy efficiency, extensive studies have focused on the cutting parameters optimization in the machining process. Actually, non-cutting activities (NCA) occur frequently during machining and this is a promising way to save energy through optimizing NCA without changing the cutting parameters. However, it is difficult for the existing methods to accurately determine and reduce the energy wastes (EW) in NCA. To fill this gap, a novel Therblig-embedded Value Stream Mapping (TVSM) method is proposed to improve the energy transparency and clearly show and reduce the EW in NCA. The Future-State-Map (FSM) of TVSM can be built by minimizing non-cutting activities and Therbligs. By implementing the FSM, time and energy efficiencies can be improved without decreasing the machining quality, which is consistent with the goal of lean energy machining. The method is validated by a machining case study, the results show that the total energy is reduced by 7.65%, and the time efficiency of the value-added activities is improved by 8.12% , and the energy efficiency of value-added activities and Therbligs are raised by 4.95% and 1.58%, respectively. This approach can be applied to reduce the EW of NCA, to support designers to design high energy efficiency machining processes during process planning
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Garlic Consumption and All-Cause Mortality among Chinese Oldest-Old Individuals: A Population-Based Cohort Study.
In vitro and in vivo experimental studies have shown garlic has protective effects on the aging process; however, there is no evidence that garlic consumption is associated with all-cause mortality among oldest-old individuals (≥80 years). From 1998 to 2011, 27,437 oldest-old participants (mean age: 92.9 years) were recruited from 23 provinces in China. The frequencies of garlic consumption at baseline and at age 60 were collected. Cox proportional hazards models adjusted for potential covariates were constructed to estimate hazard ratios (HRs) relating garlic consumption to all-cause mortality. Among 92,505 person-years of follow-up from baseline to September 1, 2014, 22,321 participants died. Participants who often (≥5 times/week) or occasionally (1-4 times/week) consumed garlic survived longer than those who rarely (less than once/week) consumed it (p < 0.001). Participants who consumed garlic occasionally or often had a lower risk for mortality than those who rarely consumed garlic at baseline; the adjusted HRs for mortality were 0.92(0.89-0.94) and 0.89(0.85-0.92), respectively. The inverse associations between garlic consumption and all-cause mortality were robust in sensitivity analyses and subgroup analyses. In this study, habitual consumption of garlic was associated with a lower all-cause mortality risk; this advocates further investigation into garlic consumption for promoting longevity
Gene introgression from common wheat into Aegilops L.
AbstractGroup of experiments were carried out to verify possibility of gene introgression from common wheat into Aegilops. The artificial indoor crossbreed was conducted using 7 genotypes from 4 wheat relative species as female, and common wheat as male. The experiment result shows that different species has variable cross ability. Among the 4 Aegilops species, the highest cross rate is from the combination of Aegilops tauschii×Triticum aestivum (46.49% for genotype Ae42, 22.58% for Y92), the second is from Aegilops ovata×T. aestivum (14.76% for Y100, 12.11% for Ae23), the third is from Aegilops cylindrica×T. aestivum (2.23% for Ae7, 8.50% for Y145), and the lowest is from Aegilops speltoides×T. aestivum (0.19%). Hybrid embryos from different combinations have different ability of callus initiation and germination. The hybrid embryos from A. ovata/T. aestivum and Ae. tauschii/T. aestivum have a higher level of callus initiation and germination. Ae. cylindrica/T. aestivum has a middle level, while the Ae. speltoides has a lower level. The interspecific hybrids between Aegilops and common wheat have so low fertility. In back-crosses, the seed-set rate of hybrids of Ae. ovata/T. aestivum is 3.71% and 4.36% respectively back-crossed with male and female parents, while for hybrids of Ae. cylindrica/T. aestivum, they were 0 and 0.33% respectively, and for Ae. tauschii/T. aestivum, 0.33% and 0 respectively. On selfing of the hybrids, the seed-set rate is 0 (no seed set from 9750 florets) for the combination of Ae. cylindrica/T. aestivum, 0.044% (3 selfed seeds out of 6870 florets) for Ae. ovata/T. aestivum and 0 (no seed set from 7253 florets) for Ae. tauschii/T. aestivum. The research suggests that the probability of gene introgression from T. aestivum into Aegilops species is very low in nature
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An Assessment of Health Behavior Peer Effects in Peking University Dormitories: A Randomized Cluster-Assignment Design for Interference
Background: Relatively little is known about the peer influence in health behaviors within university dormitory rooms. Moreover, in China, the problem of unhealthy behaviors among university students has not yet been sufficiently recognized. We thus investigated health behavior peer influence in Peking University dormitories utilizing a randomized cluster-assignment design. Methods: Study design: Cross-sectional in-dormitory survey. Study population: Current students from Peking University Health Science Center from April to June, 2009. Measurement: Self-reported questionnaire on health behaviors: physical activity (including bicycling), dietary intake and tobacco use. Results: Use of bicycle, moderate-intensity exercise, frequency of sweet food and soybean milk intake, frequency of roasted/baked/toasted food intake were behaviors significantly or marginally significantly affected by peer influence. Conclusion: Health behavior peer effects exist within dormitory rooms among university students. This could provide guidance on room assignment, or inform intervention programs. Examining these may demand attention from university administrators and policy makers
Wireless information and energy transfer in multi-cluster MIMO uplink networks through opportunistic interference alignment
In this paper, we consider a K-cluster (K >= 2) simultaneous wireless information and power transfer (SWIPT) network, where S nodes (S >= 2) are selected from N nodes within each cluster for the uplink information transmission (IT) and the remaining N - S idle nodes are dedicated to energy harvesting (EH). Based on the intra-cluster performance aware (ICPA) philosophy, a pair of opportunistic interference alignment (OIA) schemes, namely the coarse ICPA-OIA (C-ICPA-OIA) and the refined ICPA-OIA (R-ICPA-OIA), are proposed for balancing the sum rate performance achieved and the energy harvested. Specifically, the C-ICPA-OIA treats the overall signal strength within the reference signal subspace (RSS) as a coarse description of the node’s effective signal strength. By comparison, to take full advantage of zero-forcing (ZF) based reception, the R-ICPA-OIA considers the projected signal strength with respect to the orthonormal basis of RSS as a substantially refined description of the node’s effective signal strength. Furthermore, we analyzed the harvested power and the working time of the system. Extensive simulation results validate our theoretical analyses, demonstrating that our schemes outperform the existing OIA schemes
Constraining the ellipticity and frequency of binary neutron star remnant via its gravitational-wave and electromagnetic radiations
The nature of the merger remnant of binary neutron star (BNS) remains an open
question. From the theoretical point of view, one possible outcome is a
supra-massive neutron star (SMNS), which is supported by rigid rotation and
through its survival of hundreds of seconds before collapsing into a black hole
(BH). If this is the case, the SMNS can emit continuous gravitational waves
(GW) and electromagnetic (EM) radiation, particularly in the X-ray band. In
this work, the ellipticity and initial frequency of SMNS are constrained with a
Bayesian framework using simulated X-ray and GW signals, which could be
detected by The Transient High Energy Sky and Early Universe Surveyor (THESEUS)
and Einstein Telescope (ET), respectively. We found that only considering the
X-ray emission can not completely constrain the initial frequency and
ellipticity of the SMNS, but it can reduce the ranges of the parameters.
Afterwards, we can use the posterior distribution of the X-ray parameter
estimates as a prior for the GW parameter estimates. It was found that the
95 credible region of the joint X-ray-GW analysis was about times
smaller than that of the X-ray analysis alone.Comment: Accepted by MNRA
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