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Technological-Personal-Environmental (TPE) Framework: A Conceptual Model for Technology Acceptance at the Individual Level
This paper describes the development of the Technological-Personal-Environmental (TPE) framework, which explains individuals’ behaviors of technology acceptance. We argue that existing individual-level technology acceptance theories provide a valuable, but incomplete, understanding of individuals’ technology acceptance. By synthesizing extant technology acceptance models and theories, the proposed TPE delineates the individual-level technology acceptance from technological, personal, and environmental aspects. The proposed framework provides a wider angle to investigate individual-level technology acceptance
Modelling centrifugal membrane deployment of solar sails with the discrete element method
Spin-stabilized solar sails have been extensively studied in recent years. In this paper, a DEM-based approach is proposed for dynamic analysis of the centrifugal deployment of solar sails. In order to validate the proposed approach, the deployment of a small-scale solar sail similar to “IKAROS” is studied. The membrane is discretised into a number of particles, with no physical contact between them. Non-contact interaction is introduced to model in-plane stiffness of the membrane. In order to improve the accuracy, additional forces are applied to the mass particles to model buckling strength, crease stiffness, air drag and damping. The predicted results of the membrane deployment are compared with the experimental data and numerical results in the literature
An Investment Analysis for China\u27s Sustainable Development Based on Inverse Data Envelopment Analysis
In the face of environmental degradation, sustainable development has become a common goal across the globe. Making a scientifically based investment scheme is of great significance to promote the sustainable development of China\u27s economy. However, there is scarce research related to such an investment scheme of sustainable development. This paper proposes a new inverse data envelopment analysis method with undesirable outputs to make several scientifically based investment schemes from different perspectives, namely, the natural, regulation, and optimal perspectives. By this method, decision makers can scientifically forecast the specific amount of investment based on their actual sustainable development objectives, which is conducive for reducing the blindness of investment in the future. In addition, a new ideal perspective is defined to guide a definite direction for improving the level of sustainable development. Combined with the gray forecasting model GM(1,1), the methods proposed by this paper were then applied to analyze the investment problem for China\u27s sustainable development during the 2015–2024 period. The results show that: the unbalanced distribution of labor investment and the excessive investment in capital and energy are serious barriers to China\u27s sustainable development in the short term; and in the long term, the demand for investment in labor and capital will continue to increase along with a lower demand for energy investment, and that appropriately strengthening environmental regulations will not affect the overall demand for investment. Meanwhile, improvement directions for improving China\u27s sustainable development are discussed, and the results show that most of developing and undeveloped regions in China have great potential for improvement. Finally, some suggestions are proposed in order to create better conditions for China\u27s sustainable development
Theoretical and experimental studies on the oil-based emulsion spray
Oil-based emulsion is a common herbicide formulation in agricultural spray, and its atomization mechanism is different from that of water spray. In this paper, a theoretical model based on the characteristics of spray sheets was proposed to predict the spray droplet size for oil-based emulsion spray. An image processing method was used to measure droplet size distributions for different spray pressures and nozzle configurations, and the measured results were used to validate the theoretical model. The results show that oil-based emulsion spray is characterized by the web structure constituted by perforations. The liquid originally occupied by spray sheets eventually gathers in these web structures. The proposed theoretical model is based on the size of the nozzle exit, the angle of spray sheets, and the perforation number in the web structure, which are relatively easy to obtain. The theoretical droplet size is in inverse proportion to the square root of the perforation number in the web structure while in proportion to the square root of the area of the nozzle exit. The captured images of spray sheets and the measured droplet size distribution show consistency with the theoretical prediction. The difference between theoretical results and measured volumetric median diameter is less than 10% for different spray pressures and nozzles
Achieving Covert Communication With A Probabilistic Jamming Strategy
In this work, we consider a covert communication scenario, where a
transmitter Alice communicates to a receiver Bob with the aid of a
probabilistic and uninformed jammer against an adversary warden's detection.
The transmission status and power of the jammer are random and follow some
priori probabilities. We first analyze the warden's detection performance as a
function of the jammer's transmission probability, transmit power distribution,
and Alice's transmit power. We then maximize the covert throughput from Alice
to Bob subject to a covertness constraint, by designing the covert
communication strategies from three different perspectives: Alice's
perspective, the jammer's perspective, and the global perspective. Our analysis
reveals that the minimum jamming power should not always be zero in the
probabilistic jamming strategy, which is different from that in the continuous
jamming strategy presented in the literature. In addition, we prove that the
minimum jamming power should be the same as Alice's covert transmit power,
depending on the covertness and average jamming power constraints. Furthermore,
our results show that the probabilistic jamming can outperform the continuous
jamming in terms of achieving a higher covert throughput under the same
covertness and average jamming power constraints
The molecular clouds in a section of the third Galactic quadrant: observational properties and chemical abundance ratio between CO and its isotopologues
We compare the observational properties between CO, CO, and
CO and summarize the observational parameters based on 7069 clouds
sample from the Milky Way Imaging Scroll Painting (MWISP) CO survey in a
section of the third Galactic quadrant. We find that the CO angular area
() generally increases with that of CO (), and the ratio of to is 0.38 by
linear fitting. We find that the CO and CO flux are tightly
correlated as with both fluxes
calculated within the CO-bright region. This indicates that the
abundance is a constant to be 6.5 for all samples under assumption of local thermodynamic equilibrium
(LTE). Additionally, we observed that the X-factor is approximately constant in
large sample molecular clouds. Similarly, we find with both fluxes calculated within
CO-bright region, which indicates that the abundance ratios stays the same value 9.7 across the
molecular clouds under LTE assumption. The linear relationships of vs. and vs.
hold not only for the CO-bright region or CO-bright region, but
also for the entire molecular cloud scale with lower flux ratio. The abundance
ratio inside clouds shows a strong
correlation with column density and temperature. This indicates that the
is dominated by a combination of chemical
fractionation, selectively dissociation, and self-shielding effect inside
clouds.Comment: 11 pages, 16 figures, 1 table, accepted by A
CT-guided 125I brachytherapy combined with chemotherapy for the treatment of unresectable or locally advanced pancreatic carcinoma
PURPOSEWe aimed to explore the feasibility and clinical effectiveness of percutaneous CT-guided iodine-125 (¹²⁵I) brachytherapy combined with chemotherapy for the treatment of patients with unresectable or locally advanced pancreatic carcinoma (PC).METHODSWe retrospectively reviewed 66 patients with Stage III and IV PC who had received chemotherapy. A total of 35 (53%) patients receiving 125I brachytherapy and chemotherapy (gemcitabine + cisplatin, GP) were classified as Group A, and 31 (47%) patients who received GP chemotherapy alone were categorized as Group B. The evaluated indications were local control rate (LCR), local progression-free survival (LPFS), overall survival (OS), treatment-related complications, and the degree of symptom relief. Kaplan-Meier curves, log-rank test and Cox regression models were generated and used for further analysis to identify predictors of outcomes.RESULTSThe median follow-up time was 6.00±0.84 months. The 1-, 3-, 6-, 12- and 18-month LCRs for Group A were 100% (35/35), 89.3% (25/28), 71.4% (15/21), 37.5% (3/8) and 33.3% (1/3), respectively; and those for Group B were 87.1% (27/31), 69.6% (16/23), 41.2% (7/17), 14.3% (1/7) and 0% (0/3), respectively. The LCR differed at 1-, 3- and 6-months (P = 0.032; P = 0.009; P = 0.030; respectively). The median LPFS was 7.00±0.30 months and 5.00±0.75 months for Groups A and B (P = 0.023), respectively; however, the median OS of the groups were not significantly different (8.00±0.77 months vs. 6.00±1.04 months. P = 0.917). No life-threatening complications occurred during or after the procedures. Patients in Group A experienced better pain control and relief of abdominal distension than those in Group B.CONCLUSIONCT-guided 125I brachytherapy is a feasible, safe, and valuable treatment for patients with unresectable PC
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