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ABSTRACT: Globally, China is one of the primary citrus producers. This study provided a theoretical reference for sustainable production in the citrus industry in China by measuring citrus production efficiency under non-point source pollution and analyzing inter-provincial variability. In this study, non-radio logical and non-angled data envelopment analysis models were used in seven provinces during 2006-2018 based on non-desired outputs. The temporal and spatial characteristics were analyzed to determine the factors that cause efficiency losses. Results indicated that the citrus production efficiency had a general w-type trend with high inter-provincial variability, where the highest and lowest production efficiencies occurred in Hubei Province and Guangdong Province, respectively. In the past four years, a redundancy in labor and fertilizer inputs was also observed in Guangdong and Fujian, respectively. The shrinkable proportion of each factor input in the seven provinces was zero. An increase in citrus yield per hectare was recorded, in which the highest was in Guangdong. In each province, high emissions of total nitrogen and phosphorus generally caused the decrease in citrus production efficiency.

Augmented reality (AR) has been incorporated into the educational context for years. Numerous studies have demonstrated the effectiveness of AR in different disciplines, learning styles, and learning environments. However, few studies have focused on the problem of generating AR applications in authentic educational contexts. In this study, an AR learning resource authoring tool called WebART was designed and developed to help teachers with no prior programming experience create and share AR learning resources. This study collected feedback and opinions on WebART from 51 K-12 teachers through questionnaires and interviews. Multiple linear regression was used to measure the relationships between teachers' intentions to use technology and the user experience of the proposed WebART tool. The questionnaire results revealed that multiple variables in teachers' intentions are predictive of user experience. Interview results showed that teachers had a positive attitude toward the AR learning resources authoring tools inspiring novel ways of teaching and learning.

The advent of Network Function Virtualization (NFV) technology has brought flexible provisioning to Fog–Cloud Computing-based Networks (FCCNs) for enterprises to outsource their network functions to data center networks. Service Function Chaining (SFC) is a networking concept in NFV by which traffic is steered through an ordered set of Virtual Network Functions (VNFs) composing an end-to-end service. When hundreds of users outsource their network functions to FCCN, the optimal placement of VNFs in the network becomes important for assembling SFCs with the aim of resource utilization efficiency. Motivated by the scalability shortcomings of existing schemes, we propose Deep Reinforcement Learning (DRL)-based approaches by simultaneously considering parallelized SFC and reuse of VNFs to solve this problem, i.e., Asynchronous Advantage Actor–Critic (A3C). A parallelized SFC consists of several sub-SFCs, which can reduce delay and guarantee availability. Also, reuse of preliminary VNFs in SFC placement can improve computation acceleration. The proposed scheme pursues the maximization of the long-term cumulative reward for the trade-off between Quality of Service (QoS) and service cost. The results of the experiments show that the proposed scheme performs better than the state-of-the-art methods.

This study aims to explore the impact of an augmented reality (AR) scientific inquiry tool based on a brain-computer interface (BCI) on students' scientific performance, flow experience, self-efficacy, and cognitive load of primary school students. The BCI-based AR inquiring tool provides real-time attention feedback to students' activities in an AR science learning environment. Before the formal experiment, a pilot study was conducted to prove that the attention estimation algorithm involved in the tool is effective and the AR learning environment based on the BCI technology is feasible. In the formal study, quantitative and qualitative data were analyzed. A total of 41 primary school students were randomly assigned to the experimental group (EG) or the control group (CG) to learn the lever principle. The students of EG used the BCI-based AR inquiring tool, and the CG used simple AR inquiring tools without real-time attention feedback. Results show that the BCI-based AR inquiring tool positively impacts students' scientific inquiry. It significantly helps students improve their science learning performance, achieve mental flow, and promote their scientific inquiry participation self-efficacy. Besides, no significant effect on cognitive load was found. The interview results indicate that students have a positive attitude toward the BCI-based AR scientific inquiry tool.

The Augmented Reality (AR)-based learning environment not only provides educators with novel ways to present learning materials but also give learners the opportunity to spontaneously interact with the material. Previous studies have shown that AR has many advantages in education; however, few focuses on the mechanisms behind promoting inquiry motivation, such as the effect of AR on learners' self-efficacy and conceptions of learning. This study developed an AR-based wave-particle duality learning application, "AROSE," to explore the effect of AR technology on students' self-efficacy and conceptions of learning physics. A quasi-experimental study method was used, and 98 high school students aged between 16 and 18 were randomly assigned to experimental and control group. After a 4-week intervention, it was found that integrating AR technology into physics classrooms can (1) significantly enhance students' physics learning self-efficacy, as indicated by understanding of concepts, higher-level cognitive skills, practice and communication; (2) guide students to be more inclined to higher-level conceptions of learning physics rather than lower ones; and (3) stimulates students' motivation to learn more deeply.

Aluminum is a widely distributed element and plays an indispensable role in our lives, but excessive intake of Al3+ can cause potential harm to human health. Highly selective methods for the rapid detection of Al3+ are urgently needed. Here, a novel "turn on" fluorescent probe L based on Schiff-base of 2-hydroxy-1-naphthaldehyde and 8-aminoquinoline was obtained in an excellent yield. Probe L presents significant properties such as rapid response, good stability, wide pH range, simple synthetic operation, and provides an efficient strategy for the highly selective detection of Al3+ in an aqueous solution of DMSO/H2O (7:3, v:v). According to Job's curve and fluorescence titration, probe L with Al3+ forms a 2:1 ratio of complex, and the lowest limit of detection is 3.23 × 10−8 mol/L. The possible combination mode for probe L with Al3+ was proposed by comparison with the changes of 1H NMR and FTIR spectra of L and its complex. In addition, the potent applicants for probe L were also investigated, and indicated that it could conveniently be made into a series of sensor strips and applied to rapidly detect trace Al3+ in traditional Chinese medicine. [ABSTRACT FROM AUTHOR]

This paper compared the effectiveness and efficiency of using computer-assisted instruction (CAI) and teacher-implemented instruction (TII) to teach visual matching skills to students with autism spectrum disorder and/or other developmental disabilities. Four school-aged students participated in this study with an alternating treatment design. The CAI incorporated discrete trial instruction with the gesture-tracking application, while the TII involved traditional one-to-one instruction using flashcards. The results indicated that all students acquired the target matching skills with generalization to similar untaught skills and maintained acquired skills at a high level for up to 5 weeks under both CAI and TII. Both CAI and TII were effective. However, CAI was more efficient than TII in regards to the prompts provided and the duration of instructional sessions. CAI also resulted in more student engagement in independent learning.

The development of Augmented Reality technologies has enabled students to learn in an environment that combines learning resources from the real and digital world. This paper integrates three mobile Augmented Reality-based applications into a series of mathematics lessons on probabilities in a junior high school. This paper aims to examine how mobile AR-based learning applications affect students' learning gains through ANCOVA. Moreover, students' attitudes towards the applications are discussed. The participants are 68 junior high school students. The experimental results show that the mobile AR-based applications would be helpful for students' learning gains in the topic of probability. Students' attitude towards the AR applications in this series of lessons was positive. Overall, it was found that mobile AR-based learning applications have positive effects on junior high students learning mathematics.

Most studies of Augmented Reality (AR) in education have considered students' learning outcomes and motivation. Previous studies have revealed that AR has the potential to help students learn abstract conceptions in mathematics. In this paper, a series of statistics and probability lessons using AR installed on tablets was designed and developed to examine the effect of the AR technology by comparing the conceptions and learning approaches of junior high school students with different levels of self-efficacy. A total of 101 students were divided into two groups based on their mathematics learning self-efficacy. The analysis of the results shows that AR applications in mathematics courses can help students with higher self-efficacy to pay closer attention to higher level conceptions. It can also help higher self-efficacy students to apply more advanced strategies when learning mathematics.

This paper compared the effectiveness and efficiency of using computer-assisted instruction (CAI) and teacher-implemented instruction (TII) to teach visual matching skills to students with autism spectrum disorder and/or other developmental disabilities. Four school-aged students participated in this study with an alternating treatment design. The CAI incorporated discrete trial instruction with the gesture-tracking application, while the TII involved traditional one-to-one instruction using flashcards. The results indicated that all students acquired the target matching skills with generalization to similar untaught skills and maintained acquired skills at a high level for up to 5 weeks under both CAI and TII. Both CAI and TII were effective. However, CAI was more efficient than TII in regards to the prompts provided and the duration of instructional sessions. CAI also resulted in more student engagement in independent learning., Author(s): Xiaoyi Hu [sup.1] , Gabrielle T. Lee [sup.2] , Yu-Ting Tsai [sup.3] , Yang Yang [sup.4] [sup.5] , Su Cai [sup.6] [sup.7] Author Affiliations: (1) grid.20513.35, 0000 0004 1789 [...]

Children with Autism Spectrum Disorder (ASD) perform poorly in complex fine motor skills and recognition, and they have difficulties in learning complex and multistep motor skills. Gestures-based games, which enable users to get timely feedback, to learn from failure, to engage in games at every moment, and to interact with computers intuitively have become promising tools. However, relevant empirical research on using gesture-based games to assist the learning of children with ASD is limited. With a case study method, we aim to examine the effects of using gesture-based games on the learning of children with ASD. Two gesture-based matching games were developed to improve the performance of children with ASD with respect to fine motor skills and recognition, and three young children with ASD participated in a three-week experiment. By comparing the participants' performance before and after the treatment, we found that the participants' performance in playing the gesture-based games improved greatly during the intervention, and intervention helped improve their performance regarding fine motor skills and recognition. Also, they were able to transfer the rules and skills they had learnt from the first game to completing the tasks in the second game. The findings above suggest the usefulness of using gesture-based games in assisting the learning of children with ASD. Some suggestions and implications for the development of the gesture-based games and future work are also discussed.

Building an information-based rural economic supply chain is an effective way to implement the rural revitalization strategy. The construction of China’s agricultural product logistics market is still very backward, mainly including imperfect information system and high cost of intermediate circulation links. How to optimize the supply chain of agricultural products, ensure the normal supply of agricultural products quality and quantity in the market, improve people’s living standards, and achieve the purpose of improving benefits is an important topic to be studied today. Aiming at the problems of traditional agricultural products supply chain, the application of Internet of Things technology in supply chain can be effectively solved. Therefore, this paper proposes the research on the environmental effect evaluation of rural economic supply chain based on Internet of Things technology and proposes to build a wireless sensor network for agricultural products for the collection and exchange of agricultural products information. At the same time, RFID (radio-frequency identification) electronic tags integrated with sensors are applied in other links of the supply chain. The experimental results show that the construction of the rural economic supply chain system based on Internet of Things technology can effectively optimize the rural economic supply chain, realize efficient information sharing, improve the quality of agricultural products, reduce the cost of each link of the supply chain, improve the competitiveness of rural supply chain, and promote the good development of rural agricultural products and rural economic supply chain environment.

Educators must address several challenges inherent to the instruction of scientific disciplines such as physics -- expensive or insufficient laboratory equipment, equipment error, difficulty in simulating certain experimental conditions. Augmented reality (AR) can be a promising approach to address these challenges. In this paper, we discuss the design and implementation of an AR and motion-sensing learning technology that teaches magnetic fields in a junior high school physics course. The purpose of this study is to explore the effects of using natural interaction on students' physics learning and deep understanding compared to traditional learning tools. The 38 eighth graders who participated in this study were assigned to either an experimental group or a control group. Analysis of the results shows that the AR-based motion-sensing software can improve students' learning attitude and learning outcome. This study provides a case for the application of AR technology in secondary physics education.

AIM:To evaluate the effect of monocular rectus surgery for adult sensory exotropia. METHODS: Totally 76 cases of adult sensory exotropia of degree -15△ to -160△(-68.36△±30.77△)examined through Krimsky method were included into this study. A total of 16 cases, 37 cases and 23 cases with different degrees of strabismus were treated separately with routine amount monocular lateral rectus recession, routine amount monocular medial rectus resection plus lateral rectus recession, and exceed constant amount monocular medial rectus resection plus lateral rectus recession. Follow-up was performed at 1d, 1wk, 1, 3 and 6mo after operation. The eye position, monocular movement, intraocular pressure(IOP), slit lamp, and fundus of these patients were examined. RESULTS:After surgery, 67 cases(88%)were positive and 9 cases(12%)were undercorrection. The postoperative intraocular pressure of operative eye at 1wk was equal to preoperative(P=0.090), and IOP decreased to a valley value at 1mo(PP=0.092), and no significant difference in intraocular pressure between 6mo and 3mo(P=0.123). And 2 cases(3%)had inflammatory reaction induced by anterior segment ischemia at 1d and 1wk postoperative visits, and they recovered at 1mo follow-up visit; 4 cases(5%)experienced an external dysfunction at the 1, 3 and 6mo follow-up. CONCLUSION:Monocular rectus surgery has a good therapeutic effect on adult patients with sensory exotropia; the decrease in intraocular pressure secondary to the detached rectus is worth the attention of the surgeon; the incidence of complications after detaching monocular of two rectus muscles is comparable low. Exceed constant amount rectus strabismus surgery for sensory exotropia may result in limited function of postoperative ocular hyperextension.

To study the dynamic properties of intermediate strain rates for filiform or filmy materials, a miniature tensile-test system with an intermediate strain rate based on magnetic resistance actuation is designed herein. The loading part of the system is formed by inertial movement and an electromagnetic launcher, and the testing part is formed by high-speed optical noncontact measurements using a microforce sensor. Constant tension and intermediate speed are realized by designing the inertial motion of a large-mass combined accelerator. Friction and vibration are offset using magnetic attraction. The electromagnetic acceleration force was eliminated by adjusting the length differences, construction, and relative motion of the structures. The stress–strain curves are obtained by synchronizing the strain signal measured using the optical extensometer method and the stress signal measured using the microforce sensor. The system is verified to be miniature, stable, easy to control, accurate for strain rate, economic, and used for small samples. The stability and reliability of the system are verified using speed testing and motion-state photography. Therefore, the designed system is miniature, easy to control, highly cost-effective, and can be used for filiform or filmy samples. [ABSTRACT FROM AUTHOR]

AIM: To observe the image difference of dimensional CT monocular superior oblique palsy form the patient's eyes.METHODS: Clinical cross-sectional study included of 30 cases which clinically diagnosed monocular congenital superior oblique palsy for dimensional CT. CT values were measured at the position of coronal oblique maximum cross-sectional area at patient eyes.RESULTS: Ocular and non-ocular paralysis of superior oblique muscle belly maximum cross-sectional area were 4.52±1.49, 8.80±1.42mm2,respectively. CT values were 11.57±22.88 and 35.13±9.74. Paralysis of eye muscles abdominal oblique maximum cross-sectional area and CT values were significantly less than those of the non-paralyzed eye. The difference had statistical significance.CONCLUSION: The results of dimensional CT scan shows that the CT value of patients with monocular congenital superior oblique palsy superior oblique eye muscle paralysis abdominal cross-sectional area is significantly higher than that of the non-paralyzed eye on the oblique abdominal muscle cross-sectional area.