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Unstaffed retail shops have emerged recently and been noticeably changing our shopping styles. In terms of these shops, the design of vending machine is critical to user shopping experience. The conventional design typically uses weighing sensors incapable of sensing what the customer is taking. In the present study, a smart unstaffed retail shop scheme is proposed based on artificial intelligence and the internet of things, as an attempt to enhance the user shopping experience remarkably. To analyze multiple target features of commodities, the SSD ( $300\times 300$ ) algorithm is employed; the recognition accuracy is further enhanced by adding sub-prediction structure. Using the data set of 18, 000 images in different practical scenarios containing 20 different type of stock keeping units, the comparison experimental results reveal that the proposed SSD ( $300\times 300$ ) model outperforms than the original SSD ( $300\times 300$ ) in goods detection, the mean average precision of the developed method reaches 96.1% on the test dataset, revealing that the system can make up for the deficiency of conventional unmanned container. The practical test shows that the system can meet the requirements of new retail, which greatly increases the customer flow and transaction volume.

Unmanned aerial vehicles (UAVs) have more and more potential in the emergency rescue tasks under disastrous conditions. Thus, the environmental adaptability of UVAs under extreme high and low temperature levels is very important. Firstly, we built an extreme environmental testing chamber that could simulate multiple disaster conditions. Secondly, the performance of the whole machine of UVAs especially the flying performance under extreme temperature (−30–60 °C) was investigated. Thirdly, the electrical performance of lithium-ion battery used in UVAs was investigated at the same time. Main conclusions were: (1) The high temperature condition even 60 °C had little effect on the flying performance, while significantly degraded the lifetime and discharging capacity, and even damaged the lithium-ion battery. (2) The low temperature condition significantly decreased the flying performance and the battery performance. UAV could not work normally when the environmental temperature was below −25 °C. (3) The low-temperature condition played greater effect on the battery performance than that of high-temperature condition and the testing results of battery discharge experiments well explained this phenomenon. (4) The irreversible and the reversible heat took the dominant role for lower and high temperatures, respectively.

A new method for traffic tunnels with large deformations of soft rock is produced based on the research and development of a new yielding anchor and on the successful application of a large deformation tunnel to a coal mine system. Moreover, this new method should adopt the basic principle of timely support, strong support, and yieldable support to maintain a certain supporting resistance to preserve the stability of surrounding rocks and somehow allow displacement for the support system. Therefore, the support system’s functions include supporting, yielding, and unloading. A yielding support system can then be designed according to the basic principle, comprising of parts such as yielding anchor, sprayed concrete, pressure controller, and arch frame. Combinations of the yielding system components and key technical problems for future resolution are proposed by discussing the basic yielding anchor mechanism and analyzing the components of the system and these problems. The main technical problems include deformation coordination and yielding support system stability; determining the relationship and amount of free surrounding rock deformation; surrounding rock and support joint deformations, and constant resistance yielding; setting the initial yielding load scientifically; and maintenance of the constant resistance characteristic of the components. Meanwhile, field test research on the yielding support system should be combined with a suitable project background to further verify the suitability and reliability of the system.

The pneumatic control system for double-cylinder collaborative loading is extensively applied in the industry. However, compared to the hydraulic system, it is difficult for the pneumatic system for double-cylinder collaborative loading to get satisfactory effect due to strong non-linearity and low rigidity. To improve robustness of the double-cylinder collaborative loading system and increase its control precision, the double-looped PID hybrid controller and doublevariable neural network PDI controller are designed. The comparative test is performed for them in research. The research results indicate that the neutral network control is strongly adaptive to the unknown, uncertain and non-linear features of the controlled objects, can effectively overcome unfavorable influences of the non-linear factors on the system, and improve the control quality.

Analysis of heavy metal pollution in sediment is of importance to water treatment. In the present study, borehole columnar sediment samples with 3~4 m thickness from 86 points along Maozhou River were collected to determine the concentrations of six main metal elements (Cu, Cr, Cd, Pb, Zn, Ni) using plasma direct reading spectroscopy. Then, the vertical distribution of heavy metal among sediment is revealed. What’s more, the pollution risk levels at different depths are determined by potential ecological risk index. The heavy metal source is also discussed through correlation analysis between different heavy metal elements. The result of this study provide valuable reference for dredging depth determination as well as treatment of malodorous black water body.

Resource sharing among peers is one of important application in Peer-to-Peer(P2P) network. Inexistence of server makes P2P network to be a less trustable tool for property owners to distribute their resource. In order to protect intelligent property, reputation management strategy is adopted in many P2P network. As long as a P2P network reputation strategy is confirmed, application designer can employ a special detailed distribution scheme to fulfill content distribution within the net. Shmir (k, n) threshold scheme, for example, is an encryption scheme to enhance the distribution security of this kind of design. (k', n) threshold scheme is a new tool similar to Shmir scheme is proposed in this paper. The new scheme based on polynomial expansion and its security is decided by the one way function used in the secret distribution procedure. The scheme efficiency and its features as well as comparison between new and Shmir scheme are also discussed in this paper.

Smart distribution grid is the important part of smart grid which connects the main network with users. It is directly user oriented and the center of power distribution. This article has compared the smart distribution grid with regular traditional distribution network. Crucial techniques including automation technology, Informationization technology and interaction are the emphasis of discussion. The results have indicated that researches on advanced electric equipment, online monitoring, self healing, advanced metering infrastructure, integrated communication, micro gird and other technologies would be the principal directions of study on smart distribution grid, simultaneously providing reference for realization of practical application in future. KeywordsSmart distribution grid; Automation technology; Informationization technology; Interaction technology

OBJECTIVE: To produce a new bone tissue engineered carrier through combination of xenograft bone (X) and sodium alginate (A) and to investigate the biological character of the cells in the carrier and the ability of bone-forming in vivo, so as to provide experimental evidence for a more effective carrier. METHODS: BMSCs were extracted from 2-week-old New Zealand rabbits and the BMSCs were induced by rhBMP-2 (1 x 10(-8)mol/L). The second generation of the induced BMSCs was combined with 1% (V/W) A by final concentration of 1 x 10(5)/mL. After 4-day culture, cells in gel were investigated by HE staining. The second generation of the induced BMSCs was divided into the DMEM gel group and the DMEM containing 1% A group. They were seeded into 48 well-cultivated cell clusters by final concentration of 1 x 10(5)/mL. Seven days later, the BMP-2 expressions of BMSCs in A and in commonly-cultivated cells were compared. The second generation of the induced BMSCs was mixed with 2% A DMEM at a final concentration of 1 x 10(10)/mL. Then it was compounded with the no antigen X under negative pressure. After 4 days, cells growth was observed under SEM. Twenty-four nude mice were randomly divided into 2 groups (n = 12). The compound of BMSCs-A-X (experimental group) and BMSCs-X (control group) with BMSCs whose final concentration was 1 x 10(10)/mL was implanted in muscles of nude mice. Bone formation of the compound was histologically evaluated by Image Analysis System 2 and 4 weeks after the operation, respectively. RESULTS: Cells suspended in A and grew plump. Cell division and nuclear fission were found. Under the microscope, normal proliferation, many forming processes, larger nucleus, clear nucleolus and more nuclear fission could be seen. BMP-2 expression in the DMEM gel group was 44.10% +/- 3.02% and in the DMEM containing 1% A group was 42.40% +/- 4.83%. There was no statistically significant difference between the two groups (P > 0.05). A was compounded evenly in the micropore of X and cells suspended in A 3-dimensionally with matrix secretion. At 2 weeks after the implantation, according to Image Analysis System, the compound of BMSCs-A-X was 5.26% +/- 0.24% of the total area and the cartilage-like tissue was 7.31% +/- 0.32% in the experimental group; the compound of BMSCs-X was 2.16% +/- 0.22% of the total area and the cartilage-like tissue was 2.31% +/- 0.21% in the control group. There was statistically significant difference between the two groups (P < 0.05). At 4 weeks after the operation, the compound of BMSCs-A-X was 7.26% +/- 0.26% of the total area and the cartilage-like tissue was 9.31% +/- 0.31% in the experimental group; the compound of BMSCs-X was 2.26% +/- 0.28% of the total area and the cartilage-like tissue was 3.31% +/- 0.26% in the control group. There was statistically significant difference between the two groups (P < 0.05). CONCLUSION: The new carrier compounding A and no antigen X conforms to the superstructural principle of tissue engineering, with maximum cells load. BMSCs behave well in the compound carrier with efficient bone formation in vivo.

The problem of decentralized output feedback adaptive stabilization for a class of large-scale systems subject to uncertain parameters and multiple time-varying delays in the interconnections. The interconnections are assumed to satisfy the matching conditions and the nominal system of each subsystems is strictly feedback positive real. By estimating the unknown bounds of the uncertain parameter matrices we propose a decentralized output feedback adaptive controller, which can guarantee the closed-loop system to converge, globally, uniformly and exponentially, to a bounded ball. Finally, an illustrative example is given to demonstrate the validity of the results.

This paper presents a method of calculating energy losses in distribution systems based on RBF network. For representational samples of reflecting the relation between energy losses and characteristic parameters of distribution net, RBF network with strong regression characteristic is adopted to map complex non-linearly relation between energy losses and characteristic parameters of distribution net, the trend of energy losses varying with distribution net structure and operation parameters is memorized accurately. Meanwhile this paper proposes an optimal clustering criterion of being used to determine the number of nodes of hidden layer, and therefore the use efficiency of the RBF network is improved. In addition, there are some special samples which are difficult to be attracted strongly by network, so the computational error of energy losses for these lines is larger than others. This paper proposes a mechanism of reconstructing network to enhance the precision for samples with larger error by using the fuzzy processing. The distribution net with 68 lines is used as an example, the simulation results have verified that the way presented in this paper has the advantages of simple model, speedy learning and high precision

Radial basis function (RBF) neural networks (NNs) have been used in pattern recognition. The application of RBF network for fault diagnosis in high voltage transmission lines is presented in this paper. A self-adaptive clustering algorithm is proposed for the clustering process of RBFNN. The results of the simulation and fault tolerance test confirm that the proposed method can diagnose the fault of high voltage transmission lines quickly and correctly. Furthermore, it has the fault-tolerant ability that can identify the distorted input signals caused by the disturbance, and therefore it has the practical application value for real-timing information processing system

Objective Renal denervation by radiofrenquency (RF) catheter could result in a significant lowering of blood pressure (BP). This study aims to examine the feasibility and safety of renal denvervation by a standard electrophysiology (EP) catheter and trans-brachial approach for Chinese patients suffered from resistant hypertension. Methods From August 2011 to December 2011, a total of 17 resistant hypertension patients received percutaneous renal artery ablation by a standard RF catheter (Celsius ® , Innercool Therapies, Inc, Johnson&Johnson, USA). Patients were divided into trans-brachial group or trans-femoral group by the operator’s desire and followed up for 3 month after the index procedure. Blood samples were taken to evaluate the effects on renal function. Results There is no difference of BP decrease (systolic BP: 41.8 ± 37.0 mmHg in trans-brachial group vs. 21.4 ± 16.6 mmHg in trans-brachial artery group, p = 0.172; diastolic BP: 23.1 ± 24.4 mmHg vs. 14.9 ± 13.2 mmHg, p = 0.396) between the 2 groups. The trans-brachial group has a tendency of longer procedure time (117.2 ± 36.0 min vs. 89.4 ± 16.4 min, p = 0.063) and fluoroscopy time (26.8 ± 7.9 min vs. 20.1 ± 4.8 min, p = 0.057) comparing with trans-femoral group. The renal function presented by eGFR didn’t change (118.8 ± 101.0 ml/min/1.73m 2 vs. 85.4 ± 48.4 ml/min/1.73m 2 , p = 0.29). Conclusions Catheter-based renal denervation by a standard EP catheter seems an attractive novel minimally invasive treatment option in patients with resistant hypertension, and trans-brachial approach is also feasible for this new promising therapy.

Objective To investigate and compare the pattern of instent neointimal formation and native atherosclerosis in the coronary bifurcation lesions by volumetric analysis using systematic intravascular ultrasound (IVUS). Methods This study examined 102 native coronary artery bifurcation lesions and 51 post-stenting bifurcation lesions treated with drug-eluting stents using the T-stenting technique at 9-month follow-up IVUS images for both main vessel and side branch. Three interested segments were analysed: proximal main vessel (MVp) ostium, distal main vessel (MVd) and side branch ostium (SBo). At each segment, four quadrant analysis was performed per 1 mm by measuring the vessel area (stent area in the post-stenting lesions), lumen area and calculating the plaque area for volumetric analysis. Results In the plaque group, the plaque volume differed significantly between the four quadrants (P When the left main (LM) bifurcation (n = 38) was analysed separately, the abcarinal quadrant still had the largest plaque volume and the carinal quadrant the least in all three segments, while the epicardial and myocardial quadrant did not differ in the MVp (P = 0.99). In the MVd and SBo, the plaque volume of myocardial quadrant was still significantly greater than the epicardial quadrant (P In the neointima group, the neointimal volume differed significantly in the MVp and MVd (P = 0.002, P = 0.002, separately), while the four quadrants did not differ in the SB (P = 0.281). In the MVp and MVd, the neointimal volume was larger in the abcarinal than the carinal quadrant (in MVp, 4.8 mm3 [IQR 2.7.6.3 mm3] vs.2.1 mm3 [IQR 0.5.3.9 mm3], P When comparing the eccentricity indices between plaque and neointima groups, there was no difference in the MVp, while the neointima group was significantly smaller than plaque group in the MVd (1.6 [IQR 0.8, 2.8] vs. 4.7 [IQR 2.1, 8.7], P Conclusions The distribution of neointimal proliferation and seems to have a similar pattern to that of atherosclerotic plaque in native coronary arteries, particularly in the main vessel, but the trend is less prominent.