bluuebunny/crossref_metadata_2025 huggingface dataset:
Event‐triggered control for adaptive bilateral teleoperators with communication delays
Authors: Hu Shin‐Chen , Liu Yen‐Chen
Published: November 2019

Bilateral teleoperation systems have been widely applied for human operators to manipulate slave robots in accomplishing various tasks within remote environments. However, most teleoperation systems developed previously have heavily relied on continuous communication or a network with higher sampling rates. In this study, the authors propose novel control schemes to guarantee stability and tracking performance of bilateral teleoperation by considering an event‐based transmission. Based on local output signals and the proposed triggering mechanisms, the master and slave robots transmit signals over a communication network only when the triggering conditions are satisfied. An event‐triggered coordinating controller is presented to guarantee stability and position tracking for non‐linear teleoperators. Input‐to‐state stability of the proposed teleoperation system with bounded external forces is studied with guaranteed static force reflection. Subsequently, a transformation‐based framework is addressed with the event‐triggered coordinating control to cope with bilateral teleoperation systems under time delays. The Zeno behaviour is demonstrated to be excluded in the proposed event‐triggered teleoperation systems. Numerical examples and experiments are presented to discuss the efficacy of the proposed event‐triggered teleoperation systems.
Coordinated control of MMC‐HVDC system with offshore wind farm for providing emulated inertia support
Authors: Zeng Xueyang , Liu Tianqi , Wang Shunliang , Dong Yuqing , Li Baohong , Chen Zhe
Published: November 2019

With the continuous increase of renewable energy generation and high voltage direct current (HVDC) power transmission, the system inertia is declining, thus resulting in greater risks of frequency instability. To solve this issue, a dc‐link inertia control is firstly proposed for a point‐to‐point modular multilevel converter based HVDC (MMC‐HVDC) link, which enables the MMC‐HVDC system to provide emulated inertia support by employing the electrostatic energy stored in the dc capacitors. Moreover, in order to maintain reasonable submodule capacitor size as well as provide more emulated inertia support, a virtual capacitor control for MMC‐HVDC connected an offshore wind farm (OWF) is proposed. With the virtual capacitor control, the OWF is able to provide a large capacity virtual capacitor in dc side of MMC‐HVDC link and supply desired emulated inertia support for onshore power system by utilising the offshore wind turbines’ rotor rotational kinetic energy. Furthermore, a procedure for selecting the appropriate virtual capacitor control parameters is proposed. Finally, the performance of the proposed coordinated control is researched in PSCAD/EMTDC, and the simulation results show that the onshore power system inertia is effectively improved with the coordinated control.
Increasing operational flexibility of integrated energy systems by introducing power to hydrogen
Authors: Ge Pudong , Hu Qinran , Wu Qiuwei , Dou Xiaobo , Wu Zaijun , Ding Yiyuan
Published: November 2019

Owing to the limited operating regions of combined heat and power (CHP) units, the operation of integrated energy systems suffers from low flexibility, low‐cost efficiency, renewable curtailment etc. Meanwhile, as the capacity of renewable energies keeps growing and integrating into power systems, various methods, such as installing electric boilers to enable electricity‐heat conversion, have been developed to absorb excessive renewables and increase system operation flexibility. To further increase the system operation flexibility, this study explores the possibilities of utilising electrolysers and hydrogen storage tanks to enable electricity‐hydrogen‐heat conversion. To better visualise the enhanced flexibility, this study presents extra flexibilities from electric boilers, electrolysers and hydrogen tanks as the equivalent operating region expansion for CHP units. In this study, the system is modelled as a mixed‐integer optimisation problem which balances the electricity, heat and hydrogen demands in a 24‐hour period. A 6‐bus test system is used in the case studies to illustrate the effectiveness of implementing electrolysers and hydrogen storage tanks. The optimisation results show the application of hydrogen energy improves the system operation flexibility, reduces wind curtailment, thereby decreasing fuel consumption and carbon emission.
ANN‐based robust DC fault protection algorithm for MMC high‐voltage direct current grids
Authors: Xiang Wang , Yang Saizhao , Wen Jinyu
Published: November 2019

Fast and reliable protection is a significant technical challenge in the modular multilevel converter (MMC)‐based DC grids. The existing fault detection methods suffer from the difficulty in setting protective thresholds, incomplete function, insensitivity to high‐resistance faults and vulnerable to noise. This study proposes an artificial neural network (ANN)‐based method to enable DC bus protection and DC line protection for DC grids. The transient characteristics of DC voltages are analysed during DC faults. On the basis of the analysis, the discrete wavelet transform is used as an extractor of distinctive features at the input of the ANN. Both frequency‐domain and time‐domain components are selected as input vectors. A large number of offline data considering the impact of noise is employed to train the ANN. The outputs of the ANN are used to trigger the DC line and DC bus protections and select the faulted poles. The proposed method is tested in a four‐terminal MMC‐based DC grid under PSCAD/EMTDC. The simulation results verify the effectiveness of the proposed method in fault identification and the selection of the faulty pole. The intelligent algorithm‐based protection scheme has good performance concerning selectivity, reliability, robustness to noise and fast action.
FPGA‐based reconfigurable matrix inversion implementation for inverse filtering of multi‐channel SAR imaging
Authors: Li HuiXing , Feng YangKai , Hu ShanQing , Li BingYi , Xie YiZhuang , Wu MengChao
Published: November 2019

In multi‐channel synthetic aperture radar (SAR), the azimuth non‐uniform sampling tends to result in a large number of virtual point targets, which are not expected. Inverse filter algorithm provides a new idea for solving this problem. This way can be abstracted as a matrix inversion in essence, which becomes the key factor that affects the real‐time and accuracy of multi‐channel pre‐processing. This study presents the implementation of matrix inversion method on field programmable gate array (FPGA), based on lower and upper triangular matrix (LU) decomposition algorithm. In this process, the efficient parallelism of FPGA and the rich floating‐point intellectual property (IP) cores are fully utilised to speed up the process of inverting the matrix with a data type of 32‐bit single‐precision floating‐point. In this design, the parallelism of the algorithm was fully considered and a hierarchical iterative processing strategy was adopted to realise the reconfigurable storage and computing unit both. At the same time, in order to achieve the balance of resources and efficiency, a reusable structure was proposed also, using the pipeline technology and appropriate data scheduling. Finally, Modelsim platform is used to observe the simulation results, and the performance can be detected combined with MATLAB platform. At last, the computational accuracy is up to , and the speedup ratio can reach about .
Subvastus Exposure Compared to Parapatellar Approach in Navigated Sequential Bilateral Total Knee Arthroplasty (SBTKA): A Prospective Randomized Study
Authors: Jhurani Anoop , Agarwal Piyush , Aswal Mukesh , Rasquinha Chetan , Srivastava Mudit
Published: November 2019

Subvastus approach preserves the quadriceps mechanism and may lead to improved early functional outcomes as compared with a parapatellar approach in primary knee arthroplasty. We performed a prospective randomized study to test the hypothesis if subvastus approach improves patient- and physician-reported outcomes in navigated sequential bilateral knee arthroplasty when compared with the standard parapatellar approach. A total of 93 patients were allotted in each group after power analysis and randomization done by computer-generated sequence: group S by subvastus approach and control group P by parapatellar approach. The patient's ability to walk without an aid, range of motion, blood loss, tourniquet time, complications, Knee Society Score (KSS), Knee Society Functional Score (KSFS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS), High Flexion Knee Score (HFKS), and visual analog scale (VAS) for pain were recorded preoperatively and postoperatively at 2 and 6 weeks and 3, 6, and 12 months. Final follow-up was done at 2 years. There was no statistical difference in the patient's ability to achieve a straight leg raise (p = 0.88), walk without an aid (p = 0.25), leaving pain medication (p = 0.48), and mean duration of hospital stay (p = 0.58) between both groups. There was no difference in KSS, FS, KOOS, WOMAC, HFKS, and VAS at 2 weeks and later follow-ups. There was no significant difference in range of motion or lateral retinacular release in both groups. Blood loss was significantly less in group S (p < 0.05), but there was a higher rate of proximal wound dehiscence and delayed healing in subvastus group (p = 0.03). Subvastus approach does not improve patient- and physician-reported outcome measures except blood loss in computer-navigated sequential bilateral knee arthroplasty and has an increased incidence of wound healing problems. The Level of evidence for the study is I.
Cardiopulmonary Bypass Strategy to Facilitate Transfusion-Free Congenital Heart Surgery in Neonates and Infants
Authors: Boettcher Wolfgang , Dehmel Frank , Redlin Mathias , Sinzobahamvya Nicodème , Photiadis Joachim
Published: November 2019

Priming the cardiopulmonary bypass (CPB) circuit without the addition of homologous blood constitutes the basis of blood-saving strategies in open-heart surgery. For low-weight patients, in particular neonates and infants, this implies avoidance of excessive hemodilution during extracorporeal circulation. The circuit has to be miniaturized and tubing must be cut as short as possible to reduce the priming volume to prevent unacceptable hemodilution with initiating CPB. During perfusion, measures should be taken to prevent blood loss from the primary circuit to avoid replacement by additional volume. Favorable factors such as mild hypothermia/normothermia and high heparin concentrations during extracorporeal circulation promote earlier hemostasis after coming off bypass.

Lower mortality score, first chest entry, higher hemoglobin concentration before going on bypass, and shorter CPB duration support transfusion-free CPB procedure. Reduced postoperative morbidity and mortality were observed when CPB was performed without blood transfusion. In our experience, this can be achieved in at least 70% of CPBs, even in low-weight patients.

Bloodless CPB circuit priming should become a widespread reality, even in neonates and young infants, in any open-heart procedure.
Atrial Resection without Cardiopulmonary Bypass for Lung Cancer
Authors: Galetta Domenico , Spaggiari Lorenzo
Published: November 2019

Background Results of resection of lung cancer invading left atrium (T4atrium) without cardiopulmonary bypass (CPB) remain controversial. We reviewed our experience analyzing surgical results and postoperative outcomes.

Methods Patients who underwent extended lung resection for T4atrium without CPB between 1998 and 2018 were retrospectively reviewed using a prospective database.

Results The study included 44 patients (34 males and 10 females; median age: 63 years). Twenty-five patients underwent preoperative mediastinal staging and 27 received induction treatment (IT). Surgery included 40 (90.9%) pneumonectomies, 3 (6.8%) lobectomies, and 1 bilobectomy (2.3%). Pathological nodal status was N0 in 10 patients (22.7%), N1 in 18 (40.9%), and N2 in 16 (36.4%). Four patients receiving IT had a complete pathological response (9.1%). Eight (18.2%) patients had microscopic tumor evidence on atrial resected margins. Mortality was nil. The major complication rate was 11.4%, including one bronchopleural fistula, one cardiac herniation, and three hemothoraces, all requiring reintervention. The minor complication rate was 25.5%. After a median survival of 37 months (range: 1–144 months), 20 (45.4%) patients were alive. Five-year survival rate and disease-free interval were 39 and 45.8%, respectively. Patients with N0 and R0 disease had a best prognosis (log-rank test: p = 0.03 and p = 0.01, respectively). IT neither influenced survival nor postoperative complications. On multivariate analysis, pN0 (p = 0.04 [95% confidence interval [CI]: 0.65–9.66] and negative atrial margins (p = 0.02 [95% CI: 0.96–8.35]) were positive independent prognostic factors.

Conclusions T4atrium is technically feasible without mortality and acceptable morbidity. Patients with N2 cancers should not be operated. T4atrium should not be systematically considered as a definitive contraindication to surgery.
A hybrid forecasting system based on multi-objective optimization for predicting short-term electricity load
Authors: Song Yanru , Yang Yi , He Zhaoshuang , Li Caihong , Li Lian
Published: November 2019

Short-term load forecasting (STLF) plays a significant role in economic and social development. As a challenging but indispensable task, STLF has become a hot topic in the field of energy. However, the inadequacy of existing methods lies in their inability to capture accurate input features that are highly related to the output, as the main focus of research has been on improving the accuracy of STLF, while ignoring its stability. Therefore, in this paper, a novel, robust hybrid forecasting system was developed, composed of four modules: (1) data preprocessing, (2) forecasting, (3) optimization, and (4) evaluation. In the data preprocessing module, an effective data preprocessing scheme based on singular spectrum analysis and gray correlation analysis was used to produce a smoother time series and to mine the best input and output structure for the model. An extreme learning machine (ELM) optimized using a multiobjective genetic algorithm (MOGA) that considers both the forecasting accuracy and stability was employed to provide the forecasting. Additionally, a generalized regression neural network (GRNN) was also used in the subsequent module to perform forecasting. Moreover, to further obtain accurate results and to overcome the drawbacks of using single models, a simulated annealing (SA) algorithm was utilized to optimize the combined parameters of the MOGA–ELM and GRNN algorithms in the optimization module. To validate the proposed model, half-hourly load data from the New South Wales and Tasmania are provided as illustrative cases. The experimental results show that the proposed hybrid model obtains more accurate and stable results than the reference models used for comparison.
SHH signaling mediated by a prechordal and brain enhancer controls forebrain organization
Authors: Sagai Tomoko , Amano Takanori , Maeno Akiteru , Ajima Rieko , Shiroishi Toshihiko
Published: November 2019

Sonic hedgehog (SHH) signaling plays a pivotal role in 2 different phases during brain development. Early SHH signaling derived from the prechordal plate (PrCP) triggers secondaryShhinduction in the forebrain, which overlies the PrCP, and the induced SHH signaling, in turn, directs late neuronal differentiation of the forebrain. Consequently,Shhregulation in the PrCP is crucial for initiation of forebrain development. However, no enhancer that regulates prechordalShhexpression has yet been found. Here, we identified a prechordal enhancer, named SBE7, in the vicinity of a cluster of known forebrain enhancers forShh. This enhancer also directsShhexpression in the ventral midline of the forebrain, which receives the prechordal SHH signal. Thus, the identified enhancer acts not only for the initiation ofShhregulation in the PrCP but also for subsequentShhinduction in the forebrain. Indeed, removal of the enhancer from the mouse genome markedly down-regulated the expression ofShhin the rostral domains of the axial mesoderm and in the ventral midline of the forebrain and hypothalamus in the mouse embryo, and caused a craniofacial abnormality similar to human holoprosencephaly (HPE). These findings demonstrate that SHH signaling mediated by the newly identified enhancer is essential for development and growth of the ventral midline of the forebrain and hypothalamus. Understanding of theShhregulation governed by this prechordal and brain enhancer provides an insight into the mechanism underlying craniofacial morphogenesis and the etiology of HPE.
Membrane intercalation-enhanced photodynamic inactivation of bacteria by a metallacycle and TAT-decorated virus coat protein
Authors: Gao Sijia , Yan Xuzhou , Xie Guocheng , Zhu Meng , Ju Xiaoyan , Stang Peter J. , Tian Ye , Niu Zhongwei
Published: November 2019

Significance

Photodynamic inactivation (PDI), which has led to little antibiotic resistance, plays a promising role in the control of bacterial infection. Its main mechanism is the damage of membrane components by reactive oxygen species (ROS). However, achieving bacterial membrane intercalation of the photosensitizers remains a challenge. Here, we report the self-assembly of an aggregation-induced emission active photosensitizer with a cell-penetrating peptide-decorated virus coat protein. This assembly exhibits both ROS generation and a strong membrane-intercalating capacity, resulting in significantly enhanced PDI efficiency against bacteria. Especially for
Escherichia coli
possessing outer membrane, this assembly decreases the survival rate to nearly zero upon light irradiation. This study has implications from the control of bacterial infection to the generation of multifunctional nanomaterials.
Nucleation and dissociation of methane clathrate embryo at the gas–water interface
Authors: Liang Rongda , Xu Huijie , Shen Yuneng , Sun Shumei , Xu Jiyu , Meng Sheng , Shen Y. Ron , Tian Chuanshan
Published: November 2019

Significance

Clathrate hydrates are of great current interest because of their relevance to energy and environment. Methane clathrate has attracted particular attention for being the world’s largest natural gas resources beneath permafrost and ocean sediments. Yet nucleation of clathrate is still a poorly understood process although its knowledge is crucial for control of clathrate formation and dissociation in many applications. In this work, we used sum-frequency vibrational spectroscopy to probe water under high-pressure methane vapor, and found that nucleation and growth of methane clathrates start at methane–water interface. The spectral change with lowering temperature showed evidence that similar to usual crystal growth, clathrates begin to form when nuclei of cage-like methane–water complex structure at the water interface reach critical size.
Pericytes enable effective angiogenesis in the presence of proinflammatory signals
Authors: Kang Tae-Yun , Bocci Federico , Jolly Mohit Kumar , Levine Herbert , Onuchic José Nelson , Levchenko Andre
Published: November 2019

Angiogenesis frequently occurs in the context of acute or persistent inflammation. The complex interplay of proinflammatory and proangiogenic cues is only partially understood. Using an experimental model, permitting exposure of developing blood vessel sprouts to multiple combinations of diverse biochemical stimuli and juxtacrine cell interactions, we present evidence that a proinflammatory cytokine, tumor necrosis factor (TNF), can have both proangiogenic and antiangiogenic effects, depending on the dose and the presence of pericytes. In particular, we find that pericytes can rescue and enhance angiogenesis in the presence of otherwise-inhibitory high TNF doses. This sharp switch from proangiogenic to antiangiogenic effect of TNF observed with an escalating dose of this cytokine, as well as the effect of pericytes, are explained by a mathematical model trained on the biochemical data. Furthermore, this model was predictive of the effects of diverse combinations of proinflammatory and antiinflammatory cues, and variable pericyte coverage. The mechanism supports the effect of TNF and pericytes as modulating signaling networks impinging on Notch signaling and specification of the Tip and Stalk phenotypes. This integrative analysis elucidates the plasticity of the angiogenic morphogenesis in the presence of diverse and potentially conflicting cues, with immediate implications for many physiological and pathological settings.
Markovian approaches to modeling intracellular reaction processes with molecular memory
Authors: Zhang Jiajun , Zhou Tianshou
Published: November 2019

Significance

Modeling intracellular processes has long relied on the markovian assumption. However, as soon as a reactant interacts with its environment, molecular memory definitely exists and its effects cannot be neglected. Since the Markov theory cannot translate directly to modeling and analysis of nonmarkovian processes, this leads to many significant challenges. We develop a formulation, namely the stationary generalized chemical-master equation, to model intracellular processes with molecular memory. This formulation converts a nonmarkovian question to a markovian one while keeping the stationary probabilistic behavior unchanged. Both a stationary generalized Fokker–Planck equation and a generalized linear noise approximation are further developed for the fast evaluation of fluctuations. These formulations can have broad applications and may help us discover new biological knowledge.
N
,
N
′-Diacetyl-
p
-phenylenediamine restores microglial phagocytosis and improves cognitive defects in Alzheimer’s disease transgenic mice
Authors: Park Min Hee , Lee Misun , Nam Geewoo , Kim Mingeun , Kang Juhye , Choi Byung Jo , Jeong Min Seock , Park Kang Ho , Han Wan Hui , Tak Eunyoung , Kim Min Sun , Lee Juri , Lin Yuxi , Lee Young-Ho , Song Im-Sook , Choi Min-Koo , Lee Joo-Yong , Jin Hee Kyung , Bae Jae-sung , Lim Mi Hee
Published: November 2019

As a central feature of neuroinflammation, microglial dysfunction has been increasingly considered a causative factor of neurodegeneration implicating an intertwined pathology with amyloidogenic proteins. Herein, we report the smallest synthetic molecule (
N
,
N
′-diacetyl-
p
-phenylenediamine [DAPPD]), simply composed of a benzene ring with 2 acetamide groups at the
para
position, known to date as a chemical reagent that is able to promote the phagocytic aptitude of microglia and subsequently ameliorate cognitive defects. Based on our mechanistic investigations in vitro and in vivo, 1) the capability of DAPPD to restore microglial phagocytosis is responsible for diminishing the accumulation of amyloid-β (Aβ) species and significantly improving cognitive function in the brains of 2 types of Alzheimer’s disease (AD) transgenic mice, and 2) the rectification of microglial function by DAPPD is a result of its ability to suppress the expression of NLRP3 inflammasome-associated proteins through its impact on the NF-κB pathway. Overall, our in vitro and in vivo investigations on efficacies and molecular-level mechanisms demonstrate the ability of DAPPD to regulate microglial function, suppress neuroinflammation, foster cerebral Aβ clearance, and attenuate cognitive deficits in AD transgenic mouse models. Discovery of such antineuroinflammatory compounds signifies the potential in discovering effective therapeutic molecules against AD-associated neurodegeneration.
The role of land cover change in Arctic-Boreal greening and browning trends
Authors: Wang Jonathan A , Friedl Mark A
Published: November 2019

Many studies have used time series of satellite-derived vegetation indices to identify so-called greening and browning trends across the northern high-latitudes and to suggest that the productivity of Arctic-Boreal ecosystems is changing in response to climate forcing at local and continental scales. However, disturbances that alter land cover are prevalent in Arctic-Boreal ecosystems, and changes in Arctic-Boreal land cover, which complicate interpretation of trends in vegetation indices, have mostly been ignored in previous studies. Here we use a new land cover change dataset derived from Landsat imagery to explore the extent to which land cover and land cover change influence trends in the normalized difference vegetation index (NDVI) over a large (3.76 M km2) area of NASA’s Arctic Boreal Vulnerability Experiment, which spans much of northwestern Canada and Alaska. Between 1984 and 2012, 21.2% of the study domain experienced land cover change and 42.7% had significant NDVI trends. Land cover change occurred in 27.6% of locations with significant NDVI trends during this period and resulted in greening and browning rates 48%–128% higher than in areas of stable land cover. While the majority of land cover change areas experienced significant NDVI trends, more than half of areas with stable land cover did not. Further, the extent and magnitude of browning and greening trends varied substantially as a function of land cover class and land cover change type. Forest disturbance from fire and timber harvest drove over one third of statistically significant NDVI trends and created complex mosaics of recent forest loss (as browning) and post-disturbance recovery (as greening) at both landscape and continental scale. Our results demonstrate the importance of land cover changes in highly disturbed high-latitude ecosystems for interpreting trends of NDVI and productivity across multiple spatial scales.
Exploring the stationarity of Australian temperature, precipitation and pan evaporation records over the last century
Authors: Ukkola A M , Roderick M L , Barker A , Pitman A J
Published: November 2019

Australia has experienced regional climate trends over recent decades with consequences for agriculture and water management. We investigate the statistical significance of these trends at annual and seasonal scales using the concept of stationarity. Using long-term high quality regional-scale observations of temperature, precipitation and pan evaporation (a measure of atmospheric evaporative demand), we find that despite highly significant increases in temperature that are non-stationary, few regions of Australia have experienced annual or seasonal changes in precipitation or pan evaporation that are outside the range of observed variability over the last century. Despite a common assumption of increasing water demand under a warming climate, atmospheric evaporative demand (as measured by pan evaporation) largely remains unchanged. This is because evaporative demand depends strongly on factors other than temperature. Similarly, seasonal and annual precipitation over the last century is found to be stationary in most (but not all) regions. These findings suggest that the Australian precipitation has largely remained within the bounds of observed variability to date and emphasises the need to better account for variability in water resource management.
Voter model on networks partitioned into two cliques of arbitrary sizes
Authors: Gastner Michael T , Ishida Kota
Published: November 2019

The voter model is an archetypal stochastic process that represents opinion dynamics. In each update, one agent is chosen uniformly at random. The selected agent then copies the current opinion of a randomly selected neighbour. We investigate the voter model on a network with an exogenous community structure: two cliques (i.e. complete subgraphs) randomly linked by X interclique edges. We show that, counterintuitively, the mean consensus time is typically not a monotonically decreasing function of X. Cliques of fixed proportions with opposite initial opinions reach a consensus, on average, most quickly if X scales as N
3/2, where N is the number of agents in the network. Hence, to accelerate a consensus between cliques, agents should connect to more members in the other clique as N increases but not to the extent that cliques lose their identity as distinct communities. We support our numerical results with an equation-based analysis. By interpolating between two asymptotic heterogeneous mean-field approximations, we obtain an equation for the mean consensus time that is in excellent agreement with simulations for all values of X.
Analysis and Research on Wind Energy Utilization in Wind Field of Urban Buildings
Authors: Su Qiaoling
Published: November 2019

With the concentration of urban population and the development of construction technology, more and more high-rise buildings with irregular shapes and different heights have been built. These buildings have a greater impact on the surrounding wind field.[1] And the turbulent strong wind field between urban high-rise buildings also brings many inconveniences to the life of the surrounding residents. The purpose of this study is to discuss the utilization value of wind energy in turbulent strong wind field by analyzing the wind field between simulated urban high-rise buildings and to explore the possibility of installing wind energy collectors in appropriate locations and to turn waste into treasure. This study also discusses the possibility of wind energy utilization and value. At the same time, through the grid division of the wind field area, the wind field situation is simulated and other factors are considered comprehensively, it is possible to find a proper position of wind energy utilization. The results show that the wind speed distribution of high-rise buildings has a higher wind speed in the corridor between buildings. And for a single building, the wind speed at the middle is higher than that on the ground and the top. This provides the possibility of collecting and utilizing wind energy among buildings.
Practice and Effect of Fine Development in High Water Cut Stage of An Oilfield
Authors: Ji Guangpeng
Published: November 2019

In order to improve the development effect of An oil field Oilfield in high water cut stage, the author has adopted the method of fine reservoir characteristics description, fine injection-production system adjustment, fine injection-production structure adjustment and further studied on the reservoir development characteristics and channel sand body sedimentary model, remaining oil type and potential, single sand body tapping potential. The results show that, based on the correct understanding of the characteristics of reservoir sedimentation, using the favorable timing of encryption and carrying out the adjustment of injection and production system to determine methods of improving relationship of injection-production in different types of sand bodies and improve the control degree of water flooding. By studying on injection-production adjustment of different area, Well patterns and sand bodies, the matching adjustment of the two well patterns is realized, and three kinds of planimetric connectivity and longitudinal “345” subdivision boundaries are determined. Using the technology of “five directions” tapping potential and fine development, the oil field decline has been effectively controlled and the development effect has been improved.
A Speech Denoising Algorithm Based on Harmonic Regeneration
Authors: Zengyuan Liu , Anming Dong
Published: November 2019

Single channel speech enhancement in noisy environments is studied in this paper. Traditional speech enhancement methods that based on short time spectral analysis frequently introduce harmonic distortion due to imprecise noise spectral estimation. A kind of technology which is called harmonic regeneration is used to overcome the defect of traditional speech enhancement methods, and damaged harmonics are restored. Firstly, a non-linear operation is used on the harmonic distorted signal to generate an artificial signal which contains all of harmonics of pure speech signal. Secondly, the artificial signal is used to correct the traditional noise reduction gain function, and the purpose of harmonic reservation is reached. Theoretical analysis, objective and subjective results indicate that the harmonic regeneration algorithm can improve speech quality dramatically. The computational complexity of the new algorithm is rather low, and it can be easily implemented in real time applications.
Optimization of revised universal soil loss equation of ecological forest lands in the hilly areas of the eastern Zhejiang Province
Authors: Wang Ran , Chen Jijiang , Li Gang , Zou Yefeng , Lu Fangchun , Zhou Xijiong
Published: November 2019

The soil erosion prediction model is an effective means to predict soil erosion and soil and water conservation planning. Based on the analysis of soil erosion law of typical economic forest slopes in the study area, it is of great significance to establish a prediction model for soil loss in typical economic forests in the study area. In this study, five typical economic forest slope runoff plots in the study area were used as research objects. The runoff and sediment data under natural rainfall conditions were used to optimize the universal soil loss equation. The prediction equation for soil and water loss in the hilly areas of the eastern Zhejiang Province was proposed: A= 0.004·R1.594·K·LS·C·P. The Nash efficiency coefficients of the simulation results are above 0.70, and the coefficients of determination are above 0.80.
Streptomycin Pharmaceutical Wastewater affects the T-AOC and CAT activity of Zebrafish
Authors: Wu Pengpeng , Wang Yaxue , Shen Hong-Yan
Published: November 2019

Streptomycin is increasingly being used to treat human diseases. Recently, its toxic effects on aquatic organisms have attracted global attention. The aim of this study was to investigate the toxic effects of streptomycin on zebrafish by measuring T-AOC and CAT activity. Zebrafish were exposed to four different volume concentrations of streptomycin wastewater and their T-AOC and CAT activities were measured at 3, 6, 9, 12 and 15 days. T-AOC activity shows an inverted “N” trend, and T-AOC activity reached the maximum (1.90U·mgprot−1) on the 12th days. Furthermore, The CAT activity shows “M” tendency, and concentrations of streptomycin can affect CAT activity. Streptomycin wastewater induced oxidative stress in Zebrafish muscle tissue.
Sloshing effect of back pressure fluctuation of oil filling pipe in oil tank inheavy sea
Authors: Yuan SJ , Zhu K B , Yang Y , Zhen Y Y , Zhu ZQ
Published: November 2019

During the loading operation of the oil tanker, the oil sloshing is caused by the movement of the carrier liquid and the filling of the liquid cargo. The sloshing force acts on the filling pipe and affects the filling process of the tanker. The main aim of this paper is to back pressure fluctuation of oil filling pipe in oil tank. A more reasonable three-dimensional model was established, and the VOF (volume-of-fluid) model was combined to simulated the change of back pressure. This paper firstly compares the sloshing loads caused by tank loading and movement. The results show that the effect of tank loading on the back pressure of the filling pipe is less than the impact of the tank movement. On this basis, the article further studies the sloshing effect of the tank movement. The test simulated different amplitude of tank to compare and analyze the back pressure variation characteristics of the filling. The results of simulation show that during the tank loading operation, the sloshing pressure load becomes larger as the motion period decreases.
Preliminary Geomagnetic Study of the Hot Spring Area in Rokan Hulu, Riau - Indonesia
Authors: Islami Nur , Irianti Mitri
Published: November 2019

Hot spring is commonly found in volcanic mountain areas. But in Rokan Hulu, a hot spring is found at a distance of about 15 km from the hills of Bukit Barisan. This study aims to conduct a physical study especially preliminary geomagnetic study of the Hot Spring in terms of the magnetic properties and topography of the area. As much as 26 points of the geomagnetic survey were conducted and used in this study. Some data corrections were applied to the data for making the reliable data interpretation. The results showed that there was a weakening of the magnetic field in the zone around Hot Spring itself and the low magnetic value was extended to the Southeast zone of Hot Spring. Topography shows the zone in this southeast has a height difference of fewer than 10 meters from the location of the Hot Spring. Allegedly this weak Magnetic zone is the source of heat from the Hot Spring.
Design of corneal cross-linking system: with real-time positioning of pupil position
Authors: Zheng Tianli , Yao Kang , Zhu Hailong , Fu Weiwei
Published: November 2019

This paper presents a design of a corneal cross-linking instrument with the function of tracking and locating the central position of the pupil in real time. According to the application requirements, based on the principle of uniform light of compound eye lens, the optical projection system of the corneal crosslinking instrument with the diameter of the treatment spot being 9mm and the uniformity being greater than 90% was designed. And put forward a kind of the pupil localization algorithm, the acquisition of the pupil image gray processing and calculate the histogram, according to the characters of histogram adaptively to take out the appropriate threshold binarization, again after the binarization of image contour tracking, get accurate boundary, the outline of the final vote based on the sliding arc length increment method to determine the pupil center and radius. Experimental results show that the corneal cross-linking system designed in this paper can not only accurately project the treatment of light spot, but also accurately track the central position of the pupil of the human eye.
Rapid Determination of Resveratrol and Piceid in Wine by High-Performance Liquid Chromatography
Authors: Wei Changbin , Qiao Jian , Ma Zhiling
Published: November 2019

In this study, a solid-phase extraction column dedicated to the detection of resveratrol was directly used for purification after adjusting the pH of the sample, without resorting to a new method for sample extraction. The compounds cis-resveratrol, trans-resveratrol, cis-piceid, and trans-piceid were thus detected in wine simultaneously by high-performance liquid chromatography (HPLC). This method offers rapid and easy operation and involves low consumption of organic solvents, paving the way for efficient determination of the variety and other parameters of grapes used in wine samples..
Research progress of 3D printing materials in stomatology
Authors: Wang Fang
Published: November 2019

3D printing technology is gradually used in the field of stomatology, such as repair, planting, orthodontics and other disciplines. 3D printing process mainly includes four aspects: oral scanning, Digital design, 3D printing materials and 3D printing technology and equipment. The properties of 3D printing materials are the key factors affecting the effect of 3D printing. This paper reviews the research and development of 3D printing materials in stomatology at home and abroad in recent years and prospects the future development of 3D printing materials in that field.
HPLC fingerprinting and pattern recognition of Brazilian green propolis and Chinese propolis
Authors: Zhang Chumei , Liu Meijuan , Liang Zeyu , Yin Guanglign , Li Kunping
Published: November 2019

In order to improve the quality control method for propolis, HPLC fingerprinting and pattern recognition of 12 batches of Brazilian green propolis and 12 batches of Chinese propolis were carried out. HPLC fingerprinting was performed on a C18 column (250 mm × 4.6 mm, 5μm) using gradient elution with methanol-water (containing 0.2% formic acid) as the mobile phase. Similarity analysis was executed on similarity evaluation system for chromatographic fingerprint of TCM (2012A). Pattern recognition was performed by SIMCA-P 13.0 software. As a result, as for the two groups of propolis samples, 21 common peaks were calibrated and 11 of them were identified as chlorogenic acid, caffeic acid, isochlorogenic acid B, isochlorogenic acid C, quercetin, kaempferol, apigenin, pinocembrin, caffeic acid phenylethyl ester, galangin and artepillin C. The similarity of the fingerprint profiles of the tested Brazilian propolis is more than 0.92, and that of the tested Chinese propolis is more than 0.91. However, the two groups of fingerprints’ similarity are from 0.523 to 0.693. The results of PCA and OPLS-DA showed that chemical profiles of the tested Brazilian green propolis were different from those of Chinese propolis. A set of compounds, namely, artepillin C, chlorogenic acid, pinocembrin, isochlorogenic acid B and caffeic acid phenylethyl ester can act as difference marker of the two groups of propolis. Moreover, HPLC fingerprint combined with pattern recognition could be developed into one new method for quality control of propolis.
Research progress of the correlation between porcine Insulin-like growth factor 1 (IGF-I) and growth
Authors: Li Jiajun , Zhang Feiyan , Pan Kangcheng , Ni Xueqin , Yang Miao
Published: November 2019

Insulin-like growth factor 1 (IGF-I) is an important factor which plays the roles in regulating animal growth, development and metabolism. IGF-I also called somatomedin C (SM - C) mainly mediate growth hormone that plays the roles of promoting growth and is a kind of polypeptide regulating cell proliferation and differentiation. The paper review influences of IGFBPS, SNPs of porcine IGF-I gene, IGF-I signaling pathway and feed level on IGF-I, moreover, the correlation between porcine insulin-like growth factor IGF-I and growth..
Hang-off Analysis on Deepwater DST String Evacuation in Typhoon Condition
Authors: Liu Kang , Chen Guoming , Zhu Gaogeng , Dai Ziliang
Published: November 2019

A Drill-stem tested (DST) string system requires relatively longer time for full retrieval, and evacuation during typhoon is an important event in deepwater testing. The hang-off DST string system has a high risk as it experiences strong load due to ocean currents and multi-DOF motion of the floating platform. In this paper, a multi-tube model of DST string system that considers multi-point constraints is presented. Hang-off dynamic analysis, platform heading analysis, and evacuation window analysis are conducted. The results show the stress of the DST string system increase dramatically at top. The translational response of the floating platform has a great influence on the safety of the DST string system. The evacuation window is large in the downstream direction and is infeasible in the upstream direction. The operational performance of the DST string system during hang-off evacuation can be improved when driven in a smaller angle with current and orient the platform heading to reduce heave motion.
Effect of Sorting by a Hydrocyclone on Denitrification Performance of Activated Sludge
Authors: Xu Jiaping , Wang Hualin
Published: November 2019

Denitrification performance is an important indicator of the denitrification process in wastewater treatment. A lateral experiment was carried out on the campus wastewater treatment plants (WWTPs) in East China University of Science and Technology (ECUST) by using a SBR process equipped with a hydrocyclone. The results showed that the hydrocyclone in the SBR process was able to break activated sludge (AS) flocs into smaller flocs because of the rotation and revolution. At the same time, organic carbon sources such as polysaccharides and proteins were released, which supplemented the carbon source of the biochemical pool and improved the denitrification performance. After hydrocyclone treatment, the denitrification performance of sludge flocs increased by more than 50%, and the denitrification rate increased by 20.39%. Under continuous operating conditions, the average denitrification performance increased by 6.43%.
Experimental study on treatment of copper Ions in water by circulating electric-flocculation
Authors: Zhang Zhijie , Wang Quan , Xu Linlin , Chen Yong
Published: November 2019

This study is to change the treatment method of electric-flocculation technology, and the water to be treated enters the electrolysis tank in the form of circulation. Comparison of efficiency and energy consumption by circulating electric-flocculation and ordinary electric-flocculation. Explore the feasibility and energy consumption of the cyclic electric-flocculation method. It is found that the common electric-flocculation method and the cyclic electric-flocculation method have the same removal effect when the copper ion concentration is high, and the effect of voltage on the removal effect is very small; when the copper ion concentration is low, the ordinary electric-flocculation method has better removal effect than the cyclic type. The effect of the removal is good, the voltage has little effect on the removal effect of the common electric-flocculation method, and the effect on the circulation type is greatly affected; as the voltage rises, the limit of the copper ion concentration which is different between the removal effect of the ordinary electric-flocculation method and the circulation type is lowered; Under the same conditions, the energy consumption of ordinary electric-flocculation is always higher than that of the circulating type.
Research on “Three Sealing and One Grouting” Sealing Technology
Authors: Houquan Zhou , Qianqian Ma
Published: November 2019

Taking the 3314 transportation roadway of Wangpo Coal Mine as the research background, the stress and strain characteristics of the roadway after support were studied by FLAC3D numerical simulation. It is determined that the reasonable sealing depth is not less than 15m, and then the “three sealing and one grouting” sealing technique is proposed on the basis of the “two sealing and one grouting” methods, and the two sealing methods are compared and analyzed. The results show that the total average gas concentration and the maximum average gas concentration of the “three sealing and one grouting” sealing technique are 9.5% and 16.5% higher than the “two sealing and one grouting” respectively, and the gas concentration of the borehole after 70 days of drainage is still up to 40%. The “three sealing and one grouting” sealing technique can effectively improve the efficiency of gas drainage.
Synthesis and characterization of a magnetite (Fe3O4) nanofiltration membrane
Authors: Yang Zi , Rui Xiaobo
Published: November 2019

Meso-porous magnetite membranes have been synthesized by dip-coating iron oxide dispersion on ∼2 mm thick α-Al2O3 supports, followed by nitrogen-environment thermal processing. Both gas and water permeabilities of magnetite membranes were investigated. At room temperature, the nitrogen permeance was 3×10−8, which increased to 3×10−7 at 400°C, but decreased to 9×10−8 at 500°C (still higher than room temperature). The argon permeance at corresponding temperature was slightly lower than nitrogen permeance. 0.001mol/L NaCl was used as feed solution for dead-end filtration test. Experimental result indicated the mechanical permeance of magnetite membrane was 5.5×10−16 m, and the maximum salt rejection was 44% at transmembrane pressure of 0.35 MPa. From the perspective of thermal stability, a magnetite membrane was immersed in 60°C deionized (DI) water for a week, and there was no change in thickness according to ellipsometry analysis. Meanwhile, it was found that the membrane was chemically stable in base solution, which is expected for Fe3O4. However, the membrane thickness increased in nitric acid solution at pH 5.0, which was tentatively ascribed to oxidation of Fe3O4 to Fe2O3.