bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of a Carrier Free Dry Powder Inhalation Formulation of Ketotifen for Pulmonary Drug Delivery
Authors: Azari Fariba , Ghanbarzadeh Saeed , Safdari Rezvan , Yaqoubi Shadi , Adibkia Khosro , Hamishehkar Hamed
Published: September 2019

Background Pulmonary drug delivery route is gaining much attention because it enables to target the active ingredients directly to lung both for local and systemic treatments, which maximize the therapeutic effect and minimize unwanted systemic toxicity. Dry powder inhaler (DPI) systems for asthma therapy have shown several merits to the other pulmonary delivery systems such as nebulizers and metered dose inhalers.

Purpose The present study aims to develop and optimize a DPI formulation for Ketotifen fumarate through spray drying technique.

Methods Particles size and morphology, crystallinity, and drug-excipient interaction of fabricated DPI formulations were evaluated by scanning electron microscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and Fourier Transform Infrared Spectroscopy methods, respectively. The aerosolization indexes and aerodynamic properties of dry powders were determined by next generation impactor. The powder flowability was assessed by measuring the Hausner ratio and compressibility index.

Results Among solvent systems, ethanol-water mixture produced the most desirable powder property for inhalation after spray drying. Although co-spray dried formulations with ammonium bicarbonate resulted in the porous structure, it was not beneficial for DPI formulations due to the interaction with Ketotifen. DSC and XRD experiments proved the amorphous structure of prepared powders, which were stable for 12 months.

Conclusion The results of this study demonstrate the potential of Ketotifen DPI formulation and pave a way to use it easily in an industrial scale.
Spatio-Temporal Distribution of Tuberculosis in an Urban Setting in Germany
Authors: Pusch L.-M. , Funke N. , Wiesmüller G. , Kistemann T. , Neuhann F.
Published: September 2019

Background Big cities in Europe have the highest incidence rates of TB in otherwise low incidence settings. Understanding of the spatio-temporal patterns of TB incidence can support efforts for TB prevention and control in line with the End-TB Strategy of the WHO in such settings for low incidence settings.

Methods Data from the municipal TB register of Cologne collected between 2006 and 2015 under the infection prevention legislation were retrieved, addresses geographically identified and all notified incident TB cases retrospectively analysed for their spatial and temporal distribution in this large German city using a geographic information system.

Results During the analysed period 1,038 incident cases were reported, equivalent to an incidence rate of 10.03 cases per 100,000 inhabitants. Contagious pulmonary TB contributed 57 % of all cases. Distribution patterns changed over time with decreases in 37 and increases in 22 of the 77 urban sub-districts, three of which showing constant high rates of TB incidence.

Conclusion The study presents a complementary method to monitor the distribution and development of incident TB cases at a disaggregated level of urban sub-districts. Identification of areas with comparatively high incidence can support identification of clusters respectively their prevention and allow better planning for targeted local TB services.
Closed Reduction as Therapeutic Gold Standard for Treatment of Congenital Hip Dislocation
Authors: Walter Sebastian G. , Bornemann Rahel , Koob Sebastian , Ossendorff Robert , Placzek Richard
Published: September 2019

Background Congenital hip dislocation (luxation) has an incidence of 0.4 – 0.7% and is regarded as a prearthrotic deformity. Thus, if not being diagnosed and treated at a very early age, extensive surgical measures are inevitable in childhood and early adulthood.

Methods In the time between 01/2013 and 02/2019 we performed 28 600 hips sonographies in babies as part of general screening measures at U2 or U3. There were 71 instable, dysplastic or dislocated hips diagnosed that were treated by arthrographic, closed reduction. After a hip spica cast was applied, reposition was controlled by MRI, estimating the acetabular head index (ACI), the head coverage index (HCI) as well as the femoral headʼs sphericity or by sonography using the Graf method.

Results Overall success rate was 91.6% for primary closed reduction. Patients with primarily irreducible hips were significantly older (p < 0.003) than patients with primarily successful reducible hips. Congenital dislocated hips had significantly higher ACIs (p < 0.001) and HCIs (p = 0.03) as well as significantly less well rounded femoral heads (sphericity; p < 0.001) compared to stable hips.

Conclusion Early diagnosis and treatment of congenital dislocated hips by closed reduction is essential for a sufficient and regular maturation of the hips without further surgical interventions.
Visualization of Cardiac Implantable Electronic Device Data for Older Adults Using Participatory Design
Authors: Ahmed Ryan , Toscos Tammy , Rohani Ghahari Romisa , Holden Richard J. , Martin Elizabeth , Wagner Shauna , Daley Carly , Coupe Amanda , Mirro Michael
Published: September 2019

Patients with heart failure (HF) are commonly implanted with cardiac resynchronization therapy (CRT) devices as part of their treatment. Presently, they cannot directly access the remote monitoring (RM) data generated from these devices, representing a missed opportunity for increased knowledge and engagement in care. However, electronic health data sharing can create information overload issues for both clinicians and patients, and some older patients may not be comfortable using the technology (i.e., computers and smartphones) necessary to access this data. To mitigate these problems, patients can be directly involved in the creation of data visualization tailored to their preferences and needs, allowing them to successfully interpret and act upon their health data. We held a participatory design (PD) session with seven adult patients with HF and CRT device implants, who were presently undergoing RM, along with two informal caregivers. Working in three teams, participants used drawing supplies and design cards to design a prototype for a patient-facing dashboard with which they could engage with their device data. Information that patients rated as a high priority for the “Main Dashboard” screen included average percent pacing with alerts for abnormal pacing, other device information such as battery life and recorded events, and information about who to contact with for data-related questions. Preferences for inclusion in an “Additional Information” display included a daily pacing chart, health tips, aborted shocks, a symptom list, and a journal. These results informed the creation of an actual dashboard prototype which was later evaluated by both patients and clinicians. Additionally, important insights were gleaned regarding the involvement of older patients in PD for health technology.
Design and Evaluation of an Integrated, Patient-Focused Electronic Health Record Display for Emergency Medicine
Authors: Wang Xiaomei , Kim Tracy C. , Hegde Sudeep , Hoffman Daniel J. , Benda Natalie C. , Franklin Ella S. , Lavergne David , Perry Shawna J. , Fairbanks Rollin J. , Hettinger A. Zachary , Roth Emilie M. , Bisantz Ann M.
Published: September 2019

Background Hospital emergency departments (EDs) are dynamic environments, involving coordination and shared decision making by staff who care for multiple patients simultaneously. While computerized information systems have been widely adopted in such clinical environments, serious issues have been raised related to their usability and effectiveness. In particular, there is a need to support clinicians to communicate and maintain awareness of a patient's health status, and progress through the ED plan of care.

Objective This study used work-centered usability methods to evaluate an integrated patient-focused status display designed to support ED clinicians' communication and situation awareness regarding a patient's health status and progress through their ED plan of care. The display design was informed by previous studies we conducted examining the information and cognitive support requirements of ED providers and nurses.

Methods ED nurse and provider participants were presented various scenarios requiring patient-prioritization and care-planning tasks to be performed using the prototype display. Participants rated the display in terms of its cognitive support, usability, and usefulness. Participants' performance on the various tasks, and their feedback on the display design and utility, was analyzed.

Results Participants provided ratings for usability and usefulness for the display sections using a work-centered usability questionnaire—mean scores for nurses and providers were 7.56 and 6.6 (1 being lowest and 9 being highest), respectively. General usability scores, based on the System Usability Scale tool, were rated as acceptable or marginally acceptable. Similarly, participants also rated the display highly in terms of support for specific cognitive objectives.

Conclusion A novel patient-focused status display for emergency medicine was evaluated via a simulation-based study in terms of work-centered usability and usefulness. Participants' subjective ratings of usability, usefulness, and support for cognitive objectives were encouraging. These findings, including participants' qualitative feedback, provided insights for improving the design of the display.
High Medium-Term Survivorship of Cruciate-Retaining Total Knee Arthroplasties (110 Knees) for Valgus Deformity
Authors: Matar Hosam E. , Thangaraj R. , Saraogi Akash , Raut Videshnandan
Published: September 2019

The main purpose of this article is to evaluate the clinical outcomes and survivorship of cruciate-retaining (CR) knee arthroplasties for valgus deformity. This article is retrospective consecutive series of 110 valgus knees using CR implants with a minimum 2-year follow-up. Deformity correction was achieved using stepwise sequential soft tissue releases (iliotibial band, popliteus tendon, lateral collateral release through sliver femoral condylar osteotomy). Demographic data, range of movement, and degrees of deformity were collected. The Oxford Knee Score (OKS) was used as patients' reported outcome measure at final follow-up. One-hundred and four patients (110 knees) were included (87 females/17 males) with mean age of 68.7 years. Primary diagnosis was osteoarthritis in 85 patients and rheumatoid arthritis in 19 patients. Mean follow-up was 5.5 years (median: 5 years; range: 2–14 years). Preoperative valgus deformity was measured radiographically using the mechanical tibiofemoral angle with a mean 18.6° (standard deviation [SD]: 7.5; range: 11–38°). At final follow-up, mechanical tibiofemoral angle was 3.8° (SD: 1.97; range: 2–8°). A p-value was <0.0001 and mean OKS was 42 (SD: 5.4; range: 36–48) suggesting satisfactory patients' reported outcomes with no implant revision for any cause. CR implants for valgus knees using staged soft tissue releases including sliver condylar osteotomy had excellent medium-term survivorship and satisfactory patient reported outcome measures. The Level of Evidence for this study is IV.
Spatial structure of low-frequency fluctuations throughout the transition of poloidal flow velocity in edge plasmas of LHD
Authors: Moon C. , Kobayashi T. , Ida K. , Tokuzawa T. , Hidalgo C. , Yoshinuma M. , Ogawa K. , Itoh K. , Fujisawa A. ,   LHD Experiment Group
Published: September 2019

It is observed that a low-frequency (∼2 kHz) density fluctuation is excited in a transition of the poloidal flow velocity (Vθ) in the edge magnetic stochastic region of the Large Helical Device plasmas. Furthermore, it is found that the propagation velocity becomes approximately zero in the proximity of the appearance region of the low-frequency fluctuation by using the edge multichannel microwave Doppler reflectometer system. In particular, the low-frequency fluctuation is considered to be transmitted in both directions (inward and outward) away from the excitation position of the fluctuation, which behaves as the precursor of a magnetic fluctuation burst. Afterward, the edge Hα signal intensity is sharply increased.
Calculation of plasma dynamic parameters of the magneto-inertial fusion target with combined exposure
Authors: Kuzenov Victor V. , Ryzhkov Sergei V.
Published: September 2019

The work is devoted to theoretical calculations of compression and energy release processes in the target, which is used in a magnetoinertial fusion (MIF) concept consisting of pulsed jets and intense laser radiation. A numerical technique, describing plasma-physical processes occurring in MIF system, is developed. The results of the calculation of the combined effects (pulsed jets and laser radiation acting on a cylindrical target in the end and perpendicular directions) of intense energy flows on a single-layer cylindrical target are presented. All the main plasma dynamic and radiative parameters of the compressed target plasma were found.
X-ray linear and non-linear spectroscopy of the ESCA molecule
Authors: Nenov Artur , Segatta Francesco , Bruner Adam , Mukamel Shaul , Garavelli Marco
Published: September 2019

Linear and nonlinear X-ray spectroscopy hold the promise to provide a complementary tool to the available ample body of terahertz to UV spectroscopic techniques, disclosing information about the electronic structure and the dynamics of a large variety of systems, spanning from transition metals to organic molecules. While experimental free electron laser facilities continue to develop, theory may take the lead in modeling and inspiring new cutting edge experiments, paving the way to their future use. As an example, the not-yet-available two-dimensional coherent X-ray spectroscopy (2DCXS), conceptually similar to 2D-NMR, is expected to provide a wealth of information about molecular structure and dynamics with an unprecedented level of detail. In the present contribution, we focus on the simulation of linear and non-linear (2DCXS) spectra of the ESCA molecule. The molecule has four inequivalent carbon K-edges and has been widely used as a benchmark for photoelectron spectroscopy. Two theoretical approaches for the computation of the system manifold of states, namely, TDDFT and RASSCF/RASPT2, are compared, and the possible signals that may appear in a 2DCXS experiment and their origin are surveyed.
Routes to singlet exciton fission in rubrene crystals and amorphous films
Authors: Finton Drew M. , Wolf Eric A. , Zoutenbier Vincent S. , Ward Kebra A. , Biaggio Ivan
Published: September 2019

By using wavelength-tunable, low fluence picosecond pulses at a 1 kHz repetition rate in a transient grating pump and probe configuration, we show that photoexcitation to higher vibrational levels leads to slower singlet exciton fission rates in rubrene. After the 1 ps photoexcitation, the initial growth of the triplet exciton population is exponential, with its time-constant systematically varying from 2.5 ± 0.7 ps to 40 ± 15 ps as the excitation photon energy is increased from the lowest to the third main vibrational band in the vibrational progression of rubrene’s absorption spectrum. We also determine that short-pulse-induced fluorescence in amorphous rubrene films deposited by molecular beam epitaxy in high vacuum decays as a single exponential with a lifetime of 15.2 ns, close to rubrene’s radiative lifetime for molecules in solution. This shows that singlet fission is non-existent in fully amorphous rubrene films, despite the close molecular packing, which indicates that in these films there is no short range molecular order matching the molecular arrangement in orthorhombic rubrene crystals.
Modification of O and CO binding on Pt nanoparticles due to electronic and structural effects of titania supports
Authors: Ellaby Tom , Briquet Ludovic , Sarwar Misbah , Thompsett David , Skylaris Chris-Kriton
Published: September 2019

Metal oxide supports often play an active part in heterogeneous catalysis by moderating both the structure and the electronic properties of the metallic catalyst particle. In order to provide some fundamental understanding on these effects, we present here a density functional theory (DFT) investigation of the binding of O and CO on Pt nanoparticles supported on titania (anatase) surfaces. These systems are complex, and in order to develop realistic models, here, we needed to perform DFT calculations with up to ∼1000 atoms. By performing full geometry relaxations at each stage, we avoid any effects of “frozen geometry” approximations. In terms of the interaction of the Pt nanoparticles with the support, we find that the surface deformation of the anatase support contributes greatly to the adsorption of each nanoparticle, especially for the anatase (001) facet. We attempt to separate geometric and electronic effects and find a larger contribution to ligand binding energy arising from the former. Overall, we show an average weakening (compared to the isolated nanoparticle) of ∼0.1 eV across atop, bridge and hollow binding sites on supported Pt55 for O and CO, and a preservation of site preference. Stronger effects are seen for O on Pt13, which is heavily deformed by anatase supports. In order to rationalize our results and examine methods for faster characterization of metal catalysts, we make use of electronic descriptors, including the d-band center and an electronic density based descriptor. We expect that the approach followed in this study could be applied to study other supported metal catalysts.
Continuity equations for electron charge densities and current densities induced in molecules by electric and magnetic fields
Authors: Lazzeretti Paolo
Published: September 2019

A series of relationships proving that the stationary current density JB(r), induced by a homogeneous time-independent magnetic field B in the electrons of diamagnetic atoms and molecules, is divergenceless are reported, assuming the conventional partition into diamagnetic and paramagnetic contributions and within the representations referred to as CTOCD (continuous translation of the origin of the current density). The continuity equations involving partial time derivatives of the dynamic polarization charge density ρ(1)(r, ω) and divergence of the current density J(1)(r, ω), induced in a molecule by a monochromatic plane wave of frequency ω, obtained by first-order time-dependent quantum mechanical perturbation theory, are investigated supposing that the wavefunctions of the ground and excited states are either real or complex. It is found that these continuity equations are satisfied by the exact eigenfunctions of a model Hamiltonian and by variationally optimal wavefunctions, for which hypervirial theorems are assumed to be valid. They are expected to hold only approximately in calculations using the algebraic approximation, with increasing accuracy for extended high-quality basis sets.
Oral administration of whole dihomo-γ-linolenic acid-producing yeast suppresses allergic contact dermatitis in mice
Authors: Watanabe Naoko , Teradu Soichiro , Ohtani Masashi , Uemura Hiroshi
Published: September 2019

Dihomo-γ-linolenic acid (DGLA, C20: 3n-6) is known to have an anti-inflammatory activity, but its range of effects was not well studied because of its limited natural sources. We addressed these issues by constructing an yeast Saccharomyces cerevisiae strain having a complete metabolic pathway for DGLA synthesis by introducing two desaturase and one elongase genes to convert endogenous oleic acid to DGLA. Taking advantage of well-known safety of S. cerevisiae, we previously investigated the efficacy of heat-killed whole DGLA-producing yeast cells on irritant contact dermatitis, and showed that oral intake of this yeast significantly suppressed inflammatory reactions, whereas no such suppression was observed by the intake of 25 times the amount of purified DGLA. Since this method is considered to be a simple and efficient way to suppress inflammation, we examined its effectiveness against allergic contact dermatitis (ACD) in this study and showed that this method was also effective against ACD.
The PI(4)P phosphatase Sac2 controls insulin granule docking and release
Authors: Nguyen Phuoc My , Gandasi Nikhil R. , Xie Beichen , Sugahara Sari , Xu Yingke , Idevall-Hagren Olof
Published: September 2019

Insulin granule biogenesis involves transport to, and stable docking at, the plasma membrane before priming and fusion. Defects in this pathway result in impaired insulin secretion and are a hallmark of type 2 diabetes. We now show that the phosphatidylinositol 4-phosphate phosphatase Sac2 localizes to insulin granules in a substrate-dependent manner and that loss of Sac2 results in impaired insulin secretion. Sac2 operates upstream of granule docking, since loss of Sac2 prevented granule tethering to the plasma membrane and resulted in both reduced granule density and number of exocytic events. Sac2 levels correlated positively with the number of docked granules and exocytic events in clonal β cells and with insulin secretion in human pancreatic islets, and Sac2 expression was reduced in islets from type 2 diabetic subjects. Taken together, we identified a phosphoinositide switch on the surface on insulin granules that is required for stable granule docking at the plasma membrane and impaired in human type 2 diabetes.
Conductive films prepared from inks based on copper nanoparticles synthesized by transferred arc discharge
Authors: Fu Qingqing , Stein Matthias , Li Wen , Zheng Jingzhi , Kruis Frank Einar
Published: September 2019

Copper nanoparticles (NPs) are considered as a promising alternative for silver and gold NPs in conductive inks for the application of printing electronics, since copper shows a high electrical conductivity but is significantly cheaper than silver and gold. In this study, copper NPs were synthesized in the gas phase by transferred arc discharge, which has demonstrated scale-up potential. Depending on the production parameters, copper NPs can be continuously synthesized at a production rate of 1.2–5.5 g h−1, while their Brunauer–Emmett–Teller sizes were maintained below 100 nm. To investigate the suitability in electronic printing, we use ball milling technique to produce copper conductive inks. The effect of ball milling parameters on ink stability was discussed. In addition, the electrical resistivity of copper films sintered at 300 °C in reducing atmosphere was measured to be 5.4 ± 0.6 μΩ cm which is about three times higher than that of bulk copper (1.7 μΩ cm). This indicates that conductive inks prepared from gas-phase synthesized copper NPs are competitive to the conductive inks prepared from chemically synthesized copper NPs.
Measurement of isocenter alignment accuracy and image distortion of an 0.35 T MR-Linac system
Authors: Dorsch S , Mann P , Elter A , Runz A , Spindeldreier C K , Klüter S , Karger C P
Published: September 2019

For hybrid devices combining magnetic resonance (MR) imaging and a linac for radiation treatment, the isocenter accuracy as well as image distortions have to be checked. This study presents a new phantom to investigate MR-Linacs in a single measurement in terms of (i) isocentricity of the irradiation and (ii) alignment of the irradiation and imaging isocenter relative to each other using polymer dosimetry gel as well as (iii) 3-dimensional (3D) geometric MR image distortions. The evaluation of the irradiated gel was performed immediately after irradiation with the imaging component of the 0.35 T MR-Linac using a T2-weighted turbo spin-echo sequence. Eight plastic grid sheets within the phantom allow for measurement of geometric distortions in 3D by comparing the positions of the grid intersections (control points) within the MR-image with their nominal position obtained from a CT-scan. The distance of irradiation and imaging isocenter in 3D was found to be (0.8  ±  0.9) mm for measurements with 32 image acquisitions. The mean distortion over the whole phantom was (0.60  ±  0.28) mm and 99.8% of the evaluated control points had distortions below 1.5 mm. These geometrical uncertainties have to be considered by additional safety margins.
Traveling concentration pulses of bacteria in a generalized Keller–Segel model
Authors: Seyrich Maximilian , Palugniok Andrzej , Stark Holger
Published: September 2019

We formulate a Markovian response theory for the tumble rate of a bacterium moving in a chemical field and use it in the Smoluchowski equation. Based on a multipole expansion for the one-particle distribution function and a reaction-diffusion equation for the chemoattractant field, we derive a polarization extended model, which also includes the recently discovered angle bias. In the adiabatic limit we recover a generalized Keller–Segel equation with diffusion and chemotactic coefficients that depend on the microscopic swimming parameters. Requiring the tumble rate to be positive, our model introduces an upper bound for the chemotactic drift velocity, which is no longer singular as in the original Keller–Segel model. Solving the Keller–Segel equations numerically, we identify traveling bacterial concentration pulses, for which we do not need a second, signaling chemical field nor a singular chemotactic drift velocity as demanded in earlier publications. We present an extensive study of the traveling pulses and demonstrate how their speeds, widths, and heights depend on the microscopic parameters. Most importantly, we discover a maximum number of bacteria that the pulse can sustain—the maximum carrying capacity. Finally, by tuning our parameters, we are able to match the experimental realization of the traveling bacterial pulse.
Higher amounts of loophole-free Bell violation using a heralded entangled source
Authors: Zhao Shuai , Cao Wen-Fei , Zhen Yi-Zheng , Chen Changchen , Li Li , Liu Nai-Le , Xu Feihu , Chen Kai
Published: September 2019

Loophole-free Bell non-locality test plays a central role in device-independent quantum information processing tasks, such as device-independent quantum random number generation (QRNG) and quantum key distribution (QKD). Inspired by the scheme of heralded spontaneous parametric down conversion (SPDC) source proposed in (Śliwa C and Banaszek K 2003 Phys. Rev. A 67 030101), we present a loophole-free Bell test scheme that employs the heralded type of entangled photon pairs. Our proposal enables a much higher degree of Bell violation with realistic photonic devices over the one using the conventional SPDC source, thus allowing the implementation of device-independent QRNG and QKD with significant advantages. We anticipate that the scheme will enable variously subtle applications in device-independent quantum information processing tasks.
Methodical review of the literature referred to the dye-sensitized solar cells: Bibliometrics analysis and road mapping
Authors: Qadir Karwan Wasman , Zafar Qayyum , Ebrahim Nader Ale , Ahmad Zubair , Sulaiman Khaulah , Akram Rizwan , Nazeeruddin Mohammad Khaja
Published: September 2019

This study presents a systematic review of the literature pertaining to dye-sensitized solar cells (DSSCs), in order to anticipate the direction and speed of change in technology trend. To study the general progression in DSSC research, we have assessed the evolution in annual DSSCs publications and their citations. Further, in order to identify the intellectual bases, we have also classified the journals, authors, institutes, and countries according to their scientific productivity in the field of DSSCs research during the period of 2007–2017.
Nb-based Josephson parametric amplifier for superconducting qubit measurement*
Authors: Su Fei-Fan , Wang Zi-Ting , Xu Hui-Kai , Zhao Shou-Kuan , Yan Hai-Sheng , Yang Zhao-Hua , Tian Ye , Zhao Shi-Ping
Published: September 2019

We report a fabrication process and characterization of the Josephson parametric amplifier (JPA) for the single-shot quantum state measurement of superconducting multiqubit system. The device is prepared using Nb film as its base layer, which is convenient in the sample patterning process like e-beam lithography and film etching. Our results show that the JPA has a bandwidth up to 600 MHz with gain above 15 dB and noise temperature approaching the quantum limit. The qubit state differentiation measurements demonstrate the signal-to-noise ratio around 3 and the readout fidelity above 97% and 91% for the ground and first-excited states, respectively.
Analytic solutions for generalized

PT

-symmetric Rabi models*
Authors: Dong Yuanhao , Zhang Wen-Jing , Liu Jing , Xie Xiao-Tao
Published: September 2019

We theoretically investigate the exact solutions for generalized parity–time(

P
T

)-reversal-symmetric Rabi models driven by external fields with monochromatic periodic, linear, and parabolic forms, respectively. The corresponding exact solutions are presented in terms of the confluent Heun equations without any approximation. In principle, the analytic solutions derived here are valid in the whole parameter space. Such a kind of study may offer potential coherent control schemes of the

P
T

-symmetric two-level systems.
Spherical Valve Stability during Hydrodynamic Closure Process
Authors: Zhang Fei , Fu Jing , Liu Dianhai , Wang Shunjun
Published: September 2019

Normally in pump-storage power plant, spherical valve is installed in the terminal of penstock. Spherical valve is used to block the water flow or involving in regulation guarantee. The stability of spherical valve is of great importance for safe operation of pump-storage power plant and unit. In this literature, two kinds of implementation for spherical valve hydrodynamic closure method were discussed, and comparisons of methods were made. On the emphasis of safety, method of shut-down unit was employed for the case pump-storage power unit. For data achieved in hydrodynamic closure with rated load, characteristic analysis of time domain and spectrum analysis of frequency domain were used. The research indicates that on the guide vane failure with load the spherical valve can effectively block water passing passage and the spherical valve displacement meets the requirement of safe running. The maximum pressure pulsation and vibration happens at the spherical valve opening of 34%. Many frequencies occurred in the pressure and vibration signals, including frequencies of rotational stall and rotor stator interference frequency. Considering on the severe vibration of spherical valve, it is recommended that the spherical valve should not involve in the regulation guarantee so as to keep the power plant safety.
Correction of the Artificial Influence on Dredging Volume in the Yangtze Estuary Deep-water Channel
Authors: Liu Meng , Zhang Hong-wei
Published: September 2019

The artificial influence on dredging volume in the Yangtze Estuary Deep-water Channel is significant and complicated. By studying the relationship between daily average dredging volume and daily average residual shallow point volume, the evaluating standard and correcting method of the artificial influence on dredging volume is successfully put forward, and the key technical gap is filled. The corrected results show that: 1) The artificial influence measures are the effective ways to adjust dredging volume, and the dredging volume per year is gradually stabilized in a region with a relatively low volume and a significantly reduced range.2)The channel quality is different each year, the dredging volume of the channel is reduced by the artificial influence but the channel quality is also reduced.3) Since the Yangtze estuary deep water channel was opened, the decline trend of the annual silting intensity in the Nangang-yuanyuansha channel has been significant, but the tendency variation of the annual silting intensity in the North Channel, as the main object of research and improvement on sedimentation reduction, is not declining, which is actually a little bit increasing.
Modelling the Hydrologic Impacts of the Nanting River Regulation and On-site Validation in the Mengding Urban Area, China-Myanmar
Authors: Ji Yong-xing , Han Fei-fei , Zhang Jian-lin , Yin Yue , Song Chen
Published: September 2019

The Nanting River runs through China and Myanmar, which has been planned to be renovated as the urban river of Mengding City, Yunnan. In order to make the river regulation works more efficient, different river discharges are tested in the 1-D and 2-D numerical models to investigate the variation of river hydrology and local flow field profiles before and after the construction works. The results are used to validate the feasibility of designed river parameters (including the width and the depth) and assess the correlation impacts. It proves that: 1) The Nanting River is a typical southern mountain river, of which the discharge has a great difference between rainy and dry seasons. The waterscape and flood control capability of different discharges should be considered for both ecological environment and flood control safety. 2) 1-D model is benchmarked against the on-site measurement data. The results indicate that 1-D model has the capability to simulate the hydrological characteristics before and after the regulation works and represent the influence of upstream and downstream flow. The results can be used as the boundary conditions in the 2-D model. 3) The simulations of the local flow field with different flow discharges are carried out by a 2-D numerical model. Those results are used for the assessments of the project layout and the revetment protection. 4) During the implementation of the regulation works, this project experienced the extreme flood which was close to the defense limit. Moreover, an earthquake and several floods hit this region. The structures survived and maintained in good condition in the hazards which proves that this regulation project is successful and necessary and the research method is valid and efficient.
Transient Process inversion calculation and extreme condition prediction of large pump turbine based on field test
Authors: Li Gaohui , Zhou Tianchi , Yu Xuesong , Yao Minjie
Published: September 2019

An innovative closing law, blocked for a while and then one segment linear closing, was investigated in a pump storage power station. It can mitigate the maximum pressure of the spiral case and the minimum pressure of the draft tube during load rejection. Problems also exist such as long load rejection process, intense unit vibration, large amplitude of the fluctuating pressure, large noise in the field. Considering the fluctuating pressure is significant in pump turbine, segmental correction method was proposed in order to guarantee the pressure inversion accurate. Field test under load rejection and hydraulic disturbance condition were conducted, proving that the fluctuating pressure is larger. The changing law of the fluctuating pressure was also obtained. The numerical result under the same condition agreed well with the test value, verifying the reliability of the numerical calculation. Numerical calculation was analysed under the extreme condition which is not suitable for field test. The result was corrected and then compared with the design value, checking the safety of the water conveyance system. The study provides reference for other pump storage power station.
Exploration on Big Data Architecture and its Correlation Analysis for Safety Monitoring in Operation of Basin’s Hydro-junctions
Authors: Li Shuangping , Liu Zuqiang , Zheng Min , Wang Huawei
Published: September 2019

In order to promote the application of big data analysis technology in the safety management in operation of basin’s hydro-junctions, the concept of big data and the “5V” characteristics are briefly described in this paper, which explains all the basic characteristics of monitoring data with big data. At the first time, it is proposed that the big data for safety monitoring in operation of basin’s hydro-junctions is composed of four dimensions: monitoring data of survey, design and construction, real-time monitoring data during operation and maintenance period, management data in operation and maintenance of dams and social resource data. The general relationship between the various factors of monitoring data, and the classification, process and mining method of correlation analysis for monitoring big data are analyzed. The method of analyzing the safety monitoring data in operation of basin’s hydro-junctions has been broadened, which meets the needs of the information and intelligence in management and operation of basin’s hydro-junctions.
Multi-objective optimization pollination algorithm based on game theory for joint dispatching of basin reservoir group
Authors: Wang Runying
Published: September 2019

In order to solve the multi-objective joint dispatching problem of watershed and reservoir, and overcome the shortcoming of single element heuristic intelligent algorithm, based on the analysis of the convergence, stability and applicability of the algorithm, an Improved Flower Pollination Algorithm (IFPA) combined with the reality of basin reservoir group is proposed. In IFPA, the elements in traditional Flower Pollination Algorithm (FPA) and the basic elements in game theory are mapped one by one. Two strategies (initializing the pollen operator with chaotic sequence and inverse learning transforming the population) are introduced into traditional FPA respectively and are gamed to optimize the problem. Function tests show that the convergence speed and optimization accuracy of IFPA are 15% and 10% higher than those of the traditional FPA respectively. IFPA is applied to the basin reservoir group dispatching and the actual dispatching results are consistent with the related literature. The study shows that IFPA is superior to the traditional FPA and can be used in multi-objective problem group joint dispatching of basin reservoir group.
Study on the Application of the Drainage Pipe Network and River Channel Coupling Model in Urban Flood Control and Drainage
Authors: Gu Chenxia
Published: September 2019

Based on the one-dimensional channel conservancy model, this paper considers the factor of urban pipe network drainage, and couples the pipe network model with the one-dimensional channel conservancy model to fully analyse the interaction between the channel water level and the drainage pipe network displacement. Taking a coastal city as an example, the model simulation results show that when the water level of the river is high, it will cause the drainage of the pipe network; the lower part of the terrain will become waterlogged because of the aging of the urban pipe and rainstorm. It is impossible to effectively solve the problem of flood control and drainage by widening the river channel. It is necessary to adopt the coordinated improvement of the pipe network and the river channel to achieve effective targets.
Analysis of the confined water of dam foundation in one water resource project
Authors: Wang Qiguo , Hu Kunsheng , Fu Jianjun , Cheng Fangquan , Chen Lianjun
Published: September 2019

Bedrock-confined water is distributing at the riverbed and the right bank of the one dam foundation. According to the preliminary analysis, it has been found that there are some confined water aquifers which appear along the rock’s fractures and the foliation planes in the dam site. The confined water has some negative influences on the dam and tunnel project because of the water head. Much attention should be paid to this and an engineering treatment needs to be taken.
Durability rehabilitation and promotion of reinforced concrete structures in tidal and splash range of deteriorated wharfs in marine environment
Authors: Wu Ye , Zhang Jie , Li Senlin , Feng Longhai , Jiang Chao
Published: September 2019

Corrosion deterioration of reinforced concrete structures in tidal and splash range has always been an urgent concern of scientific researchers and wharf managers, especially for that serving for more than 20 years in marine environment. Through on-site detection and chemical analysis, it has been found that reinforced structures in tidal and splash range of a passenger terminal in Zhoushan city suffer severe corrosion destructions such as rust expansion of steel bars, concrete cracking and spalling due to technical conditions at the initial stage of construction and insufficient awareness of durability. Meanwhile, chloride content near the surface of steel bars in concrete exceeds the critical corrosion value. In order to rehabilitate and improve the durability of reinforced concrete structures in tidal and splash range of this wharf, a combined programme of partial consolidation and electrochemical desalination is proposed and applied, which shows good performances and ensures the service life of the structure as long as possible.
The Influence of Groundwater Level Rise on Bearing Capacity of Sand Foundation
Authors: Lizhu Ma , zhonghua Zhao , Yue Tian
Published: September 2019

Along with the development of city construction, the underground space is exploited widely. This paper simulated the natural basement in sandy foundation by the way of laboratory test. Then through the SLT test we will get the change laws of bearing capacity, porewater pressure, effective stress and settlement in sandy foundation after analyzing change of underground water level. These may provide reference for the engineering application.
Study on the Cultivation of Industrial Clusters in characteristic Towns in Western China–– using the cultivation of TCM industry cluster in Taicun town, Xianyang city, Shaanxi province as an example
Authors: Xiaoyuan Zhou , Kewei Liu , Dan Zhao , Yonghui Cheng , Yuan Lv
Published: September 2019

Through studying the basic characteristics of the industrial development of small towns in western China, this paper analyses the following: the industrial selection characteristics of characteristic small towns in western China, the industrial cultivation process of characteristic small towns in western China, the subjective and objective conditions of industrial cluster composition, and the internal and external factors affecting the composition of industrial clusters. Using the cultivation of the Taicun town industrial cluster in Xianyang city, Shaanxi province, as an example, this paper discusses the methods and paths to promote the development of characteristic small towns through the selection and cultivation of characteristic industries.
Optimizing and Monitoring Measurement of Single Tunneling Outlet Scheme for Three-lane Large Cross-section Tunnel
Authors: Nie Yuwen , Guo Hongyan , Cui Xiangyang , Li Ke , Ding Hao
Published: September 2019

For a three-lane tunnel with large cross-section and one-way excavation, it is of great significance to select a reasonable scheme of entering and leaving the tunnel for the economy, safety and protection of the ecological environment of the tunnel construction. Taking Changshanpu No. 2 Tunnel as an example, the reasons for the optimization of the tunnel section are analyzed, the advantages of the optimization scheme are discussed, and the reasonable scheme is given. Through the numerical simulation of the outlet section, the monitoring data of the top of the tunnel and the analysis of the comprehensive index, it is concluded that the previous double-sided wall method is optimized to three-step temporary inverted arch method at 30m away from the outlet of the tunnel, which has the following advantages: (1) the construction space is large, the mechanical operation is convenient, the construction progress is accelerated, and the schedule requirements are met; (2) the construction of the temporary construction facilities and the large excavation in tunnel outlet section are avoided; (3) The method of three-step temporary inverted arch can be separately closed into rings, effectively restraining the deformation of surrounding rock, and the monitoring measurement meets the requirements. Therefore, the use of three-step temporary inverted arch method can improve the safety and efficiency of such highway tunnel construction, and provide a reference for future construction.
Study on Key Steps of Three-lane Weak Surrounding Rock Tunnel Construction
Authors: Wang Chao , Guo Hongyan , Cui Xiangyang , Li Ke , Ding Hao
Published: September 2019

For tunnel excavation with poor stability of surrounding rock, controlling the construction of key steps in each construction method is of great significance to tunnel construction. Taking Fengshuao and Daping tunnels as examples, this paper uses FLAC software to simulate three construction methods, i.e. double sides heading tunnel method, three-step method and CRD method. Through the analysis of displacement deformation in the numerical simulation results of three construction methods, it is concluded that the corresponding steps of maximum displacement deformation in different construction methods are the key steps in construction: the both sides heading method needs to strictly control the excavation of double-sided upper steps, the excavation of inverted arch and the dismantlement of middle-wall; the three-step method mainly controls the excavation of curved guide tunnel of upper steps, the excavation of inverted arch and the strike of locked bolts. The control steps of CRD method are the excavation of upper steps on the left wall, the excavation of upper steps on the right wall and the dismantlement of the middle wall. Therefore, strictly controlling the key steps of each construction method can improve the safety and efficiency of this kind of highway tunnel construction, and provide reference for future construction.
Research on the Construction of Humanistic Airport
Authors: Li Xiong
Published: September 2019

Humanistic airport is an important part of the construction objectives of “four types of airports”, namely safe airport, green airport, intelligent airport and humanistic airport. The construction of humanistic airport puts forward higher requirements for airport planning, design and operation management, emphasizing people-oriented and paying attention to passenger travel experience. The connotation, characteristics and problems in current planning, design and management of humanistic airports were analyzed. Drawing lessons from successful cases at home and abroad, this paper put forward suggestions and measures for the construction of China’s humanities airport.
Research on Tunnel Lining Cavity Treatment Technology of a Metro Tunnel in Chongqing
Authors: Hu Xuebing , Jiang Xinghong , Li Ke , Cui Xiangyang
Published: September 2019

The hollowing problem of tunnel lining structure is like a suspended bomb, which may affect the safety of vehicles and the safety of passengers at any time. Therefore, the study of tunnel lining structure cavity management technology has great social significance for ensuring tunnel safety. Taking a metro tunnel in Chongqing as an example, this paper proposes a reasonable lining structure reinforcement scheme of changing partial arches and reinforcing by steel strips after analyzing the environment, the bearing requirements, and the size and location of cavities. Based on the calculation formula of flexural members given by Code for Design of Concrete Structure Reinforcement, reduction system is introduced to calculate safety coefficient of flexural and compression members. The minimum value of structural bearing after treatment is 4.4, which meets the requirement of bearing capacity. Stratum structure method is used to calculate surrounding rock deformation during reinforcement. The maximum horizontal displacement is 1.9 mm, and the vertical displacement is 6 mm. The surrounding rock could be stable when treating defects, and the treatment scheme meets the requirements of bearing capacity and inner clearance. Therefore, the tunnel lining structure cavity can be reinforced by means of shotcrete and steel strips, without interrupting traffic and ensuring driving safety. The success of the treatment provides a useful reference for other similar projects.