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Journal articles on the topic 'Rör installation'
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Wiśniewska, Marta, and Krystyna Lelicińska-Serafin. "The Role and Effectiveness of the MBT Installation in Poland Based on Selected Examples." Civil and Environmental Engineering Reports 29, no. 2 (June 1, 2019): 1–12. http://dx.doi.org/10.2478/ceer-2019-0011.
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Abstract The paper presents examples of installations for the mechanical and biological treatment of municipal waste in Poland. Each of the presented installations is defined as a regional municipal waste treatment installation (RIPOK). Their technological solutions and work efficiency have been compared in this study. In addition, the loss of waste mass as a result of processes occurring in the biological part of individual installations was calculated in the research. The paper refers to the National Waste Management Plan (KPGO 2022) regarding the circular economy. As intended by the circular economy, MBP installations will be transformed into installations that will treat selectively collected municipal waste and become Regional Recycling Centers (RCR).
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崔, 晓东. "Installation and Construction of Threaded RTR Pipe." Journal of Oil and Gas Technology 43, no. 03 (2021): 236–44. http://dx.doi.org/10.12677/jogt.2021.433056.
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M.R., Kabit, Sabihin N.A., and Wan Ibrahim W.H. "EFFECTIVENESS OF AUTOMATED ENFORCEMENT SYSTEM (AES) IN REDUCING RED LIGHT VIOLATION (RLV) BEHAVIOURS: A CASE STUDY IN KUALA LUMPUR." Journal of Civil Engineering, Science and Technology 7, no. 1 (April 1, 2016): 39–44. http://dx.doi.org/10.33736/jcest.154.2016.
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The national statistics indicates that red light violations (RLV) have become a significant safety problem throughout the nation. As a result, the Malaysian government has initiated the installation of automated enforcement system (AES) to reduce RLV related crashes at identified critical locations particularly in Kuala Lumpur region. The primary aim of this study was to evaluate the effectiveness of AES installation in reducing RLR at signalised intersections using a case study at Jalan Ipoh, Kuala Lumpur. Before and after AES installation data were collected and were analysed using a statistical tool. T-test results indicated that the installation of AES has significantly reduced RLV behaviours at the studied signalised intersection. The results of this study provide a useful insight on the benefits of AES in decreasing intersection related crashes by means of reducing RLV behaviours among the road users through AES installation.
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Pauliat, Hélène. "Installation des crèches dans un emplacement public : des critères flous." Revue du droit des religions, no. 4 (October 31, 2017): 67–82. http://dx.doi.org/10.4000/rdr.692.
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Makushkin, I. E., A. M. Shemarin, Yu Yu Vitsukaev, and D. M. Tyurin. "A method for measuring boresight errors for a radioparent radome of arbitrary shape." Journal of «Almaz – Antey» Air and Defence Corporation, no. 1 (March 30, 2020): 26–45. http://dx.doi.org/10.38013/2542-0542-2020-1-26-45.
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The previously presented method for measuring and calculating the components of boresight angle errors (BAE) in the “antenna – radioparent radome (RPR)” system in the two-dimensional angular scanning area of the antenna with electronic beam control, which includes a phased-array antenna (PAA), was tested in relation to a system with a drop-shaped radome. Measurements were carried out using an antenna measuring collimator complex (“compact polygon”) with a complex drop-shaped RPR and PAA installed thereunder. To create a BAE matrix on the surface of the RPR, measurements and subsequent calculations were performed at different “roll” angles of the antenna-radome system and different deflection angles of the PAA beam in “oblique planes”. The BAE measurements carried out in several RPR surface sections by the proposed method, show a good reproducibility and correlate well with the results of BAE measurements carried out using the same sections by the conventional difference method, where the BAE component is calculated as the difference between the angular coordinates of the minima of the corresponding PAA tracking pattern (TP), before and after the RPR installation.
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Lyon, Craig, Bhagwant Persaud, and Eric Donnell. "Safety Evaluation of the SafetyEdge Treatment for Pavement Edge Drop-Offs on Two-Lane Rural Roads." Transportation Research Record: Journal of the Transportation Research Board 2672, no. 30 (March 15, 2018): 1–8. http://dx.doi.org/10.1177/0361198118758054.
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This study estimated crash modification factors (CMFs) for the SafetyEdge paving technique that is applied for the treatment of pavement edge drop-offs on two-lane rural highways. An empirical Bayes observational before-after evaluation based on installation data in Iowa, North Carolina, Ohio, Pennsylvania, and Florida found that the SafetyEdge treatment was associated with statistically significant reductions in fatal and injury (FI), run-off-the-road (ROR), opposite-direction (head-on and sideswipe), and drop-off-related crashes. The ROR CMF was also statistically significant for both horizontal curved and tangent sections. A disaggregate analysis examined the variation of the CMF for ROR with factors such as the travel lane width, traffic volume, presence of a horizontal curve, posted speed limit, and the pre-treatment ROR crash frequency. The results of that analysis indicated, for example, that the SafetyEdge paving technique appears to have a greater ROR safety benefit on two-lane rural roadway segments with average annual daily traffic volumes greater than 3,000 vehicles per day, relative to roadway segments with lower traffic volumes. A crash modification function (CMFunction) was calibrated with expected pre-treatment ROR crashes as the independent variable to simultaneously capture the relationship of the CMF for ROR crashes to multiple factors. An economic analysis found that the treatment is highly cost-effective.
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Oleńczuk-Paszel, Anna, and Agnieszka Sompolska-Rzechuła. "Zmiany warunków mieszkaniowych na obszarach wiejskich w Polsce w latach 2002-2014." Roczniki Naukowe Ekonomii Rolnictwa i Rozwoju Obszarów Wiejskich 104, no. 2 (August 15, 2017): 87–97. http://dx.doi.org/10.22630/rnr.2017.104.2.15.
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The aim of the study was to determine the regularities of the dynamics of living conditions in rural areas in the conteXt of Poland. The features concerning the eXisting dwelling stocks, buildings and dwellings completed as well as dwellings fitted with basic installation were analyzed in the study. The empirical part of the research was described using data from the study “Rural areas in Poland in 2014” by GUS. The study covered the period 2002-2014. All features included in the study showed a favorable trend, which proves that the living conditions of inhabitants of rural areas have been improving.
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Aslam, Muhammad, Jae-Myeong Lee, Hyung-Seung Kim, Seung-Jae Lee, and Sugwon Hong. "Deep Learning Models for Long-Term Solar Radiation Forecasting Considering Microgrid Installation: A Comparative Study." Energies 13, no. 1 (December 27, 2019): 147. http://dx.doi.org/10.3390/en13010147.
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Microgrid is becoming an essential part of the power grid regarding reliability, economy, and environment. Renewable energies are main sources of energy in microgrids. Long-term solar generation forecasting is an important issue in microgrid planning and design from an engineering point of view. Solar generation forecasting mainly depends on solar radiation forecasting. Long-term solar radiation forecasting can also be used for estimating the degradation-rate-influenced energy potentials of photovoltaic (PV) panel. In this paper, a comparative study of different deep learning approaches is carried out for forecasting one year ahead hourly and daily solar radiation. In the proposed method, state of the art deep learning and machine learning architectures like gated recurrent units (GRUs), long short term memory (LSTM), recurrent neural network (RNN), feed forward neural network (FFNN), and support vector regression (SVR) models are compared. The proposed method uses historical solar radiation data and clear sky global horizontal irradiance (GHI). Even though all the models performed well, GRU performed relatively better compared to the other models. The proposed models are also compared with traditional state of the art methods for long-term solar radiation forecasting, i.e., random forest regression (RFR). The proposed models outperformed the traditional method, hence proving their efficiency.
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Basu, Urbi, and Christine A. Powell. "Velocity and azimuthal anisotropy structure underneath the Reelfoot Rift region from Rayleigh wave phase velocity dispersion curves." Geophysical Journal International 228, no. 1 (August 23, 2021): 291–307. http://dx.doi.org/10.1093/gji/ggab337.
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SUMMARY Phase velocity and azimuthal anisotropy maps for fundamental mode Rayleigh waves are determined for a portion of the central United States including the seismically active Reelfoot Rift (RFR) and the enigmatic Illinois Basin. Dense seismic array installations of the Northern Embayment Lithosphere Experiment, the EarthScope transportable array and the Ozarks Illinois Indiana Kentucky array allow a detailed investigation of phase velocity and anisotropy in a broad period range (20–100s).We obtain more than 12 000 well-constrained, unique two-station paths from teleseismic events. The two-station method is used to determine dispersion curves and these are inverted for isotropic phase velocity maps and azimuthal anisotropy maps for each period. The presence of fast phase velocities at lower crustal and uppermost mantle depths is found below the RFR, and Ste. Genevieve and Wabash Valley fault zones. At periods of 30s and higher, the RFR is underlain by slow phase velocities and is flanked to the NW and SE by regions of fast velocity. Fast phase velocities are present below the centre of the Illinois Basin in the period range 75–100s. Anisotropy fast axis orientations display complex patterns for each period and do not trend parallel to the direction of absolute plate motion. Anisotropy fast directions are consistently parallel to the trend of the RFR from 50s to higher periods, suggesting the presence of either frozen-in anisotropic fabric or fabric related to material transport from a recently discovered, pronounced low velocity zone below the Mississippi Embayment.
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Kamajati, Dhatu, Heri Syaeful, and Mirna Berliana Garwan. "Evaluasi Massa Batuan Terowongan Eksplorasi Uranium Eko-Remaja, Kalan, Kalimantan Barat." EKSPLORIUM 37, no. 2 (December 19, 2016): 89. http://dx.doi.org/10.17146/eksplorium.2016.37.2.3110.
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ABSTRAKTerowongan eksplorasi uranium Eko Remaja, Kalan, Kalimantan Barat merupakan salah satu sarana penelitian cebakan uranium yang sangat penting. Terowongan ini dibangun tahun 1980 dengan panjang 618 meter dan menembus Bukit Eko di kedua sisinya. Batuan di terowongan ini relatif kompak, tetapi memiliki zona lemah di beberapa bagiannya. Penyanggaan merupakan metode yang digunakan untuk menanggulangi keruntuhan tanah dan batuan yang terjadi pada zona lemah di terowongan. Pemasangan penyangga yang selama ini dilakukan berdasarkan pola keruntuhan yang terjadi pada saat pembukaan terowongan tanpa melalui studi khusus menyangkut karakterisasi massa batuan dan kebutuhan sistem penyangga. Penelitian ini dilakukan untuk mengevaluasi tingkat keselamatan terowongan Eko-Remaja dan kesesuaian lokasi penyangga. Evaluasi dilakukan dengan membandingkan karakteristik massa batuan menggunakan metode Rock Mass Rating (RMR) antara lokasi penyangga batuan terpasang dan lokasi penyangga batuan tidak terpasang. Berdasarkan hasil analisis, nilai RMR pada lokasi terpasang penyangga diklasifikasikan ke dalam kelas IV atau batuan buruk. Sementara itu, di lokasi tidak terpasang penyangga batuan diklasifikasikan ke dalam kelas II atau batuan baik. Berdasarkan korelasi antara hasil perhitungan RMR dengan roof span terowongan Eko-Remaja disimpulkan bahwa posisi penyanggaan terowongan yang diwakili oleh lokasi pengamatan pada kedalaman 38 m, 73 m, dan 165 m sudah sesuai dengan sistem karakterisasi massa batuan menggunakan metode RMR. ABSTRACTEko-Remaja uranium exploration tunnel, Kalan, West Kalimantan is one of the important facilities for uranium deposit research. The tunnel was built in 1980 with a length of 618 meters penetrating Eko Hill on both sides. The rock inside the tunnel is relatively compact, but it has weak zones in some area. Ground supporting is a method used to overcome the soil and rock collapses which occurred in the tunnel weak zones. Installation of ground supporting system throughout the recent time based on the soil collapse pattern, which occurred when the tunnel opened without any specific study related to rock mass characterization and the requirement of ground support system. This research conducted to evaluate the safety level of Eko-Remaja tunnel and the suitability of ground support location. The evaluation performed by comparing the rock mass characteristics using Rock Mass Rating (RMR) method between the installed rock support and uninstalled rock support locations. Based on the analysis result, RMR value on the installed ground support is classified as class IV or poor rock. Meanwhile, on uninstalled location, the rock is classified as class II or fair rock. Based on the correlation between RMR calculation result and Eko-Remaja tunnel roof span, it is concluded that tunnel ground supports position which are represented by observation location on 38 m, 73 m, and 165 m depth are suitable with rock mass characterization system using RMR method.
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Liu, Bin, Yuanguang Zhu, Quansheng Liu, and Xuewei Liu. "A Novel in Situ Stress Monitoring Technique for Fracture Rock Mass and Its Application in Deep Coal Mines." Applied Sciences 9, no. 18 (September 7, 2019): 3742. http://dx.doi.org/10.3390/app9183742.
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A novel in situ stress monitoring method, based on rheological stress recovery (RSR) theory, was proposed to monitor the stress of rock mass in deep underground engineering. The RSR theory indicates that the tiny hole in the rock can close gradually after it was drilled due to the rheology characteristic, during which process the stress that existed in the rock can be monitored in real-time. Then, a three-dimensional stress monitoring sensor, based on the vibrating wire technique, was developed for in field measurement. Furthermore, the in-field monitoring procedures for the proposed technique are introduced, including hole drilling, sensor installation, grouting, and data acquisition. Finally, two in situ tests were carried out on deep roadways at the Pingdingshan (PDS) No. 1 and No. 11 coal mines to verify the feasibility and reliability of the proposed technique. The relationship between the recovery stress and the time for the six sensor faces are discussed and the final stable values are calculated. The in situ stress components of rock masses under geodetic coordinates were calculated via the coordinate transformation equation and the results are consistent with the in situ stress data by different methods, which verified the effectiveness of the proposed method.
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Zeb, Kamran, Saif Ul Islam, Waqar Ud Din, Imran Khan, Muhammad Ishfaq, Tiago Davi Curi Busarello, Iftikhar Ahmad, and Hee Je Kim. "Design of Fuzzy-PI and Fuzzy-Sliding Mode Controllers for Single-Phase Two-Stages Grid-Connected Transformerless Photovoltaic Inverter." Electronics 8, no. 5 (May 9, 2019): 520. http://dx.doi.org/10.3390/electronics8050520.
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Conventional Energy Resources (CER) are being rapidly replaced by Renewable Energy Resources (RER) due to their abundant, environmentally friendly, clean, and inexhaustible nature. In recent years, Solar Photovoltaic (SPV) energy installation is booming at a rapid rate among various RER. Grid-Connected PVS required advance DC-link controllers to overcome second harmonic ripple and current controllers to feed-in high-quality current to the grid. This paper successfully presents the design of a Fuzzy-Logic Based PI (F-PI) and Fuzzy-Logic based Sliding Mode Controller (F-SMC) for the DC-link voltage controller and Proportional Resonant (PR) with Resonant Harmonic Compensator (RHC) as a current controller for a Single-Phase Two-Stages Grid-connected Transformerless (STGT) Photovoltaic (PV) Inverter. The current controller is designed with and without a feedforward PV power loop to improve dynamics and control. A Second Order General Integral (SOGI)-based Phase Lock Loop (PLL) is also designed that has a fast-dynamic response, fast-tracking accuracy, and harmonic immunity. A 3 kW STGT-PV system is used for simulation in Matlab/Simulink. A comparative assessment of designed controllers is carried out with a conventionally well-tuned PI controller. The designed controllers improve the steady-state and dynamic performance of the grid-connected PV system. In addition, the results, performance measure analysis, and harmonics contents authenticate the robustness, fastness, and effectiveness of the designed controllers, related to former works.
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Dwivedi, Sunil Kumar, and Prakash Chandra Adhikary. "Engineering geology of Kankai Hydroelectric tunnel alignment." Journal of Nepal Geological Society 31 (December 4, 2006): 67–74. http://dx.doi.org/10.3126/jngs.v31i0.262.
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This paper describes the engineering geological characteristics of rock mass in the headrace tunnel, powerhouse, and intake portal of the Kankai Hydroelectric Project. The project area lies in the Lower Siwaliks of east Nepal and consists of alternating sandstone and mudstone beds with frequent siltstone intercalations. The rock mass of the project area was classified according to rock mass rating (RMR) and rock mass quality index (Q) systems. It is of very poor, poor, to fair quality (categories V, IV, and III) in the headrace tunnel; of very poor quality (category V) in the powerhouse; and of fair quality (category III) in the intake portal. The stability analysis of irregularly jointed and fractured rocks of the area was carried out using SWEDGE and UNWEDGE. The analysis gave the safety factor of 0.45, 0.64, and 0.45, respectively for the powerhouse, intake portal, and headrace tunnel. The final safety factors obtained after the installation of support for powerhouse, intake portal, and headrace tunnel were 1.14, 3.33, and 4.53, respectively.
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Faizah, Yuni, Wira Cakrabuana, Dhatu Kamajati, and Putri Rahmawati. "Analisis Kualitas dan Perkuatan Terowongan Eksplorasi Uranium Eko Remaja Kalan, Kalimantan Barat menggunakan Metode RMR (Rock Mass Rating)." EKSPLORIUM 41, no. 1 (May 30, 2020): 25. http://dx.doi.org/10.17146/eksplorium.2020.41.1.5859.
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ABSTRAK Terowongan Eksplorasi Uranium Eko Remaja Kalan (TEURK) di Kalimantan Barat yang dibangun pada tahun 1980 merupakan salah satu sarana penelitian cebakan uranium di Indonesia. Terowongan ini menembus Bukit Eko Remaja sepanjang 618 m, mulai dari pintu Remaja hingga TRK-7. Mineralisasi uranium di lokasi ini dikontrol oleh urat-urat tak beraturan (stockwork) yang sangat rapat pada batuan metalanau dan metapelit. Tingginya kerapatan struktur geologi tersebut membentuk beberapa zona lemah di dalam terowongan. Zona lemah tersebut berpotensi menyebabkan terjadinya longsor batu dan tanah. Penyangga sementara terbuat dari tiang-tiang kayu dipasang di zona tersebut untuk perkuatan terowongan. Saat ini tiang kayu tersebut tidak lagi mampu menyangga terowongan sehingga sering terjadi longsor batu dan tanah di dalam terowongan. Penelitian ini bertujuan untuk mengetahui kualitas massa batuan aktual dan menentukan jenis perkuatan yang sesuai agar terowongan tetap aman. Survei palu Schmidt dan scanline pada zona tak berpenyangga (kedalaman 50–297 m dan 355–538 m) dilakukan untuk mengambil data parameter klasifikasi Rock Mass Rating (RMR). Hasil pengukuran menunjukkan bahwa massa batuan TEURK di kedalaman tersebut memiliki nilai RMR 52-71 (sedang–baik). Perkuatan yang direkomendasikan adalah pemasangan baut batu dan beton semprot konvensional.ABSTRACT Tunnel for Exploration of Uranium Eko Remaja Kalan (TEURK) in West Kalimantan, built-in 1980, is one of the uranium deposit research facilities in Indonesia. The tunnel penetrated Eko Remaja Hill along 618 m, from Remaja to TRK-7 access. Uranium mineralization in this area controlled by dense stockwork veins on metasilt and metasandstone rocks. The high-dense geological structures create some weak zones in the tunnel. These zones are potentially causing rocks and soil slides. Temporary supports made of wood-piles were installed in these zones to support the tunnel. Currently, these piles are not capable at the tunnel, so that rocks and soil slides occurred inside the tunnel. The research aimed to determine the quality of actual rock mass and determine the appropriate type of reinforcement to keep the tunnel safe. Schmidt hammer and scanline surveys on the unsupported zone (50–297 m and 355–538 m depth) carried out to collect the classification parameter data of Rock Mass Rating (RMR). The measurement result shows that the rock mass of TEURK on the depth has an RMR value of 52–71 (fair-good). Reinforcement recommendations for the tunnel are rock bolts and conventional shotcretes installation.
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Tang, Tianpei, Senlai Zhu, Yuntao Guo, Xizhao Zhou, and Yang Cao. "Evaluating the Safety Risk of Rural Roadsides Using a Bayesian Network Method." International Journal of Environmental Research and Public Health 16, no. 7 (April 1, 2019): 1166. http://dx.doi.org/10.3390/ijerph16071166.
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Evaluating the safety risk of rural roadsides is critical for achieving reasonable allocation of a limited budget and avoiding excessive installation of safety facilities. To assess the safety risk of rural roadsides when the crash data are unavailable or missing, this study proposed a Bayesian Network (BN) method that uses the experts’ judgments on the conditional probability of different safety risk factors to evaluate the safety risk of rural roadsides. Eight factors were considered, including seven factors identified in the literature and a new factor named access point density. To validate the effectiveness of the proposed method, a case study was conducted using 19.42 km long road networks in the rural area of Nantong, China. By comparing the results of the proposed method and run-off-road (ROR) crash data from 2015–2016 in the study area, the road segments with higher safety risk levels identified by the proposed method were found to be statistically significantly correlated with higher crash severity based on the crash data. In addition, by comparing the respective results evaluated by eight factors and seven factors (a new factor removed), we also found that access point density significantly contributed to the safety risk of rural roadsides. These results show that the proposed method can be considered as a low-cost solution to evaluating the safety risk of rural roadsides with relatively high accuracy, especially for areas with large rural road networks and incomplete ROR crash data due to budget limitation, human errors, negligence, or inconsistent crash recordings.
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Gradziuk, Piotr, and Barbara Gradziuk. "Próba oceny efektów absorpcji środków z funduszy europejskich na rozwój wykorzystania odnawialnych źródeł energii w województwie lubelskim." Roczniki Naukowe Ekonomii Rolnictwa i Rozwoju Obszarów Wiejskich 104, no. 3 (December 18, 2017): 95–105. http://dx.doi.org/10.22630/rnr.2017.104.3.25.
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The paper presents results of study aimed at assessing an absorption of European Union funds intended for investments in renewable energy in the Lubelskie province. Source of the data was the Department of Regional Operational Programme in the Marshal’s Office for Lubelskie province in Lublin and the Department of European Funds in Ministry of Energy. With the funds from the Regional Operational Programme of the Lubelskie province and the Rural Development Programme (3.2.1) over 34 thousand renewable energy installations with capacity of 189,2 MWt and 4,1 MWe, were build. Most of them were solar collectors (95.8%), biomass boilers (2.3%) and photovoltaic panels (1.9%). Such significant share of solar energy projects proves the hypothesis of the Renewable Energy Development Program for the Lubelskie province that it is possible for the Lubelskie region to become a national leader in the use of solar energy for the production of heat and electricity. As a result of implemented projects the consumption of conventional fuels in rural areas dropped by around 4% per year, what is equal to the energy value of 19 thousand tons of bituminous coal. Furthermore, actions taken with the help of above mentioned programs resulted in a reduction of CO2 emissions by around 1,7 thousand tons of primary greenhouse gas, dust and other pollutants.
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Danilov, S. E., and V. L. Arbuzov. "Production of pure nickel alloys doped with sulfur and phosphorus." Diagnostics, Resource and Mechanics of materials and structures, no. 6 (December 2020): 48–53. http://dx.doi.org/10.17804/2410-9908.2020.6.048-053.
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A procedure for alloying nickel with sulfur and phosphorus by diffusion and homogenizing annealing is described using the example of pure nickel (RRR at 600). A scheme of the installation for alloying from the gas phase is described. The possibility of uniform alloying with sulfur and phosphorus of samples and material in the form of plates or foils with a thickness of 0.2 mm or thinner at a concentration ranging between 0.001 and 0.08) at. % is shown. Diffusion annealing is carried out after heating and pumping out in a high vacuum and without contamination, in a quartz volume containing sulfur or phosphorus vapors at a temperature of 1100 to 1200 °C. By choosing the ratio of the masses of the alloyed material and the corresponding filling of sulfur or phosphorus, it is possible to predict in advance the resulting concentration of impurities with a sufficient time of annealing. The impurity concentration is uniform in volume within ten percent. Modeling and control annealings with the measurement of the residual resistivity of the control samples allows you to evaluate the results obtained.
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Ha, Sang-gui, Abdul Muntaqim Naji, Hafeezur Rehaman, Kyoung-min Nam, Han-eol Kim, Jae-won Park, and Han-kyu Yoo. "Expanded Longitudinal Deformation Profile in Tunnel Excavations Considering Rock Mass Conditions via 3D Numerical Analyses." Applied Sciences 11, no. 12 (June 10, 2021): 5405. http://dx.doi.org/10.3390/app11125405.
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In the convergence–confinement method, the longitudinal deformation profile (LDP) serves as a graphical representation of the actual tunnel convergence (both ahead of and behind the face); therefore, it is considered important for determining the distance of support installation from the face or the timing after excavation in this method. The LDP is a function of the rock mass quality, excavation size, and state of in situ stresses; thus, obtaining the LDP according to the rock mass conditions is essential for analyzing the complete behavior of convergence during tunnel excavation. The famous LDP shows that the best fit for the measured values of tunnel internal displacement reported simply expresses the ratio of the preceding displacement as approximately 0.3. This can lead to an error when predicting the ratio of the preceding displacement while neglecting the rock conditions; consequently, a complete tunnel behavior analysis cannot be realized. To avoid such error, the finite difference method software FLAC 3D is used to develop an expanded longitudinal deformation profile (ELDP) according to the rock mass conditions. The ELDP is represented by graphs featuring different shapes according to the rock mass rating (RMR), and the empirical formula of the LDP best fitted for the tunnel convergence measurement values is expanded. This expanded LDP formula is proposed in a generalized form, including the parameters α and β from the empirical equation. These parameters α and β are expressed as functions of the RMR and initial stress. Statistical analysis results of the 3D numerical analysis of 35 cases were analyzed in the ranges of α = 0.898–2.416 and β = 1.361–2.851; this result is based on the empirical formula of Hoek (1999) (α = 1.1, β = 1.7), which was expanded in the current study according to the rock quality and initial stress conditions.
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Mrigua, Khalid, Abdelghani Toumi, Mounia Zemamou, Bader Ouhmmou, Yahya Lahlou, and Mohammed Aggour. "CFD Investigation of A New Elliptical-Bladed Multistage Savonius Rotors." International Journal of Renewable Energy Development 9, no. 3 (June 29, 2020): 383–92. http://dx.doi.org/10.14710/ijred.2020.30286.
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The Savonius-conventional wind turbine is a class of wind turbines designed with a vertical axis. It has a good starting capacity and an insensitivity to wind direction. It works relatively at low wind speed in an easy installation. Savonius wind turbine faces major drawbacks, including some of the low efficiency and high negative torque created by the returning blade. Many attempts have been undertaken to optimize the blade’s shape to increase the performance of these wind turbines. The vertical axis is still under development. The elliptical-blades with a cut angle equal 47.50° have recently shown enhanced performance. In this study, we investigate the effect of Elliptical-bladed multistage Savonius Rotors (rotor aspect ratio, stage aspect ratio) on the performance by means of numerical simulation. The results obtained by comparison of one, two, and three-stage rotors indicate that the maximum power coefficient increase with a number of the stages (for the rotors with similar RAR of 0.7). Moreover, for the rotors with similar SAR of 0.7, the two stages have the highest performance than others.©2020. CBIORE-IJRED. All rights reserved
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Lahmili, A., L. Ouadif, A. Akhssas, and L. Bahi. "Rock stability analysis – A case study." MATEC Web of Conferences 149 (2018): 02072. http://dx.doi.org/10.1051/matecconf/201814902072.
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The problems of the stability of the mineral-bearing structure ST2 at 560 m of depth in the east zone of Bou-azzer mine disturbs the advance of the exploitation. The geological and structural study based on field observations and the analysis of core drilling shows the presence of altered and fractured diorite surmounted by cobalt mineralization. Based on the empirical methods of Barton (Q-system) and Bieniawski (RMR) the bed rock is classified as poor quality. The analytical study made it possible to dimension supporting by bow-pieces and bolting. The existence of several types of discontinuities (fault, diaclases and joints) has made the realization of numerical simulation by the finite elements method very difficult. These discontinuities create a network of natural fractures which cut out the blocks in various forms likely to be detached or slip into the excavation, thus encouraging the infiltration of water creating pressure on the massif. The classical studies show their limits in practice for installation of supporting because they must take into account the characteristics of discontinuities. Hence a structural analysis of the massif is essential. The cracking survey of ST2 at 560 m of depth in the east zone of Bou-azzer mine at 560m of depth, and their processing by the DIPS software, showed the existence of three main families of discontinuity NW-SE with a dip of 75SW, NS subverticale and NE-SW with a dip of 57NW, and two families of minor joints NW-SE and NE-SW with successive dips of 40SW and 75SE. The analysis of fracturing surveys allowed us to evaluate the risks of falling blocks and the families of discontinuity responsible for them, and to limit the zones presenting a risk of slip and the families responsible for them. The importance of this study is of knowing how and where to put supporting to be opposed to the risk of fall and tilting of the blocks, caused by the network of discontinuities of the massif.
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Gubarev, E. I. "The prevention and treatment of myopia in schoolchildren from grade 1 to grade 10 by restoring the ocular accommodation function." Russian Ophthalmological Journal 12, no. 2 (June 12, 2019): 59–63. http://dx.doi.org/10.21516/2072-0076-2019-12-2-59-63.
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Purpose: to evaluate long term effectiveness of a method of restoring the accommodation function of the eye and preventing the onset and progression of myopia and to propose ways to overcome medical requirements that are difficult to meet.Material and methods. The method consisted in prolonged installations of 1 % tropicamide eye drops and permanent optical correction that corresponded to manifest refraction. 48 schoolchildren aged 7–18 with initial myopia or signs of high risk myopia onset were followed up. The subjects were divided into 2 groups of 24 people each. Group 1 consisted of children who followed medical prescriptions and group 2 consisted of those who did not. The two groups were further subdivided into two subgroups. Subgroup 1A included 12 children with the initial positive cycloplegic refraction up to +1.0 D; subgroup 1B included 12 children with the initial negative cycloplegic refraction from -0.5 D. Subgroup 2A (12 children) had negative cycloplegic refraction who regularly failed to receive treatment (optical correction, eyedrop instillations, medical checkups), and subgroup 2B (12 children) had negative cycloplegic refraction who received practically no treatment for myopia. Regular checkups took place 2–3 times a year for 10 years and included measuring visual acuity, manifest and cycloplegic refraction by skiascopy or subjectively, as well as measuring relative accommodation reserve (RAR) according to the author’s own technique. The treatment envisaged permanent optical correction in accordance with manifest refraction until the age of 18 years, combined with courses of tropicamide 1 % instillations for 1 to 3 months two to three times a year. Results. In group 1A, myopia was prevented in all subjects. In group 1B, the progression stopped after several years of treatment. In subgroup 2A and especially subgroup 2B, myopia progressed, over the 10-year follow-up period reaching the figures of 2.5 and 3.5 D, respectively. Conclusion. The long-term efficiency of the proposed method applied to schoolchildren from grade 1 to grade 10 was confirmed. Ways to overcome the difficulties of following medical requirements were proposed.
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Amaral Valladão, Carlos Alberto, Mabelle Freitas Monteiro, and Julio Cesar Joly. "Guided bone regeneration in staged vertical and horizontal bone augmentation using platelet-rich fibrin associated with bone grafts: a retrospective clinical study." International Journal of Implant Dentistry 6, no. 1 (October 17, 2020). http://dx.doi.org/10.1186/s40729-020-00266-y.
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Abstract Background The use of guided bone regeneration (GBR) for vertical and horizontal bone gain is a predictable approach to correct the bone defects before implant installation; however, the use of different protocols is associated with different clinical results. It is suggested that platelet-rich fibrin (PRF) could improve the outcomes of regenerative procedures. Thus, this study aimed to describe the bone gain associated with GBR procedures combining membranes, bone grafts, and PRF for vertical and horizontal bone augmentation. Materials and methods Eighteen patients who needed vertical or horizontal bone regeneration before installing dental implants were included in the study. The horizontal bone defects were treated with a GBR protocol that includes the use of a mixture of particulate autogenous and xenogenous grafts in the proportion of 1:1, injectable form of PRF (i-PRF) to agglutinate the graft, an absorbable collagen membrane covering the regenerated region, and leukocyte PRF (L-PRF) membrane covering the GBR membrane. The vertical bone defects were treated with the same grafted mixture protected by a titanium-reinforced non-resorbable high-density polytetrafluoroethylene (d-PTFE-Ti) membrane and covered by L-PRF. The bone gain was measured using a cone-beam computed tomography at baseline and after a period of 7.5 (± 1.0) months. Results All patients underwent surgery to install implants after this regenerative protocol. The GBR produces an increase in bone thickness (p < 0.001) and height (p < 0.005) after treatment, with a bone gain of 5.9 ± 2.4 for horizontal defects and 5.6 ± 2.6 for vertical defects. In horizontal defects, the gain was higher in the maxilla than in mandible (p = 0.014) and in anterior than the posterior region (p = 0.033). No differences related to GBR location were observed in vertical defects (p > 0.05). Conclusion GBR associated with a mixture of particulate autogenous and xenogenous grafts and i-PRF is effective for vertical and horizontal bone augmentation in maxillary and mandibular regions, permitting sufficient bone gain to future implant placement. Trial registration REBEC, RBR-3CSG3J. Date of registration—19 July 2019, retrospectively registered. http://www.ensaiosclinicos.gov.br/rg/RBR-3csg3j/
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Shambira, Leonard, and Memory Mandiudza. "AWARENESS AND ADOPTION OF INTELLIGENT RAILWAY TRANSPORT SYSTEM IN ZIMBABWE." European Journal of Social Sciences Studies 6, no. 2 (February 8, 2021). http://dx.doi.org/10.46827/ejsss.v6i2.997.
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The study seeks to investigate the awareness and adoption of modern technologies which are collectively called (IRTS) Intelligent Railway Transport Systems by the NRZ (National railways of Zimbabwe) of Zimbabwe. Adoption of these technologies are on an increasing trend in developed and developing countries, installation and implementation of a railway system called RailTracker in Tanzania has improved railway services in that country, in Uganda and Kenya the Rift Valley Railway (RVR) has introduced GPS technology to track trains. In India a system is used to detect defects in rolling stock while they are on the run. Where these systems have been implemented, they have significantly improved the efficiency, safety and quality of service of railway operations. In Zimbabwe the rail network is an important transport infrastructure enabling movement of goods and passengers. Primary research was carried out using questionnaires and semi structured interviews, data was collected from 67 participants comprising Engineers, Technicians, Train Drivers and Station Managers. 98% of the technical participants indicated that they were aware of IRTS however the adoption of the systems by the NRZ is at 0%. 100% of the Managers indicated that they were aware of IRTS and the company is willing to adopt them but currently no system has been installed Secondary research was conducted to identify and study similar projects elsewhere, their success as well as the difficulties encountered during their implementation. Secondary data was collected from books and the Internet.
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Stele, Kelsey A., BCIT School of Health Sciences, Environmental Health, and Helen Heacock. "Environmental sampling for legionella proliferation risk in three long-term care facilities in Vancouver, British Columbia." BCIT Environmental Public Health Journal, April 26, 2015. http://dx.doi.org/10.47339/ephj.2018.59.
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Background: Legionella is a pathogen that causes Legionnaires’ disease in high risk populations. The pathogen is known to exist in plumbing systems that do not have preventative factors in place to prevent its growth and proliferation. Legionella grows between 25˚C and 42˚C and is killed at 60˚C, yet long-term care facilities (LTCFs) reduce accessible hot water temperatures from 60˚C at the hot water tank to less than 49˚C at the taps in order to prevent scalding of their residents. Currently, prevention against scalding takes precedence as temperature at accessible taps is regulated within the Residential Care Regulation (RCR) of the Community Care and Assisted Living Act. It is thought that Legionella proliferation risk can be balanced with scalding in-part through the appropriate installation location of thermostatic mixing valves (TMVs). Methods: Three LTCFs in Vancouver, British Columbia were selected for environmental sampling for Legionella proliferation risk. At each LTCF the author recorded the type of hot water tank, temperature of water within the hot water tank, the presence of a TMV and temperature of pipes before and after the TMV. As well, the author recorded hot water temperatures after one minute and free available chlorine concentration ([FAC]) at numerous resident-accessible taps throughout each LTCF. Results: The hot water tank temperatures were set at 60.6˚C, 73.0˚C and 62.0˚C for LTCF #1, LTCF #2 and LTCF #3, respectively. All three LTCFs had installed a TMV within the boiler room immediately after the hot water tank. It was found that LTCF #1’s plumbing system water temperature was reduced from 60.6˚C (at the tank) to 48.9˚C after the TMV. LTCF #2’s plumbing system water temperature was reduced from 73.0˚C (at the tank) to 43.3˚C after the TMV. LTCF #3 was an older plumbing system that did not have thermometers within the boiler room to check the drop in temperature after the TMV. Water temperatures at taps were compared to a standard of 49°C and [FAC] levels at taps to a standard of 0.2 mg/L. The mean hot water temperature and mean [FAC] residual for all three LTCFs were 40.2˚C and 0.27 mg/L, respectively. For all three LTCFs, it was statistically significant that mean water temperatures were less than the comparison value of 49˚C (LTCF #1 p = 0.00000, LTCF #2 p = 0.00022, LTCF #3 p = 0.00110). It was also statistically significant that the mean [FAC] of all three LTCFs were greater than the comparison vale of 0.20 mg/L (LTCF #1 p = 0.00042, LTCF #2 p = 0.00000, LTCF #3 p = 0.00107). Conclusion: It was found that all three LTCFs had set preventive measures in place to protect their residents. Water was heated to at least 60˚C to prevent Legionella and lowered to less than 49˚C to prevent scalding. [FAC] residual was also adequate to prevent growth of Legionella. However, the location of the TMV in the boiler room was suspected to be a possible contributing factor to Legionella growth, especially if cold water temperatures were to reach 20˚C or above, as they could in warm summer months. Further research is needed to determine the significance of the TMV location and the presence of Legionella.