scholarly journals Coastal and deep deformations of the riverbed in the area of a damless water intake

2021 ◽  
Vol 263 ◽  
pp. 02031
Author(s):  
Dilshod Bazarov ◽  
Irina Markova ◽  
Sanatjon Khidirov ◽  
Oybek Vokhidov ◽  
Farokhiddin Uljaev ◽  
...  
Keyword(s):  
Water Intake ◽  
Water Flow Rate ◽  
High Mobility ◽  
Field Studies ◽  
The State ◽  
Maximum Speed ◽  
Flow Rates ◽  
Head Section ◽  
Hydraulic Regime ◽  
Short Time

The paper analyzes the dynamics of planned and deep deformations on the section of the Amudarya River in the area of the damless water intake in the main structure of the Karshi Main Canal-KMC. The results of field studies of the state of the canal situation of the Amudarya River at the site of a damless water intake are studied. The course of riverbed processes in the riverbed is studied. Recommendations for improving water intake conditions have been developed. According to the results of the field survey and the study of the head section of the supply canal, the state of the Amudarya riverbed in the water intake zone was assessed. The results of surveys of the hydraulic and pumping modes of sediments of the Amudarya River in the area of the damless water intake are analyzed and summarized. The results of field studies of the canal situation of the Amudarya River in the water intake area in the Amudarya River KMC in the area of the Karshi head water intake are studied. The riverbed situation is not characterized by constant hydraulic characteristics over time for the same water flow rate, i.e. with the same water horizon marks, the flow rates may differ from each other by about half, and with the same flow rates, the horizon marks may vary up to ± 0.6 m. This is explained by the extreme instability and high mobility of the canal, and large deformations of the canal occur in a short time. The hydraulic regime of the river is characterized by a significant redistribution of speeds, depth and width of the flow. The range of their changes is within: Maximum speed >Vmax =2…5 m/s; average speed Vav = 0.5…2.5 m/s; depth H max = 4…14 m, Hav = 1…5 m; width B = 300…2000 m; slope i = 0.00016…0.0003. It is established that the characteristic feature of the river is that at a constant flow can have different average velocities depth and width, for example, when Qw = 1000 m3/s, respectively, v = 0.6…1.7m/s, B = 180…1030m, Hav = 1.1…4.3m.

scholarly journals Hydraulic studies of the throughput of the water intake structure of the Tuyamuyun hydroelectric complex

2021 ◽  
Vol 264 ◽  
pp. 03059
Author(s):  
Ulmas Khusankhodjaev ◽  
Odil Kadyrov
Keyword(s):  
Water Intake ◽  
Flow Rate ◽  
Mutual Influence ◽  
Water Flow Rate ◽  
Experimental Studies ◽  
Total Consumption ◽  
Hydraulic Regime ◽  
Upper Pool ◽  
The Right ◽  
Intake Structure

The article presents the results of experimental studies to determine the throughput of the right-bank water intake structure and bottom galleries, the hydraulic regime in the galleries, and the movement of bottom sediments in them. Based on the results of the studies, a series of curves were obtained for the dependence of the discharge on the water horizon in the upper pool and the value of the opening of the gate of the intake structure. Checking the work of the galleries together with the working water intake holes showed that there is no mutual influence of them on each other. The total consumption of water passed through the water intake and galleries is practically equal to the sum of the consumption of water passed through these structures separately. It was found that the main amount of sediment accumulated in the headwater will fall into the left gallery, while slightly less (about one third) will fall into the right span, and only a small remainder leaves through the weir, while the water flow rate was distributed as follows: Qgal = 1.65Qwater.

scholarly journals HORMONE STUDIES WITH THE ULTRACENTRIFUGE

1938 ◽  
Vol 68 (1) ◽  
pp. 1-16 ◽  
Author(s):  
James A. Chiles ◽  
Aura E. Severinghaus
Keyword(s):  
Compressed Air ◽  
Maximum Speed ◽  
Driving Mechanism ◽  
Air Bearing ◽  
Centrifugal Field ◽  
Air Turbine ◽  
Full Speed ◽  
Short Time ◽  
Centrifuge Rotor

1. An ultracentrifuge is described in which the rotor is driven by a compressed air turbine, and is spun in an evacuated chamber to minimize friction and heating. The rotating parts are supported by a cushion of air in an air bearing. 2. The centrifuge rotor holds 10 test tubes inclined at 45° to the axis, and has a capacity of 55 cc. It is operated at a maximum speed of 51,000 R.P.M., which develops at the top of the fluid column in the test tubes a centrifugal field of over 100,000 times gravity, and at the bottom of the fluid column a field of over 200,000 times gravity. 3. By means of a reverse turbine, the rotor can be brought to a stop from full speed in a relatively short time. 4. A precession damping device is described, which effectively damps the precession and wobbling of the rotor that usually occurs at certain speeds in machines of this type. 5. A relatively long section of shaft is used between the centrifuge rotor and lower bearings. This prevents vibrations from being appreciably transmitted through the shaft to the lower bearings and driving mechanism, and results in a negligible wear on the bearings. 6. The driving mechanism is designed so that the positions of its parts are adjustable, and so that the driving mechanism may be dismantled without disturbing these adjustments.

Biathlon Performance: Heart Rate, Hit Rate, Speed and Physiological Variables

2021 ◽  
Vol 15 (10) ◽  
pp. 3245-3249
Author(s):  
Gökhan Atasever ◽  
Fatih Kiyici ◽  
Deniz Bedir ◽  
Fatih Ağduman
Keyword(s):  
Heart Rate ◽  
Lean Body Mass ◽  
Body Mass ◽  
Body Fat ◽  
Maximum Speed ◽  
Fat Percentage ◽  
Physiological Variables ◽  
Cross Country Skiing ◽  
Cross Country ◽  
Short Time

Aim: Biathlon is a sport that combines cross-country skiing and rifle shooting. The athlete is fast in the cross-country skiing section, in the gun shooting section, the heart rate should be low. This study aims to determine the hitting rate of the shots made with different training loads on low altitude in elite biathletes in terms of maximum speed and physiological variables. Methods: To evaluate shooting performances first with the resting pulse and then after 2.5 km skiing respectively with 50%, 70% and 100% pulse rate which is separately calculated for each athlete according to karvonen formula. Results: Our findings show that while there was negative relation between maximum speed and body fat there was a positive relation with lean body mass. It has been determined that low body fat percentage and high lean body mass are effective at the athletes’ maximum speed and the pulse level with the highest target shooting accuracy rate was at rest and 70% in the second level. Conclusion: Since the pulse of the athlete who comes to the shooting area cannot be reduced to a resting level in a short time, focusing the 70% pulse zone may be beneficial in terms of shooting accuracy and acceleration after the shot. The lowest results in target shooting accuracy were seen at 50% and 100% loads. Keywords: Athletes, performance, heart, rate, lean body mass.

BIODIVERSITI DAN PEMULIHARAAN TERUMBU KARANG DI TIGA BUAH PULAU, MELAKA (Biodiversity and Conservation of Coral Reefs in Three Islands in Malacca)

2021 ◽  
Vol 22 (1) ◽  
pp. 180-197
Author(s):  
SYAIMAK ISMAIL ◽  
MOHAMAD SAUPI BIN ISMAIL ◽  
MUHAMMAD SAIFUL ISLAM ISMAIL ◽  
AEMY AZIZ
Keyword(s):  
Coral Reefs ◽  
Biodiversity Conservation ◽  
Soft Coral ◽  
Good Condition ◽  
Scuba Diving ◽  
Field Studies ◽  
The State ◽  
Hard Coral ◽  
Wide Range ◽  
State Museum

In the state of Melaka, there are eighteen islands recorded by the Melaka State Museum Corporation (PERZIM). Part of this island serves as a tourist island, and developed islands are also uninhabited islands. However, three islands are recorded to have amazing coral reefs that are still in good condition. The Penang Batu Maung Fisheries Research Institute (AkuaTAR) has conducted a study on the biodiversity of coral reefs around the waters of Pulau Dodol, Pulau Serimbun, and Pulau Undan. AkuaTAR researchers are using scuba diving methods, and at the same time, they did conservation on coral reefs that have been identified in the waters of the Straits of Melaka. The objective of this study is to record the types of community forms such as living corals and identify the species of coral reefs found in three islands in the state of Melaka in Pulau Undan, Pulau Dodol, and Pulau Serimbun. The study also implemented method observation by conducting field studies on the islands involved by doing scuba diving. Results and discussion of the search, these three islands are located in very clean, uninhabited waters. They have a wide range of coral biodiversity using soft coral reefs and hard coral reefs. The study also found that the three islands in the state have the largest coral reefs in the waters of the Straits of Melaka. Keywords: Biodiversity; Conservation; Coral; Three island; Melaka

Edukacja cyfrowa w zdalnym nauczaniu

2021 ◽  
Vol 1 (23) ◽  
pp. 49-58
Author(s):  
Bożena Majewicz
Keyword(s):  
Distance Education ◽  
Distance Learning ◽  
Online Education ◽  
The State ◽  
Educational Activity ◽  
Special Role ◽  
Remote Education ◽  
School Closures ◽  
Short Time

The state of education in Poland and its functioning was exposed by the coronavirus pandemic which contributed to school closures and enforced a transition to distance learning. There was a need to look for alternative ways of distance education in which teachers played a special role. Some of them had to learn new skills related to distance education at all levels of education in a short time. In the period when schools are closed or their functioning is limited, the competences they possess play an important role in the educational activity of teachers, among which IT and media competences become particularly important. The considerations presented in the article relate to online education, with particular attention to its necessary aspects occurring both on the side of school and students’ homes. A review of studies on remote education during the pandemic has been made.

Bubble dynamics and oxygen transfer in a hypolimnetic aerator

1998 ◽  
Vol 37 (2) ◽  
pp. 293-300 ◽  
Author(s):  
Vickie L. Burris ◽  
John C. Little
Keyword(s):  
Gas Phase ◽  
Bubble Size ◽  
Oxygen Transfer ◽  
Bubble Dynamics ◽  
Water Flow Rate ◽  
Flow Rates ◽  
Wide Range ◽  
The City ◽  
Close Fit ◽  
Water Supply Reservoirs

A hypolimnetic aerator operating in one of the City of Norfolk's water supply reservoirs was tested. Dissolved oxygen (DO) profiles, water flow rate, and gas-phase holdup were measured over a wide range of applied air flow rates. A model that was developed to predict oxygen transfer in a Speece Cone was modified to conform to the conditions of the hypolimnetic aerator. By varying a single parameter (the initial bubble size) the model was found to provide a close fit to the experimental DO profiles as well as the observed gas-phase holdup. The model was used to show that a doubling in oxygen transfer may be achieved if initial bubble size is reduced from 5 mm to 2.5 mm. Knowing the initial bubble size, it should be possible to predict water velocity by incorporating the effect of momentum. Further work is now underway to test this approach and to examine the possibility of extending this generalized model to cover the range of hypolimnetic aeration and oxygenation devices.

scholarly journals LAYOUT AND DESIGN SOLUTIONS OF FILTERING WATER INTAKES FROM SHALLOW WATERCOURSES FOR DRIP IRRIGATION SYSTEMS

2021 ◽  
Author(s):  
A. S. Shtanko ◽  
◽  
V. N. Shkura ◽  
Keyword(s):  
Water Intake ◽  
Drip Irrigation ◽  
Agricultural Development ◽  
Drainage Water ◽  
Low Flow ◽  
Mountain Streams ◽  
Irrigation Systems ◽  
Flow Rates ◽  
Hydrographic Features ◽  
Sand And Gravel

Purpose: development of layout and design schemes for low-flow water intakes, arranged on shallow river and stream watercourses for supplying water to drip irrigation systems. Agricultural development of terraces and floodplains of small foothill and mountain streams actualizes the development of facilities for water intake from them for the purpose of irrigating land. Morphological and hydrographic features, including shallow low-water depths, high flow rates, flow rates variability, saturation with sediments, the presence of underflow and overflow runoff, etc., make water intake from such watercourses difficult and specific. These circumstances predetermine the relevance of water intake structures development corresponding to the specified conditions. Materials and Methods. When developing the layout and design schemes of low-flow water intakes from shallow watercourses, the technologies of exploratory design of engineering systems and structures were used. Results. With regard to the morphometric, hydrological and other conditions of shallow foothill and mountain streams, a water intake with a bottom water intake was adopted for development. The water intake part of headworks is designed in the form of a toe drain, which has under-flow and overflow intake parts that allow water intake from the channel and off-channel water streams. The toe is made of two or three layers of sand and gravel material. Drainage pipes or pipe filters are used as a drainage element. Depending on the conditions of the watercourse, water intakes with transverse, longitudinal and pocket-coastal placement of water intakes are proposed. Conclusion. The layout and design schemes of filtering water intakes from shallow watercourses based on the use of overflow, underflow and combined structures of multilayer drainage water intakes with stream (transverse and longitudinal) and off-channel (pocket-coastal) placement have been proposed and developed.

scholarly journals Rancang Bangun Mesin Pengecat Otomatis Berbasis PLC CP1E NA20DR A

2019 ◽  
Vol 1 (3) ◽  
pp. 118
Author(s):  
Fahmi Abdul Aziz ◽  
Riky Dwi Puriyanto
Keyword(s):  
Flat Surface ◽  
State Diagram ◽  
Dc Motor ◽  
The State ◽  
Ladder Diagram ◽  
Maximum Speed ◽  
Well Testing ◽  
Diagram Method ◽  
Limit Switch

Dalam hal mengecat tidak semua orang dapat melakukan pengecatan dengan sempurna, banyak hasil cat yang tidak merata atau lapisan yang terlalu tebal dan terlalu tipis. Tujuan penelitian ini adalah membuat sebuah alat yang membantu manusia untuk mengecat objek di permukaan datar secara otomatis. Komponen yang digunakan dalam penelitian ini yaitu motor DC PG28, sensor encoder, sensor limit switch dan PLC Omron CP1E-NA20DR-A. Alat ini bergerak berdasarkan sumbu x dan y yaitu bergerak ke atas-bawah dan ke kanan-kiri, kemudian untuk pengecatanya menggunakan roll cat. Setiap pergerakan alat di program menggunakan ladder diagram di software CX-Programmer. Untuk memonitor pergerakan mesin peneliti membuat HMI dari software CX-Designer. Pada pembuatan program ladder diagram peneliti menggunakan metode state diagram karena metode ini dapat menyusun program ladder dengan baik. Pengujian pembacaan RPM motor peneliti membandingkan data dari PLC dengan tachometer dan didapat error sebesar 0,52%. Pergerakan alat pada sumbu x didapat dengan mengendalikan pulsa putaran per rotasi yang terbaca 1380 pulsa per 10 cm oleh sensor encoder. Jarak 10 cm mengacu pada lebar dari roll cat yang dipakai. Kemudian dengan tegangan luar sebesar 12V didapat kecepatan maksimun pada motor DCPG28 sebesar 379 RPM.In the case of painting not everyone can paint perfectly, many paints are not evenly distributed or layers that are too thick and too thin. The purpose of this research is to create a tool that helps humans to paint objects on a flat surface automatically. The components used in this study are the PG28 DC motor, encoder sensor, limit switch sensor and PLC Omron CP1E-NA20DR-A. This tool moves based on the x and y axis that is moving up-down and right-left, then for painting using a paint roll. Every movement of tools in the program uses ladder diagrams in the CX-Programmer software. To monitor the movement of the engine the researcher made an HMI from the CX-Designer software. In making ladder diagram programs researchers use the state diagram method because this method can arrange ladder programs well. Testing the RPM reads the motorbike comparing the data from the PLC with the tachometer and obtained an error of 0.52%. The movement of the tool on the x-axis is obtained by controlling the rotational pulses per rotation which reads 1380 pulses per 10 cm by the encoder sensor. A distance of 10 cm refers to the width of the paint roll used. Then with an outside voltage of 12V, the maximum speed of the DCPG28 motor is 379 RPM.

A new correlation-based approach for ensemble selection in random forests

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Mostafa El Habib Daho ◽  
Nesma Settouti ◽  
Mohammed El Amine Bechar ◽  
Amina Boublenza ◽  
Mohammed Amine Chikh
Keyword(s):  
State Of The Art ◽  
Ensemble Methods ◽  
The State ◽  
Ensemble Classifiers ◽  
Content Type ◽  
Pruning Method ◽  
Ensemble Selection ◽  
Small Ensemble ◽  
Short Time ◽  
Pruning Techniques

PurposeEnsemble methods have been widely used in the field of pattern recognition due to the difficulty of finding a single classifier that performs well on a wide variety of problems. Despite the effectiveness of these techniques, studies have shown that ensemble methods generate a large number of hypotheses and that contain redundant classifiers in most cases. Several works proposed in the state of the art attempt to reduce all hypotheses without affecting performance.Design/methodology/approachIn this work, the authors are proposing a pruning method that takes into consideration the correlation between classifiers/classes and each classifier with the rest of the set. The authors have used the random forest algorithm as trees-based ensemble classifiers and the pruning was made by a technique inspired by the CFS (correlation feature selection) algorithm.FindingsThe proposed method CES (correlation-based Ensemble Selection) was evaluated on ten datasets from the UCI machine learning repository, and the performances were compared to six ensemble pruning techniques. The results showed that our proposed pruning method selects a small ensemble in a smaller amount of time while improving classification rates compared to the state-of-the-art methods.Originality/valueCES is a new ordering-based method that uses the CFS algorithm. CES selects, in a short time, a small sub-ensemble that outperforms results obtained from the whole forest and the other state-of-the-art techniques used in this study.

Validity and Reliability of Socio-Cognitive Determinants of Water Intake Questionnaire in Kidney Stones Patients

2020 ◽  
Author(s):  
Mehdi Mirzaei-Alavijeh ◽  
Farzad Jalilian ◽  
Halimeh Fatahi ◽  
Laleh Solaimanizadeh ◽  
Abdollah Saadatfar ◽  
...  
Keyword(s):  
Internal Consistency ◽  
Water Intake ◽  
Kidney Stones ◽  
Psychometric Evaluation ◽  
Field Studies ◽  
Validity And Reliability ◽  
Intra Class Correlation ◽  
Theoretical Assumptions ◽  
Cognitive Determinants ◽  
Intra Class Correlation Coefficient

Abstract Background Developing a valid and reliable questionnaire is an important step in field studies. This study aimed to evaluate the psychometric propertiesof the socio-cognitive determinants of water intake questionnaire behaviors among patients with kidney stones in the west of Iran.Methods Construct items were elicited from interviews with kidney stones patients, experts and socio-cognitive items pool-related similar questionnaires. Internal consistency, face, content, and construct validity were evaluated. Data were analyzed by SPSS (ver. 20.0).Results Based on Eigenvalues of ≥ 1.00 and factor loadings of ≥ 0.40, five determinants were extracted. The calculated Kaiser–Meyer–Olkin (KMO) value was 0.697. The socio-cognitive determinants of water intake questionnaires were found to have acceptable internal consistency (Cronbach alpha of determinants between 0.65-0.85) and the theoretical assumptions for face, content, and construct validities were confirmed. The Intra-class Correlation Coefficient (ICC) of socio-cognitive determinants was high (ICC between 0.810 - 0.911). Overall, the five studied socio-cognitive determinants explained 73.83% of the variance in the proposed model.Conclusions The socio-cognitive determinants of water intake questionnaire were revealed to have an acceptable psychometric evaluation. The questionnaire could be used to predict or explain water intake behavior in order to develop programs to increase water intake behavior among kidney stones patients.

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