Tailrace surge shaft optimization procedure for minimum downsurge

2018 ◽  
Vol 45 (6) ◽  
pp. 446-457
Author(s):  
Satyajeet Sinha
Keyword(s):  
Optimization Procedure ◽  
Water Velocity ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Tailrace Tunnel ◽  
The Cross ◽  
The Cost ◽  
Low Pressures ◽  
The Relationship

Tailrace surge shafts are required in hydropower projects where the spent water is conveyed through a long tailrace tunnel under pressure to the recipient. Startup and shutdown of the turbine can cause sudden changes in water velocity and can develop dangerously high and low pressures. Surge shafts are provided in water conductor systems to significantly reduce these pressure surges. Based on numerous transient analyses carried out, it was observed that the cross-sectional area of the tailrace surge shaft can be optimized based on the relationship between the differences in the tailwater level and the minimum downsurge level at the tailrace surge shaft obtained with respect to the different lengths of the tailrace tunnel and different cross-sectional areas of the tailrace surge shaft. In this study, a procedure was proposed by which the tailrace surge shafts can be optimized and, hence, the cost of the hydropower projects with tailrace surge shafts can be minimized.

The relationship between jaw-opening force and the cross-sectional area of the suprahyoid muscles in healthy elderly

2017 ◽  
Vol 45 (3) ◽  
pp. 222-227 ◽  
Author(s):  
E. Kajisa ◽  
H. Tohara ◽  
A. Nakane ◽  
Y. Wakasugi ◽  
K. Hara ◽  
...  
Keyword(s):  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Suprahyoid Muscles ◽  
Healthy Elderly ◽  
Jaw Opening ◽  
The Cross ◽  
The Relationship

scholarly journals SIMULASI LUAS PENAMPANG STREET INLET JALAN YOS SUDARSO KOTA PALANGKA RAYA

2021 ◽  
Vol 10 (1) ◽  
pp. 40-48
Author(s):  
I Made Kamiana
Keyword(s):  
Water Depth ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
The Road ◽  
M 10 ◽  
Design Discharge ◽  
The Cross ◽  
On The Road ◽  
The Relationship

Abstract: The inaccurate of cross-sectional area of the street inlet can be one of the flooding causes on the road surface when the rainfall intensity is very high. This study aims to simulate the relationship between the cross-sectional area of the street inlet and the street inlet distance at Jalan Yos Sudarso, Palangka Raya City. The length of the reviewed road is 0.5 km. The simulation using an analytical approach. In the simulation, the street inlet distance variations are 5 m, 10 m, and 20 m; variations of the design discharge return period are 2 years, 5 years, and 10 years; variations of design water depth in the gutter are 1 cm, 1.5 cm, and 2 cm. The results show, the cross-sectional area of street inlet is getting bigger if the street inlet distance is getting bigger. At each street inlet distance, the cross-sectional area of street inlet is directly proportional to the design discharge and inversely proportional to the design water depth in the gutter. The cross-sectional area of street inlet at the street inlet distance of 5 m ranges from 62.72 to 284.42 m2, at the street inlet distance of 10 m ranges from 177.84 to 498.29 m2, and at the street inlet distance of 10 m ranges from 345.41 to 809.62 m2.Keywords : street inlet, cross-sectional area, street inlet distance, design discharge, gutterAbstrak: Tidak tepatnya luas penampang street inlet dapat menjadi salah satu penyebab genangan di permukaan jalan ketika hujan lebat. Penelitian ini bertujuan untuk mensimulasikan hubungan luas penampang street inlet dengan jarak street inlet. Jalan yang ditinjau adalah Jalan Yos Sudarso Kota Palangka Raya. Panjang jalan yang ditinjau 0,5 km. Simulasi dilakukan secara analitis. Dalam simulasi tersebut, variasi jarak street inlet yaitu 5 m, 10 m, dan 20 m; variasi periode ulang debit rencana yaitu 2 tahun, 5 tahun, dan 10 tahun; variasi kedalaman air rencana di saluran pembawa yaitu: 1 cm, 1,5 cm, dan 2 cm. Dari hasil simulasi diketahui luas penampang street inlet semakin besar apabila jarak street inlet semakin besar. Pada setiap jarak street inlet, luas penampang street inlet berbanding lurus dengan debit rencana dan berbanding terbalik dengan kedalaman air rencana di saluran pembawa. Luas penampang street inlet pada jarak street inlet 5 m berkisar antara 62,72-284,42 m2, pada jarak street inlet 10 m berkisar antara 177,84-498,29 m2, dan pada jarak street inlet 20 m berkisar antara 345,41-809,62 m2.Kata kunci : luas penampang street inlet, jarak steet inlet, debit rencana, saluran pembawa

scholarly journals Optimization of Thermal Backfill Configurations for Desired High-Voltage Power Cables Ampacity

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1452 ◽  
Author(s):  
Stanislaw Czapp ◽  
Filip Ratkowski
Keyword(s):  
High Voltage ◽  
Cross Sectional Area ◽  
Power Cable ◽  
Power Cables ◽  
Sectional Area ◽  
Cable System ◽  
Cross Sectional ◽  
The Core ◽  
The Cross ◽  
The Cost

The ampacity of high-voltage power cables depends, among others, on their core cross-sectional area as well as thermal resistivity of the thermal backfill surrounding the cables. The cross-sectional area of the power cables’ core is selected according to the expected power to be transferred via the cable system. Usually, the higher the power transfer required, the higher the cross-sectional area of the core. However, the cost of high-voltage power cables is relatively high and strictly depends on the dimensions of the core. Therefore, from the economic point of view, it is interesting to focus on the improvement of the thermal condition around the cables, by changing the dimension of the thermal backfill, instead of increasing the power cables’ core cross-sectional area. In practice, it is important to find the optimal dimensions of both cable core and thermal backfill to achieve the economically attractive solution of the power cable transfer system. This paper presents a mathematical approach to the power-cable system design, which enables selecting the cost-optimal cross-section of a power cable core depending on the dimensions of the thermal backfill. The proposal herein allows us to indicate the condition in which it is advantageous to increase the core cross-sectional area or to expand the dimension of the backfill. In this approach, the optimal backfill geometry can also be evaluated. The investment costs of the 110 kV power cable system with the core cross-sectional areas consecutively equal to 630, 800 and 1000 mm2 have been compared.

scholarly journals influence of the palate shape on articulatory token-to-token variability

2005 ◽  
Vol 42 ◽  
pp. 43-67
Author(s):  
Jana Brunner ◽  
Susanne Fuchs ◽  
Pascal Perrier
Keyword(s):  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Acoustic Variability ◽  
The Cross ◽  
Two Parameters ◽  
Acoustic Output ◽  
The Relationship ◽  
Modelling Study ◽  
Motor Constraints

Articulatory token-to-token variability not only depends on linguistic aspects like the phoneme inventory of a given language but also on speaker specific morphological and motor constraints. As has been noted previously (Perkell (1997), Mooshammer et al. (2004)), speakers with coronally high "domeshaped" palates exhibit more articulatory variability than speakers with coronally low "flat" palates. One explanation for that is based on perception oriented control by the speaker. The influence of articulatory variation on the cross sectional area and consequently on the acoustics should be greater for flat palates than for domeshaped ones. This should force speakers with flat palates to place their tongue very precisely whereas speakers with domeshaped palates might tolerate a greater variability. A second explanation could be a greater amount of lateral linguo-palatal contact for flat palates holding the tongue in position. In this study both hypotheses were tested. In order to investigate the influence of the palate shape on the variability of the acoustic output a modelling study was carried out. Parallely, an EPG experiment was conducted in order to investigate the relationship between palate shape, articulatory variability and linguo-palatal contact. Results from the modelling study suggest that the acoustic variability resulting from a certain amount of articulatory variability is higher for flat palates than for domeshaped ones. Results from the EPG experiment with 20 speakers show that (1.) speakers with a flat palate exhibit a very low articulatory variability whereas speakers with a domeshaped palate vary, (2.) there is less articulatory variability if there is lots of linguo-palatal contact and (3.) there is no relationship between the amount of lateral linguo-palatal contact and palate shape. The results suggest that there is a relationship between token-to-token variability and palate shape, however, it is not that the two parameters correlate, but that speakers with a flat palate always have a low variability because of constraints of the variability range of the acoustic output whereas speakers with a domeshaped palate may choose the degree of variability. Since linguo-palatal contact and variability correlate it is assumed that linguo-palatal contact is a means for reducing the articulatory variability.  

scholarly journals PENGARUH PENINGKATAN SUHU DAN BESARAN ARUS TERHADAP TAHANAN PENGHANTAR KABEL LISTRIK TEGANGAN RENDAH JENIS NYM

2020 ◽  
Vol 4 (1) ◽  
pp. 35-40
Author(s):  
Kiki Rosiana Dewi ◽  
Suyitno ◽  
Nur Hanifah Yuninda
Keyword(s):  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Cross Section Area ◽  
Section Area ◽  
Chamber Temperature ◽  
Conductor Temperature ◽  
The Cross ◽  
Increasing Temperature ◽  
The Relationship

The purpose of this research is to know about influence of temperature increasing and current rate on the conductor resistance, the conductor temperature and the conductor power losses of the conductors of the cable brand A and brand B due to the effect of increasing temperature and current magnitude. Increasing the temperature and currents rate have a bigger influence on the increase of temperature conductor, the resistance conductor and conductor losses the electric cable brand B compared to the brand A. The electricity cable  brand B is a conductor that does not have standardization suitable for electrical installation. The conductor of brand A electrical cable is a cable conductor that has standardization and is suitable for use. At chamber temperature of 25 ℃ the test current 5 A the value of conductor resistance 2 x 1.5 mm2 of brand A increases by 11,90 mΩ while brand B increases by 23.32 mΩ. The maximum conductor resistance according to standardization is 12,10 mΩ for a cross section area of ​​1.5 mm2. Based on the test results, each increase in temperature and the currents rate have an influence for increasing value of the conductor temperature, the conductor resistance and conductor losses are bigger. The relationship between the conductor resistance and the cross-sectional area is that the smaller the cross-sectional area, the bigger the conductor resistance. ABSTRAK Tujuan dari penelitian ini adalah untuk mengetahui pengaruh peningkatan suhu dan besaran arus terhadap nilai tahanan penghantar, suhu penghantar dan rugi daya penghantar pada penghantar kabel listrik merk A dan merk B. Peningkatan suhu dan besaran arus mempunyai pengaruh yang lebih besar terhadap kenaikan suhu penghantar, tahanan penghantar dan rugi daya penghantar kabel listrik merk B dibandingkan dengan merk A. Penghantar kabel merk B merupakan penghantar yang tidak memiliki standarisasi layak pakai dalam instalasi listrik. Penghantar kabel listrik merk A merupakan penghantar kabel yang telah memiliki standarisasi dan layak pakai. Pada suhu chamber 25 arus pengujian 5 A nilai tahanan penghantar 2 x 1,5 mm2 merk A meningkat sebesar 11,90 mΩ sedangkan merk B meningkat sebesar 23,32 mΩ. Nilai tahanan penghantar maksimal sesuai dengan standarisasi adalah sebesar 12,10 mΩ untuk luas penampang 1,5 mm2. Berdasarkan hasil pengujian, setiap peningkatan suhu dan besaran arus nilai memiliki pengaruh terhadap kenaikan nilai suhu penghantar, tahanan penghantar dan rugi daya penghantar semakin besar. Hubungan antara tahanan penghantar dengan luas penampang yaitu dengan semakin kecil luas penampang maka nilai tahanan penghantar semakin besar.

scholarly journals Atrophy patterns in isolated subscapularis lesions

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Gernot Seppel ◽  
Andreas Voss ◽  
Daniel J. H. Henderson ◽  
Simone Waldt ◽  
Bernhard Haller ◽  
...  
Keyword(s):  
Muscle Atrophy ◽  
Area Ratio ◽  
Cross Sectional Area ◽  
Control Group ◽  
Sectional Area ◽  
Cross Sectional ◽  
Subscapularis Muscle ◽  
Mri Scans ◽  
The Mean ◽  
The Cross

Abstract Background While supraspinatus atrophy can be described according to the system of Zanetti or Thomazeau there is still a lack of characterization of isolated subscapularis muscle atrophy. The aim of this study was to describe patterns of muscle atrophy following repair of isolated subscapularis (SSC) tendon. Methods Forty-nine control shoulder MRI scans, without rotator cuff pathology, atrophy or fatty infiltration, were prospectively evaluated and subscapularis diameters as well as cross sectional areas (complete and upper half) were assessed in a standardized oblique sagittal plane. Calculation of the ratio between the upper half of the cross sectional area (CSA) and the total CSA was performed. Eleven MRI scans of patients with subscapularis atrophy following isolated subscapularis tendon tears were analysed and cross sectional area ratio (upper half /total) determined. To guarantee reliable measurement of the CSA and its ratio, bony landmarks were also defined. All parameters were statistically compared for inter-rater reliability, reproducibility and capacity to quantify subscapularis atrophy. Results The mean age in the control group was 49.7 years (± 15.0). The mean cross sectional area (CSA) was 2367.0 mm2 (± 741.4) for the complete subscapularis muscle and 1048.2 mm2 (± 313.3) for the upper half, giving a mean ratio of 0.446 (± 0.046). In the subscapularis repair group the mean age was 56.7 years (± 9.3). With a mean cross sectional area of 1554.7 mm2 (± 419.9) for the complete and of 422.9 mm2 (± 173.6) for the upper half of the subscapularis muscle, giving a mean CSA ratio of 0.269 (± 0.065) which was seen to be significantly lower than that of the control group (p < 0.05). Conclusion Analysis of typical atrophy patterns of the subscapularis muscle demonstrates that the CSA ratio represents a reliable and reproducible assessment tool in quantifying subscapularis atrophy. We propose the classification of subscapularis atrophy as Stage I (mild atrophy) in case of reduction of the cross sectional area ratio < 0.4, Stage II (moderate atrophy) in case of < 0.35 and Stage III (severe atrophy) if < 0.3.

The area of eye muscle of beef cattle carcasses

1963 ◽  
Vol 3 (10) ◽  
pp. 249
Author(s):  
RM Seebeck
Keyword(s):  
Beef Cattle ◽  
Cross Sectional Area ◽  
Carcass Weight ◽  
Sectional Area ◽  
Muscle Area ◽  
Cross Sectional ◽  
Eye Muscle ◽  
Angus Cattle ◽  
The Cross

Variations in the cross-sectional area of eye muscle of carcasses cut between the tenth and eleventh ribs were investigated, using 105 Hereford and 51 Angus steers aged 20 months. These cattle consisted of three groups, born in successive years. At constant carcass weight, statistically significant differences in eye muscle area were found between breeds and between years. Breed and year differences were also found in eye muscle area with width and depth of eye muscle constant, so that there are limitations to the estimation of eye muscle area from width and depth measurements. A nomograph is given for estimating eye muscle area from width and depth for Hereford and Angus cattle, when all animals are reared in the same year and environment. The use of eye muscle area as an indicator of weight of carcass muscle is discussed.

Comparison of the Cross Sectional Area, the Loss in Volume and the Mechanical Properties of LAE442 and MgCa0.8 as Resorbable Magnesium Alloy Implants after 12 Months Implantation Duration

2010 ◽  
Vol 638-642 ◽  
pp. 675-680 ◽  
Author(s):  
Martina Thomann ◽  
Nina von der Höh ◽  
Dirk Bormann ◽  
Dina Rittershaus ◽  
C. Krause ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Cross Sections ◽  
Degradation Process ◽  
Cross Sectional Area ◽  
Bending Test ◽  
Sectional Area ◽  
Cross Sectional ◽  
Initial Strength ◽  
Three Point Bending ◽  
The Cross

Current research focuses on magnesium based alloys in the course of searching a resorbable osteosynthetic material which provides sufficient mechanical properties besides a good biocompatibility. Previous studies reported on a favorable biocompatibility of the alloys LAE442 and MgCa0.8. The present study compared the degradation process of cylindrical LAE442 and MgCa0.8 implants after 12 months implantation duration. Therefore, 10 extruded implants (2.5 x 25 mm, cross sectional area 4.9 mm²) of both alloys were implanted into the medullary cavity of both tibiae of rabbits for 12 months. After euthanization, the right bone-implant-compound was scanned in a µ-computed tomograph (µCT80, ScancoMedical) and nine uniformly distributed cross-sections of each implant were used to determine the residual implants´ cross sectional area (Software AxioVisionRelease 4.5, Zeiss). Left implants were taken out of the bone carefully. After weighing, a three-point bending test was carried out. LAE442 implants degraded obviously slower and more homogeneously than MgCa0.8. The mean residual cross sectional area of LAE442 implants was 4.7 ± 0.07 mm². MgCa0.8 showed an area of only 2.18 ± 1.03 mm². In contrast, the loss in volume of LAE442 pins was more obvious. They lost 64 % of their initial weight. The volume of MgCa0.8 reduced clearly to 54.4 % which corresponds to the cross sectional area results. Three point bending tests revealed that LAE442 showed a loss in strength of 71.2 % while MgCa0.8 lost 85.6 % of its initial strength. All results indicated that LAE442 implants degraded slowly, probably due to the formation of a very obvious degradation layer. Degradation of MgCa0.8 implants was far advanced.

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