scholarly journals Comparison of the fall rate and structure of recent T-7 XBT manufactured by Sippican and TSK

2010 ◽  
Vol 7 (5) ◽  
pp. 1811-1847 ◽  
Author(s):  
S. Kizu ◽  
C. Sukigara ◽  
K. Hanawa
Keyword(s):  
Quadratic Form ◽  
Water Entry ◽  
Rate Coefficients ◽  
Fall Rate ◽  
Current Standard ◽  
Expendable Bathythermograph ◽  
Structural Differences ◽  
Fall Rates ◽  
The Difference ◽  
Temperature Depth

Abstract. The fall rate of recent T-7 expendable bathythermograph (XBT) is evaluated based on a series of concurrent measurement with a calibrated Conductivity Temperature Depth profiler (CTD) in the sea east of Japan. An emphasis is placed on comparing the fall rates of T-7 produced by the two present manufacturers, the Lockheed Martin Sippican Inc., and the Tsurumi Seiki Co. Ltd., which have been believed to be identical but had never been compared directly. It is found that the two manufacturers' T-7 fall at rates different by about 3.5%. The Sippican T-7 falls slower than the current standard equation by Hanawa et al. (1995) gives by about 2.1%, and the TSK T-7 falls faster than it tells by about 1.4%. The fall-rate coefficients estimated based on the present sea test by applying the equation of traditional quadratic form, d(t)=at−bt2 where d is depth in meters and t is the time elapsed, since the water entry of the probe, in seconds, are a=6.553 and b=0.00221 for the LMS T-7, and a=6.803 and b=0.00242 for the TSK T-7. By detail examination of the probes, it is revealed that the two companies' T-7 have different total weight and many structural differences. Because the difference in the fall rate is about twice larger than the difference in weight (about 2%), it is inferred that those structural differences give sizable impact to the difference in their fall rates. Our results clearly show that the recent T-7 of the two companies needs to be discriminated.

scholarly journals Comparison of the fall rate and structure of recent T-7 XBT manufactured by Sippican and TSK

Ocean Science ◽  
2011 ◽  
Vol 7 (2) ◽  
pp. 231-244 ◽  
Author(s):  
S. Kizu ◽  
C. Sukigara ◽  
K. Hanawa
Keyword(s):  
Quadratic Form ◽  
Rate Equation ◽  
Total Weight ◽  
Rate Coefficients ◽  
Fall Rate ◽  
Expendable Bathythermograph ◽  
Structural Differences ◽  
Fall Rates ◽  
The Difference ◽  
Temperature Depth

Abstract. The fall rate of recent T-7 expendable bathythermograph (XBT; 760 m) is evaluated based on a series of concurrent measurement with a calibrated Conductivity Temperature Depth profiler (CTD) in the sea east of Japan. An emphasis is placed on comparing the fall rates of T-7 produced by the two present manufacturers, the Lockheed Martin Sippican Inc., and the Tsurumi Seiki Co. Ltd., which have been believed to be identical but had never been compared directly. It is found that the two manufacturers' T-7 fall at rates different by about 3.5%. The Sippican T-7 falls slower than given by the fall-rate equation (FRE) of Hanawa et al. (1995) by about 2.1%, and the TSK T-7 falls faster by about 1.4%. The fall-rate coefficients estimated based on the sea test by applying the equation of traditional quadratic form, d(t)=at−bt2 where d is depth in meters and t is the time elapsed, in seconds, are a=6.553 (m s−1) and b=0.00221 (m s−2) for the LMS T-7, and a=6.803 (m s−1) and b=0.00242 (m s−2) for the TSK T-7. By detail examination of the probes, we found that the two companies' T-7 have different total weight and many structural differences. Because the difference in the fall rate is about twice larger than the difference in weight (about 2%), it is inferred that the structural differences give sizable impact to the difference in their fall rates. Our results clearly show that the recent T-7 of the two companies needs to be discriminated.

scholarly journals Biases in Expendable Bathythermograph Data: A New View Based on Historical Side-by-Side Comparisons

2013 ◽  
Vol 30 (6) ◽  
pp. 1195-1225 ◽  
Author(s):  
Rebecca Cowley ◽  
Susan Wijffels ◽  
Lijing Cheng ◽  
Tim Boyer ◽  
Shoichi Kizu
Keyword(s):  
Time History ◽  
Fall Rate ◽  
Ocean Temperature ◽  
Temperature Bias ◽  
Deep Blue ◽  
Bias Model ◽  
Fitting Method ◽  
Expendable Bathythermograph ◽  
History Of ◽  
Temperature Depth

Abstract Because they make up 56% of ocean temperature profile data between 1967 and 2001, quantifying the biases in expendable bathythermograph (XBT) data is fundamental to understanding the evolution of the planetary energy and sea level budgets over recent decades. The nature and time history of these biases remain in dispute and dominate differences in analyses of the history of ocean warming. A database of over 4100 side-by-side deployments of XBTs and conductivity–temperature–depth (CTD) data has been assembled, and this unique resource is used to characterize and separate out the pure temperature bias from depth error in a way that was not previously possible. Two independent methods of bias extraction confirm that the results are robust to bias model and fitting method. It was found that there is a pure temperature bias in Sippican probes of ~0.05°C, independent of depth. The temperature bias has a time dependency, being larger (~0.1°C) in the earlier analog acquisition era and being likely due to changes in recorder type. Large depth errors are found in the 1970s–80s in shallower-measuring Sippican T4/T6 probe types, but the deeper-measuring Sippican T7/Deep Blue (DB) types have no error during this time. The Sippican T7/DB fall rate slows from ~1990 onward. It is found that year-to-year variations in fall rate have a bigger effect on corrections to the global XBT database than do any small effects of ocean temperature on fall rate. This study has large implications for the future development of better schemes to correct the global historical XBT archive.

The fractional parts of an additive form

1972 ◽  
Vol 72 (2) ◽  
pp. 209-212 ◽  
Author(s):  
R. J. Cook
Keyword(s):  
Quadratic Form ◽  
Analogous Result ◽  
The Difference ◽  
Image Position ◽  
Forms Of Higher Degree ◽  
Additive Form ◽  
Real Quadratic

Heilbronn (6) proved that for every ε ≥ 0 and N ≥ 1 and every real θ there is an integer x such that,where C(ε) depends only on ε and ∥α∥ is the difference between α and the nearest integer, taken positively. Danicic(1) obtained an analogous result for the fractional parts of nkθ, the proof of this is more readily accessible in Davenport(4). Danicic(2) also obtained an estimate for the fractional parts of a real quadratic form in n variables, and in order to extend this result to forms of higher degree it is desirable to first obtain results for additive forms.

scholarly journals The role of vibrationally excited oxygen and nitrogen in the ionosphere during the undisturbed and geomagnetic storm period of 6-12 April 1990

1998 ◽  
Vol 16 (5) ◽  
pp. 589-601 ◽  
Author(s):  
A. V. Pavlov
Keyword(s):  
Loss Rate ◽  
Boltzmann Distribution ◽  
Rate Coefficients ◽  
Ion Chemistry ◽  
Vibrationally Excited ◽  
Model Calculations ◽  
F Region ◽  
Neutral Temperature ◽  
The Difference ◽  
Excited Nitrogen

Abstract. We present a comparison of the observed behavior of the F-region ionosphere over Millstone Hill during the geomagnetically quiet and storm periods of 6–12 April 1990 with numerical model calculations from the IZMIRAN time-dependent mathematical model of the Earth's ionosphere and plasmasphere. The major enhancement to the IZMIRAN model developed in this study is the use of a new loss rate of O+(4S) ions as a result of new high-temperature flowing afterglow measurements of the rate coefficients K1 and K2 for the reactions of O+(4S) with N2 and O2. The deviations from the Boltzmann distribution for the first five vibrational levels of O2(v) were calculated, and the present study suggests that these deviations are not significant. It was found that the difference between the non-Boltzmann and Boltzmann distribution assumptions of O2(v) and the difference between ion and neutral temperature can lead to an increase of up to about 3 or a decrease of up to about 4 of the calculated NmF2 as a result of a respective increase or a decrease in K2. The IZMIRAN model reproduces major features of the data. We found that the inclusion of vibrationally excited N2(v > 0) and O2(v > 0) in the calculations improves the agreement between the calculated NmF2 and the data on 6, 9, and 10 April. However, both the daytime and nighttime densities are reproduced by the IZMIRAN model without the vibrationally excited nitrogen and oxygen on 8 and 11 April better than the IZMIRAN model with N2(v > 0) and O2(v > 0). This could be due to possible uncertainties in model neutral temperature and densities, EUV fluxes, rate coefficients, and the flow of ionization between the ionosphere and plasmasphere, and possible horizontal divergence of the flux of ionization above the station. Our calculations show that the increase in the O+ + N2 rate factor due to N2(v > 0) produces a 5-36 decrease in the calculated daytime peak density. The increase in the O++ O2 loss rate due to vibrational-ly excited O2 produces 8-46 reductions in NmF2. The effects of vibrationally excited O2 and N2 on Ne and Te are most pronounced during the daytime.Key words. Ion chemistry and composition · Ionosphere – atmosphere interactions · Ionospheric disturbances

scholarly journals Numerical Investigation on the Water Entry of Several Different Bow-Flared Sections

2020 ◽  
Vol 10 (22) ◽  
pp. 7952
Author(s):  
Qiang Wang ◽  
Boran Zhang ◽  
Pengyao Yu ◽  
Guangzhao Li ◽  
Zhijiang Yuan
Keyword(s):  
Stokes Equations ◽  
Water Entry ◽  
Navier Stokes ◽  
Hydrodynamic Characteristics ◽  
Time Step ◽  
Navier Stokes Equations ◽  
Surface Evolution ◽  
Mesh Method ◽  
The Difference ◽  
Dynamics Method

The bow-flared section may be simplified in the prediction of slamming loads and whipping responses of ships. However, the difference of hydrodynamic characteristics between the water entry of the simplified sections and that of the original section has not been well documented. In this study, the water entry of several different bow-flared sections was numerically investigated using the computational fluid dynamics method based on Reynolds-averaged Navier–Stokes equations. The motion of the grid around the section was realized using the overset mesh method. Reasonable grid size and time step were determined through convergence studies. The application of the numerical method in the water entry of bow-flared sections was validated by comparing the present predictions with previous numerical and experimental results. Through a comparative study on the water entry of one original section and three simplified sections, the influences of simplification of the bow-flared section on hydrodynamic characteristics, free surface evolution, pressure field, and impact force were investigated and are discussed here.

scholarly journals Comparison of the Changes in the Structure of the Transverse Arch of the Normal and Hallux Valgus Feet under Different Loading Positions

2019 ◽  
Vol 2 (1) ◽  
pp. 3 ◽  
Author(s):  
Hala Zeidan ◽  
Yusuke Suzuki ◽  
Yuu Kajiwara ◽  
Kengo Nakai ◽  
Kanako Shimoura ◽  
...  
Keyword(s):  
Hallux Valgus ◽  
Weight Bearing ◽  
Quiet Standing ◽  
Arch Height ◽  
Imaging Device ◽  
Transverse Arch ◽  
Weight Shift ◽  
Structural Differences ◽  
The Difference ◽  
Imagej Software

The transverse arch of the foot receives and transfers loads during gait. We aim to identify the difference in its structure between normal feet and hallux valgus (HV) feet and the effects of loading. Two groups, Without-HV and With-HV (HV ≥ 20°), were assessed using a weight-bearing plantar ultrasound imaging device to view the structure of the transverse arch. Measurements were recorded in sitting, quiet standing, and 90% weight-shift (90% W.S.) loading positions on the tested foot. Images were then processed using ImageJ software to analyze the transverse arch length (TAL), the length between the metatarsal heads (MTHs), transverse arch height (TAH), and the height of each MTH. TAL significantly increased in all positions in the With-HV group compared to that in the Without-HV group. It also increased in both groups under loading. TAH was not significantly higher in the With-HV group than in the Without-HV group in sitting and standing positions, except in the 90% W.S position, where both groups showed similar results. TAH decreased in both groups under loading. In summary, the structure of the transverse arch changes in HV feet and under loading conditions. This finding will help understand the structural differences between normal and HV feet and help resolve shoe fit problems in individuals with HV deformity.

Ontogeny and heterochrony in the ostracode Cavellina Coryell from Lower Permian rocks in Kansas

Paleobiology ◽  
1986 ◽  
Vol 12 (3) ◽  
pp. 290-301 ◽  
Author(s):  
Peter N. Schweitzer ◽  
Roger L. Kaesler ◽  
G. P. Lohmann
Keyword(s):  
Life Histories ◽  
Morphological Difference ◽  
Structural Difference ◽  
Lower Permian ◽  
Closely Related Species ◽  
Know How ◽  
Taxonomic Level ◽  
Yield Information ◽  
Structural Differences ◽  
The Difference

Animals evolve by changing their form and by changing the rate at which they develop. Since evolution of development through time may be directly related to the adaptation of their life histories, study of ontogeny in fossils may yield information about the ecology of extinct animals. We need to know how to measure animals' ontogeny and at what taxonomic level structural differences overshadow differences in development. Two closely related species of the Permian ostracode Cavellina were compared to determine how much of the morphological difference between them is due to differences in their ontogenies. Most of the difference is not related to ontogeny. They also differ in a way that could be explained by heterochrony, although this difference is secondary in importance to the structural difference. These findings suggest that ecological adaptation might best be studied by examining the changes in development that occur within species through time and space.

REASONS TO BELIEVE AND REASONS TO ACT

Episteme ◽  
2016 ◽  
Vol 13 (4) ◽  
pp. 427-438 ◽  
Author(s):  
Stewart Cohen
Keyword(s):  
Rational Requirement ◽  
Structural Differences ◽  
The Difference

ABSTRACTI consider the structural differences between reasons to believe and reasons to act. I argue that Mark Schroeder's project of providing a unified account of reasons to believe and reasons to act faces serious difficulties. I also investigate the difference between rational requirement and rational permission. While the difference between these notions in the case of action is a matter of the strength of one's reasons, I argue that in the case of belief, the difference depends on what one is attending to.

scholarly journals A New Method to Estimate the Systematical Biases of Expendable Bathythermograph

2011 ◽  
Vol 28 (2) ◽  
pp. 244-265 ◽  
Author(s):  
Lijing Cheng ◽  
Jiang Zhu ◽  
Franco Reseghetti ◽  
Qingping Liu
Keyword(s):  
Standard Deviation ◽  
Integral Method ◽  
Differential Method ◽  
Rate Coefficients ◽  
Temperature Error ◽  
Temperature Profiles ◽  
Fall Rate ◽  
Start Up ◽  
The Mean ◽  
The Individual

Abstract A new technique to estimate three major biases of XBT probes (improper fall rate, start-up transient, and pure temperature error) has been developed. Different from the well-known and standard “temperature error free” differential method, the new method analyses temperature profiles instead of vertical gradient temperature profiles. Consequently, it seems to be more noise resistant because it uses the integral property over the entire vertical profile instead of gradients. Its validity and robustness have been checked in two ways. In the first case, the new integral technique and the standard differential method have been applied to a set of simulated XBT profiles having a known fall-rate equation to which various combinations of pure temperature errors, random errors, and spikes have been added for the sake of this simulation. Results indicated that the single pure temperature error has little impact on the fall-rate coefficients for both methods, whereas with the added random error and spikes the simulation leads to better results with the new integral technique than with the standard differential method. In the second case, two sets of profiles from actual XBT versus CTD comparisons, collected near Barbados in 1990 and in the western Mediterranean (2003–04 and 2008–09), have been used. The individual fall-rate coefficients and start-up transient for each XBT profile, along with the overall pure temperature correction, have been calculated for the XBT profiles. To standardize procedures and to improve the terms of comparison, the individual start-up transient estimated by the integral method was also assigned and included in calculations with the differential method. The new integral method significantly reduces both the temperature difference between XBT and CTD profiles and the standard deviation. Finally, the validity of the mean fall-rate coefficients and the mean start-up transient, respectively, for DB and T7 probes as precalculated equations was verified. In this case, the temperature difference is reduced to less than 0.1°C for both datasets, and it randomly distributes around the null value. In addition, the standard deviation on depth values is largely reduced, and the maximum depth error computed with the datasets near Barbados is within 1.1% of its real value. Results also indicate that the integral method has a good performance mainly when applied to profiles in regions with either a very large temperature gradient, at the thermocline or a very small one, toward the bottom.

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