The normal spermatogenetic wave-cycle in Peromyscus

1947 ◽  
Vol 99 (2) ◽  
pp. 163-175 ◽  
Author(s):  
Ray Moree
Keyword(s):  
Wave Cycle

scholarly journals Renovation cycle diagram

Vestnik MGSU ◽  
2021 ◽  
pp. 1088-1094
Author(s):  
Leonid V. Kievskiy ◽  
Yakov I. Kievskiy
Keyword(s):  
Schematic Model ◽  
City Development ◽  
Actual Duration ◽  
Flow Processes ◽  
Wave Cycle ◽  
Multiple Process ◽  
New Form ◽  
Line Construction ◽  
Center City ◽  
Cycle Diagram

Introduction. A relatively new form of transformation of the territory in the current urban development, the renovation of quarters, requires close scientific study and methodological justification. Renovated neighborhoods, as well as projects for the construction of new houses, have individual features and characteristics. The authors hypothesize that, despite the variety of characteristics of renovated neighborhoods and projects for the construction of new houses, traditional in-line construction with the allocation of characteristic stages is possible. Materials and methods. To study the actual duration of the stages of creating objects under the renovation program (which is necessary to identify objects of similar duration), a special database was formed in the Scientific and Project Center “City Development”. As of 15.05.2021, 313 objects involved in the renovation program are included in this special database. A thorough verification of the specified database was performed. As a result, 122 objects with a spread of construction duration values from 11 months to 43.2 months are stored in the verified database. In addition, the materials of the information system for ensuring urban planning activities (ISOGD) of Moscow were used. The initial materials allowed us to identify a number of characteristic stages in the renovation program for each object. Results. To analyze the design duration of construction, the set of objects is divided into 2 parts: commissioning in 2021 and commissioning in subsequent years. For each part, histograms of the distribution of the duration of construction of houses during renovation are constructed and it is proved that the law of normal distribution is observed. A schematic model of renovation processes with multiple process durations is presented. The overall duration of the design (project stage) can take 1 year, construction — 2 years, and the combined stages: preparation of documents, relocation and demolition, will approximately take 1 year. This four-year wave cycle is then repeated the required number of times. The calendar plan of renovation for three wave objects with the allocation of the leading stream is presented. The ratio of flow processes during renovation is most clearly reflected in the constructed cyclogram of a multi-rhythmic object flow modified for renovation conditions. Combined schedules of renovation of in-line construction are constructed. Conclusions. Despite the considerable variety of renovated neighborhoods and projects for the construction of new houses, the authors of the article prove that traditional in-line construction with the allocation of characteristic stages is possible. For large contracting organizations, it is realistic to form a multi-rhythmic object flow with the allocation of the construction stage as the leading flow and calculate the renovation cyclogram.

Electron-density maps

2002 ◽  
Author(s):  
David Blow
Keyword(s):  
Fourier Transform ◽  
Electron Density ◽  
Three Dimensional ◽  
Two Dimensions ◽  
Unit Cell ◽  
Density Maps ◽  
Wave Cycle ◽  
Density Map ◽  
The Fourier Transform ◽  
Electron Density Map

When everything has been done to make the phases as good as possible, the time has come to examine the image of the structure in the form of an electron-density map. The electron-density map is the Fourier transform of the structure factors (with their phases). If the resolution and phases are good enough, the electron-density map may be interpreted in terms of atomic positions. In practice, it may be necessary to alternate between study of the electron-density map and the procedures mentioned in Chapter 10, which may allow improvements to be made to it. Electron-density maps contain a great deal of information, which is not easy to grasp. Considerable technical effort has gone into methods of presenting the electron density to the observer in the clearest possible way. The Fourier transform is calculated as a set of electron-density values at every point of a three-dimensional grid labelled with fractional coordinates x, y, z. These coordinates each go from 0 to 1 in order to cover the whole unit cell. To present the electron density as a smoothly varying function, values have to be calculated at intervals that are much smaller than the nominal resolution of the map. Say, for example, there is a protein unit cell 50 Å on a side, at a routine resolution of 2Å. This means that some of the waves included in the calculation of the electron density go through a complete wave cycle in 2 Å. As a rule of thumb, to represent this properly, the spacing of the points on the grid for calculation must be less than one-third of the resolution. In our example, this spacing might be 0.6 Å. To cover the whole of the 50 Å unit cell, about 80 values of x are needed; and the same number of values of y and z. The electron density therefore needs to be calculated on an array of 80×80×80 points, which is over half a million values. Although our world is three-dimensional, our retinas are two-dimensional, and we are good at looking at pictures and diagrams in two dimensions.

Two-Dimensional Model for Wave-Induced Pore Pressure Accumulation in Marine Sediments

2013 ◽  
Author(s):  
Hongyi Zhao ◽  
Dong-Sheng Jeng ◽  
Huijie Zhang ◽  
Jisheng Zhang
Keyword(s):  
Pore Pressure ◽  
Marine Sediments ◽  
Wave Motion ◽  
Present Model ◽  
Two Dimensional ◽  
New Model ◽  
One Dimensional ◽  
Wave Cycle ◽  
Previous Solution ◽  
Wave Induced

In this paper, a two-dimensional (2D) porous model is established to investigate the predication of the wave-induced pore pressure accumulations in marine sediments. In the new model, the VARANS equation is used as the governing equation for the wave motion, while the Biot’s consolidation theory is used for porous seabed. The present model is verified with the previous experimental data [1] and provides a better prediction of pore pressure accumulation than the previous solution [2]. With the new model, a 2D liquefied zone is formed at the beginning of the process, and then gradually move down. After a certain wave cycle (for example, 30 wave cycles in the numerical example), the liquefaction zone will become one-dimensional (1D) and continuously move down and eventually approaches to a constant. Numerical results also conclude the maximum liquefaction depth increases as wave height increases and in shallow water.

scholarly journals Automated Gastric Slow Wave Cycle Partitioning and Visualization for High-resolution Activation Time Maps

2010 ◽  
Vol 39 (1) ◽  
pp. 469-483 ◽  
Author(s):  
Jonathan C. Erickson ◽  
Greg O’Grady ◽  
Peng Du ◽  
John U. Egbuji ◽  
Andrew J. Pullan ◽  
...  
Keyword(s):  
High Resolution ◽  
Slow Wave ◽  
Activation Time ◽  
Gastric Slow Wave ◽  
Wave Cycle

scholarly journals On beach cusp formation

2008 ◽  
Vol 597 ◽  
pp. 145-169 ◽  
Author(s):  
NICHOLAS DODD ◽  
ADAM M. STOKER ◽  
DANIEL CALVETE ◽  
ANURAK SRIARIYAWAT
Keyword(s):  
Evolution Equation ◽  
Shallow Water Equations ◽  
Normal Wave ◽  
Feedback Mechanism ◽  
Physical Mechanisms ◽  
Wave Cycle ◽  
Bed Evolution ◽  
Positive Feedback Mechanism ◽  
Beach Cusp ◽  
Wave Incidence

A system of shallow water equations and a bed evolution equation are used to examine the evolution of perturbations on an erodible, initially plane beach subject to normal wave incidence. Both a permeable (under Darcy's law) and an impermeable beach are considered. It is found that alongshore-periodic morphological features reminiscent of swash beach cusps form after a number of incident wave periods on both beaches. On the permeable (impermeable) beach these patterns are accretional (erosional). In both cases flow is ‘horn divergent’. Spacings of the cusps are consistent with observations, and are close to those provided by a standing synchronous linear edge wave. An analysis of the processes leading to bed change is presented. Two physical mechanisms are identified: concentration gradient and flow divergence, which are dominant in the lower and upper swash respectively, and their difference over a wave cycle leads to erosion or deposition on an impermeable beach. Infiltration enters this balance in the upper swash. A bed wave of elevation is shown to advance up the beach at the tip of the uprush, with a smaller wave of depression on the backwash. It is found that cusp horns can grow by a positive feedback mechanism stemming from decreased (increased) backwash on positive (negative) bed perturbations.

Snap-Stabilizing Wave Algorithm with Multiple Initiators in Arbitrary Networks

2014 ◽  
Vol 905 ◽  
pp. 619-622 ◽  
Author(s):  
Ganesh Nandakumaran ◽  
Mehmet Hakan Karaata
Keyword(s):  
External Input ◽  
M Wave ◽  
Wave Cycle ◽  
Distributed Execution ◽  
Feedback Phase

A wave is a distributed execution, often made up of a broadcast phase followed by a feedback phase, requiring the participation of all the system processes before a particular event called decision is taken. Solutions to a large number of problems such as globalsnapshots can be solved efficiently using multiple concurrent initiators. In this paper, we propose an optimal snapstabilizing algorithm, referred to as an mwave algorithm, that would be initiated by one or more initiator processes, essentially forming a collection of individual waves. Having multiple initiators enables a better reach and faster completion of broadcasted messages as a result. Our algorithm differs from existing multi-node broadcasting techniques in a few notable ways, such as working in any arbitrary network and having dynamic initiator processes that participate in an m-wave cycle depending on the presence of an external input. Being snap-stabilizing ensures the proposed algorithm always behaves according to its specification.

On Safety and Reliability for Platforms That are Unmanned During Severe Storms

2013 ◽  
Author(s):  
Øistein Hagen ◽  
Gunnar Solland
Keyword(s):  
Life Extension ◽  
Risk Level ◽  
Height Distribution ◽  
State Variables ◽  
Limit States ◽  
Structural Requirements ◽  
Acceptance Criterion ◽  
Existing Structures ◽  
Safety And Reliability ◽  
Wave Cycle

The paper addresses safety and reliability issues for platforms where an unmanning strategy is premised. The standard NORSOK N-006 recommends how to deal with the specific aspects that engineers meet when assessing existing structures, including life extension. A possible mitigating measure for structures that do not meet today’s structural requirements for environmental loads is to unman the platform during storms. The basis for the unmanning criteria in this standard is that the safety for personnel on a platform that needs to be unmanned during storms is consistent with the safety for personnel on platforms that satisfy structural requirements for manned platforms. The prevailing metocean conditions at a North Sea location is modeled by a storm statistics approach. The capacity waves according to the codes checks are calculated for a jacket structure and the limiting metocean conditions that comply with the acceptance criterion are established. The expected frequency of unmanning events is determined, and the issue of forecast uncertainty discussed. The annual maximum wave height distribution for the location is compared with the corresponding distribution that applies when the platform is manned, i.e. for metocean conditions that do not trigger unmanning. The probability of failure for important limit states is calculated on condition that no unmanning is required, and for a platform that satisfies the requirements for manned platforms. The most likely realizations of sea state variables and extreme wave cycle are determined for the different cases. Parts of the structure may be loaded into the non-linear range and consequently the load-carrying resistance of the structure against future load cycles may be reduced. In such cases it is required to carry out a check of the cyclic capacity of the structure. The statistics for the second highest wave during storm conditions is investigated for unmanning scenarios and for a platform that satisfies the requirements for manned platforms. It is normally acknowledged that the structural failure probability associated with normal statistical variations is considerably less than the failures that are due to gross errors. The difference in risk due to gross errors between platforms that are operated as unmanned during storms compared to the gross error risk level for manned platforms is discussed.

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