Rastrigin function: Difference between revisions

From formulasearchengine
Jump to navigation Jump to search
remove {{mathanalysis-stub}}
en>Mark viking
top: Added wl
 
Line 1: Line 1:
{{confusing|date=June 2010}}
If you purchase a knife that you really love you'll want to discover things to apply it to — and that’s when a pocket knife moves from crap in your pocket, to a necessary software. I’ve talked a lot about knives in the past and even supplied just a few causes to carry a pocket knife everyday, but I don’t think I’ve convinced everybody just yet — so let’s try and try this now. Blade size Ideally it's best to attempt to maintain this under three-inches, most US States and Cities have [http://Sas.optimaltoolkit.com/index.php/Spyderco_Delica_Knife_Review rules surrounding] knives over 3.5 inches, so be sure to look that up on your space.<br><br>It has unfold like a virus throughout the trade. But if I have been a financial analyst I'd inform you that's solely his SECOND biggest invention. His real innovation is creating a market space where he can readily sell tons of of high end manufacturing knives that START at $350. The great thing about what Chris Reeve did is similar [http://www.thebestpocketknifereviews.com/spyderco-knives-review/ Www.Thebestpocketknifereviews.Com] to what Starbucks did-he was in a position to convince consumers that there's worth in paying 300% more for one thing fairly primary. But in contrast to Starbucks, which makes dreadfully overroasted and overflavored espresso devoid of any subtlety, Chris Reeve used just about unmatched high quality and consistency to persuade customers. Holding a Sebenza.<br><br>You can purchase scale specific model trees, however they're very expensive when making an attempt to fill a big show with lifelike scenery components. Tree kits are rather less pricey and are useful for those with dexterity issues. If you are physically in a position, have a number of hours to spend and luxuriate in a hands-on approach - then making your own trees can be both fun and a money saving approach to deliver your [http://Wachstumswende.sinnwerkstatt.com/index.php?title=Spyderco_Ambitious_Vs_Tenacious mannequin railroad] to life. Twigs and small branches which have broken from timber are likely to have more jagged ends than pine cones. When needed, use a pocket or utility knife to chop away any jagged ends.<br><br>Men have been carrying pocket knives for hundreds of years. But with elevated safety on the airport and different buildings, knives have been disappearing from males’s pockets. Yet these minor obstacles are not ample purpose to give up carrying a knife completely. The carrying of a pocket knife is a man [http://www.thebestpocketknifereviews.com/spyderco-knives-review/ Spyderco Bug Knife Review] custom that should be continued. Why a Man Should Carry a Pocket Knife Jack knife. A [http://doc.Froza.ru/index.php/Disassemble_Spyderco_Tenacious jack knife] has a easy hinge at one finish, and will have a couple of blade. The jack knife is in style among hunters, fishermen, and campers.<br><br>A camper trailer is a small, towable camper. It is normally pulled behind a car, much like a boat trailer. When in use, the camper is prolonged right into a full-dimension tent, which sometimes features a mattress and a table. Like traditional tents, a camper trailer requires regular maintenance. A gap [http://www.victorinox.com/ch custom knife makers] in a [http://Esmikorea.Ezconn.net/xe/?document_srl=70076 camper trailer] is simply as unpleasant as a gap in a conventional tent. A gap on the roof can expose you to outdoors insects and rain. To guard yourself from a disastrous tenting expertise, repair the hole on your camper trailer [http://trac.Edgewall.org/newticket?reporter=anonymous&version=0.12.5&summary=TimeoutError%3A+Unable+to+get+database+connection+within+0+seconds.&description=Due+to+the+fact+1935%2C+New+Graham+Knives+has+been+the+top+supply+for+high+quality+knives+and+accessories.+We+are+the+%5Bhttp%3A%2F%2FWordpress.org%2Fsearch%2Fpremier%2Bknife+premier+knife%5D+and+cutlery+supplier+around%2C+providing+more+than+100+brands+of+the+finest+goods+obtainable.+New+Graham+Knives+has+just+about+every+knife+imaginable%2C+from+fixed+blade+and+locking+knives%2C+to+kitchen+knives+and+knife+care+accessories.+With+a+completely+stocked+on-line+retailer%2C+discovering+the+knife+you+need+to+have+has+never+been+a+lot+easier.%0D%0A%0D%0AInstead+of+a+thumb+stud%2C+the+blade+sports+a+good+large+thumb+hole+that+is+terrific+for+a+%5Bhttp%3A%2F%2FWww.Wikipedia.org%2Fwiki%2Fsingle%2Bhanded+single+handed%5D+opening.+This+was+my+first+knife+with+a+thumb+hole%2C+and+I+actually+like+it+a+lot+better+than+a+thumb+stud.+When+the+knife+very+first+arrived+it+was+mind+blowingly+razor+sharp+with+a+convex+edge.+I+nonetheless+don%27t+forget+cutting+some+plastic+packaging+with+it%2C+and+the+blade+slid+by+means+of+it+with+such+ease%2C+I+could+not+think+it.+The+crucible+steel+good+quality+hollow+ground+CPM-M4+blade+measures+3.438%E2%80%B3+with+an+all+round+length+8.078%E2%80%B3.+It+weighs+four.eight+oz.+Fantastic+for+camping%2C+cutting+rope%2C+branches+and+even+for+cutting+meat+and+paper%2C+this+knife+received+a+9.six+out+of+ten+for+top+quality+and+a+9.8+for+value+for+the+money.+The+knife+stays+folded+up+tight%2C+and+feels+secure+when+open%0D%0A%0D%0AThe+Paramilitary+two+is+regarded+by+several+in+the+neighborhood+as+Spyderco%27s+best+folding+knife.+It+achieves+close+to+perfection+for+a+high+quality%2C+difficult+use+EDC+knife.+The+Para+2+is+somewhat+substantial+%28+8.2%E2%80%B3+inches+when+opened+with+a+3.+If+you+liked+this+write-up+and+you+would+like+to+obtain+extra+data+about+%5Bhttp%3A%2F%2Fwww.thebestpocketknifereviews.com%2Fspyderco-knives-review%2F+Spyderco+Native+Knife+Review%5D+kindly+visit+the+web-page.+4%E2%80%B3+blade+%29+but+really+lightweight+for+its+size+%28+three.75+ounces+%29.+The+blade+is+created+from+the+really+well-known+S30V+steel+with+a+complete+flat+grind.+The+blade%2C+like+most+Spyderco+knives%2C+comes+hair+shaving+sharp+right+from+the+factory%2C+and+being+such+a+higher+high-quality+steel+will+hold+this+edge+sharpness+for+longer+periods+of+time+in+the+course+of+common+use.%0D%0A%0D%0A%5Bhttp%3A%2F%2FWww.Adobe.com%2Fcfusion%2Fsearch%2Findex.cfm%3Fterm%3D%26Spyderco%2BEndura%26loc%3Den_us%26siteSection%3Dhome+Spyderco+Endura%5D+4+Green.+5+closed+lockback.+3+3%2F4%22+VG-10+stainless+full+flat+ground+blade+with+thumb+hole+pull.+Vibrant+green+fiberglass+reinforced+nylon+handles+with+Bi-Directional+Texturing+for+a+slip-free+tactile+traction.+Black+stainless+pocket+clip.%22+1+%2480.40+Endura+4+brown+SC10FPBN+39+Flat+Ground+Brown+FRN+Spyderco+Manix+2.+4+5%2F8+closed.+154CM+stainless+partially+serrated+blade+with+thumb+hole.+Features+ball+bearing+lock+blade+locking+mechanism.+Black+G-10+handles+with+enlarged+lanyard+hole.+Reversible+stainless+pocket+clip.%22+1+%2498.40+Spyderco+Centofante+III+-+SC66PBK3+%2477.90+Spyderco+ENDURA+FLATGR+P%3BN+ORANGE+FRN+-+C10FPOR+%2480.40+Spyderco+Manix+2+Translucent+Serrated+Knife+C101PSBL2+%2485.40+Spyderco+Manix+2+Translucent+Knife+C101PBL2+BLADE+AND+HANDLE&create=Create roof earlier] than your subsequent journey.<br><br>Some individuals will notice that Nokia is constructing a special relationship with Microsoft, to the purpose where the manufacturer is ready to deliver extra exclusive options in its phones and push for issues to be added in later revisions. For those who're a WP fan, then there is perhaps an argument for committing to Nokia with a view to benefit from all those good issues to return. Nonetheless, we expect that is untimely. Drive is a pleasant exclusive feature, however there's not much else but. The Nokia-Microsoft relationship will definitely change into extra essential, but that's not sufficient to sway a buying resolution as we speak.<br><br>Due to right this moment’s know-how, even urban dwellers can carry around a small bit of survival tools. There are a number of very superb tools made which can be carried in a wallet or purse. These tolls are often referred to pocket survival instruments. Simply because you spend most of your time in the city, doesn’t mean you should be unprepared for emergency conditions. There may be all the time room in your purse or pockets for a pocket survival device of some kind. Loflin is charged with one depend of assault with a lethal weapon with intent to kill inflicting serious injury and one rely of misdemeanor assault on a handicapped individual.<br><br>To reattach the door slab, simply lift the door into the track whereas gripping it from the sides and lining up the pivot clips on the door slab to the pivot bolts on the wheeled monitor guides, clipping and then locking them in place. Now the door should swing freely back into place within the pocket. Modify the pivot bolts as wanted to make the door slab flush with the jamb. Reattach the door trim for a wonderfully [http://www.crkt.com/pocketknives gerber folding knives] working pocket door. California over state lines may get you into trouble with federal legal guidelines or legal guidelines of other states. Native ordinances may additionally impact the legality of your knife.
 
'''First-break picking ''' detecting or picking the onset arrivals of refracted signals from all the signals received by receiver arrays and produced by a particular source signal generation. It is also called first arrival picking or first break detection. First-break picking can be done automatically, manually or as a combination of both. With the development of computer science and the size of seismic surveys, automatic picking is often preferred.<ref name=Yilmaz/>
 
==Significance==
'''First-break picks''' associated with the [[refracted]] arrival times are used in an [[Inversion (geology)|inversion scheme]] to study the near-surface low-[[velocity]] zone and subsequent determination of static corrections.
Static correction is a correction applied to geophysical data, especially seismic data, to compensate for the effect of near-surface irregularities, differences in the elevation of shots and [[geophone]]s, or any application to correct the positions of source and receivers.
 
==History of First Break Picking==
Gelchinsky and Shtivelman<ref name=Gelchinsky/>(1983) used [[correlation]] properties of signals and applied a statistical criterion for the estimation of first arrivals time.
 
Coppens<ref name=Coppens/>(1985) calculated the ratio of energy of [[seismogram]] of the two windows and used that to differentiate in signal and noise.
 
Michael D. McCormark ''et al.''<ref name=Michael/>(1993) introduced a [[backpropagation]] neural network (BNN) method. The [[Neural network]] which edits [[seismic]] data or pick first breaks was trained by users, who were just selecting and presenting to the network examples of trace edits or refraction picks. The network then changes internal weights iteratively until it can reproduce the examples accurately provided by the users.
 
Fabio Boschetti ''et al.''<ref name=Fabio/>(1996) introduce a [[fractal]]-based [[algorithm]] which detects the presence of a signal by analyzing the variation in fractal dimension along the trace. This method works when signal-to-noise ratio is small, but it is considerably slow.
 
A direct correlation method was introduced by Joseph ''et al.''<ref name=Joseph/>(1999) which was developed for use in highly time-resolved, low-noise signals acquired in the laboratory. In this method, the greatest value of Pearson's correlation coefficient between segments of observed [[waveform]]s near the [[pulse onset]] and at an appropriate reference serves as the time determination criterion.
 
Zuolin Chen, ''et al.''<ref name=Zuolin/>(2005) introduced a multi-window algorithm to detect the first break. In this method, three moving windows were used and the averages of absolute amplitudes in each window need to be calculated, then ratios based on the averages of the windows provide standards to differentiate signals from unwanted noise.
 
Wong ''et al.''<ref name=Wong/>(2009) introduced STA/LTA ratio method. This method is similar as Coppens’<ref name=Coppens/> algorithm. The difference is to do the ratio of two averages of energy between a short-term window and a long-term window, which is denoted as STA/LTA (short-term average/long-term average), instead of calculating the ratio of energy of seismogram of the two windows in Coppens’ algorithm.
 
==Methods of Automatic First Break Picking==
===STA/LTA ratio Method<ref name=Wong/>===
This method is similar as Coppens’ (1985) algorithm. The difference is to do the ratio of two averages of energy between a short-term window and a long-term window, which is denoted as STA/LTA (short-term average/long-term average), instead of calculating the ratio of energy of seismogram of the two windows in Coppens’ algorithm. The numerical [[derivative]] of the ratio can be defined as,
: <math>\begin{align}
  & d_i=r_{i+1}-r_i , i=1,2,...(n-1)    \\
  \end{align}</math>
where ''r<sub>i+1</sub>'' is the STA/LTA ratio at time index ''i+1'', and ''r<sub>i</sub>''  is the STA/LTA ratio at time index ''i''. For noise-free seismograms, the maximum value of the numerical derivative of the STA/LTA ratio is close to the time of the first arrival.
 
Wong et al. (2009) modified the algorithm of the energy ratio method, where they named the method as modified energy ratio. In this method, they define the energy ratio as,
: <math>\begin{align}
& er=\sum_{j=i-ne}^i
    x^2_j/\sum_{j=i}^{i+ne}
    x^2_j \\
  \end{align}</math>
where ''x<sub>i</sub>'' is the times series representing a seismogram with the time index ''i=1, 2 … N.'' and the number of points in an energy window is ''ne''. Then, the modified energy ratio is defined as
: <math>\begin{align}
  & er3_i=(abs(x_i)^*er)^3 \\
  \end{align}</math>
The peak of the modified energy ratio ''er3i'' is very closed to the time of first arrivals on noise-free seismograms.
 
=== Multi-Window Method<ref name=Zuolin/>===
This method needs to calculate the averages of absolute [[amplitude]]s from a seismic trace by using three moving time windows before and after each time point (sample).
 
When the instantaneous absolute amplitude exceeds an automatically adjusted threshold, ratios based on the averages of the windows over previous time samples provide standards to differentiate signals from unwanted noise.
 
The multi-window automatic P phase picker operates in the time-domain. It includes procedures to define: time windows, standards, corresponding thresholds and [[waveform]] correction.
 
1. The averages of absolute amplitudes within BTA (Before Term Average), ATA (After Term Average) and DTA (Delayed Term Average) windows are respectively defined as follows:
: <math>\begin{align}
  &\overline{BTA(t)}=\sum_{i=i}^{m}\frac{|u(t-i)|}{m}\\
  &\overline{ATA(t)}=\sum_{i=i}^{n}\frac{|u(t+j)|}{n}\\
  &\overline{DTA(t)}=\sum_{k=i}^{q}\frac{|u(t+j+d)|}{q}\\
  &R_2(t)=\frac{\overline{ATA(t)}}{\overline{BTA(t)}}\\
  &R_3(t)=\frac{\overline{DTA(t)}}{\overline{BTA(t)}}\\
  \end{align}</math>
Standards ''R<sub>2</sub>(t)'' and ''R<sub>3</sub>(t)'' are used for the discrimination of high-amplitude short-duration and long-duration noise.
 
2.Thresholds is defined as
: <math>\begin{align}
  & H_1(t)=E_m(t-p)+\alpha E_{sd}(t-p) \\
  \end{align}</math>
where ''E<sub>m</sub>'' is mean and ''E<sub>sd</sub>'' is [[standard deviation]]; ''p'' is the number of shifted samples; ''α'' is the coefficient to adjust the height of the first threshold and is taken to be 3. From this equation it is obvious that ''H<sub>1</sub>(t)'' is automatically adjusted with the variance of the background noise.
 
3. ''H<sub>1</sub>(t)'' is defined larger than most pre-existing noise levels, and the instantaneous absolute amplitude at the trigger time point is higher than ''H<sub>1</sub>(t)'',according to the configuration of the first arrival of an event the real onset time must be earlier than the trigger time point. A waveform correction should be used to compensate this belated onset time. For an impulsive first arrival, the height of the absolute amplitude and the representative [[gradient]] at the trigger point can be used to accomplish the correction.
 
==Available Code==
Potash SU is a package including [[Seismic Unix]] style codes developed by Balazs Nemeth, it provides a [[subroutine]] called simple window-based first break picker, the figure shows the seismic images before and after the application of subroutine.
[[File:Wagc=1.PNG|thumb|Right one is before first break picking, left one is after first break picking]]
 
==Future Trend of the Topic==
Methods of Picking: the automatic first-break picking has been playing a more important role in processing the seismic data, and directly influences the authenticity of the seismic sections. Because of the increasing of [[seismic survey]] size, more efficient and fast first break picking method will be needed, and with the development of computer science, the method which can be paralleled will be preferred.
 
Application of First Break: Traditionally the [[geologist]]s use the first break to do the static correction. First break signal can also be used as the observation data to do the history matching.
 
== Notes ==
<!--- See [[Wikipedia:Footnotes]] on how to create references using <ref></ref> tags which will then appear here automatically -->
{{reflist|refs=
<ref name=Coppens>Coppens F., (1985). ''First arrival picking on common-offset trace collections for automatic estimation of static corrections.'' Geophysical Prospecting, 33, 1212-1231.</ref>
<ref name=Fabio>Fabio Boschetti, Mike D. Dentith, and Ron D. List, (1996). ''A fractal-based algorithm for detecting first arrivals on seismic traces.'' Geophysics, Vol.61, No.4, P. 1095-1102.</ref>
<ref name=Gelchinsky>Gelchinsky B. and Shtivelman V., (1983). ''Automatic picking of first arrivals and parameterization of traveltime curves.'' Geophysical Prospecting, 31, 915-928.</ref>
<ref name=Joseph>Joseph B. Molyneux and Douglas R. Schmitt, (1999). ''First-break timing: Arrival onset times by direct correlation.'' Geophysics, Vol.64, No.5, P. 1492-1501.</ref>
<ref name=Michael>Michael D. McCormack et al, (1993). ''First-break refraction event picking and seismic data trace editing using neural networks.'' Geophysics, Vol.58, No.1, P. 67-78.</ref>
<ref name=Yilmaz>ÖZ, YILMAZ, (2000). ''Seismic Data Analysis: Processing, Inversion, and Interpretation of Seismic Data.'' Volume Ⅰ: Society of Exploration Geophysicists.</ref>
<ref name=Wong>Wong J., Han L., Bancroft J.C., Stewart R.R., (2009). ''Automatic time-picking of first arrivals on noisy microseismic data.[http://www.crewes.org/ForOurSponsors/ConferenceAbstracts/2009/CSEG/Wong_CSEG_2009.pdf]''</ref>
<ref name=Zuolin>Zuolin Chen and Robert Stewart, (2005). ''Multi-window algorithm for detecting seismic first arrivals.[http://www.crewes.org/ForOurSponsors/ConferenceAbstracts/2005/CSEG/Chen_CSEG_2005-1.pdf]''</ref>
}}
 
[[Category:Acoustics]]
[[Category:Seismology]]

Latest revision as of 00:44, 4 September 2014

If you purchase a knife that you really love you'll want to discover things to apply it to — and that’s when a pocket knife moves from crap in your pocket, to a necessary software. I’ve talked a lot about knives in the past and even supplied just a few causes to carry a pocket knife everyday, but I don’t think I’ve convinced everybody just yet — so let’s try and try this now. Blade size Ideally it's best to attempt to maintain this under three-inches, most US States and Cities have rules surrounding knives over 3.5 inches, so be sure to look that up on your space.

It has unfold like a virus throughout the trade. But if I have been a financial analyst I'd inform you that's solely his SECOND biggest invention. His real innovation is creating a market space where he can readily sell tons of of high end manufacturing knives that START at $350. The great thing about what Chris Reeve did is similar Www.Thebestpocketknifereviews.Com to what Starbucks did-he was in a position to convince consumers that there's worth in paying 300% more for one thing fairly primary. But in contrast to Starbucks, which makes dreadfully overroasted and overflavored espresso devoid of any subtlety, Chris Reeve used just about unmatched high quality and consistency to persuade customers. Holding a Sebenza.

You can purchase scale specific model trees, however they're very expensive when making an attempt to fill a big show with lifelike scenery components. Tree kits are rather less pricey and are useful for those with dexterity issues. If you are physically in a position, have a number of hours to spend and luxuriate in a hands-on approach - then making your own trees can be both fun and a money saving approach to deliver your mannequin railroad to life. Twigs and small branches which have broken from timber are likely to have more jagged ends than pine cones. When needed, use a pocket or utility knife to chop away any jagged ends.

Men have been carrying pocket knives for hundreds of years. But with elevated safety on the airport and different buildings, knives have been disappearing from males’s pockets. Yet these minor obstacles are not ample purpose to give up carrying a knife completely. The carrying of a pocket knife is a man Spyderco Bug Knife Review custom that should be continued. Why a Man Should Carry a Pocket Knife Jack knife. A jack knife has a easy hinge at one finish, and will have a couple of blade. The jack knife is in style among hunters, fishermen, and campers.

A camper trailer is a small, towable camper. It is normally pulled behind a car, much like a boat trailer. When in use, the camper is prolonged right into a full-dimension tent, which sometimes features a mattress and a table. Like traditional tents, a camper trailer requires regular maintenance. A gap custom knife makers in a camper trailer is simply as unpleasant as a gap in a conventional tent. A gap on the roof can expose you to outdoors insects and rain. To guard yourself from a disastrous tenting expertise, repair the hole on your camper trailer roof earlier than your subsequent journey.

Some individuals will notice that Nokia is constructing a special relationship with Microsoft, to the purpose where the manufacturer is ready to deliver extra exclusive options in its phones and push for issues to be added in later revisions. For those who're a WP fan, then there is perhaps an argument for committing to Nokia with a view to benefit from all those good issues to return. Nonetheless, we expect that is untimely. Drive is a pleasant exclusive feature, however there's not much else but. The Nokia-Microsoft relationship will definitely change into extra essential, but that's not sufficient to sway a buying resolution as we speak.

Due to right this moment’s know-how, even urban dwellers can carry around a small bit of survival tools. There are a number of very superb tools made which can be carried in a wallet or purse. These tolls are often referred to pocket survival instruments. Simply because you spend most of your time in the city, doesn’t mean you should be unprepared for emergency conditions. There may be all the time room in your purse or pockets for a pocket survival device of some kind. Loflin is charged with one depend of assault with a lethal weapon with intent to kill inflicting serious injury and one rely of misdemeanor assault on a handicapped individual.

To reattach the door slab, simply lift the door into the track whereas gripping it from the sides and lining up the pivot clips on the door slab to the pivot bolts on the wheeled monitor guides, clipping and then locking them in place. Now the door should swing freely back into place within the pocket. Modify the pivot bolts as wanted to make the door slab flush with the jamb. Reattach the door trim for a wonderfully gerber folding knives working pocket door. California over state lines may get you into trouble with federal legal guidelines or legal guidelines of other states. Native ordinances may additionally impact the legality of your knife.