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🌏 | Central Bank of Canada suggests early rate hike Economic growth is solid and quantitative easing ends


Central Bank of Canada suggests early rate hike Economic growth is solid and quantitative easing ends

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However, the supply bottleneck will be almost eliminated by the end of next year.

[Ottawa XNUMXth Reuters] – The Bank of Canada (Central Bank) is aiming to guide the overnight interest rate, which is the policy interest rate, on the XNUMXth ... → Continue reading


Wikipedia related words

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bottleneck(British: bottleneck) Is a concept of system design constraints. The English word for "bottle neck". In some areas (mainly in the chemical field)Rate-determining(Riso,((Used to indicate the element that "controls" "speed"), andbottleneck(Airo)There is also a consensus word.

80-20 principleAs shown by the above, when things do not proceed smoothly, the cause of the delay is a small part when viewed from the whole, and in many cases the situation does not improve no matter how much the other parts are improved.Such a factor part is called a bottleneck.

No matter how large the bottle is, the amount and speed of the contents flowing out (throughput) Is an association from being restricted only by the narrowed neck.

Various bottlenecks

Below are some examples of bottlenecks in various situations.

Information technology

  • Neumann's Bottleneck(Von Neumann Bottleneck).Neumann typeSee also
  • programmingIt is important to analyze the distribution of processing time, especially since bottlenecks can cause dramatic performance differences (such as XNUMX to XNUMX million times).Performance analysis).On the contrary, no matter how much you improve the part that is not the bottleneck, it will takecostThe improvement gained is small and the overall loss is (Amdahl's law.. This point is the same for other items). The ability to detect bottlenecks is an important quality as a designer.
  • networkRefers to a point where the communication bandwidth is narrow. One point on the networkPacket communicationIf is congested or slow, the network speed before or after it is fast or slowデータRegardless of the sparseness, the maximum communication speed is limited to the speed at one point where congestion is occurring.
    • On the communication pathswitch-routerThe network transfer performance of network devices such as these and the bandwidth of network lines become bottlenecks. Also, on a specific line or router on the routeconvergenceThe same applies when
    • Become the subject of communicationComputerInside in itselfbusTransfer performance,diskInput / output performance etc. may become a bottleneck[1]. (throughputreference)
    • protocolVarious controls (Packet communication, Error control, flow control, etc.) may become a bottleneck.
  • インターネットRefers to the same as above. The following are phenomena that are especially seen when using the Internet.
    • OnceTele HodaiIs a large scale in the heydayProviderIt happened a lot during tele-hodai time (digression: nowadays, the term bottleneck is almost unified, but some books when bottleneck became a problemBolt neckNotated as, of the screwboltWas used in the figure).
    • Broadband lineNowadays, the sameNetupperPrime timeAt (20:24 to XNUMX:XNUMX), not only the congestion of the entire network, but alsoWeb serverEtc. load increase,throughputIt is the main bottleneck above.
    • WidespreadFiber optic internet connectionInWANとLANThere is no big difference in speed withPCThere is also a phenomenon that the network transfer performance of is a bottleneck in the speed test.

Economy / Management

Traffic and rivers

River,道路Etc. refers to the part that obstructs the flow rate. Specifically, intersections with relatively long red light times and reduced width ・LaneDue to the decreaseTraffic jamThis is the place where the river cross section is narrow and a sufficient amount of water cannot flow down.TrainThen most ofDouble trackOnly a small part of the routeSingle lineThe number of trains is limited on the track, such as the section whereTransport obstacleIt refers to a place where it is difficult to respond to time.

In addition,Ministry of Land, Infrastructure, Transport and TourismThen in the cityRailroad crossingAbout, among the places that hinder road traffic due to the large number of trains, railroad crossings with long cutoff times are called "Railroad crossing without openingOn the other hand, railroad crossings with a large amount of traffic interruption (traffic volume x interruption time) are called "bottleneck railroad crossings".[2].

PedestrianAt the entrance and exit in trafficStairsEtc. become a bottleneck.Crowd accidentIf congestion is expected, appropriate passage design and guidance are required in advance.


Genetic bottleneckIeGenetic diversityRapid decrease. This is because the principle is the same as when a small number of things are taken out from the neck of a narrow bottle.


rifle,HandgunMade of metal used forcartridgeThe diameter of the cartridge case itself is smaller than the diameter of the cartridge case itself.warheadIn some cases, the diameter of the cartridge case is narrowed down according to the size of the warhead, and this cartridge case is called a bottleneck.With such a structure, the amount of charge can be increased as compared with the case of using a cartridge case having the same diameter as the warhead, so that the propulsive force of the warhead is increased and the initial velocity is increased, so that the power and the flight distance can be extended.However, in the case of a firearm that uses a cartridge with a bottleneck, the chamber needs to be precisely processed to match the bottleneck of the cartridge case, and a strong closing mechanism is required to increase the firing pressure. If you want to miniaturize the firearm inrevolver,Straight blowbackIf you want to make the structure as simple as possible, the bottleneck is often not used.


Physical chemistryInReaction kineticsso,Rate-determining stepAndChemical reactionIt is the slowest reaction in the mechanism and governs the rate of all reactions that result in the production of products.[3].


[How to use footnotes]
  1. ^ "Will SSDs make games faster? Corsair SSD "Force Series" had the answer”. 4Gamer.net (December 2010, 5). NovemberBrowse.
  2. ^ Elimination of railroad crossings that do not open 2. Railroad crossing traffic condition overhaul Ministry of Land, Infrastructure, Transport and Tourism
  3. ^ AG Whittaker; AR Mount; MR Heal; Translated by Wataru Nakamura "Keynote Chemistry Series Physics Chemistry Keynote" Springer Fairlark Tokyo, 2002.ISBN 4-431-70956-8. 

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