Portal field news

Portal field news

in ,

🚗 | If the time alignment setting goes well, the “amount of information” will increase [sound tuning]

Photo An example of an audio car equipped with a main unit equipped with a "time alignment function" (production shop: K Sound <Hiroshima Prefecture>).

If the time alignment setting goes well, the amount of information increases [Sound Tuning]

If you write the contents roughly
Repeat the fine adjustment, being careful not to change the height.

In car audio, the "sound tuning function" demonstrates its power.In this series, I will try to do that operation myself... → Continue reading


Wikipedia related words

If there is no explanation, there is no corresponding item on Wikipedia.

高 さ

高 さ(Takasa) is垂直DirectionalLengthThat is.重力In the working environment, it refers to the length in the direction of gravity.Also, spatialPhysical quantityBesides the height astemperature-ratio·frequency·PriceIt is common to express such things as "height".

That the height is largehigh, The height is smallLowSay.

Physical height


For height weighing, usually the same as lengthunitIs used.International unit system In (SI)Mm,Centimeter,Meters,KilometersEtc.

Metric system, the geographical height is expressed in meters.Although there is no clear distinction, heights above about 10 kilometers are expressed in kilometers.As with distance, do not use units larger than megameters.Shakunuki methodThen, in the unit of height, no matter how large the value isShakuThe following units are used.for exampleJapan AlpsThe height of is said to be "XNUMX shaku".Imperial systemThen the height is exclusivelyフ ィ ー トIs used,YardIs rarely used.


The height in geographyAverage sea levelIs the height fromelevation(Hyokou) is often used.If you take any two points, the difference in elevation between the two pointsRatioIt's called (flying).Regional geographyThen.[Question]For the summit of a mountain or hill, the relative height from the lowest contour line that does not include points higher than the summit among the contour lines surrounding the summit.prominenceThat.

In Japan, except for elevations on remote islands far from the mainlandTokyo BayThe average sea level of "Tokyo Bay average sea level (TP) ”is the standard for altitude.ActualSurveyingAs a reference point forChief of Staff OfLand Survey DepartmentIs on the site whereDiet Front ParkWas installed inJapan's Geodetic OriginIs used.

Incidentally,Above sea level(Kaibatsu) is also an expression that expresses height, and is generally used in the same way as "elevation", but it is not near Tokyo Bay but near.PortBased on the average sea level such as[1][2].(I.e.MeasuresLowlandMeasures,climaxSince it is more important to compare with the neighboring sea level than Tokyo Bay for countermeasures, the signboards above sea level and ""Zero meters above sea levelIt is common to use "above sea level" in words such as "."

地球Since there is no sea level in other celestial bodies, an appropriate reference plane to be used instead of the sea level is defined for each celestial body.

On a planeMapThen.contourOften represents altitude.Geographic information systemThen,Digital elevation modelDiscrete elevation values ​​by (DEM) are often used.

In 2018, the government decided to change from the manual leveling survey that had been continued for 135 years to the satellite survey that can obtain data faster by using artificial satellites etc. Announced that data is expected to be generally available in 6 years[3].

Water depth

The length from the average water surface to a certain position in the water,depth(Depth)·depth(Shindo) ・Water depthIt's called (Suishin).In the case of the sea, it is a value obtained by taking a minus from the altitude of the seabed.(I.e.,riverIn the case of, the water depth is calculated from the altitude of the average lake surface.If you pullIt becomes the altitude of the bottom of the water.Alternatively, subtract the bottom elevation from the average lake elevation to get the water depth.

The depth of the coast and lakesIsolinesIt is represented by.

Water level

Tide ebb and flow-climax-(I.e.-洪水-DroughtWhen paying attention to the height of the water surface (or sea level), such as, the height of the water surfaceWater levelIt's called (Sui).When expressing the water levelelevationIt may be expressed by the height measured from an arbitrary reference height peculiar to the area without using.The water level at which the river is in danger of overflowing the embankmentDangerous water levelThat.

Not just the surface of the water (or the surface of the sea)ポ ッ ト,boilerIt may also be used for the water surface in a container such as.

Ground height

The vertical distance from the ground surface to the measurement point of an object existing on the groundGround heightIt's called (Chijokou).OutdoorSignboardAnd wirelessantennaOften used for heights such as, this isInstallation ground clearanceAlso known as (Sekchijokou).For an antenna, it is the vertical distance from the ground to the feeding point.

In general, the term ground clearance is often used for the maximum height above the ground.The ground clearance in a building is the vertical distance from the lowest ground level that the building touches to the highest point of the building.The same applies to the ground clearance of standing trees.

Minimum ground clearance

Minimum ground clearanceWhat is (Saiichijokou)?AutomobileIn term, it refers to the vertical distance from the horizontal ground surface to the lowest point of the car body.

Standard ground clearance

With ladderFire truck OfStandard ground clearanceIn summary, (Kikuchijokou) is in a no-load state.LadderThe vertical distance from the ground surface to the center of the cross rail at the top of the ladder or the support pin of the basket when the ladder is upright and extended to the maximum.Ladder vehicles are classified according to this standard ground clearance, and when a fire engine procures a fire engine.Ministry of Internal Affairs and Communications Fire AgencyThe standard amount of national subsidy will be decided.


When referring to the height of a measurement point in the air, "height"(Altitude) is often used.For this reasonaircraft"Altitude" is also used for the height at which the aircraft flies.Usually, the height from the sea level at that point, that is, "Above sea levelIs displayed.The altitude measured from the ground surface, not from the sea surface, is called "ground altitude".


The height of a two-dimensional figure is one side底 辺Including the bottomStraight lineTo the point on the farthest figure距離.

For example,triangleIn the case of, for the base of any one selected, the third that does not belong to itvertexDropped from to the bottomPerpendicular lineThe length of is the height.Trapezoid(parallelogramIn the case of), one of the set of parallel sides is the base, and the distance between the two parallel sides is the height.

Similarly, in the case of a three-dimensional figure, when one side is the bottom surface, the bottom surface is included.flatThe distance from the farthest point on the figure is the height.cone-pyramidThen, it is the length of the perpendicular line drawn from the apex to the bottom.Frustum / Pyramid FrustumThen, it is the distance between two parallel planes.


[How to use footnotes]
  1. ^ Ministry of Land, Infrastructure, Transport and Tourism e-mail magazine dated August 25, 8 "Do you know the origin of Japanese standards?"
  2. ^ Geospatial Information Authority of Japan Q & A "What is the difference between altitude and sea level?"
  3. ^ How to determine the altitude will changeNHK, September 2018, 3

Related item

外部 リンク


Back to Top