Chinese English

A relatively large area of free navigable water in an ice-encumbered SEA. In U.S. terminology, an area of SEA with less than one-tenth ICE CONCENTRATION.

A recording device designed to measure by revolutions of a small wheel, continuous linear di­stances on a MAP. Used in measuring the length of SHORELINE by closely following all the INDENTATIONS and sinuosities of the SHORE.

The situation of two periodic quantities differing by half a CYCLE. In ASTRONOMY, the situation of two CELESTIAL BODIES having either CELESTIAL LONGITUDES or sidereal HOUR ANGLES differing by 180°. The term is usually used only in relation to the position of a SUPERIOR PLANET or the MOON with reference to the SUN.

The point of intersection of lines which represent within the LENS those RAYS whose emer­gent directions are parallel to their respective inci­dent directions. This point lies on the optical axis.

A surface, usually of glass, ground and polished plane within a fraction of a WAVE LENGTH of light. An optical element or glass blank with an opti­cal flat is used to test the flatness of other surfa­ces.

A bottom sediment sampling device capable of obtaining as much as 1/2 cubic foot of sample from the ocean floor. Named for its likeness to an orange that has its peel quartered.

The path of a body or particle under the influ­ence of a gravitational or other force. For instance, the orbit of a CELESTIAL BODY is its path relative to another body around which it revol­ves. In water waves, the path of a water particle affected by the wave motion.

Member States promote economic growth, employ­ment, and improved standards of living for a sound and harmonious development of world economy.

The act of establishing the correct rela­tionship in direction with reference to the POINTS of the COMPASS. The state of being in correct relati­onship in direction with reference to the POINTS of the COMPASS. A MAP is in orientation when the map SYMBOLS are parallel with their corresponding ground features. A PHOTO­GRAPH is in orientation when it correctly pre­sents the perspective view of the ground or when IMAGES on the PHOTOGRAPH appear in the same direction from the point of observation as do the corresponding map sym­bols. See ORIENTATION OF PLANE TABLE, ORIENTATION OF SURVEYING INSTRUMENT, ORIENTATION: PHOTOGRAM­METRIC.

1.参照罗经点确定正确方向关系的行为，或处于此方向关系的状态。当地图符号与相应地物平行时，地图即完成定向。当像片能够正确显示地面的相应视图或像片上的图像如同相应的地图符号那样与在观测点上看到的方向相一致时，像片即完成了定向，参见orientation of plane table（平板仪定向），orientation of surveying instrument（测量仪器定向）， photogrammetric orientation（摄影测量定向）。 2. 在ECDIS中，指显示ECDIS信息的模式。典型模式有：“真北向上”-在航海图上，真北在显示信息的上方；“船首向上”-根据实际艏向显示（如船电罗经）；“航向向上”-根据行进的航向或航线显示。

In PHOTOGRAMMETRY, the scaling, levelling, and ORIENTATION to GROUND CONTROL (in a photo­grammetric instrument) of a relatively oriented stereo­scopic model or group of models.