However , immersed tunnels are generally build in soft soil shallowly and affected greatly by the earthquake . in view of its importance and underwater particularity , the destruction of immersed tunnels will be disastrous . accordingly , it is necessary to carry out earthquake - resistant research of immersed tunnels 然而，沉管隧道一般修建在软弱地层中，埋置浅，受地震影响大，同时由于沉管隧道的重要性及在水下的特殊性，一旦破坏将产生灾难性后果，因此，对沉管隧道进行抗震研究是十分必要的。
Due to the limited underwater action scope of a submarine , and it must be provided well maneuver performance , not only the depth - keeping and directional steady motion but also quick elusion or entering the battle status , which brings forward a high demand to submarine control 由于潜艇在水下的活动范围有限，同时潜艇又必须具备良好的操纵性能，既要保证定深，定向的稳定运动，又要能机动灵活的规避或进入武器发射的战斗状态。这样就给潜艇的操纵控制提出了很高的要求。
Bachu arch is a common forland uplift of southwest of tarim forland basin northeast of tarim forland basin . this arch previously is a low submerged paleohigh which rised integrality above water from late hercynian to terminal hercynian , was exposed to denudation mostly because of uplifting integrality in mesozoic , ulteriorly uplifted and strongly reformed in late himalayan . markit slope is a slope north dipping in early paleozoic , tilted in south - north orientation in hercynian 巴楚隆起作为塔西南前陆盆地和塔东北前陆盆地的共用前陆隆起，是一个早古生代潜伏于水下的低隆，海西晚期至末期呈整体性隆升，露出水面，中生代整体隆升，大面积遭受剥蚀；喜马拉雅晚期进一步隆升和强烈被改造，才定型成现今的构造格局。
These good qualities of spread spectrum technique also make it has good prosperity of application in underwater communication , such as identification between enemy ' s fleets and ours , distance measurement , navigation and orientation etc . this paper explores underwater spread spectrum communication primarily and realizes the underwater applications of doppler frequency search , channel hold , channel equalization and so on successfully 如潜艇通信、水下机器人遥控、测距、导航和定位等。本课题对水下扩频通信技术进行了初步的研究。成功实现了多谱勒频率搜索、信道跟踪和保持、多径分集等关键技术在水下的应用。
Researchers at the florida institute for human and machine cognition envision their work giving army rangers 360 - degree unobstructed vision at night and allowing navy seals to sense sonar in their heads while maintaining normal vision underwater - - turning sci - fi into reality 佛罗里达人与机械认知研究所的研究人员设想他们能够将科幻变为现实为陆军突击队员提供夜间360度全方位无阻碍的感知；使在水下的海豹特种部队用他们的脑袋来感觉到声波，同时不会丢失普通的感觉。
