- published: 19 Sep 2012
- views: 3676
In physics, sound is a vibration that propagates as a typically audible mechanical wave of pressure and displacement, through a medium such as air or water. In physiology and psychology, sound is the reception of such waves and their perception by the brain.
Acoustics is the interdisciplinary science that deals with the study of mechanical waves in gases, liquids, and solids including vibration, sound, ultrasound, and infrasound. A scientist who works in the field of acoustics is an acoustician, while someone working in the field of acoustical engineering may be called an acoustical engineer. An audio engineer, on the other hand is concerned with the recording, manipulation, mixing, and reproduction of sound.
Applications of acoustics are found in almost all aspects of modern society, subdisciplines include aeroacoustics, audio signal processing, architectural acoustics, bioacoustics, electro-acoustics, environmental noise, musical acoustics, noise control, psychoacoustics, speech, ultrasound, underwater acoustics, and vibration.
The modern Olympic Games or Olympics (French: Jeux olympiques) are the leading international sporting event featuring summer and winter sports competitions in which thousands of athletes from around the world participate in a variety of competitions. The Olympic Games are considered to be the world's foremost sports competition with more than 200 nations participating. The Olympic Games are held every four years, with the Summer and Winter Games alternating by occurring every four years but two years apart.
Their creation was inspired by the ancient Olympic Games, which were held in Olympia, Greece, from the 8th century BC to the 4th century AD. Baron Pierre de Coubertin founded the International Olympic Committee (IOC) in 1894. The IOC is the governing body of the Olympic Movement, with the Olympic Charter defining its structure and authority.
The evolution of the Olympic Movement during the 20th and 21st centuries has resulted in several changes to the Olympic Games. Some of these adjustments include the creation of the Winter Olympic Games for ice and winter sports, the Paralympic Games for athletes with a disability, and the Youth Olympic Games for teenage athletes. The IOC has had to adapt to a variety of economic, political, and technological advancements. As a result, the Olympics has shifted away from pure amateurism, as envisioned by Coubertin, to allowing participation of professional athletes. The growing importance of mass media created the issue of corporate sponsorship and commercialization of the Games. World wars led to the cancellation of the 1916, 1940, and 1944 Games. Large boycotts during the Cold War limited participation in the 1980 and 1984 Games.
Unknown or The Unknown may refer to:
影片是強者我朋友的朋友在9月19晚間自家門口拍攝,使用器材是htc某型號錄製...! 以下是個小妹個人看法,如有誤解 請噓大力一點: ----------------------------- 首先我敢斷定這不是那種陽春led型風箏,led風箏在2009年由大陸某智者首創。曾經看過,相信估狗也goo的到。 片中高度粗估有兩三百公尺。從鏡頭及聲音判斷,影片提供者應該也zoom in到底了! (如真zoom in到底,那應該有700至1000公尺的高度..吧) 再來是它的彩光如呼吸般的閃爍。人工雖然也做的到。但是要做到忽大忽小又能不規則的變化,以現在led的光暈在那種距離是沒辦法達到。( LED只要在50公尺外,如有關鍵藍色led光,那我們就只能看到一團白光在那邊! 因為紅R藍B綠G=白色W) 距離限制考量和設備的重量是沒辦法達成影片中看到的現象及變化! 區區風箏也負荷不了那麼多led線材、電池、led燈...等重量 (聽強者說它已在定點停留有30分鐘之多)。 再來是影片中後段它開始出現紅色旋轉光圈。在有限的硬體上是不可能那麼自然達成。就算可以,沒人會想把那東西裝在風箏上,要嗎也是多加強飛行的特技設備。光成本和重量考量,這寧可用在遙控飛機或一般飛機等有價商品上。 雖然現已經有搖控風箏產品了,但光可搖控的距離和定點徘徊盤旋,就把當今的飛行玩具打趴在地了! 出去看了一下晚間風度大小,9月19雲林褒忠田洋沒風,小風也不足以讓風爭飛到離地仰角快90度又能定點盤旋。 如真在有風的狀態下,相信影片中的聲音會有很吵的風切聲,而不是強者的老木問偶兜賣是誰的講話聲 : ) 如我今天是操控風箏的那位蠢材,也不可能無聊到在定點玩了十分鐘以上,還不換位置飛行或電池續航力不足而慢慢降低高度,要嚇村民也不是這樣嚇的..! --不管你們信不信。小妹我是信了!!-- PS.以...