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發現隔壁備用鑰匙藏在這 裝潢工7度大搖大擺行竊 Horrn Antenna
視覺是最寶貴的感覺。科學家可能找到視網膜再生的關鍵。(圖/Shutterstock、達志)
來自: https://www.chinatimes.com/realtimenews/20250424005531-260408
The Log Periodic Antenna as known as LPDA is a wideband directional antenna that provides gain and directivity combined over a wide band of frequencies.
Both Log-Periodic Antennas and Yagi antennas are high gain directional antennas. The main difference between these antennas is that Log-Periodic Antennas support wider frequency bandwidths and are physically much larger than Yagi antennas.
The log-periodic dipole array typical VSWR is 2:1 and operates over a much wider bandwidth and will have a lower gain for an equivalent number of elements.
With this level of performance, it is ideal for many applications, although a log-periodic antenna will be much larger than a Yagi of an equivalent gain.
Log Periodic Antenna (LPDA) Log Periodic Antenna (LPDA) Log Periodic Antenna (LPDA) Log Periodic Antenna (LPDA) Log Periodic Antenna (LPDA)
恢復視力不是夢：科學家成功逆轉視網膜損傷
韓國的醫學團隊，發現了與視網膜再生有關的關鍵蛋白質分子，利用這個發現，他們正在開發視網膜重建的相關藥物，有可能在未來幾年，使許多視覺衰退的病患重見光明。
視覺是人類最重要的感覺之一，然而也非常脆弱。眼睛的構造極為精密，雖然我們已能更換角膜與水晶體，但是我們對於最精密的視網膜，仍然不甚瞭解。更麻煩的是，哺乳動物的視網膜系統難以再生，一但功能衰退就不會恢復。全球有超過 3 億人因各種視網膜疾病，面臨失去視覺的風險，儘管一些治療有助於減緩過程，但是到目前為止，還沒有有效的療法，可以恢復已經喪失的視力。
所幸希望就在不遠處。韓國科學技術研究院的研究人員，研發出一種可成功恢復視力的新藥。3月30日，韓國科學技術研究院宣布，由生物科學係金鎮宇教授領導的研究團隊，研發了一種透過再生視網膜神經，來恢復視力的治療方法。
來自: https://www.chinatimes.com/realtimenews/20250424005531-260408
The Log Periodic Antenna as known as LPDA is a wideband directional antenna that provides gain and directivity combined over a wide band of frequencies.
Both Log-Periodic Antennas and Yagi antennas are high gain directional antennas. The main difference between these antennas is that Log-Periodic Antennas support wider frequency bandwidths and are physically much larger than Yagi antennas.
The log-periodic dipole array typical VSWR is 2:1 and operates over a much wider bandwidth and will have a lower gain for an equivalent number of elements.
With this level of performance, it is ideal for many applications, although a log-periodic antenna will be much larger than a Yagi of an equivalent gain.
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