篇章結構解析: 62. Yet, the gabelle, and the “bread question” remained among the most unsettling social and political issues throughout the Revolutionary and Napoleonic periods (1789-1815) and well beyond.
閱讀測驗解析: 63. Born in 1785 in southwestern Germany, Baron Karl Drais was one of the most creative German inventors of the 19th century.
閱讀測驗解析: 64. The baron’s numerous inventions include, among others, the earliest typewriter, the meat grinder, a device to record piano music on paper, and two four-wheeled human-powered vehicles.
閱讀測驗解析: 65. But it was the running machine, the modern ancestor of the bicycle, that made him famous.
閱讀測驗解析: 66. The running machine, also called Draisine or hobby horse, was in effect a very primitive bicycle: it had no chains and was propelled by riders pushing off the ground with their feet.
閱讀測驗解析: 67. Though not a bike in the modern sense of the word, Drais’ invention marked the big bang for the bicycle’s development.
閱讀測驗解析: 69. The frame and wheels were made of wood; the steering already resembled a modern handlebar.
閱讀測驗解析: 70. Drais’ big democratic idea behind his invention was to find a muscle-powered replacement for the horses, which were expensive and consumed lots of food even when not in use.
閱讀測驗解析: 71. The machine, he believed, would allow large numbers of people faster movement than walking or riding in a coach.
閱讀測驗解析: 72. Drais undertook his first documented ride on June 12, 1817, covering a distance of 13 kilometers in one hour.
閱讀測驗解析: 73. A few months later, Drais created a huge sensation when he rode 60 kilometers in four hours.
閱讀測驗解析: 74. These were later followed by a marketing trip to Paris, where the hobby horse quickly caught on.
閱讀測驗解析: 79. There were frequent collisions with unsuspecting pedestrians, and after a few years Drais’ invention was banned in many European and American cities.
閱讀測驗解析: 81. Decades later, the machine was equipped by Frenchmen Pierre Lallement and Pierre Michaux with pedals to become the modern bicycle.
題組解析: 83. But if the flickering happens millions of times a second—far faster than the eye can see or the brain process—then it might be harnessed to do something useful, like transmitting data.
題組解析: 84+85. This is the idea behind Li-Fi, or Light Fidelity. 85. The term Li-Fi was coined by University of Edinburgh Professor Harald Haas in a 2011 TED Talk, where he introduced the idea of “wireless data from every light.”
題組解析: 86. Today, Li-Fi has developed into a wireless technology that allows data to be sent at high speeds, working with light-emitting diodes (LEDs), an increasingly popular way to illuminate public areas and homes.
題組解析: 87. Using LED lights as networking devices for data transmission, Li-Fi has several advantages over Wi-Fi (Wireless Fidelity).
題組解析: 88. First, Li-Fi allows for greater security on local networks, as light cannot penetrate walls or doors, unlike radio waves used in Wi-Fi.
題組解析: 89. As long as transparent materials like glass windows are covered, access to a Li-Fi channel is limited to devices inside the room, ensuring that signals cannot be hacked from remote locations.
題組解析: 90. Also, Li-Fi can operate in electromagnetic sensitive areas such as aircraft cabins, hospitals, and nuclear power plants, for light does not interfere with radio signals.
