标题： 昼长、一天及一年接收的能量随纬度、日期和倾角变化的计算 显示英文标题

标题： Computation of day length, amount of energy received over a day and over a year in function of latitude, date and obliquity

摘要： 在这些笔记中，我们计算了给予水平横截面（面积为1平方米）接收到的太阳能公式，该公式与纬度、地轴倾角和当前日期有关（这个量也与太阳通量成正比）。 我们还得到了一天内接收的能量公式、白天长度公式、根据纬度一年中某天是否可以观察到太阳到达天顶的可能性（在这种情况下，给出具体日期的公式）、观察极昼/极夜的可能性以及根据纬度这些现象开始的时间。 第1节介绍了4个不同的角度：地轴倾角、纬度、日期和时间，并引入了相应的旋转。 在第2部分，我们给出了太阳在天空中的位置。 这使得我们在第3部分能够计算白天的长度。以下各节除了第6节依赖于第5节外，都是彼此独立的。 在第4节，我们计算哪些纬度可以观测到极昼或极夜，并给出这些现象的开始和结束时间。 在第5节，我们从日出到日落对所接收的太阳能进行积分，从而得到一天内接收的能量总量。 在第6节，我们对全年接收的能量总量进行积分。 在第7节，我们证明只有位于热带之间的纬度可以观察到太阳直射，并给出一年中发生此现象的两个时刻。 在第8节，我们计算给定海拔和日期的日出和日落方向。 显示英文摘要

摘要： In these notes, we do the computation of the formula giving the expression of solar energy received by an horizontal section of 1 square meter, relatively to the latitude, obliquity and current day (the quantity is also proportional to the solar flux). We also obtain the formula of energy received during one day, of day length, of the possibility, according to the latitude, to observe the sun at zenith one day in year (and in this case, the formula of the day it happens), the possibility to observe a oplar night/day, and the time of beginning of these phenomenons according to the latitude. Section 1 introduce the 4 different angles which are obliquity, latitude, day and hour. We also introduce the corresponding rotations. In 2, we give the position of the sun in the sky. That make able to compute the day length in 3 Following sections are pairwise independent, except 6 which relies on 5. In 4, we compute for which latitudes it is possible to observe or not a polar day or a polar night, and give the time of beginning and end of these lasts. In 5, we integrate between sunrise and sunset the received solar power, which give us the quantity of energy received during one day. In 6, we integrate the following quantity in order to obtain the quantity of energy received per year. In 7, we prove that only latitudes located between tropics can observe sun at zenith, and give the two instants it happens in a year. In 8 we compute the direction of sunrise and sunset, given altitude and day.