I live in the land of Disney, Hollywood. You may think people in such an attractive and exciting, fun-filled place are happier than others. If so, you have some mistaken ideas about the nature of happiness.

    Many intelligent people still consider happiness equal to fun. The truth is that fun and happiness have little or nothing in common. Fun is what we experience during an act. Happiness is what we experience after an act. It is a deeper, more lasting emotion.

    Going to an amusement park or ball game, watching a movie or television, are fun activities that help us relax, temporarily forget our problems and maybe even laugh. But they do not bring happiness, because their positive effects end when the fun ends.

    I have often thought that if Hollywood stars have a role to play, it is to teach us that happiness has nothing to do with fun. These rich, beautiful people have constant access to glamorous parties, fancy cars, expensive homes, everything that brings “happiness”. But in memoir after memoir, famous people expose the unhappiness hidden beneath all their fun — depression, alcoholism, drug addiction, broken marriages, troubled children and extreme loneliness.

    Ask an unmarried man why he refuses to get married even though he finds dating to be less and less satisfying. If he's honest, he will tell you that he is afraid of making a commitment. For commitment is in fact quite painful. The single life is filled with fun, adventure and excitement. Marriage has such moments, but they are not its most distinguishing features.

    Similarly, couples that choose not to have children are deciding in favor of painless fun over painful happiness. They can dine out whenever they want and sleep as late as they want. Couples with babies are lucky to get a whole night's sleep or a three-day vacation. I don't know any parent who would choose the word fun to describe raising children.

    The way people stick to the belief that a fun-filled, pain-free life equals happiness actually reduces their chances of ever achieving real happiness. If fun and pleasure are equal to happiness, then pain must be equal to unhappiness. As a result, they fear the pain unavoidably brought by such things as marriage, raising children, professional achievement, religious commitment and self-improvement.

    But, in fact, the opposite is true. More times than not, things that lead to happiness involve some pain. The very efforts are the source of true happiness. Understanding and accepting that true happiness has nothing to do with fun is one of the most liberating realizations we can ever come to.

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    Enough sleep is important to health. The amount of sleep needed depends on the age of the person and the conditions in which sleep takes place. The young may need more sleep than the old, but usually eight hours are enough for the health of grown-ups. Some can do with less than this amount, but others may need more. Every person knows his own need. It is then a matter of good judgement to satisfy his need. Sleep should always be enough to make one bring back his strength and get ready for a day's work.

    Fresh air is necessary to sound sleep. It is not without reason for some people to think that it is practicable to sleep in the open air. When one can keep himself warm, out-of-door sleeping probably gives the body its most complete relaxation (放松).

    Ability (能力) to sleep lies largely in habit. The conditions referred to only lead to sleep. Out-of-door exercises, a good habit of regular hours and the avoidance (避免) of late eating and worry, which are largely within the control of any person, are all helpful to sound sleep.

    A bath at bedtime, neither hot nor cool but of body temperature may be helpful to sleep. Sleep-producing drug (药) should never be taken except when suggested by a doctor.

    Many years ago, people relied on the sun, the moon and stars to find their way around. Later, the compass was introduced. And now, we have satnav（卫星导航）systems to guide us. A satnav system uses groups of satellites to show the user's location. They send information to a receiver, such as a smart phone, to show us where we are.

    The earliest built satnav system is the Global Positioning System, which belongs to the US. Then there is Russia's Global Navigation（导航）Satellite System, the European Union's Galileo and China's own satellite navigation system, BeiDou.

    On October 14, 2017, an ARJ21-700 plane, which was the first domestically-produced jet equipped with the BeiDou navigation system, successfully completed a test flight. The results showed the performance of the system developed by China matches that of similar systems produced abroad, according to the Commercial Aircraft Corporation of China.

    Since its introduction in 2000, the Beidou navigation system has seen increasing numbers of applications linked to everyday life, from shared bikes to farming.

    When it comes to shared bikes, smart locks that support BeiDou chips offer more accurate positioning than others, making it easier to find a bike.

    Farmers can use BeiDou-enabled tractors to plow（犁）the soil and use unmanned aircraft with BeiDou to sow seeds, which can improve efficiency and make better use of resources. BeiDou's farming applications have spread from Heilongjiang province to Beijing, Liaoning, Shanxi, Hubei and other regions across China.

    With its many uses, the Beidou navigation system is even playing a big role in the Belt and Road Initiative（— 带—路）. “To date, the BeiDou system has covered most parts of the Asia-Pacific region, as well as counties along the Silk Road Economic Belt and the 21^st Century Maritime Silk Road” said Yang Changfeng, Chief designer of the BeiDou system.

    Today, there are more than 20 BeiDou satellites above our heads, and China plans to launch even more this year to expand the BeiDou network to better serve the Belt and Road Initiative.

    “As BeiDou expands its overseas reach, it will be increasingly popular in the logistics （物流）industry,” said Miao Qianjun, secretary-general of the navigation services association. “Ships, for example, can use it to position themselves while sailing across oceans to European countries, no longer limited to Southeast Asian regions in the near future.”

    The weather is very important to farmers. The calendar might say “August”， but the weather's more like October. For some farmers the cool weather is a good thing. For others, it's a cause for concern.

    At Apple Hill, the cooler weather was giving the Boeger Winery a chance to concentrate on bottling instead of picking. “Things were really maturing, it has just been a welcome relief to have more time to prepare.” said Greg Boeger of Boeger Winery.

    But down in the Delta, the earlier hot weather has them two weeks ahead of schedule. Their harvest actually started on Tuesday, and this cooling trend is a worry. There have been no problems yet, but for each of the last two years heavy rain right after Labor Day was a problem, one that Don Pylman would not like to see repeated.

    “If it doesn't start raining, we're in good shape，” said Pylman. “If the sun comes out and clears up we can get right back to work, but if we do get rain, the rots will start.”

    The kind of grape makes a difference as well. Thin­skinned grapes like the chardonnay variety are much more sensitive to rain than some of the others. They're also more difficult to dry off.

    Developed by researchers and designers specializing in typography(印刷术)and behavioral science, Sans Forgetica is a new font(字体)designed to help readers better remember the information they read by forcing them to spend a bit more time on each word.

    The design of Sans Forgetica is based on a font called Albion, but with substantial  modifications(修改)to reduce familiarity and attain its goal of engaging the brain more and helping the reader retain(保留) more information. It was developed by scientists at RMIT University in Melbourne, Australia, who believe it could help students studying for exams.

    “We believe this is the first time that specific principles of design theory have been combined with specific principles of psychology theory in order to create a font, ”Behavioral economist Jo Peryman told DW.

    If fonts are too familiar, readers often glance over them without their brain creating may  memories of what was read. At the same time, if a font is too outlandish, the brain has to struggle too much to decipher(破译)it while neglecting the retention of information. According to its developers, “Sans Forgetica lies at a sweet spot where just enough obstacle has been added to create that memory retention.” Its modifications force readers to spend more time, but not too much time, reading each word, allowing the brain to engage in deeper cognitive processing.

    So does Sans Forgetica actually work? Does it help readers better remember the information they read? So far, studies have shown that it can make a difference, although not a significant one.

    One experiment had 96 participants recall word pairs presented in three different fonts. They remembered 69 percent of the word pairs written in Sans Forgetica, compared to 61 percent for the other fonts. In a different experiment, 303 students took a mock(模拟)multiple-choice exam, and whenever the text was presented in Sans Forgetica, they remembered 57 percent of the text, compared to only 50 percent of the surrounding text written in Arial font.

    So Sans Forgetica won't give you the memory of an elephant, but if you're the kind of person who believes every little bit helps, it might be worth a try.

    The big fire in April that tore through the Notre Dame Cathedral in Paris(巴黎圣母院) is still fresh in people's minds. The 800-year-old landmark suffered great damage to its top, but thankfully the most valuable religious relics and cultural treasures were undamaged.

    So a US publishing company GoArchitect organized the People's Design Competition to invite designers, worldwide to share their ideas of rebuilding the French landmark. The open call attracted more than 200 proposals from 56 countries and regions. In the end, Chinese architects Cai Zeyu and Li Sibei won the competition with their striking design. They are both the post-90s generation.

    Named "Paris Heartbeat", the design replaces the old top with a kaleidoscope(万花筒) of multifaceted mirrors, which is combined with a mirror roof, reflecting the ever–changing urban environment.

    The kaleidoscope is the floating "time capsule", at the top using magnetic levitation(磁悬浮) technology, which is meant to open every half century. The "time capsule" moves up and down, breathing and beating together with the city.

    "I believe that the 'time capsule' can be achieved with present technology," Cai told the Global Times.

    The pair hoped that their design, Paris Heartbeat, could meet people's high expectations for the rebuilding. As Cai and Li told GoArchitect, "Notre Dame witnessed Parisian history. It burns, survives and co-breathes with the ever-changing world…The 2019 fire will mark a new era."

    Though people still don't know what kind of design the French government will choose, it's clear that people around the world hope that the lost beauty of Notre Dame will come back. Once rebuilt, it will certainly become a permanent part of history and the Parisian skyline again.