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謝赫 國畫六法

 由畫家謝赫提出的「繪畫六法」為中國水墨畫訂下一些基礎理論: 一,氣韻,生動是也;二,骨法,用筆是也;三,應物,象形是也;四,隨類,賦彩是也;五,經營,位置是也;六,傳移,模寫是也
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Christmas cold brew coffee

Recipe ( 4 cups): Coffee with brew ratio of 1:5 , ie 158g coffee: 790g water(948 g total) Orange peels from 1 orange 1 cinnamon stick 4 cloves 1 star anise Optional: Grate some Nutmeg 3 or 4 Cardamon pods Put in fridge for 12 hours. After 12 hours, filter off with coffee filter paper, dilute with 1.5 x amount of water , or adjust with more water if you like. Enjoy !! Reference  Green vs black vs white Cardamom  

Universal color curve for roasted arabica coffee

Nature  scientific report July 2025 From UC Davies Conclusion To the best of our knowledge, this study is the first to systematically investigate the dynamics of coffee color during roasting using industry-standard roast profiles and various coffee origins on a commercial scale. Overall, our results demonstrate that changes in coffee color during roasting follow a consistent path in the CIELAB color space, which we define as “the universal roasted arabica coffee color curve.” standardize roast-level definitions:  Furthermore, regardless of the roast profile or origin, our coffees consistently exhibited approximately the same L*a*b* values at significant roast milestones such as color change, first crack, and second crack. Applications:  The universal roasted arabica coffee color curve provides a valuable quantitative  QC  standard for defining roast levels in the coffee industry.  Future work should explore a broader range of coffee species, origins, ...

虞喜對回歸年的推算及歲差

 晋代天文学家虞喜发现岁差,主要是通过冬至昏中星的对比得到的。依《 尧典 》所载 冬至昏中星 为昴星,而到了虞喜的时代,冬至昏中星为壁8度太强。这就是说,从帝尧至东晋这段时间内, 冬至昏中星 已从昴宿,经胃宿、娄宿、奎宿退行至壁宿8度多了,合计退行近51度。虞喜估计唐尧时代相距2700余年,由此而求得岁差的值为约53年西移1古度。祖冲之也提出“冬至所在,岁岁微差”的正确论断,他在刘宋大明年间制订的《大明历》中,定出冬至点45.9年西移1古度。它是中国第一部考虑了岁差的历法。祖冲之在历法计算中引进岁差,是在中国历法史上的一大贡献。在历法计算中,太阳方位是一个最为基本的数据。太阳位置的准确与否,直接关系到日月交会时刻和五星的出没方位等一系列问题;而岁差改正是正确计算太阳位置的重要环节。此外,《大明历》所采用的回归年长度为 365.2428 日,朔望月长度为 29.53059 日,两者都十分接近真值。但该历法当时未能颁用,直到近半世纪后才在梁朝颁用。 冬至昏中星:冬至那天黃昏时的南天中星 Weixin 長文版: 前言 漢朝初期時沿用古歷,以牽牛初度(冬至點離牛宿距星的赤道宿度不到一度(古1°相當於今0.986°))為冬至點。直到太初元年,漢武帝下令司馬遷等人編定太初歷時,根據實測,以牽牛星西方的斗宿中央附近建星為冬至點。 到元和年間,劉欽在重新編定太初歷時,比對前後曆法資料,因而發現到冬至點西移的現象。劉欽對此猶豫其詞,最後認為冬至點移動到牽牛星西方的斗宿的西側4度5分。但是思想保守的劉欽,在他重新編成的三統歷中,還是把牽牛初度時當作曆法的日月起算點。 東漢天文學家賈逵進一步測得冬至點既不在牽牛初度、也不在建星,而在斗宿21度的位置。不過,賈逵也只是想要對曆法上的錯誤進行修正,並未深究其中規律。 自此而後,中國古代天文學家對於冬至點西移的現象觀測亦多有所載,但皆是記而不論,不加多談/深究。 虞喜: 畢竟作為宣夜說的繼承者, 虞喜見此心有所感,把自己的觀察結合古人對於冬至點西移現象的紀錄分析中,得出太陽一周天(恆星年)不等於冬至一周歲(回歸年)的結論,即所謂的「天自為天,歲自為歲」。天上的星宿位置/坐標是固定,但太陽1年後(回歸年)的位置是獨自一位置/坐標 但若只是如此,顯然不足以讓虞喜成為歲差的發現者而留名 - 畢竟虞喜所述者都只是前人的記錄。所以, 虞喜更進一步...

2025冬至時間, 來自上海天文館的 微信

 有點貽笑大方 時間:12月21 23:02:48???(為何有超過15秒之差?) link 是因拷貝 Bmcx 的時間? Deepseek AI: 22/12 06:03 BJT??? 反觀 紫金山天文台:23:03 就無問題了 IMCCE: IMCCE seasons online   北京天文館 就給出的跟其他天文台同一時間 臺北天文館 HKAS 掩星組 fb

A320 recall

  Operators of some 6,000 Airbus A320-family aircraft scrambled over the weekend to undertake software modifications to mitigate the risk of uncommanded flight control inputs from what the manufacturer terms "intense" solar radiation. Airbus identified the issue during its probe into an Oct. 30 incident involving a JetBlue A320. The aircraft, en route to Newark from Cancun, suddenly lost altitude while in cruise. An A320 "recently experienced an uncommanded and limited pitch down event," EASA's EAD said, without identifying the specific flight. "The autopilot remained engaged throughout the event, with a brief and limited loss of altitude, and the rest of the flight was uneventful. Preliminary technical assessment done by Airbus identified a malfunction of the affected ELAC as a possible contributing factor." Twitter The aircraft had the newest ELAC software installed. Airbus determined reverting to the previous version eliminates the risk. https://avi...

Autumn nightsky on 8 nov 2025

 Cygnus