m******g 发帖数: 621 | 1 这个BILL GERTZ是么背景,跟DOD关系紧密,每次这种消息都是他先传出来的。NB
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http://freebeacon.com/national-security/china-conducts-third-fl
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China conducted the third flight test of a new hypersonic missile this week
as part of its strategic nuclear program and efforts to develop delivery
vehicles capable of defeating U.S. countermeasures, defense officials said.
The flight test of the developmental Wu-14 hypersonic glide vehicle was
monitored... 阅读全帖 |
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a*******a 发帖数: 451 | 2
应该是直译,搜到链接这里
http://www.awaker.hk/trantasks/about-the-horse-boat-mh370-inter
WHAT HAPPENED TO MALAYSIAN AIRLINE FLIGHT 370?
before the airliner went missing. In this test that was to show the Western
powers the magnitude of this new weapon, this Topol Missile, a missile was
fired at a target ship in the Pacific Ocean.
The location is not seen as clearly, but a message had been sent to the
Western military powers that this would occur, and the Western military
powers did observe the test and the... 阅读全帖 |
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d*******3 发帖数: 8598 | 3 【 以下文字转载自 Physics 讨论区 】
发信人: Jerry0803 (Jerry and Tom), 信区: Physics
标 题: 【转载】漫谈物理学的过去、现在与未来 冯端
发信站: BBS 未名空间站 (Sat May 10 22:33:04 2014, 美东)
漫谈物理学的过去、现在与未来*
冯 端
摘 要 文章试图对物理学的发展历史作一透视,从而理解其现状,并进而窥测其未
来的前景.我们希望这一看法对于当今从事物理学教学与科研的人士有所助益.由于物理
世界的层次化,诸层次之间既可能存在耦合,又可能出现脱耦.因而大量粒子所构成的
复杂体系中所涌现的各种层展性质就不能简单地还原成个别粒子所服从的规律.我们根
据这一观点并结合物理学的未来前景,讨论了当今物理学研究的若干前沿问题.一切迹
象预示着物理学将有光明的前景.
关键词 物理学,历史,现状,前景,前沿,物理世界的层次化,层展性质
RAMBLING ABOUT THE PAST,PRESENT AND FUTURE OF PHYSICS
Feng Duan
(Department of Physics,Naj... 阅读全帖 |
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C****2 发帖数: 2904 | 4 你这是在黑TG吗?20 mach也忒快了,10马赫好不好。 |
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C****2 发帖数: 2904 | 5 你这是在黑TG吗?20 mach也忒快了,10马赫好不好。 |
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G*****n 发帖数: 3863 | 6 Mach 1.2十分钟,都可以跑250公里了。AIM120D的射程也才180公里。
等敌方机动躲过F-35的导弹,F-35早就跑掉了。 |
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c***c 发帖数: 21374 | 7 神父专家系统
这个是NPL和maching learning的范畴了 |
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n*******4 发帖数: 2285 | 10 查MARV:
The Pershing II's RV weighed 1,400 lb (640 kg) and traveled at Mach 8. It
was fitted with four control fins to perform a 25-G pull-up after reentering
the atmosphere, then glided 30 nmi (35 mi; 56 km) to the target and pitched
into a terminal dive.
RV |
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a******9 发帖数: 20431 | 11 有毛可生畏的 锁男整天一惊一乍
maching learning和各种基于regression的算法本来就是设计出来做这些事的 无非就
是用机器运算力替代纯计算的脑力 |
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n*******4 发帖数: 2285 | 12 说东风有误差也是误差几百米那种。可你根本无法预测哪颗能中,哪颗不能中, 都得
发SM拦截,不然就来不及了,df-21九分钟就飞抵目标,SM3反应时间只有2-3分钟, 因
为它自己加速,飞到大气层外需要时间。
看看wiki上的评价,估计SM3,SM6,SM2拦截东风单发成功率远低于50%!能到10%就不错
。即便50%, 也要7颗拦截弹才能达到99%拦截成功概率。
https://en.wikipedia.org/wiki/DF-21
United States Naval Institute in 2009 stated that such a warhead would be
large enough to destroy an aircraft carrier in one hit and that there was "
currently ... no defense against it" if it worked as theorized. The United
States Navy has responded by switching its focus from a ... 阅读全帖 |
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h*h 发帖数: 27852 | 13 【 以下文字转载自 Physics 讨论区 】
发信人: zero7 (007), 信区: Physics
标 题: 爱因斯坦奇迹年探源
发信站: BBS 未名空间站 (Sat May 28 21:52:22 2016, 美东)
爱因斯坦奇迹年探源
摘要: 爱因斯坦于1905年取得4项历史性成就是奇迹;更奇的是,他完全是用业余时间
来探索科学的。本文着重从其成长过程和历史背景来分析产生奇迹的源泉。爱因斯坦的
非凡创造力,不仅来自他对自然奥秘的惊奇和敢于向传统与权威挑战的反叛精神,更来
自他那深邃的哲学思考——来源于理性论哲学家斯宾诺莎的自然界统一性的信念,以及
来源于经验论哲学家休谟和马赫的怀疑精神和独立批判精神。文章随后简要介绍了爱因
斯坦在第二个高峰期(1915—1917)所取得的伟大成就,并认为他一生中至少有8项成
就可以获得诺贝尔奖。文章最后着力展示了爱因斯坦的人格魅力——强烈的社会正义感
和社会责任感,为和平、自由、民主和人权的理想所作的不懈努力,以及对中国人民苦
难的深切同情。
关键词: 爱因斯坦 奇迹年 双重奇迹 两个高峰期 独立批判精神 自然界统一性 人格魅力
一 双... 阅读全帖 |
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G*******n 发帖数: 6889 | 14 该“误射”的一大疑点是误击渔船,受水下300-400米发射弹道导弹毒害的军盲们辛亏
还知道这说明该飞弹是掠海飞行的,但却不能从这个线索加深分析:一般超音速SSM(
反舰导弹)为了达到超音速(>=Mach 2.0, 不包括像YJ-83这种勉强超音速的“争气
弹”)多在中高空巡航,以保证冲压发动机的充分进气,最后主动雷达开机阶段再掠海
或俯冲攻击,这样航程也打,缺点是在巡航段容易被敌舰雷达很远就探测到,典型如“
现代”级上的3M80(SS-N-22),雄风三比较特别的是它有一巡航段也掠海的模式,
这样突防性增大,缺点是射程从中高空巡航模式的300-400公里减少到120-150公里,这
次掠海时,误击渔船,说明目标在120-150公里以内,只需用圆规在海图上一划,就看
找出实际的固定或机动目标,而不用更多猜测是不是“误射” |
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y***k 发帖数: 9459 | 15 不是末端,是全程。看视频,轰六巡航速度.85 mach,导弹在一秒内加速到的速度至少
三倍于轰六当时的速度。 |
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d*b 发帖数: 4453 | 16 中国最近的机场到黄岩岛的距离差不多要1000公里。除了这轰炸机可以去转一圈还能回
来外,战斗机飞去就回不来了。 这没有战斗机护航的轰炸机,胆大不知羞的只身跑那
里去除了照张照片忽悠一下老百姓外,不就是去送死嘛?
说实话,这东西跑过去了,别说用弹弓打,弄不好用竹竿都能捅下来!
外交搞不过,打仗又打不过,战斗机飞不到,就用轰炸机巡航忽悠老百姓,笑死人了。
以下是轰6基本信息
最高速度:1,050 km/h (567 knots, 656 mph)
巡航速度:Mach 0.75(768 km/h, 477 mph)
战斗半径:1,800 km(970 nm, 1,100 mi)
航程:6,000 km(3,200 nm, 3,700 mi)
实用升限:12,800 m(42,000 ft)
翼负荷:460 kg/m²(94 lb/ft²)
推重比:0.24 |
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t**8 发帖数: 4527 | 17 杨28 唯一排上名的是活着的有名物理学家19 , 在李政道之后,
其他的连前 50 名都排不上
Greatest physicist everThis is a featured page
In intellectual rankings, greatest physicist ever is an epitaph given to a
person, depending on ranking methodology, some rankings of which are listed
below, that classify, list, or describe someone as being the greatest
thinker in the field of physics of all time.
One of the more dominant surveys was the recent millennium poll on the
greatest physicist of all time, conducted by the British journal Phy... 阅读全帖 |
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b**********r 发帖数: 2530 | 23
穷玩车富玩表是国内刚开放时被冲击浑了。概念错误。
有4000万美元的车,没有800万美元的表 |
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b**********r 发帖数: 2530 | 24 标题里的几种车型和年份,是泡中高端白妞必备,锁男们拿笔写下来,烂熟于心 |
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发帖数: 1 | 25 高速火车是不可能实现的,因为高速下人将无法呼吸,乘客会因窒息而死。——某Phd"
Rail travel at high speed is not possible because passengers, unable to
breathe, would die of asphyxia." -- Dr. Dionysus Lardner, 1793-1859
钻油?用
钻头能钻出石油?你脑子进水了么?——1859年德雷克要勘探石油时候的反对者"Drill
for oil? You mean drill into the ground to try and find oil? You're crazy."
-- Workers whom Edwin L. Drake tried to enlist to his project to drill for
oil in 1859.
汽车已经没什么可发展的了。这些年内燃机的原理就没有什么改进么。—
—美国科学杂志,1909"That the automobile has reached the limit of its
developmen... 阅读全帖 |
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a****2 发帖数: 3735 | 26 飞机上所用的常用速度有4种:指示空速(IAS),真空速(TAS),地速(GS),马赫数(Mach).
指示空速:飞机和空气相对的速度,也是空速表上显示的速度,有时简称为"表速""空速".
真空速:经气压换算成海平面高度的指示空速.
地速:飞机相对地面的速度.可以通过地面导航台、GPS等测得。
马赫数:真空速和音速的比值.
表速和真速的数值是不同的,主要原因是飞机空速管并不能测出飞机的飞行速度,
而只能测量出q=0.5*ro*v*v(其中ro是空气密度,v是飞机相对于空气的速度),然后用q
除以密度ro再除以0.5,将结果开方(通过电路或机构实现)即可得到飞行速度。但除
以密度时只能用海平面的密度值,而空气密度随着高度升高在减小,所以表速(仪表显
示的速度)就和真速不一致,比真速要小,高度越高,差别越大。
在无风的状态下,真速和地速是一致的;有风的情况下,真速和地速是不一致的,
真速和风速之和(矢量和)等于地速。注意这种情况仅适用于平飞,如果你是在爬升或
者下降状态,无风时地速不等于真速,种情况下地速只等于飞机真速的水平分量。 |
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m**********e 发帖数: 12525 | 27 你这物理phd都是怎么拿的?
你忘了爱因斯坦怎么从Mach's conjecture得出广义相对论的?
当然可以通过逻辑推理从已知得出未知,
另外,大量数学证明都是从已知(axiom)用纯粹逻辑推理得出新结论的 |
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w********2 发帖数: 632 | 28 https://sploid.gizmodo.com/5511236/the-thrill-of-flying-the-sr-71-blackbird
"I quickly increased our speed, calculating the time it would take for the
weapons-most likely SA-2 and SA-4 surface-to-air missiles capable of Mach 5
- to reach our altitude. I estimated that we could beat the rocket-powered
missiles to the turn and stayed our course, betting our lives on the plane's
performance." |
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w********2 发帖数: 632 | 29 "I was with the 5th Bomb Wing, Travis (1967 - 1971) and on a few occasions
saw the Blackbird at Beale, which was north of Travis. I also accompanied
our wing commander into the flight ops center. He asked me to wait for him
at the back of the room while he talked with three other officers. While
waiting, I happened to see a black book titled "U.S. Air Force Aircraft",
published by the Air Force as a reference tool for identifying planes. As I
thumbed through it, I just happened to flip to the SR... 阅读全帖 |
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t*****a 发帖数: 5180 | 31 Feng Lu, Xiaowu Chen, Imari Sato, Yoichi Sato:
SymPS: BRDF Symmetry Guided Photometric Stereo for Shape and Light Source
Estimation. IEEE Trans. Pattern Anal. Mach. Intell. 40(1): 221-234 (2018)
可惜了,陈老湿的科研还是不错的,和日本人合作的,这些工作11公, 能教授之流半文
科骗子们,打死了都做不出来的。 |
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m**c 发帖数: 7349 | 32 At a height of about 100 km, the Falcon 9 fairing separates from the second
state rocket, traveling at Mach 10.
Each of the two 1000-kg half-shells tumbles down at high speeds; cold
nitrogen thrusters will be used to stabilize the awkward-shaped fairing
piece and orient it into a more aerodynamic posture.
After it has fallen to an altitude of about 8 km and has slowed down
considerably by atmospheric drag, a GPS-equipped steerable parachute (
parasail) will be deployed which will “gently” guide ... 阅读全帖 |
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x******g 发帖数: 33885 | 34 地对舰导弹YJ-12B有效射程295海里
HQ-9B地对空导弹射程160海里
The Chinese land-based anti-ship cruise missile is believed to be the YJ-12B
, which would allow China to strike surface vessels within 295 nautical
miles of the reefs. The long-range surface-to-air missiles are the HQ-9B,
which can engage targets at ranges of 160 nautical miles. Intelligence
assessments say the missile platforms were moved to the outposts in the
Spratly Islands within the past 30 days, according to sources who spoke to
CNBC on the conditio... 阅读全帖 |
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s*****V 发帖数: 21731 | 35 图文并茂看这里
http://www.gzhshoulu.wang/article/736491
从古至今,无论在自然科学还是人文社科方面,学科分支越来越细,内容也越来越丰富
。究其原因,一方面是工具的增加,使人们发现不同现象的能力比以往更强。另一方面
,伴随着全世界人口大量增长,不同种族、宗教、习俗的人在互相交流后,他们的观点
和学问得到融会贯通,从而迸发出新的火花。
两千多年前,孔子谈论自己的学问时曾说:“吾道一以贯之”。面对越来越纷繁复杂的
学科,今天的学者还能做到孔子所说的“一以贯之”吗?我将探讨这个问题。
最重要的是
创造力和脚踏实地基础上的丰富情感
在建构一门新的学问,或是引导某一门学问走向新的方向时,学者的原创力从何而来?
为什么有些人看得特别远,找得到前人没有发现的观点?这是一种本能的理性选择,还
是读书破万卷的结果?诸多因素当然都极其重要,但在这其中,我认为最重要的是创造
力和脚踏实地基础上的丰富情感。
在中国文学史上,屈原作《楚辞》,李陵作《河梁送别诗》,太史公作《史记》,诸葛
亮作《出师表》,曹植作《赠白马王彪诗》,庾信作《哀江南赋》,王粲作《登楼赋》
,陶渊明作... 阅读全帖 |
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发帖数: 1 | 37 @juliijulii_
Zwei Monate keinen Ohrring getragen, zack, Löcher zugewachsen.
Langsam mach ich mir Sorgen um andere Löcher. |
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l*****O 发帖数: 402 | 38 “从来没有”只有傻逼会用。USN F/A-18s vs. IRAF MiG-25s On the first night of
the first gulf war, two F/A-18s from the carrier USS Saratoga were flying
outside of Baghdad when two Iraqi MiG-25PDs interceptors from the 96th
Squadron engaged them. In the beyond-visual-range (BVR), one of the Iraqi
MiGs, piloted by Lieutenant Colonel Zuhair Dawood, fired an R-40 missile,
shooting down one of the F/A-18's as it was travelling Mach 0.92. The pilot,
Lieutenant Commander Scott Speicher, was killed. It is widely beli... 阅读全帖 |
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w*p 发帖数: 16484 | 39 没事,楼主在本版的名气和地位早就建立起来了
: “从来没有”只有傻逼会用。USN F/A-18s vs. IRAF MiG-25s On the first
night of
: the first gulf war, two F/A-18s from the carrier USS Saratoga were
flying
: outside of Baghdad when two Iraqi MiG-25PDs interceptors from the 96th
: Squadron engaged them. In the beyond-visual-range (BVR), one of the
Iraqi
: MiGs, piloted by Lieutenant Colonel Zuhair Dawood, fired an R-40
missile,
: shooting down one of the F/A-18's as it was travelling Mach 0.92. The
pilot,
: ... 阅读全帖 |
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k***n 发帖数: 1557 | 40 微内核不新鲜,DOS就是微内核。
微内核先天缺陷很多,现在已经很少有人用了。洪门如果真的是用微内核,肯定是在
Mach内核上改的。 |
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k***n 发帖数: 1557 | 41 MacOS的前身是NextStep,是在Mach内核上加了一BSD层
FreeBSD的前身是386 BSD和4.4BSD。但是现在的FreeBSD已经没有原始Unix代码
至于Android算不算基于Linux,现在还有争议 |
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k***n 发帖数: 1557 | 42 微内核不是什么新技术,DOS就是微内核
微内核代码少,代价就是功能简单。所以Mac OS必须要在mach内核上再加一个BSD层
而且微内核不能像宏内核一样直接调用函数,效率反而更低 |
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t*****r 发帖数: 543 | 44 Wuhan residents say coronavirus figures released by China don't add up
Get all the latest news on coronavirus and more delivered daily to your
inbox. Sign up here.
Chinese officials, desperate to recast the country as a global leader that
has conquered the coronavirus, have been saying that its death rates are
decreasing in the city of Wuhan. The problem, residents say, is that the
numbers don't add up.
Wuhan, the first epicenter of the global outbreak, began lifting its two-
month lockdown over... 阅读全帖 |
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d********r 发帖数: 303 | 45 狂风的基本数据:
* Empty weight: 13,890 kg (31,620 lb)
* Max takeoff weight: 28,000 kg (61,700 lb)
* Maximum speed: Mach 2.34 (2,417.6 km/h, 1,511 mph)
* Range: 1,390 km (870 mi) typical combat
* Ferry range: 3,890 km (2,417 mi) with four external drop tanks
* Service ceiling: 15,240 m (50,000 ft)
* Rate of climb: 76.7 m/s (15,100 ft/min)
* Thrust/weight: 0.55
Armament
* Guns: 2× 27 mm Mauser BK-27 cannon with 180 rounds per gun (versus 1
× BK-27 mounted on Panavia To |
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p******y 发帖数: 3742 | 46 难道没有加力燃烧室?
不过我找到的wiki:
Maximum speed: Mach 0.95 (525 knots, 604 mph, 972 km/h) |
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B*D 发帖数: 5016 | 47 In its first flight attempt, the Boeing [NYSE: BA] X-51A WaveRider today su
ccessfully completed the longest supersonic combustion ramjet-powered flight
in history -- nearly three and a half minutes at a top speed of Mach 5.
The unmanned aerial vehicle was released from a U.S. Air Force B-52H bomber
off the southern California coast around 10 a.m. today. It flew autonomously
for more than 200 seconds, powered by its Pratt & Whitney Rocketdyne supers
onic combustion ramjet (scramjet) motor, as it |
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k***d 发帖数: 113 | 48 AIM-9 Sidewinder Specification
Specifications
Primary Function Air-to-air missile
Contractor Naval Weapons Center
Power Plant Hercules and Bermite Mk 36 Mod 71, 8 solid-propellant rocket
motor
Thrust Classified
Speed Supersonic Mach 2.5
Range 10 to 18 miles depending on altitude
Length 9 feet, 5 inches (2.87 meters)
Diameter 5 inches (0.13 meters)
Finspan 2 feet, 3/4 inches (0.63 meters)
Warhead Annular blast fragmentation warhead
25 lbs high explosive for AIM-9H |
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w******n 发帖数: 13172 | 49 貌似几乎所有的跟帖都认可tg可以实现,都在讨论如何从政治上反制或用激光自卫。
http://www.usni.org/news-and-features/chinese-kill-weapon
Report: Chinese Develop Special "Kill Weapon" to Destroy U.S. Aircraft
Carriers
Advanced missile poses substantial new threat for U.S. Navy
U. S. Naval Institute
March 31, 2009
With tensions already rising due to the Chinese navy becoming more
aggressive in asserting its territorial claims in the South China Sea, the U
.S. Navy seems to have yet another reason to be deeply concerned.
After years of c... 阅读全帖 |
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w******n 发帖数: 13172 | 50 关于天波雷达:* OTH Radar - Has a range of 800 to 3000 km. The accuracy in
targetting is around 20 to 30 km. This can be improved to 2 to 3 km with
improved algorithm. OTH radar can work with the recon satellites to provide
more accurate targeting info.
http://www.informationdissemination.net/2009/03/plan-asbm-development.html
Saturday, March 28, 2009
PLAN ASBM development
I was contacted by Galrahn to read over a Chinese blog entry on PLAN's ASBM
development (found here) and post my thoughts on it.
I ... 阅读全帖 |
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