【判断题】. 为了调整硬度,便于机械加工,低碳钢、低碳低合金钢在锻造后应采用正火处理。

【简答题】请大家自由分组,原则上3人一组(成员不足时,2人亦可),以PPT形式提交作业,PPT中一定要写清楚每个成员的名字,并按照第一周课堂上讲过的PPT格式来设计。另外,请注意每个小组成员均需提交一次PPT,否则无法打分。谢谢大家! Task Two.docx Resources: Harold Godwinson https://www.ancient.eu/Harold_Godwinson/ https://monstertubenetwork.com/facts-about-harold-godwinson/ https://factsking.com/historical-people/harold-godwinson-facts/ http://primaryfacts.com/3431/king-harold-ii-facts-about-harold-godwinson/ https://www.bbc.co.uk/history/historic_figures/harold_ii_godwineson.shtml https://www.britannica.com/biography/Harold-II Harald Hardrada https://www.historyhit.com/1066-harald-hardraada-lands-england/ http://www.ancientfacts.net/about/harald-hardrada/ https://norse-mythology.net/harald-hardrada-facts/ https://factsking.com/historical-people/harald-hardrada-facts/ http://historylearning.com/medieval-england/harald-hardrada/ https://spartacus-educational.com/MEDhardrada.htm https://www.learnodo-newtonic.com/harald-hardrada-facts https://www.britannica.com/biography/Harald-Hardrada William Duke of Normandy https://www.bbc.com/timelines/zp88wmn https://www.britannica.com/biography/William-I-king-of-England https://www.britannica.com/biography/William-I-duke-of-Normandy https://factfile.org/10-facts-about-duke-william-of-normandy https://www.biography.com/royalty/william-the-conqueror https://www.normandythenandnow.com/rebellion-and-the-epic-gallop-of-william-duke-of... https://www.reference.com/history/did-william-normandy-think-should-king-england-ca9cad8bc96189d1 Other websites https://www.bbc.co.uk/bitesize/guides/zy7n4j6/revision/2 https://www.historyhit.com/the-claimants-to-the-english-throne-in-1066 https://history.blog.gov.uk/2016/01/05/the-death-of-edward-the-confessor-and-the-conflicting-claims-to-the-english-crown/ https://schoolshistory.org.uk/topics/british-history/normans/claimants-throne-1066/ www.normaninvasion.info/claims-throne-england-1066.htm Note: Some of the websites may be accessible only via a VPN.

【单选题】下列叙述正确的是() (4.0分)

【单选题】周期矩形脉冲序列的频谱的谱包络线为( ) (4.0分)

【单选题】一个周期信号 f(t) ,周期为 T ,其频谱图中相邻两条谱线之间的间隔为() (4.0分)

【简答题】Shakespeare has Juliet say: What's in a name? That which we call a rose. By any other name would smell as sweet. What do the above lines say to you about the relationship between the form (sounds) and meaning ( concept) of a word in spoken language? Explain with positive evidence as well as exceptions from the English language. (北外 2004)

【其它】write the second report about 250 words.

【单选题】关于抽样信号 ,下列说法错误的是() (4.0分)

【其它】新的开局预算方案。 沙盘预算表 .xls 上交的文档名:第三次沙盘预算表-**组

【判断题】在 Fe-Fe 3 C 相图的 PSKLQP 区域中存在 Fe 3 C I、 Fe 3 C II、 Fe 3CIII、共晶渗碳体、共析渗碳体,它们都属于同一种相组成物。

【单选题】设一个矩形脉冲的面积为S,则矩形脉冲的傅氏变换的 的函数值等于( ) (4.0分)

【简答题】在下图中增加两个接触器,完成双速电机的△接法和YY接法主回路。

【判断题】热处理的特点是不改变零件的外形和尺寸,只改变其内部组织和性能。

【单选题】已知 是周期为T的函数, 的傅里叶级数中,只可能有( ) (4.0分)

【单选题】满足傅氏级数收敛条件时,周期信号f(t)的平均功率( ) (4.0分)

【简答题】Read the following paragraph and list all the function words you can find,(Include all forms of be as function words. Give the percentage of function words in this paragraph She was a small woman, old and wrinkled. When she started washing for us, she was already past seventy. Most Jewish women of her age were sickly, weak, broken in body. But this washwoman small and thin as she was, possessed a strength that, came from generations of peasant ancestors. Mother would count out to her a bag of laundry that had accumulated over several weeks. She would lift the heavy bag, load it on her narrow shoulders, and carry it the long way home.

【单选题】连续周期信号f(t)的频谱 的特点是() (4.0分)

【简答题】Suppose you and your family are offered a great chance to move to the UK, though it is a non-immigration nation. You’re free to choose any place you like within the country. Do online research and think carefully where you are going to settle down. Choose wisely and provide at least three reasons to support your decision. You may need to consider factors such as geographical position, climate, natural environment, educational resources, level of income, living costs, local people and culture, leisure and entertainment etc.. Please write your responses in English and check through your answers to make sure there’re no spelling mistakes or grammatical errors. Word limit: 200 words. You may visit the following websites to do your research, and you are welcomed to share your own resource list at the end of your work. Resources: British Cities and Places https://www.tripsavvy.com/popular-uk-cities-for-international-visitors-1661845 https://happytowander.com/most-beautiful-places-in-england/ https://www.buzzfeed.com/ailbhemalone/spectacular-places-in-britain-you-have-to-visit-before-yo Geography of the UK http://www.projectbritain.com/geography.html https://www.britannica.com/place/United-Kingdom https://www.thoughtco.com/geographic-regions-of-the-united-kingdom-1435712 Climate in the UK http://www.lordgrey.org.uk/~f014/usefulresources/aric/Resources/Teaching_Packs/Key_Stage_3/Weather_Climate/09.html http://projectbritain.com/climate.html British People and Culture https://www.biography.com/people/groups/people-from-great-britain https://www.learnenglish.de/britishculture.html https://factfile.org/10-facts-about-british-culture https://www.gapyear.com/articles/opinion/12-stereotypes-british-people-travel http://projectbritain.com/index/people.htm https://www.angmohdan.com/48-things-british-people-say-and-what-they-actually-mean/

【判断题】预备热处理主要用来改善钢的工艺性能,最终热处理主要用来改善钢的使用性能。

【单选题】奇函数的傅里叶级数展开式中( ) (4.0分)

【单选题】的傅立叶变换为() (4.0分)

【单选题】过共析钢的含碳量是 _________ 。

【判断题】( )多速电动机启动时宜先接成低速,然后再换接成高速。

【单选题】犀角地黄汤的适应证是

【单选题】过冷奥氏体向贝氏体的转变是________。

【单选题】若矩形脉冲信号宽度加宽,则它的频谱带宽() (4.0分)

【单选题】奇谐函数的傅里叶级数展开式中( ) (4.0分)

【单选题】低碳钢正火的目的是_________。

【单选题】某一周期函数,在其频谱分量中,仅含有正弦基波分量和正弦奇次谐波分量,该函数属于( ) (4.0分)

【其它】writing the reading report about 250 words.

【简答题】例题验证

【判断题】热处理的种类有很多,但一般都是由加热、保温和冷却三个阶段组成。

【简答题】In some dialects of English the following words have different vowels, as is shown by the phonetic transcriptions A B C bite /b Q jt/ bide /bajd/ die /daj/ rice /r Q js/ rise /rajz/ by /baj/ ripe /r Q jp/ bride /brajd/ sigh /saj/ wife /w Q jf/ wives /wajvz/ rye /raj/ dike /d Q jk/ dime /dajm/ guy /gaj/ nine /najn/ rile /rajl/ dire /dajr/ writhe /raj T / a. How may the classes of sounds that end the words in columns A and B be characterized? T hat is, what feature specifies all the final segments in A and all the final segments in B? b. How do the words in column C differ from those in columns A and B? c. Are [ Q j] and [aj] in complementary distribution? Give your reasons. d. I f [ Q j] and [aj] are allophones of one phoneme, should they be derived from/ Q j/ or /aj/? W hy? e. Give the phonetic representations of the following words as would be spoken in the dialect described here: life lives lie file bike lice f. Formulate a rule that will relate the phonemic representations to the phonetic representations of the words given above.

【单选题】等于( ) (4.0分)

【单选题】满足狄里赫利收敛条件时,傅氏级数与原周期信号f(t)之间() (4.0分)

【判断题】为了得到均匀的奥氏体,保温时间越长越好

【其它】开局预算方案。 沙盘预算表 .xls 上交的文档名:沙盘预算表-**组

【单选题】信号 的表达式为( ) (4.0分)

【简答题】T12 钢加热到Ac1+30°C,保温后用图7示各种方法冷却,分析其所得到的组织分别是什么?

【单选题】频谱函数 的傅立叶反变换f(t)为() (4.0分)

【判断题】正火和退火的主要区别是加热温度的不同。

【单选题】偶函数的傅里叶级数展开式中() (4.0分)

【单选题】符号函数sgn(t) 的频谱函数为() (4.0分)

【简答题】求周期信号 的基波角频率Ω 和周期T,并画出单边频谱 (10.0分)

【单选题】若f(t)是实偶信号,下列说法正确的是() (4.0分)

【判断题】原始组织为片状珠光体的共析钢加热奥氏体化时,细片状珠光体的奥氏体化速度比粗片状珠光体的快。

【简答题】求取样函数 的频谱函数 (10.0分)

【判断题】()双速电机的YY接法所形成的磁极对数是△接法的一半。

【判断题】共析成分的过冷奥氏体发生珠光体转变时,转变温度越低,其转变产物组织越粗。

【判断题】生产中实际加热时发生相变的临界点用A1、A3、Acm来表示。