在调速系统中改变电动机转速的是()。A、电压负反馈 B、转速负反馈 C、给定电压 D

来源:www.tikuol.com 发布时间:2019-08-13 16:24
题型:单项选择题

问题:

在调速系统中改变电动机转速的是()。

A、电压负反馈

B、转速负反馈

C、给定电压

D、电流正反馈

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题型:单项选择题

28岁男性,踢足球时摔伤左膝,1个月后仍疼痛。查体:右膝肿胀,浮髌试验阳性,前抽屉试验阳性,侧方应力试验阴性。

最可能的诊断是

A.前交叉韧带损伤

B.后交叉韧带损伤

C.外侧副韧带损伤

D.内侧副韧带损伤

E.外侧半月板损伤

题型:解答题

两位同学将一个二次三项式分解因式,一位同学因看错了一次项系数而分解成2(x-1)(x-9),另一位同学因看错了常数项而分解成2(x-2)(x-4),请将原多项式分解因式.

题型:单项选择题

下列体积换算正确的是

A.1L=103dm3
B.1L=106dm5
C.1L=10-3m3
D.1L=10-6m3
E.1L=103m3

题型:多项选择题

IntroductionShoal plc is a well-known corporate organisation in the fi sh industry. It owns 14 companies concerned with fi shing and related industries.This scenario focuses on three of these companies:ShoalFish Ltd – a fi shing fl eet operating in the western oceansShoalPro Ltd – a company concerned with processing and canning fi shShoalFarm Ltd – a company with saltwater fi sh farms.Shoal plc is also fi nalising the purchase of the Captain Haddock chain of fi sh restaurants.ShoalFishShoal plc formed ShoalFish in 2002 when it bought three small fi shing fl eets and consolidated them into one fl eet. The primary objective of the acquisition was to secure supplies for ShoalPro. 40% of the fi sh caught by ShoalFish are currently processed in the ShoalPro factories. The rest are sold in wholesale fi sh markets. ShoalFish has recorded modest profi ts since its formation but it is operating in a challenging market-place. The western oceans where it operates have suffered from many years of over-fi shing and the government has recently introduced quotas in an attempt to conserve fi sh stocks.ShoalFish has 35 boats and this makes it the sixth largest fl eet in the western oceans. Almost half of the total number of boats operating in the western oceans are individually owned and independently operated by the boat’s captain. Recent information for ShoalFish is given in Figure 1.ShoalProShoalPro was acquired in 1992 when Shoal plc bought the assets of the Trevarez Canning and Processing Company. Just after the acquisition of the company, the government declared the area around Trevarez a ‘zone of industrial assistance’. Grants were made available to develop industry in an attempt to address the economic decline and high unemployment of the area. ShoalPro benefi ted from these grants, developing a major fi sh processing and canning capability in the area. However, despite this initiative and investment, unemployment in the area still remains above the average for the country as a whole.ShoalPro’s modern facilities and relatively low costs have made it attractive to many fi shing companies. The fish received from ShoalFish now accounts for a declining percentage of the total amount of fi sh processed and canned in its factories in the Trevarez area. Recent information for ShoalPro is given in Figure 1.ShoalFarmShoalFarm was acquired in 2004 as a response by Shoal plc to the declining fi sh stocks in the western oceans. It owns and operates saltwater fi sh farms. These are in areas of the ocean close to land where fi sh are protected from both fi shermen and natural prey, such as sea birds. Fish stocks can be built up quickly and then harvested by the fi sh farm owner. Shoal plc originally saw this acquisition as a way of maintaining supply to ShoalPro.Operating costs at ShoalFarm have been higher than expected and securing areas for new fi sh farms has been diffi cult and has required greater investment than expected. Recent information for ShoalFarm is given in Figure 1.

Figure 1: Financial data on individual companies 2007–2009Captain HaddockThe Captain Haddock chain of restaurants was founded in 1992 by John Dory. It currently operates one hundred and thirty restaurants in the country serving high quality fi sh meals. Much of Captain Haddock’s success has been built on the quality of its food and service. Captain Haddock has a tradition of recruiting staff directly from schools and universities and providing them with excellent training in the Captain Haddock academy. The academy ensures that employees are aware of the ‘Captain Haddock way’ and is dedicated to the continuation of the quality service and practices developed by John Dory when he launched the fi rst restaurant. All management posts are fi lled by recruiting from within the company, and all members of the Captain Haddock board originally joined the company as trainees. In 1999 the Prime Minister of the country identifi ed Captain Haddock academy as an example of high quality in-service training. In 2000, Captain Haddock became one of the thirty best regarded brands in the country.In the past few years, the fi nancial performance of Captain Haddock has declined signifi cantly (see Figure 2) and the company has had diffi culty in meeting its bank covenants. This decline is partly due to economic recession in the country and partly due to a disastrous diversifi cation into commercial real estate and currency dealing. The chairman and managing director of the company both resigned nine months ago as a result of concern over the breaking of banking covenants and shareholder criticism of the diversifi cation policy. Some of the real estate bought during this period is still owned by the company. In the last nine months the company has been run by an interim management team, whilst looking for prospective buyers. At restaurant level, employee performance still remains relatively good and the public still highly rate the brand. However, at a recent meeting one of the employee representatives called for a management that can ‘effectively lead employees who are increasingly demoralised by the decline of the company’.Shoal plc is currently fi nalising their takeover of the Captain Haddock business. The company is being bought for a notional $1 on the understanding that $15 million is invested into the company to meet short-term cash fl ow problems and to improve liquidity. Shoal plc’s assessment is that there is nothing fundamentally wrong with the company and that the current fi nancial situation is caused by the failed diversifi cation policy and the cost of fi nancing this. The gross profi t margin in the sector averages 10%.Captain Haddock currently buys its fi sh and fi sh products from wholesalers. It is the intention of Shoal plc to look at sourcing most of the dishes and ingredients from its own companies; specifi cally ShoalFish, ShoalPro and ShoalFarm. Once the takeover is complete (and this should be within the next month), Shoal plc intends to implement signifi cant strategic change at Captain Haddock so that it can return to profi tability as soon as possible. Shoal plc has implemented strategic change at a number of its acquisitions. The company explicitly recognises that there is no ‘one right way’ to manage change. It believes that the success of any planned change programme depends on an understanding of the context in which the change is taking place.

Figure 2: Financial information for Captain Haddock 2007–2009Required:

(c) Portfolio managers, synergy managers and parental developers are three corporate rationales for adding value.Explain each of these separate rationales for adding value and their relevance to understanding the overall corporate rationale of Shoal plc. (10 marks)

题型:单项选择题

淬火后主要获得的室温组织为()

A、奥氏体

B、渗碳体

C、贝氏体

D、马氏体或贝氏体