外文翻譯--具有目的地管理能力電梯的運輸性能研究

1、<p>　　3000英文單詞，1.5萬英文字符，中文5200字</p><p>　　文獻出處：Lauener J. Traffic performance of elevators with destination control[J]. Elevator world, 2007, 55(9): 86.</p><p>　　畢業(yè)設計（論文）外文文獻翻譯</p>&l

2、t;p>　　Traffic Performance of Elevators with Destination Control</p><p><b>　　J Lauener</b></p><p>　　This article highlights the attributes of destination control with regard to the

3、 resulting traffic performance and, in the absence of a traffic-simulation program, offers a shortcut method that allows assessment of the up-peak traffic performance using conventional traffic-analysis software to obtai

4、n results. It is a rudimentary but</p><p>　　useful tool, especially during building-core design, where it quickly displays a suitable layout of the vertical-transportation system, along with options and comp

5、arisons. Generally, stage one of a building’s design is to determine the core layout before going any further by positioning and fixing the number of required elevator shafts, the zoning of elevators, the location of mac

6、hine rooms, and sky lobbies and escalators (if applicable).</p><p>　　However, there are so many different design options available on the market that for larger projects, it would be prudent to get an equipm

7、ent update from the major elevator suppliers and select the most suitable of all possible layout options before settling on the final tender specification. At the early design stage, the main criterion would be to arrive

8、 at a vertical-transportation arrangement that can achieve the required traffic performance with minimal hardware and space requirements. Othe</p><p>　　The application of different options also changes with

9、the type of building (residential, office, hotel, mixed purpose, special purpose), and different elevator suppliers can offer different solutions. Any one of them could entail:</p><p>　　Elevators, escalators

10、 or moving walks</p><p>　　Passenger, service, goods or other purpose elevators</p><p>　　Single zoning or sub-zoning</p><p>　　Direct elevatoring from the main entrance (including sky

11、 lobbies) fed by express elevators from the main entrance</p><p>　　Up/down elevatoring of local elevator groups from sky lobbies</p><p>　　Single-deck, double-deck or tripledeck elevators</p&g

12、t;<p>　　Elevators with or without machine rooms</p><p>　　Destination control or conventional control</p><p>　　Elevators of the same group serving different floors</p><p>　　Ha

13、ndicapped requirements</p><p>　　Special access and security requirements ,etc.</p><p>　　However, this article will focus on describing a simple method that can determine the up-peak traffic perf

14、ormance of elevators with destination group control (DGC), which usually shows that the same performance can be achieved with a reduced number of elevators compared to the number of units of a conventional group control

15、(CGC). (Since not all elevator suppliers offer destination control, tender specifications often allow for both types of control.)</p><p>　　DGC Vs CGC</p><p>　　During the design stage of a buildi

16、ng, a speedy answer to the traffic performance of different vertical-transportation arrangements is desirable. Most building designers may be familiar with using conventional software for elevator-traffic analyses of CGC

17、 systems, but not necessarily so for those of DGC. This simplified method allows for the determination of the traffic performance of elevators with DGC by using the same conventional software as for CGC with the aim to e

18、fficiently arrive at a us</p><p>　　be carried out to verify the preliminary traffic-performance results and cover the down-peak and two-way traffic modes.</p><p>　　For the elevator user, the fun

19、damental difference between the CGC and DCG systems lies in the registration of the hall and car calls, and signage. In the case of CGC, an elevator is called to a landing by registering a hall call in the landing-button

20、 board. When the elevator arrives, the elevator user will enter the car and register a call in the car panel to travel to the selected floor.</p><p>　　In the case of DGC, there are no call panels inside the

21、cars because elevator users key in their destinations at the lobby before entering a car. When registering a call, an indicator built into the landing-button pad will then immediately show which of the elevators in the g

22、roup has been assigned to service that particular call. For identification purposes, the elevators in a group are usually designated with letters A, B, C . . . The signage is further enhanced by indicators placed in the

23、entr</p><p>　　Traffic Performance Comparison Between DGC and CGC</p><p>　　Roundtrip time (RTT) is a direct measurement of the transportation efficiency of elevators. Looking at an uppeak traffic

24、 condition, the average RTT under DGC will be considerably shorter, because DGC organizes the traffic in such a manner that the elevators only stop at a reduced number of floors during each roundtrip. The reason for such

25、 an improvement is that when elevator users key in their destinations at the lobby, same-floor passengers will be directed to enter the same car, i.e., a car wi</p><p>　　In the case of CGC, since the control

26、 system remains oblivious as to which floors passengers intend to travel to until their destinations have been registered inside the car via the car panel, the cars are randomly filled with passengers having many differe

27、nt floor destinations, which then forces the elevators to stop at that many floors, thus slowing down the elevator service. For example, with CGC, a 1600-kg capacity car serving 15 upper floors will on average stop at 10

28、-11 different floors du</p><p>　　Traffic Analyses – Up-Peak Condition Basic Data Required</p><p>　　A traffic analysis is pretty straightforward unless some special factors have to be considered

29、such as floors for restaurants, banking, conventions, clubs, car parks, basements, etc. The basic data required to carry out a traffic analysis can be limited to the following four items:</p><p>　　Number of

30、tenants on upper floors (assuming same average numbers per floor)</p><p>　　Number of floors to be served</p><p>　　Travel distance from main entrance to top floor and main entrance to first upper

31、 floor</p><p>　　Required handling capacity</p><p>　　The following parameters are then determined in accordance with usual industry standards:</p><p>　　Car capacity</p><p&

32、gt;　　Car fill factor</p><p>　　Door type (center opening or telescopic) and door width</p><p>　　Elevator speed Other parameters of the program are:</p><p>　　Average weight per passen

33、ger (usually 68-75 kilograms, but dependent upon the prevailing code of practice [COP])</p><p>　　Passenger transfer time (average time per passenger to enter and egress a car)</p><p>　　Door open

34、ing/closing time</p><p>　　Door block time (time delay before door closing after last person has passed through)</p><p>　　Premature door open time (initiation of door opening before car has reach

35、ed floor level). Premature door opening may not be allowed under some COPs.</p><p>　　Brake-release time</p><p>　　Drive startup delay time</p><p>　　Rate of acceleration/deceleration&

36、lt;/p><p>　　Jerk (rate of change of acceleration/deceleration)</p><p><b>　　Example</b></p><p>　　For DCG, take a simple office building with the following specifications:<

37、;/p><p>　　Number of floors to be served: 16 (G, 1-15)</p><p>　　Travel distance: G/F-15/F: 64 meters; G/F-1/F: 8 meters</p><p>　　Number of tenants on upper floors: 1,200 (an average of

38、80 persons per floor)</p><p>　　Required five-minute handling capacity: 15%</p><p>　　The computer input data for DGC shall be the same as for CGC, except for the average number of upper floors to

39、 be served per elevator per roundtrip and the average car fill factor. The two parameters differ for the following reasons:</p><p>　　Average number of floors served per elevator per roundtrip: The control sy

40、stem under DGC constantly endeavors to equalize the workload among the elevators in the same group. This means that, for instance, with 15 office floors to be served by a group of eight elevators, the control system shou

41、ld on average ideally assign 15 floors/8 elevators = 1.875 stops per elevator per roundtrip (exclusively the mandatory stop at the ground floor). With a group of six elevators, the ideal load sharing would </p>&l

42、t;p>　　Figure 1: The typical duty assignment of destination control with ideal load sharing during an up-peak traffic condition. Each of the six elevators serves an average of 2.5 upper floors per roundtrip.</p>

43、<p>　　Average Car Fill Factor: Experience has shown that DGC cars are less crowded than those with CGC control. In our example for CGC, we assume an average car fill factor of 70%; for DGC, we assume a reduced car

44、fill factor of 60%. The car fill factor differs between different societies. In Asia, one would use a higher car fill factor than in the U.S. or Europe because of the difference in the average size of people and the diff

45、erence in culture. We first start by analyzing the traffic performance o</p><p>　　Input Data for DGC</p><p>　　For DGC, we use the same input data as above for CGC, except for the number of floor

46、s to be served per elevator (per roundtrip) and the average car fill factor. We</p><p>　　first start by determining the average number of stops an elevator will have to make per roundtrip. The number of stop

47、s per roundtrip changes with the number of elevators involved and, since the number of elevators with DGC can usually be reduced, we determine here that the number of stops (exclusive of the ground floor) is also based o

48、n some smaller car groups to check their traffic performance, i.e.:</p><p>　　For 8 elevators: 3 stops per roundtrip (15 Floors/8 elevators + 0.5, rounded up to next integer)</p><p>　　For 7 eleva

49、tors: 3 stops per roundtrip</p><p>　　For 6 elevators: 4 stops per roundtrip</p><p>　　For 5 elevators: 4 stops per roundtrip</p><p>　　One cannot be sure of the number of stops (upper

50、 floors) to use in the analysis, because the number of elevators required is still unknown. In this example, we start</p><p>　　with three upper floors and check the result with regard to the handling capacit

51、y achieved and the number of elevators required. If it shows that a group of seven or eight elevators will be required to meet the handling capacity of 15%, then the applied number of three upper floors is correct. On th

52、e other hand, if the handling capacity is far above the required 15% target, fewer elevators are required, and the analysis has to be repeated (in this case, with four or more upper floors). Table 2 s</p><p>

53、;　　The above table’s RTTs for car groups of eight and seven, and six and five elevators are the same because the numbers of floors applied are the same. In this example, the result shows that DGC would require a group of

54、 six elevators to reach the required handling capacity of 15%, while CGC, as calculated earlier, would require eight elevators.</p><p>　　Further Points of Interest</p><p>　　Running a comparison

55、of the traffic performance between DGC and CGC with the same software will produce useful results precisely because the only variable will be the number of stops per roundtrip and the car fill factor. The described short

56、cut method of traffic analysis for DGC is meant to produce conservative results, and it further served the purpose here to demonstrate the difference in traffic performance between DGC and CGC. Below some applied factors

57、 of prudence:</p><p>　　The ideal average number of stops assigned per roundtrip is added by 0.5 stops and rounded up to the next integer. </p><p>　　In this method, we use the full travel height

58、to calculate the RTT, although the elevators will, on average, not have to travel the full height. While the elevators will, of course, service all floors including the top floor, some cars will return to the main landin

59、g from lower levels, all as dictated by the algorithm of the control system, thus resulting in a reduced average travel distance.</p><p>　　Because of the reduced number of stops per roundtrip, a higher numbe

60、r of passengers will egress cars at the same time, with the effect that the passenger transfer becomes more efficient and therefore the passenger transfer time could be somewhat reduced.</p><p>　　Reduced car

61、 fill factor (as compared with CGC).</p><p>　　Since the duty cycle of the elevators during up-peak is much more demanding than during down-peak with CGC, the determination of the required numbers of elevator

62、s has to be based on up-peak criteria. As a consequence, there is an inherent over-capacity of elevators during down-peak, achieving a higher than required handling capacity. The reason is that during up-peak with CGC, c

63、ars are randomly filled with passengers of many different floor destinations. This is not the case during down-peak mod</p><p>　　DGC has also been called an up-peak booster, which is certainly correct since

64、with the reduced number of stops during roundtrips, DGC does improve the up-peak performance significantly. One can say that DGC has brought the up-peak performance of the elevators into line with the otherwise much bett

65、er down-peak performance, resulting in a well-balanced utilization of the elevators. As shown, the persistent discrepancy in performance between up-peak and down-peak with CGC can be avoided with DGC co</p><p&

66、gt;　　There is, of course, still the two-way traffic to be considered, which can be most demanding to an elevator system. In an office building, two-way traffic will normally occur during working hours and lunchtime, when

67、 it will usually stay within moderate levels and is of little concern. Heavy two-way traffic can occur if, for instance, special-function floors like restaurant floors or convention floors, etc. are commonly served by el

68、evators that are also providing normal elevator service to other </p><p>　　By virtue of its characteristics, DGC allows more floors to be packed into the same zone than would be economically feasible with CG

69、C. This can be demonstrated by the results obtained from the example, where the office building under scrutiny requires eight elevators with CGC but only six with DGC to reach the required 15% handling capacity. Would on

70、e choose to retain the original eight elevators but controlled by DGC one could add an extra five floors to the original 15 office floors, thus serv</p><p>　　具有目的地管理能力電梯的運輸性能研究</p><p><b>　

71、　J Lauener</b></p><p>　　本文著重于電梯因有目的地管理能力而產(chǎn)生的運輸性能的研究，且在運輸仿真方案缺乏的情況下提出了一種快捷的方法，該方法能做到使用傳統(tǒng)的運輸分析軟件來評定電梯上行高峰時的運輸能力并獲得結果。這種方法十分基礎但非常有用，特別是設計建筑核心時，它能避免選擇和比較，快速顯示出一個垂直交通系統(tǒng)的合適布局。一般情況下，建筑設計的第一階段是在定位和修筑所有需要的電梯豎井、

72、電梯區(qū)間、機房位置、大廳、自動扶梯之前確定核心布局（如果適當）。</p><p>　　但是，現(xiàn)在市面上一個較大的項目里有太多不同的設計可供選擇，明智的做法是獲取一套主要電梯供應商最近更新的設備，并在決定最終的招標規(guī)格之前從所有可能的布局中選擇最有用的一個布局。在早期的設計階段中，最重要的標準應該是在用最少的硬件和最小的空間的條件下達到所要求的傳輸性能并實現(xiàn)垂直交通系統(tǒng)的布置。評標估算階段還需考慮諸如電梯承包商的工

73、作程序記錄、電梯安裝的價格協(xié)議、電梯維護的運行成本、由系統(tǒng)占用空間所造成收益損失和電力使用成本等因素。</p><p>　　方案的應用也會隨著建筑類型的不同（住宅、辦公樓、酒店、混合用途、特殊用途）而發(fā)生變化，且不同的電梯供應商也會提供不同的解決方案，其中任何一個解決方案都需要：</p><p>　　電梯、自動扶梯或自動人行道</p><p>　　客運、服務、貨物或

74、其他目的的電梯</p><p><b>　　單分區(qū)或子分區(qū)</b></p><p>　　直接用于主要入口的電梯（包括大廳）和貨運電梯</p><p>　　大廳電梯組中的上下電梯</p><p>　　單層、雙層或三層電梯</p><p><b>　　帶或不帶機房的電梯</b>&

75、lt;/p><p><b>　　目標控制或傳統(tǒng)控制</b></p><p>　　同組電梯服務不同樓層</p><p><b>　　殘疾人的要求</b></p><p>　　特殊通道和安全的要求等</p><p>　　但話又說回來，本文將側重于描述一個簡單的方法，它可以評定有目標控

76、制能力的電梯的上行高峰時的運輸能力（以下簡稱DGC），具有該能力的電梯與傳統(tǒng)管理組（以下簡稱CGC）電梯相比，通常能在實現(xiàn)相同性能的前提下減少電梯使用的數(shù)量。（因現(xiàn)如今不是所有電梯都具有目的地管理能力，故兩種類型的電梯都是被招標規(guī)格允許的。）</p><p>　　DGC Vs CGC</p><p>　　其實在建筑的設計階段，我們就可以快速分析出不同垂直交通布局的運輸性能。大多數(shù)建筑設計師

77、可能只熟悉使用傳統(tǒng)的CGC系統(tǒng)電梯運輸分析軟件，而不一定會使用那些對應于DGC系統(tǒng)的軟件。而我們這種簡便的方法就旨在使用傳統(tǒng)的CGC運輸分析軟件來定義DGC電梯的運輸性能，并得到有效且明智的結果。一旦布局決定下來且DGC的布置看起來是合理的，那么計算機就能仿真出符合先前運輸性能且涵蓋下行高峰和雙向特性的交通模型。</p><p>　　對電梯用戶來說，CGC系統(tǒng)和DGC系統(tǒng)的根本差別在與大廳人員登記、轎廂召喚和標志

78、上。在CGC下，電梯被召喚到有選層請求的樓層, 該請求是由該層層站按鈕面板登記并發(fā)送的。當電梯到達該層時，電梯使用者進入轎廂后在其內部的轎廂面板上選擇樓層并創(chuàng)建請求。</p><p>　　在DGC下，因為電梯用戶在進入轎廂之前就在門廳鍵入了他們的目的地，所以轎廂內部沒有轎廂面板。當一個請求被創(chuàng)建時，層站按鈕發(fā)射臺在內部建立一個指令并立即指定出電梯組中的哪臺電梯去服務那個請求。為了便于區(qū)分，一個電梯組的電梯通常用字

79、母A、B、C等標志開來，并在每個轎廂的入口列放置指示器來進一步增強標志，用于區(qū)分在即將到來的行程中，哪個轎廂將被用來服務于哪個目標樓層。在DGC系統(tǒng)后，目標樓層的分配是動態(tài)的，即對于每一個新的往返行程中，各臺電梯將被分配到不同的目標樓層去服務，以滿足不斷變化的運輸要求。</p><p>　　DGC運輸性能和CGC運輸性能的比較</p><p>　　往返行程時間（簡稱RTT）是一個能直接表現(xiàn)

80、電梯運輸效率的尺度。在上行高峰時，DGC的平均RTT大大縮短，因為DGC組織的交通方式是電梯在每個往返行程中只停層于越來越少的樓層。之所以這樣是因為當電梯用戶在門廳鍵入他們的目的地時，同目的地的乘客可以進入同一個轎廂，也就是說，滿滿一轎廂的用戶的目的地通常只有兩、三或四個樓層，其中目的地具體數(shù)目取決于電梯需要服務的樓層數(shù)目和電梯組的電梯數(shù)目。</p><p>　　在CGC情況下，只有在轎廂內的轎廂面板登記了某些目

81、標樓層之后，CGC系統(tǒng)才理會那些目標樓層中想坐電梯的乘客，所以轎廂內隨機的裝滿了想前往不同目的地的乘客，迫使電梯停在很多樓層，從而減慢了電梯的服務效率。例如，一個1600公斤容量的轎廂使用CGC系統(tǒng)服務一個15層的樓房，每個往返行程中轎廂將在不同的樓層平均停10-11次來讓每一個乘客離開轎廂，并且每次停站都將增加10秒的RTT。而相同情況下，一臺使用DGC系統(tǒng)的電梯只需停留大概兩、三或四個不同的目標樓層。此外，由于往返行程中停層次數(shù)較少

82、，電梯在停站時所用的平均時間也比CGC更少，進一步的縮短了RTT值。</p><p>　　運輸分析—上行高峰時所需基本數(shù)據(jù)</p><p>　　運輸分析不是個難活，除非需要考慮一些特別因素，如樓房為餐廳、銀行、會議樓、俱樂部、停車場、地下室等。運輸分析所需的基本數(shù)據(jù)限于以下四個類型：</p><p>　　上方樓層的用戶數(shù)量（假定每層平均數(shù)目相同）</p>

83、<p><b>　　需要服務的樓層數(shù)量</b></p><p>　　主要入口到頂層和到第一個上方樓層分別的行程距離</p><p><b>　　需要的處理能力</b></p><p>　　下面的參數(shù)按照通常行業(yè)標準來確定：</p><p><b>　　轎廂容量</b&g

84、t;</p><p><b>　　轎廂裝載率</b></p><p>　　電梯門類型（中開式或伸縮式）和門寬</p><p><b>　　電梯速度</b></p><p>　　運輸分析的其他參數(shù)：</p><p>　　每名乘客平均重量（通常是68-75公斤，也取決于現(xiàn)行法規(guī)（

85、簡稱COP））</p><p>　　乘客中轉時間（每名乘客進入和離開轎廂的平均時間）</p><p><b>　　電梯門開關門時間</b></p><p>　　電梯門攔截時間（最后一人穿過電梯門之后門保持打開狀態(tài)的時間）</p><p>　　電梯門提前開門時間（轎廂到達樓層水平面之前電梯門就開始開啟）</p>

86、<p><b>　　制動釋放時間</b></p><p><b>　　驅動啟動延遲時間</b></p><p><b>　　加速率和減速率</b></p><p>　　躍度（加速率和減速率的變化）</p><p><b>　　例子</b>&l

87、t;/p><p>　　DGC下，具有以下規(guī)格的一個簡單辦公大樓：</p><p>　　需要服務的樓層數(shù)量：16（G，1-15）</p><p>　　行程距離：G/F-15:64米；G/F-1：8米</p><p>　　上方樓層的用戶數(shù)量：1200（每層平均80個人）</p><p>　　需要在5分鐘處理15%</p&

88、gt;<p>　　在輸入所有的CGC和DGC數(shù)據(jù)時，除了每臺電梯往返行程需要服務的平均上方樓層數(shù)目和轎廂平均裝載率會不同外，其他數(shù)據(jù)應該一模一樣。這兩個參數(shù)有所不同的原因如下：</p><p>　　每臺電梯往返行程的平均停層數(shù)目：DGC控制系統(tǒng)致力于平衡同組電梯中每臺電梯的工作量。打個比方說，八臺電梯服務于一個15層的辦公樓，控制系統(tǒng)會理想化的分配每臺電梯往返行程的平均停層次數(shù)為：15層∕8臺電梯=

89、1.875次（完全停止時停在地面層）。如果換成六臺電梯的電梯組，理想情況下控制系統(tǒng)分配的每臺電梯往返行程的平均裝載量為：15層∕6臺電梯=2.5次（見表一）。然而為了得出一個合理的結果，我們把表一的停層次數(shù)加上0.5并把結果轉化成下一個整數(shù)。因此，八臺電梯組成的電梯組中的每臺電梯往返行程中停層數(shù)目是三次（1.875+0.5并轉化成下一個整數(shù)），六臺電梯組成的電梯組中的每臺電梯往返行程中停層數(shù)目是四次（1.875+0.5并轉化成下一個整數(shù)

90、），完全停止時都停在地面層。</p><p>　　表一：上行高峰時理想分配負載量下具有目標控制能力電梯的典型作業(yè)方式。表中為六臺電梯在每個往返行程中平均服務2.5個上方樓層。</p><p>　　轎廂平均裝載率：經(jīng)驗顯示，CGC轎廂會比DGC轎廂更擁擠。我們假設CGC例子中的轎廂平均裝載率為70%；DGC例子中的轎廂平均裝載率為60%。當然不同國家的轎廂平均裝載率也不同，亞洲的轎廂平均裝載

91、率就比歐洲的高，這是因為每個地方人種的平均尺寸不同，文化也不一樣。我們先分析CGC電梯組的運輸性能：</p><p>　　輸入DGC所需的數(shù)據(jù)</p><p>　　DGC情況下，除了每個電梯需要服務的樓層數(shù)目（每個往返行程）和平均轎廂裝載率，我們輸入跟上面CGC一樣的數(shù)據(jù)。我們首先定義平均停層數(shù)目必須是在一個電梯完成每個往返行程后才計數(shù)。每個往返行程的平均停層數(shù)目與涉及的電梯數(shù)量有關。由于

92、使用DGC系統(tǒng)的電梯數(shù)量比較少，所以我們在這里聲明停層數(shù)目（不包括地面層）是基于一些較小規(guī)模轎廂組的，以便檢查他們的運輸性能。即：</p><p>　　8個電梯時：每個往返行程的停層數(shù)目為3（15層∕8個電梯﹢0.5，化為下一個整數(shù)）</p><p>　　7個電梯時：每個往返行程的停層數(shù)目為3</p><p>　　6個電梯時：每個往返行程的停層數(shù)目為4</p&

93、gt;<p>　　5個電梯時：每個往返行程的停層數(shù)目為4</p><p>　　在分析結果中我們還不能確定停層數(shù)目（上方樓層），這是因為我們還不知道電梯的數(shù)量。舉個例子，以容量處理能力和所需電梯數(shù)量為依據(jù)來判斷三個上方樓層所需要的電梯數(shù)量。如果結果顯示七、八個電梯組成的電梯組能達到規(guī)定的15%容量處理能力，那么這個電梯組是適用于三個上方樓層這種情況的。另一方面，如果容量處理能力遠遠高于目標所需的15%

94、，這時就需要減少電梯的數(shù)量，并重新開始分析（上面例子中四個或四個以上的上方樓層將不屬于這種情況）。表二分別顯示了8,7,6和5個電梯組成的電梯組對應服務于3,3,4和4個樓層時的運輸能力。</p><p>　　上面表格中八臺和七臺，六臺和五臺電梯的RTT值相同的原因是他們各自的服務樓層數(shù)目是相同的。這個例子的結果表明DGC只需要六臺電梯來達到15%的容量處理能力,而CGC卻需要八臺。</p><

95、;p><b>　　值得關注的幾點</b></p><p>　　使用相同的軟件來比較DGC和CGC的運輸性能可以輸出準確有用的結果，這時因為變量只有每個往返行程的停層數(shù)目和轎廂裝載率。上面這種用于描述DGC運輸分析的簡便方法所產(chǎn)生的結果是不準確的，如果要進一步比較DGC和CGC運輸性能的不同。還需要謹慎考慮以下因素：</p><p>　　理想情況下每個往返行程的平

96、均停層數(shù)目需要加0.5后轉化成下一個整數(shù)。</p><p>　　在這個方法中我們使用了整個行程長度來計算RTT，然而一般電梯不需要運行整個長度。當然了，為了服務包括頂層在內的所有樓層，一些轎廂也可能要從更低的樓層返回至主要的樓梯平臺，所有這些都是控制系統(tǒng)的算法決定的，而算法就是用來減少平均行程距離的。</p><p>　　隨著每個往返行程停層數(shù)目的減少，同一時間內將允許更多的乘客進出轎廂，

97、乘客的行程變得更有效率，傳送乘客的時間也會因此減少。</p><p>　　轎廂裝載率的減少（相比于CGC）</p><p>　　由于CGC上行高峰的電梯空閑率低于下行高峰的電梯空閑率，所以所需電梯數(shù)量也必須由上行高峰的標準來決定。這樣一來電梯在下行高峰一定存在過載，這就要求控制系統(tǒng)具有更高的裝載處理能力。這是因為在CGC上行高峰時，轎廂隨機的裝滿了不同目的地的乘客。而下行高峰就不存在這種境

98、況，這是因為大部分情況下所有下行高峰的乘客都是為了到達同一目的地（主要入口）。在下行高峰中，轎廂通常只需要停兩到三次就將滿載開往主要入口，基本上與DGC系統(tǒng)的上行高峰RTT值相同，轎廂在一個往返行程中將只停留于二、三或四個上方樓層。</p><p>　　DGC也被叫做上行高峰助推器，這種說法相當正確，因為DGC減少了每個往返行程的停層數(shù)目，顯著提高了上行高峰的運輸性能。也有人說DGC將電梯上行高峰的運輸性能變得和

99、下行高峰的運輸性能一樣好，均衡了電梯的利用率。這是因為DGC可以很好的避免CGC上下行高峰運輸性能固定存在的差異，讓上行高峰RTT值減少到于下行高峰RTT值差不多，電梯性能大大提高，大多數(shù)情況下還能減少所需電梯的實際數(shù)目。</p><p>　　當然還需要考慮雙向行車情況，這是一種要求最苛刻的電梯系統(tǒng)。在一個辦公樓里，雙向行車一般發(fā)生于工作時間和午餐時間，合理的存在于某些場合且不引人注意。而且一些特殊功能的樓層可能

100、引發(fā)嚴重的雙向行車，例如餐飲樓層或會議樓層等，因為這些特殊樓層一般也有電梯服務，也有電梯通往大樓的其他樓層。這種混亂的交通需求可能嚴重干擾電梯組的服務。而解決這個問題的最好方法則是獨立出專門的電梯給特殊功能樓層服務，并將這些樓層盡可能的布置在能被其他電梯服務到的樓房位置里。大部分情況下單獨的電梯服務是不現(xiàn)實的，因為需要先進行電梯的運輸性能評估，然后才能尋找出一個能達到預期水平的，且能解決雙向行車提議的垂直交通系統(tǒng)的方案。實際情況下控制系

101、統(tǒng)還需要在電梯用戶進入轎廂前提前知曉他們想去哪里，相比于CGC，DGC更可能組織出能應付這種混亂的交通運輸?shù)挠行У姆绞絹怼?lt;/p><p>　　因DGC其自身的特性優(yōu)點，相比于CGC，DGC讓更多的樓層更經(jīng)濟合理的被裝載進同樣的區(qū)域。這可以體現(xiàn)在一個有結果的例子里：一個辦公樓在使用CGC情況下確實需要八臺電梯，但如果使用DGC，卻只需要六臺電梯就能實現(xiàn)15%的裝載率要求。現(xiàn)在如果有人將原來的八臺電梯從CGC系統(tǒng)更