首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
All competitive ski and snowboarding events now take place largely on man-made snow. Unlike its natural counterpart, the machine
All competitive ski and snowboarding events now take place largely on man-made snow. Unlike its natural counterpart, the machine
admin
2013-07-20
59
问题
All competitive ski and snowboarding events now take place largely on man-made snow. Unlike its natural counterpart, the machine-made white stuff can be carefully tweaked to make a more durable and consistent surface: one perfect for record-breaking attempts. Snow-making equipment is viewed as essential in most ski areas to guarantee coverage throughout the season. Nowadays, "natural snow is a bonus," says Rich Brown of snow-making technology company York Snow in Victor, New York.
The snow "cannons" or "guns" that manufacture snow mimic the natural formation of snowflakes. Snow machines typically force pressurized water through a nozzle (喷嘴), breaking it into a mist of tiny droplets, and then use compressed air or fans to blast them into the air. As the droplets cool, the molecules line, and crystallize into ice particles. The art to snow-making is adjusting the water and air to ensure that the water drops are small enough and sent far enough that they will freeze before they hit the ground. If the air temperature is quite high, for example, dropping the water content and upping the air would create smaller particles that are more likely to freeze. Snow-making machines also frequently incorporate nucleating agents (成核剂)in the water: small quantities of materials such as bacterial protein, on to which the water molecules attach and freeze. By triggering freezing, these agents raise the temperature at which snow can be made.
Many resorts now use sophisticated computer systems that automatically adjust the air and water output from snow machines based on air temperature, humidity and wind, says Brown. For race courses, experts adjust man-made snow to create a tough, fast and icy course rather than a powdery one. A ski course is also heavily groomed and often intentionally flooded to create patches of ice; these factors generally determine the speed of a race.
Snow manufacturing is in great demand. Some predict that the need for snow will rocket with, the warming effects of climate change, which are already pushing snow lines up the Alps. But this comes with environmental costs, says Michel Revaz, of the International Commission for Protection of the Alps (ICPRA). Making snow chews up energy and water, and can rob rivers and creeks in the surrounding ecosystems. One way to conserve the mountain environment, Revaz says, would be to reuse winter sports competition facilities rather than building new ones.
According to Brown, sophisticated computer systems are used to adjust the air and water based on______.
选项
答案
air temperature,humidity and wind
解析
信息明示题。本题考查滑雪胜地利用计算机调节空气和水流,从而实现人工造雪的依据。定位句提到,Brown介绍说,电脑能根据气温、湿度和风力风向来自动调节空气和水流,进行人工造雪,故答案为airtemperature,humidity and wind。
转载请注明原文地址:https://kaotiyun.com/show/k7n7777K
0
大学英语六级
相关试题推荐
Smokingisverypopularwithpeople.【C1】______ofthesmokersbelievethatsmokingcan【C2】______theirnerveshardenedwithsoci
Smokingisverypopularwithpeople.【C1】______ofthesmokersbelievethatsmokingcan【C2】______theirnerveshardenedwithsoci
TheBushadministrationisgivingpublicschooldistrictsbroadnewlatitudetoexpandthenumberofsingle-sexclasses,andeve
A、Russianhasanobligatoryforgender.B、Russianhasfewergrammarrules.C、Russianhasdifferentsentencestructures.D、Russia
A、Theysmiletocoverembarrassment.B、Itisanunusualandevensuspiciousbehavior.C、Theysmitetoshowpoliteness.D、Itisa
Occasionalself-medicationhasalwaysbeenpartofnormalliving.Themakingandsellingofdrugshasalonghistoryandisclos
A、Toestimatetheextremeweather.B、Todevelopthesatellitetechnology.C、Toimproveagriculturaloutput.D、Tolearnhowtoch
A、Anallergytoanimals.B、Areactiontotoxicchemicals.C、Anallergytofood.D、Contactwithanoxiousplant.D细节题。男士反问女士Yout
ThewaysBushesworkedandlivedinWhiteHouseareunlikethoseoftheClintons.Laura’sdaughterJennahasgotaPh.D.degre
Ifastrangercameuptoyouonthestreet,wouldyougivehimyourname,SocialSecuritynumberande-mailaddress?Probablyno
随机试题
下列哪些可见于肺炎链球菌肺炎患者
男性40岁,1周前干咳左胸痛,近2日来,畏寒发热38.8℃,气急乏力。体检:心率94次/分,律齐,左胸廓饱满,呼吸运动减弱,左下叩之浊音至实音,语颤减低,呼吸音明显减低。经检查诊断明确后,所给予的下列治疗中哪一项是错误的
患者,女,26岁。产后18小时,突然发生阴道大量出血,色鲜红,头晕目花,心悸怔忡,肢冷汗出,面色苍白;舌淡,脉虚数。下列有关该病的西医治法,说法错误的是
丁公司欠甲公司100万元。2005年10月,甲公司与丙公司签订协议,约定甲公司对丁公司的100万元债权由丙公司享有,但未通知丁公司。同年12月,丙公司向法院起诉丁公司要求归还欠款,有关该案的表达正确的是:()
项目风险的分解途径不包括()。
民用住宅楼梯的坡度范围,宜在()之间。
在临时用地指标中,要求平面布置合理、紧凑,在满足环境、职业健康与安全及文明施工要求的前提下尽可能减少废弃地和死角,临时设施占地面积有效利用率大于()。
简述蒙古统一与元朝建立的经过。
(),对公安工作和队伍建设提出了新的挑战,公安工作和公安队伍建设存在的突出问题迫切需要抓紧解决,这是当前加强正规化建设、明确现阶段新的管理标准的出发点和立足点。
Standingupstraightandkeepingyourbodycenteredmayseemlikesecondnaturetomostofus.Butforpeoplewithbalancedisor
最新回复
(
0
)