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2. Exercise sheet: SQL, conceptual and formal design

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10 pages
  • cours magistral
  • cours magistral - matière potentielle : hall
Universität Freiburg Georges-Köhler Allee, Geb. 51 Institut für Informatik D-79110 Freiburg Prof. Dr. G. Lausen Lecture Hall Exercises Databases and Information Systems Winterterm 2011/2012 13.1.2012 2. Exercise sheet: SQL, conceptual and formal design Exercise 1 Let be given the following relation schemata: Produkt(PNr, Gesamtgewicht) PT(PNr, TNr, Anzahl) Teil(TNr, Bezeichnung, Gewicht) Schema PT specifies, which parts contribute to a respective product and in which number this is done.
  • lname- values of the respective countries
  • procedure erreichbarvon
  • tables t1
  • value of a tuple
  • referential action
  • table definition
  • sql query
  • b.lcode2
  • value
  • end
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CoralReefConservation
CoralReefBiology|ssonLenalP  
CORALREEFCONSERVATIONLESSONPLAN AReefofYourOwn
Theme CoralReefBiology
LinkstoOverviewEssaysandResourcesNeededforStudent  Research http://oceanservice.noaa.gov/topics/ocean/coralreefs http://www.coris.noaa.gov/about/biology http://oceanservice.noaa.gov/education/kits/corals/coral01_intro.html
SubjectArea LifeScience
GradeLevel 9-12
FocusQuestion Whatphysiological,ecological,andbehavioralstrategiescon tributetothesuccessofreef-buildingcorals?
LearningObjectives  anrtpoimcercseebielbdotnaiethdanplextSillbeaudentsw ofasexualandsexualreproductivestrategiestoreef-building corals.
ianhwysiitmibeabletoexplSedutstnlliwtahttnatrop reef-buildingcoralshaveanutritionalstrategythatincludes bothphotosynthesisandcarnivory.
wdielslcrbiebSatbuldeenttsoahivrosewtoebf-attheer buildingcoralsusetocompeteforlivingspacewithother species.  
ebaeltoxelpianhowcoralreefacsrpncudoeblliwstnedutS  highlevelsofbiologicalmaterialwhenthewaterssurround ingthesereefscontainrelativelysmallamountsofthenutri entsnormallyneededtosupportbiologicalproduction.
oceanservice.noaa.gov/education
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CoralReefBiology|laPonssLen
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CoralReefConservation
MaterialsNeeded feSflCTo-psieest(ofifeitherCoralRee-illthn-ble-kan version,withorwithoutwordbank)orCoralReefSelf-TestCrosswordPuzzle,onecopyforeachstudentorstu-dentgroup,availableat:http://oceanservice.noaa.gov/education/ kits/corals/lessons/coral_bleach.pdf opt(onaioC)lupmosrettiwhinternetacces;siftsdunestd  nothaveaccesstotheinternet,directthemtolocallibrary  resources,and/ordownloadcopiesofmaterialscitedunder  “LearningerudecorPpicoeidovprdanametseefhtseosrial toeachstudentorstudentgroup
Audio/VisualMaterialsNeeded None
TeachingTime Twoorthree45-minuteclassperiods,plustimeforstudent  research;additionaltimewillbeneededifyoudecidetoset upamodelcoralreefecosystem
SeatingArrangement  Groupsof3-4students
MaximumNumberofStudents 30
KeyWords  Coralreefs Aquarium Symbiosis Zooxanthellae Broadcastspawning
  BackgroundInformation Coralreefsareamongthemostbiologicallydiverseandpro ductiveecosystemsonEarth.Coralreefsprotectshorelines  fromerosionandstormdamage,supplyfoodsthatareimpor tanttomanycoastalcommunities,andproviderecreational  andeconomicopportunities.Inaddition,thehighlydiverse  biologicalcommunitiesassociatedwithcoralreefsarenew  sourcesofpowerfulantibiotic,anti-cancerandanti-inflamma torydrugsthathavethepotentialtobenefittheentirehuman  
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oceanservice.noaa.gov/edu
CoralReefConservation
CoralReefBiology|LenlaPonss
race(formoreinformationondrugsfromcoralreefs,visithttp: //oceanservice.noaa.gov/education/corals/lessons/coral_bleach.pdfdna http://oceanexplorer.noaa.gov/explorations/03bio/background/edu/ edu.html).
Unfortunately,coralreefsareregularlydamagedbyavariety  ofnaturalstresses.Hurricanesandcyclonescanbreakcorals  looseandscatterthemintoareaswheretheycannotsurvive.  Stormdamagetocoastalareascanincreasetheinflowofsedi mentsthatcansmotherlivingreefsandreducelightneeded  bymanyshallow-watercorals.Freshwaterrunoffmaycause  additionalstressbyloweringthesalinityofwatersurround ingreefs.Unusuallylowtidescanleavecoralsexposedtohigh  temperatures,solarradiation,andtheriskofdryingout.High  temperaturesassociatedwithphenomenasuchasElNinoand prolongedperiodsofunusualwarmthcauseseveredamage  throughthermalstressandmaybelethal.Coralsarealsosub jecttopredationanddisease.Coralreefshavesurvivedthese  typesofthreatsformillionsofyears.Somereefshavebecome  extinct,butothershaveflourished.  
Coralsarealsothreatenedbyhumanactivities.Thesestresses  mayhaveamuchgreaterimpactthannaturalstresses.Sewage  andchemicalpollutioncancauseovergrowthsofalgae,oxygen  depletion,andpoisoning.Poorlandmanagementanddefores tationcanleadtoexcessiverunoffandsedimentation.Fishing  withheavytrawls,poisons,andexplosivesdamagesthephysi calstructureofreefsaswellasthecoralanimalsthatbuildthem.  Carelesstourists,boatanchors,andcollectionfortheaquarium  tradealsocausemechanicaldamage.Thermalpollutionfrom  powerplantsandotherhumanactivitiesthatraisewatertem peraturescausephysiologicalstressthatkillscoralanimalsand  leavesthereefstructurevulnerabletoerosion.Oilspills,fuel  discharges,andanti-foulingchemicalsfromboatsaddadditional  stress.Manyoftheseimpactsaretheresultofignorance;people  simplyarentawareoftheimportanceofcoralreefsorthecon sequencesoftheiractions.Butthedamageandthreatstoreefs  continuestoincreaseonaglobalscale.Thereisalsoevidence  thatimpactscausedbyhumansmaybeincreasingtheseverity  ofnaturalthreats.Manyresearchershavenoticedanincreasein  coraldiseasesandbelievethatatleastpartofthereasonisthat  thecoralshavebeenweakenedbyotherstressfactors.
oceanservice.noaa.gov/education
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