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日期:2020-03-24 11:14

Assignment 3

Due on March 30th, 2020

COMP 8042

All work should be done individually.

Geographic Information System

Geographic information systems organize information pertaining to geographic features and

provide various kinds of access to the information. A geographic feature may possess many

attributes (see below). In particular, a geographic feature has a specific location. There

are a number of ways to specify location. For this project, we will use latitude and longitude,

which will allow us to deal with geographic features at any location on Earth. A

reasonably detailed tutorial on latitude and longitude can be found in the Wikipedia at

http://en.wikipedia.org/wiki/Latitude and http://en.wikipedia.org/wiki/Longitude.

The GIS record files were obtained from the website for the USGS Board on Geographic

Names (http://geonames.usgs.gov). The file begins with a descriptive header line, followed

by a sequence of GIS records, one per line, which contain the fields provide in Table 1 in

Appendix in the indicated order.

Notes:

? See https://geonames.usgs.gov/domestic/states fileformat.htm for the full field descriptions.

? The type specifications used here have been modified from the source (URL above) to

better reflect the realities of your programming environment.

? Latitude and longitude may be expressed in DMS (degrees/minutes/seconds, 0820830W)

format, or DEC (real number, -82.1417975) format. In DMS format, latitude will always

be expressed using 6 digits followed by a single character specifying the hemisphere, and

longitude will always be expressed using 7 digits followed by a hemisphere designator.

? Although some fields are mandatory, some may be omitted altogether. Best practice is

to treat every field as if it may be left unspecified. Certain fields are necessary in order

to index a record: the feature name and the primary latitude and primary longitude.

If a record omits any of those fields, you may discard the record, or index it as far as

possible.

In the GIS record file, each record will occur on a single line, and the fields will be separated

by pipe (‘|’) symbols. Empty fields will be indicated by a pair of pipe symbols with no

characters between them. See the posted VA Monterey.txt file for many examples.

GIS record files are guaranteed to conform to this syntax, so there is no explicit requirement

that you validate the files. On the other hand, some error-checking during parsing may help

you detect errors in your parsing logic.

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Assignment 3

Due on March 30th, 2020

COMP 8042

Hassan S. Shavarani

The file can be thought of as a sequence of bytes, each at a unique offset from the beginning

of the file, just like the cells of an array. So, each GIS record begins at a unique offset from

the beginning of the file.

Line Termination

Each line of a text file ends with a particular marker (known as the line terminator). In

MS-DOS/Windows file systems, the line terminator is a sequence of two ASCII characters

(CR + LF, 0X0D0A). In Unix systems, the line terminator is a single ASCII character (LF).

Other systems may use other line termination conventions.

Why should you care? Which line termination is used has an effect on the file offsets for all

but the first record in the data file. As long as were all testing with files that use the same

line termination, we should all get the same file offsets. But if you change the file format (of

the posted data files) to use different line termination, you will get different file offsets than

are shown in the posted log files. Most good text editors will tell you what line termination

is used in an opened file, and also let you change the line termination scheme.

In Figure 1, note that some record fields are optional, and that when there is no given value

for a field, there are still delimiter symbols for it.

Also, some of the lines are “wrapped” to fit into the text box; lines are never “wrapped” in

the actual data files.

Figure 1: Sample Geographic Data Records

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Assignment 3

Due on March 30th, 2020

COMP 8042

Hassan S. Shavarani

Assignment

You will implement a system that indexes and provides search features for a file of GIS

records, as described above.

Your system will build and maintain several in-memory index data structures to support

these operations:

? Importing new GIS records into the database file

? Retrieving data for all GIS records matching given geographic coordinates

? Retrieving data for all GIS records matching a given feature name and state

? Retrieving data for all GIS records that fall within a given (rectangular) geographic

region

? Displaying the in-memory indices in a human-readable manner

You will implement a single software system in C++ to perform all system functions.

Program Invocation

The program will take the names of three files from the command line, like this:

./GIS <database file name> <command script file name> <log file name>

Note that this implies your main class must be named GIS, and be able to be compiled

simply using a g++ compile command. Preferably, you are encouraged to create make files

for the project and provide the required dependency files in your submission.

The database file should be created as an empty file; note that the specified database file may

already exist, in which case the existing file should be truncated or deleted and recreated.

If the command script file is not found the program should write an error message to the

console and exit. The log file should be rewritten every time the program is run, so if the file

already exists it should be truncated or deleted and recreated.

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Assignment 3

Due on March 30th, 2020

COMP 8042

Hassan S. Shavarani

System Overview

The system will create and maintain a GIS database file that contains all the records that

are imported as the program runs. The GIS database file will be empty initially. All the

indexing of records will be done relative to this file.

There is no guarantee that the GIS record file will not contain two or more distinct records

that have the same geographic coordinates. In fact, this is natural since the coordinates are

expressed in the usual DMS system. So, we cannot treat geographic coordinates as a primary

(unique) key.

The GIS records will be indexed by the Feature Name and State (abbreviation) fields. This

name index will support finding offsets of GIS records that match a given feature name and

state abbreviation.

The GIS records will also be indexed by geographic coordinate. This coordinate index will

support finding offsets of GIS records that match a given primary latitude and primary

longitude.

The system will include a buffer pool, as a front end for the GIS database file, to improve

search speed. See the discussion of the buffer pool below for detailed requirements. When

performing searches, retrieving a GIS record from the database file must be managed through

the buffer pool. During an import operation, when records are written to the database file,

the buffer pool will be bypassed, since the buffer pool would not improve performance during

imports.

When searches are performed, complete GIS records will be retrieved from the GIS database

file that your program maintains. The only complete GIS records that are stored in memory

at any time are those that have just been retrieved to satisfy the current search, or individual

GIS records created while importing data or GIS records stored in the buffer pool.

Aside from where specific data structures are required, you may use any suitable STL library

implementation you like.

Each index should have the ability to write a nicely-formatted display of itself to an output

stream.

Name Index Internals

The name index will use a hash table for its physical organization. Each hash table entry

will store a feature name and state abbreviation (separately or concatenated, as you like)

and the file offset(s) of the matching record(s). Since each GIS record occupies one line in

the file, it is a trivial matter to locate and read a record given nothing but the file offset at

which the record begins.

Your table will use quadratic probing to resolve collisions, with the quadratic function (n

2+n)

2

to compute the step size.

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Assignment 3

Due on March 30th, 2020

COMP 8042

Hassan S. Shavarani

The hash table must use a contiguous physical structure (array). The initial size of the table

will be 1024, and the table will resize itself automatically, by doubling its size whenever the

table becomes 70% full.

Since the specified table sizes given above are powers of 2, an empty slot will always be found

unless the table is full.

You can use your desired hash function (e.g. elfhash), and apply it to the concatenation of

the feature name and state (abbreviation) field of the data records. Precisely how you form

the concatenation is up to you.

You must be able to display the contents of the hash table in a readable manner.

Coordinate Index Internals

The coordinate index will use a bucket PR quadtree for the physical organization. In a bucket

PR quadtree, each leaf stores up to K data objects (for some fixed value of K). Upon insertion,

if the added value would fall into a leaf that is already full, then the region corresponding

to the leaf will be partitioned into quadrants and the K+1 data objects will be inserted into

those quadrants as appropriate. As is the case with the regular PR quadtree, this may lead

to a sequence of partitioning steps, extending the relevant branch of the quadtree by multiple

levels. In this project, K will probably equal 4, but I reserve the right to specify a different

bucket size with little notice, so this should be easy to modify.

The index entries held in the quadtree will store a geographic coordinate and a collection of

the file offsets of the matching GIS records in the database file.

Note: do not confuse the bucket size with any limit on the number of GIS records that may

be associated with a single geographic coordinate. A quadtree node can contain index objects

for up to K different geographic coordinates. Each such index object can contain references

to an unlimited number of different GIS records.

The PR quadtree implementation should follow good design practices, and its interface should

be somewhat similar to that of the BST. You are expected to implement different types for

the leaf and internal nodes, with appropriate data membership for each, and an abstract base

type from which they are both derived.

You must be able to display the PR quadtree in a readable manner. The display must clearly

indicate the structure of the tree, the relationships between its nodes, and the data objects

in the leaf nodes.

Buffer Pool Details

The buffer pool for the database file should be capable of buffering up to 15 records, and

will use LRU replacement. You may use any structure you like to organize the pool slots;

however, since the pool will have to deal with record replacements, some structures will be

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Assignment 3

Due on March 30th, 2020

COMP 8042

Hassan S. Shavarani

more efficient (and simpler) to use. You may use any classes from STL library you think are

appropriate.

It is up to you to decide whether your buffer pool stores interpreted or raw data; i.e., whether

the buffer pool stores GIS record objects or just strings.

You must be able to display the contents of the buffer pool, listed from MRU to LRU entry,

in a readable manner. The order in which you retrieve records when servicing a multi-match

search is not specified, so such searches may result in different orderings of the records within

the buffer pool. That is OK.

A Note on Coordinates and Spatial Regions

It is important to remember that there are fundamental differences between the notion that

a geographic feature has specific coordinates (which may be thought of as a point) and the

notion that each node of the PR quadtree corresponds to a particular sub-region of the

coordinate space (which may contain many geographic features).

In this assignment, coordinates of geographic features are specified as latitude/longitude

pairs, and the minimum resolution is one second of arc. Thus, you may think of the geographic

coordinates as being specified by a pair of integer values.

On the other hand, the boundaries of the sub-regions are determined by performing arithmetic

operations, including division, starting with the values that define the boundaries of the

world. Unless the dimensions of the world happen to be powers of 2, this can quickly lead

to regions whose boundaries cannot be expressed exactly as integer values. You may use

floating-point values or integer values to represent region boundaries when computing region

boundaries during splitting and quadtree traversals. If you use integers, be careful not to

unintentionally create “gaps” between regions.

Your implementation should view the boundary between regions as belonging to one of those

regions. The choice of a particular rule for handling this situation is left to you.

When carrying out a region search, you must determine whether the search region overlaps

with the region corresponding to a subtree node before descending into that subtree. You

may define a Rectangle class which could be (too) useful.

Other System Elements

There should be an overall controller that validates the command line arguments and manages

the initialization of the various system components. The controller should hand off execution

to a command processor that manages retrieving commands from the script file, and making

the necessary calls to other components in order to carry out those commands.

Naturally, there should be a data type that models a GIS record.

There may well be additional system elements, whether data types or data structures, or

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Assignment 3

Due on March 30th, 2020

COMP 8042

Hassan S. Shavarani

system components that are not mentioned here. The fact no additional elements are explicitly

identified here does not imply that you will not be expected to analyze the design issues

carefully, and to perhaps include such elements.

Aside from the command-line interface, there are no specific requirements for interfaces of

any of the classes that will make up your GIS; it is up to you to analyze the specification

and come up with an appropriate set of classes, and to design their interfaces to facilitate the

necessary interactions. It is probably worth pointing out that an index (e.g., a geographic

coordinate index) should not simply be a naked container object (e.g, quadtree); if that’s not

clear to you, think more carefully about what sort of interface would be appropriate for an

index, as opposed to a container.

Command File

The execution of the program will be driven by a script file. Lines beginning with a semicolon

character (‘;’) are comments and should be ignored. Blank lines are possible. Each line in

the command file consists of a sequence of tokens, which will be separated by single tab

characters. A line terminator will immediately follow the final token on each line. The

command file is guaranteed to conform to this specification, so you do not need to worry

about error-checking when reading it.

The first non-comment line will specify the world boundaries to be used:

world<tab><westLong><tab><eastLong><tab><southLat><tab><northLat>

This will be the first command in the file, and will occur once. It specifies the

boundaries of the coordinate space to be modeled. The four parameters will be

longitude and latitudes expressed in DMS format, representing the vertical and

horizontal boundaries of the coordinate space.

It is certainly possible that the GIS record file will contain records for features

that lie outside the specified coordinate space. Such records should be ignored;

i.e., they will not be indexed.

Each subsequent non-comment line of the command file will specify one of the commands

described below. One command is used to load records into your database from external

files:

import<tab><GIS record file>

Add all the valid GIS records in the specified file to the database file. This means

that the records will be appended to the existing database file, and that those

records will be indexed in the manner described earlier. When the import is

completed, log the number of entries added to each index, and the longest probe

sequence that was needed when inserting to the hash table. (A valid record is one

that lies within the specified world boundaries.)

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Assignment 3

Due on March 30th, 2020

COMP 8042

Hassan S. Shavarani

Another command requires producing a human-friendly display of the contents of an index

structure:

debug<tab>[ quad | hash | pool ]

Log the contents of the specified index structure in a fashion that makes the

internal structure and contents of the index clear. It is not necessary to be overly

verbose here, but you should include information like key values and file offsets

where appropriate.

Another simply terminates execution, which is handy if you want to process only part of a

command file:

quit<tab>

Terminate program execution.

The other commands involve searches of the indexed records:

what is at<tab><geographic coordinate>

For every GIS record in the database file that matches the given <geographic

coordinate>, log the offset at which the record was found, and the feature name,

county name, and state abbreviation. Do not log any other data from the matching

records.

what is<tab><feature name><tab><state abbreviation>

For every GIS record in the database file that matches the given <feature name>

and <state abbreviation>, log the offset at which the record was found, and

the county name, the primary latitude, and the primary longitude. Do not log

any other data from the matching records.

what is in<tab><geographic coordinate><tab><half-height><tab><half-width>

For every GIS record in the database file whose coordinates fall within the closed

rectangle with the specified height and width, centered at the <geographic coordinate>,

log the offset at which the record was found, and the feature name, the state name,

and the primary latitude and primary longitude. Do not log any other data from

the matching records. The half-height and half-width are specified as seconds.

The what is in command takes an optional modifier, -long, which causes the

display of a long listing of the relevant records. The switch will be the first token

following the name of the command. If this switch is present, then for every GIS

record in the database file whose coordinates fall within the closed rectangle with

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Assignment 3

Due on March 30th, 2020

COMP 8042

Hassan S. Shavarani

the specified height and width, centered at the <geographic coordinate>, log

every important non-empty field, nicely formatted and labeled. See the posted log

files for an example. Do not log any empty fields. The half-height and half-width

are specified as seconds.

The what is in command also takes an optional modifier, causing the search results

to be filtered:

-filter [ pop | water | structure ]

The switch and its modifier will be the first and second tokens following the name

of the command. If present, this causes the set of matching records to be filtered

to only show those whose feature type field corresponds to the given filter specifier.

See Table 2 in the Appendix for instructions on how to interpret the feature types

shown above.

If a <geographic coordinate> is specified for a command, it will be expressed as a pair of

latitude/longitude values, expressed in the same DMS format that is used in the GIS record

files.

For all the commands, if a search results in displaying information about multiple records,

you have to use a sort algorithm to show them in a sorted manner, the choice of sort algorithm

and feature to perform the sort on, is up to you. Optionally you can receive the sort algorithm

name (in case you have implemented multiple) and the feature to perform the sort on with

an argument immediately after the other switch/modifier pair(s) if any available. Make sure

you mention the implemented sort algorithm and discuss its performance in your final report.

Sample command scripts, and corresponding log files, are provided alongside this description

file. As a general rule, every command should result in some output. In particular, a

descriptive message should be logged if a search yields no matching records.

Log File Description

Your output should be clear, concise, well labeled, and correct. You should begin the log

with a few lines identifying yourself, and listing the names of the input files that are being

used.

The remainder of the log file output should come directly from your processing of the command

file. You are required to echo each comment line, and each command that you process

to the log file so that it’s easy to determine which command each section of your output

corresponds to. Each command (except for “world”) should be numbered, starting with 1,

and the output from each command should be well formatted, and delimited from the output

resulting from processing other commands.

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Assignment 3

Due on March 30th, 2020

COMP 8042

Hassan S. Shavarani

Submission

For this assignment, you must submit an archive (zip or tar) file containing all the source

code files for your implementation (i.e., .cpp files). Submit only the source files. Do not

submit the compiled files or any of object files. If you use packages in your implementation

(and that’s good practice), your archive file must include the correct directory structure for

those packages, and your GIS.cpp file must be in the top directory when the archive file is

unpacked. Your code must be ready to compile using g++ -std=c++11 or a simple

Makefile if you have a more complicated structure. Make sure no visual studio related

dependencies or solution files are there when submitting the result, since I certainly will not

use visual studio to test and grade your project.

Alongside your source files, I need a pdf file describing your solution, general architecture of

your code, and the list of data structures you have implemented or used from STL. Run one

of the scripts and put a screen shot of that run in your report, as well.

The correctness of your solution will be evaluated by executing your solution on a collection

of test data files. Be sure to test your solution with all of the data sets that are posted, since

I will use a variety of data sets, including at least one very large data one (perhaps hundreds

of thousands of records) in my evaluation.

As it is stated in the beginning of the file description this project must be done individually.

You are not allowed to copy a single function from another person nor from the

internet without citing them. You may use any of the previously provided lab source

codes completed by yourself to reduce the implementation time of this assignment

(don’t forget to mention which lab codes you have used in your final report).

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Assignment 3

Due on March 30th, 2020

COMP 8042

Hassan S. Shavarani

Appendix

Table 1: Geographic Data Record Format

Name Type Length/

Decimals Short Description

Feature ID Integer 10 Permanent, unique feature record identifier

and official feature nameFeature Name String 120

Feature Class String 50 See Table 2 later in this specification

State

Alpha String 2 The unique two letter alphabetic code

and the unique two number code for a US State

State

Numeric String 2

Country

Name String 100 The name and unique three number code

for a county or county equivalent County

Numeric String 3

Primary

Latitude

DMS String 7 The official feature location

DMS-degrees/minutes/seconds

DEC-decimal degrees

Note: Records showing “Unknown” and zeros for

the latitude and longitude DMS and decimal fields,

respectively, indicate that the coordinates of the

feature are unknown. They are recorded in the

database as zeros to satisfy the format requirements

of a numerical data type. They are not errors and

do not reference the actual geographic coordinates

at 0 latitude, 0 longitude.

Primary

Longitude

DMS String 8

Primary

Latitude

DEC

Real

Number 11/7

Primary

Longitude

DEC

Real

Number 12/7

Source

Latitude

DMS String 7 Source coordinates of linear feature only

(Class = Stream, Valley, Arroyo)

DMS-degrees/minutes/seconds

DEC-decimal degrees

Note: Records showing “Unknown” and zeros for

the latitude and longitude DMS and decimal fields,

respectively, indicate that the coordinates of

the feature are unknown. They are recorded in the

database as zeros to satisfy the format requirements

of a numerical data type. They are not errors and

do not reference the actual geographic coordinates

at 0 latitude, 0 longitude.

Source

Longitude

DMS String 8

(meters) Integer 5 Elevation in meters above (-below) sea level

of the surface at the primary coordinates

Elevation

(feet) Integer 6 Elevation in feet above (-below) sea level

of the surface at the primary coordinates

Map Name String 100 Name of USGS base series topographic

map containing the primary coordinates.

Date Created String Date The date the feature was initially

committed to the database.

Date Edited String Date The date any attribute of an existing

feature was last edited.

The Feature Class field of the GIS records may contain any of the following designators. We care

about these because of the -filter switch that may be used with the what is in commands. The

table below indicates which of the standard correspond to one of the filter specifiers.

Table 2: Feature Class Designators

Class Type Description

Airport structure Manmade facility maintained for the use of aircraft

(airfield, airstrip, landing field, landing strip).

Arch Natural arch-like opening in a rock mass

(bridge, natural bridge, sea arch).

Area

Any one of several areally extensive natural features

not included in other categories

(badlands, barren, delta, fan, garden).

Arroyo water Watercourse or channel through which water may

occasionally flow (coulee, draw, gully, wash).

Bar

Natural accumulation of sand, gravel, or alluvium

forming an underwater or exposed embankment

(ledge, reef, sandbar, shoal, spit).

Basin Natural depression or relatively low area enclosed

by higher land (amphitheater, cirque, pit, sink).

Bay water

Indentation of a coastline or shoreline enclosing a

part of a body of water; a body of water partly

surrounded by land

(arm, bight, cove, estuary, gulf, inlet, sound).

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Beach

The sloping shore along a body of water that is

washed by waves or tides and is usually covered

by sand or gravel

(coast, shore, strand).

Bench

Area of relatively level land on the flank of an

elevation such as a hill, ridge, or mountain

where the slope of the land rises on one side

and descends on the opposite side (level).

Bend water

Curve in the course of a stream and (or) the land

within the curve; a curve in a linear body of water

(bottom, loop, meander).

Bridge structure

Manmade structure carrying a trail, road, or other

transportation system across a body of water or

depression (causeway, overpass, trestle).

Building structure

A manmade structure with walls and a roof for

protection of people and (or) materials,

but not including church, hospital, or school.

Canal water

Manmade waterway used by watercraft or for

drainage, irrigation, mining, or water power

(ditch, lateal).

Cape Projection of land extending into a body

of water (lea, neck, peninsula, point).

Cave

Natural underground passageway or chamber,

or a hollowed out cavity in the side of a cliff

(cavern, grotto).

Cemetery A place or area for burying the dead

(burial, burying ground, grave, memorial garden).

Census

A statistical area delineated locally specifically

for the tabulation of Census Bureau data

(census designated place, census county division,

unorganized territory, various types of

American Indian/Alaska Native statistical areas).

Distinct from Civil and Populated Place.

Channel water

Linear deep part of a body of water through

which the main volume of water flows and

is frequently used as aroute for watercraft

(passage, reach, strait, thoroughfare, throughfare).

Church structure Building used for religious worship

(chapel, mosque, synagogue, tabernacle, temple).

Civil

A political division formed for administrative purposes

(borough, county, incorporated place, municipio,

parish, town, township).

Distinct from Census and Populated Place.

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Cliff

Very steep or vertical slope

(bluff, crag, head, headland, nose, palisades,

precipice, promontory, rim, rimrock).

Crater

Circular-shaped depression at the summit of

a volcanic cone or one on the surface of

the land caused by the impact of a meteorite;

a manmade depression caused by an explosion

(caldera, lua).

Crossing

A place where two or more routes of

transportation form a junction or intersection

(overpass, underpass).

Dam structure

Water barrier or embankment built across the

course of a stream or into a body of water to

control and (or) impound the flow of water

(breakwater, dike, jetty).

Falls water Perpendicular or very steep fall of water in

the course of a stream (cascade, cataract, waterfall).

Flat Relative level area within a region of greater relief

(clearing, glade, playa).

Forest

Bounded area of woods, forest, or grassland under

the administration of a political agency (see ”woods”)

(national forest, national grasslands, State forest).

Gap

Low point or opening between hills or mountains or

in a ridge or mountain range

(col, notch, pass, saddle, water gap, wind gap).

Glacier water

Body or stream of ice moving outward and downslope

from an area of accumulation; an area of relatively

permanent snow or ice on the top or side of a mountain

or mountainous area (icefield, ice patch, snow patch).

Gut water Relatively small coastal waterway connecting larger

bodies of water or other waterways (creek, inlet, slough).

Harbor water Sheltered area of water where ships or other watercraft

can anchor or dock (hono, port, roads, roadstead).

Hospital structure Building where the sick or injured may receive medical

or surgical attention (infirmary).

Island

Area of dry or relatively dry land surrounded by water or

low wetland (archipelago, atoll, cay, hammock, hummock,

isla, isle, key, moku, rock).

Isthmus Narrow section of land in a body of water connecting

two larger land areas.

Lake water Natural body of inland water (backwater, lac, lagoon,

laguna, pond, pool, resaca, waterhole).

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Lava Formations resulting from the consolidation of molten rock

on the surface of the Earth (kepula, lava flow).

Levee structure Natural or manmade embankment flanking a stream

(bank, berm).

Locale

Place at which there is or was human activity;

it does not include populated places, mines, and dams

(battlefield, crossroad, camp, farm, ghost town, landing,

railroad siding, ranch, ruins, site, station, windmill).

Military Place or facility used for various aspects of or relating

to military activity.

Mine

Place or area from which commercial minerals are or

were removed from the Earth; not including oilfield

(pit, quarry, shaft).

Oilfield Area where petroleum is or was removed from the Earth.

Park structure

Place or area set aside for recreation or preservation of a

cultural or natural resource and under some form of

government administration; not including National or

State forests or Reserves (national historical landmark,

national park, State park, wilderness area).

Pillar Vertical, standing, often spire-shaped, natural rock formation

(chimney, monument, pinnacle, pohaku, rock tower).

Plain

A region of general uniform slope, comparatively level and

of considerable extent

(grassland, highland, kula, plateau, upland).

Populated

Place pop

Place or area with clustered or scattered buildings and a

permanent human population (city, settlement, town, village).

A populated place is usually not incorporated and by

definition has no legal boundaries. However, a populated

place may have a corresponding ”civil” record, the legal

boundaries of which may or may not coincide with the perceived

populated place. Distinct from Census and Civil classes.

Post Office structure An official facility of the U.S. Postal Service used for processing

and distributing mail and other postal material.

Range Chain of hills or mountains; a somewhat linear,

complex mountainous or hilly area (cordillera, sierra).

Rapids water Fast-flowing section of a stream, often shallow and

with exposed rock or boulders (riffle, ripple).

Reserve A tract of land set aside for a specific use

(does not include forests, civil divisions, parks).

Reservoir water Artificially impounded body of water (lake, tank).

Ridge

Elevation with a narrow, elongated crest which can

be part of a hill or mountain

(crest, cuesta, escarpment, hogback, lae, rim, spur).

15

Name: ..................

Id: A0..............

Assignment 3

Due on March 30th, 2020

COMP 8042

Hassan S. Shavarani

School structure Building or group of buildings used as an institution for study,

teaching, and learning (academy, college, high school, university).

Sea water Large body of salt water (gulf, ocean).

Slope A gently inclined part of the Earth’s surface (grade, pitch).

Spring water Place where underground water flows naturally to

the surface of the Earth (seep).

Stream water

Linear body of water flowing on the Earth’s surface

(anabranch, awawa, bayou, branch, brook, creek,

distributary, fork, kill, pup, rio, river, run, slough).

Summit

Prominent elevation rising above the surrounding level

of the Earth’s surface; does not include pillars, ridges,

or ranges (ahu, berg, bald, butte, cerro, colina, cone,

cumbre, dome, head, hill, horn, knob, knoll, mauna,

mesa, mesita, mound, mount, mountain, peak, puu,

rock, sugarloaf, table, volcano).

Swamp water

Poorly drained wetland, fresh or saltwater, wooded or grassy,

possibly covered with open water

(bog, cienega, marais, marsh, pocosin).

Tower structure A manmade structure, higher than its diameter, generally

used for observation, storage, or electronic transmission.

Trail Route for passage from one point to another; does not

include roads or highways (jeep trail, path, ski trail).

Tunnel structure Linear underground passageway open at both ends.

Unknown This class is assigned to legacy data only.

It will not be assigned to new or edited records.

Valley

Linear depression in the Earth’s surface that generally

slopes from one end to the other (barranca, canyon, chasm,

cove, draw, glen, gorge, gulch, gulf, hollow, ravine).

Well water Manmade shaft or hole in the Earth’s surface used to

obtain fluid or gaseous materials.

Woods

Small area covered with a dense growth of trees;

does not include an area of trees under the administration of a

political agency (see ”forest”).

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