Equation
Properties
Units
Documentation
Annotation
Top-Level Model:
Compost(t)
Compost(t - dt) + (Composting_Waste + Composting_Waste_D) * dt
INIT Compost = 0
Lbs
The quantity of food composted over the course of a year
Donated_Food(t)
Donated_Food(t - dt) + (Leftovers_to_Donation_D + Leftovers_to_Donation) * dt
INIT Donated_Food = 0
Lbs
The quantity of food that is donated outside of the JMU ecosystem over the course of a year.
D Hall Food recovery averages approximately 45 pounds per week.
"Ingredients_D-Hall"(t)
"Ingredients_D-Hall"(t - dt) + (Buying_Ingredients_D + Presemester_order_D - Cooking_D - Spoiling_Ingredients_D) * dt
INIT "Ingredients_D-Hall" = 1000
Lbs
Ingredients bought for cooking at D-Hall.
"Ingredients_E-Hall"(t)
"Ingredients_E-Hall"(t - dt) + (Buying_Ingredients + Presemester_order - Cooking - Spoiling_Ingredients) * dt
INIT "Ingredients_E-Hall" = 1000
Lbs
Ingredients bought for cooking at E-Hall.
Insecure_Students_Eating_from_Pantry(t)
Insecure_Students_Eating_from_Pantry(t - dt) + (Students_to_Pantry - Students_Fed_From_Pantry) * dt
INIT Insecure_Students_Eating_from_Pantry = 0
TRANSIT TIME = 1
CONTINUOUS
ACCEPT MULTIPLE BATCHES
People
Food insecure students that meet needs through the pantry.
CONVEYOR
Insecure_Students_Eating_in_Dining_Hall(t)
Insecure_Students_Eating_in_Dining_Hall(t - dt) + (Insecure_Students_to_Dining_Hall - Insecure_Students_Returning_from_Dining_Hall) * dt
INIT Insecure_Students_Eating_in_Dining_Hall = 0
TRANSIT TIME = 1
CONTINUOUS
ACCEPT MULTIPLE BATCHES
People
Food insecure students that meet needs through the dining halls
CONVEYOR
Insecure_Students_Eating_off_campus(t)
Insecure_Students_Eating_off_campus(t - dt) + (Students_to_Off_Campus - Insecure_Students_Returning_from_Off_Campus) * dt
INIT Insecure_Students_Eating_off_campus = 0
TRANSIT TIME = 1
CONTINUOUS
ACCEPT MULTIPLE BATCHES
People
Food insecure students that meet needs off campus.
CONVEYOR
"Leftover_Food_D-Hall"(t)
"Leftover_Food_D-Hall"(t - dt) + (Creating_Leftover_food_D - Reusing_food_D - Leftovers_to_Pantry_D - Leftovers_to_Donation_D - Leftovers_going_bad_D) * dt
INIT "Leftover_Food_D-Hall" = 500
Lbs
Leftover Food that is still human edible. D-Hall.
"Leftover_Food_E-Hall"(t)
"Leftover_Food_E-Hall"(t - dt) + (Creating_Leftover_food - Reusing_food - Leftovers_to_Pantry - Leftovers_to_Donation - Leftovers_going_bad) * dt
INIT "Leftover_Food_E-Hall" = 500
Lbs
Leftover Food that is still human edible. E-Hall.
Pantry_Stock_of_Food(t)
Pantry_Stock_of_Food(t - dt) + (Leftovers_to_Pantry + Incoming_Pantry_donations_from_Blue_Ridge_Food_Bank + Leftovers_to_Pantry_D - Students_pulling_from_pantry - Pantry_Spoiling) * dt
INIT Pantry_Stock_of_Food = 2000
Lbs
The Lbs. of food present within the JMU pantry.
Perceived_Food_Insecure_Students(t)
Perceived_Food_Insecure_Students(t - dt) + (Food_Insecurity_Initialization + Students_becoming_Food_insecure + Students_Still_Insecure - Students_to_Off_Campus - Students_to_Pantry - Insecure_Students_to_Dining_Hall) * dt
INIT Perceived_Food_Insecure_Students = 0
People
Students who are not consistently meeting needs. Defined as missing meals for non-personal reason more than three times a week.
"Potential_Waste_D-Hall"(t)
"Potential_Waste_D-Hall"(t - dt) + (Unrecoverable_Food_Wasted_D + Student_Wasting_Food_D + Spoiling_Ingredients_D + Leftovers_going_bad_D - Trashing_Waste_D - Composting_Waste_D) * dt
INIT "Potential_Waste_D-Hall" = 0
Lbs
Wasted food that is no longer fit for human consumption. D-Hall
"Potential_waste_E-Hall"(t)
"Potential_waste_E-Hall"(t - dt) + (Unrecoverable_Food_Wasted + Student_Wasting_Food + Spoiling_Ingredients + Leftovers_going_bad - Trashing_Waste - Composting_Waste) * dt
INIT "Potential_waste_E-Hall" = 0
Lbs
Wasted food that is no longer fit for human consumption. E-Hall
"Prepared_Food_D-Hall"(t)
"Prepared_Food_D-Hall"(t - dt) + (Cooking_D + Reusing_food_D - Consuming_food_D - Creating_Leftover_food_D - Unrecoverable_Food_Wasted_D) * dt
INIT "Prepared_Food_D-Hall" = 0
Lbs
Prepared Food Made at D-Hall.
"Prepared_Food_E-Hall"(t)
"Prepared_Food_E-Hall"(t - dt) + (Cooking + Reusing_food - Consuming_food_E - Creating_Leftover_food - Unrecoverable_Food_Wasted) * dt
INIT "Prepared_Food_E-Hall" = 0
Lbs
Prepared Food made at E-Hall
Returned_Insecure_Students(t)
Returned_Insecure_Students(t - dt) + (Students_Fed_From_Pantry + Insecure_Students_Returning_from_Off_Campus + Insecure_Students_Returning_from_Dining_Hall - Students_Leaving_Food_Insecurity - Students_Still_Insecure) * dt
INIT Returned_Insecure_Students = 0
People
The food insecure students as they return from dining.
Secure_Students_Eating_in_Dining_Hall(t)
Secure_Students_Eating_in_Dining_Hall(t - dt) + (Secure_going_to_dining_hall - Secure_returning_from_Dining_Halls) * dt
INIT Secure_Students_Eating_in_Dining_Hall = 0
TRANSIT TIME = 1
CONTINUOUS
ACCEPT MULTIPLE BATCHES
People
Food secure students meeting needs through the dining halls.
CONVEYOR
Secure_Students_Eating_off_campus(t)
Secure_Students_Eating_off_campus(t - dt) + (Secure_going_off_campus - Secure_Returning_from_off_campus) * dt
INIT Secure_Students_Eating_off_campus = 0
TRANSIT TIME = 1
CONTINUOUS
ACCEPT MULTIPLE BATCHES
People
Food secure students meeting needs off campus.
CONVEYOR
Student_Population(t)
Student_Population(t - dt) + ( - Food_Insecurity_Initialization - Food_Security_Initialization) * dt
INIT Student_Population = Initial_Student_Population
People
The initial student population at JMU.
NON-NEGATIVE
Students_consistently_meeting_needs(t)
Students_consistently_meeting_needs(t - dt) + (Food_Security_Initialization + Students_Leaving_Food_Insecurity + Secure_returning_from_Dining_Halls + Secure_Returning_from_off_campus - Students_becoming_Food_insecure - Secure_going_off_campus - Secure_going_to_dining_hall) * dt
INIT Students_consistently_meeting_needs = 0
People
Students not recognized as food insecure.
Trash(t)
Trash(t - dt) + (Trashing_Waste_D + Trashing_Waste) * dt
INIT Trash = 0
Lbs
The quantity of food trashed over the course of a year.
Buying_Ingredients
PULSE(Aramark_Perceived_Demand*Ingredient_Buffer, Days_Supplying_for, Days_Supplying_for)
Lbs/Day
The Ingredients Bought be E-Hall
UNIFLOW
Buying_Ingredients_D
PULSE(Aramark_Perceived_Demand_D*Ingredient_Buffer, Days_Supplying_for_D, Days_Supplying_for_D)
Lbs/Day
The ingredients bought by D-Hall.
UNIFLOW
Composting_Waste
"Ratio_of_Compost/Trash"*"Potential_waste_E-Hall"
Lbs/Day
Waste being composted.
UNIFLOW
Composting_Waste_D
"Ratio_of_Compost/Trash"*"Potential_Waste_D-Hall"
Lbs/Day
Waste from D-Hall that is sent to compost.
UNIFLOW
Consuming_food_D
("Students_going_to_D-Hall")*Food_consumed_per_student_per_day*Effect_on_Prepared_Food_on_Student_Consumption_D
Lbs/Day
Food being consumed at D-Hall
UNIFLOW
Consuming_food_E
("Students_going_to_E-Hall")*Food_consumed_per_student_per_day*Effect_on_Prepared_Food_on_Student_Consumption
Lbs/Day
Flow of food being consumed at E-Hall
UNIFLOW
Cooking
(Aramark_Perceived_Demand/Days_Supplying_for)*Cooked_Food_Buffer
Lbs/Day
Flow of food being cooked at E-Hall
UNIFLOW
Cooking_D
(Aramark_Perceived_Demand_D/Days_Supplying_for_D)*Cooked_Food_Buffer
Lbs/Day
Flow of food being cooked at D-Hall
UNIFLOW
Creating_Leftover_food
IF "Prepared_Food_E-Hall"*Per_day -(Consuming_food_E+Unrecoverable_Food_Wasted)<=0 THEN 0 ELSE "Prepared_Food_E-Hall"*Per_day -(Consuming_food_E+Unrecoverable_Food_Wasted)
Lbs/Day
Food that is pulled from service and is still safe to consume.
UNIFLOW
Creating_Leftover_food_D
IF "Prepared_Food_D-Hall"*Per_day -(Consuming_food_D+Unrecoverable_Food_Wasted_D)<=0 THEN 0 ELSE "Prepared_Food_D-Hall"*Per_day -(Consuming_food_D+Unrecoverable_Food_Wasted_D)
Lbs/Day
Food that is pulled from service and is still safe to consume.
UNIFLOW
Food_Insecurity_Initialization
Student_Population*Initial_Proportion_Food_Insecure
OUTFLOW PRIORITY: 1
People/Days
Dumps fraction of initial students who are food insecure.
UNIFLOW
Food_Security_Initialization
Student_Population* (1-Initial_Proportion_Food_Insecure)
OUTFLOW PRIORITY: 2
People/Days
Dumps fraction of initial students that are food secure
UNIFLOW
Incoming_Pantry_donations_from_Blue_Ridge_Food_Bank
PULSE(1000, Days_Between_Each_donation_shipment, Days_Between_Each_donation_shipment)
Lbs/Day
The food that is specifically bought from Blue Ridge Food Bank for the JMU pantry
UNIFLOW
Insecure_Students_Returning_from_Dining_Hall
CONVEYOR OUTFLOW
People/Days
Food insecure students returning from a meal at the Dining Hall
Insecure_Students_Returning_from_Off_Campus
CONVEYOR OUTFLOW
People/Days
Food Insecure Students returning from a meal off campus
Insecure_Students_to_Dining_Hall
(Perceived_Food_Insecure_Students*Daily_Dining_Hall_Demand_Insecure)+Students_fed_with_punch_bundles
People/Days
Food Insecure students going to eat at a Dining Hall
UNIFLOW
Leftovers_going_bad
"Leftover_Food_E-Hall"*Leftover_Spoilage_Rate
Lbs/Day
Leftovers converted to waste.
UNIFLOW
Leftovers_going_bad_D
"Leftover_Food_D-Hall"*Leftover_Spoilage_Rate
Lbs/Day
Leftovers converted to waste.
UNIFLOW
Leftovers_to_Donation
PULSE( ("Leftover_Food_E-Hall"*Outside_Donation_Rate), Days_between_Donations, Days_between_Donations)
Lbs/Day
Flow of Leftover food to outside donation.
UNIFLOW
Leftovers_to_Donation_D
(PULSE( ("Leftover_Food_D-Hall"*Outside_Donation_Rate), Days_between_Donations, Days_between_Donations))*Dhall_Donation_Switch
Lbs/Day
Leftovers that are donated outside of the JMU system.
UNIFLOW
Leftovers_to_Pantry
"Leftover_Food_E-Hall"*Hall_to_Pantry_Donation_Rate*"E-Hall_to_Pantry_Donation_Switch"
Lbs/Day
Leftovers that are sent to the JMU Pantry
UNIFLOW
Leftovers_to_Pantry_D
"Leftover_Food_D-Hall"*Hall_to_Pantry_Donation_Rate* "D-Hall_to_Pantry_Donation_Switch"
Lbs/Day
Leftovers that are sent to the JMU Pantry.
UNIFLOW
Pantry_Spoiling
MAX(Pantry_Stock_of_Food//Days_to_Spoil, 0)
Lbs/day
Food spoiling from the JMU pantry
UNIFLOW
Presemester_order
PULSE(100000, 0, 220)
Lbs/Day
Pounds of food ordered right before a new semester starts.
UNIFLOW
Presemester_order_D
PULSE(100000, 0, 220)
Lbs/Day
The food D-Hall orders right before the new semester starts.
UNIFLOW
Reusing_food
"Leftover_Food_E-Hall"*Food_reutilization_rate
Lbs/Day
Flow of food being reused.
UNIFLOW
Reusing_food_D
"Leftover_Food_D-Hall"*Food_reutilization_rate
Lbs/Day
Leftovers that are reutilized at D-Hall
UNIFLOW
Secure_going_off_campus
Students_consistently_meeting_needs*Proportion_of_Secure_Students_eating_off_campus
People/Days
Food secure students moving to eat off campus.
UNIFLOW
Secure_going_to_dining_hall
Daily_Demand_Secure*Students_consistently_meeting_needs
People/Days
Food secure students moving to eat on campus.
UNIFLOW
Secure_returning_from_Dining_Halls
CONVEYOR OUTFLOW
People/Days
Food Secure students returning from a meal at the dining halls.
Secure_Returning_from_off_campus
CONVEYOR OUTFLOW
People/Days
Food Secure Students returning from a meal off campus.
Spoiling_Ingredients
"Ingredients_E-Hall"*Proportion_of_Ingredients_spoiling
Lbs/Day
Ingredients that spoil before they are used.
UNIFLOW
Spoiling_Ingredients_D
"Ingredients_D-Hall"*Proportion_of_Ingredients_spoiling
Lbs/Day
Ingredients that spoil before they are used.
UNIFLOW
Student_Wasting_Food
"Students_going_to_E-Hall"*Lbs_of_food_per_plate_trashed
Lbs/Day
Food that is wasted by students.
UNIFLOW
Student_Wasting_Food_D
"Students_going_to_D-Hall"*Lbs_of_food_per_plate_trashed
Lbs/Day
Food that is wasted by students.
UNIFLOW
Students_becoming_Food_insecure
Students_consistently_meeting_needs*Percentage_of_Students_becoming_food_insecure_per_day
People/Days
The natural flux of students between food security and food insecurity based on variable conditions outside of this model.
Students_Fed_From_Pantry
CONVEYOR OUTFLOW
People/Days
Food Insecure students returning from a meal at the JMU Pantry.
Students_Leaving_Food_Insecurity
Returned_Insecure_Students*(1-Proportion_Still_Insecure_Post_meal)+Students_Fed_From_Pantry*0.01
People/Days
Students that upon returning from a certain meal cross the invisible threshold into food security.
UNIFLOW
Students_pulling_from_pantry
MAX(Amount_students_pull_each_day*Insecure_Students_Eating_from_Pantry, 0)
Lbs/day
IF(Pantry_Stock_of_Food > Amount_students_pull_each_day*Insecure_Students_Eating_from_Pantry)
THEN (Insecure_Students_Eating_from_Pantry*Amount_students_pull_each_day )
ELSE 0
UNIFLOW
Students_Still_Insecure
Returned_Insecure_Students*Proportion_Still_Insecure_Post_meal
People/Days
Returned food insecure students that are still food insecure after the meal.
UNIFLOW
Students_to_Off_Campus
Perceived_Food_Insecure_Students*Proportion_of_Insecure_Students_eating_off_campus
People/Days
Food Insecure Students going to eat off campus
UNIFLOW
Students_to_Pantry
Perceived_Food_Insecure_Students*Proportion_of_Students_eating_from_pantry*Proportion_of_Students_willing_to_eat_from_pantry*Effect_of_Pantry_Stock_on_Students_Eating_from_Pantry
People/Days
Food Insecure students going to eat at the JMU Pantry
UNIFLOW
Trashing_Waste
(1-"Ratio_of_Compost/Trash")*"Potential_waste_E-Hall"
Lbs/Day
Waste being trashed.
UNIFLOW
Trashing_Waste_D
(1-"Ratio_of_Compost/Trash")*"Potential_Waste_D-Hall"
Lbs/Day
Waste that is sent to trash.
UNIFLOW
Unrecoverable_Food_Wasted
"Prepared_Food_E-Hall"*Proportion_of_food_wasted
Lbs/Day
Leftover food that is not safe for consumption
UNIFLOW
Unrecoverable_Food_Wasted_D
"Prepared_Food_D-Hall"*Proportion_of_food_wasted
Lbs/Day
Leftover food that is not safe for consumption
UNIFLOW
"2021_Revenue_gained_From_Dining"
32000000
Dollars
https://www.breezejmu.org/business/jmu-dining-hikes-meal-plan-prices-as-sales-fall-18-million/article_0c377ba8-9007-11eb-b707-9ff7e4a8a59f.html
Amount_students_pull_each_day
1
Lbs/People/Day
The pounds of food each student collects on average when visiting the pantry.
Aramark_Perceived_Demand
("Students_going_to_E-Hall")*Food_consumed_per_student_per_day*Days_Supplying_for
Lbs
The perceived demand for food at E-Hall
Aramark_Perceived_Demand_D
("Students_going_to_D-Hall")*Food_consumed_per_student_per_day*Days_Supplying_for_D
Lbs
The perceived demand for D-Hall food
Average_Meal_plan_cost_per_year
5000
Dollars/People
Average cost of the JMU meal plans per year, taken from the per semester cost on JMUs website
Cooked_Food_Buffer
1.2
Dimensionless
The buffer of extra food prepared ontop of the projected demand to ensure the halls don't run out of food.
Cost_of_Composting_Per_pound
45/2000
$/lbs
JMU contracts it's composting through Black Bear Composting, which charges 45$ per ton of food waste collected.
Cost_to_Compost_Waste
Compost*Cost_of_Composting_Per_pound
$
Total $ amount JMU pays to have their waste composted
Current_Cost_vs_Initial
(Average_Meal_plan_cost_per_year-Initial_Cost_of_Meal_Plan_per_year)/Initial_Cost_of_Meal_Plan_per_year
Dimensionless
The current cost of a meal plan per year compared to the original.
"D-Hall_/_E-Hall_split"
0.65
Dimensionless
The Split in Demand between D and E hall
"D-Hall_to_Pantry_Donation_Switch"
0
Dimensionless
Switch for enabling donation from D-Hall to the JMU Pantry
Daily_Demand_Secure
(Demand_Curve_over_year/2)*Proportion_of_students_with_meal_plan
Dimensionless/Days
The proportion of food secure students going to the dining hall each day.
Daily_Dining_Hall_Demand_Insecure
(Demand_Curve_over_year/2)*Proportion_of_students_with_meal_plan
Dimensionless/Days
Days_between_Donations
7
Days
Once every week leftover food is collected from e-hall and sent to Salvation Army.
Days_Between_Each_donation_shipment
7
Days
How often the pantry is buying from Blue Ridge Food Bank.
Days_Supplying_for
7
Days
The days that each order of ingredients is supplying for.
Days_Supplying_for_D
7
Days
The days that each order of ingredients is supplying for.
Days_to_Spoil
21
Days
Days taken for food to spoil in the pantry on average.
Default_proportion_of_students_eating_from_pantry
0.04
Dimensionless/Day
The proportion of students eating from the pantry by default.
Default_Proportion_of_Students_willing_to_eat_from_pantry
0.5
Dimensionless
The Default proportion of students that are willing to accept aid from the JMU pantry.
Demand_Curve_over_year
GRAPH(TIME) Points: (0.0, 0.000), (1.0, 0.000), (2.0, 0.000), (3.0, 0.000), (4.0, 0.000), (5.0, 0.000), (6.0, 0.000), (7.0, 0.000), (8.0, 0.000), (9.0, 0.000), (10.0, 0.000), (11.0, 0.000), (12.0, 0.000), (13.0, 0.000), (14.0, 0.000), (15.0, 0.000), (16.0, 0.000), (17.0, 0.100), (18.0, 2.000), (19.0, 2.000), (20.0, 2.000), (21.0, 1.900), (22.0, 1.900), (23.0, 1.900), (24.0, 1.900), (25.0, 1.800), (26.0, 1.800), (27.0, 1.800), (28.0, 1.700), (29.0, 1.700), (30.0, 1.000), (31.0, 1.600), (32.0, 1.600), (33.0, 1.500), (34.0, 1.400), (35.0, 1.300), (36.0, 1.200), (37.0, 1.100), (38.0, 1.000), (39.0, 1.000), (40.0, 0.900), (41.0, 1.000), (42.0, 1.000), (43.0, 1.000), (44.0, 1.000), (45.0, 1.000), (46.0, 1.000), (47.0, 1.000), (48.0, 1.000), (49.0, 1.000), (50.0, 0.900), (51.0, 1.000), (52.0, 1.000), (53.0, 1.000), (54.0, 1.000), (55.0, 1.000), (56.0, 1.000), (57.0, 2.000), (58.0, 0.800), (59.0, 1.000), (60.0, 1.000), (61.0, 1.000), (62.0, 1.000), (63.0, 1.000), (64.0, 1.000), (65.0, 1.000), (66.0, 1.200), (67.0, 1.000), (68.0, 1.000), (69.0, 1.000), (70.0, 1.000), (71.0, 1.000), (72.0, 1.000), (73.0, 1.000), (74.0, 0.900), (75.0, 0.500), (76.0, 0.200), (77.0, 0.200), (78.0, 0.200), (79.0, 0.200), (80.0, 0.200), (81.0, 0.500), (82.0, 0.900), (83.0, 1.000), (84.0, 1.000), (85.0, 1.000), (86.0, 1.000), (87.0, 1.000), (88.0, 1.000), (89.0, 1.000), (90.0, 1.000), (91.0, 1.200), (92.0, 1.000), (93.0, 1.000), (94.0, 2.000), (95.0, 1.000), (96.0, 1.000), (97.0, 1.000), (98.0, 1.000), (99.0, 0.800), (100.0, 1.000), (101.0, 1.000), (102.0, 2.000), (103.0, 1.000), (104.0, 1.000), (105.0, 1.000), (106.0, 1.000), (107.0, 0.600), (108.0, 1.000), (109.0, 1.000), (110.0, 1.000), (111.0, 0.800), (112.0, 1.000), (113.0, 1.000), (114.0, 1.000), (115.0, 1.000), (116.0, 0.900), (117.0, 1.000), (118.0, 1.000), (119.0, 2.000), (120.0, 1.000), (121.0, 1.000), (122.0, 1.000), (123.0, 1.000), (124.0, 1.000), (125.0, 0.600), (126.0, 1.000), (127.0, 1.000), (128.0, 0.900), (129.0, 0.900), (130.0, 0.800), (131.0, 0.700), (132.0, 0.500), (133.0, 0.200), (134.0, 0.200), (135.0, 0.200), (136.0, 0.200), (137.0, 0.200), (138.0, 0.200), (139.0, 0.200), (140.0, 0.200), (141.0, 0.200), (142.0, 0.200), (143.0, 0.200), (144.0, 0.200), (145.0, 0.200), (146.0, 0.200), (147.0, 0.200), (148.0, 0.200), (149.0, 0.200), (150.0, 0.200), (151.0, 0.200), (152.0, 0.200), (153.0, 0.200), (154.0, 0.200), (155.0, 0.200), (156.0, 0.200), (157.0, 0.200), (158.0, 0.200), (159.0, 0.200), (160.0, 0.200), (161.0, 0.200), (162.0, 0.200), (163.0, 0.200), (164.0, 0.200), (165.0, 0.200), (166.0, 0.200), (167.0, 0.200), (168.0, 0.200), (169.0, 0.200), (170.0, 0.200), (171.0, 0.200), (172.0, 0.200), (173.0, 0.200), (174.0, 0.200), (175.0, 0.200), (176.0, 0.200), (177.0, 0.200), (178.0, 0.200), (179.0, 0.200), (180.0, 0.200), (181.0, 0.200), (182.0, 0.200), (183.0, 0.200), (184.0, 0.200), (185.0, 0.200), (186.0, 0.200), (187.0, 0.200), (188.0, 0.200), (189.0, 0.200), (190.0, 0.200), (191.0, 0.200), (192.0, 0.200), (193.0, 0.200), (194.0, 0.200), (195.0, 0.200), (196.0, 0.200), (197.0, 0.200), (198.0, 0.200), (199.0, 0.200), (200.0, 0.200), (201.0, 0.200), (202.0, 0.200), (203.0, 0.200), (204.0, 0.200), (205.0, 0.200), (206.0, 0.200), (207.0, 0.200), (208.0, 0.200), (209.0, 0.200), (210.0, 0.200), (211.0, 0.200), (212.0, 0.200), (213.0, 0.200), (214.0, 0.200), (215.0, 0.200), (216.0, 0.200), (217.0, 0.200), (218.0, 0.200), (219.0, 0.200), (220.0, 0.200), (221.0, 0.200), (222.0, 0.200), (223.0, 0.200), (224.0, 0.200), (225.0, 0.200), (226.0, 0.200), (227.0, 0.600), (228.0, 0.700), (229.0, 0.800), (230.0, 0.900), (231.0, 0.900), (232.0, 1.000), (233.0, 1.400), (234.0, 1.500), (235.0, 1.600), (236.0, 2.000), (237.0, 2.000), (238.0, 2.000), (239.0, 1.900), (240.0, 1.900), (241.0, 1.900), (242.0, 1.800), (243.0, 1.800), (244.0, 1.700), (245.0, 1.700), (246.0, 1.600), (247.0, 1.600), (248.0, 1.500), (249.0, 1.500), (250.0, 1.400), (251.0, 1.400), (252.0, 1.300), (253.0, 1.300), (254.0, 1.200), (255.0, 1.200), (256.0, 1.100), (257.0, 1.100), (258.0, 2.000), (259.0, 1.000), (260.0, 1.000), (261.0, 1.000), (262.0, 1.000), (263.0, 1.000), (264.0, 1.000), (265.0, 1.000), (266.0, 2.000), (267.0, 1.000), (268.0, 1.000), (269.0, 1.000), (270.0, 1.000), (271.0, 1.000), (272.0, 1.000), (273.0, 1.000), (274.0, 1.000), (275.0, 1.000), (276.0, 1.000), (277.0, 1.000), (278.0, 1.000), (279.0, 1.000), (280.0, 1.000), (281.0, 1.000), (282.0, 1.000), (283.0, 1.000), (284.0, 1.000), (285.0, 1.000), (286.0, 1.000), (287.0, 1.000), (288.0, 1.000), (289.0, 1.000), (290.0, 1.000), (291.0, 1.000), (292.0, 1.000), (293.0, 1.000), (294.0, 1.000), (295.0, 1.000), (296.0, 1.000), (297.0, 1.000), (298.0, 2.000), (299.0, 1.000), (300.0, 1.000), (301.0, 1.000), (302.0, 1.000), (303.0, 1.000), (304.0, 1.000), (305.0, 1.000), (306.0, 1.000), (307.0, 1.000), (308.0, 1.000), (309.0, 1.000), (310.0, 1.000), (311.0, 1.000), (312.0, 1.000), (313.0, 1.000), (314.0, 1.000), (315.0, 1.000), (316.0, 1.000), (317.0, 1.000), (318.0, 1.000), (319.0, 1.000), (320.0, 0.400), (321.0, 1.000), (322.0, 2.000), (323.0, 1.000), (324.0, 1.000), (325.0, 1.000), (326.0, 1.000), (327.0, 0.000), (328.0, 0.000), (329.0, 0.000), (330.0, 0.000), (331.0, 0.000), (332.0, 0.000), (333.0, 0.000), (334.0, 0.000), (335.0, 0.000), (336.0, 1.000), (337.0, 1.000), (338.0, 1.000), (339.0, 2.000), (340.0, 1.000), (341.0, 1.000), (342.0, 1.500), (343.0, 0.900), (344.0, 0.900), (345.0, 0.700), (346.0, 0.600), (347.0, 0.500), (348.0, 0.300), (349.0, 0.000), (350.0, 0.000), (351.0, 0.000), (352.0, 0.000), (353.0, 0.000), (354.0, 0.000), (355.0, 0.000), (356.0, 0.000), (357.0, 0.000), (358.0, 0.000), (359.0, 0.000), (360.0, 0.000), (361.0, 0.000), (362.0, 0.000), (363.0, 0.000), (364.0, 0.000), (365.0, 0.000)
Dimensionless/Days
A 0 - 2 multiplier on demand based on the break schedule. Another layer is added on to this curve to give variance in demand over random days to account for sports events, specialty dinners in the dining halls, and weather changing demand.
Demand_Error
ABS(("Prepared_Food_E-Hall"*Per_day-Consuming_food_E)//"Prepared_Food_E-Hall")
Dimensionless/Days
Error between the amount of food supplied vs. demanded.
Dhall_Donation_Switch
0
Dimensionless
Switch for donating food from D-Hall to outside the JMU system
"E-Hall_to_Pantry_Donation_Switch"
0
Dimensionless
Switch to toggle sending leftover food from E-Hall to the JMU Pantry.
Effect_of_cost_on_proportion_of_students_with_meal_plan
GRAPH(Current_Cost_vs_Initial) Points: (-1.000, 1.2464), (-0.800, 1.1754), (-0.600, 1.1576), (-0.400, 1.1043), (-0.200, 1.0723), (0.000, 1.0012), (0.200, 0.9443), (0.400, 0.8412), (0.600, 0.7701), (0.800, 0.5675), (1.000, 0.5000)
Dimensionless
The effect of the cost of a meal plan on the number of students that buy one.
Effect_of_Pantry_Stock_on_Students_Eating_from_Pantry
GRAPH(Pantry_Stock_of_Food/Expected_Stock_of_Food) Points: (0.000, 0.000), (0.200, 0.01895), (0.400, 0.06512), (0.600, 0.1748), (0.800, 0.4014), (1.000, 0.750), (1.200, 1.099), (1.400, 1.325), (1.600, 1.435), (1.800, 1.481), (2.000, 1.500)
Dimensionless
Effect of the stock of food on how many students eat from the pantry. High food stocks attract more students to eat from the pantry.
Effect_of_Students_with_meal_plan_on_food_insecurity
((Initial_Proportion_with_meal_plan-Proportion_of_students_with_meal_plan)/Initial_Proportion_with_meal_plan)*10
Dimensionless/Days
The effect of the proportion of students with a meal plan on the average student food insecurity.
Effect_on_Prepared_Food_on_Student_Consumption
GRAPH(Ratio_of_available_food_to_Ideal) Points: (0.000, 0.000), (0.200, 0.001955), (0.400, 0.01035), (0.600, 0.04632), (0.800, 0.1808), (1.000, 0.500), (1.200, 0.8192), (1.400, 0.9537), (1.600, 0.9896), (1.800, 0.998), (2.000, 1.000)
Dimensionless
The effect of the amount of prepared food available on the amount of food consumed by students.
Effect_on_Prepared_Food_on_Student_Consumption_D
GRAPH(Ratio_of_available_food_to_Ideal_D) Points: (0.000, 0.000), (0.200, 0.001955), (0.400, 0.01035), (0.600, 0.04632), (0.800, 0.1808), (1.000, 0.500), (1.200, 0.8192), (1.400, 0.9537), (1.600, 0.9896), (1.800, 0.998), (2.000, 1.000)
Dimensionless
The effect of the amount of prepared food available on the amount of food consumed by students.
Expected_Stock_of_Food
700
Lbs
The expected Lbs. of food that should be in the pantry for optimal functioning. Above the limit does not impede operations.
Food_consumed_per_student_per_day
2
Lbs/(People*Days)
Average Lbs. of food that each student consumes when going to the dining halls.
Food_reutilization_rate
0.3*(1+Food_Reutilization_Rate_Switch*0.5)
Dimensionless/Day
Proportion of leftover food that can be reutilized for another meal.
Food_Reutilization_Rate_Switch
0
Dimensionless/Days
Switch to begin increased reutilization of leftover food.
Hall_to_Pantry_Donation_Rate
0.5
Dimensionless/Days
Proportion of left
"Ideal_quantity_of_food_D-Hall"
Food_consumed_per_student_per_day*("Students_going_to_D-Hall")/Per_day
Lbs
The ideal quantity of food at D-Hall to meet demand.
"Ideal_quantity_of_food_E-Hall"
Food_consumed_per_student_per_day*("Students_going_to_E-Hall")/Per_day
Lbs
The ideal quantity of food at E-Hall to meet demand
Ingredient_Buffer
1.2
Dimensionless
A buffer of ingredients to ensure the kitchen does not run out.
Initial_Cost_of_Meal_Plan_per_year
5000
Dollars/People
Initial Cost of a meal plan per year per student, extrapolated from the prices of each meal plan
Initial_Proportion_Food_Insecure
0.385
Dimensionless/Day
The initial percentage of students that are food insecure while on campus. Obtained from a JMU pantry survey.
Initial_Proportion_with_meal_plan
0.38
Dimensionless
All Freshman are required to have a meal plan. ~30% of student body therefore must have a meal plan.
2021 revenue for dining was 32 million. Generously assuming that the full revenue comes from meal plans, and the cost of meal plans averages around 2000 per semester, only ~8000 students bought a meal plan that year.
With 21000 students at JMU that year, that gives a proportion of 0.38.
https://www.breezejmu.org/business/jmu-dining-hikes-meal-plan-prices-as-sales-fall-18-million/article_0c377ba8-9007-11eb-b707-9ff7e4a8a59f.html
Initial_Student_Population
22758
People
The initial JMU student population.
KNOWN_Existing_Food_Insecurity
38.9
Dimensionless
# from 2019 JMU pantry report.
KNOWN_Yearly_Compost_Value
GRAPH(TIME) Points: (0.0, 320000), (1.43137254902, 320000), (2.86274509804, 320000), (4.29411764706, 320000), (5.72549019608, 320000), (7.1568627451, 320000), (8.58823529412, 320000), (10.0196078431, 320000), (11.4509803922, 320000), (12.8823529412, 320000), (14.3137254902, 320000), (15.7450980392, 320000), (17.1764705882, 320000), (18.6078431373, 320000), (20.0392156863, 320000), (21.4705882353, 320000), (22.9019607843, 320000), (24.3333333333, 320000), (25.7647058824, 320000), (27.1960784314, 320000), (28.6274509804, 320000), (30.0588235294, 320000), (31.4901960784, 320000), (32.9215686275, 320000), (34.3529411765, 320000), (35.7843137255, 320000), (37.2156862745, 320000), (38.6470588235, 320000), (40.0784313725, 320000), (41.5098039216, 320000), (42.9411764706, 320000), (44.3725490196, 320000), (45.8039215686, 320000), (47.2352941176, 320000), (48.6666666667, 320000), (50.0980392157, 320000), (51.5294117647, 320000), (52.9607843137, 320000), (54.3921568627, 320000), (55.8235294118, 320000), (57.2549019608, 320000), (58.6862745098, 320000), (60.1176470588, 320000), (61.5490196078, 320000), (62.9803921569, 320000), (64.4117647059, 320000), (65.8431372549, 320000), (67.2745098039, 320000), (68.7058823529, 320000), (70.137254902, 320000), (71.568627451, 320000), (73.0, 320000), (74.431372549, 320000), (75.862745098, 320000), (77.2941176471, 320000), (78.7254901961, 320000), (80.1568627451, 320000), (81.5882352941, 320000), (83.0196078431, 320000), (84.4509803922, 320000), (85.8823529412, 320000), (87.3137254902, 320000), (88.7450980392, 320000), (90.1764705882, 320000), (91.6078431373, 320000), (93.0392156863, 320000), (94.4705882353, 320000), (95.9019607843, 320000), (97.3333333333, 320000), (98.7647058824, 320000), (100.196078431, 320000), (101.62745098, 320000), (103.058823529, 320000), (104.490196078, 320000), (105.921568627, 320000), (107.352941176, 320000), (108.784313725, 320000), (110.215686275, 320000), (111.647058824, 320000), (113.078431373, 320000), (114.509803922, 320000), (115.941176471, 320000), (117.37254902, 320000), (118.803921569, 320000), (120.235294118, 320000), (121.666666667, 320000), (123.098039216, 320000), (124.529411765, 320000), (125.960784314, 320000), (127.392156863, 320000), (128.823529412, 320000), (130.254901961, 320000), (131.68627451, 320000), (133.117647059, 320000), (134.549019608, 320000), (135.980392157, 320000), (137.411764706, 320000), (138.843137255, 320000), (140.274509804, 320000), (141.705882353, 320000), (143.137254902, 320000), (144.568627451, 320000), (146.0, 320000), (147.431372549, 320000), (148.862745098, 320000), (150.294117647, 320000), (151.725490196, 320000), (153.156862745, 320000), (154.588235294, 320000), (156.019607843, 320000), (157.450980392, 320000), (158.882352941, 320000), (160.31372549, 320000), (161.745098039, 320000), (163.176470588, 320000), (164.607843137, 320000), (166.039215686, 320000), (167.470588235, 320000), (168.901960784, 320000), (170.333333333, 320000), (171.764705882, 320000), (173.196078431, 320000), (174.62745098, 320000), (176.058823529, 320000), (177.490196078, 320000), (178.921568627, 320000), (180.352941176, 320000), (181.784313725, 320000), (183.215686275, 320000), (184.647058824, 320000), (186.078431373, 320000), (187.509803922, 320000), (188.941176471, 320000), (190.37254902, 320000), (191.803921569, 320000), (193.235294118, 320000), (194.666666667, 320000), (196.098039216, 320000), (197.529411765, 320000), (198.960784314, 320000), (200.392156863, 320000), (201.823529412, 320000), (203.254901961, 320000), (204.68627451, 320000), (206.117647059, 320000), (207.549019608, 320000), (208.980392157, 320000), (210.411764706, 320000), (211.843137255, 320000), (213.274509804, 320000), (214.705882353, 320000), (216.137254902, 320000), (217.568627451, 320000), (219.0, 320000), (220.431372549, 320000), (221.862745098, 320000), (223.294117647, 320000), (224.725490196, 320000), (226.156862745, 320000), (227.588235294, 320000), (229.019607843, 320000), (230.450980392, 320000), (231.882352941, 320000), (233.31372549, 320000), (234.745098039, 320000), (236.176470588, 320000), (237.607843137, 320000), (239.039215686, 320000), (240.470588235, 320000), (241.901960784, 320000), (243.333333333, 320000), (244.764705882, 320000), (246.196078431, 320000), (247.62745098, 320000), (249.058823529, 320000), (250.490196078, 320000), (251.921568627, 320000), (253.352941176, 320000), (254.784313725, 320000), (256.215686275, 320000), (257.647058824, 320000), (259.078431373, 320000), (260.509803922, 320000), (261.941176471, 320000), (263.37254902, 320000), (264.803921569, 320000), (266.235294118, 320000), (267.666666667, 320000), (269.098039216, 320000), (270.529411765, 320000), (271.960784314, 320000), (273.392156863, 320000), (274.823529412, 320000), (276.254901961, 320000), (277.68627451, 320000), (279.117647059, 320000), (280.549019608, 320000), (281.980392157, 320000), (283.411764706, 320000), (284.843137255, 320000), (286.274509804, 320000), (287.705882353, 320000), (289.137254902, 320000), (290.568627451, 320000), (292.0, 320000), (293.431372549, 320000), (294.862745098, 320000), (296.294117647, 320000), (297.725490196, 320000), (299.156862745, 320000), (300.588235294, 320000), (302.019607843, 320000), (303.450980392, 320000), (304.882352941, 320000), (306.31372549, 320000), (307.745098039, 320000), (309.176470588, 320000), (310.607843137, 320000), (312.039215686, 320000), (313.470588235, 320000), (314.901960784, 320000), (316.333333333, 320000), (317.764705882, 320000), (319.196078431, 320000), (320.62745098, 320000), (322.058823529, 320000), (323.490196078, 320000), (324.921568627, 320000), (326.352941176, 320000), (327.784313725, 320000), (329.215686275, 320000), (330.647058824, 320000), (332.078431373, 320000), (333.509803922, 320000), (334.941176471, 320000), (336.37254902, 320000), (337.803921569, 320000), (339.235294118, 320000), (340.666666667, 320000), (342.098039216, 320000), (343.529411765, 320000), (344.960784314, 320000), (346.392156863, 320000), (347.823529412, 320000), (349.254901961, 320000), (350.68627451, 320000), (352.117647059, 320000), (353.549019608, 320000), (354.980392157, 320000), (356.411764706, 320000), (357.843137255, 320000), (359.274509804, 320000), (360.705882353, 320000), (362.137254902, 320000), (363.568627451, 320000), (365.0, 320000)
Lbs
159.96 tons of food waste composted,
# from Aramark
Lbs_of_food_per_plate_trashed
0.22
Lbs/(People*Days)
From Aramark wipe out waste event, each student produces ~0.22 pounds of food waste
Leftover_Spoilage_Rate
0.1
Dimensionless/Days
Proportion of Leftover food that goes bad before reused, or donated.
Lump_Insecure_Students
Insecure_Students_Eating_from_Pantry + Insecure_Students_Eating_in_Dining_Hall + Insecure_Students_Eating_off_campus + Perceived_Food_Insecure_Students + Returned_Insecure_Students
People
The lump sum of all food insecure students throughout the model
SUMMING CONVERTER
Lump_Secure_Students
Secure_Students_Eating_in_Dining_Hall + Secure_Students_Eating_off_campus + Students_consistently_meeting_needs
People
The lump sum of all food secure students throughout the model
SUMMING CONVERTER
Max_Punch_Donations_per_student_per_day
2
Punches/People
The maximum number of punches each student can donate per day.
Net_Flow_Prepared_Food
Prepared_Food_Inflows-Prepared_Food_Outflows
Lbs/day
The Net Flow of prepared food per day.
Number_of_Punches_Donated
Initial_Student_Population*Proportion_of_students_with_meal_plan*Max_Punch_Donations_per_student_per_day*Punch_Donation_Program_Utilization_Rate
Punches
The total number of punches donated.
Outside_Donation_Rate
0.002
Dimensionless
Proportion of leftover food that is donated outside the JMU system
Pantry_Awareness_Campaign
1
Dimensionless
Switch for an awareness campaign for the JMU Pantry
Pantry_Destigmatization_Campaign
1
Dimensionless
Switch for a campaign to destigmatize the pantry.
Per_day
1
Dimensionless/Days
1 day.
Percentage_of_Students_becoming_food_insecure_per_day
0.0001*Effect_of_Students_with_meal_plan_on_food_insecurity
Dimensionless/Days
The percentage of students that become food insecure each day because of outside factors.
Prepared_Food_Inflows
Cooking + Cooking_D + Reusing_food + Reusing_food_D
Lbs/day
Sum of all inflows for prepared food
SUMMING CONVERTER
Prepared_Food_Outflows
Consuming_food_D + Consuming_food_E + Creating_Leftover_food + Creating_Leftover_food_D + Unrecoverable_Food_Wasted + Unrecoverable_Food_Wasted_D
Lbs/day
Sum of all outflows for prepared food
SUMMING CONVERTER
Proportion_Food_Insecure
(Lump_Insecure_Students*(Proportion_of_Food_Insecure_Students_that_are_still_food_secure_over_breaks) // (Lump_Insecure_Students+Lump_Secure_Students))*100
Dimensionless
The proportion of students that are food insecure at any given time.
Proportion_of_Aware_Students_Willing_to_Use_Program
0.5
Dimensionless
The fraction of students that know about the program and are willing to use it. Speculated
Proportion_of_Food_Insecure_Students_that_are_still_food_secure_over_breaks
IF Demand_Curve_over_year < 0.4 THEN 0.6 ELSE 1
Dimensionless
The proportion of students that are food insecure at home as well as on campus.
Proportion_of_food_wasted
0.05
Dimensionless/Day
The proportion of prepared food that is wasted.
Proportion_of_Ingredients_spoiling
0.005
Dimensionless/Day
Proportion of Ingredients that spoil before being used because of kitchen inefficiencies
Proportion_of_Insecure_Students_eating_off_campus
(1-Daily_Dining_Hall_Demand_Insecure-Proportion_of_Students_eating_from_pantry)*0.1
Dimensionless/Day
The proportion of food insecure students that meet their needs off campus
Proportion_of_Secure_Students_eating_off_campus
1-Daily_Demand_Secure
Dimensionless/Days
The proportion of food secure students that are eating off campus
Proportion_of_Students_Aware_of_Program
0.01
Dimensionless
The fraction of students that are aware of the program. Speculated.
Proportion_of_Students_eating_from_pantry
Default_proportion_of_students_eating_from_pantry*Pantry_Awareness_Campaign
Dimensionless/Day
How many students on average eat from the pantry
Proportion_of_Students_willing_to_eat_from_pantry
Default_Proportion_of_Students_willing_to_eat_from_pantry*Pantry_Destigmatization_Campaign
Dimensionless
The proportion of students that are willing to eat from the JMU pantry
Proportion_of_students_with_meal_plan
Initial_Proportion_with_meal_plan*Effect_of_cost_on_proportion_of_students_with_meal_plan
Dimensionless
The proportion of students that buy a meal plan.
Proportion_Still_Insecure_Post_meal
0.9999
Dimensionless/Days
The proportion of food insecure students that are still food insecure after a meal.
Punch_Donation_Program_Utilization_Rate
Proportion_of_Students_Aware_of_Program*Proportion_of_Aware_Students_Willing_to_Use_Program
Dimensionless
Combined percentage of how the punch donation program is utilized.
Punch_Donation_Switch
1
Dimensionless
Switch to turn on/off the Punch donation program. On by default as the program is currently running.
Punches_per_bundle
10
Punches/People*Days
The number of punches in each punch bundle given to students.
Ratio_of_available_food_to_Ideal
"Prepared_Food_E-Hall"//"Ideal_quantity_of_food_E-Hall"
Dimensionless
How much food is available compared to how much is needed.
Ratio_of_available_food_to_Ideal_D
"Prepared_Food_D-Hall"//"Ideal_quantity_of_food_D-Hall"
Dimensionless
How much food is available compared to how much is needed.
"Ratio_of_Compost/Trash"
0.5
Dimensionless/Days
Ratio of Waste that is trashed vs. collected for composting.
Simulated_Revenue_from_Meal_Plans
Initial_Student_Population*Proportion_of_students_with_meal_plan*Average_Meal_plan_cost_per_year
Dollars
The Revenue JMU should make from meal plans.
Students_fed_with_punch_bundles
(Number_of_Punches_Donated/Punches_per_bundle)*Punch_Donation_Switch
People/Days
Number of students that are fed from the punch bundles .
"Students_going_to_D-Hall"
Students_in_Dining_Hall*"D-Hall_/_E-Hall_split"
People
# of students eating at D-Hall
"Students_going_to_E-Hall"
Students_in_Dining_Hall*(1-"D-Hall_/_E-Hall_split")
People
# of students eating at E-Hall
Students_in_Dining_Hall
Insecure_Students_Eating_in_Dining_Hall+Secure_Students_Eating_in_Dining_Hall
People
# of students eating at both dining halls
Total_Donation_per_week
Leftovers_to_Donation + Leftovers_to_Donation_D
Lbs/day
The total donations of food outside of the JMU system every week.
SUMMING CONVERTER