CN109408228B - A Crowdsensing Task Allocation Method Based on Budget Allocation - Google Patents

Abstract

A crowdsensing task assignment method based on budget allocation, collects a set of sensing tasks submitted by task requesters Γ={τ ₁ ,...,τ _i ,...,τ _n }, where n is a finite natural number, Task τ _i =(B _i ,Q _i ), _Bi is the total budget for completing the task τ _i , which is a finite positive real number, and Qi is the quality requirement value of the task τ _{i ,} which is a finite positive integer; Set U={u ₁ ,...,u _j ,..., _um } and the quality level q _j of user u _j in the user set, j∈{1,...,m}; calculate user u The cost c _ij of _j completing the task τ _i , and the benefit w _ij of the user u _j completing the task τ _i is determined; according to the quality requirement Q _i of the task τ _i and the quality level q _j of the user u _j , the tasks in the perception task set Γ are determined. Assignment, according to the task assignment result, calculate and pay the user reward r _j .

Description

A Crowdsensing Task Allocation Method Based on Budget Allocation

technical field

The invention belongs to the technical field of point digital data processing, and in particular relates to a method for assigning a group intelligence perception task based on budget allocation.

Background technique

In recent years, mobile smart devices (such as smart phones, tablet computers, smart watches, etc.) have been widely popularized with the rapid development of mobile computing and wireless communication technologies. Such as camera, microphone, gravimeter, GPS, gyroscope, temperature sensor, blood pressure sensor, etc.). On this basis, people use the mobile devices used by a large number of ordinary users as the basic perception unit to cooperate through the Internet of Things/mobile Internet to realize the distribution of perception tasks and the collection and utilization of perception data, and finally complete large-scale and complex urban and social perception tasks. . In order to make full and low-cost use of the sensing, computing and storage resources of these mobile smart devices, the crowd-sensing computing model emerges and has been widely studied and applied. Different from the sensing methods based on sensor networks and the Internet of Things, crowd sensing uses a large number of ordinary users as the sensing source, emphasizes the use of the widespread distribution, flexible mobility and opportunity connectivity of the public for sensing, and provides intelligence for urban and social management. Auxiliary support. It can be applied in many important fields, such as intelligent transportation, public safety, social recommendation, environmental monitoring, urban public management and many other fields, so it has received great attention from governments, industries and academia around the world.

A crowd-sensing application system generally includes three components: cloud platform (ie system), task requester and task completer. The task requester publishes the perception task (hereinafter referred to as the task) requirements to the cloud platform, and receives the task results from the cloud platform; the cloud platform is mainly responsible for task release, task allocation, perception data collection and task quality assessment; task completers, that is, carry mobile intelligence Ordinary mobile users of the device (hereinafter referred to as users) receive assigned tasks from the cloud platform and are responsible for data perception and collection, and send the perception data to the cloud platform. In the crowd-sensing system, task assignment is the basis for implementing crowd-sensing. The cloud platform needs to allocate (ie, assign) each task to many users participating in crowdsensing according to the task requirements submitted by the task requester and combined with the status of the current online users. The basis for the assignment is to achieve specific optimization goals, such as maximizing Task acceptance rate, maximizing overall revenue, etc.

Judging from the existing research results, the current task allocation methods and systems for crowd awareness have not considered the following aspects: 1. The platform allocates the task budget reasonably to improve the task acceptance rate and system benefits; 2. Select Users of the appropriate quality level and through the cooperation of users to meet the quality requirements of the task, to save the task budget. In the existing task allocation method, the platform generally collects all tasks that need to be performed currently, sends the task set to be performed to all users, and then allocates tasks according to the specific conditions of each user. Generally, it is assumed that the budget of a task is only used for assignment of this task. In fact, the quality level of users is limited, and multiple users can obtain higher-quality perceptual data by cooperating to complete a task. Therefore, multiple users with different quality levels can cooperate to complete a task requiring high quality. In addition, the platform can improve the rationality of task budget allocation. For example, the platform can make full use of the remaining budget of tasks and allocate it to some tasks with insufficient budgets, which is expected to greatly improve the task allocation rate while saving task budgets. However, the current online task assignment methods have not considered these factors, which largely limits the application scope of crowd sensing.

Therefore, in order to adapt to large-scale crowd-sensing application scenarios and improve the task allocation rate of the platform, considering the relationship between the quality requirements of tasks and the quality level of users and the reasonable allocation of task budgets by the platform, a A crowd-sensing task assignment method based on budget allocation is very necessary.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to overcome the shortcomings of the existing crowd-sensing sensing task assignment methods, and provide a crowd-sensing sensing task assignment method based on budget allocation with reasonable design, high task assignment rate and task budget saving.

The technical solution adopted to solve the above-mentioned technical problems is a method for allocating tasks for crowdsensing based on budget allocation, which is characterized in that it consists of the following steps:

(1) Collect the set of perception tasks submitted by the task requester Γ={τ ₁ ,...,τ _i ,...,τ _n }, i∈{1,...,n}, where n is a finite A natural number, task τ _i =(B _i ,Q _i ), _Bi is the total budget for completing the task τ _i , which is a finite positive real number, and Qi is the quality requirement value of the task τ _{i ,} which is a finite positive integer;

(2) Collect the user set U={u ₁ ,...,u _j ,..., _um } and the quality level q _j of the user u _j in the user set, j∈{1,...,m }, m is a finite natural number;

(3) Calculate the cost c _ij for the user u _j to complete the task τ _i , and determine the profit w _ij for the user u _j to complete the task τ _i ;

(4) Allocate the tasks in the sensing task set Γ according to the quality requirement Qi and budget B _i of the task τ _i and the quality level _{q j of} the user u _j . The specific allocation formula is as follows:

表示平台以往任务分配后的结余预算，为一个正实数，η∈(0,1)表示结余预算的利用率；In the formula, y _i indicates whether the task τ _i is successfully assigned, y _i =1 indicates that the task τ _i is successfully assigned, τ _i ∈Γ, y _i =0 indicates that the task τ _i assignment fails; x _ij indicates whether the task τ _i is assigned to the User u _j , u _j ∈ U, x _ij =1 indicates that task τ _i is assigned to user u _j , x _ij =0 indicates that task τ _i is not assigned to user u _j , δ indicates that all users participating in task τ _i The difference between the sum of the rewards and the total budget of the task,

Represents the balance budget after the platform's previous task allocation, which is a positive real number, and η∈(0,1) represents the utilization rate of the balance budget;

(5) Calculate and pay the user reward r _j according to the task assignment result;

As a preferred technical solution, in the step (3) the cost c _ij for the user u _j to complete the task τ _i ,

c _ij =f(Q _i ,q _j ) (2)

In the formula, q _j is the quality level of the user u _j , and the function f(Q _i , q _j ) is a non-negative function that increases monotonically with q _j ; the user u _j 's income w _ij for completing the task τ _i ,

w _ij =g(Q _i ,q _j ) (3)

The function g(Q _i , q _j ) is a non-negative function that increases monotonically with q _j ;

As a preferred technical solution, the formula (1) in the step (4) is an integer programming problem, and in order to efficiently solve the problem, it is allocated according to the following method:

表示平台以往任务分配后的结余预算，初始时Q′_i＝Q_i，B′_i＝B_i，

令集合

为剩余的用户集合，集合U'为可选用的用户集合，初始时集合

表示能执行任务τ_i的用户集合，初始

S1: Let the set Γ' be the set of tasks to be assigned, initially Γ'=Γ, for any task τ _i , τ _i ∈Γ', let Q' _i represent the remaining quality requirement value of the task τ _i , and B' _i represent the remaining budget of task τ _i ,

Represents the balance budget of the platform after the assignment of tasks in the past. Initially, Q′ _i =Q _i , B′ _i =B _i ,

set of orders

is the remaining user set, and the set U' is the optional user set. gather

represents the set of users who can perform the task τ _i , the initial

S2: Judgment set Whether it is established, if so, according to the following formula

否则，停止；Find a specific task τ _i* , the specific task τ _i* is the task with the lowest quality requirement within the unit budget, the initial quality requirement value of the specific task τ _i* is Q′ _i* =Q _i* , the specific task τ _i* Remaining budget B′ _i* =B _i* , the set of users that can be selected for a specific task τ _i*

Otherwise, stop;

S3: Find a user u _j* that is closest to the quality requirement of a specific task τ _i* according to the following formula,

In the formula, c _i*j represents the cost paid by user u _j to perform the assigned specific task τ _i* , w _i*j represents the pure benefit brought by user u _j when performing the assigned specific task τ _i* , If it can be found, then turn to step S4; otherwise, delete this task in the task set Γ, and make y _i* =0, that is, the assignment of the specific task τ _i* fails, and then turn to step S2;

S4: Determine whether the difference between the reward of the user u _j* performing the specific task τ _i* and the budget of the specific task τ _i* , that is, whether the following formula holds,

(c _i*j* +w _i*j* )-B′ _i* ≤δ (6)

In the formula, c _i*j* represents the total cost paid by user u _j * to perform the assigned specific task τ _i* , and w _i*j* represents the pure cost incurred by user u _j* when performing the assigned specific task τ _i* . If the income is established, turn to step S5; otherwise, delete user u _j* in the optional user set U', and then turn to step S3 to find a new user;

来帮助特定任务τ_i*完成分配，即下式是否成立，S5: Determine whether the platform can use the balance budget

to help a specific task τ _i* complete the assignment, that is, whether the following formula holds,

中，转向步骤S6；否则，应把用户u_j*从可选用的用户集合U'中删除，再转向步骤S3寻找新的用户；If so, add user u _j* to the set of users that meet the quality requirements of task τ _i*

In, turn to step S6; Otherwise, user u _j* should be deleted from the optional user set U', then turn to step S3 to find new users;

S6: delete the user u _j* from the selectable user set U', according to the formula Q' _i* =Q _i* '-q _j* and the formula B' _i* =B' _i* -(c _{i*j *} +w _i*j* ) update the values of Q′ _i* and B′ _i* , and then judge whether the quality requirements of the task τ _i* are satisfied, that is, whether the formula Q′ _i* ≤ 0 is established, if so, turn to step S7 ; If not established, turn to step S3 and continue to look for the user;

即为执行任务τ_i*的一个可行的用户集合，令y_i*＝1，即特定任务τ_i*成功分配，令x_i*j*＝1，即将任务τ_i分配给用户u_j*，计算结余预算令Γ'＝Γ'-{τ_i*}，

再转向步骤S2下一任务进行分配。S7: User Collection

is a feasible set of users to perform task τ _i* , let y _i* =1, that is, a specific task τ _i* is successfully assigned, let x _i*j* =1, that is, assign task τ _i to user u _j* , Calculate balance budget Let Γ'=Γ'-{τ _i* },

Then turn to step S2 to assign the next task.

As a preferred technical solution, the remuneration r _{j * obtained by the user u j*} performing the specific task τ _i* in the step (5),

When user u _j* completes a specific task τ _i* and gets paid, set all the values of x _i*j* to 0, τ _i* ∈ Γ, and add user u _j* to the user set U.

As a preferred technical solution, in the step (1), when a new perception task submitted by the task requester is collected, the new task is added to the set Γ; when an assigned task is completed, then remove it from the set Γ.

As a preferred technical solution, in the step (2), when it is detected that the user leaves the system, the user is deleted from the set U; when a new user is collected, the user is added to the set U.

The beneficial effects of the present invention are as follows:

1. The present invention considers the relationship between the quality requirements of the task and the user's quality level. Since multiple users cooperate to complete the task, higher quality perception data can be obtained. Therefore, under the constraint of the task budget, according to the quality requirement value of the task To select users of different quality levels to cooperate to complete the perception task, it is expected to greatly save the task budget while satisfying the quality of the perception data.

2. The present invention considers the impact of the task budget on task allocation, and proposes a method that can improve the task allocation rate. The task budget will be split into two parts by the platform, and a part of the budget is used to ensure the normal distribution of the task, The remaining part of the budget will be reasonably allocated by the platform to those tasks that cannot be allocated due to insufficient budget. During the allocation process, all tasks with insufficient budget are equally supplemented by the platform budget, which reflects the idea of fair distribution. This task allocation method not only promotes the full application of the task budget, but also enables more tasks to be successfully allocated.

Description of drawings

FIG. 1 is a flow chart of a method for assigning tasks for crowdsensing based on budget allocation according to the present invention.

Detailed ways

The present invention will be further described in detail below with reference to the accompanying drawings and examples, but the present invention is not limited to the following embodiments.

In FIG. 1 , the budget allocation-based crowdsensing task allocation method of this embodiment consists of the following steps:

(1) The set of perception tasks submitted by the task requester is set to Γ={τ ₁ ,τ ₂ ,τ ₃ }, task τ _i =(B _i ,Q _i ), where i∈{1,2,3,4} , τ ₁ =(4,75), τ ₂ =(8,240), τ ₃ =(5,110), τ ₄ =(6,130);

(2) Collect user set U={u ₁ , u ₂ , u ₃ , u ₄ , u ₅ , u ₆ }, q _j is the quality level of user u _j , where j∈{1,2,3,4} , q ₁ =3, q ₂ =5, q ₃ =3, q ₄ =2, q ₅ =3, q ₆ =2;

(3) Calculate the cost c _ij for the user u _j to complete the task τ _i , and determine the profit w _ij for the user u _j to complete the task τ _i ;

The cost c _ij for the user u _j to complete the task τ _i ,

c _ij =f(Q _i ,q _j )=5Q _i +10q _j (1)

The income w _ij of user u _j for completing task τ _i ,

w _ij =g(Q _i ,q _j )=Q _i +2q _j (2)

According to the above formulas (1) and (2), the costs and benefits of users u ₁ , u ₂ , u ₃ , u ₄ , u ₅ , and u ₆ to perform tasks τ ₁ , τ ₂ , τ ₃ , τ ₄ are calculated by matrices, respectively. express:

(4) Allocate the tasks in the sensing task set Γ according to the quality requirement Qi of the task τ _i and the quality level _{q j of} the user u _j . The specific allocation formula is as follows:

表示平台以往任务分配后的结余预算，为一个正实数，η∈(0,1)表示结余预算的利用率；In the formula, y _i indicates whether the task τ _i is successfully assigned, y _i =1 indicates that the task τ _i is successfully assigned, τ _i ∈Γ, y _i =0 indicates that the task τ _i assignment fails; x _ij indicates whether the task τ _i is assigned to the User u _j , u _j ∈ U, x _ij =1 indicates that task τ _i is assigned to user u _j , x _ij =0 indicates that task τ _i is not assigned to user u _j , δ indicates that all users participating in task τ _i The difference between the sum of the rewards and the total budget of the task,

Represents the balance budget after the platform's previous task allocation, which is a positive real number, and η∈(0,1) represents the utilization rate of the balance budget;

The above formula (3) is an integer programming problem, and in order to solve the problem efficiently, it is allocated according to the following method:

S1: Let the set Γ' be the set of tasks to be assigned, initially Γ'=Γ, for any task τ _i ,

表示平台以往任务分配后的结余预算，初始时Q′_i＝Q_i，B′_i＝B_i，令集合

为剩余的用户集合，集合U′为可选用的用户集合，初始时

集合

表示能执行任务τ_i的用户集合，初始

τ _i ∈Γ', let Q′ _i denote the remaining quality requirement value of task τ _i , and B′ _i denote the remaining budget of task τ _i ,

Represents the balance budget of the platform after the assignment of tasks in the past. Initially, Q′ _i =Q _i , B′ _i =B _i , set of orders

is the remaining user set, and the set U' is the optional user set.

gather

represents the set of users who can perform the task τ _i , the initial

是否成立，若成立，按照下式S2: Judgment set

Whether it is established, if so, according to the following formula

否则，停止；Find a specific task τ _i* , the specific task τ _i* is the task with the lowest quality requirement within the unit budget, the initial quality requirement value of the specific task τ _i* is Q′ _i* =Q _i* , the specific task τ _i* Remaining budget B′ _i* =B _i* , the set of users that can be selected for a specific task τ _i*

Otherwise, stop;

gather According to formula (4), find out a task τ _i* with the lowest quality requirement within the unit budget, obtain τ _i* =τ ₂ , the initial quality requirement value of the specific task τ ₂ is Q ₂ ′=Q ₂ =8, the specific task The remaining budget of τ ₂ B ₂ ′=B2=240, the set of users that can be selected for a specific task τ ₂

S3: Find a user u _j* that is closest to the quality requirement of a specific task τ _i* according to the following formula,

In the formula, c _i*j represents the cost paid by user u _j to perform the assigned specific task τ _i* , w _i*j represents the pure benefit brought by user u _j when performing the assigned specific task τ _i* , If it can be found, then turn to step S4; otherwise, delete this task in the task set Γ, and make y _i* =0, that is, the assignment of the specific task τ _i* fails, and then turn to step S2;

Obtain τ _i* =τ ₂ from step S2, find out u _j* =u ₂ according to formula (5), and turn to step S4;

S4: Determine whether the difference between the reward of the user u _j* performing the specific task τ _i* and the budget of the specific task τ _i* , that is, whether the following formula holds,

(c _i*j* +w _i*j* )-B′ _i* ≤δ (6)

In the formula, c _i*j* represents the total cost paid by user u _j * to perform the assigned specific task τ _i* , and w _i*j* represents the pure cost incurred by user u _j* when performing the assigned specific task τ _i* . If it is established, turn to step S5; otherwise, delete user u _j* in the optional user set U', and then turn to step S3 to find a new user;

The total cost c ₂₂ paid by the user u ₂ when performing the assigned specific task τ ₂ , the net benefit w ₂₂ brought by the user u ₂ when performing the assigned specific task τ ₂ , since c ₂₂ =90, w ₂₂ =18, B ' ₂ =240, δ = 25, then (c ₂₂ +w ₂₂ )-B' ₂ ≤δ is established, and turn to step S5;

S5: Determine whether the platform can use the balance budget to help a specific task τ _i* complete the assignment, that is, whether the following formula holds,

中，转向步骤S6；否则，应把用户u_j*从可选用的用户集合U'中删除，再转向步骤S3寻找新的用户；If so, add user u _j* to the set of users that meet the quality requirements of task τ _i*

In, turn to step S6; Otherwise, user u _j* should be deleted from the optional user set U', then turn to step S3 to find new users;

c₂₂+w₂₂＝90+18＝108，则公式(7)成立，将用户u₂加入集合

中，转向步骤S6；For user u ₂ , let n=0.8, since

c ₂₂ +w ₂₂ =90+18=108, then formula (7) is established, and user u ₂ is added to the set

, turn to step S6;

S6: delete the user u _j* from the selectable user set U', according to the formula Q' _i* =Q _i* '-q _j* and the formula B' _i* =B' _i* -(c _{i*j *} +w _i*j* ) update the values of Q′ _i* and B′ _i* , and then judge whether the quality requirements of the task τ _i* are satisfied, that is, whether the formula Q′ _i* ≤ 0 is established, if so, turn to step S7 ; If not established, turn to step S3 and continue to look for the user;

Delete user u ₂ in user set U', update the values of Qi ' and B _i ' _, Q ₂ '=Q ₂ '-q ₂ =3, B ₂ '=B ₂ '-(c ₂₂ +w ₂₂ ) =240-(90+18)=132, since Q ₂ '=3, the formula Q ₂ '≤0 does not hold, and turn to step S3;

转向步骤S4；In step S3,

Go to step S4;

In step S4, for user u ₁ , since (c ₂₁ +w ₂₁ )-B ₂ '=(70+14)-132=-48, δ=25, then formula (6) is established, and turn to step S5;

c₂₁+w₂₁＝70+14＝84，则公式(7)成立，将用户u₁加入集合

中，转向步骤S6；In step S5, for user u ₁ , it is judged whether formula (7) holds, because

c ₂₁ +w ₂₁ =70+14=84, then formula (7) is established, user u ₁ is added to the set

, turn to step S6;

In step S6, delete the user u ₁ in the user set U', update the values of Q _i ' and B _i ', Q ₂ '=Q ₂ '-q ₁ =0, B ₂ '=B ₂ '-(c ₂₁ +w ₂₁ )=132-(70+14)=48, since Q ₂ '=0, the formula Q ₂ '≤0 is established, and turn to step S7;

即为执行任务τ_i*的一个可行的用户集合，令y_i*＝1，即特定任务τ_i*成功分配，令x_i*j*＝1，即将任务τ_i分配给用户u_j*，

计算结余预算

令Γ'＝Γ'-{τ_i*}，

再转向步骤S2下一任务进行分配；S7: User Collection

is a feasible set of users to perform task τ _i* , let y _i* =1, that is, a specific task τ _i* is successfully assigned, let x _i*j* =1, that is, assign task τ _i to user u _j* ,

Calculate balance budget

Let Γ'=Γ'-{τ _i* },

Then turn to step S2 to assign the next task;

都令x_2j＝1，计算结余预算

令Γ'＝Γ'-{τ₂}，

转向步骤S402为下一任务进行分配；User set U ₂ ⁺ is a feasible set of users to perform task τ ₂ , let y ₂ =1, for any user

Let x _2j = 1, calculate the balance budget

Let Γ'=Γ'-{τ ₂ },

Turn to step S402 to assign the next task;

It should be pointed out that the task τ ₂ is successfully assigned when the user set U ₂ ⁺ that meets the quality requirements is found under the condition of sufficient budget;

按照公式(4)找出一个在单位预算内质量需求最低的任务τ_i*，求得τ_i*＝τ₃，初始特定任务τ₃的质量需求值Q₃'＝Q₃＝5，特定任务τ₃的剩余预算B₃'＝B₃＝110，特定任务τ₃可选用的用户集合

In step S2, the collection

According to formula (4), find out a task τ _i* with the lowest quality requirement within the unit budget, obtain τ _i* =τ ₃ , the quality requirement value of the initial specific task τ ₃ Q ₃ '=Q ₃ =5, the specific task The remaining budget of τ ₃ B ₃ ′=B ₃ =110, the set of users that can be selected for a specific task τ ₃

In step S3, find out u _j* =u ₃ according to formula (5), and turn to step S4;

In step S4, the total cost c ₃₃ paid by the user u ₃ when performing the assigned specific task τ ₃ , and the net benefit w ₃₃ brought by the user u ₃ when performing the assigned specific task τ ₃ , since c ₃₃ =55, w ₃₃ =11, B' ₃ =110, δ=25, then (c ₃₃ +w ₃₃ )-B' ₃ ≤δ is established, and turn to step S5;

c₃₃+w₃₃＝55+11＝66，则公式(7)成立，将用户u₃加入集合中，转向步骤S6；In step S5, for user u ₃ , since

c ₃₃ +w ₃₃ =55+11=66, then formula (7) is established, and user u ₃ is added to the set , turn to step S6;

In step S6, delete the user u ₃ in the user set U', and then update the values of Q _i ' and B _i ', Q ₃ '=Q ₃ '-q ₃ =5-3=2, B ₃ '=B ₃ '-(c ₃₃ +w ₃₃ )=110-66=44, since Q ₃ '=2, the formula Q ₃ '≤0 does not hold, and turn to step S3;

In step S3, u _j* =u ₄ , turn to step S4;

In step S4, for user u ₄ , since c ₃₄ =45, w ₃₄ =9, B′ ₃ =44, and δ=25, then (c ₃₄ +w ₃₄ )-B′ ₃ ≤δ is established, and turn to step S5 ;

中，转向步骤S6；In step S5, for user u ₄ , it is judged whether formula (7) holds, because c ₃₄ +w ₃₄ =45+9=54, then formula (7) is established, user u ₄ is added to the set

, turn to step S6;

In step S6, delete the user u ₄ in the user set U', and then update the values of Q _i ' and B _i ', Q ₃ '=Q ₃ '-q ₄ =2-2=0, B ₃ '=B ₃ '-(c ₃₄ +w ₃₄ )=44-54=-10, since Q ₃ '=0, the formula Q ₃ '≤0 is established, and turn to step S7;

都令x_3j＝1，计算结余预算

令Γ'＝Γ'-{τ₃}，

转向步骤S2为下一任务进行分配；In step S7, the user set U ₃ ⁺ is a feasible set of users to perform task τ ₃ , let y ₃ =1, for any user

Let x _3j = 1, calculate the balance budget

Let Γ'=Γ'-{τ ₃ },

Turn to step S2 to allocate the next task;

Although the budget of task τ ₃ is insufficient, because the platform uses the budget from previous tasks to make up for the task budget, task τ ₃ can find the user set U ₃ ⁺ that meets the quality requirements and successfully complete the assignment;

按照公式(4)找出一个在单位预算内质量需求最低的任务τ_i*，求得τ_i*＝τ₄，初始特定任务τ₄的质量需求值Q₄'＝Q₄＝6，特定任务τ₄的剩余预算B₄'＝B₄＝130，特定任务τ₄可选用的用户集合

In step S2, the collection

According to formula (4), find out a task τ _i* with the lowest quality requirement within the unit budget, obtain τ _i* =τ ₄ , the quality requirement value of the initial specific task τ ₄ Q ₄ '=Q ₄ =6, the specific task The remaining budget of τ ₄ B ₄ ′=B ₄ =130, the set of users that can be selected for a specific task τ ₄

In step S3, find out u _j* =u ₅ according to formula (5), and turn to step S4;

In step S4, the total cost c ₄₅ paid by the user u ₅ to perform the assigned specific task τ ₅ , and the net benefit w ₄₅ brought by the user u ₅ performing the assigned specific task τ ₅ , c ₄₅ =60, w ₄₅ =12, B' ₄ =130, δ=25, then (c ₄₅ +w ₄₅ )-B' ₄ ≤δ is established, and turn to step S5;

In step S5, for user u ₅ , since c ₄₅ +w ₄₅ =60+12=72, then formula (7) is established, and user u ₅ is added to the set , turn to step S6;

In step S6, delete the user u ₅ from the user set U', and then update the values of Qi ' and B _i ' _, Q ₄ '=Q ₄ '-q ₅ =6-3=3, B ₄ '=B ₄ '-(c ₄₅ +w ₄₅ )=130-72=58, since Q ₄ '=3, the formula Q ₄ '≤0 does not hold, and turn to step S3;

In step S3, u _j* =u ₆ , turn to step S4;

In step S4, for the user u ₆ , since c ₄₆ =50, w ₄₆ =10, B′ ₄ =58, δ=25, then (c ₄₆ +w ₄₆ )-B′ ₄ ≤δ is established, and turn to step S5 ;

c₄₆+w₄₆＝50+10＝60，则公式(7)成立，将用户u₆加入集合

中，转向步骤S6；In step S5, for user u ₄ , it is judged whether formula (7) holds, because

c ₄₆ +w ₄₆ =50+10=60, then formula (7) is established, and user u ₆ is added to the set

, turn to step S6;

In step S6, delete the user u ₆ from the user set U', and then update the values of Q _i ' and B _i ', Q ₄ '=Q ₄ '-q ₆ =3-2=1, B ₄ '=B ₄ '-(c ₄₆ +w ₄₆ )=68-60=8, since Q ₄ '=1, the formula Q ₄ '≤0 does not hold, and turn to step S3;

In step S3, since no new user can perform the task τ ₄ , the task τ ₄ cannot be assigned, so let y ₄ =0, delete this task in the task set Γ, and turn to step S2;

Task τ ₄ cannot complete the assignment because it cannot find a user set that meets the task quality requirements;

按照公式(4)找出一个在单位预算内质量需求最低的任务τ_i*，求得τ_i*＝τ₁，初始特定任务τ₁的质量需求值Q₁'＝Q₁＝4，特定任务τ₁的剩余预算B₁'＝B₁＝75，特定任务τ₁可选用的用户集合

In step S2, the collection

According to formula (4), find out a task τ _i* with the lowest quality requirement within the unit budget, obtain τ _i* =τ ₁ , the quality requirement value of the initial specific task τ ₁ is Q ₁ '=Q ₁ =4, the specific task The remaining budget of τ ₁ B ₁ '=B ₁ =75, the set of users that can be selected for a specific task τ ₁

In step S3, find out u _j* =u ₅ according to formula (5), and turn to step S4;

In step S4, the total cost c ₁₅ paid by the user u ₅ to perform the assigned specific task τ ₁ , the net benefit w ₁₅ brought by the user u 5 when the user u ₅ performs the assigned specific task τ ₅ , c ₁₅ =50, w ₁₅ =10, B' ₁ =75, δ=25, then (c ₁₅ +w ₁₅ )-B' ₁ ≤δ is established, go to step S5;

c₁₅+w₁₅＝60，则公式(7)成立，将用户u₅加入集合

中，转向步骤S6；In step S5, for user u ₅ , let n=0.8, since

c ₁₅ +w ₁₅ =60, then formula (7) is established, and user u ₅ is added to the set

, turn to step S6;

In step S6, delete the user u ₅ from the user set U', and then update the values of Q _i ' and B _i ', Q ₁ '=Q ₁ '-q ₅ =4-3=1, B ₁ '=B ₁ '-(c ₁₅ +w ₁₅ )=75-60=15, since Q ₁ '=1, the formula Q ₁ '≤0 does not hold, and turn to step S3;

In step S3, u _j* =u ₆ , turn to step S4;

In step S4, for user u ₆ , since c ₁₆ =40, w ₁₆ =8, B′ ₁ =15, and δ=25, then (c ₁₆ +w ₁₆ )-B′ ₁ ≤δ does not hold, and turn to step S3 ;

In step S3, since no new user can perform task τ ₁ , task τ ₁ cannot be assigned, so set y ₁ =0, delete this task in task set Γ, and turn to step S2;

The budget of task τ ₁ is insufficient and has exceeded the range that the platform can make up for the task budget, so the allocation cannot be completed;

则集合Γ中任务已全部分配完成；In step S2, the collection

Then the tasks in the set Γ have all been allocated and completed;

分配报酬r_j*，(5) According to the following formula (8), it is the user who performs the task τ _i* (τ _i* ∈Γ)

Distribution reward r _j* ,

计算得r₃＝55+11＝66，r₄＝45+9＝54，将报酬r₃和r₄分别付给用户u₃和用户u₄，其余任务及用户未分配，无报酬；当用户u_j*完成任务并获得报酬τ_i*后，将所有x_i*j*的值设为0，其中，τ_i*∈Γ，并将用户u_j*加入用户集合U中，支付报酬也可以在相应用户完成感知任务并上传感知数据后再进行。The set of users who perform task τ ₂ is U ₂ ⁺ , r ₁ =70+14=84, r ₂ =90+18=108 are calculated, and the rewards r ₁ and r ₂ are paid to user u ₁ and user u ₂ respectively, The set of users who perform task τ ₂ is

It is calculated that r ₃ =55+11=66, r ₄ =45+9=54, the rewards r ₃ and r ₄ are paid to user u ₃ and user u ₄ respectively, and the rest of the tasks and users are not assigned and unpaid; when the user After u _j* completes the task and gets paid τ _i* , set all x _i*j* values to 0, where, τ _i* ∈ Γ, and the user u _j* is added to the user set U, and the payment can also be done after the corresponding user completes the sensing task and uploads the sensing data.

Claims (1)

1. a kind of intelligent perception method for allocating tasks based on allocation of budget, which is characterized in that comprise the steps of:

(1) perception task set Γ={ τ that task requester is submitted is collected₁,...,τ_i,...,τ_n, i ∈ { 1 ..., n }, n is One limited natural number, task τ_i=(B_i,Q_i), B_iIt is to complete task τ_iMaster budget, be a limited positive real number, Q_iIt is Task τ_iQuality requirement value, be a limited positive integer；

(2) user's set U={ u is collected₁,...,u_j,...,u_mAnd the user set in user u_jCredit rating q_j, j ∈ { 1 ..., m }, m are a limited natural number；

(3) user u is calculated_jComplete task τ_iCost c_ij, and determine user u_jComplete task τ_iIncome w_ij；

(4) according to task τ_iQuality requirement Q_iWith budget B_iAnd user u_jCredit rating q_jTo in perception task set Γ Task is allocated, and specific distribution formula is as follows:

In formula, y_iIndicate task τ_iWhether at the distribution of work, y_i=1 indicates task τ_iAt the distribution of work, τ_i∈ Γ, y_i=0 indicates task τ_i Distribution failure；x_ijIt indicates whether task τ_iDistribute to user u_j, u_j∈ U, x_ij=1 indicates task τ_iDistribute to user u_j, x_ij =0 indicates not by task τ_iDistribute to user u_j, δ expression participation task τ_iThe sum of the remuneration of all users and task master budget Difference,

Unspent budget after indicating the previous task distribution of platform, is a positive real number, η ∈ (0,1) is indicated The utilization rate of unspent budget；

Formula (1) is an integer programming problem, is allocated by the following method:

S1: order set Γ ' is set of tasks to be allocated, Γ '=Γ when initial, for any task τ_i, τ_i∈ Γ ', enables Q '_i Indicate task τ_iRemaining quality requirement value, B '_iIndicate task τ_iResidual,

After indicating the previous task distribution of platform Unspent budget, Q ' when initial_i=Q_i, B '_i=B_i,

Enable set

For remaining user set, set U' is optional User set, when initial

Set

Expression can execute task τ_iUser set, initially

S2: judgement set

It is whether true, if so, according to the following formula

Find out a particular task τ_i*, particular task τ_i*It is specific initial for the task that the quality requirement in unit budget is minimum Be engaged in τ_i*Quality requirement value Q '_i*=Q_i*, particular task τ_i*Residual B '_i*=B_i*, particular task τ_i*Available user Set

Otherwise, stop；

S3: one is found out according to the following formula closest to particular task τ_i*The user u of quality requirement_j*,

In formula, c_i*jIndicate user u_jExecute distributed particular task τ_i*When the cost paid, w_i*jIndicate user u_jExecution divides The particular task τ matched_i*When brought net earnings if can find turn to step S4；Otherwise, it is deleted in set of tasks Γ This task, and enable y_i*=0, i.e. particular task τ_i*Distribution failure, turns again to step S2；

S4: judge user u_j*Execute particular task τ_i*Remuneration and particular task τ_i*Whether difference, that is, following formula of budget is true,

(c_i*j*+w_i*j*)-B′_i*≤δ

C in formula_i*j*Indicate user u_j*Execute distributed particular task τ_i*When the total cost paid, w_i*j*Indicate user u_j*It executes Distributed particular task τ_i*When bring net earnings, if set up if turn to step S5；Otherwise, in available user's set U' Delete user u_j*, turn again to step S3 and find new user；

S5: judge whether platform can utilize unspent budget

To help particular task τ_i*Complete distribution, i.e., whether following formula is true,

If so, then user u_j*Addition meets task τ_i*The user of quality requirement gathers

In, turn to step S6；Otherwise, It should be user u_j*It is deleted from available user's set U', turns again to step S3 and find new user；

S6: by user u_j*It is deleted from available user's set U', according to formula Q '_i*=Q_i*'-q_j*With formula B '_i*=B ′_i*-(c_i*j*+w_i*j*) update Q '_i*With B '_i*Value, then judge task τ_i*Quality requirement whether it is satisfied, i.e. formula Q '_i*≤ 0 is No establishment, if so, turn to step S7；If not, it turns to step S3 and continually looks for user；

S7: user's set

As execute task τ_i*A feasible user set, enable y_i*=1, i.e. particular task τ_i*At The distribution of work enables x_i*j*=1, i.e., by task τ_iDistribute to user u_j*,

Calculate unspent budget

It enables Γ '=Γ '-{ τ_i*,

The lower task of step S2 is turned again to be allocated；

(5) it according to task allocation result, calculates and pays user's remuneration r_j, for executing particular task τ_i*User u_j*It obtains Remuneration r_j*:

As user u_j*Complete particular task τ_i*And after obtaining remuneration, by all x_i*j*Value be set as 0,

τ_i*∈ Γ, And by user u_j*It is added in user's set U.

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