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Software feasibility study and Project Development Plan
Tutorial
1. Knowledge Structure
This chapter briefly describes the task, steps and content of the Feasibility Study in the first phase of software development-software feasibility study and project development plan, as well as the content of the project development plan, this paper introduces the main methods of feasibility study, such as the system flowchart and cost-benefit analysis.

The knowledge structure in this chapter is 2-1.

Figure 2-1 Chapter 1 Knowledge Structure

2. Learning Methods
Understand the necessity of the feasibility study, master the task of the feasibility study, the specific steps of the feasibility study, and the main contents of the feasibility study report.

Mark the task of the feasibility study, the system flowchart, the basic concepts of cost-benefit analysis (investment recovery rate, payback period, and net income), and the basic content of the project development plan.

Understand the specific steps for conducting a feasibility study.

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(1) Feasibility Study

The purpose of the software feasibility study is to determine whether the software project can and is worth development at the minimum cost in the shortest time, the essence is to make a simplified and compressed demand analysis and design process in a more abstract way.

1. Basic Task

On the basis of the preliminary analysis and research, the project scale, objectives and restrictions are preliminarily determined, the logical model is established, and several alternative solutions are proposed, it also studies the feasibility of each scheme from the following three aspects:

① Technical Feasibility: evaluate the feasibility and technical risks of the project by comprehensively considering the functions, performance, restrictions and existing software and hardware resources of the project to be developed. The ambiguity of the preceding conditions makes the technical feasibility the most difficult to solve.

② Economic Feasibility: carry out cost estimation and benefit evaluation to determine whether the project is worth development. The study covers cost-benefit analysis, business strategies, costs and resources, and market prospects.

③ Social feasibility: whether there are infringement and other liability issues, whether the project operation mode meets and is feasible with the current user's management system, personnel quality, and operation mode.

2. Detailed steps

Determine the project scale and objectives: based on the full investigation and analysis, confirm the project scale, objectives and restrictions.

Study of running systems: including manual or old computer systems, study of their basic functions, costs and processing procedures, and study of functional requirements of new computer systems. On this basis, draw the high-level system flowchart of the existing system and review the flowchart.

Create a new high-level logical model for the system: Use data flow charts and data dictionaries to describe the flow and processing of data in the system.

Export and evaluate various schemes: different schemes for implementing high-level logic models are proposed from the technical perspective, and the schemes are evaluated based on technical, economic, and social feasibility.

Recommended feasibility plan: Determine feasible plans based on the above research and Describe feasible reasons.

Prepare a feasibility study report: organize the above results into relevant documents and submit them to the relevant departments for review.

3. Main content of the feasibility study report

The feasibility study report includes the following content: introduction, feasibility study premise, analysis of the existing system, technical feasibility analysis of the proposed system, economic feasibility analysis of the proposed system, and feasibility analysis of social factors, other options and conclusions.

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(2) system flowchart

A system flow chart is a traditional tool used to describe physical systems. It uses graphical symbols to describe the flow of elements and information between these elements. These graphical symbols represent processing (program module, etc.), input/output, data stream, document, storage, display, manual input, page feed connection, etc.

Figure 2-2 flowchart of the Product Sales Management System

The basic idea of the system flow chart is to select appropriate graphical symbols to describe every part of the system in the form of black boxes, such as programs, files, databases, tables, and manual processing processes. It describes the high-level logic model of the existing system in a general form, or it can be used to describe the physical model of the proposed system. Here, you should note that the system flow chart is different from the program flow chart introduced later. The latter is the control process for information processing.

We use the flowchart of the product sales management system to describe the flowchart. In the product sales management system, the data contained in the sales documents for the current day is the document serial number, product code, and (this ticket) sales quantity. After work, all valid daily sales orders should be used to update inventory accounts. If the inventory is found to be less than the minimum allowed inventory of the goods, write the request replenishment list. The system flowchart is given below, as shown in 2-2. Readers can refer to the textbooks to further understand the flowchart.

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(3) Cost-benefit Analysis

1. Purpose and Function

Cost-benefit analysis aims to evaluate the feasibility of developing a new software project from the perspective of economics. It compares the development cost of the system with the possible benefits, it is mainly used for project economic feasibility studies.

2. Analysis Method

There are two types of economic benefits: tangible and intangible. The key points are to master the following methods for analyzing tangible benefits.

① Time value of currency: the time value of currency is usually expressed by interest rate. Set the annual interest rate to I, and the existing income to P yuan. The amount of money obtained after N years is f = p * (1 + N * I ), that is, the value of P yuan after N years (excluding compound interest ). Otherwise, if you can earn RMB f after N years, the current value of the money is P = f/(1 + N * I ). This is the basic formula for benefit analysis.

② Payback period: it is usually used to measure the value of a development project. The payback period is to make the cumulative economic benefit equal to the time required for the initial investment cost. Obviously, the shorter the investment recovery period, the faster the project gets profit and the more worthy of development.

③ Net income: the difference between the system's cumulative economic benefits (equivalent to the current value) and investment within the entire life cycle is another indicator to measure economic benefits. If the net income is zero or less than zero, the project is not worth investing in development.

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(4) Project Development Plan

A Software Project Development Plan is a management document that includes the project overview, implementation plan, personnel organization, division of labor, and delivery period, the project management personnel control and manage the cost, progress, and resources of the Project accordingly.

1) Glossary

1. Feasibility Study

2. Technical Feasibility

3. Economic Feasibility

4. Payback Period

5. system flowchart

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(2) Fill in blank questions

1. The purpose of the feasibility study is not to develop a software project, but to study whether the project is ,.

2. The feasibility of the solution should be analyzed from the following three aspects :,,.

3. The technical feasibility should generally be considered, and ,,.

4. Benefit analysis first estimates the systems to be developed and then carries out with possible benefits.

5. Economic benefits can be divided into tangible and intangible benefits. The main metrics of tangible benefits are ,,.

6. Net income refers to the difference within the entire life cycle.

7. Economic feasibility should generally be considered in the following situations ,,,.

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(3) Single-choice questions

1. The feasibility study of the system is often conducted from different perspectives in the feasibility study of the software, and the study of the system from the functional perspective belongs.

A. Economic Feasibility B. Technical Feasibility

C. Operational feasibility D. Legal feasibility

2. in software engineering projects, the main problem that increases the productivity of software without increasing the number of participants is ().

A. Wait time for the work phase B. Complexity of the production prototype

C. Number of workstations required by participants D. difficulties in communication between participants

3. the purpose of developing a software plan is to make a reasonable assessment of the software to be developed as soon as possible. The task of the software plan is ().

A. Organization and Management B. ANALYSIS AND ESTIMATION

C. Design and Testing D. Planning and adjustment

4. The following metric indicators are not included in cost-benefit analysis ().

A. Time Value of currency B. Payback Period

C. Nature factors D. Net Income

5. arrows in the flowchart represent ().

A. Data Flow B. Control Flow

C. Call a link D. Build a link

6. The software feasibility study is essentially a () requirement analysis and design process.

A. Simplified and compressed B. Detailed

C. Thorough D. In-depth

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(4) Short answer questions

1. What is the task of the feasibility study?

2. What are the steps of the feasibility study?

3. What are the main contents of the feasibility study report?

4. What metrics can be used for cost-benefit analysis?

5. What are the content of the project development plan?

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(5) Application Questions

1. the development cost of designing a software is RMB 50 thousand and the service life is three years. The annual income for the next three years is estimated to be 2200 yuan, 24000 yuan, and 26620 yuan. The annual interest rate of a bank is 10%. Try to analyze the cost-benefit of the project to determine its economic feasibility.

2. A supermarket has a warehouse for storing commodities by category. The quantity of existing commodities in the warehouse and the inventory threshold values of each commodity are recorded in the inventory list main file. When the number of commodities in the warehouse changes, the main document of the inventory list should be modified in a timely manner. If the inventory of a certain commodity is less than the critical value of its inventory, it should be reported to the procurement department for ordering, it is required that an order report be sent to the purchasing department every day. Draw a flowchart of the system and briefly describe its work.

3. the workflow of the ATM to verify the customer's identity is as follows: the customer inserts the financial card into the ATM, the ATM reads the account number, and starts the account database to obtain account information through the "Confirm account" program, check the account. Then, the ATM asks the customer to enter the password and go to the "Read Password" program. Then, the password information is obtained through the "Confirm Password" program, which will enable the "Account" database to obtain the password information, check the password, and then send out the "correct password" information, perform the operations as required by the customer.

Draw a workflow for the customer identity verification part of the ATM.

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(1) Glossary

1. The feasibility study is to determine whether the software project can be developed and whether it is worth development at the minimum cost. The essence is to make a simplified and compressed demand analysis and design process in a more abstract way.

2. Technical feasibility is to estimate the technical risks of development projects under the existing technical conditions.

3. Estimate the development cost and evaluate the expected economic benefits in terms of economic feasibility.

4. the payback period is the time required for the cumulative economic benefit to be equal to the initial investment cost.

5. The system flowchart uses graphical symbols to express information flow between elements in the system.

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(2) empty answer

1. Is it worth developing whether the problem can be solved?

2. Technical feasibility economic feasibility social feasibility

3. developing techniques for the effectiveness of risky Resources

4. Comparison and trade-offs of development costs

5. Monetary time value investment recovery rate of pure income

6. Accumulative economic benefit investment

7. Cost-benefit analysis the costs and potential market prospects of resources required for long-term strategy development

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(3) answers to multiple choice questions

1. B 2. D 3. D 4. C 5. C 6.

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(4) Short answer

1. Feasibility study task: firstly, a brief analysis and study are required to preliminarily determine the project scale, objectives, constraints and restrictions. The analyst then analyzes the requirements briefly, abstracts the logical structure of the project, and establishes a logical model. Starting from the logic model, after the compression design, we can find several alternative solutions. We need to study the feasibility of each solution. There are three main considerations:

① Technical Feasibility: General considerations include the risk of development, that is, whether the designed system can meet the required functions and performance, the effectiveness of resources, and whether the development of related technologies is supported.

② Economic Feasibility: estimate the development cost and evaluate the benefits, and determine whether the project to be developed is worth investing.

③ Social feasibility: whether the project to be developed has any infringement problems, whether the operation mode is feasible within the user organization, and whether the existing management system, personnel quality, and operation mode are feasible.

2. ① determine the project scale and objectives.

② Research on the running system: Collect, study, and analyze the documents of the existing system, inspect the system in the field, access relevant personnel, and then describe the high-level system flowchart of the existing system.

③ Create a new high-level logical model of the system: Use data flow charts and data dictionaries to describe the flow and processing of data in the system.

④ Export and evaluate various solutions: export a number of high-level physical solutions, evaluate the technical feasibility, economic feasibility, and social feasibility, and obtain feasible solutions.

⑤ Recommended feasible solution: conduct cost-benefit analysis to determine whether the project is worth development. If it is worth development, what is the solution and the reasons for the feasibility of the solution are described.

⑥ Prepare a feasibility study report: Write the results of the above feasibility process into the relevant documents, that is, the feasibility study report.

3. ① Introduction: the purpose, project name, background, and terminology and references used in this document.

② Feasibility study prerequisites: Describe the functions, performance and basic requirements of the Development Project, the objectives to be achieved, various constraints, feasibility study methods, and the main factors that determine the feasibility.

③ Analysis of existing systems: describes the processing process and data process of the existing system, workload, various expenses, various types of professional technical personnel and quantity required, various types of equipment required, and the problems existing in the existing system.

④ Technical feasibility analysis of the proposed system: a brief description of the proposed system, a process and a data process, and advantages compared with the existing system. The impact of the proposed system on users is adopted, the impact on various equipment, existing software, development environment, and operation environment, on expenditures, and technical feasibility.

⑤ Economic feasibility analysis of the proposed system: describe various expenditures and benefits of the proposed system; income-to-investment ratio; and investment recovery period.

⑥ Social factor feasibility analysis: describes legal factors, analyzes contractual liabilities, patent rights infringement, copyright infringement, and other issues; describes the feasibility of user use, whether it meets the requirements of user administration, work system, and personnel quality.

7. Other options: explain the other options one by one, and explain the reasons for not recommending them.

Remark conclusion: it indicates whether the project can be developed, what conditions are required for development, and what changes are required for the project objectives.

4. ① investment recovery rate: Generally, the benefits obtained after the system is established for several years are converted into the current value and the cost required for the development system to compare and obtain the investment recovery rate.

② Payback period: the time required to make the cumulative economic benefits equal to the initial investment cost.

③ Net income: the difference between the cumulative economic benefits (converted to the current value) within the entire life cycle and investment.

5. ① Project Overview: describes the main work of the project, the functions and performance of the software, and the deadline and other conditions for the completion of the work undertaken by the user and the contractor, the name of the program to be delivered, the language used and the form of stored procedures, and the documents to be delivered.

② Implementation plan: Describes the division of tasks, the responsible person of each task, the project development progress, the project budget, the expenses of each stage, and the tasks to be completed at each stage, the Start Time and completion time of each task are displayed in a chart.

③ Personnel organization and division of labor: Personnel types, quantities, and composition structures are required.

④ Delivery deadline: the final completion date.

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(5) answers to Application Questions

1. After three years, 50 thousand of the value = 50000 × (1 + 3 × 10%) = 65000 RMB

3-year software profit = 22000 × (1 + 2 × 10%) + 24000 × (1 + 1 × 10%) + 26620 = 79420 RMB> 65000 RMB, so this project is profitable, economic and feasible.

2. Supermarkets use a high-end microcomputer to process the tasks of updating the inventory list master file and generating order reports. Every change in the inventory of goods becomes a transaction, which is input to the computer by the CRT terminal in the warehouse. The inventory list program in the system processes transactions, updates the master inventory list file stored on the disk, and writes necessary order information on the tape. Finally, the Report Generation Program reads the tape once a day and prints the order report, as shown in Figure 2-3 and figure 2-4.

Figure 2-3 workflow of a supermarket warehouse storing commodities by category

3.

Figure 2-4 workflow of an ATM

1 ● the feasibility study of the system is often conducted from different perspectives in the feasibility study of the software, and the study of the system from the functional perspective is.
A. Economic Feasibility B. Technical Feasibility
C. Operational feasibility D. Legal feasibility
2 ●. The purpose of developing a software plan is to make a reasonable assessment of the software to be developed as soon as possible. The task of the software plan is ().
A. Organization and Management B. ANALYSIS AND ESTIMATION
C. Design and Testing D. Planning and adjustment
3 ●. arrows in the flowchart represent ().
A. Data Flow B. Control Flow
C. Call a link D. Build a link
4 ●. The integrated test plan is developed in the outline design phase of the software life cycle and completed in the () phase.
A. Requirement Analysis B. Summary Design
C. Comprehensive Test D. Validation Test
5 ● In the detailed design stage, frequently used tools include ().
A. SC Diagram B. DFD Diagram
C. Pad diagram D. idef0 Diagram
6 ●. The database () design corresponds to the detailed design.
A. concept B. Logic
C. Physical D. Functions
7. Which of the following statements is false ().
A. the pad chart can be improved gradually. B. The pad chart may easily lead to unstructured program structures.
C. The pad diagram describes the hierarchical structure of the algorithm D. Pad diagram.
8 ●. The detailed design method for automatically generating programs is ().
A. flowchart B. IPO Diagram
C. Box Chart D. Pad chart
9 ●. The psychological characteristics of programming languages do not include ().
A. Ambiguity B. Portability
C. Simplicity D. Traditional
10 ●. The project application field does not include ().
A. Engineering Computing B. Artificial Intelligence
C. Data Processing D. Software Reuse

11 ●. 4gl languages can be used in () application fields.
A. Scientific Engineering Computing B. Data processing and database applications
C. Real-time processing D. Artificial Intelligence
12 ●. The first computer language in the world to be officially applied is.
A. fortran B. Assembly
C. Pascal d. c
13 ●. The language of 4gl is.
A. fortran B. FoxPro
C. Pascal d. c
14 ●. The main content of the preamble does not include ().
A. Module Interface B. Data Description
C. Functions of the module D. Data status
15 ●. The main content of functional comments does not include ().
A. Functions of the program segment B. Functions of the statement
C. Functions of the module D. Data status
16 ●. Factors that affect the input/output style do not include ().
A. Data status B. Communication Environment
C. User Experience D. Input/output devices
17 ●. Which of the following comply with the data instruction sequence specifications is ().
A. Full volume description, local volume description, type description, and constant description
B. Full volume description, local volume description, constant description, type description
C. Type description, constant description, full volume description, and local volume description
D. Constant description, type description, full volume description, and local volume description
18 ●. factors that determine Software maintainability do not include ().
A. Reliability B. Portability
C. Simplicity D. Efficiency
19 ●. What is productive in software maintenance activities is ().
A. Understand the functions of program code B. Modify the design
C. Write the program code D. Explain the Data Structure
20 ●. The use and development process of the prototype is called ().
A. Prototype period B. Prototype survival period
C. Prototype cycle D. None of the above statements