Especially in corporations of Japan, they must reconsider from the basics first, either (a) to inherit the style of traditional Japanese which seeking approval also by the directors of other departments, or, (b) to migrate to the system of obtaining an instantaneous decision only from the approval authority.
The following Business Process definition is a flow to obtain a judgement of approval directly from approver who is right above the proposer in the Organization tree, when a 'Proposal (Project)' was submitted to the Firm. That is, it's a flow diagram focused on speed which does not inherit the Japanese traditional style. Even though you can call it as a 'RINGI- system', of course, but we dare to call it a 'Project Approval system'. An excellent point is the mechanism that it automatically calculates the time it took to approve.
In addition, some people would like to give a Split Condition for the case that the proposer and the approver is the same person. However, there are different Roles and Characters in a person, so it is good enough to propose by oneself and to approve as well.
[Project Approval flow]