1. All appeals filed by the plaintiff and the defendant are dismissed.

2. The costs of appeal shall be borne by each party.

The purport of the claim and appeal is the purport of the appeal.

1. The reasons for the court's explanation concerning this case are as follows: the defendant's "Director" of the first instance court's decision No. 4 in Chapter 4 shall be deemed as "the original copy of the instant payment order"; and the original defendant's statement of the reasons for the first instance court's decision is as stated in the main sentence of Article 420 of the Civil Procedure Act, except where the original defendant added the judgment, which has been repeated or additionally claimed in the first instance court's trial, as stated in the following Paragraph 2.

2. Determination on addition

A. The plaintiff's assertion 1) The construction contract of this case aims at the production and installation of man-made plants, theme of which is the Daeama. Thus, in light of the nature of the contract, it constitutes a regular act that makes it impossible to achieve the purpose of payment after a certain period of time (Daemaman Pis) expires, but the defendant expressed his intent to refuse to waive the construction of this case to the plaintiff before the completion of the due date. Accordingly, the plaintiff notified the defendant of the cancellation of the construction contract of this case on the ground of the defendant's delay or refusal of performance. Even if the construction contract of this case was not cancelled due to the above notification, the construction contract of this case was lawfully rescinded upon the plaintiff's implied agreement to cancel the construction contract of this case. Accordingly, the defendant returned to the plaintiff the plaintiff an advance payment of KRW 30 million, and further, the defendant has no obligation to compensate the plaintiff for additional expenses of the completion of the construction work of this case due to the defendant's default. Thus, the defendant unilaterally did not cancel the construction contract of this case.