Computer System for Investment Planning on Dairy Farm

It is obvious that investment for a dairy farm can be done through different alternative plans. In this study the decision-making system of choosing the optimal plan from a number of alternatives is considered. The concept of such a system is known as Planning-Programming-Budgeting System (PPBS). There are 4 basic elements in PPBS, namely, (1) objective function, (2) resource restrictions, (3) various alternatives, and (4) comparison among the alternatives. The system developed in this study, is primarily base d on the concepts of PPBS and systems analysis. The optimal solution for each alternative is obtained by the linear programming technique, and the cost-benefit analysis method is used for comparing the results among the alternatives. The special character of the system is that, along with the optimal solution for each alternative, the mutual comparison of the results among various alternatives is performed systematically. The steps for finding the optimal investment plan a n d the flow of the system are illustrated as follows : (1) formulating the investment plan for each alternative, (2) making the input-output table to show the production technological coefficients, (3) finding the elements of resource restriction, (4) deciding the optimal operation level for each process by the linear programming method, (5) considering the appropriate discount rate and economic life of the project and evaluating the benefits and costs by discounting the stream of benefits andcosts at different points of time to get the present values, (6) using cost-benefit ratio as a criterion to decide the feasible plan, (7) checking whether there are still other alternatives ; if there are, start from the step 2 again, and (8) if all alternatives have already been considered, then looking at the marginal cost-benefit ratio and choose the most appropriate one. Based on the above principle, the system was developed by introducing a set of 5 alternative investment plans for a dairy farm. The farmer under consideration is deciding which plan he should adopt for the production, consisting of a certain method and tool as characterized by the different level of investment. The 5 alternative plans are : (I) hand milking, unimproved shed, power tiller, and hand cutting of forage crops, (2) hand milking, unimproved shed, power tiller, and forage cutter, (3) milker, improved shed, power tiller, and forage cutter (4) milker, improved shed, farm tractor, and mower, and (5) pipe-line milking system, improved shed, farm tractor, and mower. Under the assumption of the restricted resource of 72 ares rice field, 154 ares of upland field, 600 hours per month of farm labor, the alternative 4 is proved to be the optimal plan. The basic structure of the system is useful for the Batch Processing method and the Demand Processing method and the Time Sharing System (TSS), which are at present being widely used.酪農の投資計画にはいくつかの代替案がある。複数の代替案から最適な代替案を選択・決定するシステムについて考察する.システムの基本概念はPPBS(Planning-Programming-Budgeting System)である.PPBSには4つの基本項目がある.すなわち,(1)目標の設定,(2)盗源疑の制限,(3)複数の代替案,(4)代替案相互間の比較検討,以上4項目である.PPBSとシステムズ・アナリシスの概念をもとにしたシステムを構成し,線型計画法で各代替案の最適解を求め,費用便益分析で代替案相互間の比較検討を行う,このシステムの特徴は各代替案の最適解を求めるとともに,代替案相互の比較をシステマティックに行えることである.酪農の最適投資計画を例にして,システムの流れを示せば以下のようになる.1)投資計画を作成する.2)生濠技術を表わす投入産出表を作成する.3)制限要因を発見する.4)線型計画法を用いて各プロセスの最適稼働水準を決定する.5)割引率,計画期間を考慮し,便益と費用を推計する.便益と費用は時間的経過の中で発生する便益と費用を現在価値に価値換算したものである。6)実行可能案かどうか費用便益比率を判定基準として決定する.7)他の代替案を検討し,代替案があればステップ2へ続く.8)代替案がすべて考慮されると,限界費用便益比率を判定基準として最適案を採択する.以上の基本構想に基づくシステムを開発し,5つの代替案を前提に実行した.すなわち,第1案:手しぼり,従来の牛舎,耕耘機,手刈り,第H案:手しぼり従来の牛舎,耕耘機,草刈機,第III案:ミルカー,改良牛舎,耕耘機,草刈機,第IV案:ミルカー,改良牛舎,トラクター,モアー,第V案:パイフ。ライン,バーンクリーナー,改良牛舎,トラクター,モアーである.制限資源最を水田72アール,畑154アール,労働時間1カ月600時間とすれば,最適計画案は第IV案になる,システムの基木構造はバッチ処理(Batch Processing)およびコンピューターのより高度の利用技術であるディマンド処理(Demand Processing), TSS(Time Sharing System)にも汎用できるものと考える