The report is conposed two part.
The first part is summarised the many subjects on logistics (or physical distribution). whick Japanese emterprises have confronted, today.
The second part is point out that Japanese enterprises have accepted the systems on logistics (or physical distribation), by three survay output in recent year.

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So many algorithms of the shortest path problem with one objective have been proposed in the field of network theory. For decision making in some complicated systems such as transportation problems and large scale industrial systems, the shortest path for one objective is seldom optimal as a solution. In other words some problems are often with two objective functions or more. This idea is justified by the following example. Let's suppose the shortest path problem in a road network where both toll ways and conventional ways are available. The travel is very rapid but expensive when taking some toll ways while it is slow but inexpensive when not taking them. This problem has two different objectives, i. e., cost and time. Due to such complex systems theories and studies the multiobjective optimization are extensively tackled these days. In our study first the constrained k shortest paths problem is investigated that efficiently finds all feasible paths with their total lengths not violating a given length allowance. Next we propose an extended version of this class of problem, i. e., the constrained k shortest paths problem with two objectives. Two different types of algorithm are developed for each problem. Furthermore the bicriterion shortest path problem, that yields the pareto set of the shortest paths, is studied by using the algorithms for the constrained k shortest paths problem with two objectives. Finally some numerical results for these problems are provided by the algorithms implemented with FORTRAN77.

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This paper deals with the optimal routing for ocean liners. A fast service is essential for such liner services as well as for other transportation modes. An objective of the liner may be to minimize the turn-around time while visiting all the ports to be serviced, because the liner is to carry cargoes of multiple customers with different origin and destination pairs (OD pairs). This problem is the classical traveling salesman problem (TSP). Another objective to be considered should be to carry as much amount of cargoes as possible in the light of not only the high profit of the shipping company but also its role as a public transportation. However, due to the ship capacity, those two objectives seem contradict each other. In this study we introduce the TSP with the two objectives. In the problem we first construct a complete graph with nodes, each of which corresponds to a cargo OD pair. Then we use the classical TSP to find the shortest Hamiltonian cycle that carries the maximum amount of cargoes. Next we identify by a modified TSP algorithm all feasible routes whose lengths are not more than the length of the above Hamiltonian cycle. The maximum cargo amount that each feasible route can carry is calculated by an elaborated O (|K|²) multicommodity flow algorithm where K is the number of commodities. Finally we identify a set of pareto optima among all the feasible routes with their lengths and maximum cargo amounts. According to some computational experiments, our procedure for the problem performs quite well. Our problem is adaptable to a cyclic public bus transportation that has the same characteristics as ours.

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Logistics and Physical Distribution are the important elements of customer Service mix.Seeing that we discuss service. we must clear what serviceability is. However.for the serviceability there is not yet a strict definition that authorized scientifically and generally. While.as to the maintainability concerning with the serviceability.there is maintainability engineering concerning with reliability engineering.And it is just logistics resource that supports those of serviceability. maintainability.and reliability.in a broad sense.
From this points of view, serviceability, maintainability, and reliability are considered to be much affected by logistics resource availability. As a results, product and/or system availability depends on logistics availability too. In this sense, logisticsis is the important element of the dependability which is comprehensive concept including reliability, maintainability, serviceability, and availability.
Because the dependability of product and/or system cannot be assured unless the supportability with logistics resources are sure to keep. As a reliability concept in a wide sense. IEC (International Electrotechnical Commission) has defined the dependability in IEC300 below.
Dependability : The collective term used to describe the availability performance and its influencing factors : reliability performance. maintainability performance. and maintenance support performance.
On the aspects mentioned above, the logistics supportability to the customer is considered as the most important element, Accordingly, the dependability in physical distribution can be recognized as the comprehensive term to be used describing logistics availability characteristics and the elements affects it, such as;
(1) item demand rate characteristics.
(2) inventory service support rate characteristics, and
(3) reliability characteristics d maintainability characteristics of delivery service.
Then, the author considered the concept of physical distribution logistics de pendability consists of physical distribution logistics service and its system effectiveness, and can be measured and assessed its performance, and tried to define below.
Physical distribution logistics dependability
-Physical distribution logistics service :
All of the processes and activities that complete to deliver the available items which are required by customer on the given conditions within fixed time, and meet the customer's demand.
-System effectiveness of physical distribution logistics :
The probability that keeps available the items that are requested by a customer on the given conditions during fixed time, and meets customer's demand.
From these point of view, the author studied supportability (demand fill rate) in relation to reliability and maintainability, focussing on the support function which is the important aspect of logistics in a broad sense. The author formulated supportability and support rate as measurement of supportability, and as a result, created a supportability theory model. Furthermore, introducing that consideration, the author added new understanding on traditional inventory service rate which was the determinants of logistics availability on the logistics dependability mentioned above, and formulated with the model that uniformed traditional inventory model and supportability model on probability theory. Expanding the concept, this paper presents the formulation of new service rate and logistics dependability and its optimizing technique.

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