A markov chain is used to derive the models for determining the size of persons to be promoted and for conducting the sensitivity analysis of promotion probabilities. To compute the former case a future wastage rate is forecasted by using the double exponential smoothing method. The model for sensitivity analysis is used to simulate the impact of change in graded-size targets and hiring policy on the promotion probabilities.

Reusing software is a promising solution which overcomes the software crisis in the software development environment by improving the software productivity, reliability and maintainability. To develop software, some developers reuse existing softwares, but without an adequate design environment, software reuse would not be applicable. The purpose of this paper is to design and implement the X system, and measure empirically its resuability in the development phases. The development processes of the X system used a software reuse design guidelines within the Object-Oriented Design method and the Ada programming language. In order to measure the resuability, metrics was proposed and applied for each phase of development. The results of this paper address some reusability measurement that may be used as basic data when estimating the amount of reuse for a combined development project of military applications.

A new concept, namely the error discrimination of a code defined as the capability to not only detect errors from two distinct error sets but also to distinguish between them has been introduced in [SAKA 89a]. Consider $E_+\;and\;E_-$ as the two distinct error sets, namely the positive error set and the negative error set respectively. If a code C is not only capable of detecting any error e in {$E_+,\;E_-$}, but also able to identify the error set to which e belongs then the code is said to be an $E_+\;&\;E_-$ error discriminating code. The error discriminating property enables construction of unidirectional error detecting/correcting codes using asymmetric error control code. We derive here theory for asymmetric t error correcting and d error detecting codes. Furthermore, unidirectional error control code construction methods are introduced using asymmetric error control codes and $E_+\;&\;E_-$ error discriminating codes.

This research paper is aimed at developing an optimal strategy for finding espionage ship sent from North Korea. The optimal strategy developed here handles detection rate and probability that the espionage ship is in a certain specific sea area. A detection model is developed and an application problem is illustrated.

The concept of Algebraic-Coded Cryptosystem has been proposed recently but its application has not been developed yet. The primary object of this paper is to implement the Private-Key Algebraic-Coded Cryptosystem by using the primitive binary BCH codes. In the analysis of the cryptosystein, we find out the fact that there may exist other key pairs $S_i\;and\;P_i$ satisfying $G^*=S_{i},G_{s},P_{i}$ where $SG_{s}P$ is the original cryptosystem made by use of the systematic code generation matrix $G_{s}$.

A Geographic Information System (GIS) is a system designed to capture, store, manipulate, retrieve and display the data which are referenced to geographic location. With the progress of computer graphics technologies, GIS is now become applicable to microcomputer level. A prototype Sea Information System (SIS) applicable to microcomputer has been developed for serving informations related to naval operations in the special sea areas. This system includes GIS technologies, cartographic data captured through the tablet digitizer. which results immediate displaying on pen plotters. GIS provides users with menu-driven user interface for the retrieval of informations concerning military zones, patrol area of war ship, naval bases, radar sites and its search area, missile stations, and ships' current positions. The system is currently applicable to IBM PC/AT. Minimal hardware configuration consists 640k RAM, hard disk, and pen plotter or dot matrix printer.

여러 암호화 방식 중 비교적 비도가 높으며 표준화되어 있어 가장 널리 사용되고 있는 것이 DES이다. 그러나 DES의 안전성에 대하여 많은 문제점과 의문이 제기되어 왔으며 이들은 주로 DES S-Box에 관한 것이다. 이 S-Box의 구성은 평문과 암호문 사이의 상호관련성을 제거해주는 데 도움을 주지만 여기에 비밀통로가 숨겨져 있을 수 있는 가능성이 문제되고 있다. DES의 S-Box에 대한 이러한 문제점을 해결할 수 있는 방법의 하나는 0부터 15까지의 수를 무작위하게 순열하여 S-Box를 구성하는 것이다. 본 연구에서는 키에 의존하는 S-Box를 설계하며 아울러 이 변형된 DES를 수행할 수 있는 소프트웨어를 구축하여 변형된 암호화 방법의 안전성을 검토하고자 한다.

This paper presents a formalized methodology for conducting cost-effectiveness analysis on the ROK Navy's maritime patrol aircraft. The methodology involves a Delphi method application for determining the group of appraisal variables as well as their weight values in the area of aircraft effectiveness analysis, Life-cycle costing was employed to produce cost in terms of present worth values of all costs that occur over the common 20-year life cycle. A wide range of experts was selected so that their opinions could be effectively collected and synthesized to form the framework of the effectiveness model. Such a model development strategy provides easy acceptance of the analysis result and assure fairness of the analysis.

This study is concerned with the loss rate calculation for evaluating the safety of aircraft series. The objective of this study is to provide the estimation method of safety for the determination of aircraft series, when the aircraft is directly purchased off-the-shelf or co-produced. Especially, in case the initial operation capabilities of alternative aircrafts are substantially different, this research proposes the modified cumulative average method which can effectively estimate the safety of aircraft.