Monte-Carlo simulation technique has advantages over deterministic simulation in various engineering analysis since Monte-Carlo simulation can take into consideration of scattering of various design variables, which is inherent characteristics of physical world. In this work, Monte-Carlo simulation of steady-state cornering behavior of a truck with design variables like hard points and busing stiffness. The purpose of the simulation is to improve understeer gradient of the truck, which exhibits a small amount of instability when the lateral acceleration is about 0.4g. Through correlation analysis, design variables that have high impacts on the cornering behavior were selected, and significant performance improvement has been achieved by appropriately changing the high impact design variables.

The purpose of this study is to investigate the effect of acid fog on the rust formation behavior of weathering steel (SMA50) which is used in uncoated bridges. Weathering steel didn't form the passive film under the environment of acid fog(pH5,6), whereas the environment of distilled water formed the protective oxide film. Therefore, the construction of weathering steel under the environment extremely exposed to SOx and NOx which are the main compositions of acid fog is not adequate. Fatigue limits of weathering steel under acid fog environment are remarkably decreased as compared with environment of distilled water. The corrosive constituents in acid fog has piled up the corrosion products on specimen surface and generated the corrosion pits. Because of the high stress concentration arising at this corrosion pit, relatively low fatigue limits were obtained for acid fog specimens.

The non-dimensional heat loss from a thermally asymmetric triangular fin is investigated as a function of a ratio of upper and lower surface Biot numbers (Bi2/Bi1), the non-dimensional fin length and tip surface Biot number using the two-dimensional separation of variables method. The effect of fin tip surface Biot number on the variation of the non-dimensional temperature along the sloped upper and lower surfaces for the thermally asymmetric condition is presented. The relationship between the non-dimensional fin length and the fin tip surface Biot number for equal amount of heat loss is also discussed as well as the relationship between upper surface Biot number and tip surface Biot number for equal amount of heat loss.

3-D numerical studies are performed to investigate the effect of the air dam height and approaching air velocities on the pressure distribution of notchback road vehicle. For this purpose, the models of test vehicle with four different air dam heights are introduced and PHOENICS, a commercial CFD code, is used to simulate the flow phenomena and to estimate the values of pressure coefficients along the surface of vehicle. The standard $k-{\varepsilon}$ model is adopted for the simulation of turbulence. The numerical results show that the height variation of air dam makes almost no influence on the distribution of the value of pressure coefficient along upper and rear surface but makes strong effects on the bottom surface. That is, the value of pressure coefficient becomes smaller as the height is increased along the bottom surface. Approaching air velocity makes no differences on pressure coefficients. Through the analysis of pressure coefficient on the vehicle surface, one tries to assess aerodynamic drag and lift of vehicle. The pressure distribution on the bottom surface affects more on lift than the pressure distribution on the upper surface of the vehicle does. The increase of air dam height makes positive effects on the lift decrease but no effects on drag reduction.

To find the optimal solution as rapidly and exactly as possible with Nelder-Mead simplex algorithm, the present values of the reflection, expansion, contraction and/or shrink parameters of this algorithm are needed to be changed at appropriate time during the search process. The reflection parameter is selected in this study in order to be changed because reflection, expansion and contraction process can be simultaneously effected by only this parameter. Two independent indices for determining whether the present value of the reflection parameter of this algorithm should be changed or not during the search process are suggested in this study. Those indices were made of the equations of Nelder-Mead simplex algorithm's convergence criterion and Dennis-Wood's convergence criterion, respectively. It is appeared that the optimal solution can be find with smaller numbers of objective function evaluation than the original Nelder-Mead's one with fixed parameter when the those indices are used during the search process. and the more remarkable reduction effect of the number of an objective function evaluation can be obtained when the latter index is used.

Airbag systems have improved the occupant safety in reducing the injuries of driver and passenger during collisions. They have occasionally caused fatalities; especially to small occupant and children. Recent airbag related fatalities of children have raised serious concerns on how to evaluate the safety of children in various crash environments. This paper present the development of the 3-year-old human model. Child human model is composed of skin, skeleton and joints. The positions of joint and mass properties of body segments are calculated from ARB(Ariticulated Rigid Body) program GEBOD. To verify the developed human model, ROM simulation and OOP simulations are conducted.

Currently, many companies are trying to be more competitive by implementing the most appropriate software package called ERP (Enterprise Resource Planning). ERP can support the company's business process. A manufacturing execution system (MES) is an industrial software system, as well as a manufacturing management function in make-to-order and make-to-stock manufacturing environments. This paper presents an architecture of MES. This study develops MES to identify the functional requirements of loading & scheduling in the automobile industry. This study shows the effectiveness of the proposed MES, how to develop MES and interface with ERP package.

The shipbuilding scheduling has many possible alternatives because of its long time horizon and a lot of jobs, so it is required that the scheduling system can generate and search feasible alternatives rapidly. The scheduling in the assembly shop is initiated by allocating, namely loading, the assembly blocks to each shop. In this step, the resource capacities (such as available man/hour, available crane) of each shop must be considered. The result of loading without above consideration can make the scheduling result based on that infeasible or worse one. In this paper, we developed the optimal scheduling system of shipbuilding, specifically for loading and scheduling of assembly block, using ILOG Solver/Scheduler. ILOG Solver/Scheduler is a general-purposed commercial software which supports to find a feasible or optimal solution using object oriented technique and constraints satisfaction programming, given constraints and objectives. Also, in order to enhance the system performance, we conducted various experiments of ILOG search strategies. The experimental results showed that the impact of search strategies is significant.

The objective of this paper is to develop an efficient genetic algorithm (GA) to find a channel assignment method for minimum interference among the channels within reasonable time. The series of specific channel number is used as a representation of chromosome. We use minimum-channel-distance encoding scheme within the same cell to consider cosite channel interference (CSI) when chromosomes are generated. The cell base crossover is also used. This proposed method improves solution quality within limited time.

This paper deals with a case study on the process improvement and the layout design of a boiler factory with FactoryCAD. Firstly, two alternatives of job reallocation are suggested with the understanding of problems in current process. The layout planning for these new alternatives is carried out by simple procedure and the detailed analyses are performed by the aid of FactoryCAD program. The result shows that the new layout plan brings on about 10% reduction of travel distance. The utilization of FactoryCAD program can simplify the process of layout design.

When testing products before shipment to the customer, quality characteristics are measured to decide whether or not their values are between the specification limits. Unfortunately, this testing procedure can lead to incorrect decisions because of gauge error. That is, good products can erroneously be qualified as bad, and bad products as good, and this has consequences for producer's and consumer's risk. In cases of such as this, the compressed gauge limit can be used to achieve the desired product quality level dictated by the manufacturer or the customer. A compressed gauge limit is a limit set by the manufacturer on a test gauge that is tighter than the specification limit established by the customer. The compressed gauge limits should be set at levels to achieve the defect levels desired by the customer and simultaneously minimize the loss of good product that is rejected due to errors in the gauges. In this article, the models for determining the defect levels and the losses obtained by adding compressed gauge limits will be developed. A response surface model approach is utilized which allows an optimal operating condition to be generated relatively easily.

Much of domestic city is served by combined sewer system rather than separate sanitary or storm sewers. During wet weather, when the volume of sanitary sewage and storm water entering the combined sewers exceeds the system capacity, the system is designed to overflow at several designated CSOs. The objective of this research is to have grasp of characteristics of combined sewer runoff and to evaluate efficiently the intercepted volume of CSOs. During the wet weather in first rainfall, SS load at each site H-1, H-2, and H-3 were 600kg/event, 370kg/event, and 289kg/event, SS load at each site in second rainfall were 216kg/event, 113kg/event, and 37.2kg/event. EMCs at each site were 702mg/L, 816mg/L, 861mg/L in first rainfall and 99.9mg/L, 161.9mg/L, 103.6mg/L in second rainfall, respectively. First flush coefficients b at each site were 0.237, 0.166, and 0.151.

This research was performed to investigate the generation and physico-chemical characteristics of municipal solid wastes. The results were as follows: i) The generation rate and bulk density were 0.157 kg/cap/d and 147.8 g/L in residential zone, respectively. In non-residential zone, the generation and bulk density were 1.71 kg/cap/d and 85.6 g/L, respectively. Consequently, bulk density of non-residential zone was lower than that of residential zone. ii) The wastes consisted of 90% of combustibles and 10% of incombustibles in residential zone. And the wastes from non-residential zone was composed 85% of combustibles and 15% of incombustibles. iii) Water content was estimated at 47~50% in residential zone and restaurants. In non-residential zone, except restaurants, water content was in the range of 10~30%. Ash content was nearly 10% in overall zone.

This research was performed to investigate the COD removal efficiency and methane production in slurry-typed swine wastes using UASB(upflow anaerobic sludge blanket)reactor. The USAB reactor was operated from 0.8 through 3.3days of HRT in a range of 3 to 15 kg $TCOD/m^3/day$ of volumetric organic loading rate. The removal rate of TCOD was increased with the increase of the HRT. The removal rate of TCOD at an HRT over 2days, became greater than 68% with the methane contents being from 70 to 80%. Methane production rates were increased from 0.27 to $0.36m^3\;CH_4/kg$ CODrem. as HRTs were increased from 0.8 to 3.3days.

We prepared the nano-sized $TiO_2$ particles by the diffusion flame reactor and investigated the effects of several process variables on the generation and transport properties of $TiO_2$ particle. As the length from the tip of diffusion flame reactor increases, the size of $TiO_2$ particle increases by the coagulation between particles. The structure of $TiO_2$ particles prepared is almost found to be anatase. It was found that the $TiO_2$ particle size depends more largely on the change of reactor temperature than on the change of inlet $TiCl_4$ concentration. By the photo-degradation experiment of phenol and toluene with the prepared $TiO_2$ particles, we found that the photo-degradation efficiencies of phenol and toluene change, depending on the process variables such as size of $TiO_2$ photocatlysts, concentration of phenol or toluene. Degradation efficiencies of phenol and toluene was above 90% in our experiments in 60 minutes.

In this paper, a high performance current control strategy for a Brushless DC Motor is presented. The proposed strategy is based on the ramp comparison PI current control with the predictive voltage compensation. The proposed strategy is compared with the hysteresis current control strategy. The proposed method can improve the current waveforms, and it can reduce the torque ripples. So the proposed strategy is suitable to a high performance current control strategy for a Brushless DC Motor. The simulation and experimental results for a laboratory Brushless DC motor drive system confirm the validity of the proposed strategy.

In precision instrumentation system, an A/D conversion of signal conditioning has been always suffered from some problems ; offset and drift voltage with environmental situation. This paper suggests a method of reducing the offset voltage and the drift error from the A/D conversion hardware using analog signal switching technique with specific operational amplifier circuits. Also, we have designed a hardware active filter and a software digital filter with Auto Zero Tracking algorithm for better dignal process of the our proposed weighing system. Software technique was performed to obtain the stable data from A/D converter. As a result of our experimental works, the proposed system is expected to be used in the industrial field where a high precision measurement is required.

It becomes common to use computers to control electronic devices and security facilities in newly constructed buildings and house. There are many home application devices in the market which can be controlled by computers. But they are expensive and managed by specialized companies. This paper is focused on personal computers which are available in most homes and can be used to control home electronic appliances and home security facilities. We implemented a home automation server based on Linux. The standard parallel port of personal computer is used to connect sensors and actuators. Therefore, the cost of the server is very low. Moreover, the server is connected to Internet and anywhere we can control and monitor the home security facilities and home automation systems.

It is very important to detect and remove original sources of DOS (Denial of Service) attacks or connection oriented/connectionless attacks. In this paper, we implement a traceback system that does not require the reaction of routers and administrators and does not need log data. We bring in a traceback server and traceback agents in each network and use sniffing and spoofing schemes. Finally, the traceback server detects attacking hosts using information transmitted from traceback agents.

As the wireless communications are gradually developed, the higher frequency is demanded and the smaller the size of antenna shall be reduced by the wavelength of the operating frequency. However, the smaller the size of antenna becomes, the less the gain is obtained according to the frequency, so that a new attempt such as an array antenna has been examined to improve the characteristics. Also, for the convenience of communication, the omni-directional property is required. In this paper, two antennas system which is aligned in cross direction in tested and analyzed. The main scope is focused to get an appropriated distance between the two small antennas to get better properties. There are various ways of array arrangement, but in this study, it should be placed on the same PCB for easy implementation and the direction of each antenna are aligned to be a cross($90^{\circ}$) position. The study is carried out by comparing the radiation patterns mainly, and the theoretical expectation and the computer simulation are also executed. The final model is the folded IF-antennas system printed on PCB and the ideal dipole-antenna arrangement in also test to verify the possibility of our implementation. And it is finally proved by measuring experiments.

Autonomic nervous system play an important role of keeping our health as balancing homeostasis. But the abnormality of these abilities makes our presence be feeble. To obtain these information of body which helps for us to decide whether one is healthy or not, based on the study of Heart Rate Variability. In this paper, we presented HRV model and its processing steps to extract some information of human body. After that, some experimental results are presented in time-domain and frequency-domain.

In this paper, we discussed an effective VDSL frequency plan for symmetric 10MDSL service. The frequency plan 998 and plan 997 for asymmetric VDSL services have been not optimally designed for 10MDSL services. To obtain the reaches and data rates of 10MDSL, we proposed two frequency allocation schemes : Static method and dynamic method. We can select frequency bands with their fixed boundaries in static method while with their variable boundaries in dynamic method. To show the effectiveness of our proposed methods, we performed some simulations about plan 997 and plan 998, new static method, and new dynamic method. According to the simulation results, the proposed dynamic method can provide the best data rates and reaches for 10 Mbps symmetric VDSL services.

In this paper, we proposed separate queue scheme in each hierarchical cell for effective use of wireless channel. This method reduces the blocking rata of high speed mobile station's handoff in hierarchical cellular systems. Basically for the high speed mobile stations channels are allocated in macrocell and for the low speed mobile stations channels are allocated in microcell. In order to reduce the rate of forced handoff termination, some reservation channels are employed for the fast handoff calls in the macrocells. And the queue is located in each cell to be able to store handoff requests and takeback requests. The overflowed mobile station are able to perform takeback as soon as a corresponding channel is available.

This paper describes a design of an induction motor control system using a 2 degree-of-freedom PI controller to compensate the effects of disturbance without degrading tracking performance. On the basis of vector control principle, the control system is simulated by using the ACSL and implemented on a DSP system(TMS320C31). In designing the 2 DOF controller, we can tune the performance of either the tracking or disturbance rejection independently without affecting the other. With the experimental results, the 2 DOF controller has shown a better performance in command tracking and disturbance rejection than a conventional PI controller.

This paper is experimental and numerical research results of performing centrifuge model tests to investigate the geotechnical engineering behavior of slag compaction pile as a substitute of sand compaction pile. In order to find the geotechnical engineering characteristics of the soft clay and the slag used in centrifuge model experiments, basic soil property tests, consolidation test, permeability tests and triaxial compression tests were performed. For centrifuge model tests, slags with changing relative density were used and their bearing capacity, stress concentrations in between pile and soft clay, settlement characteristics, and failure modes were investigated. As a results of centrifuge model tests, it was found that the bearing, capacity of model was increased with increasing density of slag pile and general shear failures were occured. Miniature soil pressure gauges were installed on model pile and soft ground respectively and thus vertical stress acting on them were measured. Stress concentration ratio was found to be in the range of 2.0~3.0. Bearing capacity obtained from the model test with slag was greater than that from the model test with a sand having the identical layout to each other. Thus it was confirmed the slag was an appropriate substitution of pile for sand.

This research is experimental thesis to prepare the structural safety of the upper bridge for support type on tunnel and the effect of settlement. Unit weight test and uni-axial compression test have been performed to simulate the physical property of foundation on the tunnel. Tunnel model of slip form type for centrifuge model has been developed to performed the tunnel excavation while field stress is activated. And the support type of tunnel such as umbrella arch method and large diameter steel pipe reinforce method has been tested for the centrifuge model. After the analysis of experiment, results show that internal displacement of large diameter steel pipe reinforce method is smaller than that of the umbrella arch method.

The paper is to show the behavior of composit ground which is installed with sheet pile in soft soil improved by sand compaction pile. The results of load-settlement relationship, earth pressure, stress concentration characteristics, and final water content were obtained by centrifuge model test. Two cases of tests, installation of sheet pile on the corner and both side of the loading plate for the improved SCP ground which was designed twice of the footing width, were performed for the tests under the vertical and horizontal loading and both side of corner. Finite element program(CRISP) for sand compaction pile using elasto-plastic model and numerical analysis for soft soil using modified cam-clay constitutive equation were compared and analized with the results of model tests. The result of analysis show the increased bearing capacity of soil after, SCP and sheet pile was installed.

The sliding stability of monolithic vertical caisson of composite breakwaters is quantitatively analyzed by using a reliability model, FMA of Level II, in order to study the variation of sliding failure of caisson due to the occurrence of extreme waves exceeded deepwater design wave. The reliability index and several parameters in the wave pressure formula are inter- related to find out the effects of extreme wave exceeded design wave on the sliding failure of vertical monolithic caisson. The sliding failure of caisson seems to be largely increased as the heights and periods of extreme waves exceeded design wave increase, also depends directly on the water depth in front of the composite breakwaters. From the numerical simulations carried out with several kinds of extreme waves exceeded design wave which are assumed to be occurred during the service periods of breakwater, it is found that the effects of the wave height on the sliding failure of caisson may be more dominant than those of wave periods and angles of wave incidence.

The rational method of estimating peak flow is used largely for the simplicity. But the accuracy of rational method is not easy to estimate, because the rational method is analyzed by the deterministic point or view and the runoff coefficients of the rational method are proposed from other countries. In this study the rational method is analyzed by the probabilistic way to be a more reliable method. The runoff coefficient is regarded to parameter that changes the probabilistic rainfall to the peak flow. The runoff coeffient for each return period is analyzed to be a reliable index which is used to estimate the peak flow of ungauged natural catchments.

Optical fiber is indispensable for optical communication systems that transmit large volumes of data at high speed, but super precision technology in sub-micron units is required for optical axis adjustment. We developed the automatic optical fiber by image processing and automatic loading system. we have developed 6-axis micro stage system for I/O optical fiber arrays, the initial automatic aligning system software for a input optical array by the image processing technique, fast I/O-synchronous aligning strategy, the automatic loading/unloading system and the automatic UV bonding mechanism. In order to adjust the alignment it used on PC based motion controller, a $10{\mu}m$ repeat-detailed drawing of automatic loading system is developed by a primary line up for high detailed drawing. Also, at this researches used the image processing system and algorithm instead of the existing a primary hand-line up and fiber input array and waveguide chip formed in line by automatic.

In this thesis, a three degrees of freedom robot, which is able to provide sufficient precision for various robot researches, has been developed. The cable mechanism is used as a basic transmission of robot joints. Based on an optimal design strategy, link and joint parameters are determined and then overall geometry of the robot is designed. As an architecture of robot control, real time control system using real time linux and RtiC-Lab(Real Time Controls Laboratory) is developed. This system, written in C and based on Linux O/S, includes text editor, compiler, downloader, and real time plotter running in host computer for developing control purpose. Using these hardware and software, simple PD position control is implemented, the results shows the effectiveness of the system.