• IE interfaces
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• v.11 no.1
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• pp.183-190
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• 1998

This paper is concerned with the bicriteria vehicle routing problems with time window constraints(BVRPTW). The BVRPTW is to determine the most favorable vehicle routes that minimize the total vehicle travel time and the total customer wait time which are, more often than not, conflicting. We construct a linear goal programming (GP) model for the BVRPTW and propose a heuristic algorithm to relieve a computational burden inherent to the application of the GP model. The heuristic algorithm consists of a parallel insertion method for clustering and a sequential linear goal programming procedure for routing. The results of computational experiments showed that the proposed algorithm finds successfully more favorable solutions than the Potvin an Rousseau's method that is known as a very good heuristic for the VRPs with time window constraints, through the change of target values and the decision maker's goal priority structure.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.2
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• pp.60-67
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• 2017

A baggage handling system (BHS) in airport is an unified system for moving the passengers' baggage in designated time. Input baggage from the check-in counter travels to the baggage claim area or cargo handling terminal through this system. In particular, entryway BHS consists of conveyors, X-ray and sorters such as tilt-tray to send the baggage to departing airplane and it could have various problems for handling certain amount of baggage in restricted time such as baggage jamming at certain merge point. This causes systemic error such as delay of the time, omissions of the baggage and even breakdown of the equipment and inefficiency. Also the increasing maximum time of the baggage passing through the BHS could delay the flight schedule and finally decrease the service level. Thus, the algorithm for controlling the flow of the merge is essential to the system. The window reservation algorithm is the one of the most frequently used methods to control the merge configuration. Above all, the reserve location, so called reserve ahead point, that allocates the window is important for the performance of the algorithm. We propose the modified window reservation algorithm and the best reserve locations by changing the reserve ahead point in the induction conveyors. The effect of various reserve ahead points such as the capacity and utility of the system were analyzed and the most effective reserve ahead point combination was found. The total baggage processing time and the utilization of the tilt-tray are properly considered when choosing the optimal Reserve ahead point combination. In the layout of this study, the configuration of four conveyors merged into one tilt-tray is studied and simulation analysis is done by AutoMod(R), 3D simulation software. Through the simulation, the window reservation algorithm is effectively operated with the best combination of reserve ahead point which reduces the maximum baggage travel time.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.921-924
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• 1999

By controlling the pixels of a liquid crystal display (LCD) electronically, we fabricated a real-time moving window on a LCD, through which light passes. Using the moving window and hi-focusing lens, we suggested a non-mechanical spatio-angular multiplexed holographic memory system and demonstrated its feasibility through optical experiments. The principle of the proposed method and optical experimental results are also presented.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.179-182
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• 2011

The purpose of this study is to evaluate a defrost model for the possibility of defrosting on wheelhouse window and the heat capacity if defrosting nozzle by using the commercial CFD solver FLUENT. A detailed simulation model has been created which contains the defrosting nozzle, window and the interior/exterior forced convection boundary. In this numerical study, the heat and mass transfer coupled during defrosting and investigated the defrost time for different hot gas temperature, external wind speed and temperature condition.

• Journal of the Korean housing association
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• v.17 no.2
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• pp.125-134
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• 2006

The tightness of windows have devoted to the improvement of thermal insulation and energy saving in buildings. But it is known that this tightness causes some side effects such as low ventilation, low capacity to humidity and temperature control and these are not profitable for inhabitants. To act on these side effects, Korean traditional windows which are composed of Han-Ji(Koreand traditional paper) and Chang-Sal(Korean traditional wooden frame) have been studied to get a reasonable solutions for these problems. In this study, to compare the thermal and humidity control performance of current window(12 mm pair) and Korean traditional windows, frames which are made of existing window and Korean traditional windows are adapted to scale model house and then humidity and temperature of in and out of scale model house are measured and analysed. The results of this study are followings ; 1) When Korean traditional window charges 20cm(1/8 of total window area) from total window area, Han-Ji window has higher thermal insulation than that of existing window in daytime. There is the most big thermal difference when double faced with double-ply Han-Ji window is placed to mock-up house. In night-time, the temperature difference is very small so this means that Korean traditional window is good to cover direct sunlight in daytime and reduce the temperature of balcony. One faced with one-ply han-Ji window has the best humidity penetration performance among three type of Korean traditional windows. 2) When Korean window area enlarged to 40cm(1/4 of total window area), the function of 40cm width Han-Ji window is higher than that of 20cm's. This means that enlargement of Han-Ji window cover direct sunlight more and is more efficient in humidity penetration.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.4
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• pp.684-693
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• 2011

Measurement time delay in the transfer alignment is very important. It has been well known that the time delay degrades the alignment performance and makes some navigation errors on the transfer alignment of slave INS(SINS). Therefore there are many schemes to eliminate that time delay but the compensation technique through the estimation by Kalman filter through modeling the time delay as a random constant is generally used. In the case of change over measurement time delay or the large measurement time delay, estimation performance in the existing compensation technique is degraded because model of time delay is not correct any more. In this paper, we propose the method to keep the time delay almost constant even though in the abnormal communication state and very small through feedback compensation using double buffer. Double buffer consists of two moving window to temporarily store measurements from master INS and slave INS in real time.

• Journal of the Korean Operations Research and Management Science Society
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• v.34 no.1
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• pp.153-165
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• 2009

This paper apollos an ant colony system (ACS) for the vehicle routing problem with time window (VRPTW). The VRPTW is a generalization of the VRP where the service of a customer can begin within the time windows defined by the earliest and latest times when the customer will permit the start of service. The ACS has been applied effectively in geographical environment such as TSP or VRP by meta-heuristic that imitate an ant's biologic special duality in route construction, 3 saving based ACS (SB-ACS) is introduced and its solution is improved by local search. Through iterative precesses, the SB-ACS is shown to drive the best solution. The algorithm has been tested on 56 Solomon benchmarking problems and compared to the best-known solutions on literature. Experimental results shows that SB-ACS algorithm could obtain food solution in total travel distance minimization.

• Journal of Power System Engineering
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• v.9 no.2
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• pp.73-80
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• 2005

Both theoretical and experimental investigations were conducted to analyze defrosting behavior of a window heater operating in the low outdoor temperature($-20^{\circ}C$). To achieve this purpose, first a warm-chamber experiment($23^{\circ}C$) was performed to measure inner and outer surface temperature of the rear window(heated by the electric heater supplying 195 W) as functions of both time and position. Secondly, a cold chamber experiment was made to continuously record defrosting process of the frosted window. From the comparisons of the two experimental results, it was found that there was a similarity between the spatial distributions of both temperature and remaining frost. Thus, the temperature data from the warm-chamber experiments can be utilized to predict an expected zone covered with remaining frosts, and this approach can also be adopted in the inspection process in order to economically guarantee optimized performance of the window heater. Finally, an analytical model based on one-dimensional, steady-state heat transfer theories was proposed and successfully predicted the outer surface temperature of the rear window surrounded by cold air($-20^{\circ}C$) for the given operating conditions(heater power, inside and outside heat transfer coefficients, and surrounding air temperature, etc.).

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.12
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• pp.2298-2305
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• 2010

The paper presents the Model Based Design(MBD) method which design and verify control algorithm for safety power window. Safety power window are required to work together with the anti-pinch function and have to meet FMVSS118 S5 requirements and equivalent ECC requirements. To meet the requirements, this paper presents the establishment of SILS and RCP environments. The design process can reduce time and support more performance-assured design. As a result of study, it met the regulations and achieved reaction force that close to common products.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.6A
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• pp.550-557
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• 2007

We predict a context of various structures by using Bayesian Networks Algorithms, Three-Dimensional Structures Algorithms and Genetic Algorithms. However, these algorithms have unavoidable problems when providing a context-aware service in reality due to a lack of practicality and the delay of process time in real-time environment. As far as context-aware system for specific purpose is concerned, it is very hard to be sure about the accuracy and reliability of prediction. This paper focuses on reasoning and prediction technology which provides a stochastic mechanism for context information by incorporating various context information data. The objective of this paper is to provide optimum services to users by suggesting an intellectual reasoning and prediction based on hierarchical context information. Thus, we propose a design of user location prediction algorithm using sequential matching with n-size flexible window scheme by taking user's habit or behavior into consideration. This algorithm improves average 5.10% than traditional algorithms in the accuracy and reliability of prediction using the Flexible Window Scheme.