• Journal of Advanced Research in Ocean Engineering
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• v.3 no.2
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• pp.83-101
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• 2017

In this study, the added resistances of the large container ship in head and oblique seas are evaluated using a time-domain Rankine panel method. The mean forces and moments are computed by the near-field method, namely, the integration of the second-order pressure directly on the ship surface. Furthermore, a weakly nonlinear approach in which the nonlinear restoring and Froude-Krylov forces on the exact wetted surface of a ship are included in order to examine the effects of amplitudes of waves on ship motions and added resistances. The computation results for various advance speeds and heading angles are validated by comparing with the experimental data, and the validation shows reasonable consistency. Nevertheless, there exist discrepancies between the numerical and experimental results, especially for a shorter wave length, a higher advance speed, and stern quartering seas. Therefore, the accuracies of the linear and weakly nonlinear methods in the evaluation of the mean drift forces and moments are also discussed considering the characteristics of the hull such as the small incline angle of the non-wall-sided stern and the fine geometry around the high-nose bulbous bow.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.4
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• pp.805-811
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• 2003

System test is an important factor in the development process of good quality complex software in time, ensuring user requirements. Transaction processing module of database management systems schedules multiple transactions effectively and ensures that each transaction preserves data consistency. In this paper, we propose automatic functional testing techniques which ensure systematically that the implemented concurrency control function confirms to its requirements. The proposed testing technique tests functions of concurrency control module based on scenario without user intervention, and displays the result of functional testing. Finally, we utilize the proposed functional testing technique in the testing process of a database management system.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.11
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• pp.910-917
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• 2009

We have designed a new structures of Junction Field Effect Transistor(JFET) using SILVACO simulation to improve electrical properties and process reliability. The device structure and process conditions of Si control JFET(Si JFET) were determined to set cut off voltage and drain current(at Vg=0 V) to -0.46 V and $300\;{\mu}A$, respectively. Among many design parameters influencing the performance of the device, the drive-in time of p-type gate is presented most predominant effects. Therefore we newly designed SiGe JFET, in which SiGe layers were placed above and underneath of Si-channel. The presence of SiGe layer could lessen Boron into the n-type Si channel, so that it would be able to enhance the structural consistency of p-n-p junction. The influence of SiGe layer could be explained in conjunction with boron diffusion and corresponding I-V characteristics in comparison with Si-control JFET.

• Korean Institute of Interior Design Journal
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• v.14 no.2 s.49
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• pp.3-11
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• 2005

The subject of this paper is to find out the characteristics of Michael Graves' housing design. I collected the information of his designs and teamed his design language through his works on different time. I chose five actual housings for analysis which were built since 1960 when he have started his career. Though analysis of the exterior view, plane figures and the total arrangement photos, I could reached the conclusion. From analysis of this research I could figure out the characteristic of Michael Graves housing design as follows. During his whole working career $(1960\~present)$, his design style has went through distinctive characteristic changes that can be divided into: 1960s to early 1970s, mid and late 1970s, 1980s to as of now. 1960s to early 1970s, during this period his works implicated transparency, openness, consistency, complication, and contrast on space, abstraction, white-color and metaphor. mid and late 1970s, showed the white-color figure put together with geometrical structure and post-modernism styles such as ornamentation, natural and metaphor. 1980s to as of now, implicated ornamentation, natural features, historic background, interconnections, variety, symbolism and tradition.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.2
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• pp.297-309
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• 1998

Numerical parameters have been developed to diagnose L4/L5 disc patients during repetitive flexions and extensions. Electromyography(EMG) has been used to define the muscle excitation and movement cycle in this study. Twenty healthy subjects and twenty L4/L5 disc patients were recruited for the experiment. The subjective pain levels of patients were recorded as $3.7{\pm}1.6$ according to visual analogue scale where 10 was the maximum pain level. Variance ratio of motion cycle was suggested as a new parameter to examine the consistency of the trunk movement. The results indicated that the temporal EMG pattern such as peak time difference between Quadriceps and Hamstrings, the duration of coexcitation between Erector spinae and Rectus abdominis muscle pairs showed a statistically significant difference between healthy subjects and patients. Variance ratio of External oblique and Internal oblique also showed a statistically significant difference. It is expected that those results could be used for diagnosis by building a database for various back pain patients and healthy subjects. This method can eventually help physicians for early diagnosis and prevention of low back disorders.

• Environmental Engineering Research
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• v.23 no.2
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• pp.164-174
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• 2018

Corrosion of copper alloys (copper, bronze and brass) in soil was evaluated at ambient temperature using various methods such as electrochemical impedance spectroscopy (EIS), polarization curves and Scanning Electron Microscopy (SEM) coupled with Energy Dispersive Spectroscopy microanalysis measurements. Three equivalent circuits were separately used to interpret the obtained impedance spectra. The EIS measurements indicated that the polarization resistance of all electrodes increases with increasing the immersion time. SEM showed a presence of three layers of corrosion products with various composition and morphology covering each electrode. In addition, it was found that at 20% of moisture content the $R_p$ values and the current density of all electrodes in the studied soil give the following order: copper > bronze > brass. Good consistency between the data obtained from EIS and PP measurements was observed.

• Korean Institute of Interior Design Journal
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• v.17 no.1
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• pp.102-109
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• 2008

Recently, as emotional elements have been applied to many fields including marketing, architecture, and design, new understanding on and interest in sensibility are emerging. The sensibility, as opposite meaning to the reason, has been excluded from academic object, and researches in sensibility have been diversified for the meaning, scope, application methods and even application target of sensibility without consistency. This study aims to redefine meaning of sensibility by examining documents related to sensibility, and to examine the features of sensibility in design, especially in space design. Consequently, sensibility was defined to function as a filter which deals with numerous stimulative informations intuitively and uniformly while human gives significance to a stimulus. According to the examination on apparent features of sensibility and studies of sensibility engineering, the sensibility occurs not only by visual and physical stimulus but also by meaningful stimulus, and both are known to have mutual influence on each other. In space design, spaces of many purposes can be categorized into the spaces of routine and out of routine following the empirical time, and physical stimulus and interesting factor pursued by these spaces are inversely proportional. This study is meaningful insofar as it enabled to explain interaction between physical stimulus, meaning, and other factors within sensibility as a comprehensive concept by redefining its concept.

• IE interfaces
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• v.24 no.3
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• pp.210-219
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• 2011

The traditional AHP(Analytic Hierarchy Process) is to evaluate subjectively the alternatives in the view point of each of criteria and has been widely used at the fields of real world application. The AHP has some drawbacks that makes it difficult to keep the consistency of decision makers' input and take too long to get accurate results because of requiring lots of pairwise comparison between criteria and alternatives. This research is to propose and develop a Hybrid-AHP system for complementing the critical points of traditional AHP methodologies. This system gets the quantitative information as well as qualitative inputs as the comparative ones between criteria and alternatives. We use the input as various type of information such as quantitative values, 9-scale ratings, and fuzzy-based inputs. Finally, we applied the system to the case of choosing strategic industries. The case study have shown the use of various input methods saves processing time, and reduces the input burden of users.

• Geomechanics and Engineering
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• v.8 no.3
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• pp.415-440
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• 2015

In the present case study, High Strain Dynamic Testing of piles is conducted at 3 different locations of Kolkata city of India. The raw field data acquired is analyzed using Pile Driving Analyzer (PDA) and CAPWAP (Case Pile Wave Analysis Programme) computer software and load settlement curves along with variation of force and velocity with time is obtained. A finite difference based numerical software FLAC3D has been used for simulating the field conditions by simulating similar soil-pile models for each case. The net pile displacement and ultimate pile capacity determined from the field tests and estimated by using numerical analyses are compared. It is seen that the ultimate capacity of the pile computed using FLAC3D differs from the field test results by around 9%, thereby indicating the efficiency of FLAC3D as reliable numerical software for analyzing pile foundations subjected to impact loading. Moreover, various parameters like top layers of cohesive soil varying from soft to stiff consistency, pile length, pile diameter, pile impedance and critical height of fall of the hammer have been found to influence both pile displacement and net pile capacity substantially. It may, therefore, be suggested to include the test in relevant IS code of practice.

• International Journal of Automotive Technology
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• v.7 no.5
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• pp.603-608
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• 2006

As an important and relatively easy to implement technology for realizing Intelligent Transportation Systems(ITS), Adaptive Cruise Control(ACC) automatically adjusts vehicle speed and distance to a preceding vehicle, thus enhancing driver comfort and safety. One of the key issues associated with ACC development is usability and user acceptance. Control parameters in ACC should be optimized in such a way that the system does not conflict with driving behavior of the driver and further that the driver feels comfortable with ACC. A driving simulator is a comprehensive research tool that can be applied to various human factor studies and vehicle system development in a safe and controlled environment. This study investigated driving behavior with ACC for drivers with different driving styles using the driving simulator. The ACC simulation system was implemented on the simulator and its performance was evaluated first. The Driving Style Questionnaire(DSQ) was used to classify the driving styles of the drivers in the simulator experiment. The experiment results show that, when driving with ACC, preferred headway-time was 1.5 seconds regardless of the driving styles, implying consistency in driving speed and safe distance. However, the lane keeping ability reduced, showing the larger deviation in vehicle lateral position and larger head and eye movement. It is suggested that integration of ACC and lateral control can enhance driver safety and comfort even further.