• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.10
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• pp.1158-1162
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• 2009

Fatigue limit of the copper film coated by Sn was estimated using Goodman diagram and Gerber diagram. To obtain the high cycle fatigue life curve, S-N curve, of the film, the high cycle fatigue test was carried out by applying the constant amplitude load to the film specimen with three different stress ratio of 0.05, 0.3 and 0.5 and the frequency of 40 Hz at room temperature in air. The free-standing film specimen 15.26${\mu}m$ thick was fabricated by etching process. The fatigue limits and S-N curves at the respective stress ratios were determined from the experimental works. It was shown that the S-N curves were dependent on the stress ratio and the fatigue limit was increased with decreasing the stress ratio. The dependency of the fatigue behavior was presented in empirical relationship. Using these relationships, the fatigue limit was predicted.

• Korean Journal of Human Ecology
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• v.15 no.1
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• pp.129-139
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• 2006

The purpose of this study is to compare the hairstyles between Korean and Australian women, who have different individual hair characteristics, social backgrounds, and culture from each other. Data were collected through a survey of 208 Australian females and 392 Koreans. Frequency analysis, t-test, and two-way ANOVA were used to analyze the data. The results are as follows: Korean and Australian women maintain a hairstyle for six months or less in most of the cases. They preferred a hairstyle with bang, and the elderly especially a shorter hair length. Choosing their hairstyles depended on such factors as hair length, dyeing, form of face, harmony with clothing, and social status. There was no difference, however, in a preferred hair length. Korean women possessed brown and black hair colors in a descending order, whereas Australians light blonde and brown in a descending order as well. There was a big difference in the preference for a permanent wave. Korean women preferred to give a volume or curl to their hair, while Australians wanted to have a straight hair. According to the study on a hairstyle behavior, it was found that there were differences in fashion and individuality between two countries and also in dependency among age groups, whereas no differences existed in beauty.

• Smart Structures and Systems
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• v.19 no.6
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• pp.601-614
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• 2017

In this work, free vibration analysis of size-dependent functionally graded (FG) nanoplates resting on two-parameter elastic foundation is investigated based on a novel nonlocal refined trigonometric shear deformation theory for the first time. This theory includes undetermined integral variables and contains only four unknowns, with is even less than the conventional first shear deformation theory (FSDT). Mori-Tanaka model is employed to describe gradually distribution of material properties along the plate thickness. Size-dependency of nanosize FG plate is captured via the nonlocal elasticity theory of Eringen. By implementing Hamilton's principle the equations of motion are obtained for a refined four-variable shear deformation plate theory and then solved analytically. To show the accuracy of the present theory, our research results in specific cases are compared with available results in the literature and a good agreement will be demonstrated. Finally, the influence of various parameters such as nonlocal parameter, power law indexes, elastic foundation parameters, aspect ratio, and the thickness ratio on the non-dimensional frequency of rectangular FG nanoscale plates are presented and discussed in detail.

• Journal of KIISE:Software and Applications
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• v.33 no.5
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• pp.470-480
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• 2006

The longer the input sentences, the worse the parsing results. To improve the parsing performance, many methods about long sentence segmentation have been reserarched. As an isolating language, Chinese sentence has fewer cues for sentence segmentation. However, the average frequency of comma usage in Chinese is higher than that of other languages. The syntactic information that the comma conveys can play an important role in long sentence segmentation of Chinese languages. This paper proposes a method for classifying commas in Chinese sentences according to the context where the comma occurs. Then, sentences are segmented using the classification result. The experimental results show that the accuracy of the comma classification reaches 87.1%, and with our segmentation model, the dependency parsing accuracy of our parser is improved by 5.6%.

• Proceedings of the IEEK Conference
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• 2002.06b
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• pp.165-168
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• 2002

As the demand for higher data-rate chip-to-chip communication such as memory-to-controller, processor-to-processor increases, low cost high-speed serial links\ulcorner become more attractive. This paper describes a 0.25-fm CMOS 1.6Gbps/pin 4-level transceiver using Stub Series Terminated Logic for high Bandwidth. For multi-gigabit/second application, the data rate is limited by Inter-Symbol Interference (ISI) caused by channel low pass effects, process-limited on-chip clock frequency, and serial link distance. The proposed transceiver uses multi-level signaling (4-level Pulse Amplitude Modulation) using push-pull type, double data rate and flash sampling. To reduce Process-Voltage-Temperature Variation and ISI including data dependency skew, the proposed high-speed calibration circuits with voltage swing controller, data linearity controller and slew rate controller maintains desirable output waveform and makes less sensitive output. In order to detect successfully the transmitted 1.6Gbps/pin 4-level data, the receiver is designed as simultaneous type with a kick - back noise-isolated reference voltage line structure and a 3-stage Gate-Isolated sense amplifier. The transceiver, which was fabricated using a 0.25 fm CMOS process, performs data rate of 1.6 ~ 2.0 Gbps/pin with a 400MHB internal clock, Stub Series Terminated Logic ever in 2.25 ~ 2.75V supply voltage. and occupied 500 * 6001m of area.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.10
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• pp.78-85
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• 2004

The particle amount monitoring technique using ultrasound is proposed to determine the proper maintenance time of the filter in the supply process of pure gas in the unit of oxygen plant. There are advantages that it is adaptable in high temperature and high pressure, and it is not disturbed by being exposed in the gas flow, and it can be implemented very economically. The applicability of the ultrasonic technique is pre-studied through the theoretical analysis for the dependency of attenuation of ultrasonic wave on the particles in the gas flow. For the purpose, absorption, scattering and dispersion models are considered, and the attenuation by absorption and the change rate of the propagation speed are calculated fur the specific range of particle size and the ultrasonic wave frequency. It was expected by simulation that the absorptive attenuation by particles was the most sensitive to the change of particle amount. The experimental result showed high correspondence with the theoretical expectation so that this ultrasound attenuation measurement was proved to be highly effective for monitoring the amount of floating particles in the gas flow.

• Journal of the Optical Society of Korea
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• v.17 no.3
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• pp.262-268
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• 2013

We study the focusing properties of a two-dimensional square-lattice photonic crystal (PC) comprising silica and germanium partitioned cylinders in air background. The finite difference time domain (FDTD) method with periodic boundary condition is utilized to calculate the dispersion band diagram and the FDTD method incorporating the perfectly matched layer boundary condition is employed to simulate the image formation. In contrast to the common square PCs in which the negative refraction effect occurs in the first photonic band without negative phase propagation, in our suggested model system, the frequency with negative refraction exists in the second band and in near-infrared region. In this case, the wave propagates with a negative phase velocity and the evanescent waves can be supported. We also discuss the dependency of the image resolution and its location on surface termination, source location, and slab thickness. According to the simulation results, spatial resolution of the proposed PC lens is below the radiation wavelength.

• Health Policy and Management
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• v.6 no.2
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• pp.149-189
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• 1996

The aims of this study were to find out present situation of self-medication, and to explicate the factors affecting self-medication propensity. To explicate empirically the factors affecting self-medication propensity, a model containing five groups of determining factors such as attitudinal, behavioral, knowled해, and need of health care factors, and demographic factors were developed. Data were collected from 647 residents in Pusan and Kyungnam using the self-administered questionnaire. The major reslts obtained were as follows: First, self-medication was 32% of all utilization of pharmacy. The drugs used for self-medication most commonly were analgesics(16.2%), followed by antacids and stomachics(14.2%), dermatologic preparations(13.1%), tonics and drinks (12.6%). Second, the sources from which people obtained drug information at self-medication were label of the container(50.8%), pharmacist(32.4%), self-decision or lay person(16.8%). The experience of side effect was 10.6% of all self-medication and how people cope with was withdrawal(59.0%), consultation by pharmacist or doctor(35.9%). Third, the results of ANOVA showed a statistically significant relationship between self-medication propensity and 3 demograpic factors, such as sex(p<0.10), age(p<0.10) and job(p<0.05). Forth, the results of multiple regression analysis showed a statistically significant positive relationship betwee self-medication propensity and satisfaction of previous self-medication, knowledge of drug, drug dependency, the frequency of doctor visiting, confidence in drug advertisement, tendency toward self-treatment of the family, and job. And it showed negative relationship between self-medication propensity and confidence in the medical profession, and health behavior. The model explained 29.5% of the variance in self-medication(p<0.001).

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.4
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• pp.1-9
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• 2000

As the speed of the paper machine and printing press increases, the dependency of the production efficiency upon the frequency of web break increases. It is believed that flaw or crack that presents in paper is one of the most important for web break. Runnability of papers on the paper machine could be evaluated by measuring fracture toughness. In this paper the effect kof beating and pressing on the runnability was investigated using handsheets made from softwood bleached kraft pulp beaten to different freeness. Pressing pressure was also varied to obtain different levels of sheet consolidation. Density, tensile strength, and J-integral of the handsheets were evaluated. For measuring J-integral either a single specimen method or RPM method was employed. Results showed that the density and tensile strength were improved as beating and pressing increased because of increased interfiber bonding. J-integral increased with beating until the CSF reached 400mL. No significant difference in J-integral, however, was observed afterward with the increase of beating. And it appeared to be due to acceleration of the stress concentration around the crack that exists on the fiber wall of the sheet when cracks exists.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.46 no.3
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• pp.248-256
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• 2010

Acoustic side-aspect target strength (TS) of living Japanese anchovy (Engraulis japonicus) was measured at 120kHz during in situ experiments. The data were collected by lowering and horizontally projecting the splitbeam transducer into the anchovy school. For analysis and interpretation of the side-aspect TS data, acoustic theoretical model, based on the fish morphology, and dorsal-aspect TS data were used. Total length of the anchovy ranged from 6.6 to 12.8cm (mean length 9.3cm). The side-aspect TS distributed between -40 and -55dB, has an obvious length dependency. The mean side-aspect TS of the anchovy was -47.8dB, and the TS was about 2dB higher than mean TS generated from dorsal-aspect measurements. With reference to maximum TS, the results of the side-aspect TS were distributed within the range of the theoretical and dorsal-aspect TS. Apparently these tendency indicates that side-aspect TS measured from the study is useful data. These in situ measurements of side-aspect TS can be applied to improve acoustic detection and estimates of the anchovy, and is necessary to measure with a various frequency and length for making enhance data.