• Journal of applied mathematics & informatics
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• v.12 no.1_2
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• pp.307-312
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• 2003

In this paper, a special incidence structure is designed based on (v, k+1, 1)-configuration, a subset of symmetric balanced incomplete block design, where ν = k$^2$+ k + 1. The time complexity required for desinging this incidence structure is O(equation omitted).

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.52-52
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• 2010

Amorphous carbon films have a variety of potential applications. In most such applications film properties are crucial and highly dependent on the film growth conditions. We here investigate the atomic structure of the films, which is generated at various incidence angles, using the classical molecular dynamics. Varying incidence angle of the deposited carbon atoms, different level of sp hybridization and porosity of the film are captured in our model. As the incidence angle becomes glancing, subplantation of the deposited carbon in vertical direction is significantly reduced, rather bouncing back of the incident carbon with slight modification of surface structure is mainly occurred at the early stage of the film growth. As the surface becomes rougher, shadowing effect at these glancing incidences also becomes more significant, which tends to cause asymmetrical and columnar structure. We describe incidence angle dependence of the evolution of the atomic structure of the film and its corresponding properties.

• 유체기계공업학회:학술대회논문집
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• 2003.12a
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• pp.55-62
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• 2003

This paper describes the effect of the incidence angle on the turbulence structure in the wake of a turbine rotor blade at the low inlet free-stream turbulence level. For three incidence angles of -5, 0 and 5 degrees, mid-span energy spectrum as well as mid-span profiles of mean velocity magnitude and turbulence intensity are reported at three downstream locations in the wake. Vortex shedding frequencies are obtained from the energy spectrum. The result shows that as the incidence angle changes from-5 to 5 degrees, the boundary layer on the suction surface tends to be thickened, which results in widening of the wake. Strouhal numbers based on the shedding frequencies have a nearly constant value of 0.3, independent of tested incidence angles.

• Journal of Electrical Engineering and information Science
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• v.3 no.1
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• pp.80-85
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• 1998

A theoretical calculation and an optical measurement method of normal-incidence absorption are proposed. By using a waveguide structure, optical interference and the problem of low level signal can be avoided in the measurement of normal-incidence absorption. The oscillator strength of intersubband absorption for a waveguide structure is calculated in Si(001), Si(110), and Ge(001) quantum wells. The polarization angle dependence of the measured and the calculated absorption strength can be obtained with the same waveguide structure, and be compared after normalization. The normal-incidence absorption in Si(110) and Ge(001) quantum wells is shown theoretically, and can be observed in the optical measurement using waveguide structures at the polarization angle of 90$^{\circ}$.

• Journal of the Semiconductor & Display Technology
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• v.2 no.4
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• pp.23-26
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• 2003

The general users find difficulties in using ellipsometers. Thus, the object of this study is to construct an ellipsometer with simple operation principle. We developed an ellipsometer which does not require alignment and calibration before measuring sample. A basis structure model after rotating a compensator spectroscopic ellipsometry, the fixed incidence angle at $70^{\circ}$. This ellipsometer does not demand calibration, because the plane of incidence is not changed due to the novel sample holder structure. The results for various standard samples were compared with those from conventional RCSE to test the performance of this instrument. Also repeated measurements were performed to test the precision of the calibration coefficient in a plane of incidence fixed.

• Earthquakes and Structures
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• v.17 no.4
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• pp.387-398
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• 2019

On the basis that ground motions may arrive at a structure from any horizontal direction and that different directions of seismic incidence would result in different structural dynamic responses, this paper focuses on orienting the crucial seismic incidence of transmission tower-line systems based on the wavelet energy method. A typical transmission tower-line system is chosen as the case study, and two finite element (FE) models are established in ABAQUS, with and without consideration of the interaction between the transmission towers and the transmission lines. The mode combination frequency is defined by considering the influence of the higher-order modes of the structure. Subsequently, wavelet transformation is performed to obtain the total effective energy input and the effective energy input rate corresponding to the mode combination frequency to further judge the critical angle of seismic incidence by comparing these two performance indexes under different seismic incidence angles. To validate this approach, finite element history analysis (FEHA) is imposed on both FE models to generate comparative data, and good agreement is found. The results demonstrate that the wavelet energy method can forecast the critical angle of seismic incidence of a transmission tower-line system with adequate accuracy, avoiding time-consuming and cumbersome computer analysis. The proposed approach can be used in future seismic design of transmission tower-line systems.

• Earthquakes and Structures
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• v.26 no.2
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• pp.149-162
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• 2024

Aiming at the current research on the dynamic response analysis of the vehicle-bridge system under earthquake, which fails to comprehensively consider the impact of seismic wave incidence angles, terrain effects and soil-structure dynamic interaction on the bridge structure, this paper proposes a multi-point excitation input method that can consider the oblique incidence seismic P Waves based on the viscous-spring artificial boundary theory, and verifies the accuracy and feasibility of the input method. An overall numerical model of vehicle-bridge-soil foundation system in valley terrain during oblique incidence of seismic P-wave is established, and the effects of seismic wave incidence characteristics, terrain effects, soil-structure dynamic interactions, and vehicle speeds on the dynamic response of the bridge are analyzed. The research results indicate that with an increase in P wave incident angle, the vertical dynamic response of the bridge structure decreased while the horizontal dynamic response increased significantly. Traditional design methods which neglect multi-point excitation would lead to an unsafe structure. The dynamic response of the bridge structure significantly increases at the ridge while weakening at the valley. The dynamic response of bridge structures under earthquake action does not always increase with increasing train speed, but reaches a maximum value at a certain speed. Ignoring soil-structure dynamic interaction would reduce the vertical dynamic response of the bridge piers. The research results can provide a theoretical basis for the seismic design of vehicle-bridge systems in complex mountainous terrain under earthquake excitation.

• Journal of Korean Physical Therapy Science
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• v.6 no.1
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• pp.931-942
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• 1999

The aim of this research is to grasp the relation between lumbago incidence rate and research hypothesis in the effects of sex life of the middle-aged couples in Taejon area upon lumbago. And so, this writer had questionaired the 400 middle-aged couples in five gus, Taejon megalopolis -Jung-gu, Seo-gu, Dong-gu, Yuseong-gu, and Taedeok-gu - from April 21, 1998 to May 10, 1998. Of them, total 209 question papers were drawn back; male 102, female 107. Analysis of the data is as follows. 1. 145(69.37%) subjects of total 209 had experience in lumbago after their sexual lives. 2. In the number of sex life a week, one or two times of lumbago incidence rate were the most rate as 41.55% and each other had a statistically significant relation (P 0.01). 3. In age and lumbago incidence rate, their thirties was 37.75% and each other had a significant relation (P 0.05). 4. In weight and lumbago incidence rate, the level of $50kg{\sim}60kg$ was highest and each other didn't have a significant relation (P 0.05). 5. In the mean time of sexual life, the period of $11{\sim}20$ minutes was 29.47% and each other had a significant relation (P 0.01). 6. In week time zone of sexual life and lumbago incidence rate, midnight was the highest rate, 36.23% and each other didn't have a significant relation (P 0.05). 7. In the lumbago incidence rate according to bedroom structure of sexual life, a bed was 38.17% and each other had a significant relation (P 0.05). 8. In the lumbago incidence rate according to sexual posture, a normal position showed the highest rate, 46.12% and each other didn't have a significant relation (P 0.05). Putting the abovesaid results together, lumbago has relation to the number of sex life a week, age, the mean time of sexual life, and bedroom structure of sexual life. Therefore, it is thought that it is necessary that middle-aged couples periodically study the educational programs to make an education for lumbago prevention, etc. the key points.

• The Journal of the Korea Contents Association
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• v.22 no.7
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• pp.187-201
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• 2022

This study analyzed the dynamic changes in the energy poverty structure of all households, elderly households, and single-person households in Korea. To this end, a TIP curve was derived and the focus was on changes in energy poverty intensity and poverty incidence. For the data, annual and quarterly data on fuel costs from the National Statistical Office's Household Income and Expenditure Survey were used. And the results were presented using data from the first quarter, where the energy poverty problem can be prominent due to the high proportion of heating costs among the four quarters. As a result of the analysis, there was no clear improvement in poverty intensity and poverty incidence over time in the analysis of all households. However, the analysis of elderly and single-person households showed improvement in poverty intensity and poverty incidence over time. In particular, in the results of the analysis using the data for the first quarter, the poverty intensity and poverty incidence of elderly and single-person households improved remarkably. In addition, the poverty intensity and poverty incidence of the elderly and single-person households were larger than the all households, and the energy poverty of single-person households was more severe than that of the elderly households.

• Journal of Korean Neurosurgical Society
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• v.59 no.2
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• pp.149-153
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• 2016

Objective : The aim of the present study is to estimate the incidence trend of head injury and the mortality based on traffic accident statistics and to investigate the impacts of rapid industrialization and economic growth on epidemiology of head injury in Korea over the period 1970-2012 including both pre-industrialized and post-industrialized stages. Methods : We collected data of head injury estimated from traffic accident statistics and seven hospital based reports to see incidence trends between 1970 and 2012. We also investigated the population structure and Gross National Income (GNI) per capita of Korea over the same period. The age specific data were investigated from 1992 to 2012. Results : The incidence of head injury gradually rose in the 1970s and the 1980s but stabilized until the 1990s with transient rise and then started to decline slowly in the 2000s. The mortality grew until 1991 but gradually declined ever since. However, the old age groups showed rather slight increase in both rates. The degree of decrease in the mortality has been more rapid than the incidence on head injury. Conclusion : In Korea during the low income stage, rapid industrialization cause considerable increase in the mortality and the incidence of head injury. During the high income stage, the incidence of head injury gradually declined and the mortality dropped more rapidly than the incidence due to preventive measures and satisfactory medical care. Nevertheless, the old age groups revealed rather slight increase in both rates owing to the large population structure and the declining birth rate.