• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.2
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• pp.81-91
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• 1998

Water level of irrigation reservoir during the flood season could be kept to a certain level, so called, flood control level by releasing the flood inflow in advance in order to reduce the peak discharge of next coming flood and the damage of inundation. Concept of restriction intensity of water supply was introduced to evaluate the influence of flood control volume on the irrigation water supply. Restriction intensity can be calculated by multiplying the ratio of restriction to the days of restriction which are obtained from the operation rule curve and daily water level of irrigation reservoir and it has the dimension of % day. The method of restriction intensity was applied to the Yedang irrigation reservoir with the observed data of 30 years to review whether the present flood control volume is reasonable or not, and suggest the optimal flood control volume, if possible.

• Journal of Fisheries and Marine Sciences Education
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• v.19 no.2
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• pp.310-322
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• 2007

This study is to find ways of support for beginning teacher induction in elementary school with constructing model of professional development. To achieve this purpose, this study reviewed significance of beginning teacher induction program, the bridge to life learning, and constructed the model of professional development for beginning. The final conclusion about ways of support as support intensity are orientation based on demanding of beginning teacher, bridge connection with veteran teacher, coordination of working conditions, collaboration among peer teacher, and strengthening computer network at week intensity level. At strong intensity level, the ways of support for beginning teacher are institutionalization on election and training of mentor, institutionalization on compulsory induction for 1 year, development and operation of teacher education center, and furtherance of school learning organization.

• Journal of Climate Change Research
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• v.6 no.2
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• pp.143-158
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• 2015

This study developed the emission intensity estimation method of GHGs by considering the characteristics of the models and time series. The telematics device was installed on the vehicle (OBD-II) to collect information on the operation conditions from each sample vehicle of public authorities. As a result of comparing the mileage distance and fuel consumption, the matching degree is analyzed very high, showed a ${\pm}1{\sim}4%$ error for each vehicle. By comparing driving record diary of vehicles managed by public authorities, this study presents the method that can be used to verify driving information in order to derive the GHGs emission intensity.

• ETRI Journal
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• v.40 no.6
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• pp.794-801
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• 2018

This paper proposes a novel graphene-based optical microelectromechanical systems MEMS accelerometer that is dependent on the intensity modulation and optical properties of graphene. The designed sensing system includes a multilayer graphene finger, a laser diode (LD) light source, a photodiode, and integrated optical waveguides. The proposed accelerometer provides several advantages, such as negligible cross-axis sensitivity, appropriate linearity behavior in the operation range, a relatively broad measurement range, and a significantly wider bandwidth when compared with other important contributions in the literature. Furthermore, the functional characteristics of the proposed device are designed analytically, and are then confirmed using numerical methods. Based on the simulation results, the functional characteristics are as follows: a mechanical sensitivity of 1,019 nm/g, an optical sensitivity of 145.7 %/g, a resonance frequency of 15,553 Hz, a bandwidth of 7 kHz, and a measurement range of ${\pm}10g$. Owing to the obtained functional characteristics, the proposed device is suitable for several applications in which high sensitivity and wide bandwidth are required simultaneously.

• Current Optics and Photonics
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• v.7 no.6
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• pp.708-713
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• 2023

A robust all-fiber nonlinear amplifying loop-mirror-based mode-locked femtosecond laser is demonstrated. Power-dependent nonlinear phase shift in a Sagnac loop enables stable and power-efficient mode-locking working as an artificial saturable absorber. The pump power is adjusted to achieve the lowest intensity noise for stable long-term operation. The minimum pump power for mode-locking is 180 mW, and the optimal pump power is 300 mW. The lowest integrated root-mean-square relative intensity noise of a free-running mode-locked laser is 0.009% [integration bandwidth: 1 Hz-10 MHz]. The long-term repetition-rate instability of a free-running mode-locked laser is 10^-7 over 1,000 s averaging time. The repetition-rate phase noise scaled at 10-GHz carrier is -122 dBc/Hz at 10 kHz Fourier frequency. The demonstrated method can be applied as a seed source in high-precision real-time mid-infrared molecular spectroscopy.

• Journal of Distribution Science
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• v.17 no.3
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• pp.97-105
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• 2019

Purpose - The purpose of this study is to investigate the effect of the government support project on traditional market and the interaction effect between the government support project and the competition intensity. Therefore, this study focuses on the competition intensity of individual stores in traditional markets, unlike the traditional research flow, which is beyond the competitive structure of traditional markets and large retailers. Research design, data, and methodology - This study is based on the data of 'Statistics of Traditional Market in 2017'. In this study, a multiple regression equation was constructed using the number of government support projects as an independent variable, competition intensity as an interaction, and sales per store, number of customers per store as a dependent variable for analysis. A multiple regression equation was constructed for the main effect analysis. To investigate the effect of the interaction, cohen(1980)'s regression equation and two-way ANOVA were used. Results - First, according to this study, the traditional market participated in the government support project showed that the sales and the number of visitors per store in the traditional market were higher than those in the non-participation market. Second, the impact of government support projects on sales per store(also number of visiting customers per store) can be different depending on the competition intensity. More specifically, if the market is politically supported by a market with a high level of competition, it may be more effective than the market with no support. Conclusions - Based on the results of the study, we suggested academic and practical implications and suggested that competition intensity of stores in the traditional market should be considered in the future. The implications of this study are as follows. First, the effects of the government's traditional market support project were analyzed empirically. Second, this study is different from the previous studies in that it examined the competitive strengths and the effects of individual stores in traditional markets, away from competition between traditional market and large retailers. Third, it provided practical implications for the operation of government support projects.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.2
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• pp.666-671
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• 2016

This paper introduces a device providing close local lighting to the affected part, where the operation-purpose astral lamp alone cannot shed light directly, in an operation room of hospitals or clinics, which helps clinical doctors perform safe treatment of the affected part deep inside a human body. This medical assisting lighting is a device necessary to prevent fatal operation failures, which can occur with minute operation processes, such as tumor removal or angiorrhaphy. The components, such as the light source and power supply were designed to be low power consuming and small in size, have a narrow angle lens was used to increase the light spreading effect and focused illumination. The end-caps of the light transmission device using an optical cable and the lighting device were designed in the waterproof type to enable disinfection of these devices after use for the next patients. According to the measurement of the light source properties made after development of the retractor lighting device, the illumination intensity was 490 lux, the brightness was $11,550cd/m^2$, general color rendering index was 78, color temperature was 11,000K, and the intensity distribution was even, which were confirmed to be adequate for medical assisting local lighting.

• Korean Journal of Optics and Photonics
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• v.6 no.3
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• pp.222-227
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• 1995

A single mode, 100-mW diode laser was injection-locked by the master laser which was spectrally narrowed with Littman-type grating feedback. In the incomplete-injection-locking, we observed that two frequencies were simultaneously generated from the slave laser. The power ratio and frequency shift of two frequency components were proportional to the square of injected laser intensity. When the ratio of the injection intensity to the slave laser intensity was about $10^{-3}$, the injection-locking bandwidth was to be about 1.4 GHz. The bandwidth proportionally increased to the square root of the injection intensity, which was in good agreement with the theoretical predictions. The Iinewidth of the locked-laser was about 2.5 MHz, which was five times as narrow as that of free-running operation. ation.

• The Journal of the Korea Contents Association
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• v.18 no.11
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• pp.643-654
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• 2018

In order to understand and manage traffic flows in urban areas in the past, a variety of traffic engineering theoretical indicators such as intersection lag and highway speed have been applied. However, these theories and indicators have been developed under the constraints of traffic engineering research before the construction of intelligent transportation system. Since the ATIS system currently exists, it is necessary to introduce a separate traffic engineering technology that utilizes the data. In this paper, it is aimed to confirm whether it is applicable to intermittent flow (approach road, intersection, control group, main road axis) by using 'congestion intensity' which is already used in traffic engineering field. The results of this study are as follows: (1) The traffic signal improvement effect of urban road access road, intersection road, control group, Two verification studies were performed to verify the derived congestion intensity index. (1) verification of congestion intensity threshold value analysis and (2) crossing improvement using the congestion intensity. Through verification, it was confirmed that it is possible to apply the congestion intensity in the inter - city intermittent flow using the 5 - minute unit speed data so as to be able to escape from the existing traffic signal operation management which is past passive and manpower limit.

• Proceedings of the Korean Reliability Society Conference
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• 2004.04a
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• pp.15-25
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• 2004

Inherent reliability depends on decisions made during design and manufacture. Reliability degrades with age and production rate (or usage level/intensity). System design based on some nominal production rate. Actual production rate can differ-depends on commercial considerations.(omitted)