• Title/Summary/Keyword: Design comparison

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Development of Runoff Hydrograph Model for the Derivation of Optimal Design Flood of Agricultural Hydraulic Structures(1) (농업수리구조물의 적정설계홍수량 유도를 위한 유출수문곡선모형의 개발(I))

  • 이순혁;박명근;맹승진
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.37 no.3_4
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    • pp.34-47
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    • 1995
  • It is experienced fact as a regular annual event that the structure to he designed on unreasonable flood for the agricultural structures including reservoirs have been brought not only loss of lives, but also enormous property damage. For the solution of this problem at issue, this study was conducted to develop an optimal runoff hydrograph model by comparison of the peak flows and time to peak between observed and simulated flows derived by linear time-invariant and linear time-variant models under the condition of having a short duration of heavy rainfall with uniform rainfall intensity at nine small watersheds which are within the range of 55.9 to 140.7 square kilometers in area in Han, Geum, Nagdong and Yeongsan Rivers. The results obtained through this study can be summarized as follows. 1. Storage constants and Gamma function arguments were calculated within the range of 1.2 to 6.42 and of 1.28 to 8.05 respectively by the moment method as the parameters for the analysis of runoff hydrograph based on linear time-invariant model. 2. Parameters for both linear time-invariant and linear time-variant models were calibrated with nine gaged watershed data, using a trial and error method. The resulting parameters including Gamma function argument, N and storage constant, K for linear time-invariant model were related statistically to watershed characteristic variables such as area, slope, length of main stream and the centroid length of the basin. 3. Average relative errors of the simulated peak discharge of calibrated runoff hydrographs by using linear time-variant and linear time-invariant models were shown to be 0.75 and 5.42 percent respectively to the peak of observed runoff hydrographs. Correlation coefficients for the statistical analysis in the same condition were shown to be 0.999 and 0.978 with a high significance respectively. Therefore, it can be concluded that the accuracy of a linear time-variant model is approaching more closely to the observed runoff hydrograph than that of a linear time-invariant model in the applied watersheds. 4. Average relative errors of the time to peak of calibrated runoff hydrographs by using linear time-variant and linear time-invariant models were shown to be 16.44 and 19.89 percent respectively to the time to peak of observed runoff hydrographs. Correlation coefficients in the same condition were also shown to be 0.999 and 0.886 with a high significance respectively. 5. It can be seen that the shape of simulated hydrograph based on a linear time- variant model is getting closer to the observed runoff hydrograph than that of a linear time-invariant model in the applied watersheds. 6. Two different models were verified with different rainfall-runoff events from data for the calibration by relative error and correlation analysis. Consequently, it can be generally concluded that verification results for the peak discharge and time to peak of simulated runoff hydrographs were in good agreement with those of calibrated runoff hydrographs.

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A Study on CSV of Social Economy and Consumer Perspective (사회적경제와 소비자 관점의 공유가치창출(CSV) 연구)

  • Lee, Young-Il;Kim, Young-Shin
    • Journal of Distribution Science
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    • v.13 no.12
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    • pp.53-63
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    • 2015
  • Purpose - Recently, creating shared value (CSV) has attracted attention through plan sustainability and the growth of corporate management. Porter and Kramer (2011) defined the core concept of CSV as social value, economic profits, improvements in the economic social condition, and reinforcing competitiveness. The purpose of CSV, which is to pursue economic profits through a social solution to the problem, agrees with managing the objective of a social enterprise that prioritizes the pursuit of profits through the realization of a social purpose. Today, CSV studies focus on CSR and sustainability and reinforce competitiveness. However, few studies focused on the social economy. Precedent studies examined CSV using a company example, and few studies exist from the perspective of consumers and the point of view of a market society. Research design, data, and methodology - Therefore, this study examines CSV in comparison to a background of the social economy. This study also investigates and analyzes the concept of social value from the point of view of consumers, social problems, consumption value, corporate value, and the influence of consumers. This article develops three hypotheses. Hypothesis 1 investigates the correlation with social innovation that consumers thought as being necessary for social innovation by a company. Hypothesis 2 is used to confirm the influence of consumers in CSV. Therefore, this article investigates the influence of consumers on consumption action for companies that are indifferent to social problems. Hypothesis 3 is used to verify the correlation between the value that consumers demand through consumption and the corporate value that companies pursue other than profits. The three hypotheses were adopted and met the standard for suitability. Results - The importance of the CSV study from the consumer perspective was confirmed using the influence of consumers on CSV. Because the objective of company activities is either the consumer or the market, the influence that extends to interactions between the company and consumers to ensure the success of a business is significant. Regarding the CSV study, because it was an initial study, various approaches are subsequently developed. However, conceptual and practical case studies on CSV currently exist that may be used to verify the factors that comprise CSV. Therefore, the company example may enable verification of the factors that influence the composition of CSV through identification from the consumer perspective. In addition, studying CSV as an action result (of consumer satisfaction, of a company's profits and competitiveness, and of society's cancellation of a social problem) may enable the realization of a practice paradigm as opposed to simply thought and faith. Conclusions - First, this study confirms the social value of a business through the feasible and common pursuit of consumers by corporations. Second, customer influence accounts for an important part of CSV. Third, shared value commonly provides a necessary advantage to consumers, corporates, and society, and contributes to the economy and healthy social development. Fourth, corporates can conduct a business, generate profits, and realize value through improvements in social problems and by addressing their competitive strengths and weaknesses.

Influence of Authenticity on Electrical Energy Saving Behavioral Intention (진정성이 전기에너지 절약 행동의도에 미치는 영향)

  • Kim, Young-Doo
    • The Journal of Industrial Distribution & Business
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    • v.9 no.11
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    • pp.67-76
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    • 2018
  • Purpose - Electrical energy saving is one of the practical virtues relating to sustainable living. Therefore, policy-makers has tried to find a way to change the behaviors of individuals to encourage them to actively practice electrical energy saving, even if they have never had this concern or have only passively practiced electrical energy saving to this point. Prior research related to electrical energy saving can be categorized into several types. The first is focused on consumer characteristics linked to electrical energy saving. These studies are based on individual or household socio-demographic variables (e.g., age, gender, household income, education level, occupants, marital status, number of households), and psycho-graphics (e.g., environmental consciousness, value, attitude, motivation, lifestyle). The second is focused on policies (e.g., monetary incentives, information sharing, social comparison, feedback), and technologies (e.g., energy-efficiency home appliances, energy-reduced products, renewable resources). People generally have a favorable attitude towards electrical energy saving, while electrical energy saving practices tend to be less favorable. Therefore, it is necessary for policy-makers to seek out gaps between attitudes and behaviors and find alternatives to reduce these gaps. This study investigates the influence of authenticity on the behavioral intention of electrical energy saving. It is supposed that electrical energy saving practices are likely to be stronger as authenticity of individual or household becomes stronger. This study reviews prior literature and examines various studies to provide an understanding of the relationships between authenticity and electrical energy saving behavioral intention. Research design, data, and methodology - Hypothesis was drawn from analysis based on previous research. The items related to authenticity and electrical energy saving were selected from items found in previous research. To verify this hypothesis, data were collected via experimental survey method and the resulting data were analyzed using reliability analysis, correlation analysis, and hierarchical regression analysis. Results - This study found that authenticity had a positive impact on the behavioral intention of electrical energy saving. The higher the perceived degree of authenticity, the higher the behavioral intention of electrical energy saving. Conclusions - This study assesses the impact of authenticity on the behavioral intention of electrical energy saving. In order to enhance the practice of electrical energy saving, it is efficient strategy for policy-maker to improve the perceived authenticity of individuals.

A Comparison of the Social Perception of Hairdressers (헤어미용사에 대한 사회적 인식 비교)

  • Kim, Kwang-hee;Kim, Eun-Young;Kim, Jin-Sook
    • The Journal of the Convergence on Culture Technology
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    • v.6 no.2
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    • pp.177-182
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    • 2020
  • The purpose of this study is to compare the perceptions of hairdressers, hairdressers-to-be, and ordinary people on hairdressers. For this, 286 hairdressers, hairdressers-to-be, and ordinary people residing in Daegu and Gyeongbuk were surveyed and analyzed. The study results are as follows: First, the job preferred by hairdressers is running their own salon. Most of those involved in the beauty industry considered that anyone who has an aesthetic sense can become a hairdresser, the average education level is college, and 5-10 years of experience would be adequate. On the other hand, the majority of the ordinary people thought different. Second, most of the hairdressers thought that professional theoretical knowledge and skills are required for hairdressers and that they have the role of leading beauty. On the other hand, the majority of the hairdressers-to-be and ordinary people considered that what it takes to become hairdressers are design sense and creativity and that they should take the responsibility of cleanliness and service. Meanwhile, all the research subjects shared common ideas that the competence required for hairdressers is skills and female hairdressers are preferred. Third, the most common cause for hairdressers to move from a workplace to another was wage-related issues, and the most answered entry-level salary was between KRW 1 million and 1.5 million and average working hours a day 9-10 hours. Fourth, the research subject groups showed significant differences in their perception of the occupation of hairdresser. The results suggest that although the social perception of hairdressers is improving, ordinary people still need to change their perception.

Prevalence Study of Mothers' Perception on Pregnancy, Childbirth, and Childcare: Comparison Between Years 2002 and 2007 (영아기 첫 자녀를 둔 어머니의 임신 및 출산, 양육 변인에 관한 연구: 2002년과 2007년 실태 비교를 중심으로)

  • Kim, Yang Eun;Cho, Bok Hee;Jung, Min Ja
    • Korean Journal of Childcare and Education
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    • v.3 no.2
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    • pp.68-85
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    • 2007
  • The purpose of this study is to investigate the changes of mothers' condition including the level of knowledge and parenting stress that mothers have on infant development. The subjects of this study are 270 mothers whose infants range in age from birth to 36 months. The instruments used are: 1)KCDI(Knowledge of Child Development Inventory, Larsen & Juhasz, 1985) 2)Parenting Stress Scale(Kim & Kang, 1997), and a demographic questionnaire. The data analyses use SPSS 12.0 which employs basic statistics, reliability test, and t-test. This study is time-lag design covering five years. Therefore, the data collected originates from 2002 and 2007 to constitute input from two times. The results of this study indicate that the average pregnancy from the 2007 statistics occurred 0.46 months earlier, after marriage, as compared to pregnancies in 2002. Mothers who gave birth by natural birth increased from 59.9 % to 75.3 % over the five year period. Regarding knowledge of infant development, the level of mothers' knowledge was lower in 2007 than in 2002 according to study results. The level of parenting stress of mothers increased for the 2007 statistics as compared to the 2002 survey.

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A Study on Self-Esteem and Urinary Symptoms in Women with Urinary Incontinence (요실금환자의 골반근육운동에 따른 자아존중감과 배뇨증상에 관한 연구)

  • Lee Young-Hee;Kim Sun-Are
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.9 no.3
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    • pp.360-369
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    • 2002
  • Purpose: The purpose of this study was to help enhance the quality of life for women with urinary incontinence. Self-esteem, urinary symptoms, peak pressure and duration in seconds for vaginal contraction after pelvic muscles exercise were examined. Method: One-group pretest-posttest design was employed participants were 27 married women from G city. The instrument for this study were : the self-esteem scale developed by Rosenberg(1965). the Urinary Symptom Questionnaire, a subjective measurement of urinary incontinence, developed by Jackson et al.(1996) and the Perineometer used as an objective measurement of peak pressure and duration in seconds. Result: 1. Self-esteem showed significant improvement after the exercise (t=-3.832, p= .001). 2. Comparison of results before the pelvic muscles exercise and after showed that there was a statistically significant difference for several urinary symptoms including enuresis (t=2.833, p=.009), frequency of incontinence (t=2.964, p= .006), incontinence volume (t=2.280, p= .031), incontinence before getting to the restroom (t=3.035, p= .006), incontinence with no reason or feeling (t= 3.051, p= 005) burning sensation (t= 2.132, p=.043), and a sense of residual urine (t=2.267 p=.032). The mean scores showed improvement in the urinary symptoms of management of incontinence (M=$0.04{\pm}0.22$), daily frequency of incontinence management (M=$0.13{\pm}0.85$), urinary control (M=$0.15{\pm}0.86$), running to the restroom (M=$0.15{\pm}0.60$) incontinence caused by coughing or physical activities (M=$0.19{\pm}0.57$) and hesitancy (M=$0.07{\pm}0.55$). Overall urinary symptoms decreased significantly (t =3.073. p= .007). 3. Peak pressure showed an increase from a mean of $24.26{\pm}16.20mmHg$ before the exercise to a mean of $28.63{\pm} 17.79mmHg$ after (t=-2.399, p=.024). Duration in seconds also increased from a mean of $6.00{\pm}4.95sec$ to $9.15{\pm}5.83sec$ (t=-4.400, p= 000). Conclusion: These findings suggest that pelvic muscle exercise serves to decrease urinary problems, improve self-esteem and increase peak pressure and duration in seconds.

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Performance Comparison of Taylor Series Approximation and CORDIC Algorithm for an Open-Loop Polar Transmitter (Open-Loop Polar Transmitter에 적용 가능한 테일러 급수 근사식과 CORDIC 기법 성능 비교 및 평가)

  • Kim, Sun-Ho;Im, Sung-Bin
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.47 no.9
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    • pp.1-8
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    • 2010
  • A digital phase wrapping modulation (DPM) open-loop polar transmitter can be efficiently applied to a wideband orthogonal frequency division multiplexing (OFDM) communication system by converting in-phase and quadrature signals to envelope and phase signals and then employing the signal mapping process. This mapping process is very similar to quantization in a general communication system, and when taking into account the error that appears during mapping process, one can replace the coordinates rotation digital computer (CORDIC) algorithm in the coordinate conversion part with the Taylor series approximation method. In this paper, we investigate the application of the Taylor series approximation to the cartesian to polar coordinate conversion part of a DPM polar transmitter for wideband OFDM systems. The conventional approach relies on the CORDIC algorithm. To achieve efficient application, we perform computer simulation to measure mean square error (MSE) of the both approaches and find the minimum approximation order for the Taylor series approximation compatible to allowable error of the CORDIC algorithm in terms of hardware design. Furthermore, comparing the processing speeds of the both approaches in the implementation with FPGA reveals that the Taylor series approximation with lower order improves the processing speed in the coordinate conversion part.

Comparison of Absorption Rate Between Piroxicam-$\beta$-Cyclodextrin and Piroxicam in Korean Healthy Subjects After A Single Dose Administration (정상 성인 한국인에서 Piroxicam-$\beta$-cyclodextrin 정과 Piroxicam 확산정의 1회 투여시의 흡수속도 비교)

  • Jeon, Seong Sill;Cha, Hye Ri;Park, Yun Ju;Lee, Byung Chul;Kim, Nam Deuk
    • Korean Journal of Clinical Pharmacy
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    • v.8 no.2
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    • pp.95-100
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    • 1998
  • Piroxicam-$\beta$-cyclodextrin은 piroxicam을 $\beta$-cyclodextrin으로 포접시킨 비스테로이드성 항염증약물이다. 이러한 포접형 약물은 위장관에서의 흡수속도가 증가하는 것으로 외국자료에서 보고되고 있으며 이는 이 약물의 위장관 내성에 보다 나은 영향을 끼칠 수 있음을 시사하고 있다. 본 연구는 정상성인 한국인을 대상으로 randomized, crossover design에 의해 piroxicam-$\beta-cyclodextrin(Brexin^{(R)})$과 piroxicam 확산정$(Feldene^{(R)})$ 흡수속도를 비교하고자 하였다. 건강한 성인 8명의 피험자를 2군으로 나누어 시험약 또는 대조약을 각각 20 mg씩 20일의 휴약 기간을 두고 이중 맹검으로 교차 투여하였다. 시험약 또는 대조약의 투여 후 24시간 동안 일정 간격으로 채혈하여 HPLC 방법으로 혈장 내 piroxicam 농도를 측정하였다. $AUC_{0-24}\;({\mu}g/mL)$는 piroxicam-$\beta$-cyclodextrin군에서 $56.1\pm4.9$, piroxicam군에서 $57.3\pm5.6$으로 통계적인 유의성이 없었으나, 투여 후 0.5시간에서의 혈중농도는 piroxicam-$\beta$-cyclodextrin군 $2.9\pm0.4\;{\mu}g/mL$, piroxicam군 $1.6\pm0.3\;{\mu}g/mL$으로 통계적인 유의성을 보였다(p<0.05). 또한 최고혈중농도는 piroxicam-$\beta$-cyclodextrin$(4.3\pm0.5\;{\mu} g/mL)\;piroxicam(3.5\pm0.3\l{\mu}g/mL)$,으로 유의성이 있었으며(p<0.05), 흡수 속도상수는 piroxicam-$\beta$-cyclodextrin$(3.00\pm0.49\;h^{-1}), \;piroxicam(1.80\pm0.21\;h^{-1})$이었다(p<0.1). 이상의 결과에서, piroxicam-$\beta$-cyclodextrin정은 piroxicam 확산정과 비교하여 흡수되는 정도는 서로 비슷하지만 흡수 초기의 혈장농도 및 흡수속도상수에서 보다 빠른 약동학적 특성을 나타내었다.

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The Dynamic Basement Amplification Characteristics of a Dam Site using a Reference Site Method (기준관측소 방법을 이용한 댐체 기반암의 동적 지반증폭특성)

  • Wee, Soung-Hoon;Kim, Jun-Kyoung;Yoo, Seong-Hwa
    • Journal of the Korean earth science society
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    • v.38 no.2
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    • pp.161-171
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    • 2017
  • Observed ground motions are composed of three factors such as, seismic source, attenuation, and site amplification effect. Among them, the site amplification characteristics should be considered significantly when estimating seismic source and attenuation characteristics with more confidence. The site effect is also necessary when estimating not only seismic hazard in seismic design engineering but also rock mechanical properties. This study uses the method of H/V spectral ratio of observed ground motion between target site and reference site called a reference site method. In addition to using the vertical Fourier spectrum of the reference site, we try out the horizontal Fourier spectrum as a new method in this study. We analyze H/V spectral ratio of six ground motions respectively, observed at four sites close to Yedang Reservoir. We then compare site amplification effects at each site using 3 kinds of seismic energies including S waves, Coda waves energy, and background noise. The results suggest that each site showed similar site amplification patterns in S waves and Coda waves energy. However, the site amplification of background noise shows much different characteristics from those of S waves and Coda wave energy, which suggests that the background noises at each site have their own developing mechanism. Each station shows its own characteristics of specific resonance frequency and site amplification properties in low, high and specific resonance frequency ranges. Comparison of the method used in this study to the others that used different methods can provide us with more information about the dynamic amplification of a site characteristics and site classification.

Comparison of GMTI Performance Using DPCA for Various Clutters (DPCA를 이용한 지상 이동 표적 탐지에서 클러터 종류에 따른 성능 비교)

  • Lee, Myung-Jun;Lee, Seung-Jae;Kang, Byung-Soo;Ryu, Bo-Hyun;Lim, Byoung-Gyun;Oh, Tae-Bong;Kim, Kyung-Tae
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.28 no.6
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    • pp.487-496
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    • 2017
  • Ground moving target indicator(GMTI) using syntheticaperture radar(SAR) used for finding moving targets on wide background clutter in short time is one of good ways to monitor a traffic situation or an enemy's threat. Although displaced phase center antenna (DPCA) is a real time method with low computational complexity, there have been few studies about its performance against various ground clutters. Thus, we need to analyze GMTI performance for various ground clutters in order to design a suitable DPCA detector. In this paper, simulation results show that the conventional DPCA detector produces different performance in terms of detection rate and false alarm rate. In particular, the false alarm rate of heterogeneous or extremely heterogeneous clutter from urban area is higher than one of homogeneous clutter from natural area.