• Title/Summary/Keyword: Falling rate

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Biological Nutrient Removal using Porous Media (다공성 담체를 이용한 생물학적 영양물질 제거)

  • Cho, Chang-Sik;Lee, Sang-Houck
    • Journal of Digital Convergence
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    • v.11 no.5
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    • pp.237-243
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    • 2013
  • This study aims to examine the modified $A^2/O$ process is useful to reduce the environmental pollution caused by nutrient in wastewater. Specific results are as follows: The removal rate was evaluated at each time period, ie., 18h, 8h, 6h, and 3h after the reaction started. The anoxic rate was more than 94-97% from 18h to 6h but was less than 50% before 6h. Thus, the test of nitrification was done using 6h as the optimal anoxic retention time and the aerobic retention time set at 24h. When the flow change was 1:1, the average ammonia concentration inputted was $30mg/{\ell}$. Returned top nitric acid solution and the concentration of ammonia solution falling into the anoxic reactor was about 50% of the initial concentration, and the flow change was 1:2, the concentration of ammonia falling into the anoxic reactor was about 62% of that of influxed ammonia. And the results of this study showed that the nitrogen removal rate can be improved by inputting untreated nitric acid and changing the flow of top nitrate solution using the modified $A^2/O$ method.

The time and duration of flowering in an Adonis multiflora (Ranunculaceae) population

  • Min, Byeong-Mee
    • Journal of Ecology and Environment
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    • v.37 no.4
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    • pp.155-163
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    • 2014
  • Adonis multiflora is a spring ephemeral herb growing in temperate deciduous forests. To determine the flowering properties of a natural population of A. multiflora, air temperature, flowering time, and flower-falling were monitored from February 2009 to May 2011. The A. multiflora population in this study started flowering in early March and ended it in mid-April. The average flowering duration of a flower was 14.4 days in 2009 and 19.6 days in 2011. The average duration of flower-falling was between 3.4 days and 4.2 days for three years. Cumulative flowering rate (CFR) was correlated with year day (YD), year day index (YDI), and Nuttonson's index (Tn), with correlation coefficients (CC) of over 0.9 at the 1% significance level; CC value between CFR and YD was the largest and that between CFR and YDI was the smallest. However, at the 5% significance level, CFR was closely related with Tn more than any other factors. The CCs between flowering times of two years in each plant were high and significant at 1% level. The YD value of flowering time of a flower was inversely related to its flowering duration significantly for three years. In a given plant, when more flowering started early, the flowering duration was longer. The first flower blossomed on 73.4 YD in 2010 and 78.9 YD in 2011, and remained for 16.7 days in 2009 and 27.4 days in 2011, respectively; the fifth flower developed on 92.5 YD in 2010 and 96.6 YD in 2011, and remained for 8.0 days in 2009 and 14.6 days in 2011. The YD differences between the flowering times of two flowers decreased in the order of inflorescence.

The Status of Accidents and Management for Electronic Assistive Devices among the Handicapped (장애인 전동보조기구 사고 및 관리현황에 관한 연구)

  • Kim, Deok-Ju;Lee, Hye-Jin;Yang, Yeong-Ae
    • The Korean Journal of Health Service Management
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    • v.10 no.3
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    • pp.223-234
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    • 2016
  • Objectives : The purpose of this study was to investigate accident cases involving electronic assistive devices, to determine how these accidents can be avoided and to devise preventative instructions for the handicapped who use these devices. Methods : This study was carried out from July 20 to October 3, 2015. A consent-based survey was conducted via mail and mobile phones targeting 700 electronic assistive device users, of which questionnaires from 290 users were collected and used in the analysis. Results : Accidents involving electronic assistive devices were investigated, especially the causes of the accidents and accident prevention education, as well as the status of the electronic assistive devices. The most common accident types were collision and falling, and it was found that the victims of the accidents usually suffered severe injury to their lower limbs. Most users used electronic assistive devices every day but rarely wore a safety belt because of discomfort. There were more incidents of collision and falling for older aged handicapped users, and the injury rate to the lower limbs was highest in handicapped elderly aged 50 years or older. Conclusions : In order to prevent accidents with electronic assistive devices in the future, a or management organizations must prepare specific safety guidelines and manage these accidents.

Evaluation of Layer Moduli of 4 Layered Flexible Pavement Structures Using FWD (FWD에 의한 4층 아스팔트 포장 구조체의 층별 탄성계수 추정)

  • Kim, Soo Il;Yoo, Ji Hyeung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.10 no.2
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    • pp.67-78
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    • 1990
  • An inverse self-iterative procedure is developed to determine layer moduli which are significant for the structural evaluation of pavements in developing rational and analytical rehabilitation technique. Falling weight deflectometer(FWD) is adopted as a non-destructive testing(NDT)device. The layer elastic theory is used to interpret NDT data. The theoretical deflection basins of pavement structures obtained by full factorial design are used for a parametric study on the characteristics of deflection basins and regression analyses. Regression equations to estimate layer moduli of flexible pavements are proposed through the regression analyses of theoretical deflection basins. The relationships between the rate of change of moduli and deflections are developed for the efficient iteration. An inverse self-iterative procedure to ensure the accuracy of the layer moduli is proposed. Validity and applicability of the developed procedure are verified through various numerical model tests.

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A Study on the Optimal Clothing Weight in an Air Conditioned Office in Summer (여름철 냉방실내의 적정착의량에 관한 연구)

  • Kim Sun Young;Lee Soon Won
    • Journal of the Korean Society of Clothing and Textiles
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    • v.9 no.3
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    • pp.45-51
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    • 1985
  • The purpose of this study is to research into the thermal condition and the weight of clothes suitable for the officers engagged in light works in an air-conditioned room in summer. The Major findings are as follows: 1. Thermal conditions of the working environment are $24.5^{\circ}C$ (Dry bulb temp.), $68\%$ (Relative humidity) and 2.6m/sec (Air Velocity). 2. Total clothing weights are 416.6 g/$m^2$ (male) and 340.9 g/$m^2$ (female). Underwear weights are 96.8g/$m^2$ (male) and 85.1g/$m^2$ (female). The latter turned out to be statistically significant in Sexual difference. 3. Means of the thermal sensation are 3.0 (comfortable; male) 2.7 ('Slightly cool' -'Comfortable'; female) and the relationship between clothing weights and thermal sensation proves to be significantly correlated in the case of female. 4. $66.7\%$ of the women and $37.1\%$ of the men feel sensation of coldness at the body's specific area and $79.5\%$ of the women and $54.3\%$ of the men reveals air-conditioning disturbance. 5. As the thermal sensation is close to 'cool-cold', sensation of coldness or air conditioning disturbance are showed up more frequently which is reversely related with weight of under-wear. It is also proved that air conditioning disturbances are influenced by sexual difference in addition to sensation of coldness and thermal sensation. 6. According to the result of experiment, we can have the idea that at condition $X_1$, the drop of limbs' skin temp. is remarkable. At condition $X_2$ skin temp. for distal limbs and mean skin temp. are raised and the falling degree is similar. At condition $X_3$, mean skin temp. and distal skin temp. are remarkably raised, and the falling degree decreases and the beats of pulse rate increase and diastoric blood pressure is lowered.

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A Study on Correlation of Entry into Hibernation and Epileptic Fit in Hibernators (동면돌입과 전간발작의 상호관련성에 관한 연구)

  • 오영근;이서울
    • Biomedical Science Letters
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    • v.5 no.2
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    • pp.167-179
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    • 1999
  • There are considerable interests in bat biology for investigating hibernation mechanism, in special regard to a hypothesis that the entry into hibernation is closely related with epileptic fit (petit mal) accompanying falling of body temperature, which is characterized by 3 spikes and wave/sec formation in electroencephalograph (EEG). This study was designed in order to examine physiological parameters (body temperature, heart rate, electroencephalograph and brain mapping) during normal patterns of the entry into hibernation and the hibernation period, and to observe effects of epileptogenic agents such as THC, Metrazol, and ILS on the physiological parameters. Based on the experimental results the entry into some hibernation seems to be related with epileptic fit, and therefore it is deduced that north temperate bats and the hamsters might be induced into hibernation by epileptogenic factors (pentylenetetrazol, THC and ILS etc) accompanying falling of body temperature and unique EEG and brain mapping.

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Risk Situation Detection Safety Helmet using Multiple Sensors (다중 센서를 이용한 위험 상황 감지 안전모)

  • Woo-Yong, Choi;Hyo-Sang, Kim;Dong-Hyeon, Ko;Jang-Hoon, Lee;Seung-Dae, Lee
    • The Journal of the Korea institute of electronic communication sciences
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    • v.17 no.6
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    • pp.1226-1274
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    • 2022
  • In this paper, we dealt with a safety helmet for detecting dangerous situations that focuses on falling accidents and gas leaks, which are the main causes of industrial accidents. the fall situation range was set through gravity acceleration measurement using an acceleration sensor, and as a result, a fall detection rate of 80% could be confirmed. .In addition, the dangerous gas concentration was measured through a gas sensor, and when a digital value of 188 or more was output through a serial monitor, it was determined as a gas dangerous situation, and a fall warning message and a gas warning message could be checked through a smart-phone application produced based on the app inventor program.

Mortality Characteristic and Prediction of Nasopharyngeal Carcinoma in China from 1991 to 2013

  • Xu, Zhen-Xi;Lin, Zhi-Xiong;Fang, Jia-Ying;Wu, Ku-Sheng;Du, Pei-Ling;Zeng, Yang;Tang, Wen-Rui;Xu, Xiao-Ling;Lin, Kun
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.15
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    • pp.6729-6734
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    • 2015
  • Background: To analyze the mortality distribution of nasopharyngeal carcinoma in China from 1991 to 2013, to predict the mortality in the ensuing five years, and to provide evidence for prevention and treatment of nasopharyngeal carcinoma. Materials and Methods: Mortality data for Nasopharyngeal Carcinoma in China from 1991 to 2013 were used to describe its epidemiological characteristics, such as the change of the standardized mortality rate, sex and age differences, urban-rural differences. Trend-surface analysis was used to study the geographical distribution of the mortality. Curve estimation, time series, gray modeling, and joinpoint regression were used to predict the mortality for the ensuing five years in the future. Results: In China, the standardized mortality rate of Nasopharyngeal Carcinoma increased with time from 1996, reaching the peak values of $1.45/10^5$ at the year of 2002, and decreased gradually afterwards. With males being 1.51 times higher than females, and the city had a higher rate than the rural during the past two decades. The mortality rate increased from age 40. Geographical analysis showed the mortality rate increased from middle to southern China. Conclusions: The standardized mortality rate of Nasopharyngeal Carcinoma is falling. The regional disease control for Nasopharyngeal Carcinoma should be focused on Guangdong province of China, and the key targets for prevention and treatment are rural men, especially after the age of 40. The mortality of Nasopharyngeal Carcinoma will decrease in the next five years.

Forecasting Construction Economy Through a Regression Analysis between Annual Interest Rate and Contract Amount (금리와 건설수주간 회귀분석을 통한 건설경제 예측기법)

  • Yi, Kyoo-Jin
    • Journal of the Korea Institute of Building Construction
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    • v.10 no.5
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    • pp.31-36
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    • 2010
  • Rising interest rates positively affect investment in construction, while falling interest rates affect it negatively. In other words, the interest rate is one of the most critical factors affecting the construction sector. The purpose of this research is to analyze the relationship between the annual interest rate and construction contracts, and to present a model for quantitatively forecasting the economic performance of the construction sector. Based on the statistical data of interest rate changes for 19 years (from 1991 to 2009), this research induces an equation through regression analysis that incorporates interest rate and construction contract amounts as independent and dependent variables, respectively. The result of the analysis shows that, in the building and private sector, the interest rates are closely related to, with a correlation coefficient as high as 0.85. It was also indicated that the contract amounts of private and building sectors may increase quite rapidly in 2012.

Korea and Japan Comparison Study of Distribution Industry: Focus on Input-out Analysis (유통산업의 한일비교 연구 - 산업연관분석을 중심으로 -)

  • Jho, Kwang-Hyun
    • Journal of Distribution Research
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    • v.16 no.5
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    • pp.171-192
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    • 2011
  • This paper focuses on the retail industry of industrial share of the GDP, productivity of distribution industry and input-out analysis between Korea and Japan, also results are summarized as follows. First, the share of GDP in agriculture, forestry and fisheries of the both countries is falling. That of manufacture increases in South Korea, while Japan is falling. While distribution industry shows vice versa. Employed population by industry is falling both countries also. The relative labor productivity shows that agriculture, forestry and fisheries, retail industry needs more labor, while manufacture has been met for both countries. Second, compare to Japan, the retail industry of Korea has been increased since 1990. Likewise, overall productivity of distribution industry in Korea has been increased while almost that of Japan has declined. Third, production inducement effects of Japan are greater than that of Korea. On the other hand, import inducement effects show vice versa. Fourth, as shown from the final demand of distribution industry and the rate of dependence on production inducement, we can see that the “increase in stocks” increases while gross government fixed capital formation shows vice versa. Korea's private consumption expenditure increases while Japan shows versa. South Korea's government consumption expenditure and exports are rising, on the other hand, that of Japan is declining. Fifth, the rate of dependence on distribution industry and import inducement shows the same tendency from both countries. As we can see from the private consumption expenditure, government consumption expenditure, gross government fixed capital formation, gross private fixed capital formation, increase in stocks, the rate of dependence on import inducement is more effective than the rate of dependence on production inducement. While the exports are comparatively ineffective. Sixth, the degrees of influence of retail industry are similar between Korea and Japan, while sensitivity of the Korean industry has been weakened. In this sense, strong policies are needed to boost the industry. Seventh, the investments in the retail industry of Korea showed the public-led trend, while Japan showed private sector-led investment trend. The investment trend of Korea's retail industry will be switched into private sector-led investment step by step in the future. This finding will be an important clue to set the policy direction of Korea distribution industry. Finally, both Korea and Japan are still in need of employment in retail industry. Not addressed in this paper, such as value-added-induced effects, employment inducement effect, will be remaining challenges in the following paper.

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