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Prediction on Mix Proportion Factor and Strength of Concrete Using Neural Network (신경망을 이용한 콘크리트 배합요소 및 압축강도 추정)

  • 김인수;이종헌;양동석;박선규
    • Journal of the Korea Concrete Institute
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    • v.14 no.4
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    • pp.457-466
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    • 2002
  • An artificial neural network was applied to predict compressive strength, slump value and mix proportion of a concrete. Standard mixed tables were trained and estimated, and the results were compared with those of the experiments. To consider variabilities of material properties, the standard mixed fables from two companies of Ready Mixed Concrete were used. And they were trained with the neural network. In this paper, standard back propagation network was used. The mix proportion factors such as water cement ratio, sand aggregate ratio, unit water, unit cement, unit weight of sand, unit weight of crushed sand, unit coarse aggregate and air entraining admixture were used. For the arrangement on the approval of prediction of mix proportion factor, the standard compressive strength of $180kgf/cm^2{\sim}300kgf/cm^2$, and target slump value of 8 cm, 15 cm were used. For the arrangement on the approval of prediction of compressive strength and slump value, the standard compressive strength of $210kgf/cm^2{\sim}240kgf/cm^2$, and target slump value of 12 cm and 15 cm wore used because these ranges are most frequently used. In results, in the prediction of mix proportion factor, for all of the water cement ratio, sand aggregate ratio, unit water, unit cement, unit weight of sand, unit weight of crushed sand, unit coarse aggregate, air entraining admixture, the predicted values and the values of standard mixed tables were almost the same within the target error of 0.10 and 0.05, regardless of two companies. And in the prediction of compressive strength and slump value, the predicted values were converged well to the values of standard mixed fables within the target error of 0.10, 0.05, 0.001. Finally artificial neural network is successfully applied to the prediction of concrete mixture and compressive strength.

Socio-Economic Differentials along the Ethnic Line among Coffee Farms in Central Highland, Vietnam (베트남 중부고원지대 커피농가의 사회경제적 격차: 민족성의 영향을 중심으로)

  • Chung, Su-Yeul;Lee, Sung-Cheol;Joh, Young Kug
    • Journal of the Economic Geographical Society of Korea
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    • v.19 no.2
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    • pp.360-377
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    • 2016
  • Since after the 1986 economic reform policy(Doi Moi), the central highland in Vietnam has transformed into one of the largest coffee producing areas. The transformation had been supported by mass migration of ethnic Kinhs from the coastal lowland. It did not take long for the Kinh migrants to be the ethnic majority in the region. Meanwhile the growth of coffee industry entailed in socio-economic disparity, specially between Kinh migrants and native ethnic minorities. The disparity has becomed obvious not only between coffee farming Kinhs and non-coffee farming ethnic minorities but also between coffee farming Kinhs and ehtnic minorities. The previous literatures highlight the lack of human and social capital and the lagging modernization in ethnic minority societies. However, they fall short in showing the explicit processes why ethnic minority coffee farmers earn less than ethnic majority counterparts. With a case study of Dak Lak province, this research attempts to show the reason why there is income gap between Kinh and ethnic minority Ede coffee farmers by comparing their ways of producing coffee and selling their products. The results show that Ede's land productivity is significantly lower than Kinh's. It is because Ede farmers use less fertilizer due to the shortage of the capital. Also they often get into debt for coffee production and should pay it back right after the harvest. It deprives them of chance to raise earning by selling the coffee beans at a higher price.

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Study of Dental Hygienist's Stress Degree and Adaptation Method (치과위생사의 스트레스 정도와 적응 방법에 관한 연구)

  • Gwon, Mi-Young;Jung, Mee-Hee
    • Journal of dental hygiene science
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    • v.4 no.3
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    • pp.133-140
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    • 2004
  • It examines closely the occupation characteristic primary factor which the dentistry hygienic company field which is working to presence at a sickbed is undergoing the degree and from the research which it sees and it grasps the adaptation method against it gropes bitterly with development of the dentistry hygienic company individual to join in, it contributed in dentistry medical treatment service quality improvement and the research which tries to sleep it attempted. Currently the dentistry hygiene which works from Seoul and the condition area subject matter dentist unit, the dentistry hospital and the general hospital dentistry back it did in the object which it will burn. 116 issues which become frequency in question 120 it used SPSS 10.0 and it analyzed. Result of this study is as following. (1) Was expose that stress degree by factor feels about commonness on the whole, and angle prospects and support connection stress at company were the biggest item by item, and appeared as on the other hand relation connection stress with patient is the smallest. (2) Stress that stress degree by each receives in case of there are a lot of other businesses to characteristic businesses except appeared highest. On the other hand, was expose that feel the lowest stress degree an item that other a type of occupation and discord are. (3) 'Do action of that throw goods or closes the door bump' appeared article highest by short term adaptation method about stress, and 'Think and gives up by fate' appeared highest by special skill adaptation method. Short term adaptation method appeared high than special skill adaptation method on the whole but the difference appeared as is very small. (4) Stress degree comparison by general special quality was shown difference that stress by only dental hygiene administration of justice selection motive keeps in mind. (5) All of the result that compare short term, long term adaptation method about stress that feel new dental higienist apple career dental higienist same difference be, but displayed high result in same munhang. (6) Was expose that difference that keep in mind from all arguments in comparison of short term adaptation method by general special quality does not exist, on the other hand, comparison of long-term adaptation method displayed result that religion among only variable keeps in mind statistically.

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Studies on Seed Production of Saddleback Clownfish, Amphiprion polymnus 1) Spawning, Egg Development and Larvae Culture (Saddleback clownfish, Amphiprion polymnus의 종묘생산에 관한 연구 1) 산란과 난 발생 및 자치어 사육)

  • Yoon, Young-Seock;Rho, Sum;Choi, Young-Ung;Kim, Jong-Su;Lee, Young-Don
    • Journal of Aquaculture
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    • v.18 no.2
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    • pp.107-114
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    • 2005
  • Clownfish are important and very popular fish in the ornamental aquarium industry. Demand for the fish is increasing dramatically. The present study was conducted to verify methods of broodstock management, patterns of spawning, rates of egg hatching and estimates of larval growth fur the saddleback clownfish, Amphiprion polymnus. Spawning occurred 8 times between August 2002 to June 2004 with 2 females and 1 male participating. Fertilized eggs were separated by an adhesive matrix and were oval in shape. The eggs were $2.46{\pm}0.13mm$ in size as measured along the longest axis. The percentage of fertilized eggs was 96.7%. Hatching was observed seven days post-spawning and hatching rate was 85.5%. The sizes of the newly-hatched larvae were $4.58{\pm}0.21mm$ TL (total length). Larvae had an open mouth and anus, and an oval yolk sac. At the 1 st day after hatching, the sizes of the larvae were $4.90{\pm}0.35mm$ TL. The larvae began to eat rotifers after complete yolk absorption. On the 5th day post-hatch, larvae were $5.88{\pm}0.31mm$ TL with complete fins and the survival rate was 48.6%. At 8 days after hatching, a band began to appear on head and back of the larvae indicating the beginning of metamorphosis. Metamorphosis was completed at an average TL of $15.00{\pm}2.12mm$ on the 23rd day after hatching. By the 45th day after hatching, juveniles averaged $22.76{\pm}3.22mm$ TL and survival rate was 28.4%.

A Study on the Characteristics of Vegetation Landscape of Fortress of Jeonju District in Represented on the (<전주지도>에 표현된 조선 후기 전주부성의 식생경관상)

  • Kang, In-ae;Rho, Jae-hyun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.36 no.2
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    • pp.1-10
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    • 2018
  • This study aims to find out the characteristics of the vegetation landscape characteristics and system which led the formation of the urban image in Jeonju in the late Joseon period connected with urban spatial structure, using designated as treasure No. 1586 which was made in the middle of 18C. The vegetation landscape characteristics of Jeonju in the late Joseon Dynasty derived from the analysis of are summarized as follows. Firstly, the vegetation landscape system in Jeonju is composed of the natural vegetation around mountain area of Jeonju-Buseong, the independent vegetation or cluster planting forests linked with the main facilities, the Bibo-Forests connected with topographical characteristics of Jeonju, and the vegetation combined with a private garden. Secondly, planting landscape was specialized using flag species and local species. Thirdly, the garden-type plantation centered on the back yard or front of main facilities, with the background of natural vegetation landscape combined with the mountain area and the vegetation combined with a private garden, dominates vegetation landscape of Jeonju Buseong as objects. Fourthly, in order to overcome the defects of topographical characteristics, the Bibo-Forests were emphasized as an important planting landscape element in addition to the vegetation landscape elements connected with main facilities. Fifth, ecological vegetation landscape technique was taken considering the topographical characteristics. The characteristics of vegetation landscape of Jeonju Buseong, which is derived from , have an important meaning to restore and reproduce Jeonju's historical features. Especially, the vegetation communities of the non-booming concept combined with the geographical features, the ecological landscape harmonizing with the topography, the round house type landscape mixed with the private house, and the specialization of vegetation landscape using local species are important factors in securing the city image based on the historical characteristics and creating a city brand that utilizes vegetation landscape.

A Study on the Changes of Landscape Perception for 'Bejing-Palgyeong(北京八景)' in China (중국 역대 북경팔경(北京八景)의 경관인식 변화에 대한 고찰)

  • Kwon, Ji-Young;Kim, Sung-Kyun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.38 no.2
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    • pp.1-13
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    • 2020
  • This study closely analyzed poems and paintings related to Beijing-Palgyeong, as well as ancient maps and ancient writings. Through the study, people who read this study can consider, Beijing-Palgyeong's the process of changing times, changing landscape perception, physical and symbolic landscape elements, structural analysis, national management relationships, and finally how it was localized as symbolic place. The view point of the Beijing-Palgyeong is distributed in four places, one outside and one inside the city. Outside of the capital city of Beijing-Palgyeong were concentrated in Seosan(西山) where the resting place of the emperor and the center of the landscape view of Beijing. The view point of Beijing-Palgyeong inside the capital city is located in two places in the royal palace's Imperial Garden and in two villages around the fortress. In other words, Beijing-Palgyeong was selected as a place closely related to the imperial family, emperor, and royal palace from the time of its initial creation. Since then, many scholars, including the emperor, have used it for national management through Won(元), Ming and Qing Dynasty, and it have become more and more characteristic of 'The capital city of eight scenic views'. The two places inside the capital city praised the Gods and Emperors in the same way. Outside the capital city, the two sites depict the comfortable lives of the people who are governed by the emperor and depicting the village landscape around the city. In the end, it can be seen that most of the Beijing-Palgyeong are related to imperial palaces and emperors. If you look at the physical landscape of Beijing-Palgyeong by element, it mainly contains the contents of national management and the emperor's eulogy. Qianlong Emperor established the Beijing-Palgyeong in 1751 through the construction of a monument. A four-character on the front of the monument, and inscribed with a seven-word written by the person on the back. It can be said that Qianlong Emperor's Beijing-Palgyeong were intended to show off the results of Manchurian rule through the material symbol of the monument. Beijing-Palgyeong have been transformed into a landmark, and modern people use it as an indicator of the Beijing-Palgyeong.

Effect of Rainwater Sprinkling System Utilization for Reducing Heat Stress in Milking Cows during Intense Heat Time (폭염시 착유우 고온스트레스 경감을 위한 빗물관수시스템 이용 효과)

  • Choi, Dong-Yoon;Cho, Sung-Back;Park, Kyu-Hyun;Yang, Seong-Hak;Hwang, Ok-Hwa;Kwag, Jung-Hoon;Jeong, Kwang-Hwa;Song, Jun-Ik;Yoo, Yong-Hee;Ahn, Hee-Kwon
    • Journal of Animal Environmental Science
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    • v.18 no.sup
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    • pp.21-28
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    • 2012
  • Since the temperature during summer is higher than the temperature which is suitable for milking cows, high temperature stress have severely affected dairy farmers due to decreased milk production. This study was carried out to investigate the effect of rainwater sprinkling system for reducing heat stress in milking cows during intense heat time. Treatment conditions were divided into 2 types ; No rainwater sprinkling (T1) and Rainwater sprinkling (T2). Temperature in the milking cow shed, feed intake, milk yield, respiration rate and rectal temperature were measured to investigate the effect of hot environment on the physiological, productive responses in milkig cows. The results obtained are summarized as follows : The daily milk yields were 24.5 and 27.4 kg per head in T1 and T2 during experimental period. The respiration rate was significantly higher in T1 than those of T2. The rectal temperature in T1 ($40.6^{\circ}C$) was higher than those of T2 ($39.8^{\circ}C$). It was suggested that rainwater sprinkling system installed in the dairy cow shed was effective means to reduce heat stress of milking cow.

Morphometric Analysis of Distances between Sacral Hiatus and Conus Medullaris Using Magnetic Resonance Image in Korean Adult (자기공명영상을 이용한 한국 성인의 엉치뼈틈새와 척수원뿔 사이 거리 연구)

  • Park, Tai Soo;Hwang, Byeong-Wook;Park, Sang-Joon;Baek, Sun-Yong;Yoon, Sik
    • Anatomy & Biological Anthropology
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    • v.29 no.4
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    • pp.145-154
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    • 2016
  • The purpose of this study was to provide basic biometric data on Korean adults through magnetic resonance imaging (MRI)-based measurements of the distances between the apex of sacral hiatus (SH) and the termination of dural sac (DS), and between SH and conus medullaris (CM) because they are critical to the performance of epidural neuroplasty. A total of 200 patients(88 males and 112 females) with back pain, who had no spine fracture, significant spinal deformity, and spondyloisthesis were selected for this study. The subjects were of mean age 54.3 (20~84) years and mean height 161.3 cm (135~187). T2-weighted MRI images were used for correlation analysis to evaluate the relationships between the distances, and variables such as sex and height. In all patients, the mean distance between SH and DS was $62.8{\pm}9.4mm$ and the mean distance between SH and CM was $232.2{\pm}21.8mm$. The minimum distance and the maximum distance between SH and DS were 34.8 mm and 93.9 mm respectively, and the minimum distance and the maximum distance between SH and CM were 155.0 mm and 284.0 mm respectively. In female patients, both the distances between the SH and DS, and between SH and CM were shorter when compared to those of the male patients(p<0.05). Both the distances between SH and DS and between SH and CM showed a significant correlation with height(p<0.01). The results of this study will provide a useful biometric data on the distances between SH and DS and between SH and CM in Korean in ensuring clinical safety and in the development of more effective catheterization techniques for epidural neuroplasty in Korean.

A Comparison Study of Alkalinity and Total Carbon Measurements in $CO_2$-rich Water (탄산수의 알칼리도 및 총 탄소 측정방법 비교 연구)

  • Jo, Min-Ki;Chae, Gi-Tak;Koh, Dong-Chan;Yu, Yong-Jae;Choi, Byoung-Young
    • Journal of Soil and Groundwater Environment
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    • v.14 no.3
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    • pp.1-13
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    • 2009
  • Alkalinity and total carbon contents were measured by acid neutralizing titration (ANT), back titration (BT), gravitational weighing (GW), non-dispersive infrared-total carbon (NDIR-TC) methods for assessing precision and accuracy of alkalinity and total carbon concentration in $CO_2$-rich water. Artificial $CO_2$-rich water(ACW: pH 6.3, alkalinity 68.8 meq/L, $HCO_3^-$ 2,235 mg/L) was used for comparing the measurements. When alkalinity measured in 0 hr, percent errors of all measurement were 0~12% and coefficient of variation were less than 4%. As the result of post-hoc analysis after repeated measure analysis of variance (RM-AMOVA), the differences between the pair of methods were not significant (within confidence level of 95%), which indicates that the alkalinity measured by any method could be accurate and precise when it measured just in time of sampling. In addition, alkalinity measured by ANT and NDIR-TC were not change after 24 and 48 hours open to atmosphere, which can be explained by conservative nature of alkalinity although $CO_2$ degas from ACW. On the other hand, alkalinity measured by BT and GW increased after 24 and 48 hours open to atmosphere, which was caused by relatively high concentration of measured total carbon and increasing pH. The comparison between geochemical modeling of $CO_2$ degassing and observed data showed that pH of observed ACW was higher than calculated pH. This can be happen when degassed $CO_2$ does not come out from the solution and/or exist in solution as $CO_{2(g)}$ bubble. In that case, $CO_{2(g)}$ bubble doesn't affect the pH and alkalinity. Thus alkalinity measured by ANT and NDIR-TC could not detect the $CO_2$ bubble although measured alkalinity was similar to the calculated alkalinity. Moreover, total carbon measured by ANT and NDIR-TC could be underestimated. Consequently, it is necessary to compare the alkalinity and total carbon data from various kind of methods and interpret very carefully. This study provide technical information of measurement of dissolve $CO_2$ from $CO_2$-rich water which could be natural analogue of geologic sequestration of $CO_2$.

Feeding Effects of Whole Crop Rice based TMR on Growth Performance and Carcass Characteristics of Hanwoo Steers (사료용 벼 위주 TMR 급여가 거세 한우의 생장 능력 및 도체 특성에 미치는 영향)

  • Kim, Jong Geun;Zhao, Guoqiang;Liu, Chang;Nan, Wei Sheng;Kim, Hak Jin;Kim, Kyoung Hoon;Ahn, Eok Geun;Min, Hyung-Gyu
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.39 no.2
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    • pp.97-104
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    • 2019
  • This experiment was conducted to investigate the effect of whole crop rice (WCR) based TMR on growth performance and carcass characteristics of Hanwoo steers. WCR "Yeongwoo"was harvested at yellow ripen stage and ensiled for 60 days. The crude protein (CP), acid detergent fiber (ADF), neutral detergent fiber (NDF), in vitro dry matter digestibility (IVDMD) and total digestible nutrient (TDN) content was 8.4 %, 28.0 %, 53.8 %, 72.4 % and 66.8 %, respectively. For silage quality, pH was 4.37 and lactic and butyric acid content were 2.84 and 0.04 % in DM. Sixteen Hanwoo steers (8-mon-old) were allocated into either a control (commercial TMR) and WCR-TMR (WCR-based TMR) group. The TMR were fed according to the feeding stage phase: growing (Initiate~14 month), early fattening (15 month~21 month) and late fattening (22 month~30 month). The body weight of control group increased (P<0.05) until early fattening stage, but late growing stage of WCR-TMR group was higher than that of control (P<0.05). Average daily gain (ADG) was significantly greater (P<0.05) in WCR-TMR group (total 0.78 kg/head) compared to control (total 0.66 kg/head) except for late fattening stage. The marketing weight and carcass weight were higher in WCR-TMR group (726 vs 765 kg; 417.8 vs 450.4 kg). The back fat thickness (11.75 vs 13.00 mm), Longissimus dorsi area (88.00 vs $89.88cm^2$) and yield index (65.87 vs 64.30) were not different between the two groups (P>0.05) and also no difference in meat yield grade (A : B : C = 2 : 4 : 2). Marbling score (4.00 vs 4.13), meat color (4.75 vs 4.75), fat color (3.13 vs 2.88), texture (1.25 vs 1.50) and maturity (2.00 vs 2.00) were not significant difference between the two groups and meat quality grade ($1^{{+}{+}}:1^+:1:2:3=0:2:4:2:0$) was also not different. In conclusion, TMR feeding based on WCR silage showed superiority in carcass yield and ADG compared to control TMR. It is considered that the use of WCR for feed is a necessary option for the substitution of the imported forages and the government's policy for rice production adjustment.