• Computers and Concrete
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• 제25권6호
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• pp.525-535
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• 2020

The use of pile foundations has become more popular in recent years, as the combined action of the pile cap and the piles can increase the bearing capacity, reduce settlement, and the piles can be arranged so as to reduce differential deflection in the pile cap. Piles are relatively long, slender members that transmit foundation loads through soil strata of low bearing capacity to deeper soil or rock strata having a high bearing capacity. In this study analysis of pile cap with considering different parameters like depth of the pile cap, width and breadth of the pile cap, type of piles and different types of soil which affect the behaviour of pile cap foundation is carried out by using Finite Element Software ANSYS. For understanding the settlement behaviour of pile cap foundation, parametric studies have been carried out in four types of clay by varying pile cap dimensions with two types of piles namely normal and under-reamed piles for different group of piles. Furthermore, the analysis results of settlement and stress values for the pile cap with normal and under-reamed piles are compared. From the study it can be concluded that settlement values of pile cap with under-reamed pile are less than the settlements of pile cap with normal pile. It means that the ultimate load bearing capacity of pile cap with under-reamed piles are greater than the pile cap with normal piles.

• 한국초등과학교육학회지:초등과학교육
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• 제28권4호
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• pp.476-486
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• 2009

The purpose of this study was to investigate elementary gifted students' characteristics of observing and inferring in the inquiry activities. For this study, 40 students of the 4th and 5th grades participated in inquiry activities where the strata were developed well, Haenam Uhangri province. And we analyzed the outcomes of students' inquiry activities. The results are as follows. First, 119 units as observing results were obtained, but most of them showed that they were not focused on the portion of stratus, but that they were implicated in whole stratus as observing object. Second, 90 units were collected with reasoning results, but 4 units of them were wrong in constructing of inferring. Based on outcomes of students' inferring, elementary students preferred to apply deductive inferring method rather than use abductive inferring. Third, only 39 of 119 units acquired from observing were used for constructing inferring and 80 which were discovered from observing activities were discarded without applying of inquiry activities. Fourth, about 42% of students' inferring results were in accord with them of the geologists. But 58% views which didn't agree with geologists showed that they were applied to misconceptions among constructing inferring.

• 응용통계연구
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• 제22권6호
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• pp.1301-1313
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• 2009

미국 노동통계청에서 사용하고 있는 BLS 방법의 효율성과 민감성에 관한 연구 결과에 의하면 표본 틀 (Sample frame) 자료와 조사된 자료의 상관관계가 높을수록 BLS 무응답 보정 효과는 커지는 것으로 알려져 있다 (이석진과 신기일, 2008). 그러나 표본 틀 자료와 조사된 자료의 상관계수가 층별로 크기가 다른 경우, BLS 보정 효과는 달라질 수 있다. 따라서 일반적으로 실시되는 표본 설계에서는 층화추출 방법이 사용되기 때문에 각 층의 표본 크기와 상관계수가 다른 경우의 BLS 보정 효과률 살펴보는 것은 매우 중요하다. 본 논문에서는 층의 표본 크기와 상관계수 그리고 무응답 비율에 따른 BLS 무응답 보정 효과를 살펴보았다. 이를 위해 사용된 자료는 노동부의 월별 자료인 2007년 매월노동통계 자료이다.

• 한국지구과학회지
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• 제27권7호
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• pp.768-777
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• 2006

The goal of this study is to elucidate the fusulinid biostratigraphy of the Carboniferous limestones distributed in the Gangdong area of Samcheok coalfield, Korea. The Carboniferous strata of the study area mainly comprise alternaton of dark gray shale, dark gray and reddish sandstone, and gray limestone. The limestones consist mainly of wackestonepackstone containing various fossil fragments such as crinoid, coral, brachiopod, foraminifera, fusulinid, and bryozoa; this observation thus suggests that the study site was the shallow marine environments. A tital of 12 species belonging to 5 genera of fusulinids are identified from the limestones of the Gangdong geologic section: Ozawainella turgida Sheng, Ozawainella sp. A, Ozawainella magna Sheng, Pseudostaffella antiqua (Dutkevich), Pseudostaffella paracompressa Safonova, Pseudostaffella kimi Cheong, Pseudostaffella sp., Beedeina lanceolata (Lee and Chen), Beedeina samarica (Rauser-Chernoussova), Beedeina sp. A, Neostaffella sphaeroidea cuboides Rauser-Chernoussova, and Hanostaffella hanensis Cheong. Such fusulinids species were reported from the lower part of the Geumcheon Formation in Samcheok coalfield and the middle Moscovian stage in Eurasia. On the basis of the fusulinid biostratigraphic correlation of the Gangdong geologic sections (A) to (C), the limestone should be overlapped by faults and folds. Moreover the stratigraphic thickness of the limestone is thinner than the thickness of the limestone outcrop of the Gangdong geologic section. Therefore, the stratigraphic sequence of the Gangdong geologic section is represented as the Gangdong geologic section (A).

• Geomechanics and Engineering
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• 제20권6호
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• pp.517-525
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• 2020

The long-term stability of rock engineering is significantly affected by the time-dependent deformation behavior of rock, which is an important mechanical property of rock for engineering design. Although the hard rocks show small creep deformation, it cannot be ignored under high-stress condition during deep excavation. The inner mechanism of creep is complicated, therefore, it is necessary to investigate the relationship between microscopic creep mechanism and the macro creep behavior of rock. Microscopic numerical modeling of sandstone creep was performed in the investigation. A numerical sandstone sample was generated and Parallel Bond contact and Burger's contact model were assigned to the contacts between particles in DEM simulation. Sensitivity analysis of the microscopic creep parameters was conducted to explore how microscopic parameters affect the macroscopic creep deformation. The results show that the microscopic creep parameters have linear correlations with the corresponding macroscopic creep parameters, whereas the friction coefficient shows power function with peak strength and Young's modulus, respectively. Moreover, the microscopic parameters were calibrated. The creep modeling curve is in good agreement with the verification test result. Finally, the creep curves under one-step loading and multi-step loading were compared. This investigation can act as a helpful reference for modeling rock creep behavior from a microscopic mechanism perspective.

• Nutritional Sciences
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• 제7권4호
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• pp.218-222
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• 2004

Iron deficiency anemia (IDA) is the world's most common nutritional problem. It is characterized by a low hemoglobin (Hb) level and low iron status. A study was conducted to investigate the incidence of iron deficiency anemia in day scholar girls belonging to different socioeconomic strata at Punjab University, Lahore. Iron status of the subjects was estimated by measuring Hb, hematocrit (Hct), red blood cell (RBC) count, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCR), serum iron, serum ferritin, total protein and albumin. Results indicated that females belonging to low socioeconomic strata had lower values for Hb, Hct, RBC count, total protein and albumin. Serum iron, serum ferritin, MCV and MCH values fell within the normal range for all of the socioeconomic groups. However, serum iron and ferritin varied with socioeconomic status and higher-income groups had significantly higher serum iron and ferritin. It was concluded that anemia may develop due to poor intake and absorption of iron and that those in the low-income bracket are the most affected group.

• 대한지역사회영양학회지
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• 제2권4호
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• pp.633-646
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• 1997

Korea has not tried any food consumption survey so far except the national nutrition survey, which does not show food consumption patterns of different income stratas. The results of the family income and expenditure survey(FIES) by the national statistical office can be precious sources which show household food consumption patterns due to large, random. Samples, year-round survey period and socioeconomic background data. This study analyzed the FIES data to find out food consumption patterns including nutrient intakes and frequently consumed foods by households among different monthly income levels. Big difference was found in food consumption patterns among the quartile-income groups especially the amount of consumed foods, food expenditure, and nutrient intakes. For every food item, the higher the monthly invomr, yhr motr og goof yhry vondumrf. The monthly food expenditure of higher higher income strata was composed with higher percentage of relatively expensive foods compared to other stratas. Nutrient intake levels of lower income strata were 50-60% of the RDA, which showed the necessicity of food assistance programs for those high risk groups to complement the nutritional difficiency. (Korean J Community Nutrition 2(4) : 633-646, 1997)

• 한국농공학회논문집
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• 제47권6호
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• pp.47-57
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• 2005

Stress distribution in soils is the very important element to design and to solve the problems of settlement, safety of foundations and trafficability of constructing vehicle in civil engineering. This research presents the comparative estimation of the actual and theoretical measurement on the underground stress of outer layer for each soil after the observation of each top soil layer fur its vertical and horizontal stresses in (1) homogeneous sand ground (2) weak stratum with the sand soil (3) weak stratum with gravel of the soil model, and it also investigates the effect of subsidence of ground by the repeated load. The underground stresses fumed out to be different in the value of theoretical and actual measurement after the trial examination of model. This study has the purpose of suggesting the better construction method of running equipment on weak stratum by comparing the estimated value of trial experiment and theory on underground stress of the weak ground surface area and of raising up the necessity of the continuous research hereafter.

• 한국초등과학교육학회지:초등과학교육
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• 제33권3호
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• pp.510-523
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• 2014

Modern society is rapidly changing in the fields of science and technology, with new information and knowledge constantly being discovered. So enhancing the creativity and positive attitude of students is important. STEAM education enables students to develop their creativity, personality, intelligence and sensitivity with a well-balanced curriculum. In this study, considering the student's interest, a theme-centered STEAM program was developed in the 'Strata and Fossils' unit of elementary 4th grade science. The purposes were to find the impact on the academic achievement, creative problem solving abilities, and scientific attitude of elementary school students. The STEAM program are composed of contents which can be applied effectively indoors. As application results for STEAM program to J elementary school's students in J province, the experimental group increased significantly in the academic achievement, creative problem solving abilities and scientific attitude compared to the control group. Therefore, it is necessary to be developed continuous and systematic STEAM programs in units of various subjects to improve the students' academic achievement, creative problem solving abilities and scientific attitude.

• Journal of Plant Biology
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• 제17권2호
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• pp.87-94
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• 1974

This survey has been carried out on ten species(Erythronium japonicum, Symplocarpus renifolius, Adonis amurensis var. ramosa, Corydalis turtschaninovii var. genuina, Primula sieboldii forma spontanea, Anemone raddeana, Gagea Iutea, Heloniopsis japonjca, Hylomecon japonicum, and Convallaria majalis var. keiskei in the undergrowth of a forest of deciduous broad-leaved trees in the Kwangnung area of Kyung-Ki Province. They always bloom towards the end of March which is earlier than most of the other plants do. They completely finish up their matter productions before foliage of the deciduous trees, which are the upper strata plants, grows broader or to cite in other terms, before the relative light intensity in the lower strata is fallen to the lowest degree to become to insufficient to allow for photosynthesis. These phanerophytes naturally wither down between June and July. The above mentioned phenomenon clearly demonstrates a kind of the ecological niches and habitat segregation in terms of using sunlight to her greatest advantage. Soon after these herbs wither they make their own winter buds-life form-around their roots and then go into hibernation. The intensity of light in this forest zone was measured through the use of a lux meter in order to investigate it's seasonal variations. In additions, an intensive survey on the duration of their efflorescence was fullfilled.