• Title/Summary/Keyword: Mathematical process

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A Study of Organic Matter Fraction Method of the Wastewater by using Respirometry and Measurements of VFAs on the Filtered Wastewater and the Non-Filtered Wastewater (여과한 하수와 하수원액의 VFAs 측정과 미생물 호흡률 측정법을 이용한 하수의 유기물 분액 방법에 관한 연구)

  • Kang, Seong-wook;Cho, Wook-sang
    • Journal of the Korea Organic Resources Recycling Association
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    • v.17 no.1
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    • pp.58-72
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    • 2009
  • In this study, the organic matter and biomass was characterized by using respirometry based on ASM No.2d (Activated Sludge Model No.2d). The activated sludge models are based on the ASM No.2d model, published by the IAWQ(International Association on Water Quality) task group on mathematical modeling for design and operation of biological wastewater treatment processes. For this study, OUR(Oxygen Uptake Rate) measurements were made on filtered as well as non-filtered wastewater. Also, GC-FID and LC analysis were applied for the estimation of VFAs(Volatile Fatty Acids) COD(S_A) in slowly bio-degradable soluble substrates of the ASM No.2d. Therefore, this study was intended to clearly identify slowly bio-degradable dissolved materials(S_S) and particulate materials(X_I). In addition, a method capable of determining the accurate time to measure non-biodegradable COD(S_I), by the change of transition graphs in the process of measuring microbial OUR, was presented in this study. Influent fractionation is a critical step in the model calibrations. From the results of respirometry on filtered wastewater, the fraction of fermentable and readily biodegradable organic matter(S_F), fermentation products(S_A), inert soluble matter(S_I), slowly biodegradable matter(X_S) and inert particular matter(X_I) was 33.2%, 14.1%, 6.9%, 34.7%, 5.8%, respectively. The active heterotrophic biomass fraction(X_H) was about 5.3%.

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Analysis of activities task using multiple intelligence in middle school 「Technology·Home Economics」 textbooks - Focusing on the 'Dietary Life' unit according to the curriculum of the 2015 revised Practical Arts(Technology·Home Economics) curriculum - (중학교 기술·가정 교과서 다중지능 활용 활동과제 분석 - 2015 개정 실과(기술·가정) 교육과정에 따른 '식생활' 단원을 중심으로 -)

  • Choi, Seong-Youn;Lee, Young-Sun;Choi, Ye-Ji;Joo, Hyun-Jung;Kim, Seung-Hee;Park, Mi-Jeong
    • Journal of Korean Home Economics Education Association
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    • v.30 no.3
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    • pp.19-42
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    • 2018
  • The purpose of this study is to analyze the tasks of 'dietary life' in the textbook developed according to the 2015 revised middle school 「Technology·Home economics」 education curriculum based on the multiple intelligence teaching and learning methods. To accomplish this purpose, 12 textbooks of middle school 「Technology·Home economics」 textbooks were titled "Nutrition and Dietary Behavior of Adolescents", "Planning and Choosing Meals", "Choosing Foods and Safe Cooking" except the questions, the tasks that the students can perform are analyzed based on the teaching and learning methods using multiple intelligences. Analysis methods were analyzed by using contents analysis method, focusing on learning activities, and sub-questions of activities were all included in each activity, and the process of preparing activities on a continuous line was grouped into one. Three people analyzed the activities and proceeded to revise and supplement the analysis standard through consultation. The other three researchers confirmed it. As a result of analyzing 12 kinds of textbooks, the number of activity tasks was 25~74 for each kind of textbooks, and the total number of activities was 527. According to the ratio of multiple intelligences, 35% of the tasks were using logical-mathematical intelligence, and 26.8% of linguistic intelligence, 23% of intrapersonal intelligence, 7.2% of interpersonal intelligence, 3.8% of spatial intelligence, bodily-kinesthetic(2.7%) and musical intelligence(1.5%). On the other hand, it was analyzed that there is no activity task using naturalist intelligence. Except to the naturalist intelligence, general intelligence was utilized. This indicates that the home economics curriculum is a convergence of the home economics curriculum in that it is a reorganization by extracting the contents and methods of other curriculum related to dietary life, is interpreted. This study is expected to provide a framework for various teaching and learning methods to activate students' participation classes and to provide an alternative to realize convergence education in home economics curriculum.

The Analysis of Successional Trends by Topographic Positions in the Natural Deciduous Forest of Mt. Chumbong (점봉산(點鳳産) 일대 천연활엽수림(天然闊葉樹林)의 지형적(地形的) 위치(位置)에 따른 천이(遷移) 경향(傾向) 분석(分析))

  • Lee, Won Sup;Kim, Ji Hong;Jin, Guang Ze
    • Journal of Korean Society of Forest Science
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    • v.89 no.5
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    • pp.655-665
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    • 2000
  • Taking account of the structural variation on species composition by topography, the successional trends were comparatively analyzed for the three topographic positions (valley, mid-slope, and ridge) in the natural deciduous forest of Mt. Chumbong area. The analysis was based upon the subsequent process of generation replacement by understory saplings and seedlings over the overstory trees which will be eventually fallen down. This study adopted the plot sampling method, establishing twenty $20m{\times}20m$ quadrats and collecting vegetation and site data on each different topographic position. The transition matrix model, which was modified from the mathematical theory of Markov chain, was employed to analyze the successional trends and thereafter to predict the overstory species composition in the future for each different topographic position. In valley, the simulation indicated the remarkable decrease in the proportion of species composition of present dominants Quercus mongolica and Fraxinus mandshurica from current 23% and 21% to around 4% of each at the steady state, which is predicted to take less than 200 years. On the other hand, the proportion of such species as Abies holophylla, Acer mono, Tilia amurensis, and Ulmus laciniata will increase at the steady state. In mid-slope, the result showed the remarkable decrease in the proportion of Juglans mandshurica, Kalopanax pictus, and Tilia amurensis from current 15%, 8%, and 15% to 2%, 1%, and 5%, respectively, at steady state predicted to take more than 250 years. In ridge, the current dominant Quercus mongolica was predicted to be decreased dramatically from 58% to 8% at steady state which could be achieved about 200 years. On the contrary, the proportion of Acer mono and Tilia amurensis will be increased from current 4% and 3% to more than 20% and 40%, respectively, at the steady state. Overall results suggested that the study forest is more likely seral rather than climax community. Even though a lot of variation is inevitable due to various kinds of site and vegetation development, the study forest is considered to be more than 200 years away from the steady state or climax in terms of overstory species composition.

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A Case Study on Characteristics of the Mathematics Gifted Children (수학영재의 특성에 관한 사례연구)

  • Kim, Min-Jung;Ryu, Sung-Rim
    • Education of Primary School Mathematics
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    • v.10 no.1 s.19
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    • pp.41-56
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    • 2007
  • Related with the mathematics gifted children the situation of different case studies is the research which is limited in mathematics problem solving process of the most mathematics gifted children. The research which it sees hereupon observes from the scope which is wider the quality of the mathematics gifted children, before the hazard mathematics gifted children whom it sees enter into the mathematics gifted children education center unit life and life after studying living and dismissal of a class from the general school, namely for their general life it leads compared to attitude it observes the reporter it does a quality. For a what kind of interest in the mathematics gifted children, the research leads the family or general class, from the gifted children education center it has it considers encouragement, map and to give a help to good mathematics gifted children education activation, it does. It will reach and to respect with afterwards it set a same three research problem. First, before entering into the mathematics gifted children education center, are the mathematics gifted children what kind of quality? Second, Are the mathematics gifted children what kind of quality for general school hour? Third, Are the mathematics gifted children what kind of quality after dismissal of a class after hour? Being selected in the hazard gifted children education center which solves an up research problem, simple characteristic and approach ease characteristic, by the condition of the permission possibility back it selected 2 person gifted children school boxes which are coming and going. And, before entering into these mathematics gifted children education center, studying life from the general school, life after dismissal of a class it will extend at 1 years, various recording it will ask and it collected direct observation and interview it led against their quality it analyzed. It shared the result which it analyzes with emotional quality, studying conduct qualities, general qualities of the mathematics gifted children and qualities of mathematics gifted children parents. Studies level of the mathematics gifted children parents high facility when them are young from, the interest and helping out which it has were considerable, to advance with the direction where in order for always with great disaster them are proper the map it did. In general quality of the mathematics gifted children from young age the ability which finds a language and a possibility concept superiorly the ability which expresses the thought of oneself logically was superior, the competitive spirit was high, it liked it came reading, a leader role, to reveal a deepening school with the fact that it comes and goes. Also it will burn with their studying conduct quality and it will roll and it did deeply and it arranged knot eagerly, accomplishing which is superior from the field which is various it showed, the originality was superior, the subject attachment power was high quite, oneself it studies it has a devotion the possibility of knowing it was. And, the social characteristic of the friends and is good with their emotional quality and it does there is own reflection and an encouragement at any time and also a confidence, but just as good as the stress also it receives the possibility of knowing it was to him.

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Dynamic Traffic Assignment Using Genetic Algorithm (유전자 알고리즘을 이용한 동적통행배정에 관한 연구)

  • Park, Kyung-Chul;Park, Chang-Ho;Chon, Kyung-Soo;Rhee, Sung-Mo
    • Journal of Korean Society for Geospatial Information Science
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    • v.8 no.1 s.15
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    • pp.51-63
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    • 2000
  • Dynamic traffic assignment(DTA) has been a topic of substantial research during the past decade. While DTA is gradually maturing, many aspects of DTA still need improvement, especially regarding its formulation and solution algerian Recently, with its promise for In(Intelligent Transportation System) and GIS(Geographic Information System) applications, DTA have received increasing attention. This potential also implies higher requirement for DTA modeling, especially regarding its solution efficiency for real-time implementation. But DTA have many mathematical difficulties in searching process due to the complexity of spatial and temporal variables. Although many solution algorithms have been studied, conventional methods cannot iud the solution in case that objective function or constraints is not convex. In this paper, the genetic algorithm to find the solution of DTA is applied and the Merchant-Nemhauser model is used as DTA model because it has a nonconvex constraint set. To handle the nonconvex constraint set the GENOCOP III system which is a kind of the genetic algorithm is used in this study. Results for the sample network have been compared with the results of conventional method.

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Determination of cross section of composite breakwaters with multiple failure modes and system reliability analysis (다중 파괴모드에 의한 혼성제 케이슨의 단면 산정 및 제체에 대한 시스템 신뢰성 해석)

  • Lee, Cheol-Eung;Kim, Sang-Ug;Park, Dong-Heon
    • Journal of Korea Water Resources Association
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    • v.51 no.9
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    • pp.827-837
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    • 2018
  • The stabilities of sliding and overturning of caisson and bearing capacity of mound against eccentric and inclined loads, which possibly happen to a composite caisson breakwaters, have been analyzed by using the technique of multiple failure modes. In deterministic approach, mathematical functions have been first derived from the ultimate limit state equations. Using those functions, the minimum cross section of caisson can straightforwardly be evaluated. By taking a look into some various deterministic analyses, it has been found that the conflict between failure modes can be occurred, such that the stability of bearing capacity of mound decreased as the stability of sliding increased. Therefore, the multiple failure modes for the composite caisson breakwaters should be taken into account simultaneously even in the process of deterministically evaluating the design cross section of caisson. Meanwhile, the reliability analyses on multiple failure modes have been implemented to the cross section determined by the sliding failure mode. It has been shown that the system failure probabilities of the composite breakwater are very behaved differently according to the variation of incident waves. The failure probabilities of system tend also to increase as the crest freeboards of caisson are heightening. The similar behaviors are taken place in cases that the water depths above mound are deepening. Finally, the results of the first-order modal are quite coincided with those of the second-order modal in all conditions of numerical tests performed in this paper. However, the second-order modal have had higher accuracy than the first-order modal. This is mainly due to that some correlations between failure modes can be properly incorporated in the second-order modal. Nevertheless, the first-order modal can also be easily used only when one of failure probabilities among multiple failure modes is extremely larger than others.

A Strategic Approach to Competitiveness of ASEAN's Container Ports in International Logistics (국제물류전략에 있어서 ASEAN의 컨데이너항만 경쟁력에 관한 연구)

  • 김진구;이종인
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2003.05a
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    • pp.273-280
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    • 2003
  • The purpose of this study is to identify and evaluate the competitiveness of ports in ASEAN(Association of Southeast Asian Nations), which plays a leading role in basing the hub of international logistics strategies as a countermeasure in changes of international logistics environments. This region represents most severe competition among Mega hub ports in the world in terms of container cargo throughput at the onset of the 21 st century. The research method in this study accounted for overlapping between attributes, and introduced the HFP method that can perform mathematical operations. The scope of this study was strictly confined to the ports of ASEAN. which cover the top 100 of 350 container ports that were presented in Containerization International Yearbook 2002 with reference to container throughput. The results of this study show Singapore in the number one position. Even compared with major ports in Korea (after getting comparative ratings and applying the same data and evaluation structure), the number one position still goes to Singapore and then Busan(2) and Manila(2), followed by Port Klang(4), Tanjugn Priok(5), Tanjung Perak(6), Bangkok(7), Inchon(8), Laem Chabang(9) and Penang(9). In terms of the main contributions of this study, it is the first empirical study to apply the combined attributes of detailed and representative attributes into the advanced HFP model which was enhanced by the KJ method to evaluate the port competitiveness in ASEAN. Up-to-now, none have comprehensively conducted researches with sophisticated port methodology that has discussed a variety of changes in port development and terminal transfers of major shipping lines. Moreover, through the comparative evaluation between major ports in Korea and ASEAN, the presentation of comparative competitiveness for Korea ports is a great achievement in this study. In order to reinforce this study, it needs further compensative research, including cost factors which could not be applied to modeling the subject ports by lack of consistently qualified in ASEAN.

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The Zhouyi and Artificial Intelligence (『주역』과 인공지능)

  • Bang, In
    • Journal of Korean Philosophical Society
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    • v.145
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    • pp.91-117
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    • 2018
  • This paper aims to clarify the similarities and differences between the Zhouyi and artificial intelligence. The divination of the Zhouyi is rooted in the oldest system of human knowledge, while artificial intelligence stands at the cutting edge of modern scientific revolution. At first sight, there does not appear to be any association that links the one to the another. However, they share the same ground as seen from a semiotic standpoint because both of them depend on the semiotic system as a means of obtaining knowledge. At least four aspects can be pointed out in terms of similarities. First, artificial intelligence and the Zhouyi use artificial language that consists of semiotic signs. Secondly, the principle that enables divination and artificial intelligence lies in imitation and representation. Thirdly, artificial intelligence and the Zhouyi carry out inferences based on mathematical algorithms that adopt the binary system. Fourth, artificial intelligence and the Zhouyi use analogy as a means of obtaining knowledge. However, those similarities do not guarantee that the Zhouyi could arrive at the scientific certainty. Nevertheless, it can give us important insight into the essence of our civilization. The Zhouyi uses intellect in order to get new information about the unknown world. However, it is hard to know what kind of intellect is involved in the process of divination. Likewise, we do not know the fundamental character of artificial intelligence. The intellect hidden in the unknown subject is a mystic and fearful existence to us. Just as the divination of the Zhouyi inspires the sense of reverence toward the supernatural subject, we could not but have fear in front of the invisible subject hidden in artificial intelligence. In the past, traditional philosophy acknowledged the existence of intellect only in conscious beings. Nonetheless, it becomes evident that human civilization ushers into a new epoch. As Ray Kurzweil mentioned, the moment of singularity comes when artificial intelligence surpasses human intelligence. In my viewpoint, the term of singularity can be used for denoting the critical point in which the human species enters into the new phase of civilization. To borrow the term of Shao Yong(邵雍) in the Northern Song Dynasty, the past civilization belongs to the Earlier Heaven(先天), the future civilization belongs to the Later Heaven(後天). Once our civilization passes over the critical point, it is impossible to go back into the past. The opening of the Later Heaven foretold by the religious thinkers in the late period of Joseon Dynasty was a prophecy in its own age, but it is becoming a reality in the present.

Dry reforming of Propane to Syngas over Ni-CeO2/γ-Al2O3 Catalysts in a Packed-bed Plasma Reactor (충전층 플라즈마 반응기에서 Ni-CeO2/γ-Al2O3 촉매를 이용한 프로페인-합성 가스 건식 개질)

  • Sultana, Lamia;Rahman, Md. Shahinur;Sudhakaran, M.S.P.;Hossain, Md. Mokter;Mok, Young Sun
    • Clean Technology
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    • v.25 no.1
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    • pp.81-90
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    • 2019
  • A dielectric barrier discharge (DBD) plasma reactor packed with $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst was used for the dry ($CO_2$) reforming of propane (DRP) to improve the production of syngas (a mixture of $H_2$ and CO) and the catalyst stability. The plasma-catalytic DRP was carried out with either thermally or plasma-reduced $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst at a $C_3H_8/CO_2$ ratio of 1/3 and a total feed gas flow rate of $300mL\;min^{-1}$. The catalytic activities associated with the DRP were evaluated in the range of $500{\sim}600^{\circ}C$. Following the calcination in ambient air, the ${\gamma}-Al_2O_3$ impregnated with the precursor solution ($Ni(NO_3)_2$ and $Ce(NO_3)_2$) was subjected to reduction in an $H_2/Ar$ atmosphere to prepare $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst. The characteristics of the catalysts were examined using X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectrometry (EDS), temperature programmed reduction ($H_2-TPR$), temperature programmed desorption ($H_2-TPD$, $CO_2-TPD$), temperature programmed oxidation (TPO), and Raman spectroscopy. The investigation revealed that the plasma-reduced $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst exhibited superior catalytic activity for the production of syngas, compared to the thermally reduced catalyst. Besides, the plasma-reduced $Ni-CeO_2/{\gamma}-Al_2O_3$ catalyst was found to show long-term catalytic stability with respect to coke resistance that is main concern regarding the DRP process.

Composition of Curriculums and Textbooks for Speed-Related Units in Elementary School (초등학교에서 속력 관련 단원의 교육과정 및 교과서 내용 구성에 관한 논의)

  • Jhun, Youngseok
    • Journal of Korean Elementary Science Education
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    • v.41 no.4
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    • pp.658-672
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    • 2022
  • The unique teaching and learning difficulties of speed-related units in elementary school science are mainly due to the student's lack of mathematical thinking ability and procedural knowledge on speed measurement, and curriculums and textbooks must be constructed with these in mind. To identify the implications of composing a new science curriculum and relevant textbooks, this study reviewed the structure and contents of the speed-related units of three curriculums from the 2007 revised curriculum to the 2015 revised curriculum and the resulting textbooks and examined their relevance in light of the literature. Results showed that the current content carries the risk of making students calculate only the speed of an object through a mechanical algorithm by memorization rather than grasp the multifaceted relation between traveled distance, duration time, and speed. Findings also highlighted the need to reorganize the curriculum and textbooks to offer students the opportunity to learn the meaning of speed step-by-step by visualizing materials such as double number lines and dealing with simple numbers that are easy to calculate and understand intuitively. In addition, this paper discussed the urgency of improving inquiry performance such as process skills by observing and measuring an actual object's movement, displaying it as a graph, and interpreting it rather than conducting data interpretation through investigation. Lastly, although the current curriculum and textbooks emphasize the connection with daily life in their application aspects, they also deal with dynamics-related content somewhat differently from kinematics, which is the main learning content of the unit. Hence, it is necessary to reorganize the contents focusing on cases related to speed so that students can grasp the concept of speed and use it in their everyday lives. With regard to the new curriculum and textbooks, this study proposes that students be provided the opportunity to systematically and deeply study core topics rather than exclude content that is difficult to learn and challenging to teach so that students realize the value of science and enjoy learning it.