• 제목/요약/키워드: Lower System

검색결과 11,098건 처리시간 0.043초

초등학교 저학년 아동을 위한 기초적 수학 능력의 신장 방안 (The measures for nursing the foundational math skills of the lower grade elementary school children)

  • 이순주
    • 한국수학교육학회지시리즈C:초등수학교육
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    • 제6권2호
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    • pp.75-84
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    • 2002
  • After entering an elementary school, in fact, a number of children regard mathematics as one of very difficult subjects because of its abstractiveness. This is caused by the fact that their basic thinking power is not yet formed or they can not understand the special quality of mathematics. So this article emphasizes the need to build up the higher logical thought and a basic mathematical concept at the lower grade elementary school stage in which the loaming activity on mathematics begins in earnest, that is, at the stage before having an experience on the calculating activity using numbers. But at present the lower grade elementary school students in our country do not understand the special quality of mathematics composed of a various symbolic system and lay stress upon mathematics learning attached to the calculative activity. In order to make the right mathematical concept of the lower grade elementary school, the basic knowledge and ability as follows is sure to be formed. 1) the foundational logical manipulation activity and knowledge 2) the using ability of the sign and symbolic system At the stage on which mathematics learning activity begins, it is a very important task to make the right concept of the abstractive math and nurse the capability for finding mathematical relations covered under the sign system through the continuos loaming activity on . Through the basic logical manipulation activity and the game activity of sign for lower grade elementary school students mentioned in this article, they can not only foster the higher level logical thinking power and the foundational calculative ability but also bring up the interest on the activity of establishing a new problem solving strategy.

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선체 표면 공사시 발생하는 분진 수거 장치 개발에 관한 연구 (A Study on the Development of Dust Collection System for Hull Repair)

  • 여석준
    • 동력기계공학회지
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    • 제8권2호
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    • pp.31-38
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    • 2004
  • The main purpose of this study is to investigate the characteristics of hybrid collection system combined with centrifugal force of cyclone and filtration of bag filter in one unit system. The experiment and numerical simulation are executed for the analysis of collection efficiency and pressure drop characteristics of hybrid system in comparison with those of a general fabric bag filter with the various experimental parameters such as inlet velocity(filtration velocity), dust concentration and dust type, etc.. In present system, dust particles tangentially coming into the system body are controlled by the centrifugal force effect, and the next collection is made out by the filtration mechanism in the fabric filter media. Therefore, the effective first collection causes the decrease of dust loading on the fabric filter, and it presents quite a lower pressure drop of fabric filter than that of a general fabric filter. At the inlet velocity, $21{\sim}27m/sec$ and inlet concentration(fly ash) $300mg/m^3$, pressure drops through the filter media of hybrid system are shown lower as $10{\sim}22mmH_2O$ comparing to those($17{\sim}33mmH_2O$) of a general fabric bag filter.

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FUNDAMENTAL THEOREM OF UPPER AND LOWER SOLUTIONS FOR A CLASS OF SINGULAR (p1, p2)-LAPLACIAN SYSTEMS

  • XU, XIANGHUI;LEE, YONG-HOON
    • East Asian mathematical journal
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    • 제31권5호
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    • pp.727-735
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    • 2015
  • We introduce the fundamental theorem of upper and lower solutions for a class of singular ($p_1,\;p_2$)-Laplacian systems and give the proof by using the Schauder fixed point theorem. It will play an important role to study the existence of solutions.

일반하한제약을 갖는 일반연속 다중선택 선형배낭문제의 해법연구 (The Generalized Continuous Multiple-Choice Linear Knapsack Problem with Generalized Lower Bound Constraints)

  • 원중연
    • 산업경영시스템학회지
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    • 제21권45호
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    • pp.291-299
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    • 1998
  • We present a variant for the generalized continuous multiple-choice knapsack problem[1], which additionally has the well-known generalized lower bound constraints. The presented problem is characterized by some variables which only belong to the simple upper bound constraints and the others which are partitioned into both the continuous multiple-choice constraints and the generalized lower bound constraints. By exploiting some extended structural properties, an efficient algorithm of order Ο($n^2$1og n) is developed, where n is the total number of variables. A numerical example is presented.

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단일 구동부를 갖는 2축 도립 진자를 위한 제어기 구현 (An implementation of a controller for a double inverted pendulum with a single actuator)

  • 남노현;이건영
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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    • pp.257-260
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    • 1997
  • In this paper, the double inverted pendulum having a single actuator is built and the controller for the system is proposed. The lower link is hinged on the plate to free for rotation in the x-z plane. The upper link is connected to the lower link through a DC motor. The double inverted pendulum built can be kept upright posture by controlling the position of the upper link even though the proposed inverted pendulum has no actuator in lower hinge. The algorithm to control the inverted pendulum is consisted of a state feedback controller within a linearizable range and a fuzzy logic controller coupled with a feedback linearization control for the rest of the range. Concept of the virtual work is employed to drive the linearlized model for the state feedback controller. The feedback linearization controller drives a DC motor with the modified reference joint angle from the fuzzy controller which adjusts a upright posture of a proposed pendulum system. Finally, the experiments are conducted to show the validity of the proposed controller.

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The Effects of PNF Rhythmic Dance on the Change of Static Balance Ability in Young Adults

  • Park, Byeong-Jin;An, Byeong-Min;Yu, Sook-Kyeong;Lee, Han-Sol;Hwang, Youn-Jung;Kim, Sik-Hyun
    • 국제물리치료학회지
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    • 제1권2호
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    • pp.176-184
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    • 2010
  • This study was to investigate the effects of upper and lower limb composing patterns of PNF(proprioceptive neuromuscular facilitation) on the static balance ability by 20 subjects for 6 weeks. This study was measured left one leg standing and right one leg standing with closed eyes on Good Balance system. These results led us to the conclusion that the mean speed of X, Y direction, COP(center of Pressure) velocity moment showed a statistical decrease when applying post-exercise. The above results from this study indicated that upper and lower limb composing patterns of PNF exercise has improved the static balance ability. As a result, this study showed that upper and lower limb composing patterns exercise improve the ability of balance in young adults. Based on this study, it may be applied to old people.

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다발성 신경병증에 대한 한방 치험 1례 (A Clinical Report of Polyneuropathy Treated with Korean Medical Treatment)

  • 손변우;정해룡;황원덕
    • 대한한방내과학회지
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    • 제37권5호
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    • pp.698-703
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    • 2016
  • Objective: To describe the effects of Korean medical treatment on a 51-year-old male patient with polyneuropathy and chief complaints of lower limb paralysis and dysarthria. Methods: The Toronto Clinical Neuropathy Scoring System (TCNSS) was used to evaluate the function of the lower limb and the symptoms of the patient were observed daily. We applied herbal medication and acupuncture daily, depending on the patient’s symptoms. Results: After the treatment, the TCNSS score was improved. Conclusions: In this case, Korean medical therapy was effective in improving lower limb function.

주간 하늘에 노출된 평판에 의한 복사냉각 실험 (Radiant Cooling by the Plate Viewing the Daytime Sky)

  • 변기홍
    • 한국태양에너지학회 논문집
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    • 제27권4호
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    • pp.11-17
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    • 2007
  • The purpose of this study is to check whether the plate temperature could be lower than the surrounding air by using the radiant cooling during the day time in summer at Seoul. Without an insolation shield as this experiment was performed, a few cases were found. The temperatures of the black painted plate are lower than those of the aluminium film coated plate if the following condition exist; no or small insolation over the plate, the wind velocity less than around 2 m/s, and clear sky However if there are insolation over the plate, the temperatures of the aluminium coated plate are lower than the black painted plate. Also, as the wind velocity increases, the plate temperature decreases faster. The temperature response of the small system is much faster than the large system.

X, Y 방향에 따른 상부벽식-하부골조의 비선형 정적응답특성 (The Response Characteristics of Nonlinear Pushover Analysis of Upper Wall-Lower Frame System with X and Y-Directions)

  • 강병두;전대한;김재웅
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2003년도 가을 학술발표회 논문집
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    • pp.209-216
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    • 2003
  • The purpose of this study is to investigate the response characteristics of pushover analysis of upper wall-lower frame system with X and Y-directions' lateral load Pushover analysis estimates initial elastic stiffness, post-yielding stiffness, and plastic hinges on each story of structures through three-dimensional nonlinear analysis program. The conclusions of this study are as follows; (1) As a result of pushover analysis, the magnitude of nonlinear response and distribution of yield hinge in lower structure are similar with both X and Y directions, but not in upper structure because of different relative stiffness. (2) The maximum drift ratio of roof is larger for X-direction than for Y-direction with respect to magnitude of shear wall areas in upper structure.

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심박변이도를 통한 급성, 기능성, 기질성 소화불량증의 비교연구 (Comparative Study of Acute Dyspepsia, Functional Dyspepsia, Organic Dyspepsia by HRV(Heart Rate Variability))

  • 김효진;김보경;김원일
    • 동의신경정신과학회지
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    • 제21권2호
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    • pp.75-85
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    • 2010
  • Objectives : This study was designed to evaluate the correlation between patterns of dyspepsia(acute dyspepsia, functional dyspepsia, dyspepsia with the organic disease) and autonomic nerve system dysfunction using HRV analysis. Methods : The patient group consisted of 88 patients diagnosed as a dyspepsia (Acute dyspepsia group-35 patients, Functional dyspepsia group-28 patients, Dyspepsia with the organic disease group-28 patients) who visited in the Oriental Medical Hospital of Dong-eui University from 2005.3.OO to 2008.8.OO. And the control group consisted of 33 patients diagnosed as a normal state of stomach during the same period. We checked HRV of the 4 groups over 5 minutes and compared the HRV index between groups. Results : 1. HF, LF, VLF and TP were significantly lower in the acute dyspepsia, functional dyspepsia and organic dyspepsia patient group than in the control group. 2. HF, LF, VLF and TP were higher in the acute dyspepsia patient group than in the organic dyspepsia patient group, but the differences were not statistically significant. 3. HF, LF, VLF and TP were higher in the acute dyspepsia patient group than in the functional dyspepsia patient group, but the differences were not statistically significant. 4. HF, LF, VLF and TP were lower in the functional dyspepsia patient group than in the organic dyspepsia patient group, but the differences were not statistically significant. Conclusions : Compared to the control group, all of the dyspepsia patient groups showed the tendency that the overall activity of the autonomic nervous system and the activity of sympathetic nerves decreased. Although there was no significant difference in the suppression of the autonomic nervous system, chronic dyspepsia patient group was lower than acute dyspepsia patient group, functional dyspepsia patient group was lower than the organic dyspepsia patient group in HRV.