• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제9권10호
• /
• pp.3921-3944
• /
• 2015

Currently Energy-Saving (ES) methods in cellular networks could be improved, as compensation method for irregular Base Station (BS) deployment is not effective, most regional ES algorithm is complex, and performance decline caused by ES action is not evaluated well. To resolve above issues, a low-complexity energy efficient BS cooperation mechanism for Long Time Evolution (LTE) networks is proposed. The mechanism firstly models the ES optimization problem with coverage, resource, power and Quality of Service (QoS) constraints. To resolve the problem with low complexity, it is decomposed into two sub-problems: BS Mode Determination (BMD) problem and User Association Optimization (UAO) problem. To resolve BMD, regional dynamic multi-stage algorithms with BS cooperation pair taking account of load and geographic topology is analyzed. And then a distributed heuristic algorithm guaranteeing user QoS is adopted to resolve UAO. The mechanism is simulated under four LTE scenarios. Comparing to other algorithms, results show that the mechanism can obtain better energy efficiency with acceptable coverage, throughput, and QoS performance.

• 한국초등과학교육학회지:초등과학교육
• /
• 제43권1호
• /
• pp.136-147
• /
• 2024

최근 과학교육에서는 실생활에서 발생하는 여러 문제나 위험에 대해서 과학적으로 인식하여 대응할 수 있는 '과학적 참여와 실천' 역량을 기를 수 있는 수업이 강조되고 있다. 본 연구에서는 초등 예비교사들이 설계한 '과학적 참여와 실천' 수업의 특징을 살펴보기 위하여, 예비교사들이 작성한 교수학습 과정 안을 분석하고 시사점을 도출하였다. 이를 위해, 2022 개정 과학과 교육과정 초등학교 3~4학년군에 제시된 '소음'과 관련한 성취기준에 대해서 예비교사들이 설계한 교수학습 과정안을 수집하고, '문제 인식', '자료수집 및 분석', '실행 및 공유' 관점에서 나타나는 특징을 분석하였다. 연구 결과, 초등 예비교사들이 설계한 교수학습 과정안에서는 '문제해결형', '탐구형', '조사형', '행동촉구형' 활동이라는 4가지 특징이 도출되었다. 이렇게 도출된 4가지 특징들은 다양한 수업의 맥락에 따라 2~3가지 특징이 함께 결합되기도 하고, 한 수업에서 한 가지 특징만 나타나는 경우도 있었다. 이러한 결과를 토대로, 초등학생을 위한 과학적 참여와 실천 수업을 설계하는 교사들을 조력하기 위한 시사점을 교수학습 방법적 측면과 교사교육적 측면으로 나누어 논의하였다.

• Wind and Structures
• /
• 제27권1호
• /
• pp.11-27
• /
• 2018

The straight-cone steel cooling tower is a novel type of structure, which has a distinct aerodynamic distribution on the internal surface of the tower cylinder compared with conventional hyperbolic concrete cooling towers. Especially in the extreme weather conditions of strong wind and heavy rain, heavy rain also has a direct impact on aerodynamic force on the internal surface and changes the turbulence effect of pulsating wind, but existing studies mainly focus on the impact effect brought by wind-driven rain to structure surface. In addition, for the indirect air cooled cooling tower, different additional ventilation rate of shutters produces a considerable interference to air movement inside the tower and also to the action mechanism of loads. To solve the problem, a straight-cone steel cooling towerstanding 189 m high and currently being constructed is taken as the research object in this study. The algorithm for two-way coupling between wind and rain is adopted. Simulation of wind field and raindrops is performed with continuous phase and discrete phase models, respectively, under the general principles of computational fluid dynamics (CFD). Firstly, the rule of influence of 9 combinations of wind sped and rainfall intensity on flow field mechanism, the volume of wind-driven rain, additional action force of raindrops and equivalent internal pressure coefficient of the tower cylinder is analyzed. On this basis, the internal pressures of the cooling tower under the most unfavorable working condition are compared between four ventilation rates of shutters (0%, 15%, 30% and 100%). The results show that the 3D effect of equivalent internal pressure coefficient is the most significant when considering two-way coupling between wind and rain. Additional load imposed by raindrops on the internal surface of the tower accounts for an extremely small proportion of total wind load, the maximum being only 0.245%. This occurs under the combination of 20 m/s wind velocity and 200 mm/h rainfall intensity. Ventilation rate of shutters not only changes the air movement inside the tower, but also affects the accumulated amount and distribution of raindrops on the internal surface.

• 한방안이비인후피부과학회지
• /
• 제16권1호
• /
• pp.168-178
• /
• 2003

Strabismus refers to a extra-ocular muscle imbalance that results in improper alignment of the visual axes of two eyes. It may be divided into paralytic and non-paralytic strabismus. Paralytic strabismus is primarily a neurological problem: non-paralytic strabismus is more strictly an ophthalmologic problem. This case report focuses on paralytic strabismus resulting from palsies of the third and the sixth cranial nerves, respectively. Oculomotor nerve palsies result in binocular diplopia with characteristic patterns of strabismus. Oculomotor nerve provides motor and parasympathetic innervation to the eyes. Acquired oculomotor nerve palsies are not uncommon. Injury to the third nerve may result in complete or partial dysfunction. Complete third nerve palsy is manifested by ptosis, dilated pupil, an eye that is deviated down and out in primary position, and limited adduction, elevation, and depression. Patients with unilateral sixth nerve palsy complain of binocular, horizontal diplopia esotropia in the primary position due to unopposed action of the medial rectus and limitation of abduction due to weakness of the lateral rectus. Diplopia is worse in the direction of the paretic lateral rectus muscle. Paralytic strabismus are treated, based on the theory of Oriental medicine. with berbal medicines having gun-bi(健脾), bae-to(培土), gue-pung(祛風) effect of acupuncture around the eyes and etc. We describe a 63-year-old woman with complete the 3rd cranial nerve palsy and a 32-year-old woman with the unilateral 6th cranial nerve palsy who treated with acupuncture and herbal medicines and showed complete recovery.

• 통합자연과학논문집
• /
• 제12권2호
• /
• pp.58-68
• /
• 2019

Critical thinking is essential to implementing the nursing process requiring timely decision making. The study examined the effects of a critical thinking course for nurses in the RN-BSN program. The study used a pre- and post-test design with a control group. The experimental group was a convenience sample of 24 working nurses attending a health college. The control group was 24 fellow nurses. The nursing process-based critical thinking course was provided to the experimental group two and half hours a week for 8 weeks. Teaching methods included lectures followed by a summary and quiz, brainstorming and action learning, and lecturer feedback. A pamphlet about views of professional occupation was provided to the control group. The data were collected using self-report questionnaires and analyzed to examine differences in the test scores before and after the intervention. The scores of critical thinking disposition, problem-solving process, and clinical competence increased significantly in the experimental group but did not in the control group. The difference between the two groups was also statistically significant in critical thinking disposition, problem-solving process, and clinical competence. It is necessary that a robust educational program or training to enhance critical thinking ability of nurses are provided in clinical settings and that nurses keep going on thinking critically in their practice.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제15권8호
• /
• pp.2993-3010
• /
• 2021

The job shop scheduling problem (JSSP) plays a critical role in smart manufacturing, an effective JSSP scheduler could save time cost and increase productivity. Conventional methods are very time-consumption and cannot deal with complicated JSSP instances as it uses one optimal algorithm to solve JSSP. This paper proposes an effective scheduler based on deep learning technology named self-supervised long-short term memory (SS-LSTM) to handle complex JSSP accurately. First, using the optimal method to generate sufficient training samples in small-scale JSSP. SS-LSTM is then applied to extract rich feature representations from generated training samples and decide the next action. In the proposed SS-LSTM, two channels are employed to reflect the full production statues. Specifically, the detailed-level channel records 18 detailed product information while the system-level channel reflects the type of whole system states identified by the k-means algorithm. Moreover, adopting a self-supervised mechanism with LSTM autoencoder to keep high feature extraction capacity simultaneously ensuring the reliable feature representative ability. The authors implemented, trained, and compared the proposed method with the other leading learning-based methods on some complicated JSSP instances. The experimental results have confirmed the effectiveness and priority of the proposed method for solving complex JSSP instances in terms of make-span.

• 품질경영학회지
• /
• 제40권4호
• /
• pp.467-480
• /
• 2012

Purpose: This paper introduces new 2-of-3 main and supplementary runs rules to increase the performance of the classical $\bar{X}$ control chart for detecting small process shifts. Methods: The proposed runs rules are compared with other competitive runs rules by numerical experiments. Nonlinear optimization problem to minimize the out-of-control ARL at a specified shift of process mean for determining action and warning limits at a time is formulated and a procedure to find two limits is illustrated with a numerical example. Results: The proposed 2-of-3 main and supplementary runs rules demonstrate an improved performance over other runs rules in detecting a sudden shift of process mean by simultaneous changes of mean and standard deviation. Conclusion: To increase the performance in the detection of small to moderate shifts, the proposed runs rules will be used with $\bar{X}$ control charts.

• Asia pacific journal of information systems
• /
• 제2권2호
• /
• pp.31-54
• /
• 1992

Generating an action plan and obtaining commitment to achieve it is desired in organizations, but not always achieved. Whatever the reason, there is a room for an improved approach to decision making, so that people can arrive at a common understanding of a problem and commitment to action. Those are the purposes of a Decision Conferencing(DC). A DC, one example of single workstation-based GDSSs, is a two-day session attended by a group of people who attempt to resolve important issues of concern to their organization with the help of group facilitation techniques and decision analytic computer modelling. The interchange of differing perspectives on the issues is encouraged by the facilitator who attends to group processes but does not contribute to the content of discussions. Decision analysis provides a variety of structures for modelling the differing perspectives. Information and value judgements are incorporated in these models, whose results usually reveal new, higher-level perspectives on the issues. Information technology is needed to combine the part of the model and to facilitate on-the-spot replay of results. The experimental case study in this paper shows that how a DC can help a Korea's trading company to develop new, corporate level resource allocation strategies which are based on improved consensus among competing participants.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2005년도 ICCAS
• /
• pp.825-829
• /
• 2005

This paper presents an approach for designing a fuzzy logic-based adaptive SVC damping In controller for damping low frequency power oscillations. Power systems are often subject to low Frequency electro-mechanical oscillations resulting from electrical disturbances. Generally, power system stabilizers are designed to provide damping against this kind of oscillations. Another means to achieve damping is to design supplementary damping controllers that are equipped with SVC. Various approaches are available for designing such controllers, many of which are based on the concepts of damping torque and others which treat the damping controller design as a generic control problem and apply various control theories on it. In our proposed approach, linear optimal controllers are designed and then a fuzzy logic tuning mechanism is constructed to generate a single control signal. The controller uses the system operating condition and a fuzzy logic signal tuner to blend the control signals generated by two linear controllers, which are designed using an optimal control method. First, we design damping controllers for the two extreme conditions; the control action for intermediate conditions is determined by the fuzzy logic tuner. The more the operating condition belongs to one of the two fuzzy sets, the stronger the contribution of the control signal from that set in the output signal. Simulation studies done on a one-machine infinite-bus and a four-machine two-area test system, show that the proposed fuzzy adaptive damping SVC controller effectively enhances the damping of low frequency oscillations.

• 한국가정과교육학회지
• /
• 제32권2호
• /
• pp.117-139
• /
• 2020

이 연구의 목적은 세 가지 행동체계를 융합한 초·중·고등학교 가정교과 식생활 교육과정의 내용체계를 개발하여 가정교과에서의 융합교육 방안을 마련하는 데 목적이 있다. 이러한 목적을 이루기 위해서 문헌 고찰을 통해 세 행동체계를 융합한 초·중·고등학교 식생활 교육과정의 특징, 개발의 중점사항, 핵심역량, 목표를 도출하였고, 국내외 식생활교육 문헌, 국내외 가정과교육과정과 교과서를 고찰하여 항구적 문제와 하위 실천적 문제를 설정하고, 내용 요소를 선정하였다. 개발된 교육과정의 내용체계가 타당한지 전문가 타당도 검사를 하여 수정·보완하였고, 세 행동체계를 융합한 중학교 가정교과 식생활 교육과정의 성취기준을 개발하였다. 세 행동체계를 융합한 초·중·고 가정교과 식생활 교육과정의 내용 체계는 실천적 문제를 중심으로 되어있으며, 항구적 문제는 '건강한 식생활을 실천하기 위해 무엇을 해야 하는가?'이다. 이 교육과정의 영역은 5가지로 '건강과 식생활', '식단계획', '식품 구매와 관리', '조리', '식사'이며, 이 영역이 '개인과 가족', '사회'로 교육과정의 범위가 반복적으로 확장되어 있다. 이에 따라 5개 영역의 실천적 문제는 초·중·고등학교 급별, 두 차원(개인과 가족, 사회)으로 10개씩의 실천적 문제로 구성되어 있으며, 계열화의 원리가 적용되어 실천적 문제와 내용 요소가 나선형적 계열화가 되어있다. 이 교육과정의 내용 체계를 우리나라 2015 초등학교 실과와 중·고등학교 기술·가정과, 가정과학 교육과정의 식생활 영역 성취기준 및 학습 요소와 비교한 결과, 2015 개정 교육과정의 내용을 모두 포함하면서 더 추가된 내용이 있었다.