• 드라이브 ㆍ 컨트롤
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• 제17권3호
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• pp.26-32
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• 2020

In modern society, the energy-saving problem of industrial vehicles is economically and environmentally critical. Energy savings using the potential energy of forklifts are one of the viable solutions to resolving this problem. The basic concept of this study is to operate the hydraulic motor and recharge the battery using the flow rate from the cylinder when loading heavy objects and lowering the fork. To save energy, the torque and rotational speed of the generator should be optimized according to the load and descent speed to increase efficiency. To this end, we propose a system that optimizes energy saving efficiency by controlling the swashplate angle of the variable hydraulic motor through the GA(Genetic-Algorithm). The results were verified by building and comparing fixed motor models and variable motor models using the AMEsim. The results of the study show that the proposed optimized swashplate angle increases the energy saving efficiency by approximately 6%-8%, depending on the working conditions.

• 자동차안전학회지
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• 제7권1호
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• pp.33-39
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• 2015

This study examined the drivers' acceptance level of various active safety features with Korean drivers on Seoul urban and city roads. The test vehicle, 2013 Cadillac ATS, was equipped with FCA(Forward Collision Alert), LDW(Lane Departure Warning), SBZA(Side Blind Zone Alert), FRPA(Front/Rear Park Assist), RCTA(Rear Cross Traffic Alert), ACC(Adaptive Cruise Control), and AEB(Autonomous Emergency Braking). Participants had chances to run the tests on those systems in the parking lot accompanied by the 106km long stretch of predetermined route including local road and interurban highway in Seoul and Gyeonggi-do under normal traffic flowing environment. After the test, participants completed a series of questionnaires about the features they experienced. The results revealed that RCTA and SBZA systems received more favourable ratings compared to the other features in avoiding crashes. The respondents preferred sound alerts to haptic ones even though haptic warning methods were better in providing directional information.

• 정보과학회 컴퓨팅의 실제 논문지
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• 제21권1호
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• pp.52-57
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• 2015

본 논문에서는 SSD의 TRIM 명령어 처리 성능을 LBA 범위의 특성 및 개수에 따라 분석하고, 그 결과를 바탕으로 Ext4 파일 시스템에서의 TRIM 명령어 처리 성능을 개선하였다. 대부분의 SSD에서 LBA 범위의 크기가 크고, 섹터 번호가 정렬 및 연속되어 있으며, 하나의 TRIM 명령어로 다수의 LBA 범위 정보를 전달할수록 TRIM 명령어의 처리 성능이 증가하는 것으로 나타났다. 한편, 기존의 Ext4 파일 시스템은 이와 같이 다수의 LBA 범위 정보를 전달할 때 그 성능이 더 높음에도 불구하고, 하나의 TRIM 명령어 당 하나의 LBA 범위 정보만 전달하는 문제점을 가지고 있다. 이를 해결하기 위해 하나의 TRIM 명령어로 최대 64개의 LBA 범위 정보를 전달하도록 Ext4 파일 시스템을 개선하였고, Filebench를 이용한 성능 평가에서 파일 삭제 성능이 최대 35% 증가하는 것을 확인하였다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 춘계학술대회 논문집
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• pp.266-269
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• 2009

Iron-based soft magnetic materials are widely used as cores, such as transformer transformers, motors, and generators. Reducing losses generated from soft magnetic materials of these applications results in improving energy conversion efficiency. Recently, the new P/M soft magnetic material realized an energy loss of 68 W/kg with a drive magnetic flux of 1 T, at a frequency of 1 kHz, rivaling general-purpose electromagnetic steel sheet in the low frequency range of 200 Hz to 1 kHz. In this research, the effect of rolling parameters on soft magnetic properties of Fe-based powder cores was investigated. The Fe-based soft magnetic plates were produced by the hot powder rolling process after both pure Fe and Fe-4%Si powders were canned, evacuated, and sealed in Cu can. The soft magnetic properties such as energy loss and coercive power were measured by B-H curve analyzer. The soft magnetic properties of rolled sheets were measured under conditions of a magnetic flux density of 1 T at a frequency of 200 kHz. It was found that rolling reduction ratio is the most effective parameter on reducing both energy loss and coercivity because of increasing aspect ratio with reduction ratio. By increasing aspect ratio from 1 to 9 through hot rolling of pure Fe powder, a significant loss reduction of one-third that of SPS sample was achieved.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.550-551
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• 2013

Large-area RF-driven ion source is being developed at Germany for the heating and current drive of ITER plasmas. Negative hydrogen (deuterium) ion sources are major components of neutral beam injection systems in future large-scale fusion experiments such as ITER and DEMO. RF ion sources for the production of positive hydrogen ions have been successfully developed at IPP (Max-Planck- Institute for Plasma Physics, Garching) for ASDEX-U and W7-AS neutral beam injection (NBI) systems. In recent, the first NBI system (NBI-1) has been developed successfully for the KSTAR. The first and second long-pulse ion sources (LPIS-1 and LPIS-2) of NBI-1 system consist of a magnetic bucket plasma generator with multi-pole cusp fields, filament heating structure, and a set of tetrode accelerators with circular apertures. There is a development plan of large-area RF ion source at KAERI to extract the positive ions, which can be used for the second NBI (NBI-2) system of KSTAR, and to extract the negative ions for future fusion devices such as ITER and K-DEMO. The large-area RF ion source consists of a driver region, including a helical antenna (6-turn copper tube with an outer diameter of 6 mm) and a discharge chamber (ceramic and/or quartz tubes with an inner diameter of 200 mm, a height of 150 mm, and a thickness of 8 mm), and an expansion region (magnetic bucket of prototype LPIS in the KAERI). RF power can be transferred up to 10 kW with a fixed frequency of 2 MHz through a matching circuit (auto- and manual-matching apparatus). Argon gas is commonly injected to the initial ignition of RF plasma discharge, and then hydrogen gas instead of argon gas is finally injected for the RF plasma sustainment. The uniformities of plasma density and electron temperature at the lowest area of expansion region (a distance of 300 mm from the driver region) are measured by using two electrostatic probes in the directions of short- and long-dimension of expansion region.

• 토지주택연구
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• 제8권2호
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• pp.33-53
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• 2017

The UK Government's approach to how to deliver regeneration in its towns and cities has changed considerably in recent years. Traditionally, urban regeneration policy focused on reversing physical, economic and social decline in an area where market forces would not do this without intervention. Since 2010 urban regeneration has become a vital part of the Government's approach to increasing local growth and competitiveness and building a strong and balanced economy. The current emphasis is on a place-based approach to regeneration that builds on the particular strengths of different places to drive growth and addresses the factors that hold them back. This paper outlines the key features of current UK urban regeneration policy and how interventions to support regeneration and growth are being pursued at different spatial scales to ensure all parts of the country benefit. They include pan regional initiatives like the Northern Powerhouse and Midlands Way, to groups of local authorities operating at a sub regional level (combined authorities/city regions), Local Enterprise Partnerships, and a variety of smaller scale programmes delivering regeneration in areas of economic and social decline. The paper explains some of the policy instruments and funding programmes available to support regeneration, and provides case studies of some major urban regeneration projects that illustrate the new approach including housing and infrastructure improvements like the planned High Speed Rail 2 line. These are supporting regeneration through the creation of strategic partnerships involving government, places and investors. The paper concludes with some lessons from past and future regeneration schemes to improve their effectiveness and impact on places and enhance local growth potential.

• 산경연구논집
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• 제10권7호
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• pp.49-58
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• 2019

Purpose - Previous studies on the influence of appeal types of advertising messages on pro-social behavior have shown inconsistent results. The purpose of this study is to examine whether the appeal type of advertising affects consumer's prosocial behavior. In particular, the authors investigated whether the social exclusion moderates the relationship between the appeal type of advertising and prosocial behavior. Research design, data and Methodology - To verify the hypothesis, two experimental study were conducted. The experimental study was 2(appeal type : self-benefit vs. other-benefit) by 2(social exclusion : being ignored vs. being rejected) between-subject design. Participants were randomly assigned to one of four conditions. The experiment was conducted using a computer. First, the participants was exposed to the advertising image used in the social campaign, and then responded to questions about social behavior. The participants completed the experiment after further responding to the item for manipulation check and demographic measure. The experiment took about 10 minutes in total. Results - In Study 1, a global warming campaign with participation intention variable, other-benefit ads rather than self-benefit ads drive consumers who feel socially rejected to be more willing and likely to participate, but consumers who feel socially ignored are more likely to participate the campaign in self-benefit ad than other-benefit ad. Study 2 replicates the findings, a child poverty relief campaign with an amount-to-donate variable: consumers who feel explicitly rejected allocate more dollars to the charity in response to other-benefit rather than self-benefit ads, but consumers who being ignored are willing to donate more money. Conclusion - This study has theoretical contribution in that it expands existing theories by explaining the existing inconsistent results of the message appeal influence on pro-social behavior through new control variables. In addition, the results have important managerial implications, suggesting marketers should tailor their marketing message to match the consumer situation.

• 한국지능시스템학회논문지
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• 제24권1호
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• pp.52-57
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• 2014

본 논문은 두 바퀴 이동로봇의 주행에 있어서 주어진 경로를 물리적 제한을 만족하면서 주행하는 관절 공간 궤적 생성방법을 실시간 운영체제를 이용하여 구현함으로써 실시간 제어 방법에 대하여 연구하였다. 경로계획에서 이동로봇의 방향을 고려하기 위하여 베지어곡선을 이용하였으며, 컨볼루션 연산자를 이용하여 로봇의 두 바퀴의 속도의 제한을 만족시켰다. 관절 공간의 궤적 생성과 생성된 궤적에 대한 속도명령, 그리고 엔코더 값 감시 등 실시간 태스크를 주기적 태스크로 구현하였으며 동기화를 위하여 실시간 메커니즘인 이벤트 플래그를 이용하여 구현하였다. 실제 로봇에 실시간 태스크를 구현하여 속도명령의 실시간성과 이에 따른 이동로봇의 주행실험 결과를 이용하여 궤적 추종 성능을 비실시간 시스템과 분석하였다. 결과를 통하여 실시간 성을 요구하는 제어시스템에서 실시간 다중 태스크 시스템의 유용성을 검증하였다.

• 한국교육논총
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• 제40권3호
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• pp.39-65
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• 2019

생성의 입장에서 바라보는 죽음은 소수 교육철학의 형성에 기여한다. 소수 문학에 대한 탐구는 이 관계를 확고하게 해준다. 들뢰즈와 가타리의 소수 문학이란 소수 언어로 쓰인 문학을 말하는 것이 아니라 오히려 소수자들이 다수언어로 만들어내는 문학을 말한다. 그들은 카프카의 작품들을 그 전형으로 내세운다. 카프카의 작품들은 궁극적으로 이 생성(devenir)으로서의 죽음을 말한다. 죽음과 소수 문학은 강도(intensité)라는 이론적 도구를 공유함으로써 서로를 전제하는 것으로 파악된다. 소수 교육철학은 이런 주장을 좇아 그 가능성이 제기된다. 이는 잘 포장된 상품으로서의 지식을 전달하는 일에만 만족하는 현대 교육철학자들의 정체성에 의문을 제기하고, 특정한 방식으로만 철학자들을 독해하도록 강요하는 주류 교육철학에 맞선다. 우리는 이 가능성을 정동(affect)으로서의 언어에 입각한 교육활동을 통해 제기해 볼 수 있다.

• Spatial Information Research
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• 제5권2호
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• pp.185-194
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• 1997

의사결정지원체계의 한 분류인 공간의사결정지원체계(SDSS)는 지리정보체계(GIS)와 의사결정지원체계(DSS)의 결합으로 이루어진다. 계획지원체계(PSS)는 공간의사결정지원체계의 기능에 지리정보체계보다 고차원의 공간분석기능과 시간기능을 추가하여 구성된다. 본 연구는 계획가와 기술자가 적정 하수도 관경대안을 생성할 수 있는 계획지원체계의 개발에 관한 연구이다. 적정 하수도관경 결정을 위한 계획지원체계(PSS/GSS)의 이론적인 근거는 토지이용계획과 개발이 우오수관로의 수요를 유발한다는데 있다. 공급, 수요, 대안생성, 그리고 평가의 4단계를 통하여 PSS/GSS는 하수관거 생성의 기본계획, 기본설계,실시설계단계를 통합한다. GIS와 사용자 인터페이스는 하수도관망 배치, 하수량 산장, 그리고 생성된 대안의 도시에 유용한 수단이다. 모의에 ?나 하수도관경결정모델은 초리관망을 생성하낟. 사용자는 하수도관망의직접조작에 의하거나 하수도관경결정모델의 매개변수 조정에 의하여 대안을 생성할 수 있으며 이러한 대안의 타당성은 하수도관경결정모델에 의하여 점검된다.