• Current Research on Agriculture and Life Sciences
• /
• 제31권4호
• /
• pp.250-255
• /
• 2013

As a renewable nanomaterial, cellulose nanocrystal (CNC) isolated from wood grants excellent mechanical properties in developing high performance nanocomposites. This study was undertaken to compare the reinforcing efficiency of two different CNCs, i.e., cellulose nanowhiskers (CNWs) and cellulose nanofibrils (CNFs) from hardwood bleached kraft pulp (HW-BKP) as reinforcing agent in polyvinyl alcohol (PVA)-based nanocomposite. The CNWs were isolated by sulfuric acid hydrolysis while the CNFs were isolated by 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated oxidation. Based on measurements using transmission electron microscopy, the individual CNWs were about $6.96{\pm}0.87nm$ wide and $178{\pm}55nm$ long, while CNFs were $7.07{\pm}0.99nm$ wide. The incorporation of CNWs and CNFs into the PVA matrix at 5% and 1% levels, respectively, resulted in the maximum tensile strength, indicating different efficiencies of these CNCs in the nanocomposites. Therefore, these results suggest a relationship between the reinforcing potential of CNCs and their physical characteristics, such as their morphology, dimensions, and aspect ratio.

• 대한안전경영과학회지
• /
• 제15권1호
• /
• pp.183-191
• /
• 2013

After the Uruguay Round, Korean agriculture industry has been protected and reared with government grants. However, until now there has been very minimal development to establish a solid export industry which can make the most of the trade agreements in place. There has been much research on ways to expand agricultural exports in order to respond properly to this ever changing environment and sustainable agricultural industry. As all other export industries, an efficient logistics network is paramount in order to allow the agricultural industry to respond to changes in demand and penetrate global markets. The lack of systematic logistics activities such as packaging, transportation, unloading, storage, and information transfer in farms has been a major factor in the inefficiency of the agricultural industry resulting in minimal development. From this perspective, 3PL was proposed and applied as a way to build on the streamlining of export of agricultural logistics system. The Agri 3PL is considered as an efficient agricultural exports method as a new concept connecting producers with exporters.

• 한국사회복지학
• /
• 제44권
• /
• pp.64-90
• /
• 2001

There has been a demand of changing service delivery system for social welfare services, and therefore changing is resource acquisition environment for community social welfare service organizations (CSWSOs). These phenomena are, however, not properly actualized through the CSWSOs. The discrepancy between environmental demand and organizational adaptation seems to result from our lack of understanding those organizations. Based on this understanding, several research problems have been formulated on resource acquisition behaviors of CSWSOs. Empirical data were gathered, and the final sample included 82 social welfare agencies of Pusan province and 122 top/high level agency administrators. The result of data analysis and their implications are as follows: (1) Most of CSWSOs prefer government grants to other financial resources, because government resources can give them more stability than others including private donations and user fees. (2) In order to induce changes in CSWSOs, their stability needs should be properly counted. (3) There is no enough evidence to prove that CSWSOs leaders' personal characteristics have contributed to the behavioral differences on financial resource acquisition among CSWSOs. Rather, there has been enough evidence to prove for influences by institutional environment factors. So, it is recommended that, in order to change behaviors of CSWSOs, the focus should be given to the proper control of those institutional environment factors.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2002년도 춘계종합학술대회
• /
• pp.264-267
• /
• 2002

본 논문에서는 고속 입력 큐 스위치에서 발생하는 중재정보전달지연 현상을 수용하기 위한 고성능 라우팅엔진의 구조를 제안한다. 제안된 고성능 라우팅엔진은 2.5Gbps의 스위치 입출력 포트 속도에 대해 사용자 셀 데이터의 지연 없이 동작한다. 또한 입력버퍼와 중앙중재기 사이에서 발생하는 요청신호와 허가신호의 전송지연을 수용하는 구조로 설계되었다. 중재정보전송지연 현상의 처리 방법으로는 고속 쉬프터를 사용하여 많은 회로의 추가 없이 구현하였다. 라우팅엔진 내의 세부 블록의 파이프라인 처리를 통하여 저 가격 고성능의 입력 버퍼 설계를 실현하였다.

• Journal of Power Electronics
• /
• 제4권4호
• /
• pp.217-227
• /
• 2004

A robust controller that combines the merits of the feed-back, feed-forward and model-following control for induction motor drives utilizing field orientation control is designed in this paper. The proposed controller is a two-degrees-of­freedom (2DOF) integral plus proportional & rate feedback (I-PD) speed controller combined with a model-following (2DOF I-PD MFC) speed controller. A systematic mathematical procedure is derived to find the parameters of the 2DOF I-PD MFC speed controller according to certain specifications for the drive system. Initially, we start with the I-PD feed­back controller design, then we add the feed-forward controller. These two controllers combine to form the 2DOF I-PD speed controller. To realize high dynamic performance for disturbance rejection and set point tracking characterisitics, a MFC controller is designed and added to the 2DOF I-PD controller. This combination is called a 2DOF I-PD MFC speed controller. We then study the effect of the 2DOF I-PD MFC speed controller on the performance of the drive system under different operating conditions. A computer simulation is also run to demonstrate the effectiveness of the proposed controller. The results verify that the proposed 2DOF I-PD MFC controller is more accurate and more reliable in the presence of load disturbance and motor parameter variations than a 2DOF I-PD controller without a MFC. Also, the proposed controller grants rapid and accurate responses to the reference model, regardless of whether a load disturbance is imposed or the induction machine parameters vary.

• Journal of Power Electronics
• /
• 제7권2호
• /
• pp.159-173
• /
• 2007

In this paper, an intelligent sliding-mode position controller (ISMC) for achieving favorable decoupling control and high precision position tracking performance of permanent-magnet synchronous motor (PMSM) servo drives is proposed. The intelligent position controller consists of a sliding-mode position controller (SMC) in the position feed-back loop in addition to an on-line trained fuzzy-neural-network model-following controller (FNNMFC) in the feedforward loop. The intelligent position controller combines the merits of the SMC with robust characteristics and the FNNMFC with on-line learning ability for periodic command tracking of a PMSM servo drive. The theoretical analyses of the sliding-mode position controller are described with a second order switching surface (PID) which is insensitive to parameter uncertainties and external load disturbances. To realize high dynamic performance in disturbance rejection and tracking characteristics, an on-line trained FNNMFC is proposed. The connective weights and membership functions of the FNNMFC are trained on-line according to the model-following error between the outputs of the reference model and the PMSM servo drive system. The FNNMFC generates an adaptive control signal which is added to the SMC output to attain robust model-following characteristics under different operating conditions regardless of parameter uncertainties and load disturbances. A computer simulation is developed to demonstrate the effectiveness of the proposed intelligent sliding mode position controller. The results confirm that the proposed ISMC grants robust performance and precise response to the reference model regardless of load disturbances and PMSM parameter uncertainties.

• 상하수도학회지
• /
• 제31권3호
• /
• pp.205-217
• /
• 2017

This paper tries to show the efficiency of water financing between central and local governments. From the year of 2017, the operation and maintenance costs for change water pipes has been provided by central government as block grants system(RDSA: Regional Development Special Account). Even though the water financing is responsible for local government, water drought and high production cost in poor area affects the quality of life nowadays. Then, fiscal transfer through block grant for water financing has been decided to invest regional SOC. The purpose of the paper sheds light on the function of the block grant for public provision by water financing. The firstly tried empirical results are based on the survey from local governments and ministry of environments. The point of the empirical analysis shows that the local governments does not have proper measurement for unexpected water leakage and termination until now. In a policy manner, the paper raises the issues about benefit principle for water users by the increase of tariffs. In order to do so, the paper investigates the relationship between the water provision and fiscal status of each local governments.

• 한류연구
• /
• 제2권2호
• /
• pp.9-17
• /
• 2023

The primary objectives of this study is to examine and identify the historical factors that have significantly contributed to the growth/ expansion and prosperity of SMEs in the Republic of Korea and to evaluate and assess the impact of historical factors on the economic progress/ development, innovation, and job creation within SMEs in South Korea. To achieve the purpose of the current study, the present author has investigated the comprehensive literature investigation and figured out a total of four Key historical factors of SMEs for Economic Growth in the Republic of Korea, such as (1) Government Policies, (2) Technological Advancements, (3) Access to Finance, (4) International Trade. In conclusion, this study has undertaken a thorough investigation into the four critical historical factors that have significantly affected the development and achievements of SMEs in the Republic of Korea. By addressing a notable gap in current scholarly work, this study not only adds to the existing pool of knowledge but also provides valuable insights for various stakeholders. Practitioners/ professionals should proactively participate in government support initiatives/ programs and financial aid. SMEs can benefit from monetary incentives and donations/ grants intended to stimulate research and development, creativity, and international trade ventures.

• 기술혁신학회지
• /
• 제12권3호
• /
• pp.614-637
• /
• 2009

국가연구개발사업의 투자효율성을 높이기 위해서는 무엇보다도 평가시스템이 잘 갖춰져야 한다. 왜냐하면 혹시라도 특정 평가자에 의해 평가결과가 왜곡 된다면 정부가 바라는 최적의 연구팀을 선정하지 못할 것이고, 이로 인해 바람직한 연구성과를 기대하기 어려울 것이기 때문이다. 현행 국가연구개발사업 평가과정에서는 특정 평가자의 편견(특이치)을 차단하기 위해 대부분 최고/최저점 제외방식을 사용하고 있다. 그러나 우리가 관례적으로 사용하고 있는 이 방식에 한계가 있을 수 있다. 따라서 본 연구에서는 실증분석을 통해 이 방식이 갖고 있는 한계에 대한 문제점을 도출하고, 이를 보완할 수 있는 현실적 대안을 제시함으로써 국가연구개발사업 평가제도의 신뢰성 제고 방안을 모색하였다. 이러한 결과들은 피 평가자들의 평가결과에 대한 수용도 제고 및 국가연구개발사업 효율성 증진에 기여할 수 있을 것이다. 또한 순위결정의 방법론 측면에서 다양한 분야에 도움을 줄 것으로 기대된다.

• 한국비블리아학회지
• /
• 제35권1호
• /
• pp.243-272
• /
• 2024

본 연구는 세계 최대의 의학도서관인 미국 국립의학도서관과 국내 국립의학도서관인 국립의과학지식센터 서비스 비교·분석을 통해 그 개선점 제언을 목적으로 수행되었다. 개선해야 할 핵심적인 서비스는 주제특화 서비스, 지역사회 서비스, 이용자 유형별 서비스, 교육 서비스, 기술 및 시설·공간 서비스, 연구지원 서비스, 마케팅 및 홍보와 협력 서비스이다. 주제특화 서비스와 대국민 서비스는 전문도서관에서도 점차 많은 관심을 가지고 있다. 이용자 유형별 서비스를 통한 접근의 효율성이 필요하며 대상의 제한을 두지 않는 다양한 유형의 교육 서비스도 필요하다. AI, 가상현실 그리고 장애인 지원을 위한 기술·시설·공간 서비스, 연구윤리와 연구 보조금 및 프로그램 중심의 연구지원 서비스, 국내외 관종별도서관, 타 관련 분야 학회, 기관, 지역사회와의 협력 서비스를 통한 마케팅 및 홍보도 필요하다.