• Membrane and Water Treatment
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• 제8권5호
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• pp.449-462
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• 2017

Direct treatment of municipal wastewater by forward osmosis (FO) process was evaluated in terms of water flux decline, reverse salt diffusion, pollutants rejection and concentration efficiency by using synthetic seawater as the draw solution. It was found that when operating in PRO mode (active layer facing the draw solution), although the FO membrane exhibited higher osmotic water flux, more severe flux decline and reverse salt diffusion was also observed due to the more severe fouling of pollutants in the membrane support layer and accompanied fouling enhanced concentration polarization. In addition, although the water flux decline was shown to be lower for the FO mode (active layer facing the feed solution), irreversible membrane fouling was identified in both PRO and FO modes as the water flux cannot be restored to the initial value by physical flushing, highlighting the necessity of chemical cleaning in long-term operation. During the 7 cycles of filtration conducted in the experiments, the FO membrane exhibited considerably high rejection for TOC, COD, TP and $NH_4{^+}-N$ present in the wastewater. By optimizing the volume ratio of seawater draw solution/wastewater feed solution, a concentration factor of 3.1 and 3.7 was obtained for the FO and PRO modes, respectively. The results demonstrated the validity of the FO process for direct treatment of municipal wastewater by using seawater as the draw solution, while facilitating the subsequent utilization of concentrated wastewater for bioenergy production, which may have special implications for the coastline areas.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 가을 학술논문 발표대회
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• pp.179-180
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• 2020

In the budgeting guidelines, there are rules for calculating design fee and direct costs. However, only the design fee is calculated excluding the direct cost, which causes the cost to be insufficient. Therefore, this study is designed to analyze representative cases where direct costs are insufficient, draw out problems, and propose a way to improve design fees.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국내학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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• pp.82-85
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• 1988

This paper are the manufacture of controller of direct drive arm robot using 32 bit CPU(MC 69020). The work would draw on KIT of Robotics Laboratory whose extensive experience in 16 bit CPU Controller(MC 68008) in addition to the WHILE languages. We found that this controller is good for the direct drive arm robot controller for the use of self-tuning algorithms and real time control.

• 한국게임학회 논문지
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• 제1권1호
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• pp.68-72
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• 2001

DirectX Graphics plays the role of hardware independent 3 dimensional drawing interface for 3 dimensional video display. However the APIs in DirectX Graphics provide not only small improvement in velocity in the lowest level but also unstable performance of velocity according to their usages. In this paper, we present the structure of 3D game engine of efficient performance and describe functions and implementational features of game engines for an efficient 3D rendering in the environment of DirecX Graphics.

• 지식경영연구
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• 제16권4호
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• pp.69-87
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• 2015

Given the huge number of data produced by its users, SNS is a great source of customer insights. Since viral trends in SNS reflect customers' direct feedback, companies can draw out highly meaningful business insights when such data is effectively analyzed and managed. However, while the importance of understanding SNS big data keeps growing, the methods for analyzing atypical data such as SNS postings for business insights over product has not been well studied. This study aims to demonstrate the way to exploit topic modeling method to support marketing strategy generation and therefore leverage business process. First, we conducted topic modeling analysis for twitter data of Apple and Samsung smartphones. Then we comparatively examined the analysis results to draw meaningful market insights about each smartphone product. Finally, we draw out a strategic marketing recommendation for each smartphone brand based on the findings.

• 한국콘텐츠학회논문지
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• 제5권1호
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• pp.217-227
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• 2005

본 논문은 성능이 우수한 DirectX 기반 다채널 영상 감시 시스템을 설계 구현하고, 성능 분석한 결과를 제시한다. 본 논문의 시스템은 크게 디스플레이 서브시스템, 저장 서브시스템, 검색 및 재생 서브시스템으로 구성된다. 디스플레이 서브시스템은 빠른 디스플레이, 채널 간 디스플레이 동기 및 tearing effect 개선을 위해, DirectDraw의 H/W 가속 기능과 overlay, flip 기능을 효율적으로 이용하여 설계되었다. 저장 서브시스템은 저장 속도 개선을 위해, DirectShow 필터 기반 다중 쓰레드 구조로 설계되어 캡쳐 장치에서 획득되는 다채널의 영상 스트림이 채널별로 압축 저장되고 채널 간 데이터 병목 현상이 최소화되도록 하였다. 검색 및 재생 서브시스템에는 효율적인 인덱스 파일 구조와 영상 데이터 저장 구조, 재생 시에 채널별 동시 재생이 가능하도록 한 효율적인 재생 구조를 설계 구현하여 보다 빠른 재생 및 검색이 가능하도록 하였다. 실험결과, 제안된 시스템이 기존 시스템보다 저장 속도는 최고 2배 까지, 검색 및 재생 속도는 최고 3.5배 정도까지 개선되었음이 확인되었다.

• Structural Engineering and Mechanics
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• 제54권4호
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• pp.793-807
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• 2015

Constructing the influence lines of forces of statically indeterminate structures is a traditional issue in structural engineering and mechanics. However, the existing kinematic method for establishing these force influence lines is an indirect or mixed approach by combining the force method with the theorem of reciprocal displacements, which is yet inconsistent with the kinematic method for statically determinate structure. This paper proposes the direct kinematic method in conjunction with the load-displacement differential relation for exactly constructing influence lines of reaction and internal forces of indeterminate structures. Firstly, through applying the principle of virtual displacement, the formula for influence lines of reaction and internal forces of indeterminate structure via direct kinematic method is derived based on the released structure. Then, a computational approach with a clear concept and unified procedure as well as wide applicability based on the load-displacement differential relation of beam is suggested to achieve conveniently the closed-form expression of force influence lines, and exactly draw them. Finally, three representative examples for constructing force influence lines of statically indeterminate beams and frame illustrate the superiority of the proposed method.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (B)
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• pp.437-439
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• 2003

자연의 진화 과정을 모방한 유전자 알고리즘을 이미지 생성기 분야에 적응하여 무한히 다양한 이미지를 생성하는 것은 가능한 반면, 다음 세대에 생성될 이미지들의 예측은 난해하다. 이러한 배경 하에 본 논문에서는 대화식 프랙탈 이미지 생성기를 구현하여, Direct draw mode를 통해 프랙탈 이미지를 생성하기 위해 사용되는 아핀들을 사용자가 직접 변환함으로써 미세 조정이 가능하도록 한다.

• 응용통계연구
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• 제23권6호
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• pp.1245-1253
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• 2010

There are two main approaches for estimating the discontinuous regression function nonparametrically. One is the direct approach, the other is the indirect approach. The major goal of the two approaches are different. The direct approach focuses on the overall good estimation of the regression function itself, whereas the indirect approach focuses on the good estimation of jump locations. Apparently, the two approaches are quite different in nature. Gijbels et al. (2007) argue that the comparison of two approaches does not make much sense and that it is even difficult to choose an appropriate criterion for comparisons. However, it is obvious that the indirect approach also has the regression curve estimate as the subsidiary result. Therefore it is necessary to verify the appropriateness of the indirect approach as the estimator of the discontinuous regression function itself. Park (2009a) compared the performance of two approaches through a simulation study. In this paper, we consider a more general case and draw some useful conclusions.

• Asian Journal of Innovation and Policy
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• 제7권1호
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• pp.131-149
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• 2018

Multinational corporations (MNCs) leverage global locations for efficient production and sustained growth, and move significant foreign direct investments globally, particularly into emerging economies. MNCs also engage in entrepreneurial ecosystems of host countries for strategic benefits and impact the ecosystem as well. Of late, MNCs are increasingly entering into emerging economies like India through foreign direct investment (FDI) inflows and they are playing a vital role in start-up promotion in the entrepreneurial ecosystem. Therefore, we examine the role of MNCs and its impact on the entrepreneurial ecosystems in India by exploring a symbiotic relationship between MNCs and startups. We use a case-based method to ascertain and analyze specific benefits that emerge from such symbiotic relationships and draw implications for startups in India's technology entrepreneurial ecosystem.