• 제목/요약/키워드: Fine Tuning

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Action Research: the Use of Enterprise Resource Planning System in Construction Engineering and Project Management

  • Chan, Eric W.L.
    • Journal of Construction Engineering and Project Management
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    • 제1권3호
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    • pp.18-27
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    • 2011
  • Although information communication technology (ICT) is long regard as very useful tool in today's construction engineering and project management environment, organizations must not only operate based upon its original setting, but also requires on-going observation, additional features and fine-tuning actions before the desirable outcome can be achieved. However, it is a very common phenomenon that organizations purchase the licensed "off-the-shelf-software" package and customize it to suit their own business need. Due to the incapability of such software and inefficient customization, the possible result is making that ICT tool not user-friendly and sometimes the whole system becomes obsolete. The purpose of this paper is to review and report those actions taken (between February 2006 and December 2010) by a construction organization to enhance the performance of its Enterprise Resource Planning (ERP) system launched in December 2002. Such actions include: improving data inputting method; removing the transition bottleneck; introducing crystallization function; revising the organization's "Delegation and Limits of Authority"; publishing the "League Table" amongst users; integrating the 3D Mode into the system and upgrading hardware. Whilst the ultimate goals of such system are well beyond the time limit of this research study, an obvious interim result, achieved by this case studied organization, was winning a landmark project worth US$500 million after the ERP system was functioned properly and effectively. Their experience and success becomes an exemplar which can be borrowed by those companies, from managerial perspectives and as a roadmap, planning to adopt information technology (IT) strategy and use ICT tool in the construction engineering and project management framework. Singapore, where public housing provisions have been a major concern of their citizens as the building stock gets older.

데이터 정보입자 기반 퍼지 추론 시스템의 최적화 (Optimization of Fuzzy Inference Systems Based on Data Information Granulation)

  • 오성권;박건준;이동윤
    • 대한전기학회논문지:시스템및제어부문D
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    • 제53권6호
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    • pp.415-424
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    • 2004
  • In this paper, we introduce and investigate a new category of rule-based fuzzy inference system based on Information Granulation(IG). The proposed rule-based fuzzy modeling implements system structure and parameter identification in the efficient form of “If..., then...” statements, and exploits the theory of system optimization and fuzzy implication rules. The form of the fuzzy rules comes with three types of fuzzy inferences: a simplified one that involves conclusions that are fixed numeric values, a linear one where the conclusion part is viewed as a linear function of inputs, and a regression polynomial one as the extended type of the linear one. By the nature of the rule-based fuzzy systems, these fuzzy models are geared toward capturing relationships between information granules. The form of the information granules themselves becomes an important design features of the fuzzy model. Information granulation with the aid of HCM(Hard C-Means) clustering algorithm hell)s determine the initial parameters of rule-based fuzzy model such as the initial apexes of the membership functions and the initial values of polynomial function being used in the Premise and consequence Part of the fuzzy rules. And then the initial Parameters are tuned (adjusted) effectively with the aid of the improved complex method(ICM) and the standard least square method(LSM). In the sequel, the ICM and LSM lead to fine-tuning of the parameters of premise membership functions and consequent polynomial functions in the rules of fuzzy model. An aggregate objective function with a weighting factor is proposed in order to achieve a balance between performance of the fuzzy model. Numerical examples are included to evaluate the performance of the proposed model. They are also contrasted with the performance of the fuzzy models existing in the literature.

탄소나노튜브 인솔 착용에 따른 드롭 착지 동작의 생체역학적 분석 (Biomechanical Analysis of Wearing Carbon Nanotube-Based Insole during Drop Landing)

  • 채원식;정재후;이행섭
    • 한국운동역학회지
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    • 제22권4호
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    • pp.429-435
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    • 2012
  • The purpose of this study was to determine the biomechanical effect of wearing carbon nanotube-based insole on cushioning and muscle tuning during drop landing. Twenty male university students(age: $21.2{\pm}1.5yrs$, height: $175.4{\pm}4.7cm$, weight: $70.2{\pm}5.8kg$) who have no musculoskeletal disorder were recruited as the subjects. Average axial strain, average shear strain, inversion angle, linear velocity, angular velocity, vertical GRF and loading rate were determined for each trial. For each dependent variable, a one-way analysis of variance(ANOVA) with repeated measures was performed to test if significant difference existed among different three conditions(p<.05). The results showed that Average axial strain of line 4 was significantly less in CNT compared with EVA and PU during IP phase. The average shear strain was less in CNT compared with EVA and PU during other phases. The inversion angle was increased in CNT compared with EVA and PU during all phase. In linear velocity, angular velocity, vertical GRF and loading rate, there were no significant difference between the three groups. This result seems that fine particle of carbon nanotube couldn't make geometric form which can absolve impact force by increasing density through eliminating voids of forms. Thus, searching for methods that keep voids of forms may play a pivotal role in developing of insole. This has led to suggestions of the need for further biomechanical analysis to these factors.

마우스 수컷 생식세포에서 비스페놀 A에 대한 인삼 에탄올 추출물의 보호 효과 (Protective Effect of Panax ginseng Ethanol Extracts Against Bisphenol A (BPA) in Mouse Male Germ Cells)

  • 김형돈;손상현;김진성;이희정;박춘근;안영섭;이상원;김영옥
    • 한국약용작물학회지
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    • 제23권2호
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    • pp.138-143
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    • 2015
  • This study was carried out to evaluate the preventive effect of three forms of Korean ginseng roots (fresh, white and red) against bisphenol A (BPA) toxicity in mouse male germ cells (GC-2spd, TM3, TM4). ROS (reactive oxygen species) generation were measured by DCF-DA (2',7'-dichlorohydrofluorescein diacetate) assay. Also, semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) was performed to quantify the mRNA expression levels of apoptosis-related genes, Bax (pro-apoptotic gene) and Bcl2 (anti-apoptotic gene). ROS generation was increased by $50{\mu}M$ BPA, but definitely decreased by treatment with Korean ginseng extracts (fresh, white and red) in mouse male germ cells. In especial, Korean fresh ginseng extract reduced significantly ROS production to normal control. In addition, Korean fresh and white ginseng extracts suppressed the apoptosis of mouse male germ cells by fine-tuning mRNA levels of apoptotic genes changed by BPA. In general, Korean fresh ginseng extract was more effective than white ginseng extract for reducing BPA-induced oxidative stress and apoptosis in mouse male germ cells. Therefore, Korean fresh and white ginseng may help to alleviate biphenol A toxicity in mouse male germ cells.

Atomic Layer Deposition for Energy Devices and Environmental Catalysts

  • Kim, Young Dok
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.77.2-77.2
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    • 2013
  • In this talk, I will briefly review recent results of my group related to application of atomic layer deposition (ALD) for fabricating environmental catalysts and organic solar cells. ALD was used for preparing thin films of TiO2 and NiO on mesporous silica with a mean pore size of 15 nm. Upon depositing TiO2 thin films of TiO2 using ALD, the mesoporous structure of the silica substrate was preserved to some extent. We show that efficiency for removing toluene by adsorption and catalytic oxidation is dependent of mean thickness of TiO2 deposited on silica, i.e., fine tuning of the thickness of thin film using ALD can be beneficial for preparing high-performing adsorbents and oxidation catalysts of volatile organic compound. NiO/silica system prepared by ALD was used for catalysts of chemical conversion of CO2. Here, NiO nanoparticles are well dispersed on silica and confiend in the pore, showing high catalytic activity and stability at 800oC for CO2 reforming of methane reaction. We also used ALD for surface modulation of buffer layers of organic solar cell. TiO2 and ZnO thin films were deposited on wet-chemically prepared ZnO ripple structures, and thin films with mean thickness of ~2 nm showed highest power conversion efficiency of organic solar cell. Moreover, performance of ALD-prepared organic solar cells were shown to be more stable than those without ALD. Thin films of oxides deposited on ZnO ripple buffer layer could heal defect sites of ZnO, which can act as recombination center of electrons and holes.

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교차로 공용차로 운영 효율성 분석 (A Study on the Operational Efficiency of Intersection Shared Lanes)

  • 박근영;이시복
    • 한국ITS학회 논문지
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    • 제14권1호
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    • pp.13-21
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    • 2015
  • 본 연구에서는 두 가지 형태의 공용차로 운영 효율성에 초점을 맞추어 분석을 수행하였다. 직진 우회전 공용차로의 경우 인접한 직진차로에 비해 이용률이 현저히 떨어지는 것으로 나타났으며 그로 인해 신호운영의 효율성이 떨어지는 것으로 분석되었다. 이를 개선하기 위해서는 우선 차로별 교통량 수집을 통한 보다 정교한 신호최적화가 필요하다 할 수 있으며, 나아가 운전자 교육, 홍보를 통해 공용차로의 이용률을 제고하여야 할 것이다. 좌회전 유턴 공용차로에서는 유턴 교통량에 대한 대향 우회전 교통량 비율에 따라 포화교통류율이 감소한다는 것을 확인할 수 있었다. 하지만 유턴, 우회전 차량간 간섭에 따른 현실적인 포화교통류율 보정치를 개발하기 위해서는 차량간 간섭이 일어날 가능성에 대한 확률모형의 정립이 필요한 것으로 판단된다.

Combinatorial Fine-Tuning of Phospholipase D Expression by Bacillus subtilis WB600 for the Production of Phosphatidylserine

  • Huang, Tingting;Lv, Xueqin;Li, Jianghua;Shin, Hyun-dong;Du, Guocheng;Liu, Long
    • Journal of Microbiology and Biotechnology
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    • 제28권12호
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    • pp.2046-2056
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    • 2018
  • Phospholipase D has great commercial value due to its transphosphatidylation products that can be used in the food and medicine industries. In order to construct a strain for use in the production of PLD, we employed a series of combinatorial strategies to increase PLD expression in Bacillus subtilis WB600. These strategies included screening of signal peptides, selection of different plasmids, and optimization of the sequences of the ribosome-binding site (RBS) and the spacer region. We found that using the signal peptide amyE results in the highest extracellular PLD activity (11.3 U/ml) and in a PLD expression level 5.27-fold higher than when the endogenous signal peptide is used. Furthermore, the strain harboring the recombinant expression plasmid pMA0911-PLD-amyE-his produced PLD with activity enhanced by 69.03% (19.1 U/ml). We then used the online tool \RBS Calculator v2.0 to optimize the sequences of the RBS and the spacer. Using the optimized sequences resulted in an increase in the enzyme activity by about 26.7% (24.2 U/ml). In addition, we found through a transfer experiment that the retention rate of the recombinant plasmid after 5 generations was still 100%. The final product, phosphatidylserine (PS), was successfully detected, with transphosphatidylation selectivity at 74.6%. This is similar to the values for the original producer.

Ventx1.1 competes with a transcriptional activator Xcad2 to regulate negatively its own expression

  • Kumar, Shiv;Umair, Zobia;Kumar, Vijay;Lee, Unjoo;Choi, Sun-Cheol;Kim, Jaebong
    • BMB Reports
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    • 제52권6호
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    • pp.403-408
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    • 2019
  • Dorsoventral patterning of body axis in vertebrate embryo is tightly controlled by a complex regulatory network of transcription factors. Ventx1.1 is known as a transcriptional repressor to inhibit dorsal mesoderm formation and neural differentiation in Xenopus. In an attempt to identify, using chromatin immunoprecipitation (ChIP)-Seq, genome-wide binding pattern of Ventx1.1 in Xenopus gastrulae, we observed that Ventx1.1 associates with its own 5'-flanking sequence. In this study, we present evidence that Ventx1.1 binds a cis-acting Ventx1.1 response element (VRE) in its own promoter, leading to repression of its own transcription. Site-directed mutagenesis of the VRE in the Ventx1.1 promoter significantly abrogated this inhibitory autoregulation of Ventx1.1 transcription. Notably, Ventx1.1 and Xcad2, an activator of Ventx1.1 transcription, competitively co-occupied the VRE in the Ventx1.1 promoter. In support of this, mutation of the VRE down-regulated basal and Xcad2-induced levels of Ventx1.1 promoter activity. In addition, overexpression of Ventx1.1 prevented Xcad2 from binding to the Ventx1.1 promoter, and vice versa. Taken together, these results suggest that Ventx1.1 negatively regulates its own transcription in competition with Xcad2, thereby fine-tuning its own expression levels during dorsoventral patterning of Xenopus early embryo.

딥러닝을 이용한 마스크 착용 여부 검사 시스템 (Mask Wearing Detection System using Deep Learning)

  • 남충현;남은정;장경식
    • 한국정보통신학회논문지
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    • 제25권1호
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    • pp.44-49
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    • 2021
  • 최근 COVID-19로 인해 마스크 착용 여부 자동 검사 시스템에 신경망 기술들을 적용하는 연구가 활발히 진행되고 있다. 신경망 적용 방식에 있어서 1단계 검출 방식 또는 2단계 검출 방식을 사용하며, 데이터를 충분히 확보할 수 없는 경우 사전 학습된 신경망에 대해 가중치 미세 조절 기법을 적용하여 학습한다. 본 논문에서는 얼굴 인식부와 마스크 검출부로 구성되는 2단계 검출 방식을 적용하였으며, 얼굴 인식부에는 MTCNN 모델, 마스크 검출부에는 ResNet 모델을 사용하였다. 마스크 검출부는 다양한 실 상황에서의 인식률과 추론 속도 향상을 위하여 5개의 ResNet모델을 적용하여 실험하였다. 학습 데이터는 웹 크롤러를 이용하여 수집한 17,219개의 정지 영상을 이용하였으며, 1,913개의 정지 영상과 1분 동영상 2개에 대해 각각 추론을 실시하였다. 실험 결과 정지 영상인 경우 96.39%, 동영상인 경우 92.98%의 높은 정확도를 보였고, 동영상 추론 속도는 10.78fps임을 확인하였다.

Elastic net 기반 특징 선택을 적용한 fNIRS 기반 뇌-컴퓨터 인터페이스 데이터셋 분류 정확도 평가 (Assessment of Classification Accuracy of fNIRS-Based Brain-computer Interface Dataset Employing Elastic Net-Based Feature Selection)

  • 신재영
    • 대한의용생체공학회:의공학회지
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    • 제42권6호
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    • pp.268-276
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    • 2021
  • Functional near-infrared spectroscopy-based brain-computer interface (fNIRS-based BCI) has been receiving much attention. However, we are practically constrained to obtain a lot of fNIRS data by inherent hemodynamic delay. For this reason, when employing machine learning techniques, a problem due to the high-dimensional feature vector may be encountered, such as deteriorated classification accuracy. In this study, we employ an elastic net-based feature selection which is one of the embedded methods and demonstrate the utility of which by analyzing the results. Using the fNIRS dataset obtained from 18 participants for classifying brain activation induced by mental arithmetic and idle state, we calculated classification accuracies after performing feature selection while changing the parameter α (weight of lasso vs. ridge regularization). Grand averages of classification accuracy are 80.0 ± 9.4%, 79.3 ± 9.6%, 79.0 ± 9.2%, 79.7 ± 10.1%, 77.6 ± 10.3%, 79.2 ± 8.9%, and 80.0 ± 7.8% for the various values of α = 0.001, 0.005, 0.01, 0.05, 0.1, 0.2, and 0.5, respectively, and are not statistically different from the grand average of classification accuracy estimated with all features (80.1 ± 9.5%). As a result, no difference in classification accuracy is revealed for all considered parameter α values. Especially for α = 0.5, we are able to achieve the statistically same level of classification accuracy with even 16.4% features of the total features. Since elastic net-based feature selection can be easily applied to other cases without complicated initialization and parameter fine-tuning, we can be looking forward to seeing that the elastic-based feature selection can be actively applied to fNIRS data.