• Title/Summary/Keyword: local/global weight

Search Result 74, Processing Time 0.025 seconds

Per-deuteration and NMR experiments for the backbone assignment of 62 kDa protein, Hsp31

  • Kim, Jihong;Choi, Dongwook;Park, Chankyu;Ryu, Kyoung-Seok
    • Journal of the Korean Magnetic Resonance Society
    • /
    • v.19 no.3
    • /
    • pp.112-118
    • /
    • 2015
  • Hsp31 protein is one of the members of DJ-1 superfamily proteins and has a dimeric structure of which molecular weight (MW) is 62 kDa. The mutation of DJ-1 is closely related to early onset of Parkinson's disease. Hsp31 displays $Zn^{+2}$-binding activity and was first reported to be a holding chaperone in E. coli. Its additional glyoxalase III active has recently been characterized. Moreover, an incubation at $60^{\circ}C$ induces Hsp31 protein to form a high MW oligomer (HMW) in vitro, which accomplishes an elevated holding chaperone activity. The NMR technique is elegant method to probe any local or global structural change of a protein in responses to environmental stresses (heat, pH, and metal). Although the presence of the backbone chemical shifts (bbCSs) is a prerequisite for detailed NMR analyses of the structural changes, general HSQC-based triple resonance experiments could not be used for 62 kDa Hsp31 protein. Here, we prepared the per-deuterated Hsp31 and performed the TROSY-based triple resonance experiments for the bbCSs assignment. Here, detailed processes of per-deuteration and the NMR experiments are described for other similar NMR approaches.

Improved DV-Hop Localization Algorithm Based on Bat Algorithm in Wireless Sensor Networks

  • Liu, Yuan;Chen, Junjie;Xu, Zhenfeng
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.11 no.1
    • /
    • pp.215-236
    • /
    • 2017
  • Obtaining accurate location information is important in practical applications of wireless sensor networks (WSNs). The distance vector hop (DV-Hop) is a frequently-used range-free localization algorithm in WSNs, but it has low localization accuracy. Moreover, despite various improvements to DV-Hop-based localization algorithms, maintaining a balance between high localization accuracy and good stability and convergence is still a challenge. To overcome these shortcomings, we proposed an improved DV-Hop localization algorithm based on the bat algorithm (IBDV-Hop) for WSNs. The IBDV-Hop algorithm incorporates optimization methods that enhance the accuracy of the average hop distance and fitness function. We also introduce a nonlinear dynamic inertial weight strategy to extend the global search scope and increase the local search accuracy. Moreover, we develop an updated solutions strategy that avoids premature convergence by the IBDV-Hop algorithm. Both theoretical analysis and simulation results show that the IBDV-Hop algorithm achieves higher localization accuracy than the original DV-Hop algorithm and other improved algorithms. The IBDV-Hop algorithm also exhibits good stability, search capability and convergence, and it requires little additional time complexity and energy consumption.

Optimization of Sandwich Structures of a Small Aircraft Wing using Automated Aero- Structure Interaction Systems (자동화된 공력-구조 연계 시스템을 이용한 소형항공기 날개 샌드위치구조 최적설계)

  • Park, Chan Woo;Chu, Jae Myeong;Shul, Chang Won;Jun, Seung Moon
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.30 no.10
    • /
    • pp.1061-1068
    • /
    • 2013
  • In this research, the design optimization of a composite sandwich has been performed for using as an airplane wing skin. Automated analysis framework for aero-structure interaction is used for calculating load data on the wing. For automated analysis framework, FLUENT is used for computational fluid dynamics (CFD) analysis. CFD mesh is generated automatically by using parametric modeling of CATIA and GAMBIT. A computational structure mechanics (CSM) mesh is generated automatically by the parametric method of the CATIA and visual basic script of NASTRAN-FX. The structure is analyzed by ABAQUS. Composite sandwich optimization is performed by NASTRAN SOL200. Design variables are thicknesses of the sandwich core and composite skin panel plies. The objective is to minimize the weight of the wing and constraints are applied for wing tip displacement, global failure index and local failure indexes.

Hybrid Control Strategy for Autonomous Driving System using HD Map Information (정밀 도로지도 정보를 활용한 자율주행 하이브리드 제어 전략)

  • Yu, Dongyeon;Kim, Donggyu;Choi, Hoseung;Hwang, Sung-Ho
    • Journal of Drive and Control
    • /
    • v.17 no.4
    • /
    • pp.80-86
    • /
    • 2020
  • Autonomous driving is one of the most important new technologies of our time; it has benefits in terms of safety, the environment, and economic issues. Path following algorithms, such as automated lane keeping systems (ALKSs), are key level 3 or higher functions of autonomous driving. Pure-Pursuit and Stanley controllers are widely used because of their good path tracking performance and simplicity. However, with the Pure-Pursuit controller, corner cutting behavior occurs on curved roads, and the Stanley controller has a risk of divergence depending on the response of the steering system. In this study, we use the advantages of each controller to propose a hybrid control strategy that can be stably applied to complex driving environments. The weight of each controller is determined from the global and local curvature indexes calculated from HD map information and the current driving speed. Our experimental results demonstrate the ability of the hybrid controller, which had a cross-track error of under 0.1 m in a virtual environment that simulates K-City, with complex driving environments such as urban areas, community roads, and high-speed driving roads.

An Iterative Spot Matching for 2-Dimensional Protein Separation Images (반복 점진적 방법에 의한 2차원 단백질 분리 영상의 반점 정합)

  • Kim, Jung-Ja;Hoang, Minh T.;Kim, Dong-Wook;Kim, Nam-Gyun;Won, Yong-Gwan
    • Journal of Biomedical Engineering Research
    • /
    • v.28 no.5
    • /
    • pp.601-608
    • /
    • 2007
  • 2 Dimensional Gel Electrophoresis(2DGE) is an essentialmethodology for analysis on the expression of various proteins. For example, information for the location, mass, expression, size and shape of the proteins obtained by 2DGE can be used for diagnosis, prognosis and biological progress by comparison of patients with the normal persons. Protein spot matching for this purpose is comparative analysis of protein expression pattern for the 2DGE images generated under different conditions. However, visual analysis of protein spots which are more than several hundreds included in a 2DGE image requires long time and heavy effort. Furthermore, geometrical distortion makes the spot matching for the same protein harder. In this paper, an iterative algorithm is introduced for more efficient spot matching. Proposed method is first performing global matching step, which reduces the geometrical difference between the landmarks and the spot to be matched. Thus, movement for a spot is defined by a weighted sum of the movement of the landmark spots. Weight for the summation is defined by the inverse of the distance from the spots to the landmarks. This movement is iteratively performed until the total sum of the difference between the corresponding landmarks is larger than a pre-selected value. Due to local distortion generally occurred in 2DGE images, there are many regions in whichmany spot pairs are miss-matched. In the second stage, the same spot matching algorithm is applied to such local regions with the additional landmarks for those regions. In other words, the same method is applied with the expanded landmark set to which additional landmarks are added. Our proposed algorithm for spot matching empirically proved reliable analysis of protein separation image by producing higher accuracy.

Buckling Test and Non-linear Analysis of Aluminium Isogrid Panel (알루미늄 lsogrid 패널의 좌굴시험 및 비선형 해석)

  • Yoo, Joon-Tae;Lee, Jong-Woong;Yoon, Jong-Hoon;Jang, Young-Soon;Yi, Yeong-Moo;Cho, Gwang-Rae
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.33 no.4
    • /
    • pp.35-40
    • /
    • 2005
  • There are many methods to reinforce the cylindrical structure for light weight design like skin-stringer and semi-monocoque. Isogrid is one of the reinforced structures to improve buckling load. Isogrid has many advantages for complex load case, internal pressure and concentrated load.In this paper, compressive buckling test and non-linear FE analysis of the isogrid panel are described. Diameter of panel is 2.4m and thickness of plate is 11.43mm. The angle which the panel accomplish is about 70 degrees and, its height is about 660mm. Local buckling, global buckling and variation of stiffness after local buckling were observed during buckling test of the panel. MSC/MARC is used for non-linear FE analysis. When analysis, initial imperfection of panel which occurred during plastic forming is considered. The results of analysis for buckling mode and buckling load have good agreements with test.

Question Similarity Measurement of Chinese Crop Diseases and Insect Pests Based on Mixed Information Extraction

  • Zhou, Han;Guo, Xuchao;Liu, Chengqi;Tang, Zhan;Lu, Shuhan;Li, Lin
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.15 no.11
    • /
    • pp.3991-4010
    • /
    • 2021
  • The Question Similarity Measurement of Chinese Crop Diseases and Insect Pests (QSM-CCD&IP) aims to judge the user's tendency to ask questions regarding input problems. The measurement is the basis of the Agricultural Knowledge Question and Answering (Q & A) system, information retrieval, and other tasks. However, the corpus and measurement methods available in this field have some deficiencies. In addition, error propagation may occur when the word boundary features and local context information are ignored when the general method embeds sentences. Hence, these factors make the task challenging. To solve the above problems and tackle the Question Similarity Measurement task in this work, a corpus on Chinese crop diseases and insect pests(CCDIP), which contains 13 categories, was established. Then, taking the CCDIP as the research object, this study proposes a Chinese agricultural text similarity matching model, namely, the AgrCQS. This model is based on mixed information extraction. Specifically, the hybrid embedding layer can enrich character information and improve the recognition ability of the model on the word boundary. The multi-scale local information can be extracted by multi-core convolutional neural network based on multi-weight (MM-CNN). The self-attention mechanism can enhance the fusion ability of the model on global information. In this research, the performance of the AgrCQS on the CCDIP is verified, and three benchmark datasets, namely, AFQMC, LCQMC, and BQ, are used. The accuracy rates are 93.92%, 74.42%, 86.35%, and 83.05%, respectively, which are higher than that of baseline systems without using any external knowledge. Additionally, the proposed method module can be extracted separately and applied to other models, thus providing reference for related research.

Impact response of a novel flat steel-concrete-corrugated steel panel

  • Lu, Jingyi;Wang, Yonghui;Zhai, Ximei;Zhou, Hongyuan
    • Steel and Composite Structures
    • /
    • v.42 no.2
    • /
    • pp.277-288
    • /
    • 2022
  • A novel flat steel plate-concrete-corrugated steel plate (FS-C-CS) sandwich panel was proposed for resisting impact load. The failure mode, impact force and displacement response of the FS-C-CS panel under impact loading were studied via drop-weight impact tests. The combined global flexure and local indentation deformation mode of the FS-C-CS panel was observed, and three stages of impact process were identified. Moreover, the effects of corrugated plate height and steel plate thickness on the impact responses of the FS-C-CS panels were quantitatively analysed, and the impact resistant performance of the FS-C-CS panel was found to be generally improved on increasing corrugated plate height and thickness in terms of smaller deformation as well as larger impact force and post-peak mean force. The Finite Element (FE) model of the FS-C-CS panel under impact loading was established to predict its dynamic response and further reveal its failure mode and impact energy dissipation mechanism. The numerical results indicated that the concrete core and corrugated steel plate dissipated the majority of impact energy. In addition, employing end plates and high strength bolts as shear connectors could prevent the slip between steel plates and concrete core and assure the full composite action of the FS-C-CS panel.

The Dynamic Relationship between Stock Returns and Investors' Behavior : Trading Hour and Non-trading Hour Analysis (주가와 투자 주체의 상호 관계에 관한 연구 : 거래 시간대와 비거래 시간대 수익률 분석)

  • Ko, Kwang-Soo;Kim, Kwang-Ho
    • The Korean Journal of Financial Management
    • /
    • v.27 no.2
    • /
    • pp.145-167
    • /
    • 2010
  • We investigate the dynamic relationship between stock returns and investors' behavior. For the putpose of the paper, daily KOSPI returns are decomposed into two parts: overnight returns and daytime returns. Overnight return is measured by the closing price of the previous day and the opening price of the current day. And daytime return is measured by the opening and closing prices of the current day. Qvernight returns are assumed to reflect global economic information, and daytime returns, domestic or local information. Major results are as follows: Foreign investors' behavior has an effect on the overnight returns more than the daytime returns. Individual investors' behavior, however, has little effect on the overnight returns, but not the daytime returns. Consequently, forecast error variance decomposition shows that the variance explanation power of foreign investors is higher in overnight returns rather than in the daytime returns. And the variance explanation power of individual investors is higher in daytime returns rather than in overnight returns. It implies that foreign investors employ dynamic hedging strategies and give more weight to global economic information rather than to domestic information. We conclude that investment behavior of foreign investors and domestic individuals is based on different economic information. This paper's findings are consistent with the economic situation that the Korean capital markets have faced since the global financial crisis of August 2008.

  • PDF

Image Quality Enhancement for Chest X-ray images (흉부 엑스레이 영상을 위한 화질 개선 알고리즘)

  • Park, So Yeon;Song, Byung Cheol
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.52 no.10
    • /
    • pp.97-107
    • /
    • 2015
  • The initial X-ray images obtained from a digital X-ray machine have a wide data range and uneven brightness level than normal images. In particular, in Chest X-ray images, it is necessary to improve naturally all of the parts such as ribs, spine, tissue, etc. These X-ray images can not be improved enough from conventional image quality enhancement algorithms because their characteristics are different from ordinary images'. This paper proposes to eliminate unnecessary background from an input image and expand the histogram range of the image. Then, we adjust the weight per frequency band of the image for improvement of contrast and sharpness. Finally, jointly taking the advantages of global contrast enhancement and local contrast enhancement methods we obtain an improved X-ray image suitable for effective diagnosis in comparison with the existing methods. Experimental results show quantitatively that the proposed algorithm provides better X-ray images in terms of the discrete entropy and saturation than the previous works.