• Molecules and Cells
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• 제27권3호
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• pp.271-277
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• 2009

Proteins interact with each other within a cell, and those interactions give rise to the biological function and dynamical behavior of cellular systems. Generally, the protein interactions are temporal, spatial, or condition dependent in a specific cell, where only a small part of interactions usually take place under certain conditions. Recently, although a large amount of protein interaction data have been collected by high-throughput technologies, the interactions are recorded or summarized under various or different conditions and therefore cannot be directly used to identify signaling pathways or active networks, which are believed to work in specific cells under specific conditions. However, protein interactions activated under specific conditions may give hints to the biological process underlying corresponding phenotypes. In particular, responsive functional modules consist of protein interactions activated under specific conditions can provide insight into the mechanism underlying biological systems, e.g. protein interaction subnetworks found for certain diseases rather than normal conditions may help to discover potential biomarkers. From computational viewpoint, identifying responsive functional modules can be formulated as an optimization problem. Therefore, efficient computational methods for extracting responsive functional modules are strongly demanded due to the NP-hard nature of such a combinatorial problem. In this review, we first report recent advances in development of computational methods for extracting responsive functional modules or active pathways from protein interaction network and microarray data. Then from computational aspect, we discuss remaining obstacles and perspectives for this attractive and challenging topic in the area of systems biology.

• 한국콘텐츠학회논문지
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• 제8권1호
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• pp.259-271
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• 2008

본 논문에서는 단백질-단백질 상호작용과 도메인 분석을 통해 기능이 알려지지 않은 미지 단백질의 기능을 예측할 수 있는 알고리즘을 제안한다. 먼저 MIPS 데이터베이스로부터 효모에 대한 단백질-단백질 상호작용(PPI) 네트러크를 구축한다. 구축된 PPI 네트워크는(단백질 3,637개, 상호작용 10,391개) 많은 상호작용을 갖는 소수의 단백질들을 갖으면서 단백질 클러스터의 고유한 모듈성을 보이는 스케일 프리 네트워크와 계층적 네트워크의 특성을 보인다 단백질-단백질 상호작용 데이터베이스는 Y2보(Yeast Two Hybrid) 실험 등으로 얻어졌기 때문에 부정확한 데이터를 포함하고 있다. 따라서 본 논문에서는 세포상의 localization을 고려하여 부정확한 데이터를 정제하여 PPI 네트워크를 재구축한다. 그리고 허브 단백질과 네트워크 구조를 분석하여 네트워크로부터 구조적 모듈을 발견하고 이를 정의한다. 또한 이러한 구조적 모듈로부터 단백질의 도메인을 분석하여 기능적 모듈을 밝히고, 높은 확실성을 가지는 기능적 모듈을 기반으로 미지 단백질에 대한 기능을 예측한다.

• Smart Structures and Systems
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• 제32권3호
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• pp.135-151
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• 2023

Using 3D asphalt pavement surface data, a deep and multiscale network named CrackNet-M is proposed in this paper for pixel-level crack detection for improvements in both accuracy and robustness. The CrackNet-M consists of four function-specific architectural modules: a central branch net (CBN), a crack map enhancement (CME) module, three pooling feature pyramids (PFP), and an output layer. The CBN maintains crack boundaries using no pooling reductions throughout all convolutional layers. The CME applies a pooling layer to enhance potential thin cracks for better continuity, consuming no data loss and attenuation when working jointly with CBN. The PFP modules implement direct down-sampling and pyramidal up-sampling with multiscale contexts specifically for the detection of thick cracks and exclusion of non-crack patterns. Finally, the output layer is optimized with a skip layer supervision technique proposed to further improve the network performance. Compared with traditional supervisions, the skip layer supervision brings about not only significant performance gains with respect to both accuracy and robustness but a faster convergence rate. CrackNet-M was trained on a total of 2,500 pixel-wise annotated 3D pavement images and finely scaled with another 200 images with full considerations on accuracy and efficiency. CrackNet-M can potentially achieve crack detection in real-time with a processing speed of 40 ms/image. The experimental results on 500 testing images demonstrate that CrackNet-M can effectively detect both thick and thin cracks from various pavement surfaces with a high level of Precision (94.28%), Recall (93.89%), and F-measure (94.04%). In addition, the proposed CrackNet-M compares favorably to other well-developed networks with respect to the detection of thin cracks as well as the removal of shoulder drop-offs.

• Advances in robotics research
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• 제1권1호
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• pp.101-126
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• 2014

In this article we present modular neural control for a leg-wheel hybrid robot consisting of three legs with omnidirectional wheels. This neural control has four main modules having their functional origin in biological neural systems. A minimal recurrent control (MRC) module is for sensory signal processing and state memorization. Its outputs drive two front wheels while the rear wheel is controlled through a velocity regulating network (VRN) module. In parallel, a neural oscillator network module serves as a central pattern generator (CPG) controls leg movements for sidestepping. Stepping directions are achieved by a phase switching network (PSN) module. The combination of these modules generates various locomotion patterns and a reactive obstacle avoidance behavior. The behavior is driven by sensor inputs, to which additional neural preprocessing networks are applied. The complete neural circuitry is developed and tested using a physics simulation environment. This study verifies that the neural modules can serve a general purpose regardless of the robot's specific embodiment. We also believe that our neural modules can be important components for locomotion generation in other complex robotic systems or they can serve as useful modules for other module-based neural control applications.

• Molecules and Cells
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• 제45권5호
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• pp.317-328
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• 2022

Trophoblasts, important functional cells in the placenta, play a critical role in maintaining placental function. The heterogeneity of trophoblasts has been reported, but little is known about the trophoblast subtypes and distinctive functions during preeclampsia (PE). In this study, we aimed to gain insight into the cell type-specific transcriptomic changes by performing unbiased single-cell RNA sequencing (scRNA-seq) of placental tissue samples, including those of patients diagnosed with PE and matched healthy controls. A total of 29,006 cells were identified in 11 cell types, including trophoblasts and immune cells, and the functions of the trophoblast subtypes in the PE group and the control group were also analyzed. As an important trophoblast subtype, extravillous trophoblasts (EVTs) were further divided into 4 subgroups, and their functions were preliminarily analyzed. We found that some biological processes related to pregnancy, hormone secretion and immunity changed in the PE group. We also identified and analyzed the regulatory network of transcription factors (TFs) identified in the EVTs, among which 3 modules were decreased in the PE group. Then, through in vitro cell experiments, we found that in one of the modules, CEBPB and GTF2B may be involved in EVT dysfunction in PE. In conclusion, our study showed the different transcriptional profiles and regulatory modules in trophoblasts between placentas in the control and PE groups at the single-cell level; these changes may be involved in the pathological process of PE, providing a new molecular theoretical basis for preeclamptic trophoblast dysfunction.

• 한국정밀공학회지
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• 제20권1호
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• pp.229-239
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• 2003

The design process of machine tools is regarded as a sequential, discrete, and inefficient works as it requires various kinds of design tools and many working hours. This paper describes an integrated design system embedding a design methodology that can support efficiently and systematically the conceptual structural design of machine tools. The system is a knowledge-based design system and has four machine-tool-specific functional modules including configuration design, configuration analysis, structure design, and structural analysis support module. Through the configuration design and analysis module, a machine configuration appropriate for design requirements is selected, and then the arrangement of ribs fer each structural part is decided in the structure design module. Also, the structural analysis support module is used to evaluate design result by utilizing structural analysis software, ANSYS. The system is applied to design of a tapping machine, and shows that the machine structure can be designed fast and conveniently by processing each design step interactively.

• 전자공학회논문지A
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• 제32A권10호
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• pp.81-92
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• 1995

In this paper, we present a high-level synthesis system that generates area-efficient RT-level datapaths with multiport memories. The proposed scheduling algorithm assigns an operation to a specific control step such that maximal sharing of functional units can be achieved with minimal number of memory ports, while satisfying given constraints. We propose a measure of multiport memory cost, MAV (Multiple Access Variable) which is defined as a variable accessed at several control steps , and overall memory cost is reduced by equally distributing the MAVs throughout all the control steps. Experimental results show the effectiveness of the proposed algorithm. When compared with previous approaches for several benchmarks available from literature, the proposed algorithm generates the datapaths with less memory modules and interconnection structures by reflecting the memory cost in the scheduling process.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제16권10호
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• pp.980-984
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• 2010

microRNA (miRNA)와 mRNA 조절 상호작용 탐색은 다양한 생물학적 현상에 있어 새로운 시야를 제공해 줄 수 있다. 최근 생물학적 프로세스에서 miRNA는 유전자 발현을 제어하고 세포를 기능적으로 조절하는 중요한 역할을 하는 요소로 밝혀졌다. 이에 복잡한 생물학 시스템에서 miRNA의 기능적 활동을 이해하기 위해서는 miRNA와 mRNA간 상호작용 분석은 필수적이다. 그러나 아직까지 복잡한 miRNA와 mRNA간 상호작용 관계를 추론하는 것은 어려운 문제이기 때문에 많은 연구자들이 실험적, 전산학적 접근 방법을 제안하며 활발한 연구를 진행하고 있다. 본 논문에서는 이종의 발현 데이터로부터 기능적으로 상호작용하는 miRNA-mRNA 조합을 탐색하기 위한 진화 연산 기반의 새로운 하이퍼네트워크 모델을 제안한다. 이에 실험결과로 제안하는 방법을 인간 암 관련 miRNA와 mRNA 발현 데이터에 적용하여 암 특이적 miRNA-mRNA 상호작용 집합을 탐색하고 발견한 miRNA-mRNA 상호작용 관계가 생물학적으로 유의함을 제시한다.

• 신재생에너지
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• 제9권2호
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• pp.30-39
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• 2013

Multi-crystalline silicon solar cells is not exist a specific crystal direction different from single crystalline silicon solar cells. In functional materials, therefore, isotropic wet etching of mc-Si solar cell is easy the acid solution rather than the alkaline solution. The reflectance of wet texturing process is about 25% and the reflectance of RIE texturing process is achieved less than 10%. In addition, wet texturing has many disadvantages as well as reflectance. So wet texturing process has been replaced by a RIE texturing process. In order to apply BIPV, RIE and wet textured multi-crystalline silicon solar cell modules was manufactured by different kind of EVA sheet. Moreover, in case of BIPV, the short circuit current characteristics according to the angle of incidence is more important, because the installation of BIPV is fixed location. In this study, we has measured SEM image and I-V curve of RIE and wet textured silicon solar cell and PV module. Also we has analyzed quantum efficiency characteristics of RIE and wet textured silicon solar cell for PV modules depending on incidence angle.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권6호
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• pp.2963-2978
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• 2017

The Top-K query is currently played a key role in a wide range of road network, decision making and quantitative financial research. In this paper, a Top-K recommendation algorithm is proposed to solve the cold-start problem and a tag generating method is put forward to enhance the semantic understanding of the OLAP session. In addition, a recommendation system for OLAP sessions called "OLAP4R" is designed using collaborative filtering technique aiming at guiding the user to find the ultimate goals by interactive queries. OLAP4R utilizes a mixed system architecture consisting of multiple functional modules, which have a high extension capability to support additional functions. This system structure allows the user to configure multi-dimensional hierarchies and desirable measures to analyze the specific requirement and gives recommendations with forthright responses. Experimental results show that our method has raised 20% recall of the recommendations comparing the traditional collaborative filtering and a visualization tag of the recommended sessions will be provided with modified changes for the user to understand.