• Title/Summary/Keyword: Key Object

Search Result 518, Processing Time 0.025 seconds

Analysis and monitoring on jacking construction of continuous box girder bridge

  • Li, Fangyuan;Wu, Peifeng;Yan, Xinfei
    • Computers and Concrete
    • /
    • v.16 no.1
    • /
    • pp.49-65
    • /
    • 2015
  • It is hard to guarantee the strict synchronization of all the jacking-up points in the integral jacking of a large-span continuous box girder bridge. This paper took the Hengliaojing Bridge as background, which need jacking up as an object with 295m length and more than 10,000tons weight, adopted 3D software to calculate the unsynchronized jacking-up working conditions, and studied the relationships between the unsynchronized vertical difference and the girder's deformation behaviour. The aim is to verify the maximum value of the unsynchronized vertical difference, and guide the construction and ensure safety. The monitoring system with its contents is introduced corresponding to the analysis. The results of the deck relative elevations prove that it is difficult to avoid the deck torsional deformation for jacking different; especially the side span shows more deformations for its smaller stiffness. The maximum difference is smaller than the limited value with acceptable stresses in the sections. The jacking heights of the pier in each construction step are controlled regularly according to the design. The shifting of the whole bridge in longitudinal direction is smaller than in transverse direction. The several beginning steps are the key to adjust their support reactions. This study is one parts of the fundamental research for the code "Technical specification for bridge jacking-up and reposition of China". The whole synchronous jacking project of the main bridge set a world record by the World Record Association for the whole bridge jacking project with the longest span of the world.

A BIM-based model for constructability assessment of conceptual design

  • Fadoul, Abdelaziz;Tizani, Walid;Koch, Christian
    • Advances in Computational Design
    • /
    • v.3 no.4
    • /
    • pp.367-384
    • /
    • 2018
  • The consideration of constructability issues at the design stage can lead to improved construction performance with smooth project delivery and savings in time and money. Empirical studies demonstrate the value obtained by integrating construction knowledge with the building design process, and its benefits for owners, contractors and designers. However, it is still a challenge to implement the concept into current design practice. There is a need for a decision support tool to aid designers in reviewing their design constructability, deploying current technological tools, such as BIM. Such tools are beneficial at the conceptual design stage when there is a room to improve the design significantly with less incurred cost. This research investigates how current process- and object-oriented models can be used to assess design constructability. It proposes a BIM-based model using embedded information within the design environment to conduct the assessment. The modelling framework is demonstrated in four key parts; namely, the conceptual design model, the constructability assessment model, the assessment process model and the decision-making phase. Each is associated with a set of components and functions that contribute towards the targeted constructability assessment outcomes. The proposed framework is the first to combine a numerical assessment system and a rule-based system, allowing for both quantitative and qualitative approaches. The modelling framework and its implementation through a prototype are described in this paper. It is believed that this framework is the first to enable users to transfer their construction knowledge and experience directly into a design platform linked to BIM models. The assessment criteria can be customised by the users who can reflect their own constructability preferences into various specialised profiles that can be added to the constructability assessment model. It also allows for the integration of the assessment process with the design phase, facilitating the optimisation of constructability performance from the early design stage.

Measurement of the intrinsic speed of sound in a hot melt ceramic slurry for 3D rapid prototyping with inkjet technology (3차원 잉크젯 쾌속 조형법을 위한 세라믹 상변화 잉크의 음속측정)

  • Shin, Dong-Youn
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.9 no.4
    • /
    • pp.892-898
    • /
    • 2008
  • 3D rapid prototyping is the manufacturing technology to fabricate a prototype with the data stored in a computer, which differs from conventional casting technology in terms of an additive process. Various 3D rapid prototyping techniques such as stereolithograpy. fused deposition modeling. selective laser sintering, laminated object manufacturing have been developed but among them, 3D inkjet printing has a unique feature that materials could be jetted to directly form the body of a prototype, which could be a finished product functionally and structurally. However, this needs ink with a high solid content, which tends to increase the dynamic viscosity of ink. The increase of ink viscositytends to restrict the jettable range of ink and hence the jetting conditions should be optimized. The intrinsic speed of sound in a hot melt ink with ceramic nanoparticles dispersed is one of key components to determine the jettable range of ink. In this paper, the way to measure the intrinsic speed of sound in a hot melt ceramic ink is proposed and its influence on the jetting condition is discussed.

Language Network Analysis of 'Marine Environment' in News Frame (언론의 '해양환경'에 대한 의제설정 언어 네트워크 분석)

  • Kim, Ho-Kyung;Kwon, Ki-Seok;Jang, Duckhee
    • The Journal of the Korea Contents Association
    • /
    • v.16 no.5
    • /
    • pp.385-398
    • /
    • 2016
  • This research analyzed domestic newspapers' agenda setting trend and meaning construction process on the issue of marine environment by year. The research conducted a language network analysis and used R program and Netminer program to analyze four major daily newspapers' news coverages (Dong-A, Joongang, Hanhyoreh, and Kyunghyang) for the last ten years (2005-2014). The results show that the issue of marine environment in Korean media reports are signified in the economic context. For the last ten years, news reports are mainly focused on the 'development' issue of marine environment, without distinction of year. The core key words of the networks are "development", "plan", and "project." However, diverse strategies for 'preservation' are not covered in media reports as a major issue. The importance of effective preservation and reasonable development should be considered in a balanced way. Korean media coverages mainly concentrate on the development issue, and it has a strong influence on considering the marine environment area as an object of development. Future direction and implication of the press reports related to marine environment are discussed.

FPGA Design of a SURF-based Feature Extractor (SURF 알고리즘 기반 특징점 추출기의 FPGA 설계)

  • Ryu, Jae-Kyung;Lee, Su-Hyun;Jeong, Yong-Jin
    • Journal of Korea Multimedia Society
    • /
    • v.14 no.3
    • /
    • pp.368-377
    • /
    • 2011
  • This paper explains the hardware structure of SURF(Speeded Up Robust Feature) based feature point extractor and its FPGA verification result. SURF algorithm produces novel scale- and rotation-invariant feature point and descriptor which can be used for object recognition, creation of panorama image, 3D Image restoration. But the feature point extraction processing takes approximately 7,200msec for VGA-resolution in embedded environment using ARM11(667Mhz) processor and 128Mbytes DDR memory, hence its real-time operation is not guaranteed. We analyzed integral image memory access pattern which is a key component of SURF algorithm to reduce memory access and memory usage to operate in c real-time. We assure feature extraction that using a Vertex-5 FPGA gives 60frame/sec of VGA image at 100Mhz.

Development of Infrastructure automatic alert populating system in Geotechincal Monitoring field (지반 분야에서의 시설물 안전위험 자동화 상황전파 시스템 개발)

  • Jung, Jea-Hyen;Kim, Yong-Su;Han, Sang-Jea
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2010.03a
    • /
    • pp.933-939
    • /
    • 2010
  • Gathering information and systemization of infrastructure disaster management is to reduce uncertainties in making decisions and maximize the number of alternations for reasonable decision making. The key object is the progress report & propagation automation system based on sensors, which is major for providing objective data to realize and support decision makings and delivering decision to a certain area, department, manager and other people rapidly. Collecting, reviewing and database of existing progress report & propagation manual in order to achieve networking of safety management on major social infrastructure of the nation, materialization of field-oriented intelligent business process by developing mobile safety management command transmission device and integrating it into facility safety management network.

  • PDF

The Relations Between The 6th Graders' Negative Cognitive Process.Anger Experience.Aggressiveness (초등학교 6학년의 부정적 인지과정.분노 경험.공격성 간의 관계)

  • Kim, Kyoung-Sook
    • The Korean Journal of Elementary Counseling
    • /
    • v.5 no.1
    • /
    • pp.205-226
    • /
    • 2006
  • The purpose of this study was to find out the relations between 6th graders' negative cognitive process and anger experience and aggressiveness. To achieve the goal, it conducted a test to examine children's negative cognitive process, anger experience, aggressiveness targeting 100 children of 6th grade in C elementary school, Gyeonggj province. Then it conducted SPSS 12.0 statistical program to get the results of correlation analysis and regression analysis. The outcomes were as follows. First, there was a meaningfully positive relation between a negative cognitive process and anger experience. In other words, children having more negative cognitive process seemed to experience the feelings of anger more often, this presented the important role of cognition while getting into a temper Second, it reported a positive relation between anger experience and aggressiveness. Children who have experienced anger more often showed more violent behaviors, especially there were more significant positive relations between trait-anger and aggressiveness compared to state-anger and aggressiveness. This could explain some possibilities that children with high level of trait-anger might outrage more often than others by recognizing the situations as anger stimulants. Third, when conducting a regression analysis, a negative cognitive process made an effect on anger experience which affected aggressiveness. However, it did not show a negative cognitive process making a direct effect on aggressiveness. This is considered that children could experience an anger while evaluating an event or object in a negative way based on individual belief, and emotional linguistic behavioral aggressiveness would be formalized as they express the sparked fury either internally or externally. In conclusion, this study proved that there were close relations between children's negative cognitive process and anger experience and aggressiveness. A negative cognitive process affects anger experience, and anger experience affects aggressiveness afterwards. A negative cognitive process affects aggressiveness through anger experience indirectly, and especially trait-anger among anger experience is the main factor to influence on aggressiveness. With consideration of these results, it is believed that mediation is important key to moderate the negative cognition and trait-anger in order to diminish children's aggressive behaviors. This study has a meaning to provide searching for manifold mediating methods between negative cognition and trait anger, with a fundamental resource.

  • PDF

History Management Technology of Building Construction and Maintenance Using Vector Photo Information and BIM (벡터사진 정보와 BIM을 활용한 건축물의 시공·유지관리 이력관리기술)

  • Kim, Kyoon-Tai;Lim, Myung-Gu;Kim, Gu-Taek
    • Journal of the Korea Institute of Building Construction
    • /
    • v.14 no.6
    • /
    • pp.605-613
    • /
    • 2014
  • Recently proposed intelligent images are generating, storing and managing along with existing image information and 5W1H information. Therefore, these vector images can be useful in searching and managing photos taking during building construction and maintenance processes. In addition, when the vector photos, a key to the intelligent image, is linked with BIM, it is possible to find BIM objects by utilizing information included in vector photos. And if the taken vector photo is saved as attributes of the extracted object, the vector photo can be managed as the historical data. Furthermore, this new technology will contribute to make the management of construction information more efficiently. This study is about the development of the technology of extracting BIM objects from vector photo information and managing the attributes of the extracted objects. Also the prototype modules was developed and tested to evaluate the processes of setting reference points, converting coordinate system, calculating positions, and so on. Through these processes, it was confirmed that the possibility of extracting BIM objects from vector photos and of managing attribute data of objects.

Attribute-Based Signatures with DNF Policies (DNF 정책을 가지는 속성 기반 서명)

  • Lee, Kwang-Su;Hwang, Jung-Yeon;Kim, Hyoung-Joong;Lee, Dong-Hoon
    • Journal of the Institute of Electronics Engineers of Korea CI
    • /
    • v.46 no.1
    • /
    • pp.78-87
    • /
    • 2009
  • An attribute-based signature scheme is a signature scheme where a signer's private key is associate with an attribute set and a signature is associated with an access structure. Attribute-based signature schemes are useful to provide anonymity and access control for role-based systems and attribute-based systems where an identity of object is represented as a set of roles or attributes. In this paper, we formally define the definition of attribute-based signature schemes and propose the first efficient attribute-based signature scheme that requires constant number of pairing operations for verification where a policy is represented as a disjunctive normal form (DNF). To construct provably secure one, we introduce a new interactive assumption and prove that our construction is secure under the new interactive assumption and the random oracle model.

Estimation of User Activity States for Context-Aware Computing in Mobile Devices (모바일 디바이스에서 상황인식 컴퓨팅을 위한 사용자 활동 상태 추정)

  • Baek Jonghun;Yun Byoung-Ju
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.43 no.1 s.307
    • /
    • pp.67-74
    • /
    • 2006
  • Contort-aware computing technology is one of the key technology of ubiquitous computing in the mobile device environment. Context recognition computing enables computer applications that automatically respond to user's everyday activity to be realized. In this paper, We use accelerometer could sense activity states of the object and apply to mobile devices. This method for estimating human motion states utilizes various statistics of accelerometer data, such as mean, standard variation, and skewness, as features for classification, and is expected to be more effective than other existing methods that rely on only a few simple statistics. Classification algorithm uses simple decision tree instead of existing neural network by considering mobile devices with limited resources. A series of experiments for testing the effectiveness of the our context detection system for mobile applications and ubiquitous computing has been performed, and its result is presented.