• Title/Summary/Keyword: Technical measurements

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Camber calculation of prestressed concrete I-Girder considering geometric nonlinearity

  • Atmaca, Barbaros;Ates, Sevket
    • Computers and Concrete
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    • v.19 no.1
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    • pp.1-6
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    • 2017
  • Prestressed concrete I-girders are subject to different load types at their construction stages. At the time of strand release, i.e., detensioning, prestressed concrete girders are under the effect of dead and prestressing loads. At this stage, the camber, total net upward deflection, of prestressed girder is summation of the upward deflection due to the prestressing force and the downward deflection due to dead loads. For the calculation of the upward deflection, it is generally considered that prestressed concrete I-girder behaves linear-elastic. However, the field measurements on total net upward deflection of prestressed I-girder after detensioning show contradictory results. In this paper, camber calculations with the linear-elastic beam and elastic-stability theories are presented. One of a typical precast I-girder with 120 cm height and 31.5 m effective span length is selected as a case study. 3D finite element model (FEM) of the girder is developed by SAP2000 software, and the deflections of girder are obtained from linear and nonlinear-static analyses. Only geometric nonlinearity is taken into account. The material test and field measurement of this study are performed at prestressing girder plant. The results of the linear-elastic beam and elastic-stability theories are compared with FEM results and field measurements. It is seen that the camber predicted by elastic-stability theory gives acceptable results than the linear-elastic beam theory while strand releasing.

X-RAY FLUORESCENCE IN RESEARCH ON THE CULTURAL HERITAGE

  • Cechak, Tomas;Kopecka, Ivana;Musilek, Ladislav
    • Journal of Radiation Protection and Research
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    • v.26 no.3
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    • pp.321-326
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    • 2001
  • Radionuclide X-ray fluorescence analysis is a method, which has many advantages for analysing various historic artefacts, as it is relatively cheap, sensitive and non-destructive, and it allows measurements in-situ. However, this analysis has also certain limitations especially concerning sensitivity to chemical elements only, irrespective of the compounds or chemical forms in which these elements have been bonded. In addition, light elements emitting very soft X-rays cannot be measured, and in order to detect a wide range of elements, it is necessary to carry out repeated measurements with different radiation sources. Despite these limitations, valuable information can be obtained about the composition of historic materials and data about the origin and age of these artefacts can be derived. Analyses of wall paintings, ancient metal sculptures or other objects of art provide the basis for historic considerations documented in our results for some objects belonging to the Czech cultural heritage. The results are promising. Thus it is expected that our laboratory will expand its work into more fields of the fine and applied arts.

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Characteristics of Brown Sauce Made with Various Amount of Chungkukjang Powder (청국장 가루를 첨가한 브라운 소스의 품질 특성)

  • Lim, Kyung-Ryo;Kim, Ki-Young;Choi, Soo-Keun;Kim, Yong-Sik;Lee, Kyung-Hee
    • Journal of the East Asian Society of Dietary Life
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    • v.20 no.2
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    • pp.263-271
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    • 2010
  • The study examined the quality characteristics of brown sauce made with various amounts (2%, 4%, 6%, 8% and 10%) of Chungkukjang powder. Sensory tests and measurements of viscosity, moistness, and color done and the antioxidant effects of Chungkukjang powder in brown sauce were examined by measurements of acid, peroxide, TBA during 12 days storage at $24^{\circ}C$. Overall sensory preference was highest in brown sauce made with 6% Chungkukjang powder. As the powder content increased the Lightness, Redness and Yellowness values decreased as did viscosity. Acid, peroxide and full term for TBA values increased to a low level that produced an edible product even at 12 days.

On low cost model-based monitoring of industrial robotic arms using standard machine vision

  • Karagiannidisa, Aris;Vosniakos, George C.
    • Advances in robotics research
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    • v.1 no.1
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    • pp.81-99
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    • 2014
  • This paper contributes towards the development of a computer vision system for telemonitoring of industrial articulated robotic arms. The system aims to provide precision real time measurements of the joint angles by employing low cost cameras and visual markers on the body of the robot. To achieve this, a mathematical model that connects image features and joint angles was developed covering rotation of a single joint whose axis is parallel to the visual projection plane. The feature that is examined during image processing is the varying area of given circular target placed on the body of the robot, as registered by the camera during rotation of the arm. In order to distinguish between rotation directions four targets were used placed every $90^{\circ}$ and observed by two cameras at suitable angular distances. The results were deemed acceptable considering camera cost and lighting conditions of the workspace. A computational error analysis explored how deviations from the ideal camera positions affect the measurements and led to appropriate correction. The method is deemed to be extensible to multiple joint motion of a known kinematic chain.

The development of a field measurement instrumentation system for low-rise construction

  • Porterfield, Michelle L.;Jones, Nicholas P.
    • Wind and Structures
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    • v.4 no.3
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    • pp.247-260
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    • 2001
  • In the last three decades several comprehensive field measurement programs have produced significant insight into the wind effects on low-rise structures. The most notable and well published of these efforts are measurements being collected at the Wind Engineering Field Laboratory (WERFL) at Texas Tech University, measurements on low-rise structures in Silsoe, England and measurements on groups of low-rise structures collected in Aylesbury, England. Complementary to these efforts, an additional full-scale field investigation program has recently collected meteorological, pressure, strain and displacement data on a low-rise structure in Southern Shores, North Carolina. To date over seventy-five hundred data sets have been collected at the Southern Shores site in a variety meteorological conditions up to and including hurricane-force winds. This paper provides details of the system, its development, and preliminary assessment of its performance. A description of the field site, the instrumented structure, and the instrumentation system is provided. In addition, an example of the data collected during three hurricanes is presented. The primary goal of this paper is to provide the reader with the necessary technical details to appropriately interpret data from this experiment, which will be presented in future publications currently under development.

Study on Sleeve Patterns of Men's Jackets from 17C to 19C (17세기$\sim$19세기 남성 재킷류의 소매패턴 연구)

  • Park, Sang-Hee;Choi, Jeong-Wook
    • Journal of the Korea Fashion and Costume Design Association
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    • v.10 no.2
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    • pp.105-115
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    • 2008
  • Men's outer wear, such as jackets and coats appeared since the 16th century. They have been changed from doublets, coats, justaucorps, tail-coats, frock coats and morning coats to contemporary men's suits. Since the early 17th century, sleeve patterns of men's outer jackets had been mostly two-pieces close fitted patterns. The purpose of this article is to compare sleeve patterns of various jackets, which appear in various historic costume books. Armhole measurements, sleeve head measurements, amounts of ease, armhole depths, armhole widths, crown heights, sleeve width and sleeve angle had been compared to find out the differences among patterns of different times and styles. Coming to the present, the difference between top sleeve and under sleeve became more obvious, and the sleeve angle became less curvy. Another interesting point is that there had been considerable amounts of ease, which is the difference between sleeve head measurements and corresponding armhole measurements. It is because the sleeve has been attached to the armhole not by seam but by string. It is believed that the present sleeves have more natural curve and shape compared to the past.

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The Role of High-throughput Transcriptome Analysis in Metabolic Engineering

  • Jewett, Michael C.;Oliveira, Ana Paula;Patil, Kiran Raosaheb;Nielsen, Jens
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.5
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    • pp.385-399
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    • 2005
  • The phenotypic response of a cell results from a well orchestrated web of complex interactions which propagate from the genetic architecture through the metabolic flux network. To rationally design cell factories which carry out specific functional objectives by controlling this hierarchical system is a challenge. Transcriptome analysis, the most mature high-throughput measurement technology, has been readily applied In strain improvement programs in an attempt to Identify genes involved in expressing a given phenotype. Unfortunately, while differentially expressed genes may provide targets for metabolic engineering, phenotypic responses are often not directly linked to transcriptional patterns, This limits the application of genome-wide transcriptional analysis for the design of cell factories. However, improved tools for integrating transcriptional data with other high-throughput measurements and known biological interactions are emerging. These tools hold significant promise for providing the framework to comprehensively dissect the regulatory mechanisms that identify the cellular control mechanisms and lead to more effective strategies to rewire the cellular control elements for metabolic engineering.

Photocatalytic degradation of textile dye CI Basic Yellow 28 wastewater by Degussa P25 based TiO2

  • Konecoglu, Gulhan;Safak, Toygun;Kalpakli, Yasemen;Akgun, Mesut
    • Advances in environmental research
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    • v.4 no.1
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    • pp.25-38
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    • 2015
  • Wastewaters of textile industry cause high volume colour and harmful substance pollutions. Photocatalytic degradation is a method which gives opportunity of reduction of organic pollutants such as dye containing wastewaters. In this study, photocatalytic degradation of C.I. Basic Yellow 28 (BY28) as a model dye contaminant was carried out using Degussa P25 in a photocatalytic reactor. The experiments were followed out at three different azo dye concentrations in a reactor equipped UV-A lamp (365 nm) as a light source. Azo dye removal efficiencies were examined with total organic carbon and UV-vis measurements. As a result of experiments, maximum degradation efficiency was obtained as 100% at BY28 concentration of $50mgL^{-1}$ for the reaction time of 2.5 h. The photodegradation of BY28 was described by a pseudo-first-order kinetic model modified with the langmuir-Hinshelwood mechanism. The adsorption equilibrium constant and the rate constant of the surface reaction were calculated as $K_{dye}=6.689{\cdot}10^{-2}L\;mg^{-1}$ and $k_c=0.599mg\;L^{-1}min^{-1}$, respectively.

Development and application of Smart Water Cities global standards and certification schemes based on Key Performance Indicators

  • Lea Dasallas;Jung Hwan Lee;Su Hyung Jang
    • Proceedings of the Korea Water Resources Association Conference
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    • 2023.05a
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    • pp.183-183
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    • 2023
  • Smart water cities (SWC) are urban municipalities that utilizes modern innovations in managing and preserving the urban water cycle in the city; with the purpose of securing sustainability and improving the quality of life of the urban population. Understanding the different urban water characteristics and management strategies of cities situate a baseline in the development of evaluation scheme in determining whether the city is smart and sustainable. This research herein aims to develop measurements and evaluation for SWC Key Performance Indicators (KPIs), and set up a unified global standard and certification scheme. The assessment for SWC is performed in technical, as well as governance and prospective aspects. KPI measurements under Technical Pillar assess the cities' use of technologies in providing sufficient water supply, monitoring water quality, strengthening disaster resilience, minimizing hazard vulnerability, and maintaining and protecting the urban water ecosystem. Governance and Prospective Pillar on the other hand, evaluates the social, economic and administrative systems set in place to manage the water resources, delivering water services to different levels of society. The performance assessment is composed of a variety of procedures performed in a quantitative and qualitative manner, such as computations through established equations, interviews with authorities in charge, field survey inspections, etc. The developed SWC KPI measurements are used to evaluate the urban water management practices for Busan Eco Delta city, a Semulmeori waterfront area in Gangseo district, Busan. The evaluation and scoring process was presented and established, serving as the basis for the application of the smart water city certification all over the world. The established guideline will be used to analyze future cities, providing integrated and comprehensive information on the status of their urban water cycle, gathering new techniques and proposing solutions for smarter measures.

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Analytical and experimental modal analyses of a highway bridge model

  • Altunisik, Ahmet Can;Bayraktar, Alemdar;Sevim, Baris
    • Computers and Concrete
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    • v.12 no.6
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    • pp.803-818
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    • 2013
  • In this study, analytical and experimental modal analyses of a scaled bridge model are carried out to extract the dynamic characteristics such as natural frequency, mode shapes and damping ratios. For this purpose, a scaled bridge model is constructed in laboratory conditions. Three dimensional finite element model of the bridge is constituted and dynamic characteristics are determined, analytically. To identify the dynamic characteristics experimentally; Experimental Modal Analyses (ambient and forced vibration tests) are conducted to the bridge model. In the ambient vibration tests, natural excitations are provided and the response of the bridge model is measured. Sensitivity accelerometers are placed to collect signals from the measurements. The signals collected from the tests are processed by Operational Modal Analysis; and the dynamic characteristics of the bridge model are estimated using Enhanced Frequency Domain Decomposition and Stochastic Subspace Identification methods. In the forced vibration tests, excitation of the bridge model is induced by an impact hammer and the frequency response functions are obtained. From the finite element analyses, a total of 8 natural frequencies are attained between 28.33 and 313.5 Hz. Considering the first eight mode shapes, these modes can be classified into longitudinal, transverse and vertical modes. It is seen that the dynamic characteristics obtained from the ambient and forced vibration tests are close to each other. It can be stated that the both of Enhanced Frequency Domain Decomposition and Stochastic Subspace Identification methods are very useful to identify the dynamic characteristics of the bridge model. The first eight natural frequencies are obtained from experimental measurements between 25.00-299.5 Hz. In addition, the dynamic characteristics obtained from the finite element analyses have a good correlation with experimental frequencies and mode shapes. The MAC values obtained between 90-100% and 80-100% using experimental results and experimental-analytical results, respectively.