• Safety and Health at Work
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• v.9 no.4
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• pp.473-478
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• 2018

Background: Multiple Chemical Sensitivity (MCS) is an acquired disease which etiology remains unknown. It is characterized by the development of sensitivity to certain chemical products. Most of the hypotheses formulated to explain the syndrome associate it to a previous exposition to some kind of volatile chemical. University researchers in chemical laboratories suffer a phenomenon of multi-exposition to chemical agents at low concentration during long periods of time although in an irregular form. Many of these chemical agents have similar properties to those suspicious of causing MCS. This article studies the prevalence of MCS in laboratory researchers. Methods: The study group is university researchers in chemical laboratories. The control group was obtained from administrative personnel who work in the same universities and therefore, are not exposed to chemical products from the laboratories, but have the same exposition to the rest of environmental polluting agents from the area and from the buildings of the university. In this study, it is used the Quick Environmental Exposure and Sensitivity Inventory (QEESI) (sensitivity of 92%/specificity of 95%). Results: The results showed that the prevalence of MCS for the university researchers is not related to exposition by inhalation to multiple chemical agents, at low concentration. Conclusions: The results disagree with one of the main etiological hypotheses of MCS, which is based on the existence of hypersensitive people, who presents a response after prolonged expositions to very low concentrations during a long period of time.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.530-539
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• 2007

Many construction projects such as highways, pipelines, tunnels, and high-rise buildings typically contain repetitive activities. Research has shown that the Critical Path Method (CPM) is not efficient in scheduling linear construction projects that involve repetitive tasks. Linear Scheduling Method (LSM) is one of the techniques that have been developed since 1960s to handle projects with repetitive characteristics. Although LSM has been regarded as a technique that provides significant advantages over CPM in linear construction projects, it has been mainly viewed as a graphical complement to the CPM. Studies of scheduling linear construction projects with resource consideration are rare, especially with multiple resource constraints. The objective of this proposed research is to explore a resource assignment mechanism, which assigns multiple critical resources to all activities to minimize the project duration while satisfying the activities precedence relationship and resource limitations. Resources assigned to an activity are allowed to vary within a range at different stations, which is a combinatorial optimization problem in nature. A heuristic multiple resource allocation algorithm is explored to obtain a feasible initial solution. The Simulated Annealing search algorithm is then utilized to improve the initial solution for obtaining near-optimum solutions. A housing example is studied to demonstrate the resource assignment mechanism.

• Journal of information and communication convergence engineering
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• v.5 no.1
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• pp.78-82
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• 2007

This paper propose a building reconstruction method of urban area for a 3D GIS with stereo images. The 3D reconstruction is performed by the grouping 3D line segments extracted from the stereo matching of salient edges which are derived from multiple images. The grouping is achieved by conditions of degrees and distances between lines. Building objects are determined by the junction combinations of the grouped line segments. The proposed algorithm demonstrates effective results of 3D reconstruction of buildings with 2D aerial images.

• Smart Structures and Systems
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• v.23 no.3
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• pp.243-261
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• 2019

This paper introduces an appropriate technique to estimate the weighting matrices used in the linear quadratic regulator (LQR) method for active structural control. For this purpose, a parameter is defined to regulate the relationship between the structural energy and control force. The optimum value of the regulating parameter, is determined for single degree of freedom (SDOF) systems under seismic excitations. In addition, the suggested technique is generalized for multiple degrees of freedom (MDOF) active control systems. Numerical examples demonstrate the robustness of the proposed method for controlled buildings under a wide range of seismic excitations.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.367-371
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• 2005

Social noise survey on multiple residential noises such as nut impact, air-borne, bathroom, drainage and traffic noises was conducted to investigate major variables affecting the overall satisfaction for noise environment The effect of individual noise perception on the evaluation of the overall noise environment was investigated through a questionnaire survey on annoyance, disturbance and noise sensitivity. Auditory experiments was also undertaken to determine noise level according to the percent of satisfaction for individual noise source. As a result of survey, it was found that satisfaction for floor impact noise most greatly affects the overall satisfaction for noise environment and annoyance most greatly affects the satisfaction for individual noise sources. Result of auditory experiment showed that the noise level of floor impact noise by bang machine, airborne, drainage and traffic noise corresponding to 50% satisfaction is 44dB($L_{i,Fmax,AW}$) and 40dBA, respectively.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.225-226
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• 2014

In multi-story buildings, heavy-weight floor impact noise propagates through multiple layers. In order to evaluate the influence of structural vibration and propagation, the actual twelve-story building was excited by an impact ball. Sound and vibration responses of each floor was measured using accelerometers and a microphone. Vibration characteristics and its transfer paths were different depending on the excitation floor locations due to differences in the structural characteristics. From the measurement result, transfer characteristics were quantified by statistical energy analysis. It was confirmed that the heavy-weight floor impact noise influence not only adjacent floor. The impact noise transferred and affected multiple layers.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.673-679
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• 2009

Nondestructive inspection(NDI) is a testing procedure used to easily inspect an object for internal defects, abnormalities, shape, and structure, etc. without destroying it. Typical candidates for NDI include buildings, railways, aircraft, bridges, underground pipelines and various types of factory equipment. Recent advances in nondestructive evaluation(NDE) technologies have led to improved methods for quality control and in-service inspection, and the development of new options for material diagnostics. This paper introduces the methods of a survey and assessment on NDI applications in Electric Multiple Units(EMU). The main objective of this paper was to obtain information on various applications of NDI technology in EMU.

• International Journal of High-Rise Buildings
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• v.7 no.2
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• pp.161-170
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• 2018

Rapid urbanization, resource depletion, and limited land are further increasing the need for skyscrapers in city centers; therefore, it is imperative to enhance tall building performance efficiency and energy-generative capability. Potential performance improvements can be explored using parametric multi-objective optimization, aided by evaluation tools, such as computational fluid dynamics and energy analysis software, to visualize and explore skyscrapers' multi-resource, multi-system generative potential. An optimization-centered, software-based design platform can potentially enable the simultaneous exploration of multiple strategies for the decreased consumption and large-scale production of multiple resources. Resource Generative Skyscrapers (RGS) are proposed as a possible solution to further explore and optimize the generative potentials of skyscrapers. RGS can be optimized with waste-energy-harvesting capabilities by capitalizing on passive features of integrated renewable systems. This paper describes various resource-generation technologies suitable for a synergetic integration within the RGS typology, and the software tools that can facilitate exploration of their optimal use.

• Structural Engineering and Mechanics
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• v.14 no.1
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• pp.85-98
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• 2002

The use of supplemental damping to dissipate seismic energy is one of the most economical and effective ways to mitigate the effects of earthquakes on structures. Both displacement-dependent and velocity-dependent devices dissipate earthquake-induced energy effectively. Combining displacement-dependent and velocity-dependent devices for seismic mitigation of structures minimizes the shortcomings of individual dampers, and is the most economical solution for seismic mitigation. However, there are few publications related to the optimum distributions of combined devices in a multiple-bay frame building. In this paper, the effectiveness of a building consisting of multiple bags equipped with combined displacement-dependent and velocity-dependent devices is investigated. A four-story building with six bays was selected as an example to examine the efficiency of the proposed combination methods. The parametric study shows that appropriate arrangements of different kinds of devices make the devices more efficient and economical.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.121-123
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• 2011

The accuracy of GPS varies depending on the number of GPS satellites and is declined in GPS interfering spot such as around forest or buildings. This paper proposes a localization improvement algorithm in GPS interfering spot by integrating information of multiple sensors in smartphone. The proposed algorithm is implemented in smartphone and the performance is evaluated in campus area.