A dynamic strain prediction method for malfunction of sensors in buildings subjected to seismic loads using CWT and CNN.

Structural health monitoring (SHM) is a technique used to evaluate the safety of a structure based on the structural response. In the SHM, sensors may fail to measure the structural response, or data loss can occur during the data transmission and reception. In this regard, this paper proposes a method of predicting the strain response when a sensor installed in a structural member suffers a malfunction.

Towards environmental sustainability in the local community: Future insights for managing the hazardous pollutants at construction sites.

Although various technologies are being developed in the construction industry, management technologies for achieving environmental sustainability in the local community are still lacking. As such, this study suggests future insights for the development of an automated intelligent environment management system for the promotion of environmental sustainability in the local community, through a systematic review of 1,707 relevant literature. The systematic review was conducted in two steps: (i) quantitative review: keyword co-occurrence and trend analysis; and (ii) qualitative review: a review on monitoring, evaluation, and improvement technologies.

Development of a real-time automated monitoring system for managing the hazardous environmental pollutants at the construction site.

The management of noise, vibration, and dust, which are hazardous pollutants from construction sites, is essential to minimize the health damage of the nearby residents and the economic damage of construction companies due to pollutants from construction sites. For the effective management of hazardous pollutants, their emissions from construction sites must be identified immediately and accurately. Therefore, this study developed a real-time automated monitoring system named "MOnitoring for Noise, Vibration, and Dust (MONVID)" for comprehensively measuring the hazardous environmental pollutants and managing them in real-time.

Multi-objective green design model to mitigate environmental impact of construction of mega columns for super-tall buildings.

The mega columns used in super-tall buildings are several meters in size; thus, a greater quantity of construction materials are required than for a general column. Considering the environmental impact, research on a green design model for super-tall buildings is necessary. This design model should minimize both CO emissions and cost in the mega-column construction and design phases with consideration of the member or building size.

Checklist of the tidal pool fishes of Jeju Island, Korea.

Seventy-six species of fishes, representing 60 genera and 34 families, were recorded from tidal pools on Jeju Island, southern Korea. The major families in terms of species were the Gobiidae (11 species), Pomacentridae (8 species), Blenniidae (6 species), and Labridae (5 species). Thirty-nine species were classified as tropical, 26 as temperate and 11 as subtropical.

Maximum stress estimation model for multi-span waler beams with deflections at the supports using average strains.

The safety of a multi-span waler beam subjected simultaneously to a distributed load and deflections at its supports can be secured by limiting the maximum stress of the beam to a specific value to prevent the beam from reaching a limit state for failure or collapse. Despite the fact that the vast majority of accidents on construction sites occur at waler beams in retaining wall systems, no safety monitoring model that can consider deflections at the supports of the beam is available. In this paper, a maximum stress estimation model for a waler beam based on average strains measured from vibrating wire strain gauges (VWSGs), the most frequently used sensors in construction field, is presented.

Magnetic nanoclusters engineered by polymer-controlled self-assembly for the accurate diagnosis of atherosclerotic plaques via magnetic resonance imaging.

Oleyl dextran-coated magnetic nanoclusters (ODMCs) are fabricated for the accurate detection of macrophage-rich atherosclerotic plaques using magnetic resonance (MR) imaging. Dextran is introduced to the cluster surface of magnetic nanocrystals (MNCs) through self-assembly using amphiphilic oleic acid-conjugated dextran (ODex) to provide not only hydrophilicity but also a high affinity to macrophages. Enhanced magnetism of the ODMCs is engineered by optimizing the degree of substitution (DS) of the oleyl group in ODex and the concentration of ODex used for the synthesis of ODMC.

Framework for the mapping of the monthly average daily solar radiation using an advanced case-based reasoning and a geostatistical technique.

For the effective photovoltaic (PV) system, it is necessary to accurately determine the monthly average daily solar radiation (MADSR) and to develop an accurate MADSR map, which can simplify the decision-making process for selecting the suitable location of the PV system installation. Therefore, this study aimed to develop a framework for the mapping of the MADSR using an advanced case-based reasoning (CBR) and a geostatistical technique. The proposed framework consists of the following procedures: (i) the geographic scope for the mapping of the MADSR is set, and the measured MADSR and meteorological data in the geographic scope are collected; (ii) using the collected data, the advanced CBR model is developed; (iii) using the advanced CBR model, the MADSR at unmeasured locations is estimated; and (iv) by applying the measured and estimated MADSR data to the geographic information system, the MADSR map is developed.

A practical monitoring system for the structural safety of mega-trusses using wireless vibrating wire strain gauges.

Sensor technologies have been actively employed in structural health monitoring (SHM) to evaluate structural safety. To provide stable and real-time monitoring, a practical wireless sensor network system (WSNS) based on vibrating wire strain gauges (VWSGs) is proposed and applied to a building under construction. In this WSNS, the data measured from each VWSG are transmitted to the sensor node via a signal line and then transmitted to the master node through a short-range wireless communication module (operating on the Industrial, Scientific, and Medical (ISM) band).

A wireless MEMS-based inclinometer sensor node for structural health monitoring.

This paper proposes a wireless inclinometer sensor node for structural health monitoring (SHM) that can be applied to civil engineering and building structures subjected to various loadings. The inclinometer used in this study employs a method for calculating the tilt based on the difference between the static acceleration and the acceleration due to gravity, using a micro-electro-mechanical system (MEMS)-based accelerometer. A wireless sensor node was developed through which tilt measurement data are wirelessly transmitted to a monitoring server.

Field monitoring of column shortenings in a high-rise building during construction.

The automatic monitoring of shortenings of vertical members in high-rise buildings under construction is a challenging issue in the high-rise building construction field. In this study, a practical system for monitoring column shortening in a high-rise building under construction is presented. The proposed monitoring system comprises the following components: (1) a wireless sensing system and (2) the corresponding monitoring software.

Evaluation of stiffness changes in a high-rise building by measurements of lateral displacements using GPS technology.

The outrigger truss system is one of the most frequently used lateral load resisting structural systems. However, little research has been reported on the effect of installation of outrigger trusses on improvement of lateral stiffness of a high-rise building through full-scale measurements. In this paper, stiffness changes of a high-rise building due to installation of outrigger trusses have been evaluated by measuring lateral displacements using a global positioning system (GPS).

A wireless laser displacement sensor node for structural health monitoring.

This study describes a wireless laser displacement sensor node that measures displacement as a representative damage index for structural health monitoring (SHM). The proposed measurement system consists of a laser displacement sensor (LDS) and a customized wireless sensor node. Wireless communication is enabled by a sensor node that consists of a sensor module, a code division multiple access (CDMA) communication module, a processor, and a power module.

A new position measurement system using a motion-capture camera for wind tunnel tests.

Considering the characteristics of wind tunnel tests, a position measurement system that can minimize the effects on the flow of simulated wind must be established. In this study, a motion-capture camera was used to measure the displacement responses of structures in a wind tunnel test, and the applicability of the system was tested. A motion-capture system (MCS) could output 3D coordinates using two-dimensional image coordinates obtained from the camera.

A practical data recovery technique for long-term strain monitoring of mega columns during construction.

A practical data recovery method is proposed for the strain data lost during the safety monitoring of mega columns. The analytical relations among the measured strains are derived to recover the data lost due to unexpected errors in long-term measurement during construction. The proposed technique is applied to recovery of axial strain data of a mega column in an irregular building structure during construction.

A strain-based load identification model for beams in building structures.

A strain-based load identification model for beam structures subjected to multiple loads is presented. The number of sensors for the load identification model is the same as the number of load conditions acting on a beam structure. In the model, the contribution of each load to the strains measured by strain sensors is defined.

Symbolic and graphical representation scheme for sensors deployed in large-scale structures.

As wireless sensor network (WSN)-based structural health monitoring (SHM) systems are increasingly being employed in civil infrastructures and building structures, the management of large numbers of sensing devices and the large amount of data acquired from WSNs will become increasingly difficult unless systematic expressions of the sensor network are provided. This study introduces a practical WSN for SHM that consists of sensors, wireless sensor nodes, repeater nodes, master nodes, and monitoring servers. This study also proposes a symbolic and graphical representation scheme (SGRS) for this system, in which the communication relationships and respective location information of the distributed sensing components are expressed in a concise manner.

An integrative structural health monitoring system for the local/global responses of a large-scale irregular building under construction.

In this study, a practical and integrative SHM system was developed and applied to a large-scale irregular building under construction, where many challenging issues exist. In the proposed sensor network, customized energy-efficient wireless sensing units (sensor nodes, repeater nodes, and master nodes) were employed and comprehensive communications from the sensor node to the remote monitoring server were conducted through wireless communications. The long-term (13-month) monitoring results recorded from a large number of sensors (75 vibrating wire strain gauges, 10 inclinometers, and three laser displacement sensors) indicated that the construction event exhibiting the largest influence on structural behavior was the removal of bents that were temporarily installed to support the free end of the cantilevered members during their construction.

A deformed shape monitoring model for building structures based on a 2D laser scanner.

High-rise buildings subjected to lateral loads such as wind and earthquake loads must be checked not to exceed the limits on the maximum lateral displacement or the maximum inter-story drift ratios. In this paper, a sensing model for deformed shapes of a building structure in motion is presented. The deformed shape sensing model based on a 2D scanner consists of five modules: (1) module for acquiring coordinate information of a point in a building; (2) module for coordinate transformation and data arrangement for generation of time history of the point; (3) module for smoothing by adjacent averaging technique; (4) module for generation of the displacement history for each story and deformed shape of a building, and (5) module for evaluation of the serviceability of a building.

Wireless laser range finder system for vertical displacement monitoring of mega-trusses during construction.

As buildings become increasingly complex, construction monitoring using various sensors is urgently needed for both more systematic and accurate safety management and high-quality productivity in construction. In this study, a monitoring system that is composed of a laser displacement sensor (LDS) and a wireless sensor node was proposed and applied to an irregular building under construction. The subject building consists of large cross-sectional members, such as mega-columns, mega-trusses, and edge truss, which secured the large spaces.

Estimation of the monthly average daily solar radiation using geographic information system and advanced case-based reasoning.

The photovoltaic (PV) system is considered an unlimited source of clean energy, whose amount of electricity generation changes according to the monthly average daily solar radiation (MADSR). It is revealed that the MADSR distribution in South Korea has very diverse patterns due to the country's climatic and geographical characteristics. This study aimed to develop a MADSR estimation model for the location without the measured MADSR data, using an advanced case based reasoning (CBR) model, which is a hybrid methodology combining CBR with artificial neural network, multiregression analysis, and genetic algorithm.

Efficient CD44-targeted magnetic resonance imaging (MRI) of breast cancer cells using hyaluronic acid (HA)-modified MnFe2O4 nanocrystals.

Targeted molecular imaging with hyaluronic acid (HA) has been highlighted in the diagnosis and treatment of CD44-overexpressing cancer. CD44, a receptor for HA, is closely related to the growth of cancer including proliferation, metastasis, invasion, and angiogenesis. For the efficient detection of CD44, we fabricated a few kinds of HA-modified MnFe2O4 nanocrystals (MNCs) to serve as specific magnetic resonance (MR) contrast agents (HA-MRCAs) and compared physicochemical properties, biocompatibility, and the CD44 targeting efficiency.

Design and application of a field sensing system for ground anchors in slopes.

In a ground anchor system, cables or tendons connected to a bearing plate are used for stabilization of slopes. Then, the stability of a slope is dependent on maintaining the tension levels in the cables. So far, no research on a strain-based field sensing system for ground anchors has been reported.

Double-ligand modulation for engineering magnetic nanoclusters.

Magnetic nanoclusters (MNCs) are agglomerated individual magnetic nanoparticles (MNPs) that show great promise in increasing magnetic resonance imaging (MRI) sensitivity. Here, we report an effective strategy to engineer MNCs based on double-ligand modulation to enhance MRI sensitivity. The oleic acid-coated individual MNPs self-assembled and then were enveloped by polysorbate 80, using a nanoemulsion method to prepare MNCs.