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Purpose Routine screening for carotid intima-media thickness (CIMT) and cardiovascular (CV) disease in asymptomatic patients has been criticized for the high costs and large number of patients required for detecting one patient with coronary artery disease (CAD). In order to overcome the low cost-effectiveness thereof, we investigated the feasibility of an economic wireless handheld ultrasound (WHUS) device for CIMT measurement in symptomatic patients. Materials and methods A total of 100 consecutive patients with cardiac symptoms were enrolled. CIMT was measured in all patients. Coronary angiography was performed in 75 patients indicated for the exam. Results The mean of maximal CIMT measured from left/right common carotid artery and bulb (max-CIMT) by the WHUS device showed excellent agreement [intraclass correlation coefficient (ICC)=0.960] with a standard ultrasound device and great interobserver repeatability (ICC>0.9 between all observers). Receiver operating characteristic curve analysis showed that the predictive power for CAD was improved when max-CIMT and plaque information (plaque≥2) was added [area under the curve (AUC): 0.838] to the traditional clinical CV risk factors (AUC: 0.769). The cutoff values for CAD prediction with the standard device and the WHUS device were 1.05 mm (AUC: 0.807, sensitivity: 0.78, specificity: 0.53) and 1.10 mm (AUC: 0.725, sensitivity: 0.98, specificity: 0.27), respectively. Conclusion max-CIMT measured by a WHUS device showed excellent agreement and repeatability, compared with standard ultrasound. Combined max-CIMT and plaque information added predictive power to the traditional clinical CV risk factors in detecting high-risk CAD patients.

Portable ultrasound is recently emerging as a new medical imaging modality featuring high portability, easy connectivity, and real-time on-site diagnostic ability. However, it does not yet provide ultrasound elastography function that enables the diagnosis of malignant lesions using elastic properties. This is mainly due to the limitations of hardware performance and wireless data transfer speed for processing the large amount of data for elastography. Therefore, data transfer reduction is one of the feasible solutions to overcome these limitations. Recently, compressive sensing (CS) theory has been rigorously studied as a means to break the conventional Nyquist sampling rate and thus can significantly decrease the amount of measurement signals without sacrificing signal quality. In this research, we implemented various CS reconstruction frameworks and comparatively evaluated their reconstruction performance for realizing ultrasound elastography function on portable ultrasound. Combinations of three most common model bases (Fourier transform [FT], discrete cosine transform [DCT], and wave atom [WA]) and two reconstruction algorithms (L1 minimization and block sparse Bayesian learning [BSBL]) were considered for CS frameworks. Echoic and elastography phantoms, were developed to evaluate the performance of CS on B-mode images and elastograms. To assess the reconstruction quality, mean absolute error (MAE), signal-to-noise ratio (SNRe), and contrast-to-noise ratio (CNRe) were measured on the B-mode images and elastograms from CS reconstructions. Results suggest that CS reconstruction adopting BSBL algorithm with DCT model basis can yield the best results for all the measures tested, and the maximum data reduction rate for producing readily discernable elastograms is around 60%.

Organic waste used as a feedstock in the anaerobic digestion (AD), it includes carbon and nitrogen. Carbon and nitrogen have an effect on the various digestive characteristics during AD, however, the study is rare about those of the interaction. This study investigates the influence of carbon type and carbon to nitrogens (C/N ratios) on the AD characteristics of organic waste. Experimental treatments involved a combination of three carbon types with three C/N ratios. The AD tests were carried out using a 125-mL serum bottle at a constant temperature of 37°C and moisture 95% for 18 days. Degradation pattern shows the difference among three-carbon treatments, the starch group was faster than other groups. Maximum methane production date was similar between starch (9.96 ± 0.05 day) and xylan group (10.0 ± 0.52 day), those of the cellulose group (14.6 ± 1.80 day) was slower than other groups (p < 0.05). The lag phase was only affected by the carbon type (p < 0.05). Ammonia nitrogen was mainly affected by nitrogen concentration regardless of carbon type (p < 0.05). This study showed that xylan is useful as feedstock in order to decrease the lag phase, and it showed that ammonia was independently affected by the nitrogen concentration.

The introduction of BIM into complex buildings is essential and open BIM environment for communication between different kinds of work is an important element with the increasing demand for freeform buildings considering the value as being landmarks. IFC which is a standard integration model in the construction industry has been developed in buildingSMART International aiming for the interoperation of different information model tools. IFC is not only compatible for geometry information but also compatible for property information of the construction, and the standard protocol for data exchange in CAD tool representing BIM has been established for IFC. However, extensive time and costs have been spent since the geometry information is separately established and utilized in the certain software due to poor communication regarding precise geometry information in free-from projects of large scale. Information delivery has been insufficient because of not using BIM authoring tools but CAD-tools. The purpose of this study was to propose the process allowing the conversion of free-from shape into IFC file and the conversion with BIM software by coding the information regarding complex shape of free-from buildings. For this, the improvement in compatibility for geometry information and property information of free-form buildings is expected and improvement in communication and reduction in work duration and costs in different works in each area of the construction industry handling complex shape and property information are ultimately expected.

Portable wireless ultrasound has been emerging as a new ultrasound device due to its unique advantages including small size, lightweight, wireless connectivity and affordability. Modern portable ultrasound devices can offer high quality sonogram images and even multiple ultrasound modes such as color Doppler, echocardiography, and endovaginal examination. However, none of them can provide elastography function yet due to the limitations in computational performance and data transfer speed of wireless communication. Also phase-based strain estimator (PSE) that is commonly used for conventional elastography cannot be adopted for portable ultrasound, because ultrasound parameters such as data dumping interval are varied significantly in the practice of portable ultrasound. Therefore, this research aims to propose a new elastography method suitable for portable ultrasound, called the robust phase-based strain estimator (RPSE), which is not only robust to the variation of ultrasound parameters but also computationally effective. Performance and suitability of RPSE were compared with other strain estimators including time-delay, displacement-gradient and phase-based strain estimators (TSE, DSE and PSE, respectively). Three types of raw RF data sets were used for validation tests: two numerical phantom data sets modeled by an open ultrasonic simulation code (Field II) and a commercial FEA (Abaqus), and the one experimentally acquired with a portable ultrasound device from a gelatin phantom. To assess image quality of elastograms, signal-to-noise (SNRe) and contrast-to-noise (CNRe) ratios were measured on the elastograms produced by each strain estimator. The computational efficiency was also estimated and compared. Results from the numerical phantom experiment showed that RPSE could achieve highest values of SNRe and CNRe (around 5.22 and 47.62 dB) among all strain estimators tested, and almost 10 times higher computational efficiency than TSE and DSE (around 0.06 vs. 5.76 s per frame for RPSE and TSE, respectively).

Real-time functional MRI (rtfMRI) has been used as a basis for brain–computer interface (BCI) due to its ability to characterize region-specific brain activity in real-time. As an extension of BCI, we present an rtfMRI-based brain–machine interface (BMI) whereby 2-dimensional movement of a robotic arm was controlled by the regulation (and concurrent detection) of regional cortical activations in the primary motor areas. To do so, the subjects were engaged in the right- and/or left-hand motor imagery tasks. The blood oxygenation level dependent (BOLD) signal originating from the corresponding hand motor areas was then translated into horizontal or vertical robotic arm movement. The movement was broadcasted visually back to the subject as a feedback. We demonstrated that real-time control of the robotic arm only through the subjects’ thought processes was possible using the rtfMRI-based BMI trials.

Communication is totally the most important factors in the building environment. IFC is construction industry standard integrated model. IFC had been developed for interoperability of different information modeling tools. It is compatible with the architectural geometric information modeling tools. It is compatible with the architectural geometric information as well as architectural properties Due to the increasing trend in the value of freeform building’s landmark, BIM is essential about complex building. Open-BIM environment is important factor for communication between each other. Geometric information is not perfectly transfer each other tool in large scale freeform building project. Use of BIM about freeform building spends a lot of cost and time because of separately drawing only in specific tool. Aim of this study defines the information of complex geometric in the freeform building. It proposed to interoperability process by converting freeform geometry into IFC file. This study will improve interoperability of geometric and properties about freeform building. It will improve communication about each other task in the fields of construction industry.

This research presents the integration of 4D CAD with RFID (Radio Frequency IDentification) technology to improve the progress management process. The objective of this research was to build an effective and efficient project progress management framework by integrating 4D CAD with RFID technology under a collaborative environment throughout the supply chain of a construction project. This research proposes a system, named 4D+RFID, that presents building elements in 3D CAD models according to as-built progress, where the as-built information is collected in real-time by sensing the progress throughout the supply chain using RFID. 4D+RFID developed in this research aims at supporting processes with a focus on structural and curtain wall elements, such as steel columns and beams, concrete slabs, and curtain walls, which are typically on the critical path of project schedules in high-rise building construction projects. The process is that RFID is applied to sense the progress status of ordering, delivery, receiving, and erection of building elements, and then the as-built progress information is presented in 3D CAD models. 4D+RFID is under development for use in a high-rise office building construction project in downtown Seoul, Korea.