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This paper analyzed 19 precast concrete (PC) construction project cases from Korea using fuzzy-set qualitative comparative analysis to explore the relationship between the conditions of PC projects, observable at an early stage of the projects, and actual schedule delays. The following combinations of PC project conditions leading to schedule delays were identified: (1) the use of multiple types of PC components and nonuse of building information modeling (BIM) for schedule management; (2) PC construction included in the critical path, insufficient experience of the contractor in PC projects, and nonuse of BIM for schedule management; and (3) nonresidential building project, insufficient experience of the contractor in PC projects, and non-use of BIM for schedule management. To understand these findings more deeply, this research further investigated the relationships of the use of BIM with other schedule delay factors based on focus groups. The PC project schedule delay leading indicators identified in this research can help construction managers to mitigate schedule delay risks at an early stage in PC projects. Refereed/Peer-reviewed

Very little is known about the project risk factors that affect construction management (CM) firms, which often struggle due to a lack of effective risk management practices. This study investigates the risk factors critical to project execution in CM firms and ranks them using the analytic hierarchy process (AHP) and failure mode and effects analysis (FMEA) methods. Interviews with executives at the top 15 Korean CM firms are carried out to identify major risk factors in the CM sector, and a survey is used to develop priority ranking. We find that payment delays and project delays are the two most critical risk factors affecting CM firms because of (1) lack of communication between headquarters and field offices, (2) shift of responsibility from headquarters to a field office, (3) absence of regular monitoring of project progress, and (4) ex-post management practices. The findings presented in this study should assist CM firms in establishing more robust risk management practices, thereby improving firms’ profitability, project performance, and customer satisfaction.

Controversy exists regarding the involvement of the primary motor cortex (M1) during motor imagery (MI) and also regarding the differential somatotopic representation of motor execution (ME) and mental simulation of movement, that is, MI within M1. Although some research reported clear M1 involvement during MI without overt motor output, others did not. However, possible somatotopic representation between execution and imagery has not been clearly investigated to date. The aim of the present study was to aid in the resolution of this controversy by investigating the possible involvement of M1 during MI, and the differential, within M1, somatotopic representation between execution and imagery by quantitatively assessing different location markers such as activation peak and center of mass as well as intensity differences between the two tasks in case of with and without the overlap between the two representations. Forty-one healthy volunteers participated in two functional MRI runs of mouth-stretching ME and MI tasks. Our findings suggest the clear involvement of M1 (BA 4) during MI with lower signal intensity compared with ME, and further showed distinct centers for each representation along the y-axis (anteroposterior plane), with MI showing more involvement of the anterior sector of M1 (BA 4a), whereas ME recruited more of the posterior sector (BA 4p). These results parallel the pioneering findings of a functional distinction between BA 4a and BA 4p, where BA 4a is more involved in the cognitive aspects of MI, whereas BA 4p is more related to executive function, promoting the idea of distinctive somatotopic mapping between execution and imagery within M1 sectors.

The measured electroencephalographic (EEG) signals used in brain–computer interface (BCI) are usually contaminated with several additive random and physiological noise components. Even though several preprocessing strategies were proposed in the literature to extract useful EEG signal components for further processing and analysis, their performance is yet to meet practical needs to boost BCI applications performance. Of particular interest among those methods are the ones addressing random noise suppression that could help enhance the performance of low-cost BCI systems/headsets. A preprocessing block for signal denoising of slow cortical potential (SCP) that provides efficient noise removal and better classification accuracy is presented. This method is a variant of the spectral subtraction signal denoising whereby the noise power spectrum is estimated and removed adaptively. This method is applied to each EEG channel separately thus providing a preprocessing block that could be integrated with the existing spatial/temporal preprocessing methods. The impact of this method on classification accuracy is studied and compared to the conventional wavelet shrinkage method. The proposed method is verified using experimental data from the BCI competition II data set whereby a performance boost was obtained with the new preprocessing block. The improvement was quantitatively assessed using mean square error and mean absolute error measures and was also shown to be statistically significant. Moreover, spectral subtraction denoising is shown to have less computational complexity than wavelet shrinkage based methods. The new preprocessing block for SCP-based BCI signals based on spectral subtraction provides significant improvement in performance when added and offers an adaptive yet less computationally expensive alternative to existing methods such as wavelet shrinkage based denoising method. Also, given its independent channel processing, it shows potential for seamless integration into conventional processing chain for different BCI applications.

Motor imagery (MI) relies on conscious mental simulation of a motor act without overt motor output and can promote motor skill acquisition and facilitate rehabilitation for patients with stroke or neurological conditions. Although a plethora of neuroimaging studies have investigated the neural network of MI regarding different body parts, exploration of the neural correlates to facial MI remains warranted. Here, we used functional MRI with a large cohort of 41 participants who underwent motor execution (ME) and MI runs of mouth-stretching tasks. Then, we carried out conjunction and contrast analyses to investigate the commonalities and differences between the two conditions. Conjunction analysis, representing the shared neural network between ME and MI, showed activation in the primary motor cortex, primary and secondary somatosensory cortices, premotor cortex, parietal lobe, anterior insula, supplementary motor area (SMA) and pre-SMA, thalamus, putamen, and caudate. Contrast analysis showed greater activation of primary motor cortex, primary and secondary somatosensory cortices, SMA, anterior insula, and the thalamus in response to ME than MI and greater activation of the premotor cortex, pre-SMA, putamen, and caudate in response to MI than ME. Interestingly, we found exclusive activation in the anterior cingulate cortex and left ventrolateral prefrontal cortex in response to MI, reflecting the motor inhibition network responsible for blocking the transmission of motor commands to peripheral effectors during mental rehearsal. Taken together, these findings show that, despite the neural overlap between ME and MI, there are different degrees of activation within this overlap, and that MI normally involves motor command inhibition possibly mediated by the anterior cingulate cortex and ventrolateral prefrontal cortex.

Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) Checklist. (DOC 138 kb)

Standards for Reporting Interventions in Clinical Trials of Acupuncture (STRICTA). (DOC 55 kb)

Construction management firms in Korea have mainly focused on the key management areas of time, cost, quality and safety management in line with a rapid change of construction industry recently. However, a risk management is considered comparatively less important found from our research on an investment by the firms for training, system establishment. This has been identified that the construction management firms have taken an approach of dealing with risks with their experience, insight rather than managing risks with a systemized principles or proper tools. Therefore, the current system for risk management was identified by analyzing risk factors and work process in this research and systemized process for risk management of the identified risk factors was suggested. This research is expected to be a basis on establishing standard gudiance for risk management and risk management tools.

Although acupuncture is an effective therapeutic intervention for pain reduction, the exact difference between real and sham acupuncture has not been clearly understood because a somatosensory tactile component is commonly included in the existing sham acupuncture protocols. In an event-related fMRI experiment, we implemented a novel form of sham acupuncture, phantom acupuncture, that reproduces the acupuncture needling procedure without somatosensory tactile stimulation while maintaining the credibility of the acupuncture treatment context. Fifty-six non-specific low back pain patients received either real (REAL) or phantom (PHNT) acupuncture stimulation in a parallel group study. The REAL group exhibited greater activation in the posterior insula and anterior cingulate cortex, reflecting the needling-specific components of acupuncture. We demonstrated that PHNT could be delivered credibly. Interestingly, the PHNT-credible group exhibited bilateral activation in SI/SII and also reported vicarious acupuncture sensations without needling stimulation. The PHNT group showed greater activation in the bilateral dorsolateral/ventrolateral prefrontal cortex (dlPFC/vlPFC). Moreover, the PHNT group exhibited significant pain reduction, with a significant correlation between the subjective fMRI signal in the right dlPFC/vlPFC and a score assessing belief in acupuncture effectiveness. These results support an expectation-related placebo analgesic effect on subjective pain intensity ratings, possibly mediated by right prefrontal cortex activity.

Bell's palsy is the most common cause of acute facial nerve paralysis. In China, Bell's palsy is frequently treated with acupuncture. However, its efficacy and underlying mechanism are still controversial. In this study, we used functional MRI to investigate the effect of acupuncture on the functional connectivity of the brain in Bell's palsy patients and healthy individuals. The patients were further grouped according to disease duration and facial motor performance. The results of resting-state functional MRI connectivity show that acupuncture induces significant connectivity changes in the primary somatosensory region of both early and late recovery groups, but no significant changes in either the healthy control group or the recovered group. In the recovery group, the changes also varied with regions and disease duration. Therefore, we propose that the effect of acupuncture stimulation may depend on the functional connectivity status of patients with Bell's palsy.

Project Management Information System (PMIS) has not yet fully met needs of the construction industry. Based on the deficiency of the current system, the present study performed a survey to identify a need for mobile PMIS in the industry. The survey revealed that most respondents expect the development of mobile PMIS would contribute to improving the productivity and efficiency of field operations. Based on the survey findings, this study proposes a suite of modules for mobile PMIS, which are focused on construction management, document management, schedule management, and field information management. Mobile PMIS would allow to access from the field through mobile devices by using tablet computers and smart-phones. The study also suggests that the effectiveness of the system can be enhanced by user interfaces that are customized for each module.

The Korean construction industry has been severely impacted by the 2008 global financial crisis, which resulted in a significant reduction in the overall contract amount. For survi val, many construction management (CM) companies had to adapt a strategy of lowering bid prices to maintain their competitive ness. As a result of the strategy, companies faced a number of issues including their decreased capability in risk management. However, most risk management-related studies focused on construction risk management, yet these studies lacked consider ation of enterprise-level risk management practices. To fill th e gap, the objectives of the present study are (1) to investigate, the risk management practices of Korean CM companies, (2) to identify factors that determine efficient enterprise-level risk management practices, and (3) to propose a module for the development of enterprise-level risk management. Lastly, the ef ficiency of the proposed development module was validated by using a survey.Keyword : CM enterprise, Risk management condition analysis, Suggest eff icient management methodology

It is a difficult thing to administer a various task in the construction site because, the person placing an order are eagerly demanding for the reduction of project duration as the trend of construction are becoming larger and international. The advanced country have made an effort to development PMIS based on the Web, which to exchanges a various construction information such as Time Management/Construction Management/Resource Management/Document Management to solve these problems since 2000. However, the expectation to develop a smart PMIS that can deal with a more quick change of a various process are becoming lager as the lively supply of IT equipment such as smart phone and table PC. The research are aim to develop the next generation smart PMIS, which is link with the table PC and smart phone for a site manager to use the system based on the web in the movement. Also, it has an object in view to introduce the development process and the major function of the next generation PMIS.

Since high-rise building construction sites are usually located in crowded city areas, sufficient spaces for the inventories of key materials are rarely available. This spatial constraints have been one of the critical challenge that may cause productivity loss and increasing costs of the high-rise building construction projects. The proper material inventory management is certaing a key to the success of high-rise building construction projects as it handles difficulty of securing material stock yards, changes in demands, uncertain delivery time through integrating the construction schedules and actively responding to the key materials attributes. In this light, this research analyzes the latest inventory model, (Q,r) model, in accordance with the high rise building characteristics. This research suggests an optimal inventory management of re-bar considering various demands and lead times. The case study is also presented with regard to the re-bar inventory management.

To develop differential criteria on the tongue coating thickness (TCT), and especially propose the standard for judgment on thin and thick coating in tongue diagnosis.Sixty oriental medical doctors evaluated the TCT (none, thin, and thick coating) in 50 realistic tongue photographs revealing from tip-to-root. The photographs were obtained with a digital tongue imaging system (DTIS) which measured the percentages of tongue coating on the tongue surface. We calculated the match rate which is the ratio in which the assessor's judgment is consistent with the decision standard on the tongue coating, and then 24 assessors (≥80% match rate) were selected to improve the reliability of the decision. The agreement level among 24 assessors was examined to assess the inter-rater reliability. The correlation between TCT judgments and DTIS-measured values was examined to ascertain the reliability of DTIS measurements. Finally, the assumption probability for the analysis of quantified characteristics of the tongue coating was calculated with a proportional odds model.The inter-rater reliability was assessed as moderate (κ=0.56) among 24 assessors, the level of correlation between TCT judgments and DTIS measurements in 24 assessors was relatively high (0.76, p0.01). As the analysis of the proportional odds model, 29.06% was a cut-off point to separate no coating and thin coating, 63.51% was a cut-off point to separate thin and thick coating.The differential criteria for TCT in tongue diagnosis were suggested, and particularly thick coating is defined as one that tongue coating which tongue body is invisible, occupy approximately more than two third areas on the tongue surface.

Functional dyspepsia (FD) is a prevalent gastric disorder that is difficult to manage due to lack of satisfactory treatments. Acupuncture has been studied with regard to the rising need for treating FD, but the mechanism verifying its efficacy has not yet been fully revealed. The aim of this study is to explore the efficacy and mechanism of acupuncture for FD compared with a sham group. We describe a proposal for a randomized, assessor-blind, sham-controlled trial with 70 eligible participants who will be randomly allocated either into an acupuncture or a sham group. Participants in the acupuncture group will receive 10 sessions of real acupuncture treatment and those in the sham group will be treated with identical sessions using a Streitberger needle. Functional magnetic resonance imaging (fMRI) and metabolomics studies will be implemented before and after 4 weeks of treatment to investigate the mechanism of acupuncture. The primary outcome is a proportion of responders with adequate symptom relief and the secondary outcomes include the Nepean Dyspepsia Index - Korean version, Functional Dyspepsia-Related Quality of Life questionnaire, Ways of Coping Questionnaire, Coping Strategies Questionnaire, perception of bodily sensation questionnaire, State-Trait Anxiety Inventory, and the Center for Epidemiological Studies - Depression Scale. The outcomes will be evaluated before and after the treatment. This is the first large-scale trial evaluating the efficacy and mechanism of acupuncture with fMRI and metabolomic methods. We will compare real acupuncture with the Streitberger sham needle to verify the specific effect of acupuncture. The results of this trial are expected to be relevant evidences affecting policy and decision-makers associated with routine healthcare. ClinicalTrials.gov Identifier: NCT02358486 . Date of Registration: 21 January 2015.

Objective. Abdominal examination (AE) is one of the essential diagnostic methods in traditional Korean medicine that has been widely used for deciding treatment, cause, and prognosis of the disease. AE majorly depends on the experience of practitioners; therefore, standardization and quantification of AE are desperately needed. However, few studies have tried to objectify AE and established its standard. We assessed the reliability and validity of newly developed diagnostic device for AE called modified algometer (MA).Methods. Thirty-six subjects with functional dyspepsia were allocated into one of 2 groups according to gold standard of AE: epigastric discomfort without tenderness (n=23) group or epigastric discomfort with tenderness (n=13) group. Pressure pain threshold was evaluated at participants’ epigastric region with algometer and MA. We assessed reliability and validity (sensitivity and specificity) and calculated optimal cutoff value.Results. MA showed high intertrial reliability (ICC 0.849; 0.703–0.923;P<0.000) and validity (sensitivity: 76.92%; specificity: 60.87%), and cutoff value was 330.0 mmHg. Algometer and MA showed moderate correlation (r=0.583,P≤0.000).Conclusion. MA can be reliable and valid diagnostic device for AE and has the possibility of practical use for quantification and standardization of AE.