BIM functions for optimized construction management in civil engineering

Purpose The aim of this study is to suggest configuration methodologies of active building information model (BIM) functions that enable to practically control limitations by optimizing schedule overlapping linked to its space models after analyzing workspace conflict analysis for a bridge model. This study also suggests development methodologies of active BIM-functions, linking an optimized method and improved strategies of future BIM-operation model through an analysis of limitations of a passive BIM-operation system for architectural projects. Method The existing BIM-system manually performed a simplified comparison review of 3D-shapes and its virtual reality (VR) analysis with visual manipulation of 3D-models in a virtual environment. Such BIM functions require a separate analysis process to organize BIM-output data as reprocessed business data. This has many limitations when directly utilizing the visual information produced by commercial BIM-systems as practical operation data. Accordingly, this study develops functions of an active BIM-system so that the managers can directly analyze practical requirements by integrating an optimized analysis algorithm with the BIM-system to improve the passive BIM operation environments. As a method of configuring the active BIM-functions, an optimized algorithm for establishing resolution strategies for workspace conflicts is constructed. As functions for supporting active BIM-operations, this study utilizes fuzzy and genetic algorithm (GA) approaches. These approaches will be used to develop visualized risk assessment model and workspace conflict optimization model based on active BIM. Results & Discussion By enhancing fragmentary analysis functions of simplified 3D-models with the development of an active BIM-system, the BIM-system can utilize output information derived from a process of analysis, evaluation and control of the BIM-models as a practical operation information model for both design and construction phase. Therefore, it is expected that an active BIM can simplify data analysis and the system operation process for managers with virtual object models and expand the active BIM-system to the life cycle of civil engineering projects

The Efficacy of the Prophylactic Use of Octreotide after a Pancreaticoduodenectomy

This study was performed to analyze the efficacy of the prophylactic use of octreotide (Novartis, Stein, Switzerland) for pancreatic fistula following a pancreaticoduodenectomy. The medical records of 190 patients who underwent a pancreaticoduodenectomy at the Samsung Medical Center in Seoul, Korea between January 2000 and December 2002 were reviewed. Patients were divided into either the octreotide (n = 81) or control group (n = 109). The octreotide group received subcutaneous injections of 100 µg of octreotide every 12 hours for more than five days after surgery. The control group was not treated with octreotide. The criterion of pancreatic fistula was the drainage of the amylase rich fluid, over 500 U/mL in the three days after surgery. The morbidity and mortality rates were 32.1% and 1.2% in the octreotide group and 31.2% and 0% in the control group, respectively. Pancreatic fistula was the second most common complication (8.4%). In the univariate analysis, octreotide was ineffective in reducing pancreatic fistula (p = 0.26). However, in the multivariate regression analysis, combined gastrectomy (p = 0.018), cellular origin of the disease (p = 0.049), and use of octreotide (p = 0.044) were the risk factors that increased the frequency of pancreatic fistula. Therefore, the routine use of octreotide after a pancreaticoduodenectomy should be avoided until a worldwide consensus is established

The usefulness of non-invasive liver stiffness measurements in predicting clinically significant portal hypertension in cirrhotic patients: Korean data

Background/AimsLiver stiffness measurement (LSM) has been proposed as a non-invasive method for estimating the severity of fibrosis and the complications of cirrhosis. Measurement of the hepatic venous pressure gradient (HVPG) is the gold standard for assessing the presence of portal hypertension, but its invasiveness limits its clinical application. In this study we evaluated the relationship between LSM and HVPG, and the predictive value of LSM for clinically significant portal hypertension (CSPH) and severe portal hypertension in cirrhosis.MethodsLSM was performed with transient elastography in 59 consecutive cirrhotic patients who underwent hemodynamic HVPG investigations. CSPH and severe portal hypertension were defined as HVPG ≥10 and ≥12 mmHg, respectively. Linear regression analysis was performed to evaluate the relationship between LSM and HVPG. Diagnostic values were analyzed based on receiver operating characteristic (ROC) curves.ResultsA strong positive correlation between LSM and HVPG was observed in the overall population (r2=0.496, P<0.0001). The area under the ROC curve (AUROC) for the prediction of CSPH (HVPG ≥10 mmHg) was 0.851, and the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for an LSM cutoff value of 21.95 kPa were 82.5%, 73.7%, 86.8%, and 66.7%, respectively. The AUROC at prediction of severe portal hypertension (HVPG ≥12 mmHg) was 0.877, and the sensitivity, specificity, PPV, and NPV at LSM cutoff value of 24.25 kPa were 82.9%, 70.8%, 80.6%, and 73.9%, respectively.ConclusionsLSM exhibited a significant correlation with HVPG in patients with cirrhosis. LSM could be a non-invasive method for predicting CSPH and severe portal hypertension in Korean patients with liver cirrhosis

Standard First-line Triple Therapy for Helicobacter pylori Infection: A Comparison of Eradication Rates Based on Timing of Administration of Proton Pump Inhibitors

Background/Aims: Recent Korean studies performed over the past few decades have shown diminishing efficacy and unacceptability of clarithromycin-based triple therapy as first-line eradication therapy for Helicobacter pylori infection, based on evidence of a declining eradication rate. Triple therapy continues to be used as first-line eradication therapy despite concerns regarding high clarithromycin resistance among Koreans. Patient compliance and acid suppression are important factors associated with the H. pylori eradication rate. We investigated whether regular administration of a proton pump inhibitor (PPI) 30 minutes before a meal can improve the eradication rate. Materials and Methods: We retrospectively analyzed the data of 316 patients who were treated with first-line triple therapy (PPI, amoxicillin, and clarithromycin) for H. pylori infection between January 2012 and September 2017. Patients were divided into 2 groups based on the time of administration of the PPI (group A: before a meal, group B: after a meal). The urea breath test was performed 4∼6 weeks after eradication of infection. Results: Notably, 249 patients (78.8%, 249/316) showed successful eradication. The eradication rates in groups A and B were 87.5% (49/56 patients) and 76.9% (200/260 patients), respectively. We observed that regular administration of PPI before meals improved the eradication rate (P=0.079). Conclusions: We observed that although clarithromycin-based triple therapy was associated with an overall eradication rate ＜80%, regular PPI administration before meals improved the eradication rate. Regular PPI administration before meals and effective education to improve patient compliance could improve the eradication rate through maximal acid suppression