Efficiency Analysis of Project Management Offices for Large-scale Information System Projects: Insights for Construction Megaprojects

In this study, the efficiencies of Project Management Offices (PMOs) in large-scale information system (IS) projects are addressed by using data envelopment analysis. Moreover, the potential improvement levels for each input and output factors of inefficient PMOs are examined. The effects of performance levels of PMO functions on project outcomes with respect to efficiency levels are also analyzed. A total of forty-nine PMOs are analyzed for this study. The result shows that twenty-four PMOs are found to be efficient. As a result of analyzing the impact of efficiency on project performance depending on the functional levels of PMOs, those groups with a high degree of efficiency show higher outcomes compared with the groups with a low degree of efficiency regardless of the functional levels of PMOs. Furthermore, the gap in outcome between the groups with a high degree of efficiency and the groups with a low degree of efficiency is maintained at almost the same level, regardless of the functional levels of PMOs, with the exception of the case of practice management. This indicates that even those groups with a low degree of efficiency could expect high outcomes in terms of schedule and cost compliance if their level of practice management is high

Bacterial community analysis in upflow multilayer anaerobic reactor (UMAR) treating high-solids organic wastes

A novel anaerobic digestion configuration, the upflow multi-layer anaerobic reactor (UMAR), was developed to treat high-solids organic wastes. The UMAR was hypothesized to form multi-layer along depth due to the upflow plug flow; use of a recirculation system and a rotating distributor and baffles aimed to assist treating high-solids influent. The chemical oxygen demand (COD) removal efficiency and methane (CH4) production rate were 89% and 2.10 L CH4/L/day, respectively, at the peak influent COD concentration (110.4 g/L) and organic loading rate (7.5 g COD/L/day). The 454 pyrosequencing results clearly indicated heterogeneous distribution of bacterial communities at different vertical locations (upper, middle, and bottom) of the UMAR. Firmicutes was the dominant (>70%) phylum at the middle and bottom parts, while Deltaproteobacteria and Chloroflexi were only found in the upper part. Potential functions of the bacteria were discussed to speculate on their roles in the anaerobic performance of the UMAR system

Autologous collagen-induced chondrogenesis: From bench to clinical development

Microfracture is a common technique that uses bone marrow components to stimulate cartilage regeneration. However, the clinical results of microfracture range from poor to good. To enhance cartilage healing, several reinforcing techniques have been developed, including porcine-derived collagen scaffold, hyaluronic acid, and chitosan. Autologous collagen-induced chondrogenesis (ACIC) is a single-step surgical technique for cartilage regeneration that combines gel-type atelocollagen scaffolding with microfracture. Even though ACIC is a relatively new technique, literature show excellent clinical results. In addition, all procedures of ACIC are performed arthroscopically, which is increasing in preference among surgeons and patients. The ACIC technique also is called the Shetty–Kim technique because it was developed from the works of A.A. Shetty and S.J. Kim. This is an up-to-date review of the history of ACIC

Improving Exploration And Exploitation Capability Of Harmony Search Algorithm

Harmony Search (HS) is a meta-heuristic algorithm which was first introduced in 2001 and it became a widely used optimization algorithm in various areas in engineering application as well as in water resources planning and management. However, as most meta-heuristic algorithms are, the HS shows a good performance in global search but not as good in local search. This study aims the improvement of both exploration and exploitation capability of the algorithm. The mission has been carried out by changing algorithm operators or parameters in the search process. Several types of Improved Harmony Search (IHS) have been successfully developed resulting better exploiting (local) search. Alternative way is to utilize the superior local search of other models or algorithms. The combined, so called hybrid algorithms can significantly supplement the weak local search aspect of the original HS. A newly developed hybrid algorithm, Smallest Small World Cellular Harmony Search (SSWCHS), is developed and proposed shorter characteristic path length and higher clustering coefficient, resulting good exploration and exploitation efficiency. Application to benchmark functions and design of pipe networks proves the superior performance of the newly developed hybrid algorithm

Application Of Water Cycle Algorithm For Optimal Cost Design Of Water Distribution Systems

Water distribution system (WDS) design is considered as a class of large combinatorial non-linear optimization problems having complex implicit constraints such as conservation of mass and energy equations. Due to the complexity and large feasible solution, traditional optimization techniques are not capable to tackle these kinds of problems. Recently, applications of metaheuristic algorithms, due to their efficiencies and performances, are increased dramatically. In this paper, water cycle algorithm (WCA), a recently developed population-based algorithm, coupled with hydraulic simulator, EPANET, are applied for finding the optimal cost design of WDS. The performance of the WCA is shown using well-known Balerma benchmark problem widely used in the literature. The obtained optimization results using the WCA are compared with other optimizers such as genetic algorithm, simulated annealing, and harmony search. Comparisons of obtained statistical results show the superiority of the WCA over other optimization methods in terms of convergence rate and solution quality

Current Management and Future Strategies of Gastric Cancer

The overall prognosis of gastric cancer has gradually improved over the past decades with growing awareness of potential carcinogens, surveillance programs and early diagnosis, as well as advances in surgical techniques and multimodality treatments. Nevertheless, the outcome of advanced stage disease still remains poor with currently available treatments, and a worldwide consensus on the standard management thereof has not been established. To improve prognosis and quality of life in gastric cancer patients, both standardization and individualization of managements are imperative. Diagnostic tests and surgical procedures need to be further sophisticated and standardized based on more recent evidences from ongoing and future randomized controlled trials, while comprehensive management should be individualized to each patient. Future challenges lie with how to optimize personalized therapies by deciphering biological complexity of gastric cancer and incorporating molecular biomarkers in clinical practice to forecast prognosis and to guide targeted therapeutics in adjunct to current standards of care

Development of Practical Design Approaches for Water Distribution Systems

The optimal design of water distribution systems (WDSs) should be economical, consider practical field applicability, and satisfy hydraulic constraints such as nodal pressure and flow velocity. However, the general optimal design of a WDSs approach using a metaheuristic algorithm was difficult to apply for achieving pipe size continuity at the confluence point. Although some studies developed the design approaches considering the pipe continuity, these approaches took many simulation times. For these reasons, this study improves the existing pipe continuity search method by reducing the computation time and enhancing the ability to handle pipe size continuity at complex joints that have more than three nodes. In addition to more practical WDSs designs, the approach considers various system design factors simultaneously in a multi-objective framework. To verify the proposed approach, the three well-known WDSs to apply WDS design problems are applied, and the results are compared with the previous design method, which used a pipe continuity research algorithm. This study can reduce the computation time by 87% and shows an ability to handle complex joints. Finally, the application of this practical design technique, which considers pipe continuity and multiple design factors, can reduce the gap between the theoretical design and the real world because it considers construction conditions and abnormal situations.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Smallest-Small-World Cellular Harmony Search for Optimization of Unconstrained Benchmark Problems

We presented a new hybrid method that combines cellular harmony search algorithms with the Smallest-Small-World theory. A harmony search (HS) algorithm is based on musical performance processes that occur when a musician searches for a better state of harmony. Harmony search has successfully been applied to a wide variety of practical optimization problems. Most of the previous researches have sought to improve the performance of the HS algorithm by changing the pitch adjusting rate and harmony memory considering rate. However, there has been a lack of studies to improve the performance of the algorithm by the formation of population structures. Therefore, we proposed an improved HS algorithm that uses the cellular automata formation and the topological structure of Smallest-Small-World network. The improved HS algorithm has a high clustering coefficient and a short characteristic path length, having good exploration and exploitation efficiencies. Nine benchmark functions were applied to evaluate the performance of the proposed algorithm. Unlike the existing improved HS algorithm, the proposed algorithm is expected to have improved algorithmic efficiency from the formation of the population structure