Search

The disturbance of local areas with complex railway networks and high traffic density not only impedes the efficient use of rail networks in those areas, but also propagates delays to the entire railway network. This has motivated research on train rescheduling problems in high-density local areas to minimize train delays by modifying their planned arrival and departure times. In this paper, we present a train rescheduling method based on Q-learning in reinforcement learning. More specifically, we used deep neural networks to approximate the action-value function, and the underlying Markov decision process (MDP) is based on the alternative graph formulation for the train rescheduling problem. In the proposed MDP formulation, the status of the alternative graph corresponding to the current schedule is defined as the state, and the alternative arc corresponds to the action the agent can take. The MDP is approximately solved via deep Q-learning in which deep neural networks are used to approximate the action-value function in Q-learning. Although the size of the alternative graph depends on the number of trains, our MDP formulation is independent of the number of trains, which makes the proposed method more scalable. The evaluation of the method was performed on a simple railway network and a real-world example in Seoul, South Korea, with randomly generated initial train schedules and train delays. The experimental result showed that the proposed method is comparable to the mixed-integer-linear-programming (MILP)-based exact approach with respect to the quality of the solution. [ABSTRACT FROM AUTHOR]

This paper explores whether the population size of the Seoul Metropolitan Area (SMA) in Korea is efficient in terms of the national economy. To undertake this analysis, a recursively dynamic interregional computable general equilibrium (ICGE) model with a population module is developed. In this model, the explicit costs and benefits of population growth are estimated by using the industrial value added and consumer price inflation functions for each region. The counter-factual analysis shows that national population decentralisation away from the SMA is desirable for Korea’s economic growth. Korea’s GDP is estimated to be maximised when the SMA’s national population share is at 39 per cent in the short term and 35 per cent in the long term. However, the SMA government is likely to have incentive to maintain its population at around 40 per cent of the national population, where per capita income at the regional, not national, level is maximised. [ABSTRACT FROM PUBLISHER]

Copyright of International Journal of Strategic Property Management is the property of Vilnius Gediminas Technical University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: To compare clinical outcomes of a 1.8 mm and a 2.2 mm microcoaxial cataract surgery system. Setting: Department of Ophthalmology and Visual Science, Kangnam St. Mary''s Hospital, College of Medicine, Catholic University of Korea, Seoul, Korea. Methods: In a prospective study, eyes were randomly selected to have phacoemulsification using a Stellaris system or an Intrepid Infiniti system. The initial incision size was 1.8 mm and 2.2 mm, respectively. Measured intraoperative parameters included phacoemulsification time, mean cumulative dissipated ultrasound energy (CDE), change in incision size at each step of surgery, and total volume of balanced salt solution (BSS) used. The best corrected visual acuity (BCVA), corneal astigmatism, corneal thickness, and endothelial cell count were evaluated preoperatively and postoperatively. Results: The study evaluated 86 eyes of 78 patients (43 eyes in each group). There were no significant differences in postoperative BCVA, surgically induced astigmatism, or amount of BSS used between the 2 systems (P >.05). However, for high-density cataracts, the 1.8 mm group had a greater change between the initial incision size and the incision size after phacoemulsification (P = .019, nuclear opalescence [NO] NO3; P = .001, NO4), a longer phacoemulsification time (P = .013, NO3), greater mean CDE (P = .005, NO3; P = .001, NO4), and greater corneal endothelial cell loss (P = .003, NO4). Conclusions: Both systems were safe and effective in microcoaxial phacoemulsification. The 1.8 mm system performed better with cortical-type cataract and the 2.2 mm system, with high-density nuclear-type cataract. [Copyright &y& Elsevier]

Background: This study aims to assess the efficacy and safety of geonchildan, a Korean traditional herbal medicine, for patients with active rheumatoid arthritis (RA) and evaluate the feasibility of a large-scale confirmatory clinical trial.Methods/design: This is a randomized, double-blind, placebo-controlled, parallel two-arm pilot trial in Seoul, Korea. Altogether, 30 patients diagnosed with RA for at least 3 months and with a Disease Activity Score for 28 joints (DAS28) ≥ 3.2 will be enrolled. Participants are randomly assigned to one of two groups, the experimental group or the placebo group, in a 1:1 ratio and will make four scheduled visits. The participants will be administered geonchildan or a placebo three times per day for 12 weeks. The change in DAS28 will be examined as the primary efficacy outcome. The secondary efficacy outcomes include the proportion of patients achieving ACR20, ACR50, ACR70, and EULAR responses; the DAS28 sub-items; the consumption of medication; Korean Health Assessment Questionnaire scores; inflammatory parameters; and the Korean medical diagnostic pattern indicator. Adverse events and laboratory test results will be recorded to evaluate safety. The process, resources used, and management of the study will also be assessed to determine the feasibility of a large-scale trial.Discussion: This is the first clinical trial to explore the efficacy and safety of geonchildan in patients with active RA. If the superiority of geonchildan versus the placebo is demonstrated and the study design is feasible, this study could form the foundation for a large-scale clinical trial. The results will be published in a peer-reviewed journal.Trial Registration: Clinical Research Information Service, KCT0001943 . Registered on 14 June 2016. [ABSTRACT FROM AUTHOR]

The first global workshop on implementation of the WHO guidelines on procedures and data requirements for changes to approved biotherapeutic products adopted by the WHO Expert Committee in 2018 was held in June 2019. The workshop participants recognized that the principles based on sound science and the potential for risk, as described in the WHO Guidelines on post-approval changes, which constitute the global standard for product life-cycle management are providing clarity and helping national regulatory authorities in establishing guidance while improving time-lines for an efficient regulation of products. Consequently, the regulatory situation for post-approval changes and guideline implementation is changing but there is a disparity between different countries. While the guidelines are gradually being implemented in some countries and also being considered in other countries, the need for regional workshops and further training on post-approval changes was a common theme reiterated by many participants. Given the complexities relating to post-approval changes in different regions/countries, there was a clear understanding among all participants that an efficient approach for product life-cycle management at a national level is needed to ensure faster availability of high standard, safe and efficacious medicines to patients as per the World Health Assembly Resolution 67.21. • WHO Guidelines constitute the global standard for product life-cycle management. • The Guidelines provide principles based on sound science and potential for risk. • The Guidelines help regulatory authorities in establishing national guidance. • Efficient approach for product life-cycle management at a national level is needed. [ABSTRACT FROM AUTHOR]