• Journal of Korean Society of Transportation
• /
• v.24 no.7 s.93
• /
• pp.129-138
• /
• 2006

After Seoul has introduced semi-public bus management system(public management-private operation), the Seoul Metro Government needs a scientific management tool for optimal scheduling for bus routes, to reduce unnecessary operations and provide demand responsive service. As a product of this effort, this paper proposes a heuristic model that could minimize total passenger waiting time under the constraints, such as number of vehicles, working conditions, max load point, minimax headway. etc. For verifying the validity of the proposed model, it is applied to an existing bus route. It results that headways in rush hours become decreased and the passenger waiting time could be decreased. In conclusion. it is thought that the Proposed model contributes to efficiency of bus operation.

• Composites Research
• /
• v.17 no.5
• /
• pp.85-95
• /
• 2004

Other than in the fields of rolling stock and marine, in England, UK, Phenolic Composites (herein after, PCs) have been significantly utilized to fire protecting panels in construction, in particular, in architectures. In general, indeed, so-called "Plastic" or "Synthesized Resins" have been applied successfully in our societies all over the world, however, once, when ignited from somewhat reason, they burn much easily generating large amount of "SMOKE" from their nature of petroleum-borne materials as a matter of fact, people have forgotten about it. "SMOKE" caused many fire accidents horror tragedies as everyday people know today. The experts in this field such as PC engineers, researchers and others can take their responsibilities to explain it, persuade it and realize "Safer Environment for People" with well-experienced and technology innovated PCs. In this paper, the co-authors, collaborating UK and Japan, are making efforts to report how the PCs work good jobs to our societies showing some successful track records in construction or architecture fields in UK. How about on this matter in Japan\ulcorner "SMOKE fire" is always waiting fur us. We should stop smoking and SMOKE fire, in our public places.We should stop smoking and SMOKE fire, in our public places.

• Journal of Korea Spatial Information System Society
• /
• v.3 no.1 s.5
• /
• pp.75-87
• /
• 2001

The advantages of using components result from their reusability between applications. Applications can be easily implemented by adding components. In this paper, we described the design and implementation process of ASC(Application Service Component) for component-based GIS applications. In our project, there are 5 applications : Road Facility Management, Urban Planning, Cadastral Map Management, Water Supply Management, and Sewerage Management. All of them use MapBase component which supports common GIS functionality. Although they are different applications, some parts of them are same. We analyzed the developed results in 1st and 2nd year, and the achievement of UIS(Urban Information System) project in Busan Metro City in Korea. The UIS of Busan was consisted of 5 applications to equal with our project. Then, we extracted 11 common used components between 5 applications, and implemented 5 common components of them and 2 additional components. They were Authority, GISReport, IndexMap, Measurement, Search, Symbol Manager, and Attribute Display. As we offered them to companies developing application components, they were able to reduce the development time.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.39 no.5
• /
• pp.613-621
• /
• 2019

In general, transfer in subway stations is defined as transfer between lines and station transfer. In transfer between lines, passengers change from one subway line to another by utilizing horizontal pedestrian facilities such as transfer passages and pedestrian way. Station transfer appears in the situation that subway lines of enter and exit gate terminals differs from those of boarding and alighting trains and passenger trips utilize both vertical pedestrian facilities such as stair and escalator and horizontal facilities. The hypothesis on these two transfers presupposes that all subway lines are operated by either local train or express in subway network. This means that in a transfer case both local and express trains are operated in the same subway line, as a case of Seoul Metro Line 9, has not been studied. This research proposes a methodology of finding the same line transfer in the Seoul metropolitan subway network built based on the smart card network data by suggesting expanded network concept and a model that passengers choose a theirs minimum time routes.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.25 no.1
• /
• pp.61-69
• /
• 2022

Purpose: Studies in adults have shown an increasing incidence of Clostridioides difficile infection (CDI) in patients hospitalized with acute pancreatitis (AP). There is lack of epidemiological data on CDI and its impact on hospitalized pediatric patients with AP. Methods: We analyzed the National Inpatient Sample and Kids' Inpatient Database between the years 2003 and 2016 and included all patients (age <21 years) with a primary diagnosis of AP using specific International Classification of Diseases codes. We compared clinical outcomes between children with CDI and those without CDI. Our primary outcome was severe AP and secondary outcomes included length of stay and hospital charges. Results: A total of 123,240 hospitalizations related to AP were analyzed and CDI was noted in 0.6% of the hospital. The prevalence rate of CDI doubled from 0.4% (2003) to 0.8% (2016), p=0.03. AP patients with CDI had increased comorbidities, and also underwent more invasive surgical procedures, p<0.05. AP patients with CDI had a higher in-hospital mortality rate and increased prevalence of severe AP, p<0.001. Multivariate regression models showed that CDI was associated with 2.4 times (confidence interval [CI]: 1.91 to 3.01, p<0.001) increased odds of severe AP. CDI patients had 7.24 (CI: 6.81 to 7.67, p<0.001) additional hospital days while incurring $59,032 (CI: 54,050 to 64,014, p<0.001) additional hospitalization charges. Conclusion: CDI in pediatric patients with AP is associated with adverse clinical outcomes and increased healthcare resource utilization. Further studies are needed to elucidate this association to prevent the development of CDI and to improve outcomes.

• Clinical Endoscopy
• /
• v.56 no.1
• /
• pp.38-49
• /
• 2023

Background/Aims: Patients with Barrett's esophagus are at increased risk of developing esophageal adenocarcinoma. Endoscopic therapies aim to eradicate dysplastic and metaplastic tissues. Hybrid argon plasma coagulation (hybrid-APC) utilizes submucosal fluid injection to create a protective cushion prior to ablation that shields the submucosa from injury. We performed a pooled meta-analysis to evaluate the safety and efficacy of hybrid-APC. Methods: We conducted a systematic search of major electronic databases in April 2022. Studies that included patients with dysplastic and non-dysplastic Barrett's esophagus undergoing treatment with hybrid-APC were eligible for inclusion. Outcome measures included complete remission of intestinal metaplasia (CR-IM), stricture formation, serious adverse events, and number of sessions necessary to achieve CR-IM. Results: Overall pooled CR-IM rate for patients undergoing hybrid-APC was 90.8% (95% confidence interval [CI], 0.872-0.939; I²=0%). Pooled stricture rate was 2.0% (95% CI, 0.005-0.042; I²=0%). Overall serious adverse event rate was 2.7% (95% CI, 0.007-0.055; I²=0%). Conclusions: Results of the current meta-analysis suggest that hybrid-APC is associated with high rates of CR-IM and a favorable safety profile. Interpretation of these results is limited by the inclusion of retrospective cohort and case series data. Randomized controlled trials that standardize treatment and outcome evaluation protocols are necessary to understand how this treatment option is comparable to the current standards of care.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.14 no.1
• /
• pp.77-88
• /
• 2010

Wireless Mesh Networks are consist of mobility mesh clients and mesh routers. WMNs can communicate with heterogeneous networks such as IEEE 802.11, IEEE 802.15, IEEE 802.16 and sensor networks. WMNs which is based on ad hoc network are on research and developing to enhance WLANs, WPANs, or WMANs. WMNs can offer environment to serve human, service to person area, campus, and metro. But WMNs has many problems to solve about enhancing performance and generalization. Among them, Existing protocol layers has many problems enhancing to optimize WMNs. This document issues problems about WMNs in protocol layer and suggest the solutions. Also, suggests the requirements and the methods of QoS supporting issue.

• New & Renewable Energy
• /
• v.5 no.2
• /
• pp.15-24
• /
• 2009

As new small scale LFG (landfill gas) energy project model which can improve economic feasibility limited due to the economy of scale, LFG-Microturbine combined heat and power system with $CO_2$ fertilization into greenhouses was proposed and investigated including basic design process prior to the system installation at Gwang-ju metro sanitary landfill. The system features $CH_4$ enrichment for stable microturbine operation, reduction of compressor power consumption and low CO emission, and $CO_2$ supplement into greenhouse for enhancement plant growth. From many other researches, high $CO_2$ concentration was found to enhance $CO_2$ assimilation (also known as photosynthesis reaction) which converts $CO_2$ and $H_2O$ to sugar using light energy. For small scale landfills which produce LFG under $3\;m^3$/min, among currently available prime movers, microturbine is the most suitable power generation system and its low electric efficiency can be improved with heat recovery. Besides, since its exhaust gas contains very low level of harmful contaminants to plant growth such as NOx, CO and SOx, microturbine exhaust gas is a suitable and economically advantageous $CO_2$ source for $CO_2$ fertilization in greenhouse. The LFG-Microturbine combined heat and power generation system with $CO_2$ fertilization into greenhouse gas to enhance plant growth is technologically and economically feasible and improves economical feasibility compared to other small scale LFG energy project model.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.26 no.1
• /
• pp.23-33
• /
• 2023

Purpose: The incidence and prevalence of inflammatory bowel disease (IBD) are increasing along with an increasing number of patients with comorbid conditions like psychiatric and behavioral disorders, which are independent predictors of quality of life. Methods: Non-overlapping years (2003-2016) of National Inpatient Sample and Kids Inpatient Database were analyzed to include all IBD-related hospitalizations of patients less than 21 years of age. Patients were analyzed for a concomitant diagnosis of psychiatric/ behavioral disorders and were compared with IBD patients without psychiatric/behavioral disorder diagnoses for outcome variables: IBD severity, length of stay and inflation-adjusted hospitalization charges. Results: Total of 161,294 IBD-related hospitalizations were analyzed and the overall prevalence rate of any psychiatric and behavioral disorders was 15.7%. Prevalence rate increased from 11.3% (2003) to 20.6% (2016), p<0.001. Depression, substance use, and anxiety were the predominant psychiatric disorders. Regression analysis showed patients with severe IBD (odds ratio [OR], 1.57; confidence interval [CI], 1.47-1.67; p<0.001) and intermediate IBD (OR, 1.14; CI, 1.10-1.28, p<0.001) had increased risk of associated psychiatric and behavioral disorders than patients with a low severity IBD. Multivariate analysis showed that psychiatric and behavioral disorders had 1.17 (CI, 1.07-1.28; p<0.001) mean additional days of hospitalization and incurred additional $8473 (CI, 7,520-9,425; p<0.001) of mean hospitalization charges, independent of IBD severity. Conclusion: Prevalence of psychiatric and behavioral disorders in hospitalized pediatric IBD patients has been significantly increasing over the last two decades, and these disorders were independently associated with prolonged hospital stay, and higher total hospitalization charges.

• Journal of Gifted/Talented Education
• /
• v.19 no.3
• /
• pp.697-727
• /
• 2009

The purposes of this study are to investigate Korean science teachers' perception on the science gifted education in Korea, and to investigate if there are differences on their perception among the science teachers whose institutes are different. Their institutes are divided into three groups, which are the formal schools for the gifted in science such as Science High-School, gifted education centers attached to district education authority, and general secondary schools. For the study, 266 science teachers were sampled from the schools in Busan Metro-city, Ulsan Metro-city, and Kyoungnam Province, and then questionnaire developed by the authors were administered to them. The research results are as follows. Firstly, teachers who were going to participate in special education for the gifted in science answered affirmatively, and they thought it seemed worthwhile. On the other hand teachers who were not going to participate in it, answered negatively, mentioning shortage in specialty or extra work overload. Secondly, only the Korean Educational Development Institute was too much preferred by science teachers for teacher training institute for the gifted education in science. Therefore, it is needed to extend the teacher training institutes for the gifted education in science throughout the country. Thirdly, the perception of science teachers on the constitution of a class for the gifted in science is very different among the teachers of formal schools for the gifted in science and the teachers who teach science part time when it is needed in the district institutes for the gifted education. Finally, the perception on the aims of special education for the gifted in science is very different between the teachers who teach the gifted in science and the teachers who do not teach them.