• Wind and Structures
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• v.34 no.6
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• pp.469-482
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• 2022

The generalized extreme value distribution (GEVD) is frequently used to fit the block maximum of environmental parameters such as the annual maximum wind speed. There are several methods for estimating the parameters of the GEV distribution, including the least-squares method (LSM). However, the application of the LSM with the expected order statistics has not been reported. This study fills this gap by proposing a fitting method based on the expected order statistics. The study also proposes a plotting position to approximate the expected order statistics; the proposed plotting position depends on the distribution shape parameter. The use of this approximation for distribution fitting is carried out. Simulation analysis results indicate that the developed fitting procedure based on the expected order statistics or its approximation for GEVD is effective for estimating the distribution parameters and quantiles. The values of the probability plotting correlation coefficient that may be used to test the distributional hypothesis are calculated and presented. The developed fitting method is applied to extreme thunderstorm and non-thunderstorm winds for several major cities in Canada. Also, the implication of using the GEVD and Gumbel distribution to model the extreme wind speed on the structural reliability is presented and elaborated.

• Safety and Health at Work
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• v.8 no.3
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• pp.258-266
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• 2017

Background: Welders are exposed to many known and suspected carcinogens. An excess lung cancer risk among welders is well established, but whether this is attributable to welding fumes is unclear. Excess risks of other cancers have been suggested, but not established. We investigated welding cancer risks in the population-based Canadian Census Health and Environmental Cohort. Methods: Among 1.1 million male workers, 12,845 welders were identified using Standard Occupational Classification codes and followed through retrospective linkage of 1991 Canadian Long Form Census and Canadian Cancer Registry (1992-2010) records. Hazard ratios (HRs) were calculated using Cox proportional hazards models based on estimated risks of lung cancer, mesothelioma, and nasal, brain, stomach, kidney, and bladder cancers, and ocular melanoma. Lung cancer histological subtypes and risks by industry group and for occasional welders were examined. Some analyses restricted comparisons to blue-collar workers to minimize effects of potential confounders. Results: Among welders, elevated risks were observed for lung cancer [HR: 1.16, 95% confidence interval (CI): 1.03-1.31], mesothelioma (HR: 1.78, 95% CI: 1.01-3.18), bladder cancer (HR: 1.40, 95% CI: 1.15-1.70), and kidney cancer (HR: 1.30, 95% CI: 1.01-1.67). When restricted to blue-collar workers, lung cancer and mesothelioma risks were attenuated, while bladder and kidney cancer risks increased. Conclusion: Excess risks of lung cancer and mesothelioma may be partly attributable to factors including smoking and asbestos. Welding-specific exposures may increase bladder and kidney cancer risks, and particular sources of exposure should be investigated. Studies that are able to disentangle welding effects from smoking and asbestos exposure are needed.

• Journal of The Korean Association For Science Education
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• v.37 no.1
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• pp.215-223
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• 2017

This study aims to find an effective way to present essential science concepts in national science curriculum through international comparisons. Next Generation Science Standard (US), Ontario Science Curriculum (Canada), Australia Science Curriculum, and British/English Science Curriculum were selected for comparison. In science curriculum documents, these countries used terms such as 'Key ideas,' 'Big ideas,' 'Key concepts,' 'Disciplinary core ideas.' and 'Fundamental concepts' to present essential concepts of science. This study reviewed the characteristics of the meaning, the status, and the role of essential concepts country by country. The result shows essential concepts have been used with different meanings and statutes in each case. Furthermore, various roles were performed through essential concepts in order to organize their science curriculum. From these foreign nation's cases, this study proposes several ways to present essential science concepts based on results. First, interdisciplinary integrated concepts were needed to organize an integrated science curriculum. In science curriculum documents of the United States, Canada, Australia and England, two types of terms were used in order to structuralize an integrated science curriculum. Second, essential concepts should include concepts related with function and value as well as scientific knowledge. Third, essential concepts need to be presented in such a way as to show specific contexts. Therefore, selecting appropriate contents and structure are needed to be able to improve the way to present essential concepts in Korea's educational environment.

• Wind and Structures
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• v.11 no.3
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• pp.193-208
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• 2008

This paper focuses on assessing the failure of one of the transmission towers that collapsed in Winnipeg, Canada, as a result of a microburst event. The study is conducted using a fluid-structure numerical model that was developed in-house. A major challenge in microburst-related problems is that the forces acting on a structure vary with the microburst parameters including the descending jet velocity, the diameter of the event and the relative location between the structure and the jet. The numerical model, which combines wind field data for microbursts together with a non-linear finite element formulation, is capable of predicting the progressive failure of a tower that initiates after one of its member reaches its capacity. The model is employed first to determine the microburst parameters that are likely to initiate failure of a number of critical members of the tower. Progressive failure analysis of the tower is then conducted by applying the loads associated with those critical configurations. The analysis predicts a collapse of the conductors cross-arm under a microburst reference velocity that is almost equal to the corresponding value for normal wind load that was used in the design of the structure. A similarity between the predicted modes of failure and the post event field observations was shown.

• Water Engineering Research
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• v.2 no.3
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• pp.179-185
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• 2001

The time consuming and expensive nature of experimental research on scouring processes caused by flowing water makes it attractive to develop numerical tools for the predication of the interaction of the fluid flow and the movable bed. In this paper the numerical simulation of scour by a wall jet is presented. The flow is assumed to be two-dimensional, and the alluvium is cohesionless. The solution process, repeated at each time step, involves simulation of a turbulent wall jet flow, solution of the convection-diffusion of sand concentration, and prediction of the bed deformation. For simulation of the jet flow, the governing equations for momentum, mass balance and turbulent parameters are solved by the finite volume method. The SIMPLE scheme with momentum interpolation is used for pressure correction. The convection-diffusion equation is solved for sediment concentration. A boundary condition for concentration at the bed, which takes into account the effect of bed-load, is implemented. The time rate of deposition and scour at the bed is obtained by solving the continuity equation for sediment. The shape and position of the scour hole and deposition of the bed material downstream of the hole appear realistic.

• Journal of the Economic Geographical Society of Korea
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• v.10 no.3
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• pp.263-280
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• 2007

Recently, many cities and regions of the world attempt to promote cultural and arts activities in order to vitalize regional economies and strengthen local identity. Some old industrial cities of the advanced economies in particular often introduce cultural and arts activities in renovating obsolete urban infra-structure, revitalize urban economy, clean polluted urban environment, and advertise various development projects. A small Canadian city, Stratford, Ontario, has shown a spectacular success in such efforts. By hosting Shakespearian festivals every year since 1953, the theatre company, the Shakespearian Festival of Canada in Stratford, sells about 600 thousands tickets, attracting 2 million visitors to the area. With the festivals, the city became able to host a large cultural cluster composed of the theatre company, chef school, summer music festival, and Chicago Associates. The city has also able to maintain one of the most competent theatre companies in the North America.

• Journal of the Economic Geographical Society of Korea
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• v.12 no.3
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• pp.260-276
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• 2009

Niagara Region in Canada is located in the Northeast industrial area of North America which experienced severe de-industrialization since the 1960s. Since the climate there is very cold in winter time, agricultural activities can not be well practiced. However, this area became well-known to the world with the IceWine industry. This paper introduces and analyses how this became possible to find out factors contributing to the success and draw implications to other regions. Based on case studies on wineries, this paper concludes key factors of the success as innovative activities of founding fathers of leading wineries and cooperations among governments, universities, and wineries of the region.

• Journal of Chest Surgery
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• v.56 no.6
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• pp.420-430
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• 2023

Background: This study provides an update to a landmark 2004 report describing demographics, training, and trends in adherence to thoracic surgery practice standards in Canada. Methods: An updated questionnaire was administered to all members of the Canadian Association of Thoracic Surgeons via email (n=142, compared to n=68 in 2004). Our report incorporates internal data from Ontario Health and the Canadian Partnership Against Cancer. Results: Forty-eight surgeons completed the survey (male, 70.8%; mean±standard deviation age, 50.3±9.3 years). This represents a 33.8% response rate, compared to 64.7% in 2004. Most surgeons (69%) served a patient population of over 1 million per center; 32%-34% reported an on-call ratio of 1:4-1:5 days, and the average weekly hours worked was 56.4±11.9. Greater access to dedicated geographic units per center (73% in 2021 vs. 53% in 2004) has improved thoracic-associated services and house staff, notably endoscopy units (100% vs. 91%), with 73% of respondents having access to both endobronchial and endoscopic ultrasound. Access to thoracic radiology has also improved, particularly regarding positron emission tomography scanners per center (76.9% vs. 13%). Annual case volumes for lung (255 vs. 128), esophageal (41 vs. 19), and mediastinal resections (30 vs. 13), along with hiatal hernia repair (45 vs. 20), have increased substantially despite reports of operating room availability and radiology as rate-limiting steps. Conclusion: This survey characterizes compliance with current practice standards, addressing the needs of thoracic surgeons across Canada. Over 85% of respondents were aware of the 2004 compliance paper, and 35% had applied for resources and equipment in response.

• Membrane Journal
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• v.3 no.1
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• pp.35-39
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• 1993

Reverse osmosis(RO) and pervaporation(PV) membrane separation proceaes were compared with each other experimentally for the system of water-ethanol mixtures by using nylon 4 blended membranes. The separation effciencies of PV were better than those of RO as expected in previous paper covering the theoretical comparisons of both processes, however tbe permeabilities data showed erraerie results due to the membrane imperfections.

• Proceedings of the Membrane Society of Korea Conference
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• 1997.06a
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• pp.143-158
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• 1997

Electrochemical deionization (EDI) offers continuous demineralization at higher water recovery rates (>90%), compared with mixed bed ion exchange, and without the use of chemical regenerants and the associated production of saline waste water. Although EDI technology has been used in some power generation applications, its wider application requires the satisfactory resolution of outstanding capital cost and performance issues. This paper reports on the field evaluation of a new cost-effective EDI technology in a power generation application. The E-Cell System$^{TM}$, which became commercially available in the fourth quarter of 1996, consists of a rugged, modular system, based on a new high-performance EDI stack. Starting in May 1996, a 100 gpm modular EDI pilot system, rated for operation at 100 psi, was evaluated at the TVA Brown's Ferry Nuclear Plant. The feed consisted of Reverse Osmosis (RO) permeate with a conductivity of 4-7 $\mu$S/cm. The pilot system reliably produced 17.8-18.0 M$\Omega$.cm water under design operating conditions, independent. Silica levels were reduced from ca. 50 ppb to 4 ppb, while TOC levels were reduced from ca. 120 ppb to 30 ppb.