• Coupled systems mechanics
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• v.9 no.4
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• pp.311-323
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• 2020

This paper deals with the effect of the mode shapes on the dynamic response of a multi-storey frame subjected to moving train loads which are modelled as loads of constant intervals with constant velocity using the finite element method. The multi-storey frame is modelled as a number of Bernoulli-Euler beam elements. First, the first few modes of the multi-storey frame are determined. Then, the effects of force span length to beam length ratio and velocity on dynamic magnification factor (DMF) are evaluated via 3D velocity-force span length to beam length ratio-DMF graphics and its 2D projections. By using 3D and 2D graphics, the directions of critical speeds that force the structure under resonance conditions are determined. Last, the mode shapes related to these directions are determined by the time history and frequency response graphs. This study has been limited by the vibration of the frame in the vertical direction.

• The Journal of the Acoustical Society of Korea
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• v.16 no.2E
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• pp.21-26
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• 1997

We propose to use transverse waves instead of longitudinal waves in a scanning tomographic acoustic microscope (STAM) and new type of multiple-transducer with the functions of muliple-angle and multiple-frequency tomography. Proposed multiple-transducer scheme has three insonification angles and three resonance frequencies in order to operate in the transverse wave mode and multiple-angle and multiple frequency tomography for the STAM. In order to evaluate the performance of proposed transducer scheme we have simulated tomographic reconstruction with back-and-forth propagation(BFP) algorithm. Simulation results showed proposed multiple-transducer scheme is capable of obtaining good resolution with transverse wave mode and multiple-frequency tomography. It is also showed that proposed scheme is an efficient rotation scheme by proportion to the number of projections.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1798-1803
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• 2003

Surface and edge finishing processes are important technological operations of in parts machining. Quality of the finished parts directly affect the performance of the whole product. Especially, edge quality, which depends on burr control, is extremely important. Burrs are undesirable projections of the material beyond the edge of the workpiece. A number of deburring processes have been developed such as barreling, brushing, chemical methods etc. But, there are only few publications in the area of applying ultrasonics to deburring. When ultrasonic vibration propagates in the liquid medium, a large number of bubbles are formed. These bubbles generate an extremely strong force, which can be used to remove burrs. Cavitation is used as a term to describe the erosion of parts caused by the action of cavities in liquid. The object of this study is to analyze the effects of ultrasonic cavitation in the deburring process. For this purpose, we introduce a new ultrasonic cavitation method, which efficiently removes the burrs. Experimental parameters to verify the deburring effects of ultrasonic cavitations are ultrasonic power, amplitude, distant of the transducer from the workpiece, deburring time and abrasive. It has been shown that deburring with ultrasonic cavitation in water is effective to burrs.

• Journal of the Korean Operations Research and Management Science Society
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• v.42 no.1
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• pp.29-41
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• 2017

Korea is expected to become a super-aged society by 2050. Given an aging population and the increasing pressure for the early retirement, a sufficient social safety net for elderly population becomes important. The Korean government introduced public reverse mortgage program in 2007, which is a product for aging seniors and the elderly, The number of reverse mortgage subscribers has also steadily grown. The demand continues to grow, but the reverse mortgage over a long period of time is a highly uncertain and risky product in the position of guarantee or lending institution. Thus, suitable demand prediction of the reverse mortgage subscribers is necessary for stable and sustainable operation. This study uses a Bass diffusion model to forecast the long-term demand for reverse mortgage and provides insight into reverse mortgage by forecasting demand for stability and substantiality of the loan product. We represent the projections of new subscribers on the basis of the data obtained from Korea Housing Finance Corporation. Results show that potential market size of Korean reverse mortgage reaches approximately 760,000-1,160,000 households by 2020. We validate the results by comparing the estimate of the cumulative number of subscribers with that found in literature.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1848-1852
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• 2003

Generally, burrs refer to projected parts remained on the edge after material had been processed. These burrs decrease the precision of part and cause many problems in part assembly. Burrs are undesirable projections of the material beyond the edge of the workpiece. A number of deburring processes have been developed such as barreling, brushing, chemical methods etc. But, there are a few publications in the area of applying ultrasonics to deburring. When ultrasonic vibration propagates in the liquid medium, a large number of bubbles are formed. These bubbles generate an extremely strong force, which removes burrs. Cavitations were used as a term to describe erosion of parts caused by the action of cavities in liquid. The object of this study is to analyze the effects of ultrasonic cavitation in deburring process. For this purpose, we introduce a new ultrasonic cavitation method with abrasive, which efficiently removes the burrs. Experimental parameters to verify the deburring effects of ultrasonic cavitations are ultrasonic power, amplitude, distant of the transducer from the workpiece, deburring time and abrasive. It has been shown that deburring with ultrasonic cavitation in water is effective to burrs.

• Journal of Families and Better Life
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• v.21 no.3
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• pp.39-46
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• 2003

There are three main purposes in this study. First, we project the number of elderly dementia population in the future based on the projection of the elderly population in the Kyungpook area. Second, the demands of home-based care service and facility-based care for the elderly dementia are estimated. Thirdly, some policy implications for the improvement of welfare services for the elderly dementia are addressed. The findings of this study are as follows. Considering the size of the elderly dementia population, facilities for the elderly dementia are extremely insufficient and most of the elderly dementia patients rely heavily on home-based care. Although we expect that there will be a rapid increase in the number of the elderly dementia in the next two decades, the social welfare services for them in the future are very unreliable. Home nursing for the demented elderly needs to be recognized by law and financed by the government. In this context, we address some issues regarding the rapid growth of the elderly dementia population in the future and social welfare services for them as well. Finally we suggest some policy implications regarding this matter.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.4379-4386
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• 2013

Projection of cancer incidence is essential for planning cancer control actions, health care and allocation of resources. Here we project the cancer burden at the National and State level to understand the magnitude of cancer problem for the various calendar years from 2011 to 2026 at 5-yearly intervals. The age, sex and site-wise cancer incidence data along with populations covered by the registries were obtained from the report of National Cancer Registry Programme published by Indian Council of Medical Research for the period 2001-2004. Pooled age sex specific cancer incidence rates were obtained by taking weighted averages of these seventeen registries with respective registry populations as weights. The pooled incidence rates were assumed to represent the country's incidence rates. Populations of the country according to age and sex exposed to the risk of development of cancer in different calendar years were obtained from the report of Registrar General of India providing population projections for the country for the years from 2001 to 2026. Population forecasts were combined with the pooled incidence rates to estimate the projected number of cancer cases by age, sex and site of cancer at various 5-yearly periods Viz. 2011, 2016, 2021 and 2026. The projections were carried out for the various leading sites as well as for 'all sites' of cancer. In India, in 2011, nearly 1,193,000 new cancer cases were estimated; a higher load among females (603,500) than males (589,800) was noted. It is estimated that the total number of new cases in males will increased from 0.589 million in 2011 to 0.934 million by the year 2026. In females the new cases of cancer increased from 0.603 to 0.935 million. Three top most occurring cancers namely those of tobacco related cancers in both sexes, breast and cervical cancers in women account for over 50 to 60 percent of all cancers. When adjustments for increasing tobacco habits and increasing trends in many cancers are made, the estimates may further increase. The leading sites of cancers in males are lung, oesophagus, larynx, mouth, tongue and in females breast and cervix uteri. The main factors contributing to high burden of cancer over the years are increase in the population size as well as increase in proportion of elderly population, urbanization, and globalization. The cancer incidence results show an urgent need for strengthening and augmenting the existing diagnostic/treatment facilities, which are inadequate even to tackle the present load.

• Korea journal of population studies
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• v.33 no.2
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• pp.85-111
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• 2010

South Korea has experienced a rapid fertility decline and notable mortality improvement. As the drop in TFR was quicker and greater in terms of tempo and magnitude, it cast a new challenge of population projection - how to improve the forecasting accuracy in the country with a super-low fertility pattern. This study begin with the current status of the national population projection as implemented by Statistics Korea by comparing the 2009 interim projection with the 2006 official national population projection. Secondly, this study compare the population projection system including projection agencies, projection horizons, projection intervals, the number of projection scenarios, and the number of assumptions on fertility, mortality and international migration among super-low fertility countries. Thirdly we illustrate a stochastic population projection for Korea by transforming the population rates into one parameter series. Finally we describe the future challenges of the national population projection, and propose the projection scenarios for the 2011 official population projection. To enhance the accuracy, we suggest that Statistics Korea should update population projections more frequently or distinguish them into short-term and long-term projections. Adding more than four projection scenarios including additional types of "low-variant"fertility could show a variety of future changes. We also expect Statistics Korea topay more attention to the determination of a base population that should include both national and non-national populations. Finally we hope that Statistics Korea will find a wise way to incorporate the ideas underlying the system of stochastic population projection as part of the official national population projection.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.462-462
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• 2022

Wetlands are one of the most vital natural habitats on the planet. India is incredibly blessed to have a number of multifunctional wetland ecosystems. Wetlands, in addition to their functional importance, can act as sources or sinks for greenhouse gases (GHGs) depending on their intrinsic factors. Carbon (CO2) and Methane (CH4) are the major greenhouse gases (GHG's) emitted in wetlands. It is demonstrated that, despite having 4.6 percent of its area covered by natural or man-made wetlands, being home to a large number of wetlands, and being the world's second largest cultivator of paddy, India's wetlands, including paddy fields that are intermittently flooded as typical wetlands, have been very poorly studied in terms of GHG emissions. The purpose of this paper is to examine the status of Indian wetlands and wetlands in terms of CH4 and CO2 emissions. The present study also reviews various literature to provide the equations, parameters that are required for estimating carbon and methane and some of the best strategies for conserving carbon in wetlands. The findings suggest that both non-manipulative and manipulative measures can be used to improve Carbon Sequestration (CS). Non-manipulative measures aim to improve CS by increasing the spatial extent of wetlands, whereas manipulative measures aim to change the characteristics of specific wetland components that influence CS. Uncertainty in carbon dynamics projections under changing environmental conditions is caused by a number of Knowledge gaps: i) There is a lack of knowledge on how organic matter mineralizes and partitions into carbon dioxide, methane, and dissolved organic carbon, ii) With the notable exception of methane dynamics, models that represent the dynamic interaction of processes and their controls have yet to be established. As a result, more research is needed to fully understand the importance of wetlands in terms of GHG emissions and carbon sequestration in India.

• Archives of Plastic Surgery
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• v.50 no.6
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• pp.563-567
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• 2023

Ear keloids are challenging lesions to treat due to high recurrence rates postexcision. Conservative compression techniques as adjunct treatment have been reported to be effective. An innovative technique of using computer-aided design/computed-aided manufacturing to print a customized auricular splint improves efficiency and comfort level for patients compared with conventional methods. The ear is scanned using an intraoral scanning 2 weeks postsurgery. A two-piece auricular splint is designed on the digital model, incorporating perforated projections for three nylon screws for retention of the splint. The splint is printed with clear acrylic material, postprocessed, and finished. The patient is taught to assemble the components of the splint and instructed to wear for at least 8 hours daily. The surgery site reviewed for any ulceration, pain, or recurrence of keloid for 6 months. During the 6-month review, the excision scar remained flat and pink. The patient also reports unrestricted daily activities. The digital workflow increases comfort for the patient and reduces the number of hours required to produce a customized auricular splint compared with conventional methods. A fully digital workflow for a printed auricular splint should be considered for adjunctive treatment to excision of ear keloids.