• Structural Engineering and Mechanics
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• 제64권5호
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• pp.661-670
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• 2017

The dynamic model test of dam-reservoir coupling system for a 203m high gravity dam is performed to investigate effects of reservoir water on dynamic responses of dam during earthquake. The hydrodynamic pressure under condition of full reservoir, natural frequencies and acceleration amplification factors along the dam height under conditions of full and empty reservoir are obtained from the test. The results indicate that the reservoir water have a stronger influence on the dynamic responses of dam. The measured natural frequency of the dam model under full reservoir is 21.7% lower than that of empty reservoir, and the acceleration amplification factor at dam crest under full reservoir is 18% larger than that under empty reservoir. Seismic dynamic analysis of the gravity dams with five different heights is performed with the Fluid-Structure Coupling Model (FSCM). The hydrodynamic pressures from Westergaard formula are overestimated in the lower part of the dam body and underestimated in its upper part to compare with those from the FSCM. The underestimation and overestimation are more significance with the increase of the dam height. The position of the maximum hydrodynamic pressure from the FSCM is raised with the increase of dam height. In view of the above, the Westergaard formula is modified with consideration in the influence of the height of dam, the elasticity of dam on the hydrodynamic pressure. The solutions of modified Westergaard formula are quite coincident with the hydrodynamic pressures in the model test and the previous report.

• Geomechanics and Engineering
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• 제20권2호
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• pp.87-101
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• 2020

The construction of combined pile-raft foundations is considered as the main option in designing foundations in high-rise buildings, especially in soils close to the ground surface which do not have sufficient bearing capacity to withstand building loads. This paper deals with the geotechnical report of the Northern Fereshteh area of Tabriz, Iran, and compares the characteristics of the single pile foundation with the two foundations of pile group and geogrid. Besides, we investigate the effects of five principal parameters including pile diameter and length, the number of geogrid layers, the depth of groundwater level, and pore water pressure on vertical consolidation settlement and pore water pressure changes over a year. This study assessed the mechanism of the failure of the soil under the foundation using numerical analysis as well. Numerical analysis was performed using the two-dimensional finite element PLAXIS software. The results of fifty-four models indicate that the diameter of the pile tip, either as a pile group or as a single pile, did not have a significant effect on the reduction of the consolidation settlement in the soil in the Northern Fereshteh Street region. The optimum length for the pile in the Northern Fereshteh area is 12 meters, which is economically feasible. In addition, the construction of four-layered ten-meter-long geogrids at intervals of 1 meter beneath the deep foundation had a significant preventive impact on the consolidation settlement in clayey soils.

• Structural Engineering and Mechanics
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• 제66권2호
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• pp.203-215
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• 2018

A large body of experiments have been conducted to date to evaluate the punching shear strength of flat slab-column connections, but it is noted that only a few of them have been considered for the development of the ACI Code provisions. The limited test results used for the development of the code provisions fall short of predicting accurately the punching shear strength of such connections. In an effort to address this shortfall and to gain an insight into the factors that control the punching shear strength of flat slab-column connections, we report a qualified database of 650 punching shear test results in this article. All slabs examined in this database were tested under gravity loading and do not contain shear reinforcement. In order to justify including any test result for evaluation punching shear database, we have developed an approved set of criteria. Carefully established set of criteria represent the actual characteristics of structures that include minimum compressive strength, effective depths of slab, flexural and compression reinforcement ratio and column size. The key parameters that significantly affect the punching shear strength of flat slab-column connections are then examined using ACI 318-14 expression. The results reported here have paramount significance on the range of applicability of the ACI Code provision and seem to indicate that the ACI provisions do not sufficiently capture many trends identified through regression of the principal parameters, and fall on the unsafe side for the prediction of the punching shear strength of flat slab-column connections.

• Smart Structures and Systems
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• 제6권3호
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• pp.225-238
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• 2010

We report on the development of a new technology for the fabrication of Micro-Electro-Mechanical-System (MEMS) strain sensors to realize a novel type of crackmeter for health monitoring of ageing civil infrastructures. The fabrication of micromachined silicon MEMS sensors based on a Silicon On Insulator (SOI) technology, designed according to a Double Ended Tuning Fork (DETF) geometry is presented, using a novel process which includes a gap narrowing procedure suitable to fabricate sensors with low motional resistance. In order to employ these sensors for crack monitoring, techniques suited for bonding the MEMS sensors on a steel surface ensuring good strain transfer from steel to silicon and a packaging technique for the bonded sensors are proposed, conceived for realizing a low-power crackmeter for ageing infrastructure monitoring. Moreover, the design of a possible crackmeter geometry suited for detection of crack contraction and expansion with a resolution of $10{\mu}m$ and very low power consumption requirements (potentially suitable for wireless operation) is presented. In these sensors, the small crackmeter range for the first field use is related to long-term observation on existing cracks in underground tunnel test sections.

• 호스피스학술지
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• 제2권2호
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• pp.1-16
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• 2002

Hospice can not only help the dying persons to maintain the high quality of life and facing the death in comfortable and peaceful state, but also the bereaved family to relieve the grief and sufferings. We investigated the work of hospice performed by church base from March 2000 until recently and reported the results dividing them into three parts. 1)The application of resources in church to administration, education, nursing delivery of hospice in the aspects of management. 2)Spiritual and postmortal management relating hospice nursing and funeral in hospice practice. 3)Case report of hospice and the patients situation(5 in average a month). The expected effects of hospice practice using the resources in church are as follows. 1)Hospice practice can provide the highly qualified persons with the opportunities to do voluntary services and find their lives worth living. Consequently hospice contributes to the spreading of the volunteering culture. 2)The volunteers in hospice can grow mature spiritually and get interpersonal relationships among the volunteers. Doyle. D., Geoflrey.W.C., & Macdonald. N.(1988). Oxford Textbook of Palliative Medicine(2nd ed). New York :Oxford University Press. Woodruff. R.(1996). Palliative Medicine(2nd ed). Melburn: Asperula Pty Ltd. 3)Through the hospice activity, church can practice and show the moral. 4)The volunteers in hospice can make a organization with a hope to be a beautiful community in church. 5)The patients and their families can enjoy the high quality of life through the holistic care provided by 33 nursing practical items of hospice. 6)'Hospice newsletter' can be a useful vehicle to provide readers with hope and encouragement through the stories of the patient and the volunteers. The persons unaware of the hospice can be contacted with hospice by this 'Hospice newsletter'. 7)Irrespective of the economic status, all patients are served equally that hospice can contribute to dying with dignity and the equality of human being.

• 한국병원경영학회지
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• 제25권3호
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• pp.38-52
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• 2020

Purpose: The purpose of the study is to suggest the main functions and implications of public hospitals to effectively respond to the future epidemic crisis based on analyzing the accessibility to designated Coronavirus Disease 2019 (COVID-19) medical institutions of Seoul and examining the main features of the quarantine of Seoul municipal hospitals. Method: To analyze the response and function of Seoul municipal hospitals, we reviewed the Infectious Disease Control and Prevention ACT, 258 articles of Seoul Metropolitan Government press releases from January to the end of April, 48 articles of Seoul Metropolitan Government's daily newsletters, 2019 Health Bureau Budget report. We also referred to internal data of Seoul Children's Hospital, Seoul Seobuk Hospital, and Seoul Eunpyeong Hospital during the same period. Besides, the accessibility to medical institutions was analyzed by using the COVID-19 data which was announced daily basis. Results: The accessibility of COVID-19 patients living in the Southeastern part of Seoul to a medical institutions was 16.2km on a distance basis, and it was the lowest accessibility among four regions of Seoul since it took about 40 minutes by car. On the other hand, patients living in the Northeast part had the highest accessibility, as the access to medical institutions was 10.7km and 27 minutes by car. Also, the main functions of the municipal hospital of Seoul against COVID-19 were to shift the public hospital function to COVID-19 patients only hospitals, to perform the epidemiological investigation by medical doctors, and to support the operation of self-isolation facilities, community treatment centers and triage rooms of community health centers. Conclusion: Through the experience of COVID-19, we suggested that the functions of public hospitals will be reorganized as the reinforcement of infectious disease treatment and mental health for quarantined patients, cooperation with private hospitals, supporting for strengthening community health capacity and preparation for another epidemic.

• Smart Structures and Systems
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• 제22권4호
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• pp.433-440
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• 2018

Pavements porous concrete is a noble structure design in the urban management development generally enabling water to be permeated within its structure. It has also capable in the same time to cater dynamic loading. During the technology development, the quality and quantity of waste materials have led to a waste disposal crisis. Using recycled materials (secondary) instead of virgin ones (primary) have reduced landfill pressure and extraction demanding. This study has reviewed the waste materials (Recycled crushed glass (RCG), Steel slag, Steel fiber, Tires, Plastics, Recycled asphalt) used in the pavement porous concretes and report their respective mechanical, durability and permeability functions. Waste material usage in the partial cement replacement will cause the concrete production cost to be reduced; also, the concretes' mechanical features have slightly affected to eliminate the disposal waste materials defects and to use cement in Portland cement (PC) production. While the cement has been replaced by different industrial wastes, the compressive strength, flexural strength, split tensile strength and different PC permeability mixes have depended on the waste materials' type applied in PC production.

• Earthquakes and Structures
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• 제8권3호
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• pp.761-778
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• 2015

The objective of this paper is to report the result of an experimental program conducted on the strengthening of nonductile RC frames by using external mesh reinforcement and plaster application. The main objective was to test an alternative strengthening technique for reinforced concrete buildings, which could be applied with minimum disturbance to the occupants. Generic specimen is two floors and one bay RC frame in 1/2 scales. The basic aim of tested strengthening techniques is to upgrade strength, ductility and stiffness of the member and/or the structural system. Six specimens, two of which were reference specimens and the remaining four of which had deficient steel detailing and poor concrete quality were strengthened and tested in an experimental program under cyclic loading. The parameters of the experimental study are mesh reinforcement ratio and plaster thickness of the infilled wall. The effects of the mesh reinforced plaster application for strengthening on behavior, strength, stiffness, failure mode and ductility of the specimens were investigated. Premature and unexpected failure mode has been observed at first and second specimens failed due to inadequate plaster thickness. Also third strengthened specimen failed due to inadequate lap splice of the external mesh reinforcement. The last modified specimen behaved satisfactorily with higher ultimate load carrying capacity. Externally reinforced infill wall composites improve seismic behavior by increasing lateral strength, lateral stiffness, and energy dissipation capacity of reinforced concrete buildings, and limit both structural and nonstructural damages caused by earthquakes.

• 한국의상디자인학회지
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• 제9권3호
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• pp.59-73
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• 2007

The purpose of this study is to find out the promotion methods for successful management of 'the fashion saho internet shopping mall' with a small capital. This study analyze the research reports, the news items, the documents on the internet shopping mall and data on promotion method which are offered by the hosting companies of the internet shopping mall like 'Cafe 24', 'Make shop', 'Whoismall' and the promotion consulting companies like 'Whoisad', 'Naver keyword shop'. And also analyze the data that interviewed the administrator of internet shopping mall and directly observed the famous internet shopping mall sites. Generally speaking, the promotion mix, marketing communication program can classify 'advertisement', 'publicity', 'personal selling', and 'sales promotion'. This study analyze the research materials on the basis of advertisement, publicity, personal selling, and sales promotion. The result are as follows. 1. The promotion methods at the stage of information the shopping mall site to the consumer are advertisement, and publicity. ${\bigcirc}$ The methods of advertisement are 'searching engine registration', 'advertisement of key word', 'advertisement of overture', 'advertisement of banner', 'advertisement cooperation marketing', 'advertisement of e-mail'. ${\bigcirc}$ The methods of publicity are using 'cafe', 'blog', 'Naver information site', 'community bulletin board', 'the fashion magazine or a press report' and 'cosponsorship'. 2. The main promotion methods at the stage of inducing the purchase are 'personal selling', and various 'sales promotion'. ${\bigcirc}$ 'Personal selling' at the shopping mall have an effect on the communication at bulletin board over the internet and the telephone. ${\bigcirc}$ 'Sales promotion' are attempted by 'VMD', 'deposit system', 'sale', etc.

• 한국건축시공학회지
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• 제18권3호
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• pp.305-312
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• 2018

This study is about the development of a non-sintered binder (NSB) which does not require a sintering process by using the industrial by-products Phosphogypsum (PG), Waste Lime (WL) and Granulated Blast Furnace Slag (GBFS). In this report, through SEM analysis of the NSB paste hardening body, micropore analysis of paste using the mercury press-in method and microstructure observation were executed to consider the influence of the formation of the pore structure and the distribution of pore volume on strength, and the following conclusions were reached. 1) Pore structure of NSB paste of early age is influenced by hydrate generation amount by GBFS and activator. 2) Through observing the internal microstructure of NSB binder paste, it was found that the strength expression at early age due to hydration reaction was achieved with a large amount of ettringite serving as the frame with C-S-H gel generated at the same time. It was confirmed that C-S-H gel wrapped around ettringite, and as time passed, the amount generated continually increased, and C-S-H gel tightly filled the pores of hardened paste, forming a dense network-type web structure. 3) For NSB-type cement, the degree of formation of gel pores below $10{\mu}m$ had a greater influence on strength improvement than simple pore reduction by charging capillary pores, and the pore size that had the greatest effect on strength was micropores with diameter below $10{\mu}m$.