• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.1
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• pp.18-28
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• 2001

The present study investigates flow dynamics between two dimensional compliant plates under sinusoidal flow conditions in order to understand influence of wall motion, impedance phase angle (time delay between pressure and flow waveforms), and non-Newtonian fluid on wall shear stress using computational fluid dynamics. The results showed that wall motion induced additional terms in the streamwise velocity profile and the pressure gradient. These additional terms due to wall motion reduced the amplitude of wall shear stress and also changed the mean wall shear stress. The trend of the changes was very different depending on the impedance phase angle. As the impedance phase angle was changed to more negative values, the mean wall shear stress decreased while the amplitude of wall shear stress increased. As the phase angle was reduced from 0°to -90°under $\pm$4% wall motion, the mean wall shear stress decreased by 12% and the amplitude of wall shear stress increased by 9%. Therefore, for hypertensive patients who have large negative phase angles, the ratio of amplitude and mean of the wall shear stress is raised resulting in a more vulnerable state to atherosclerosis according to the low and oscillatory shear stress theory. We also found that non-Newtonian characteristics of the blood protect atherosclerosis by decreasing the oscillatory shear index.

• Journal of the Earthquake Engineering Society of Korea
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• v.28 no.2
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• pp.85-92
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• 2024

This study presents code-compliant seismic details by addressing dry mechanical splices for precast concrete (PC) beam-column connections in the ACI 318-19 code. To this end, critical observations of previous test results on precast beam-column connection specimens with the proposed seismic detail are briefly reported in this study, along with a typical reinforced concrete (RC) monolithic connection. On this basis, nonlinear dynamic models were developed to verify seismic responses of the PC emulative moment-resisting frame systems. As the current design code allows only the emulative design approach, this study aims at identifying the seismic performances of PC moment frame systems depending on their emulative levels, for which two extreme cases were intentionally chosen as the non-emulative (unbonded self-centering with marginal energy dissipation) and fully-emulative connection details. Their corresponding hysteresis models were set by using commercial finite element analysis software. According to the current seismic design provisions, a typical five-story building was designed as a target PC building. Subsequently, nonlinear dynamic time history analyses were performed with seven ground motions to investigate the impact of emulation level or hysteresis models (i.e., energy dissipation performance) on system responses between the emulative and non-emulative PC moment frames. The analytical results showed that both the base shear and story drift ratio were substantially reduced in the emulative system compared to that of the non-emulative one, and it indicates the importance of the code-compliant (i.e., emulative) connection details on the seismic performance of the precast building.

• Journal of IKEEE
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• v.23 no.2
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• pp.370-374
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• 2019

It was found that temperature and humidity did not affect the leakage current since the leakage current was irregularly increased or decreased at a temperature of $22^{\circ}C$ to $32^{\circ}C$ and a humidity of 60.0% to 96.0%. The insulation resistance in the vicinity of $26^{\circ}C$ was $10.70M{\Omega}$ to $4,000.00M{\Omega}$ and was low from $9.10M{\Omega}$ to $1,000.00M{\Omega}$ before and after $26^{\circ}C$. As the humidity was increase in a range of 60%~96%, the insulation resistance was reduced from $4,000.00M{\Omega}$ to $4.80M{\Omega}$, which indicates that the temperature and humidity had an influence on the insulation resistance. The leakage current and the insulation resistance of the branch circuit to the cooking facilities were compliant with less than 1.00 mA and more than $0.20M{\Omega}$. Leakage current of 1.89 mA was non-compliant but the insulation resistance was compliant with the value of $65.00M{\Omega}$.

• Physical Therapy Korea
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• v.28 no.1
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• pp.1-12
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• 2021

While efforts have been made to address fall-related injuries in older adults, the problem is unsolved to date. The purpose of this review is to provide a guideline for fall and injury prevention programs in older adults, based on evidence generated over the past 30 years. Research articles published between 1990 and 2020 have been searched on PubMed, using keywords, including but not limited to, falls, hip fracture, injuries, intervention, older adults, prevention, hip protector, vitamin D, safe landing strategy, and exercise. Total of 98 articles have been found and categorized into five intervention areas: exercise program, hip protector, safe landing strategy, vitamin D intake, and compliant flooring. Furthermore, the articles have been rated based on their study design: class 1, randomized controlled trials; class 2, non-randomized controlled trials; class 3, experimental studies; class 4, all other studies. Exercise programs have shown to decrease the risk of fall, and associated injuries. Hip protectors, safe landing strategy, and vitamin D intake were effective in reducing a risk and incidence of hip fracture during a fall. Furthermore, compliant flooring has also decreased hip fracture risk without affecting balance. An integrated approach combining exercise program, wearing a hip protector, teaching safe landing strategies, scheduled vitamin D intake, and compliant flooring installation, is suggested to address fall-related injuries in older adults.

• Korean Journal of Schizophrenia Research
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• v.22 no.2
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• pp.42-50
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• 2019

Objectives: In this preliminary study, we investigated the clinical characteristics of patients who were first diagnosed with psychotic disorder and explored the impact of the adherence to antipsychotics on long-term medical use. Methods: All national health insurance claims related to psychotic disorders including gender, age, income, and drug compliance, from January 1, 2008 to December 31, 2015, were examined. With trend test using Medication Possession Ratio (MPR), we compared the medical use between the compliant group (MRP≥0.8) and the comparative non-compliant group (0.2≤MPR<0.8). Results: Among 28,095 participants in total, 16,239 patients (57.8%) were diagnosed as schizophrenia; the 30s were the most common (n=7,151, 25.5%). Drug compliance was generally low regardless of the diagnosis and was the lowest among 20s with the 40-60% range of income. The compliant group showed lower psychiatric and medical use than the comparative group in the following years (p<0.0001). Conclusion: These findings suggest that patients in the 20s and 30s with the 40-60% range of income, who are diagnosed with schizophrenia at the first psychiatric visit, may need more clinical and political attention. The results also emphasize the importance of initial drug adherence to antipsychotics in reducing long-term psychiatric costs.

• Journal of Ocean Engineering and Technology
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• v.1 no.2
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• pp.39-51
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• 1987

석유시추 보호관의 비선형 운동을 시뮬레이트하는 유효한 해법이 non-uniform grid 유한차분법과 implicit time 적분법에 근거하여 제시되었다. 극한 상태에 있는 지지 플랫폼의 상승 가속도에 의해 생기는 보호관의 동적 좌굴형 반응에 관하여 상세히 연구되었고, 이 반응에 미치는 중요 변수가 규명되었다. 운동의 현저한 감소와 이에 따른 응력들이 컴플라이언트 행오프(hang-off)를 적용시킴으로써 얻어졌다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.10B
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• pp.1675-1689
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• 2000

We present CReMeS a CORBA-compliant design and implementation of a new real-time communication service. It provides for efficient predictable and scalable communication between information producers and consumers. The CReMeS architecture is based on MidART's Real-Time Channel-based Reflective Memory (RT-CRM) abstraction. This architecture supports the separation of QoS specification between producer and consumer of data and employs a user-level scheduling scheme for communicating real-time tasks. These help us achieve end-to-end predictability and allows our service to scale. The CReMeS architecture provides a CORBA interface to applications and demands no changes to the ORB layer and the language mapping layer. Thus it can run on non real-time Off-The-Shelf ORBs enables applications on these ORBs to have scalable and end-to-end predictable asynchronous communication facility. In addition an application designer can select whether to use an out-of-band channel or the ORB GIOP/IIOP for data communication. This permits a trade-off between performance predictability and reliability. Experimental results demonstrate that our architecture can achieve better performance and predictability than a real-time implementation of the CORBA Even Service when the out-of-band channel is employed for data communication it delivers better predictability with comparable performance when the ORB GIOP/IIOP is used.

• Earthquakes and Structures
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• v.6 no.1
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• pp.71-87
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• 2014

Interaction between closely-spaced buildings subject to earthquake induced strong ground motions, termed in the literature as "seismic pounding", occurs commonly during major seismic events in contemporary congested urban environments. Seismic pounding is not taken into account by current codes of practice and is rarely considered in practice at the design stage of new buildings constructed "in contact" with existing ones. Thus far, limited research work has been devoted to quantify the influence of slab-to-slab pounding on the inelastic seismic demands at critical locations of structural members in adjacent structures that are not aligned in series. In this respect, this paper considers a typical case study of a "new" reinforced concrete (R/C) EC8-compliant, torsionally sensitive, 7-story corner building constructed within a block, in bi-lateral contact with two existing R/C 5-story structures with same height floors. A non-linear local plasticity numerical model is developed and a series of non-linear time-history analyses is undertaken considering the corner building "in isolation" from the existing ones (no-pounding case), and in combination with the existing ones (pounding case). Numerical results are reported in terms of averages of ratios of peak inelastic rotation demands at all structural elements (beams, columns, shear walls) at each storey. It is shown that seismic pounding reduces on average the inelastic demands of the structural members at the lower floors of the 7-story building. However, the discrepancy in structural response of the entire block due to torsion-induced, bi-directionally seismic pounding is substantial as a result of the complex nonlinear dynamics of the coupled building block system.

• Clinical and Experimental Reproductive Medicine
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• v.42 no.4
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• pp.169-174
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• 2015

Objective: To assess compliance with Korean guidelines for embryo transfer, the possible reasons for non-compliance, and multiple pregnancies according to each specific condition in compliant cycles. Methods: A single-institution, retrospective study was conducted of 256 fresh in vitro fertilization cycles during 2012-2014. To assess compliance with Korean guidelines, the maximum recommended number of embryos transferred (according to criteria of age, transfer day, and presence of favorable conditions) was compared with the actual number of embryos transferred. Clinical pregnancy rate (PR) was assessed as the percentage of pregnant women resulting from each set of transfer conditions, including the number of embryos transferred. The multiple pregnancy rate (MPR) was calculated as the percentage of pregnant women with a multifetal pregnancy. Results: The compliance rate with the Korean guidelines was 96.5% (247/256). Non-compliance occurred in nine cycles owing to poor embryo quality, repeated implantation failure, or hostile endometrium. In compliant cycles, the PR was 31.2% (77/247), and the MPR was 27.3% (21/77; 20 twins and one triplet). Higher MPR was noted in two types of transfer conditions: transfer of three cleavage embryos in women aged 35-39 years with favorable conditions (66.7%; primarily from those aged 35-37 years) and transfer of two blastocysts in women aged ${\geq}40$ years with favorable conditions (50%). Conclusion: Under the Korean guidelines, compliance rate was high in our center. Multiple pregnancies occurred primarily in group with favorable conditions. In high-risk groups for multiple pregnancies, reducing number of embryos transferred should be considered than suggested in the guideline.

• Journal of Korea Multimedia Society
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• v.19 no.3
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• pp.595-602
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• 2016

With the evolution and development of many kinds of healthcare devices and techniques, u-health standards have emerged as a major issue. Yet, most legacy medical devices and systems are still being used without deployment of the standards. Therefore, it is required to support backward compatibility for u-health standard-compliant systems to communicate with legacy non-standard medical and healthcare devices. This paper proposes a new scheme to support backward compatibility of IEEE 11073 system by adding a codec module to IEEE 11073 agent. The codec converts data sent by non-standard health devices to IEEE 11073 MDER data. Plus, we implemented the proposed IEEE 11073 agent with an Intel Edison board which is one of popular open source H/W platforms. The IEEE 11073 manager of the proposed system can monitor and control legacy non-standard devices through the proposed agent system. In our experimental results, we examined the proposed system can support interoperability between u-health standard and non-standard devices and contribute to the growth and expansion of u-health services.