• Korean Journal of Applied Biomechanics
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• v.19 no.1
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• pp.27-36
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• 2009

The purpose of this study was to identify effects of restricted trunk motion on the performances of the maximum vertical jump. Ten healthy males performed normal countermovement jump(NJ) and control type of countermovement jump(CJ), in which subjects were required to restrict trunk motion as much as possible. The results showed 10% decreases of jumping height in CJ compared with NJ, which is primarily due to vertical velocity at take off. NJ with trunk motion produced significantly higher GRF than RJ, especially at the early part of propulsive phase, which resulted from increased moments on hip joint. And these were considered the main factors of performance enhancement in NJ. There were no significant differences in the mechanical outputs on knee and ankle joint between NJ and RJ. With trunk motion restricted, knee joint alternatively played a main role for propulsion, which is contrary on the normal jump that hip joint was highest contributor. And restricted trunk motion resulted in the changes of coordination pattern, knee-hip extension timing compared with normal proximal-distal sequence. In conclusion these results suggest that trunk motion is effective strategy for increasing performance of vertical jumping.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.2
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• pp.209-215
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• 2020

In order to understand the characteristics of natural droughts, it is very important to interpret the spatio-temporal relationship between different types of droughts. In this study, meteorological and hydrological drought events were defined to account for the overlap between drought duration and spatial extent in three dimensions (i.e., latitude, longitude, and timing). In other words, the spatio-temporal drought propagation characteristics were analyzed based on the drought characteristic factors (duration, area, depth, center). The drought map considering the characteristics of spatio-temporal drought propagation can be used to find the fundamental cause of the hydrological drought which is expected to frequently occur in the future. In addition, the drought map is expected to be useful in preparing an effective drought response plan.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.5
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• pp.147-156
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• 2008

As the management of fuel efficiency becomes globally reinforced in attempts to find an environment-friendly vehicle that will operate against global warming, the interest in and the demand for the type of vehicle with a high-efficiency diesel engine using light oil. However, it also emits a greater amount of PM (particulate matter) and NOx than emissions from vehicles using other types of fuels. Therefore, the DME (Dimethyl Ether), an oxygen containing fuel draws attention as an alternative fuel for light oil that can be used for diesel engines since it generates very little smoke. But to develop and compare performance of an electric controlled common-rail DME engine, engine tests requires optimized injection conditions at required engine RPM and engine torque. These injection conditions cannot be set freely and the data configuration through the experimentally repeated application requires much time as well as a significant amount of errors and effort. The object of this study is to configure the basic injection map using the results of the DME engine experiments performed so far. For this, in this study, the functionalization of the required equations were performed along with the basic review of the factors that had influence on the data map. Through this, the information on the injection pressure, injection amount, injection duration, injection timing, etc. under certain operation condition could be obtained.

• The Journal of Korean Academic Society of Nursing Education
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• v.7 no.2
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• pp.245-253
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• 2001

The aim of this study is to describe degree of fatigue and factors related to fatigue in patients with rheumatoid arthritis. The subjects of the study consist of one hundred fifty-eight outpatients with rheumatoid arthritis at three university hospitals in Taegu between July 10 and August 30, 1999. The instrument used in this study was the Multidimensional Assessment of Fatigue developed by Belza et al.(1995) and revised by Jung, Bok Hee. Kim, Myung Ae(1998). Analysis of data was done by using the descriptive statistics, t-test, ANOVA and Duncan with SPSS program. The major findings can be summarized as follows: 1. Degree of fatigue in patient with Rheumatoid Arthritis was shown the average 22.91 out of the total scores 40. Four subscales of fatigue scores are common fatigue degree 6.37, fatigue timing at the last week 5.92, distress due to fatigue 5.40 and degree of daily activity fatigue 5.22. Among the realms of daily activity fatigue, outdoor activity(6.00), sexual life(5.84), doing the household(5.66), shopping(5.61), other exercise except stroll(5.54) were shown the high degree of fatigue and cooking(4.97), a stroll(4.48), recreation(4.35) showed the low degree of fatigue. 2. There were no significant differences on the total degree of fatigue according to demographic variables. But there were some significant differences on the subscale fatigue scores according to demographic variables. Degree of daily activity fatigue according to sex was shown significant difference (t=-2.358, p=.020), and according to education level was shown significant difference(F=3.938, p=.005) and common fatigue degree according to age was shown significant difference(F=2.853, p=.026). Conclusively fatigue is one of difficult problems for patients with rheumatoid arthritis. Therefore it is necessary to develop some nursing intervention for reducing fatigue of rheumatoid arthritis patients.

• Journal of Korean Academy of Nursing
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• v.49 no.6
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• pp.701-712
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• 2019

Purpose: Despite the high drinking rates and the complexity of drinking behaviors in adolescents, insufficient attention has been paid to their drinking patterns. Therefore, we aimed to identify patterns of adolescent drinking behaviors and factors predicting the distinct subgroups of adolescent drinking behaviors. Methods: We analyzed nationally representative secondary data obtained in 2017. Our final sample included 24,417 Korean adolescents who had consumed at least one glass of alcohol in their lifetime. To investigate patterns of drinking behaviors, we conducted a latent class analysis using nine alcohol-related characteristics, including alcohol consumption levels, solitary drinking, timing of drinking initiation, and negative consequences of drinking. Furthermore, we investigated differences in demographics, mental health status, and characteristics of substance use across the latent classes identified in our study. To do so, we used the PROC LCA with COVARIATES statement in the SAS software. Results: We identified three latent classes of drinking behaviors: current non-drinkers (CND), binge drinkers (BD), and problem drinkers (PD). Compared to the CND class, both BD and PD classes were strongly associated with higher academic year, lower academic performance, higher levels of stress, suicidal ideation, lifetime conventional or electronic cigarette use, and lifetime use of other drugs. Conclusion: Health professionals should develop and implement intervention strategies targeting individual subgroups of drinking behaviors to obtain better outcomes. In particular, health professionals should consider different characteristics across subgroups of adolescent drinking behaviors when developing the interventions, such as poor mental health status and other substance use among binge and problem drinkers.

• Clinical and Experimental Reproductive Medicine
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• v.43 no.4
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• pp.247-252
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• 2016

Objective: Heparin can modulate proteins, and influence processes involved in implantation and trophoblastic development. This study aimed to assess the improvement of clinical pregnancy and implantation rates after local intrauterine injection of low-molecular-weight heparin (LMWH) in patients undergoing intracytoplasmic sperm injection (ICSI). Methods: A randomised case/control design was followed in women scheduled for ICSI. The study arm was injected with intrauterine LMWH during mock embryo transfer immediately following the ovum pickup procedure, while the control arm was given an intrauterine injection with a similar volume of tissue culture media. Side effects, the clinical pregnancy rate, and the implantation rate were recorded. Results: The pregnancy rate was acceptable (33.9%) in the LMWH arm with no significant reported side effects, confirming the safety of the intervention. No statistically significant differences were found in the clinical pregnancy and implantation rates between both groups (p= 0.182 and p= 0.096, respectively). The odds ratio of being pregnant after intrauterine injection with LMWH compared to the control group was 0.572 (95% confidence interval [CI], 0.27-1.22), while the risk ratio was 0.717 (95% CI, 0.46-1.13; p= 0.146). No statistical significance was found between the two groups in other factors affecting implantation, such as day of transfer (p= 0.726), number of embryos transferred (p= 0.362), or embryo quality. Conclusion: Intrauterine injection of LMWH is a safe intervention, but the dose used in this study failed to improve the outcome of ICSI. Based on its safety, further research involving modification of the dosage and/or the timing of administration could result in improved ICSI success rates.

• Journal of Digital Convergence
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• v.15 no.9
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• pp.223-230
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• 2017

In the current wireless Internet environment, using a mobile device to quickly access a web site is closely related to measuring the performance of a website. When accessing a website, the user has a long time to access the website and has no access to the website.In this case, the performance of the web site should be improved by measuring and analyzing the performance of the connection delay due to a problem of the web site.Among the performance measurement factors of Web sites, Web page loading time is a very important factor for a successful service business in the situation where most of e-commerce business is being developed as a web-based service.An open source tool was analyzed to analyze the performance of the e-commerce web page to present problems, software optimization methods and hardware optimization methods. Applying two optimization methods to suit the environment will enable stable and e-commerce websites.

• Journal of Astronomy and Space Sciences
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• v.29 no.2
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• pp.181-189
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• 2012

To broaden the understanding of classical Cepheid structure, evolution and atmospheres, we have extended our continuing secret lives of Cepheids program by obtaining XMM/Chandra X-ray observations, and Hubble space telescope (HST) / cosmic origins spectrograph (COS) FUV-UV spectra of the bright, nearby Cepheids Polaris, ${\delta}$ Cep and ${\beta}$ Dor. Previous studies made with the international ultraviolet explorer (IUE) showed a limited number of UV emission lines in Cepheids. The well-known problem presented by scattered light contamination in IUE spectra for bright stars, along with the excellent sensitivity & resolution combination offered by HST/COS, motivated this study, and the spectra obtained were much more rich and complex than we had ever anticipated. Numerous emission lines, indicating $10^4$ K up to ${\sim}3{\times}10^5$ K plasmas, have been observed, showing Cepheids to have complex, dynamic outer atmospheres that also vary with the photospheric pulsation period. The FUV line emissions peak in the phase range ${\varphi}{\approx}0.8-1.0$ and vary by factors as large as $10{\times}$. A more complete picture of Cepheid outer atmospheres is accomplished when the HST/COS results are combined with X-ray observations that we have obtained of the same stars with XMM-Newton & Chandra. The Cepheids detected to date have X-ray luminosities of log $L_X{\approx}28.5-29.1$ ergs/sec, and plasma temperatures in the $2-8{\times}106$ K range. Given the phase-timing of the enhanced emissions, the most plausible explanation is the formation of a pulsation-induced shocks that excite (and heat) the atmospheric plasmas surrounding the photosphere. A pulsation-driven ${\alpha}^2$ equivalent dynamo mechanism is also a viable and interesting alternative. However, the tight phase-space of enhanced emission (peaking near 0.8-1.0 ${\varphi}$) favor the shock heating mechanism hypothesis.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.12
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• pp.1412-1422
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• 2010

A bistatic radar using the pulse chasing can detect a target to track successive transmitted pulses using a receive beam for effectively scanning the cosite search area. When tracking a transmitted pulse with the receive beam, some beam pointing errors within pulse-to-pulse can cause the timing error in received pulse and the variation of the signal strength. In this paper, we have proposed that some errors due to the receive beam pointing error could limit the MTI filter's performance and derived that the relationship between the MTI performance and the geometric factors which are the inherent properties in bistatic configuration. Through the simulation, we have considered the limitations of the improvement performance restricted by the receiving beam pointing error and confirmed the contribution to the performance improvement in maintaining the receiving beam pointing error of under 0.5 degrees.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.13 no.1
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• pp.104-109
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• 1991

Loss of mandibular continuity due to neoplasm, trauma, or infection results in major esthetic and biologic compromise. The use of costochondral grafts for reconstruction of temporomandibular joint, described first by Gillies in 1920, has been accepted as a suitable method for replacing the mandibular condyle, especially in growing children. Autogenous iliac bone graft has been a satisfactory source of mandibular reconstruction since Sykoffs report in 1900. Autogenous bone grafts from the posterior aspects of the ilium provide large amount of PMCB with acceptable donor site morbidity. In timing of reconstruction, initial disease, age, medical history, growth and development, esthetic and psychologic factors should be considered. We present a case of osteosarcoma in the mandible that was treated by a hemimandibulectomy and the defect was reconstructed 20 months later with composite method of costochondral and posterior iliac bone graft.