• 한국도로학회논문집
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• 제19권5호
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• pp.59-68
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• 2017

PURPOSES : The objective of this study is to evaluate the potential risk level of road cave-ins due to subsurface cavities based on the deflection basin measured with falling weight deflectometer (FWD) tests. METHODS: Ground penetrating radar (GPR) tests were conducted to detect road cavities. Then FWD tests were conducted on 13 pavement test sections with and without a cavity. FWD deflections and a deflection ratio was used to evaluate the effect of geometry of the cavity and pavement for road cave-in potentials. RESULTS : FWD deflection of cavity sections measured at 60 cm or a closer offset distance to a loading center were 50% greater than more robust sections. The average deflection ratio of the cavity sections to robust sections were 1.78 for high risk level cavities, 1.51 for medium risk level cavities, and 1.16 for low risk level cavities. The relative remaining service life of pavement with a cavity evaluated with an surface curvature index (SCI) was 8.1% for the high level, 21.8% for the medium level, and 89.8% compared to pavement without a cavity. CONCLUSIONS : FWD tests can be applied to detect a subsurface cavity by comparing FWD deflections with and without a cavity measured at 60 cm or a closer offset distance to loading center. In addition, the relative remaining service life of cavity sections based on the SCI can used to evaluate road cave-in potentials.

• Journal of Ecology and Environment
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• 제31권4호
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• pp.291-295
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• 2008

Weight loss and nutrient dynamics of oak and pine leaf litter during decomposition were investigated from December 2005 through June 2008 at Mt. Worak National Park as a part of National Long-Term Ecological Research Program in Korea. The decay constant (k) of oak and pine leaf litter were 0.314 and 0.217, respectively. After 30 months decomposition, remaining weight of oak and pine leaf litter was 45.5% and 58.1%, respectively. Initial C/N ratio of oak and pine leaf litter was 53.4 and 153.0, respectively. Carbon % of initial oak and pine leaf litter was similar with each other; however, nitrogen content of initial oak leaf litter (0.85%) was greater than that of initial pine leaf litter (0.33%). N and P concentration in both decomposing leaf litter increased significantly during decomposition. There was no net N and P mineralization period in decomposing pine leaf litter. K, Ca and Mg concentration in both decomposing leaf litter showed different pattern with those of N and P. After 30 months decomposition, remaining nutrients in oak and pine leaf litter were 97.7 and 216.2% for N, 123.2 and 216.5% for P, 39.3 and 44.8% for K, 47.9 and 40.6% for Ca, 30.7 and 51.2% for Mg, respectively.

• 한국치위생학회지
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• 제20권3호
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• pp.281-290
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• 2020

Objectives: Stress is the cause of several illnesses, in older people, stress may also cause various social problems. The oral health of older adults is closely related to the quality of life, and chewing ability is particularly important for their general health. The purpose of this study was to investigate the relationship between stress, the number of teeth remaining, and the chewing ability, which reflects the oral health status among older adults. Methods: This study evaluated the stress level and chewing ability of adults older than 65 years using the 6th (2014-2015) Korea National Health and Nutrition Examination data. The total number of remaining teeth was determined based on the data of the teeth conditions. Results: There was an association between stress and chewing ability among older adults. The odds ratio of chewing function increased by 2.67 times (crude OR=2.67; 95% CI=1.88-3.79) with increased stress. After adjusting, the odds ratio increased to 2.74 times (adjusted OR=2.74; 95% CI=1.88-3.98). Conclusions: Reducing stress may facilitate effective oral health management and improve the overall quality of life in older adults. The findings of this study may help in the discovery of various approaches s to reducing stress in older adults and provide relevant information for oral health education.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제14권4호
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• pp.295-304
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• 2014

Communication infrastructure supports wide variety of mobile services such as photo and file sharing, location tracking, social network services and instant messaging. However, instances like power-loss and natural disasters disrupt these communication infrastructures unable to render support to these mobile services. Delay-tolerant networks (DTNs) offer a solution to these problems at hand. By utilizing mobility and opportunistic contacts among mobile devices, a plausible communication network can be establish and enable support to mobile applications. This paper presents an energy-efficient, reliable message delivery routing scheme with message prioritization rules for DTN. It uses the context information of nodes (mobile devices) such as the contact history (location and time of contact), speed/velocity, moving direction to determine the best forwarders among nodes in the network. The remaining energy of the nodes is also used to determine the message types a node can deliver successfully. The simulation results show that proposed approach outperforms Epidemic and Prophet routing schemes in terms of delivery ratio, overhead ratio, delivered messages per types and remaining energy.

• 정보처리학회논문지C
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• 제15C권4호
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• pp.303-310
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• 2008

ad-hoc네트워크에서 네트워크의 생존시간을 연장하기 위해서는 네트워크 트래픽 부하를 전체 네트워크에 골고루 분산시켜 노드당 평균 에너지 소모율을 균일하게 유지할 수 있어야만 한다. 본 논문에서는 노드의 에너지 잔량 및 사용 빈도 등을 고려해 경로를 설정하는 수정 AODV 프로토콜을 제안하였다. 또한 경로 재설정 과정에서 생성되는 엄청난 양의 AODV 제어 메시지 발생으로 인한 에너지 소모를 줄이기 위해 출발지 노드의 버퍼에 다중 경로 정보를 저장하도록 하였다. 링크 단절 시 경로 재설정 과정 전에 경로 테이블에 저장된 경로 정보를 활용할 수 있도록 하였다. 본 논문에서 제안한 알고리즘의 성능 평가를 위해 기존 AODV 및 에너지 기반 라우팅 프로토콜인 MMBCR방식과 전체 노드의 에너지 잔량, 네트워크 생존시간 및 데이터 패킷 수신율 등 3가지 평가 항목을 사용해 비교하였다.

• 말소리와 음성과학
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• 제5권4호
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• pp.211-216
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• 2013

The IVA(Independent Vector Analysis) is a well-known FD-ICA method used to solve the frequency permutation problem. It generally works quite well for blind source separation problems, but still needs some improvements in the frequency bin permutation problem. This paper proposes a post-processing method which can improve the source separation performance with the IVA by fixing the remaining frequency permutation problem. The proposed method makes use of the correlation coefficient of power ratio between frequency bins for separated signals with the IVA-based 2-channel source separation. Experimental results verified that the proposed method could fix the remaining frequency permutation problem in the IVA and improve the speech quality of the separated signals.

• 한방안이비인후피부과학회지
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• 제16권1호
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• pp.141-153
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• 2003

Introduction : The causes of sudden sensorineural hearing loss have not been detemined with precision until recently, but viral infections and vascular insufficiencies, such as vascular spasm, occlusion of sludging of erythrocytes were considered as major factors. The treatment has not been determined with precision until recently. It is similar to dizziness(眩暈). sudden dcafncss(暴聾) and congestion-fire deafness(痰火聾) in Oriental Medicine. It is very rare that someone has sudden hearing loss and visit Oriental Medicine Clinic right that time. But we expect if they take a Oriental treatment on thc right time. more effective for their symptom. Subjects : Following conclusions were reached by measuring results of oricntal medical treatments for 40 patients who visited the clinic between January of 2000 and December of 2002, and received treatments continuously for more than 1 months of time. Methods : Among the selected 40 patients. 30 patients belong to Group Ⅰ, which consisted of patients who had already visited a general hospital prior to visiting this clinic, achieved no recovery at all from sudden deafness despite going through more than 5 days of hospitalized treatments of steroidal medications. Group Ⅱ was consisted of 10 patients of sudden deafness who did not experience any steroidal treatments from other hospital prior to the oriental medical treatment. Results and conclusion : According to differentiation of syndrome. among 30 patients of the Group Ⅰ. 21 were categorized as excess syndrome patients and remaining 9 as deficiency syndrome paticnts. Among 10 patients of For Group Ⅱ, 5 were excess syndrome patients and remaining 5 were deficiency syndrome patients. Among Group Ⅰ, recovery ratio of excess syndrome patients was 47.7$\%$ and deficiency syndrome patients was 44.4$\%$ adding up recovery ratio of the group to be 46.1$\%$. Among Group Ⅱ, recovery ratio of excess syndrome patients was 80$\%$ and deficiency syndrome patients was 100$\%$ adding up recovery ratio of the group to be 90$\%$. Oriental medical treatments are generally more effective(90$\%$ recovery ratio) for Sudden Deafness than steroidal treatments. Oriental medical treatments are almost equally effective for both excess syndrome patients and deficiency syndrome patients. However, steroidal treatments for excess syndrom patients(45$\%$ recovery ratio) is much less effective than deficiency syndrome patients(73$\%$ recovery ratio). This indicates that steroidal treatments should be applied selectively to deficiency syndrome patients if applied at all. Even for patients with sudden deafness which hospitalized steroidal treatments did not result in any recovery at all, oriental medical treatments were able to achieve 46.1$\%$ recovery ratio.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표회 논문집(I)
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• pp.223-228
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• 1998

This study is to investigate on the remaining life of reinforced concrete apartment by using the probability of a reinforcing-steel corrosion and the carbonation tendency of domestic reinforced concrete apartments by using the statistic method. The results are as follow. ·To compare with the carbonation velocity of Kishitani's formula (x=3.727{{{{ SQRT { t} }}) when water-cement ratio is w=0.6, R=1, it is founded out that the carbonation velocity is slow a little in all area investigated and inland area, and fast a bit in coastal area. ·In the influencing factors in regard to the probability of reinforcing-steel corrosion, It seems that the influence of elapsed time is more effective than that of region. Therefore, it is necessary that it makes sure of the cover depth under apartment construction in recent so far as the durability is considered.

• 콘크리트학회논문집
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• 제12권5호
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• pp.69-80
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• 2000

This paper presents the prediction of remaining service life of the concrete due to steel corrosion caused by the following three cases; carbonation, using sea sand and using deicing salts. The assessment of initiation period was generalized considering the existing perdiction models in the literature, corrosion experiment and field assessment. To evaluate the prediction equation of rust growth, the corrosion accelerating experiments was performed. The polarization resistance was measured by potentiostat and the conversion coefficient of polarzation resistance to corrosion rate was determined by the measurement of real mass loss. Chloride content, carbonation, cover depth, relative humidity, water-cement ratio(W/C), and the use of deicing salts were taken into account and the resulting prediction equation of rust growth was proposed on the basis of these properties. The proposed equation is to predict the rust growth during any specified period of time and be effective in particular for predicting service life of concrete in the case of using sea sand.

• 대한정형도수물리치료학회지
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• 제20권2호
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• pp.21-26
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• 2014

Background: In the present study, we examined gender roles, job satisfaction, and the relationship between the two among orthopedic manual physical therapists (OMT). Methods: The subject of this study was 208 physical therapists working in the general hospital and rehabilitation in Daejeon. In order to examine the nature of the subject, we calculated the ratio of second finger length for fourth finger of predominant hand and completed the questionnaire to determine the general characteristics and job satisfaction. Results: The OMT and NOMT (non OMT) digit ratio results were not significantly different (p>.05). Digit ratio based on gender was also not significantly different between groups (p>.05). Among the job satisfaction survey items, OMT was significantly higher than NOMT in terms of Pride, Reflection of opinions, aptitude match, and field satisfaction (p<.05); however, there were no significant differences between groups for the remaining items. Digit ratio was not significantly related to any of the job satisfaction items (p>.05). Conclusions: We determined that gender roles had a limited influence on selecting and continuing with orthopedic physical therapy.