• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.10a
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• pp.159-166
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• 2000

Structures with a long span have a higher possibility of experiencing excessive vibration induced by human activities such as walking, running, jumping and dancing. These excessive vibration give occupants annoyance. The general method for the vibration analysis of structures subjected to walking loads is to apply a series of nodal loads with assigned time delays at the nodes. But this method has a limit in representing the walking loads. In this study, the equivalent nodal loads are introduced for an effective analysis of floor vibration induced by walking loads. And, walking loads with difference walking rate are measured and applied to the analytical model for numerical analysis.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.11
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• pp.1794-1803
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• 1989

This paper presents and evaluates a distributed routing algorithm for effective routing control in circuit-switched multistage interconnection networks. The proposed method uses the distributed control based on the incividual-switching element control and it is very effective for allowing any broadcast connection from a source to arbitrary number of destinadtions. The performnace of the proposed method is analyzed and evaluated by computer simulation in terms of the normalized average time delays.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1984.10a
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• pp.7-10
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• 1984

In this paper, the advantages of buffer insertion access method in comparison with other access methods to local area networks are analyzed. Sending and Receiving protocols in a data link layer are designed by a software method, We have derived both qeueing delays and the response time for the performance model that is proposed in this paper, and using the computer simulation, analyzed the performance for the proposed model in terms of the throughput rate- response time characteristrics. Based on the proposed model, the hardware design is implemented.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.2 s.95
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• pp.116-122
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• 1999

저차 동적계(특히 카오스계)에서 측정한 시계열의 잡음을 제거하기 위해서 SVD(Singular Value Decomposotion)을 이용한 새로운 간편하고 매우 효과적인 새로운 잡음 제거법이 소개되었다. 이 방법은 위상궤적(phase portraint)을 재구성하는데 중점을 두었으며, 궤적행렬(trajectory matrix)을 구성하는데 그 기본을 두었다. 이 궤적행렬에 SVD를 반복적으로 사용하여 신호와 잡음을 분리하였다. 이 방법은 Duffing계에서 측정한 잡음이 섞인 카오스 신호에 적용되었으며, 또한 실험에 의한 진폭변조된 신호에도 적용되었다.

• Korean Journal of Optics and Photonics
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• v.12 no.4
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• pp.339-344
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• 2001

We propose a method to represent binary data by modulating both the intensity and the phase of uniform plane waves with a twisted-nematic liquid crystal display for holographic digital data storage especially in a disk-shaped recording medium. As far as intensity modulation is concerned, our method is not different from the conventional method, because binary bit values 0 and 1 are represented by the dark (off) and lit (on) states of the liquid crystal display pixels, respectively (or vice versa). With our method, however, the on pixels are also controlled so that the beams passing through them can have one of two different phase delays. If the difference of the two phase delays is close to 180 degrees, we can reduce the dc component of the data image and thus improve the beam intensity uniformity at the holographic recording plane when Fourier plane holograms are recorded. The feasibility of our method is experimentally demonstrated. rated.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.05a
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• pp.497-502
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• 2001

We propose a method to represent binary data by modulating both the intensity and the phase of uniform plane waves with a twisted-nematic liquid crystal display for holographic digital data storage especially in a disk-shaped recording medium. As far as intensity modulation is concerned, our method is not different from the conventional method, because binary bit values 0 and 1 are represented by the dark (off) and lit (on) states of the liquid crystal display pixels, respectively (or vice versa). With our method, however, the on pixels are also controlled so that the beams passing through them can have one of two different phase delays. If the difference of the two phase delays is close to 180 degrees, we can reduce the dc component of the data image and thus improve the beam intensity uniformity at the holographic recording plane when Fourier plane holograms are recorded. The feasibility of our method is experimentally demonstrated.

• Korean Journal of Construction Engineering and Management
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• v.9 no.5
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• pp.214-226
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• 2008

Construction delay caused considerable losses to project parties. Avoiding construction delays is important to save costs for project stakeholders. The main objective of this paper is to identify major causes of construction delays of apartment construction projects in Vietnam. Sixteen causes of delay were identified through a questionnaire survey of 166 professionals. Factor analysis was employed to categorize these causes. The results of the survey revealed the main causes of delay of apartment projects in Vietnam are: (1) owner's and contractor'S financial difficulties; (2) lack of experienced contractors; (3) late delivery of materials; (4) late construction site handover; (5) owner's late payments for completed works; (6) low bid prices; (7) inappropriate construction method; and (8) defective works and unnecessary reworks. Factor analysis uncovered that causes of delay can be grouped under five categories labeled the five INs: incompetence, ineffectiveness, inadequateness, inapplicableness and inconceivableness. Comparative analysis between the Vietnam construction industry (VCI) and the Korea construction industry (KCI) has been performed to infer valuable lessons for researchers and practitioners in the VCI and the KCI. Comparative analysis indicated that main causes of delay in the VCI somewhat differ from main causes of delay in the KCI. However, "contractor'S financial difficulties", "late construction site handover", "unnecessary rework", "incapable designers", "site clearance difficulties" are common causes of delay in the VCI as well as the KCI. The findings of this research can be used as a guideline to overcome problems in the VCI as well as in other construction industries. Since Korea has emerged as the first largest foreign investor in Vietnam, the results of this study may be useful not only to practitioners and researchers in Vietnam but also to participants in Korea.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.10
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• pp.4723-4727
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• 2016

Background: There are substantial differences in the mortality rates of stomach cancer among the 47 prefectures in Japan, and Aomori prefecture is one of the most severely impacted. The aims of this study were to determine the incidence and mortality rates of stomach cancer in Aomori prefecture in comparison with Japan as a whole and cast light on reasons underlying variation. Methods: Data on stomach cancer cases were extracted from the Aomori Cancer Registry Database. Incidence rates for specific stages at the time of diagnosis were cited from Monitoring of Cancer Incidence in Japan, and mortality rates for stomach cancer in Aomori prefecture and the whole of Japan were obtained from Vital Statistics. Age-standardised incidence and mortality rates were calculated using the direct method. Results: The age-standardised incidence rate of stomach cancer in Aomori prefecture was higher than in the whole of Japan for males but lower for females. However, the age-standardised mortality rates were higher in Aomori prefecture in both sexes. The proportion of localised cancers was lower in Aomori prefecture than in the whole of Japan for most age groups. Conclusions: The lower rate for localised cancer suggests that higher age-standardised mortality rates are due to delays in diagnosis, despite an attendance rate for stomach cancer screening was higher in Aomori prefecture than in the whole of Japan. One plausible explanation for the failure of successful early detection might be poor quality control during screening implementation that impedes early detection.

• Child Health Nursing Research
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• v.15 no.1
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• pp.34-41
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• 2009

Purpose: In this study, a Checklist for Infant and Child Developmental Screening (CICDS) was designed for use by primary pediatric health care providers to identify infants and children with developmental delays. Method: Each Item of the CICDS was constructed referring to existing tools. In 5 public health centers of B city, 500 infants and children were selected at the age of 2, 4, 6, 12, & 18 months and assessed between October and December 2006, CICDS and the Korea Denver II were compared to assesses the validity of the CICDS. Results: The CICDS consisted of 30 items in 4 areas; Personal-social, Fine motor-adaptive, Language, Gross motor. The results of the CICDS correlated significantly with the result of Korea Denver II at each month of age. (r=0.19; p<.01). Of the 500 infants and children, 148 were "suspect" for development delays (sensitivity of 96%, specificity 73%). On the CICDS, 74.6% of children received same result as Denver II. In discriminant analysis, 89.9% of children were identified correctly by CICDS (p<.01). Conclusion: CICDS could be a screening procedures to quickly and reliably identify infants with developmental delays. It also provides a mean of recording measurements of development characteristics.

• Journal of Korean Society of Transportation
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• v.31 no.4
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• pp.3-17
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• 2013

The purpose of this study is to develop a traffic assignment model where the variable of signal intersection delay is taken into account in assigning traffic in large-scale network settings. Indeed, despite the fact that the majority of the increase in travel time or cost involving congested urban network or interrupted flow are accounted for by stop delays or congested delays at signal intersections, the existing traffic assignment models did not reflect this. The traffic assignment model considering intersection delays presented in this study was built based on the existing traffic assignment models, which were added to by the analysis technique for the computation of intersection delay provided in Korea Highway Capacity Manual. We can conclude that a multiple variety of simulation tests prove that this model can be applied to real network settings. Accordingly, this model shows the possibility of utilizing a model considering intersection delay for traffic policy decisions through analysis of effects of changes in traffic facilities on large urban areas.