• International Journal of Highway Engineering
• /
• v.13 no.1
• /
• pp.1-11
• /
• 2011

This study is aimed at suggesting a plan for creating a landscape environment by grasping a landscape preference according to the change of middle span and sag ratio which is a consideration factor when designing the suspension bridge representing long-span bridges and image property of the bridge while applying SD method to a relation between landscape preference and image factor, and a connection of design element with image factor. An analysis on landscape preference about the bridge landscape showed from what the longer the length of middle span, the extent of sag ratio of preference decreased, the longer the middle span low sag ratio was preferred and the higher the landscape preference became. In landscape preference and image factor, the attribute of sag ratio with high landscape preference was all positively correlated with "stability", "plasticity", and "aesthetic" but an influence of "plasticity" was insignificant. In the relation between design element and image factor, the factor of middle span and sag ratio was more related to the factor of "stability" and the lower the sag ratio and the longer the middle span, the higher the "stability" was rated. This result showed the image property of "plasticity" was insignificant among the one of preference in landscape and to highlight the one of "plasticity" a complementary experiment was done with a change in balance and symmetry elements not in proportional element of middle span and sag ratio. The result showed the image property of "plasticity" was more highlighted in the suspension bridge of 3-tower and different bilateral symmetry at sag, and when designing the landscape of suspension bridge later on, the elements of balance and symmetry as well as the proportional element should be considered and reflected in the design.

• Journal of Sericultural and Entomological Science
• /
• v.41 no.3
• /
• pp.154-166
• /
• 1999

General characteristics and life span of silkworm moth were investigated amongst 277 gene resources preserved and maintained in Korea. Silkworm varieties were classified according to the commercial characteristics and the viability of tested varieties. There were significant differences among the eight different commercial characteristics of silkworm such as whole larval period, duration of 5th instar, pupal body weight, single cocoon weight, cocoon shell weight, cocoon shell ratio, cocoon yield and longevity, Tropical race showed the longest life span among the other five geographical races, and followed by Japanese, European, Chinese and Korean race in order. In the longevity of each variety, Daizo(sdi) showed the shortest life span with 4.3days, and J037 was the longest as 16.0 days. Average longevity of female was 11.1 days as showed 3.0 days longer than that of male which was 8.2 days. Total average longevity of the whole varieties was 9.7days. In the correlation between the longevity and commercial characteristics, there was a tendency that the commercial characteristics became better when the life span was longer. According to the result of Complete Linkage Cluster Analysis, the genetic resources of 277 silkworm varieties classified into 5 groups such as “Group I”for short life span with low cocoon yielding “Group II”for middle life span with middle cocoon yielding,“Group III”for the shortest life span with low cocoon yielding, “Group IV”for high pupation rate and the highest cocoon yielding with comparatively long life span, and “Group V”for the longest life span with comparatively high cocoon yielding.

• Structural Engineering and Mechanics
• /
• v.34 no.5
• /
• pp.635-662
• /
• 2010

In this study, the effect of superstructure-abutment continuity on the distribution of live load effects among the girders of integral abutment bridges (IABs) is investigated. For this purpose, two and three dimensional finite element models of several single-span, symmetrical integral abutment and simply supported (jointed) bridges (SSBs) are built and analyzed. In the analyses, the effect of various superstructure properties such as span length, number of design lanes, girder size and spacing as well as slab thickness are considered. The results from the analyses of two and three dimensional finite element models are then used to calculate the live load distribution factors (LLDFs) for the girders of IABs and SSBs as a function of the above mentioned parameters. LLDFs for the girders are also calculated using the AASHTO formulae developed for SSBs. Comparison of the analyses results revealed that the superstructure-abutment continuity in IABs produces a better distribution of live load effects among the girders compared to SSBs. The continuity effects become more predominant for short span IABs. Furthermore, AASHTO live load distribution formulae developed for SSBs lead to conservative estimates of live load girder moments and shears for short-span IABs.

• Journal of the Korean Home Economics Association
• /
• v.30 no.4
• /
• pp.153-165
• /
• 1992

The objectives of this study were to develop a probabilistic model for both hypotheses testing and mobility prediction. Methodologies being used for the analysis include multivariated analysis for descriptive statistics and logit model for hypotheses testing and prediction. The study used questionaire survey data conducted by Korean Research Institute for Human Settlements (KRIHS) in 1988. There were a total of 1,620 Samples, and both SPSS and Limdep software packages were used for statistical analysis and model testing. The major findings were highlighted as follows; The residential mobility over family life span by the social class were developed with the use of the probability model. Most of households in low class moved downwardly. They had lived the small-owned single detached house in first family life span and moved into the small-rented single detached house in next family life span. Most of households in middle class moved upwardly. They had lived the small-owned apartment in first family life span and moved into the large-owned single detached house in last family life span. Most of households in high class horizontally. They had lived the large-owned single detached house in first family life span and moved into the same one except in last family life span.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2012.05a
• /
• pp.594-597
• /
• 2012

Optimal link configuration in optical link with concentrated residual dispersion per span (RDPS) in only one fiber span and 0 ps/nm of RDPS in other fiber spans of each half transmission section with respect to optical phase conjugator (OPC) placed at middle of total transmission length is induced in this paper.

• Journal of the Ergonomics Society of Korea
• /
• v.26 no.3
• /
• pp.59-65
• /
• 2007

In this study, six grip spans (45mm-65mm) were tested to evaluate the effects of handle grip span and user's hand size on maximum grip strength, individual finger force, and subjective ratings of comfort using a digital dynamometer with individual force sensors. Forty-six males were assigned into three hand size groups according to their hand lengths. Results showed that overall 55mm and 50mm grip spans were the most comfortable sizes and associated with the highest grip strength in the maximum grip force exertions, whereas 65mm grip span was rated as the least comfortable size as well as the lowest grip strength. In the interaction effect of grip span and hand size, small and middle hand sized participants rated the best preference and the least preference grip spans differently with large hand sized participants. With respect to the analysis of individual finger force, the middle finger force was the strongest and the highest contribution to the total finger force, followed by ring, index and little fingers. In addition, it was noted that each finger had a different optimal grip span for exerting maximum force resulting in a bowed contoured shaped handle for two-handle hand tools. Thus, the grip spans for two-handle hand tools might be designed according to the users' hand and finger anthropometrics to maximize performance and subjective perception of comfort.

• Earthquakes and Structures
• /
• v.8 no.4
• /
• pp.859-887
• /
• 2015

Structural health monitoring (SHM) has gained in popularity in recent years since it can assess the performance and condition of instrumented structures in real time and provide valuable information to the asset's manager and owner. Operational modal analysis plays an important role in SHM and it involves the determination of natural frequencies, damping ratios and mode shapes of a constructed structure based on measured dynamic data. This paper presents the operational modal analysis and seismic response characterization of the Tsing Ma Suspension Bridge of 2,160 m long subjected to different earthquake events. Three kinds of events, i.e., short-distance, middle-distance and long-distance earthquakes are taken into account. A fast Bayesian modal identification method is used to carry out the operational modal analysis. The modal properties of the bridge are identified and compared by use of the field monitoring data acquired before and after the earthquake for each type of the events. Research emphasis is given on identifying the predominant modes of the seismic responses in the deck during short-distance, middle-distance and long-distance earthquakes, respectively, and characterizing the response pattern of various structural portions (deck, towers, main cables, etc.) under different types of earthquakes. Since the bridge is over 2,000 m long, the seismic wave would arrive at the tower/anchorage basements of the two side spans at different time instants. The behaviors of structural dynamic responses on the Tsing Yi side span and on the Ma Wan side span under each type of the earthquake events are compared. The results obtained from this study would be beneficial to the seismic design of future long-span bridges to be built around Hong Kong (e.g., the Hong Kong-Zhuhai-Macau Bridge).

• Proceedings of the Korea Concrete Institute Conference
• /
• 2000.10a
• /
• pp.629-634
• /
• 2000

In this study, 9 reinforced concrete(RC) continuous beams were tested to investigate the arch action. By measuring longitudinal steel strains during the whole loading stages up to failure, the development of arch action is evaluated. Variables included are span length, longitudinal steel ratio and the presence of stirrups. As a result, it was known that measured steel tension in the span is substantially higher than the conventionally calculated values, and it was appeared that near the middle of the shear span the measured values exceeded the calculated values by factors of up to 1.4 or more.

• Proceedings of the KSR Conference
• /
• 2006.11b
• /
• pp.530-537
• /
• 2006

Recently, the railroad route plan is trying to minimize the damage of the local resident which is caused by railroad construction. For this reason, reducing the banking height of soil roadbed, lowering the bridge girder height of a solid intersection and a part of cross river, the through bridge type which can achieve a required span length must apply. The representative through bridges of railroad are arch bridges, truss bridges and plate girder bridges, the through plate girder bridge of variable section can apply that the span length of these bridges is about $30{\sim}50m$, namely, middle span length bridge types, and that can satisfy structural capacity and beauty of railroad at the same time. This paper introduces plan and design process of the Su-eo cheon bridge applied by a through plate girder bridge type of the Jinju-Gwangyang double track 6th construction ordered at Korea Rail network Authority in 2005.

• Journal of information and communication convergence engineering
• /
• v.20 no.4
• /
• pp.235-241
• /
• 2022

A dispersion map was proposed to improve the compensation effect of a distorted WDM (wavelength division multiplexed) channel in a dispersion-managed link coupled with optical phase conjugation. The dispersion map is an origin-symmetric structure around the optical phase conjugator in the middle of the transmission path. In addition, the dispersion map has a form in which a constant dispersion accumulation pattern is repeated regularly. Through simulation, we confirmed that the application of the origin-symmetric dispersion map with a repetitively shaped configuration was more effective in compensating for the distorted WDM channel than in the dispersion-managed link with a conventional dispersion map. In addition, we confirmed that the compensation effect could be increased when the cumulative dispersion distribution of the origin-symmetric distribution map had a positive value in the first half section and a negative value in the second half section. Further, we observed that as the number of repeated dispersion accumulation patterns increased, the residual dispersion per span should also be increased.