• 항공우주정책ㆍ법학회지
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• 제5권
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• pp.321-384
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• 1993

The paper is to study and analyze the civil aviation industry of China and to present some cooperative and developing models between Korea and China in the fields of civil aviation on the basis of mutul benefit. In this study, civil aviation includes both the air transport industry and aircraft manufacturing industry. As it is not easy and realistic for us to conduct field survey on the civil aviation of China so far, this study has havily depended upon the literature data gathered from the ICAO and other published materials. This study includes the following major contents. 1. The historical development of China civil aviation 2. The present status and future prospect of Civil Aviation Adminstration of China(CAAC) 3. The present status of Chinese aircraft industry 4. Administration of airport and airspace of China 5. Air transport industry of China 6. The design of Korea-China civil aviation cooperation

• Earthquakes and Structures
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• 제9권2호
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• pp.431-453
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• 2015

A destructive earthquake, the magnitude of this earthquake was 7.2, hit Van, Turkey on October 23, 2011. After this devastating earthquake, a moderate earthquake which had 5.7 magnitude on November 9, 2011 occurred in Edremit, Van. These earthquakes caused heavy damages and collapses in many reinforced concrete buildings with loss of lives. In this paper, characteristics of ground motions of these earthquakes were studied and, deficiencies in structural elements and engineering faults such as poor workmanship and quality of construction, soft and weak stories, strong beam-weak column, short column, large overhang, hammering and unconfined gable wall were investigated. According to the observations, it was seen that, low quality of structural materials, lack of engineering services, inappropriate design and construction with insufficient detailing of the structural elements were the main reasons of heavy damages.

• Structural Engineering and Mechanics
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• 제69권2호
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• pp.177-191
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• 2019

The local topography has a significant effect on the characteristics of seismic ground motion. This paper investigates the influence of topographic effects on the seismic response of a train-bridge system. A 3-D finite element model with local absorbing boundary conditions is established for the local site. The time histories of seismic ground motion are converted into equivalent loads on the artificial boundary, to obtain the seismic input at the bridge supports. The analysis of the train-bridge system subjected to multi-support seismic excitations is performed, by applying the displacement time histories of the seismic ground motion to the bridge supports. In a case study considering a bridge with a span of 466 m crossing a valley, the seismic response of the train-bridge system is analyzed. The results show that the local topography and the incident angle of seismic waves have a significant effect on the seismic response of the train-bridge system. Leaving these effects out of consideration may lead to unsafe analysis results.

• Steel and Composite Structures
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• 제42권1호
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• pp.49-57
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• 2022

This paper presents a study on the behavior of a bolted T-stub to square tube connection using Thread-fixed One-side Bolts (TOBs) through tests and numerical simulations. It outlines a research work of four connections with focus on the failure modes and strengths of the connection under tensile load. It was observed that the thread anchor failure caused by shear failure of hole threads controlled the final failure of the connection in the tests. Meanwhile, the out-of-plane deformation of tube wall resulted in the contact separation between hole threads and bolt threads, which in turn reduced the shear strength of hole threads. Finite element models (FEMs) allowing for the configuration details of the TOBs fixed connection are then developed and compared with the test results. Subsequently, the failure mechanism of hole threads and stress distribution of each component are analyzed based on FEM results. It was concluded that the ultimate strength of connection was not only concerned with the shear strength of hole threads, but also was influenced by the plastic out-of-plane deformation of tube wall. These studies lay a foundation for the establishment of suitable design methods of this type of connection.

• Structural Engineering and Mechanics
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• 제87권1호
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• pp.19-28
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• 2023

This paper describes the experimental investigation of steel pallet rack beam-to-column connec-tions. Total behavior of moment-rotation (M-φ) curve and the effect of particular characteristics on the behavior of connection were studied and the associated load strain relationship and corre-sponding failure modes are presented. In this respect, an estimation of SPRBCCs moment and rotation are highly recommended in early stages of design and construction. In this study, a new approach based on Support Vector Machines (SVMs) coupled with discrete wavelet transform (DWT) is designed and adapted to estimate SPRBCCs moment and rotation according to four input parameters (column thickness, depth of connector and load, beam depth,). Results of SVM-WAVELET model was compared with genetic programming (GP) and artificial neural networks (ANNs) models. Following the results, SVM-WAVELET algorithm is helpful in order to enhance the accuracy compared to GP and ANN. It was conclusively observed that application of SVM-WAVELET is especially promising as an alternative approach to estimate the SPRBCCs moment and rotation.

• 수완나부미
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• 제5권2호
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• pp.67-80
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• 2013

A widely shared view identifies civil society with the set of nonprofit or nongovernmental organizations. This tradition reflects a long history of social theory viewed in institutional terms. Myanmar society has developed, mainly based on Buddhist culture and tradition. Buddhist practice necessitates public validation within an economy of merit in which moral action earns future rewards. Myanmar private voluntary associations have, since ancient times, played a vital role in achieving social purposes. Buddhist monasteries were the main education institutions in Myanmar. Until today, monastic schools, or monastic education centers as they are often called, have been the most important civil-society institutions bridging the accessibility gap in the state-run education system in government-controlled areas. Apart from social or community based that serve for public health in Myanmar there has been a number of religious organizations serving for the same. Moreover there appeared an association to very differently help those who need much urgent help. Since military coup in 1962, however, successive regimes have sought to stamp out civil society and permit only state-controlled organizations. Civil society re-emerged during the nation-wide pro-democracy demonstrations in 1988. After 1988 civil societies are allowed as like a political party to form. Now a day some civil societies have worked to start small-scale projects addressing local problems, but they must stay clear of politics.

• Structural Engineering and Mechanics
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• 제90권5호
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• pp.447-458
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• 2024

This study investigated the influence of scale ratio and vertical load on the seismic performance of Puzuo joints in traditional Chinese timber structures. Three low-cyclic reversed loading tests were conducted on three scaled specimens of Bujian Puzuo in Yingxian Wooden Pagoda. This study focused on the deformation patterns and analyzed seismic performance under varying scale ratios and vertical loads. The results indicated that the slip and rotational deformations of Bujian Puzuo were the primary deformations. The scale of the specimen did not affect the layer where the maximum interlayer slip occurred, but it did decrease the proportion of slip deformation. Conversely, the reducing vertical load caused the layer with the maximum slippage and the position of the damaged Dou components to shift upward, and the proportion of slip deformation increased. When the vertical load was decreased by 3.7 times, the maximum horizontal bearing capacity under positive and negative loadings, initial stiffness, and energy dissipation of the specimen decreased by approximately 60%, 58.79%, 69.62%, and 57.93%, respectively. The horizontal bearing capacity under positive loading and energy dissipation of the specimen increased by 35.63% and 131.54%, when the specimen scale was doubled and the vertical load was increased by 15 times.

• Structural Engineering and Mechanics
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• 제91권1호
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• pp.25-38
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• 2024

After the mainshock, whether the train can be allowed to pass the bridges plays an important role in ensuring the transport of supplies and rescue works for example, in the "12 May" earthquake in China, after evaluation, the bridge was still used for transportation in rescue at a very slow speed, engineers usually evaluate whether the train can pass the bridge safely based on the experience, lacks sufficient calculation basis and does not fully consider the risk caused by aftershocks. To address this issue, this paper comprehensively considers the randomness of track irregularity, the randomness of aftershock intensity and other multiple random sources in train-bridge interaction system (TBIS). The sensitivity of train to various random parameters after earthquake is analyzed from the perspective of probability, the most sensitive random variable in this paper is PGA of aftershocks, both for bridge and trailer car, With the increase of epicentral distance, the sensitivity of PGA will decrease, and correspondingly, for trailer car, the sensitivity of other random variables will increase, research in this paper provides a basis for the subsequent random analysis of post-earthquake driving safety.

• Smart Structures and Systems
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• 제13권6호
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• pp.993-1014
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• 2014

In civil engineering, revolving structures (RS) are a unique structural form applied in innovative architecture design. Such structures are able to revolve around themselves or along a certain track. However, few studies are dedicated to safety design or health monitoring of RS. In this paper, a wireless dynamic sensing system is developed for RS, and field tests toward a large revolving auditorium are conducted accordingly. At first, a wheel-rail problem is proposed: The internal force redistributes in RS, which is due to wheel-rail irregularity. Then the development of the sensing system for RS is presented. It includes system architecture, network organization, vibrating wire sensor (VWS) nodes and online remote control. To keep the sensor network identifiable during revolving, the addresses of sensor nodes are reassigned dynamically when RS position changes. At last, the system is mounted on a huge outdoor revolving auditorium. Considering the influence of the proposed problem, the RS of the auditorium has been designed conservatively. Two field tests are conducted via the sensing system. In the first test, 2000 people are invited to act as the live load. During the revolving process, data is collected from RS in three different load cases. The other test is the online monitoring for the auditorium during the official performances. In the end, the field-testing result verifies the existence of the wheel-rail problem. The result also indicates the dynamic sensing system is applicable and durable even while RS is rotating.

• 복식
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• 제58권6호
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• pp.12-23
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• 2008

This study reports the costume changes and the factors of the changes from stone status in joseon dynasty. It can be summarized as follows: First, the artisan for the statues is one of the most important factors for the costume changes. The artisans who were involved in building the King's tomb were also made the stone statues for scholars' tombs. This results in that the style of the King's tomb influenced the costumes of stone statues for scholars' tombs. Some craftsmen who were buddhist monks also influenced the introduction of buddhist arts. Second, the stone statues are classified into 3 types according to the dead's social position: the civil officer statues, the military official statues, and the servant statues are installed for the civil officer, the military officers, and others, respectively. This principle was applied well. However, the civil official statues are mainly installed in late joseon dynasty because the civil officers are socially preferred to the military officers in late joseon dynasty. Third, there are two types of civil officer statues; Gongbok type and jobok type. Civil officer statues of Gongbok type were mainly installed in early joseon dynasty and civil officer statues of jobok type were begun to be installed in the early 16th century. Civil officer statues of Gongbok type were fade out after the late 17th century. Fourth, there are three reasons why civil officer statues of jobok type were installed at the officers's tombs 270 years earlier than at the Kings' tombs: 1) Introduction of Daemyunghoejeon and its application, 2) an establishment of a system that requires to prepare jobok individually, and 3) self-confidence of scholars' class on political and cultural maturity.