• Computers and Concrete
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• v.31 no.2
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• pp.123-137
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• 2023

To fully understand shear mechanisms and composite effects of circular concrete-filled steel tube (CFST) columns, systematic numerical investigations were conducted in this paper by improved finite element models. The triaxial plastic-damage constitutive model of the concrete and the interactions between the concrete and steel tube were considered. Afterwards, the critical and upper bound shear span ratios of the circular CFST column under lateral shear loading were determined. The composite effects between the two materials were analyzed by comparing the shear resistance with plain concrete column and hollow steel tube. In addition, a method that predicts the shear bearing capacity of a circular CFST column was proposed. The confining effects on the concrete core and the restraining effects on the steel tube were considered in this method. The proposed formula can predict more accurate results than the methods in different codes and references.

• Journal of architectural history
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• v.29 no.6
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• pp.41-56
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• 2020

This study attempted to clarify the modern transition process of the urban space through the construction and change of the Imperial Palace as a central facility in Seoul. The road renovation of Seoul, which started in 1895, has established a modern, circular transportation system centered on Gyeongun-gung Palace, the Imperial Palace along with the tram line. In this urban structure, the imperial palace as a central facility of the former monarchy, unlike the previous palaces, could not be located at the top of a road with a longitudinal axis, and it expanded its territory around foreign legionaries and placed a new government office around the perimeter. However, the royal palace was moved to Changdeokgung Palace in 1907 with the throne of Sunjong. With the creation of Changdeokgung, which is the periphery of Seoul, as new royal palace, the status of the imperial palace in the city was remarkably weakened, and Gyeongun-gung, located in the center of Seoul, was also reduced to the current Deoksugung area, turning into an urban facility facing a modern street.

• Journal of Power Electronics
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• v.16 no.2
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• pp.542-552
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• 2016

Central 60° synchronous modulation is an easy pulse-width modulation (PWM) method to implement for the traction inverters of urban rail trains at a very low switching frequency. Unfortunately, its switching patterns are determined by a Fourier analysis of assumed steady-state voltages. As a result, its transient responses are not very good with over-currents and high instantaneous torque pulses. In the proposed solution, the switching patterns of the conventional central 60° modulation are modified according to the dynamic error between the target and actual stator flux. Then, the specific trajectory of the stator flux and current vector can be guaranteed, which leads to better system transients. In addition, stator flux control is introduced to get smooth mode switching between the central 60° modulation and the other PWMs in this paper. A detailed flow chart of the control signal transmission is given. The target flux is obtained by an integral of the target voltage. The actual PMSM flux is estimated by a minimum order flux state observer based on the extended flux model. Based on a two-level inverter model, improved rules in the α-β stationary coordinate system and equations of the switching patterns amendment are proposed. The proposed method is verified by simulation and experimental results.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.3
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• pp.65-70
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• 2009

To manage the urban land systematically, it is necessary to analyze the land price annually and correct the problems found by the annual land price analysis. The characteristics of the distribution of the land price and the grip of the central place using GIS can be used as the useful fundamental data for the urban planning and its management mechanism. In this study, the central place measurement, the distribution map and the isarithmic map is analyzed based on the individual notification land price and also its relationship with the central place is analyzed in case study area, Daejeon city.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.11
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• pp.3780-3797
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• 2022

The estimation of radio map (RM) is a fundamental and critical task for the network planning and optimization performance of mobile communication. In this paper, a RM estimation method is proposed based on a deep dual learning structure. This method can simultaneously and accurately reconstruct the urban building map (UBM) and estimate the RM of the whole cell by only part of the measured reference signal receiving power (RSRP). Our proposed method implements UBM reconstruction task and RM estimation task by constructing a dual U-Net-based structure, which is named RadioCycle. RadioCycle jointly trains two symmetric generators of the dual structure. Further, to solve the problem of interference negative transfer in generators trained jointly for two different tasks, RadioCycle introduces a dynamic weighted averaging method to dynamically balance the learning rate of these two generators in the joint training. Eventually, the experiments demonstrate that on the UBM reconstruction task, RadioCycle achieves an F1 score of 0.950, and on the RM estimation task, RadioCycle achieves a root mean square error of 0.069. Therefore, RadioCycle can estimate both the RM and the UBM in a cell with measured RSRP for only 20% of the whole cell.

• Wind and Structures
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• v.31 no.1
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• pp.43-57
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• 2020

Considering the wind barriers induced aerodynamic characteristic variations of both bridge deck and trains, this paper studies the effects of wind barriers on the safety and stability of trains as they run through an urban rail transit cable-stayed bridge which tends to be more vulnerable to wind due to its relatively low stiffness and lightweight. For the bridge equipped with wind barriers of different characteristics, the aerodynamic coefficients of trains and bridge decks are obtained from wind tunnel test firstly. And then, the space vibration equations of the wind-train-bridge system are established using the experimentally obtained aerodynamic coefficients. Through solving the dynamic equations, one can calculate the dynamic responses both the trains and bridge. The results indicate that setting wind barriers can effectively reduce the dynamic responses of both the trains and bridge, even though more wind forces acting on the bridge are caused by wind barriers. In addition, for urban rail transit cable-stayed bridges located in strong wind environment, the wind barriers are recommended to be set with 20% porosity and 2.5 m height according to the calculation results of cases with wind barriers porosity and height varying in two wide ranges, i.e., 10% - 40% and 2.0 m to 4.0 m, respectively.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.4
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• pp.363-372
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• 2000

In order to overtake a quantitative analysis of effect of anthropogenic heat and different land-use on urban thermal environment numerical simulation of surface energy budget was carried out under typical summer synoptic condition. It is beneficial to understand surface temperature of complex urban surace. The different land-use types are classified of rice field farm fruit garden residential region forest water and swamp by using map scaled 1/25000 of Pusan metropolitan. The model predicts that maximum heat island intensity in the central part of Pusan is 7$^{\circ}C$ at 2000 LST in summertime. The surface temperature is propotional to the density of constructions. The effect of anthropogenic heat generation on surface temperature is the increase of 0.3$^{\circ}C$ at 1400LST in the central part of Pusan during summertime.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• no.1
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• pp.219-222
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• 2001

The planning of the central green space (residential park) in a residential quarter is an effective way of increasing public space in the process of urban development and urban renewal. It is regarded as an important technical project in the detail plan of a residential quarter in order to create a better environment in the residential quarters. The scale of a residential park, normally not less than 5000㎡, is defined according to the land-use conditions and the local population. The site should have easy access for the residents, and fit into the surrounding landscape and Fengshui whenever possible. It should also satisfy various leisure needs of the local residents at all ages. The design of the park should be friendly to the residents'interests, hobbies and aspirations. The artistic style of the landscape is to emphasize on delightfulness, harmony and warmness.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6365-6373
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• 2015

Background: Tobacco consumption has become pandemic, and is estimated to have killed 100 million people in the 20th century worldwide. Some 700,000 out of 5.4 million deaths due to tobacco use were from India. The era of global modernization has led to an increase in the involvement of women in tobacco consumption in the low income and middle-income countries. Tobacco consumption by females is known to have grave consequences. Objectives: To assess: (1) the tobacco use among urban and rural women; (2) the discrepancy in the knowledge, belief and behavior towards tobacco consumption among urban and rural women in Durg-Bhilai Metropolitan, Chhattisgarh, Central India. Materials and Methods: The study population consisted of 2,000 18-25 year old young women from Durg-Bhilai Metropolitan, Chhattisgarh, Central India, from both urban and rural areas. Data were collected using a pretested, anonymous, extensive face to face interview by a female investigator to assess the tobacco use among women and the discrepancy in the knowledge, belief and behavior towards tobacco consumption among urban and rural individuals. Results: The prevalence of tobacco use was found to be 47.2%. Tobacco consumption among rural women was 54.4% and in urban women was 40%. The majority of the women from urban areas (62.8%) were smokers whilst rural women (77.4%) showed preponderance toward smokeless tobacco use. Urban women had a better knowledge and attitude towards harms from tobacco and its use than the rural women. Women in rural areas had higher odds (1.335) of developing tobacco habit than the urban women. Conclusions: Increased tobacco use by women poses very severe hazards to their health, maternal and child health, and their family health and economic well-being. Due to the remarkably complex Indian picture of female tobacco use, an immediate and compulsory implementation of tobacco control policies laid down by t he WHO FCTC is the need of the hour.

• Spatial Information Research
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• v.18 no.5
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• pp.63-74
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• 2010

The construction of digital geographic information of Non-Urban Area have been needed to build a nationwide information infrastructure for the balanced development of nation to reduce a gap between city and Non-Urban Area due to the emphasis on a large scale digital map (1/1,000) implementation for cities. In this research, we researched the basic long-term blueprint for establishing digital geographic information in non-urban area. From the proposed institutional foundation, we want to build this information for Non-Urban Areas and to make a long-term plan to strengthen the national com petitiveness dealing with the globalization, liberalization, and information based on the digital geographic information in non-urban area. This study suggested 3 alternatives to implement digital geographic information of Non-Urban Area as follow. Firstly central government fund whole cost, secondly central government and local government fund a cost half and half, lastly combining first and second alternative. This study can be a basis on building national information infrastructure, provide core information for national projects and revitalize the use of spatial information for Non-Urban Area.