• Journal of Urban Science
• /
• v.9 no.1
• /
• pp.41-49
• /
• 2020

This study analyzed the factors affecting economic growth using multiple regression model and Geographically Weighted Regression in consideration of population, industry and employment, housing and political characteristics on economic growth by region. The analysis results are summarized as follows. First, the total employment growth rate, manufacturing employment growth rate, local election turnout and the level of party consensus between the central and local governments are having a positive impact on regional economic growth. Second, according to the GWR analysis, the population has a positive impact on economic growth in the southern region of Korea, and the increase in the total number of employees has a positive impact on the southern region of Gyeonggi Province, Gangwon Province, North Chungcheong Province and North Gyeongsang Province. Finally, the voter turnout of urbanites is positively affecting economic growth in South Chungcheong Province, Gangwon Province and the southern coast, while North Jeolla and South Jeolla provinces have a positive impact on economic growth as the parties of the central and local governments are equal. The results of this study may suggest the role of local government for regional economic development.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.19 no.7
• /
• pp.1-6
• /
• 2020

Micro-structure components applied to various disciplines are steadily demanded with lighter weight and better quality. This is because that ultra thin-wall injection molding has been paid attention with a lot of benefits such as cost reduction, shorter process period, and so forth. However, this technology is complicate and difficult to obtain high quality of products compared with conventional injection molding due to warpage caused by uneven shrinkage and molecular orientation. Since warpage of products directly affects product quality and overall performance of devices, it is essential to predict deformation behavior to achieve high precision of molded products. Therefore, this study aims to find out adequate thin-wall mold design for FPC connector housing by employing Moldflow simulation before application. In addition, experimental research is performed by using a fabricated mold structure based on simulated results to prove accuracy and reliability of the suggested simulation for warpage analysis.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2016.05a
• /
• pp.189-190
• /
• 2016

Lightweight concrete is currently used at apartment buildings or housing construction sites causes some uneconomical problems due to excessive cracks and subsidences. So, it is in the situation that it is necessary to set up countermeasures against such subsidences. Therefore, in this study, it is intended to analyze the prevention of a subsidence inducing the expansion of the aluminum components depending on the changes of substitution rate and bubble mixing ratio by using the bubble-based Leavening Agent that Aluminum slag as an industrial by-product is substituted into some desulfurized plaster. As the results, it was found that the blending ratios, such as, the substitution ratio of bubble-based leavening agent (1%) and the bubble mixing ratio (65%) are appropriate while the flow property, subsidence depth and compression strength are considered.

• Elastomers and Composites
• /
• v.44 no.4
• /
• pp.366-372
• /
• 2009

The present study covers the optimal design for a lens module in a mobile phone camera by using the design of experiments (DOE) and finite element (FE) analysis. FE analyses are performed to investigate the effect of design parameters on the amount of torque required to assemble a barrel and a housing part. The DOE approach is then performed to optimize the design parameters in order to maintain an appropriate torque with less variations.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.16 no.6
• /
• pp.153-158
• /
• 2017

Reducer is a device to transmit and change torque and speed from drive shaft to driven shaft with excellent transmission efficiency, and it is widely used in many areas today. Reduction gear consists of two axes, gear, bearing supporting axes, and housing. The simplest method to transmit rotation or power to multiple axes is to attach circular plates to two axes and contact each other. However, in this case, if increasing number of rotations or if contact pressure is small, because of slipping, it cannot transmit power. For problems for the current reducer case, it is heavy and its assembling and repair is difficult. In addition, there are few studies about manufacturing and performance testing of worm gear reducer, causing lack of the foundation to improve the product competition and the performance.

• Journal of Families and Better Life
• /
• v.2 no.1
• /
• pp.165-177
• /
• 1984

The purpose of this study was to investigate satisfaction with the function of interior space of apartment and factor which influence it, and then to provide housing practitioners with basic data for more desirable apartment interior environment. On the basis of the review of literature, questionnaire was developed. The sample was classified into type of unit floor plan and house size of 17 districts in Seoul. 139 households were selected in three districts which were the first three regions of high apartment density. Data were analyzed by computer using frequency, percentage, mean, standard deviation, F-test, Duncans multiple range test, η2 , person's product moment correlation coefficient. the results are as follows: Factors which influence satisfaction with the functionality of interior were household size and family life cycle as sociodemographic variable, and type of unit floor plan as physical variable. It was shown that the satisfaction with the functionality of interior was related to satisfaction with the external environment. More specifically, (1)the smaller a household size was the more the owner became satisfied. (2)households were in the stage of establishment in the family life cycle and households with C type of unit floor plan showed higher degree of satisfaction. (3) satisfaction with the functionality of interior had positibly related to satisfaction with the external environment.

• Design & Manufacturing
• /
• v.13 no.2
• /
• pp.44-48
• /
• 2019

Motor core products are used as materials for electrical steel sheets and cold-rolled steel sheets according to the performance of motors. The cemented carbide material of the mold punch applied to the motor core material causes many troubles due to abrasion and burr problem. The selection of these materials has a great effect on the production life, mass production, product quality as well as mold life. The cemented carbide applied to the products of the motor core is recognized as a very important part. In this study, cold rolled steel sheet was applied to motor core SCP-1 steel 1.0mm, and The effects of abrasion and punching oil on the shear process were investigated for the selection of cemented carbide. Experiments were conducted to select and apply cemented carbide only for the motor core punch optimized for cold rolled steel. The results showed that the cemented carbide material of $CDK3^{***}$ produced the least wear and burrs.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2021.05a
• /
• pp.53-54
• /
• 2021

Grenfell Tower was renovated in 2014 and 2016 at a high cost to replace the exterior materials, windows and co-heating facilities of the building. The exterior materials used during the repair work were sandwich panels filled with polyethylene and plastic, which were expanded on the aluminum metal surface. It is a product called Celotex RS 5000, a low-resolution but inexpensive repair material, and is currently an external material that cannot be used in high-rise buildings. Similar domestic fire cases began to focus social attention on the safety of high-rise buildings through the Busan Residential Complex Fire (2010), Uijeongbu Urban Living Housing Fire (2015), and Ulsan Residential Complex Fire (2020), and residents' safety concerns are increasing. In Korea, the occurrence and risk of similar fires are high, so setting up fire prevention measures through fire case investigation is considered the most basic measure in securing human safety. Therefore, the purpose of this study is to examine the status of fire damage caused by domestic and foreign eruptions, domestic and international research status and related regulations on external materials and windows starting from the Grenfell Tower fire in England.

• Geomechanics and Engineering
• /
• v.31 no.3
• /
• pp.281-289
• /
• 2022

Bio-CaCO₃ is a blowout environment-friendly materials for soil improvement and sealing of rock fissures. To evaluate the chemical characteristics, shape, size and productivity of soybean urease induced CaCO₃ precipitates (SUICP), experimental studies were conducted via EDS, XRD, FT-IR, TGA, BET, and SEM. Also, the conversion rate of SUICP reaction at different time were determined and analyzed. The Bio-CaCO₃ product obtained by SUICP is comprehensively judged as calcite based on the results of EDS, XRD and FT-IR. The SUICP calcite precipitates are detected as spherical or ellipsoidal particles 3-6 ㎛ in diameter with nanoscale pores on their surface, and this morphology is novel. The median secondary particle size d₅₀ is 39-88 ㎛, indicating the agglomeration of the primary calcite particles. The Bio-calcite decomposes at 650-780℃, representing a medium thermal stability. The conversion rate of SUICP reaction can reach 80% in 24h, which is much more efficient than microbially induced CaCO₃ precipitation. These results reveal the knowledges of SUICP, and further direct its engineering applications. Moreover, we show an economic channel to obtain porous spherical calcite.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.13 no.3
• /
• pp.37-46
• /
• 2018

This paper define the research problem as the jeopardized situation of most startups in early chasm. Korean government have put more policy focus on helping these startups to jump over the chasm. One of the effective policy measures helps these startups defining the core competencies validated from target customers, in-housing them effectively, and therefore enhancing the level of differentiation against the competitors by "Product Pivoting Training Boots Camp." It ultimately give the key nudge to startups in struggling with unsold products after initial launch to the market. This paper carried out the empirical test to the target sample of startups participating in this camp. In particular, this research analyze the level of satisfaction of startups, as move along with characteristics of the participant and training program, going through this camp whether it enhance their will of application into real business case. The survey were delivered and collected from 203 startups in attending "Product Pivoting Academy, the following program of Startup Jump-up package policy module. The research result shows that all startups participating in this academy were so much satisfied and motivated strongly to take the training process into applying real business case in order to increase sales. The quality of the training program and the characteristics of the participants had mediating variable effects on the will of application with respect to the level of satisfaction. It imply that the program should put more attention on improving coaches' nudge and learning motivation of participants to enhance the level program satisfaction.