• Journal of Environmental Health Sciences
• /
• v.36 no.3
• /
• pp.236-246
• /
• 2010

In preparative anti-corrosive coating experiments, polyaniline was obtained by reacting an oxidizing agent with the monomer aniline. Further, the primer coating was prepared using a variety of widely-used materials such as urethane resin. For the top coating, epoxy resin and acrylic urethane resin were used. Characteristics of the coatings were assessed according to KS and ASTM specifications, and the structure of the polyaniline was characterized using FT-IR and TGA. For analysis of anti-corrosive properties in salt-spray experiments, measurements of the oxidation state of iron and surface atomic analysis were conducted using XPS and SEM-EDX. Unlike general anti-corrosive coatings which exhibit anti-corrosive effects only as a primer coating, the anti-corrosive coatings using polyaniline as the anti-corrosive pigment showed a marked synergistic effect with the top coatings. In other words, the top coatings not only produce a fine view effect, but also increase, through interaction with the primer coatings, the resistance to diffusion of corrosive factors from the external environment. It was also found that, unlike the heavy metal oxide-forming layer of the passive barrier alone, the polyaniline anti-corrosive pigment oxidized iron at the interface with the iron substrate to form a passive barrier in the oxidic layer, and itself formed a potential barrier layer with anti-corrosive factors from the external environment. Although the passive layer was damaged, the damaged area did not become completely oxidized iron; on the contrary, it showed a tendency to reduction. This can be interpreted such that a passive layer is formed again on the damaged area, and that at the same time there is a tendency to self-healing.

• Journal of the Architectural Institute of Korea Planning & Design
• /
• v.35 no.8
• /
• pp.23-34
• /
• 2019

The façade, a fundamental function as a skin that protects human life from external environment such as cold and hot weather, snow, rain, and wind, etc, has served as a media for communication between indoor space of the building and outside space. From the media for communication point of view, the approach to envelope design, in which environmental elements are transmitted internally through the filtering of external environments, has been evolving in various ways from the past to the present. Today, modern architecture technologies including curtain wall systems and user-friendly computer programming and environmental analysis programs demonstrate a differentiated approach to envelope design related to the indoor environment. For this reason, it is worth noting that the envelope design factors and trends that appear variously in the UNStudio's projects before and after the 2000s. The factors reflected in the envelop design in conjunction with the indoor environment obtained through the case study of the UNStudio's office projects were daylight environment, thermal environment, ventilation, noise, privacy and view, and consideration for daylight environment and thermal environment was reflected in many cases through the case study. Looking at the changes in the diagrams in order of year, it can be seen that the envelope design using the environmental analysis tool has been performed since 2006. This is a clue to show the envelop design changes from the conceptual method to the data-based one. The diagrams and analysis results related to the envelop design showed that the thermal environment related to solar radiation was the most, and no diagrams and analysis related to the indoor illumination were found. Since 2010, PV panel installation has been shown in the envelope design, which can be found in the increased efficiency of PV panels due to the technological advances and the decrease in production cost.

• Journal of Korean Society of Water and Wastewater
• /
• v.28 no.6
• /
• pp.647-655
• /
• 2014

To perform long-term sewer monitoring, It is important to understand the nature of the wastewater flow that occurs at the point on early stage of the monitor and to prevent in advance a problem which may caused. We can infer the flow properties and external factors by analyzing the scatter graph obtained from the measured data flow rate monitoring data since an field external factor affecting the sewage flow is reflected in the flow rate monitoring data. In this study, Selecting the three points having various external factors, and we Inferred the sewer flow characteristics from depth-velocity scatter graph and determined the analysis equation for the dry-weather flow rate data. At the'point 1' expected non-pressure flow, we were able to see the drawdown effect caused by the free fall in the manhole section. At the'point 2', existed weir and sediments, there was backwater effect caused by them, and each of size calculated from the scatter graph analysis were 400 mm and 130 mm. At the'Point 3', there is specific flow pattern that is coming from flood wave propagation generated by the pump station at upstream. In common, adequate equations to explain the dry weather flow data are flume equation and modified manning equation(SS method), and the equations had compatibility for explaining the data because all of $R^2$ values are over 0.95.

• Journal of the Korean GEO-environmental Society
• /
• v.12 no.12
• /
• pp.13-20
• /
• 2011

The main objective of this paper is finding the influence factors and their degree of importance to steel liner's safety by investigating and evaluating the buckling incidents of steel tunnel liner under external water pressure. The study was based on the detailed investigation to the design conditions and incident shapes at 2m diameter waterway tunnel with a partially buckled internal steel liner and concrete backfilled lining as the raw water transmission pipe line of regional water supply project. Appropriate buckling theory capable of applying this incident points was selected by referring the existing literature and compared with the results of investigation. Also, hydrogeological characteristics of this site on buckling pressure was evaluated. The result of this study was shown that both the hydrogeological characteristics of upper geologic layers and proper tunnel construction are important factors on buckling at steel liner, and hydraulic gradient level should be decided according to the hydrogeological characteristics. This incident case analysis on steel liner of pressurized waterway tunnel was expected to provide more information for realizing the problems and improvements at each design, construction and maintenance stages.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
• /
• v.6 no.6
• /
• pp.395-402
• /
• 2016

Recently, firms confront to rapid environmental changes due to scientific development and demand change. Firms are trying to improve supply chain capability to react these environmental changes. Being in these improvement processes, it is important to collaborate with other partners in the supply chain. Firms have tried to outsource their in-house activity to other partners and have eliminated wasteful factors in their process and the supply chain is getting leaner. This study investigates the effect of waste factor degree on supply chain performance under external risks. Test results in this paper show that waste level has negative relationship with supply chain performance. The effect of waste level on the supply chain performance is influenced by external risk. As waste level increases, risk has moderating effect between waste level and supply chain performance. That means it is important to focus on utilization, productivity or integration properly for managing the external risk in order to improve the supply chain performance.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.20 no.7
• /
• pp.15-24
• /
• 2021

In this paper, to analyze the types of surface morphology error according to factors that cause machining error, the experiments were conducted in the ultra-precision diamond machine using a diamond tool. The factors causing machining error were classified into the pressure variation of compressed air, external shock, tool errors, machining conditions (rotational speed and feed rate), tool wear, and vibration. The pressure variation of compressed air causes a form accuracy error with waviness. An external shock causes a ring-shaped surface defect. The installed diamond tool for machining often has height error, feed-direction position error, and radius size error. The types of form accuracy error according to the tool's errors were analyzed by CAD simulation. The surface roughness is dependent on the tool radius, rotational speed, and feed rate. It was confirmed that the surface roughness was significantly affected by tool wear and vibration, and the surface roughness of Rz 0.0105 ㎛ was achieved.

• The Journal of the Korea Contents Association
• /
• v.18 no.1
• /
• pp.132-142
• /
• 2018

This study attempts to identify the external and internal factors which affect collaboration motives and investigates their respective impacts from the perspective of foreign direct investment(FDI). Although there has been much research on collaboration motives, so far, few studies have associated collaboration motives with FDI. The findings suggest that while price competitiveness and cost structure uncertainty have a positive and significant impact on collaboration motives, the gross added value to property as well as plant and equipment have a significant negative impact. Furthermore, in the case of gross added value to both property and plant and equipment, managers tend to collaborate with others to enhance the value of these factors. For both FDI and non-FDI firms, internal factors such as price competitiveness and investment within three years are significant determinants for the decision to collaborate. The difference between FDI and non-FDI firms is that for the former, the gross added value to property, an internal factor, is a critical factor, while for the latter, the cost structure uncertainty, an external factor, is critical for collaboration. To summarize, this study suggests the following managerial implication: the enhancement of the internal competency of a firm broadens the window of opportunity for collaboration with others, and consequently provides a chance to boost management efficiency.

• Journal of the Korean Institute of Rural Architecture
• /
• v.18 no.2
• /
• pp.39-46
• /
• 2016

The purpose of this study was to analyze the preferences for the physical features of return farmer housing. Housing problems of rural areas is one of the important factors that determine the quality of life in rural areas. Through these return farmer housing as it wants to improve the living environment of rural areas. The purpose of this study aims to find the required characteristics of the return farmer for rural activation. The survey was conducted to target the return farmer households living in housing and expectant return farmer living in the rural. The results of this study were as follows. First, expectant return farmer than return farmer are more importance to house outside(environmental) factors. Showed that environmental conditions are more important than housing conditions, expectant return farmer of residential satisfaction. Second, return farmer prefer ratio was higher House prices and sizes, expectant return farmer among the external factors such as environmental conditions is the distance to the workplace were very important. The results of this study can be a basis for effective strategies for future rural activation. More sustainable in the future, including the analysis of various parameters in progress by being linked to policy measures that will be provided. This study aims to be the foundation of sustainable housing policies for return farmer households.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.35 no.6
• /
• pp.548-558
• /
• 1990

Physiology and genetics of early maturity in cereals are the subject of practical as well as scientific interest for agronomist and plant breeders, Thorough understanding of the true nature of such a complex character requires physiological and genetical knowledge about the internal factors, which are closely bound up with and react to some particular external or environmental factors. From the practical point of view. experiments should be conducted under controlled conditions. especially the day length and temperature, so that the genotypic differences pertaining to these factors may be discerned. Takahashi and Yasuda (1958, 1970) maintained that at least three physiological factors were responsible for determining earliness in barley. namely. (1) spring and winter habit of growth or vernalization requirement, (2) ogitioeruiduc response or sensitivity to short-day, and (3) earliness factor in a narrow sense or minimal vegetative growth. The same situations were true in common wheat also (Yasuda and Shimoyama, 1965), In this report. physiology and genetics of internal factors and their relations to the time of heading in the field will be presented with some problems concerning differences in mechanism of early maturity between barley and wheat.

• Journal of Convergence for Information Technology
• /
• v.9 no.7
• /
• pp.67-77
• /
• 2019

Many small and medium-sized enterprises are deploying Smart Factory without due consideration of the circumstances in which the entity is in or outside of the entity, such as environmental changes and the capabilities of its members. Therefore, utilization and effectiveness are also low after deployment. This study verifies 'the establishment of a Smart Factory through the environmental factors and absorption capabilities of small businesses' through empirical research. The survey was received by people working for small and medium-sized companies that have established Smart Factory. The results of the study showed that first, environmental factors within and outside the company had a positive effect on the absorption capacity within the company. Second, the absorption capacity within a company has had a positive effect on the deployment of a Smart Factory. Based on the above proof, it has been proved to be effective if the core areas of the Smart Factory are built on the basis of the company's internal and external environmental factors and absorption capabilities when constructing Smart Factory in small businesses. In the future, we will study the achievements of smart factory construction.