• Title/Summary/Keyword: modification factor

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A Fluid Analysis Study on Centrifugal Pump Performance Improvement by Impeller Modification (원심펌프 회전차 Modification시 성능개선에 관한 유동해석 연구)

  • Lee, A-Yeong;Jang, Hyun-Jun;Lee, Jin-Woo;Cho, Won-Jeong
    • Journal of the Korean Institute of Gas
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    • v.24 no.2
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    • pp.1-8
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    • 2020
  • Centrifugal pump is a facility that transfers energy to fluid through centrifugal force, which is usually generated by rotating the impeller at high speed, and is a major process facility used in many LNG production bases such as vaporization seawater pump, industrial water and fire extinguishing pump using seawater. to be. Currently, pumps in LNG plant sites are subject to operating conditions that vary depending on the amount of supply desired by the customer for a long period of time. Pumps in particular occupy a large part of the consumption strategy at the plant site, and if the optimum operation condition is not available, it can incur enormous energy loss in long term plant operation. In order to solve this problem, it is necessary to identify the performance deterioration factor through the flow analysis and the result analysis according to the fluctuations of the pump's operating conditions and to determine the optimal operation efficiency. In order to evaluate operation efficiency through experimental techniques, considerable time and cost are incurred, such as on-site operating conditions and manufacturing of experimental equipment. If the performance of the pump is not suitable for the site, and the performance of the pump needs to be reduced, a method of changing the rotation speed or using a special liquid containing high viscosity or solids is used. Especially, in order to prevent disruptions in the operation of LNG production bases, a technology is required to satisfy the required performance conditions by processing the existing impeller of the pump within a short time. Therefore, in this study, the rotation difference of the pump was applied to the ANSYS CFX program by applying the modified 3D modeling shape. In addition, the results obtained from the flow analysis and the curve fitting toolbox of the MATLAB program were analyzed numerically to verify the outer diameter correction theory.

The Development of National Competency Standard(NCS) Regarding Casino Operations Management (카지노운영관리 직무에 관한 국가직무능력표준(NCS) 개발)

  • Kim, Dong-Yeon;Oh, Seung-Gyun;Koo, Ja-Gil;Kim, Jinsoo
    • 대한공업교육학회지
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    • v.39 no.1
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    • pp.143-163
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    • 2014
  • This study developed a National Competency Standard(NCS) regarding the casino operations management based on the manual for developing National Competency Standard of 13 years and a revised classification system chart of the National Competency Standard. For the research method, this study developed a national competency standard of relevant jobs after going through review, consultation, modification, supplementation, and reporting procedures 10 times with development experts of the National Competency Standard, the industrial setting professionals, education and training experts, qualification(job analysis) experts, facilitators, and a working group of job verification committee based on the phased range and DACUM procedure of study. The major development results of this study are as follows. First, this study selected and defined duties based on the revised classification system chart of the National Competency Standard, then drew and developed total 8 ability units based on the applicable duties. Secondly, based on the developed ability units, total 27 ability unit factors were deduced and developed. Thirdly, a standard system by ability unit factor was developed based on the level of the national competency standard and revised classification system chart, then this study deduced and developed a supra-domain of the standard system by competency units using the standard tranquility value by these competency unit factors. Based on such development contents and guidelines for the national competency standard ability unit classification number, this study deduced and developed category numbers by relevant competency unit. Fourthly, total 27 relevant performance standard by competency units and knowledge, skill, and attitude were deduced and developed. Fifthly, this study deduced and developed a scope of application, work situation, evaluation guide, core competency, and development history in reference to the total 8 relevant competency units based on the duties.

A Study on the Cause Analysis and Countermeasures of the Traditional Market for Fires in the TRIZ Method (TRIZ 기법에 의한 재래시장 화재의 원인분석과 대책에 관한 연구)

  • Seo, Yong-Goo;Min, Se-Hong
    • Fire Science and Engineering
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    • v.31 no.4
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    • pp.95-102
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    • 2017
  • The fires in the traditional markets often occur recently with the most of them expanded into great fires so that the damage is very serious. The status of traditional markets handling the distribution for ordinary people is greatly shrunk with the aggressive marketing of the local large companies and the foreign large distribution companies after the overall opening of the local distribution market. Most of the traditional markets have the history and tradition from decades to centuries and have grown steadily with the joys and sorrows of ordinary people and the development of the local economy. The fire developing to the large fire has the characteristics of the problem that the fire possibility is high since all products can be flammable due to the deterioration of facilities, the arbitrary modification of equipment, and the crowding of the goods for sale. Furthermore, most of the stores are petty with their small sizes so that the passage is narrow affecting the passage of pedestrians. Accordingly, the traditional markets are vulnerable to fire due to the initial unplanned structural problem so that the large scale fire damage occurs. The study is concerned with systematically classifying and analyzing the result by applying the TRIZ tool to the fire risk factors to extract the fundamental problem with the fire of the traditional market and make the active response. The study was done for preventing the fire on the basis of it and the expansion to the large fire in case of fire to prepare the specific measure to minimize the fire damage. On the basis of the fire expansion risk factor of the derived traditional market, the study presented the passive measures such as the improvement of the fire resisting capacity, the fire safety island, etc. and the active and institutional measures such as the obligation of the fire breaking news facilities, the application of the extra-high pressure pump system, the divided use of the electric line, etc.

A Study on the Decline of Provincial Government Office of Jeollabuk-do in Modern Era (근대기 전라북도 지방관아의 쇠퇴에 관한 연구)

  • Oh, Jun-young;Kim, Young-mo
    • Korean Journal of Heritage: History & Science
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    • v.48 no.1
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    • pp.24-43
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    • 2015
  • This study constitutes an inquiry into the decline of Government Office(官衙) facilities carried out intensively during modern era, focusing on provincial government offices of Jeollabuk-do. There have been several studies of changes in provincial government offices till now, but there have been few studies of government offices of the counties and prefectures(郡縣) during the period of the Japanese Resident-General of Korea and after the National Liberation, temporally and there have still been lacking studies on Jeollabuk-do, spatially. Thus, this study attempts to empirically prove the reasons and the time of the decline of provincial government offices in Jeollabuk-do and the characteristics in the process of decline focusing on modern era. As a result of the study, four factors: demolition, abolition, appropriation and disaster had the most decisive impacts on the decline of government office facilities. Demolition refers to the destruction of government office facilities, and abolition, to the decline and the discontinuation of the operation of the facilities. Appropriation refers to conversion to facilities to meet public functions, and disaster, damage from a typhoon or fire. These factors had already been started from the 1900s, and by the 1930s, most of the government office facilities came to lose their original looks and functions. In the meantime, there was an essential purpose in demolition, the most direct factor in the destruction of the government office facilities in terms of function: that is new construction of public facilities necessary for administration and rule. The existing government office facilities were appropriated, sometimes, but behind that, many cases of demolition of the government office facilities for the new construction of public facilities are found. The appropriation of the government office facilities is divided into educational, administrative, financial and security facilities, and generally, Gaeksa(客舍) and Dongheon(東軒) were used respectively as educational and administrative facilities while their attached facilities were used as financial and public order and security facilities in general. Especially, some government office facilities were utilized as distinctive facilities such as housing or hospital. In the process of appropriation, a lot of modification occurred inside and outside the government office facilities, due to which, the government office facilities gradually declined losing their traditional styles.

The Effect of Participation Degree in Sports for all of People with Physical Disabilities on Positive Psychological Capital(PPC) (지체장애인의 생활체육 참여정도가 긍정심리자본(PPC)에 미치는 영향)

  • Kim, Dae-Kyung;Park, Jin-Woo;Kim, Hye-Min;Lee, Hyun-Su
    • 한국체육학회지인문사회과학편
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    • v.54 no.5
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    • pp.867-876
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    • 2015
  • This study was intended to closely examine an effect that the level of physically challenged person's participation in community sports had on positive psychological capital. In order to accomplish the purpose of study, data on 212 physically challenged persons who lived in B city and participated in community sports were analyzed. Korean version of positive psychological capital created by Taehong Lim (2014) through the reconstruction of scales developed by Luthans, Youssef and Avolio(2007) and Sangwan Jeon and Jonghun Yang's (2009) level of participation in community sports was reconstructed through modification·improvement as measurement instrument. An exploratory factor analysis, reliability test, paired difference test, and multiple regression analysis was carried out by using SPSS 18.0 program for data processing. First, It was shown that there was a significant difference in positive psychological capital according to gender, age, and disability grade among physically challenged persons' socio-demographic characteristics. Second, it was shown that, among sub-variables (period, frequency and intensity) of level of physically challenged persons' participation in community sports, the frequency of participation and the intensity of participation had a significant effect on self efficacy. On the other hand, it was shown that the period of participation didn't have a significant effect. Third, it was shown that the frequency of participation had a significant effect on optimism. On the other hand, it was shown that the period of participation and the intensity of participation didn't have a significant effect. Fourth, it was shown that the frequency of participation and the intensity of participation had a significant effect on hope. On the other hand, it was shown that no significant effect was produced on the period of participation. Fifth, it was shown that the frequency of participation had a significant effect on resilience. On the other hand, it was shown that no significant effect was produced on the period of participation and the intensity of participation. Sixth, it was shown that the frequency of participation and the intensity of participation had a significant effect on positive psychological capital. And it was shown that no significant effect was produced on the period of participation.

Remodeling and Damage of the Garden According to the Park Project in Deoksugung Palace During the Japanese Colonial Period (일제강점기 덕수궁(德壽宮) 공원화에 따른 정원의 개조와 훼손)

  • OH Junyoung
    • Korean Journal of Heritage: History & Science
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    • v.56 no.3
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    • pp.234-252
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    • 2023
  • This study looked at the modification of major gardens while making Deoksugung Palace (德壽宮) a park in the Japanese colonial era. This is because landscaping work was carried out in various places from 1932 to 1933 to open Deoksugung Palace, which used to be an imperial palace, as a public recreation space. In particular, major gardens such as the front yard of Seokjojeon Hall (石造殿), the back yard of Hamnyeongjeon Hall (咸寧殿), and the back yard of Jeukjodang Hall (卽阼堂) were greatly transformed into different shapes from the original. During the first phase of construction in 1932, a water tank was installed in Seokjojeon Hall Garden, creating the first water space. This water tank was originally a structure installed in the front yard of Injeongjeon Hall (仁政殿) of Changdeokgung Palace (昌德宮). Around 1909, a water tank installed in the front yard of Injeongjeon Hall was relocated to Seokjojeon Garden in the process of turning Deoksugung Palace into a park. The water tank moved from the front yard of Injeongjeon Hall was a factor that transformed the central area of Seokjojeon Garden into a water space, and a fountain installed to replace the water tank remains to this day. The backyard of Hamnyeongjeon Hall was also renovated into a new shape during the first phase of construction. Originally, there was a terraced flowerbed called Hwagye (花階) in the backyard of Hamyujae Hall (咸有齋) and Hamnyeongjeon Hall, and it was restored from the construction that took place after the Great Fire of Deoksugung Palace. In the process of turning Deoksugung Palace into a park, a three-stage stonework was built in the front yard of Jeonggwanheon Pavilion (靜觀軒) which renovated the Hwagye in the backyard of Hamyujae Hall and Hamnyeongjeon Halll. The stonework built at that time was used as a peony garden to provide visitors with attractions after the opening of Deoksugung Palace, and it remains today with the name Jeonggwanheon's Hwagye. The backyard of the Jeukjodang Hall area is a case of damage in the second phase of construction in 1933. Like the backyard of Hamnyeongjeon Hall, the backyard of Jeukjodang Hall, where the Hwagye was originally built, was converted into a Japanese-style garden in the process of turning Deoksugung Palace into a park. The site where the Hwagye was demolished was decorated with a Japanese-style garden centered on mounding, small roads, and landscaping stones, as well as topographic control and planting work. Although there have been minor changes since liberation, the backyard of the Jeukjodang Hall area is still based on a Japanese-style garden created by turning Deoksugung Palace into a park.