• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.4
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• pp.167-173
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• 2005

Thermal regeneration means burning-off and cleaning-up the particulate matters piled up in DPF(diesel particulate filter), and it requires both high temperature $(550\~600^{\circ}C)$ and appropriate concentration of oxygen at DPF entrance. However, it is not easy to satisfy such conditions because of the low temperature window of the HSDI(high speed direct injection) diesel engine(approximately $200\~350^{\circ}C$ at cycle). Therefore, this study is focused on the method to raise temperature using the trade-off relation between temperature, oxygen concentration, and the influence of many parameters of common rail injection system including post injection. After performing an optimal mapping of the common rail parameters for regeneration mode, the actual cleaning process during regeneration mode is investigated and evaluated the availability of the regeneration mode mapping through regenerating soot trapped in the DPF.

• MISULJARYO - National Museum of Korea Art Journal
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• v.101
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• pp.12-46
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• 2022

Completed in 1467, the Thirteen-story Stone Pagoda of Wongaksa Temple is the last Buddhist pagoda erected at the center of the capital (present-day Seoul) of the Joseon Dynasty. It was commissioned by King Sejo, the final Korean king to favor Buddhism. In this paper, I aim to examine King Sejo's intentions behind celebrating the tenth anniversary of his enthronement with the construction of the thirteen-story stone pagoda in the central area of the capital and the enshrinement of sarira from Shakyamuni Buddha and the Newly Translated Sutra of Perfect Enlightenment (圓覺經). This paper provides a summary of this examination and suggests future research directions. The second chapter of the paper discusses the scriptural background for thirteen-story stone pagodas from multiple perspectives. I was the first to specify the Latter Part of the Nirvana Sutra (大般涅槃經後分) as the most direct and fundamental scripture for the erection of a thirteen-story stone pagoda. I also found that this sutra was translated in Central Java in the latter half of the seventh century and was then circulated in East Asia. Moreover, I focused on the so-called Kanishka-style stupa as the origin of thirteen-story stone pagodas and provided an overview of thirteen-story stone pagodas built around East Asia, including in Korea. In addition, by consulting Buddhist references, I prove that the thirteen stories symbolize the stages of the practice of asceticism towards enlightenment. In this regard, the number thirteen can be viewed as a special and sacred number to Buddhist devotees. The third chapter explores the Buddhist background of King Sejo's establishment of the Thirteen-story Stone Pagoda of Wongaksa Temple. I studied both the Dictionary of Sanskrit-Chinese Translation of Buddhist Terms (翻譯名義集) (which King Sejo personally purchased in China and published for the first time in Korea) and the Sutra of Perfect Enlightenment. King Sejo involved himself in the first translation of the Sutra of Perfect Enlightenment into Korean. The Dictionary of Sanskrit-Chinese Translation of Buddhist Terms was published in the fourteenth century as a type of Buddhist glossary. King Sejo is presumed to have been introduced to the Latter Part of the Nirvana Sutra, the fundamental scripture regarding thirteen-story pagodas, through the Dictionary of Sanskrit-Chinese Translation of Buddhist Terms, when he was set to erect a pagoda at Wongaksa Temple. King Sejo also enshrined the Newly Translated Sutra of Perfect Enlightenment inside the Wongaksa pagoda as a scripture representing the entire Tripitaka. This enshrined sutra appears to be the vernacular version for which King Sejo participated in the first Korean translation. Furthermore, I assert that the original text of the vernacular version is the Abridged Commentary on the Sutra of Perfect Enlightenment (圓覺經略疏) by Zongmi (宗密, 780-841), different from what has been previously believed. The final chapter of the paper elucidates the political semantics of the establishment of the Wongaksa pagoda by comparing and examining stone pagodas erected at neungsa (陵寺) or jinjeonsawon (眞殿寺院), which were types of temples built to protect the tombs of royal family members near their tombs during the early Joseon period. These stone pagodas include the Thirteen-story Pagoda of Gyeongcheonsa Temple, the Stone Pagoda of Gaegyeongsa Temple, the Stone Pagoda of Yeongyeongsa Temple, and the Multi-story Stone Pagoda of Silleuksa Temple. The comparative analysis of these stone pagodas reveals that King Sejo established the Thirteen-story Stone Pagoda at Wongaksa Temple as a political emblem to legitimize his succession to the throne. In this paper, I attempt to better understand the scriptural and political semantics of the Wongaksa pagoda as a thirteen-story pagoda. By providing a Korean case study, this attempt will contribute to the understanding of Buddhist pagoda culture that reached its peak during the late Goryeo and early Joseon periods. It also contributes to the research on thirteen-story pagodas in East Asia that originated with Kanishka stupa and were based on the Latter Part of the Nirvana Sutra.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.670-673
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• 2007

In Korea, it has recently occurred that problems of productivity and construction duration in the construction industry. If five days per week system come into effect, they'll become more urgent. The productivity of construction industry and competitive construction duration in Korea are too low. If post sale system becomes effective, construction companies will strive to improve productivity. Therefore, the objective of this study is to draw up Architectural PC as the alternative for productivity improving and analyze possibility of productivity improving by comparing with established method of construction.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.7
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• pp.884-891
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• 2016

A secondary injection system in a diesel engine has benefits: it can be controlled independently without interrupting engine control, it can be adapted to various layouts for exhaust systems, and it pose no reductant dilution problems compared to post injection systems in the combustion chamber or other supplemental reductant injections. In a secondary injection system, the efficiency of the catalyst depends on the method of reducing the supply. The reductant needs to be maintained and optimized with constant pressure, the positions and angles of injector is a very important factor. The concentration and amount of reductant can be changed by adjusting secondary injection conditions. However, secondary injection is highly dependent upon the type of injector, injection pressure, atomization, spray technology, etc. Therefore, it is necessary to establish injection conditions the spray characteristics must be well-understood, such as spray penetration, sauter mean diameter, spray angle, injection quantity, etc. Uniform distribution of the reductant corresponding to the maximum NOx reduction in the DeNOx catalyst system must also assured. With this goal in mind, the spray characteristics and impingement plate types of a secondary injector were analyzed using visualization and digital image processing techniques.

• Korean Journal of Construction Engineering and Management
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• v.7 no.2 s.30
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• pp.109-117
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• 2006

Recent rapid changes such as construction market reduction, lowest bidding system of construction cost, five days per week system, and post-construction sale system are inevitably accelerating the competitiveness between construction companies. Those rapid changes of construction environment require construction companies, which are main participants of construction industry, to adapt to the changes and more to lead new construction environment. However, there are many construction uncertainties which could delay construction completion. Without the proper identification of construction uncertainties, structured strategy establishment and management of construction schedule, the competitive advantages of construction duration could not be made. Thus this paper limited the research boundary to construction duration competitiveness instead of general strategy establishment. Recognizing the importance of proper calculation of construction duration, requirements of construction duration reduction and limited researches related to construction schedule strategy, we established the 25 strategies for construction duration competitivenss by internal and external construction environment analysis and SWOT analysis, and then elicited the first considerations to accomplish the strategies through concensus of all the staffs by questionnaire, brainstroming and face-to-face interviews.

• Korean Journal of Construction Engineering and Management
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• v.7 no.1 s.29
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• pp.138-147
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• 2006

Construction companies have been interested in the construction duration which importantly affects the performance and the success of the construction projects in accordance with the systemic changes such as five days per week system, introduction of construction duration reduction bidding system and post sale system nowadays. It is also very important to estimate and forecast properly the construction duration as the construction companies compete for the projects in the situation of construction market reduction and the lowest bidding system. Recognizing the importance about the construction duration, the researches about comparing and analyzing or estiamting the construction duration have been performed. However, comparing studies about the construction duraion have been limited to the apartment and office building in domestic area. Many studies about forecasting construction duration have been performed through stochastic analysis and simulations. Little research has been addressed the comparison analysis of the real construction duration about the mix-use building and officetel building which occured according to the changes of the building requirements. Therefore, the objective of this study is to compare and analyze the real construction duration and the hypothetical construction duration about the mix-use building and officetel building of the domestic companies. Moreover, we select the most competitve construction company to get the strengths and analyze the competitive advatages of the construction companies about construction duration.