The theoretical investigation has been performed to predict thermodynamic stability, density, detonation velocity, and detonation pressure of energetic salts produced by pairing of nitrogen-rich anions (tetrazine, oxadiazole etc.) and cations (NH3OH+, NH2NH3+, CH9N6+, C2H6N5+). All possible geometries and the binding energy for the trigger bond of energetic salts have been optimized at the B3LYP/cc-pVDZ level of theory. The detonation velocity and detonation pressure have been calculated using Kamlet-Jacobs equation, while enthalpy has been predicted at the G2MP2 level of theory. The predicted results reveal that the energetic salts including small sized NH3OH+(1) and NH2NH3+(2) cations increase detonation property. And also the energetic salts including more amino group (-NH2) such as CH9N6+(3) cation increase thermodynamic stability. These results provide basic information for the development the high energy density materials (HEDMs).
The purpose of this project was to improve the stability of a pair of leather socks for use on snowy days in the collection of the National Museum of Korea (Namsan1567) by conducting conservation treatment and restoring the socks to their original form for use in research and exhibition. Leather socks are referred to in ancient documents with names combining the word "mal" for socks with a term indicating their material (e.g., pimal, meaning leather socks; nokpimal, meaning deer leather socks; jangpimal, meaning roe deer leather socks, or lipimal, meaning racoon dog leather socks) and are mentioned mostly in connection with Jeju Island. Related documents include the Seungjeongwon ilgi (Daily Record of the Grand Secretariat), Injaeilnok (Diary of Injae Jo Geukseon), and Hamel's Journal and a Description of the Kingdom of Joseon. Extant examples of ancient leather socks display the same form as beoseon (traditional Korean socks) and are made of either leather or a combination of leather and fabric. It is likely that such leather socks were worn on Jeju Island to protect the feet from the cold. A condition survey of the leather socks was first conducted to establish a plan for their conservation treatment. Since the socks were in rather poor condition, it was decided to identify their original form through an investigation of relics and pertinent previous studies. The socks were cleaned in consideration of results of the condition survey, and the missing parts around the necks of the socks were reinforced in a reversible manner using counting stitches with cloth dyed to match the original color. Since the bottoms of the socks had lost much of their original form due to deterioration and disintegration in the leather, supports were made and inserted inside the socks to help retain their shape. Through these processes, the structure and characteristics of the socks and the techniques used in their production could be analyzed, their condition was stabilized, and their original form was recovered.
Research on polymer matrix composites with excellent molding processability and mechanical properties in the automotive field including hydrogen fuel cell electric vehicles is expanding to Computer-Aided Engineering (CAE) to support the design of materials with specific mechanical properties. CAE automation requires the prediction of the mechanical properties and behavior of materials. Unlike single materials, the mechanical properties prediction of polymer matrix composites is difficult to explain with formulas because the mechanical behavior is complicated to be explained only by the relationship between the matrix and the filler. In this study, the stress-strain curve according to the composition of polymer matrix composites, which was difficult to predict due to its sensitivity to large plastic deformation and composition, was predicted based on machine learning of the test data. The developed model finds a complex correlation between matrix and filler types and compositions, and predicts the total stress-strain curve meaningfully even in the absence of learned test data. It is expected that the material design AI system can be completed in the future based on the developed model that predicts the mechanical properties of polymer matrix composites even for the combination and composition that have not been learned.
The ratios of water and controlled low-strength materials (CLSM) were selected as 1:0.4, 1:0.6, 1:0.8, 1:1.0, and 1:1.2 to minimize the construction and long-term decrease in uniaxial compressive strength due to dry shrinkage through the combination of water, CLSM, and expansion agent. Approximately 2% and 5% of the expansion agent were added for each blending condition. As a result, it was found that the compressive strength decreased and the expandability increased as the specific gravity of the water increased. In addition, it was confirmed that the compressive strength increased rapidly up to 15 days of age compared to the CLSM used in the field. However, the compressive strength decreased compared to the 15 days of the age as of the 28 days of the age. It showed engineering characteristics similar to CLSM generally used in the field. Therefore, the water and the CLSM were mixed at a ratio of 1:0.8, and the field test was performed by adding 5% of an expansion agent. As a result, 28 days after age, the cavity waveform was observed using the handy GPR exploration system, and it was found that cavity waveform was relaxed or disappeared.
Monthly monitoring, 3D scan survey, and electrical resistivity survey were conducted from January 2018 to August 2022 to identify the cause of rockfall occurring in Daljeon-ri Columnar Joint (Natural Monument No. 415), Pohang. A total of 3,231 rocks fell from the columnar joint over the past 5 years, and 1,521 (47%) of the falling rocks were below 20 cm in length, 978 (30.3%) of 20-30 cm, and 732 (22.7%) of rocks over 30 cm. While the number of rockfalls by year has decreased since 2018, the frequency of rockfalls bigger than 30 cm tends to increase. Large-scale rockfalls occurred mainly during the thawing season (March-April) and the rainy season (June-July), and the analysis of the relationship between cumulative rainfall and rockfall occurrence showed that cumulative rainfall for 3 to 4 days is also closely related to the occurrence of rockfall. Smectite and illite, which are expansible clay minerals, were observed in XRD analysis of the slope material (filling minerals) in the columnar joint, and the presence of a fault fracture zone was confirmed in the electrical resistivity survey. In addition, the confirmed fault fracture zone and the maximum erosion point analyzed through 3D precision measurement coincided with the main rockfall occurrence point observed by the BTC-6PXD camera. Therefore, the main cause of rockfall at Daljeon-ri columnar joint in Pohang is a combination of internal factors (development of fault fracture zones and joints, weathering of rocks, presence of expansive clay minerals) and external factors (precipitation, rapid thawing phenomenon), resulting in large-scale rockfall. Meanwhile, it was also confirmed that the Pohang-Gyeongju earthquake, which was continuously raised, was not the main cause.
International Journal of Computer Science & Network Security
/
v.22
no.8
/
pp.153-162
/
2022
Relevance. Innovative activities in education should be aimed at ensuring the comprehensive development of the individual and professional development of students. The main idea of modular technology is that the student should learn by himself, and the teacher manages his learning activities. The advantage of modular technology is the ability of the teacher to design the study of the material in the most interesting and accessible forms for this part of the study group and at the same time achieve the best learning results. Innovative Moodle technology. it is gaining popularity every day, significantly expanding the space of teaching and learning, allowing students to study inter-faculty university programs in depth. The purpose of this study is to assess the quality of implementation of the e-learning system Moodle. The study was conducted at the South Ukrainian National Pedagogical University named after K. D. Ushinsky in order to identify barriers to the effective implementation of innovative distance learning technologies Moodle and introduce a new model that will have a positive impact on the development of e-learning. Methodology. The paper used a combination of theoretical and empirical research methods. These include: scientific analysis of sources on this issue, which allowed us to formulate the initial provisions of the study; analysis of the results of students 'educational activities; pedagogical experiment; questionnaires; monitoring of students' activities in practical classes. Results. This article evaluates the implementation of the principles of distance learning in the process of teaching and learning at the University in terms of quality. The experiment involved 1,250 students studying at the South Ukrainian National Pedagogical University named after K. D. Ushinsky. The survey helped to identify the main barriers to the effective implementation of modern distance learning technologies in the educational process of the University: the lack of readiness of teachers and parents, the lack of necessary skills in applying computer systems of online learning, the inability to interact with the teaching staff and teachers, the lack of a sufficient number of academic consultants online. In addition, internal problems are investigated: limited resources, unevenly distributed marketing advantages, inappropriate administrative structure, and lack of innovative physical capabilities. The article allows us to solve these problems by gradually implementing a distance learning model that is suitable for any university, regardless of its specialization. The Moodle-based e-learning system proposed in this paper was designed to eliminate the identified barriers. Models for implementing distance learning in the learning process were built according to the CAPDM methodology, which helps universities and other educational service providers develop and manage world-class online distance learning programs. Prospects for further research focus on evaluating students' knowledge and abilities over the next six months after the introduction of the proposed Moodle-based program.
The purpose of this study is to look at the concept of Gaebyeok as used by Kang Jeungsan (姜甑山) from a civilizational perspective. The combination of East Asian civilization during the period of Korea's port-opening and the subsequent inflow of Western powers with material civilization all at the forefront in the late Joseon Korea, served as the driving force for a new civilizational transition. Unlike the Chuk-sa Party and the Gae-hwa Party, modern Korean religions that emphasized Gaebyeok also responded to Western civilization and suggested a new view of civilization. Kang Jeung-san, resisting discrimination and oppression, presented a civilization built upon mutual beneficence while criticizing Western civilizations which centered on reason. Amid this process of the spread of modern Western civilization, Jeungsan declared the construction of a new civilization to the people who were negatively impacted by various social factions, such as class and gender discrimination, political corruption, exploitation via political corruption, and the inflow of Western powers. Jeungsanist Thought developed criticisms of materialism and human alienation, and this resulted in the claim of Gaebyeok. This was an expression of efforts to build a new civilization that aimed to harmonize, integrate, and thrive. The new civilization envisioned by Jeungsan was that of a society run according to mutual beneficence, and it can be summarized as a 'Civilization of Harmonious Union' that integrates philosophical thought and civilizational models of both East and West. This could also be referred to a 'Civilization of Public-commons and Harmony between Divine Beings and Human Beings (神人公共).' The life of Jeungsan was a life spent in the service of curing the world to save the lives of humanity. Since then, his 'movement of mutual beneficence' as observed in Mugeuk-do and Taegeuk-do were also efforts to build the new civilization envisioned by Jeungsan.
This article is a reexamination of the feminist criminal narrative I wish for what is forbidden by Yang Gui-ja in the context of the rise of the women's movement and consumer culture of the middle class in Gangnam in the 1980s and 1990s. At this time, the explosive media culture served to strengthen the ideology that placed the middle-class family at the center as well as the consumption culture. The combination of consumer media culture, women's movement and democratization created a soft and domestic male image while visualizing the material foundation of the middle class in the 1990s of South Korea. In this novel, the domestic male image transforms the feminist criminal narrative into the narrative of the femme fatale attacking the stability and dignity of the middle class family, and at the moment of the transformation, the feminist woman Kang Min-ju is killed by a lower class man who has admired and loved her. This novel is not only current but also signifying as a text that overlaps sociocultural reproduction and feminist issues of the middle class based on Gangnam in the 1990s. This is because it shows the sociocultural context of femicide, such as serial murder of targeting women, as a core code of criminal narrative to be held in Korea since the late 1990s.
Journal of the Korean Recycled Construction Resources Institute
/
v.11
no.4
/
pp.400-406
/
2023
In this study, the relationship between the material properties and air permeability characteristics was examined, an experimental method to analyze the air permeability characteristics was presented, and experimental results were derived. The effects of compressive strength and apparent density of hardened concrete on air permeability characteristics were evaluated experimentally. Focusing on the mix proportions used in nuclear power plant concrete structures, concrete test specimens were manufactured and air permeability characteristics were measured according to changes in binder, maximum aggregate size, and water-binder ratio. The apparent density was over 2,400 kg/m3 for the OPC mix and the FA-35 mix, and the air permeability for both mixes were low, in the range of 0.1-0.2 L/min. On the other hand, in the case of the combination of FA-40, FA-45, and FA-M, the apparent density was measured to be less than 2,400 kg/m3 and the air permeability was measured to be more than 0.3 L/min, experimentally verifying that the apparent density is an important factor in air permeability characteristics.
Journal of the Korean Crystal Growth and Crystal Technology
/
v.33
no.6
/
pp.234-243
/
2023
Zinc crystals of ZnO and SiO2 in glaze raw materials, developed according to composition and firing requirements, are preferred because of their high decorative properties. However, most zinc crystal glazes have a high firing temperature and a narrow firing temperature range, making it difficult to use them as commercial glazes in ceramics. Therefore, in this study, it was expected that the firing temperature of a typical zinc crystal glaze could be lowered to below 1270℃ by using the eutectic effect through mixing frit, the main raw material used in manufacturing zinc crystal glaze. As a result, not only was the formation temperature of zinc crystals lower in the mixed frit glaze, but also the firing temperature range was widened to 1230~1270℃, making it possible to develop a glaze that produces crystals stably. The firing temperature was lowered to 1230~1250℃ and the holding temperature during cooling was lowered to about 950℃, resulting in the development of an economically effective glaze. When using a combination of frit, it has been shown that the holding temperature during cooling affects the recrystallization of zinc crystals depending on the composition of the glaze, and the crystal structure can be adjusted at this time. Additionally, the amount and shape of crystals can be controlled by using a nucleating agent.
본 웹사이트에 게시된 이메일 주소가 전자우편 수집 프로그램이나
그 밖의 기술적 장치를 이용하여 무단으로 수집되는 것을 거부하며,
이를 위반시 정보통신망법에 의해 형사 처벌됨을 유념하시기 바랍니다.
[게시일 2004년 10월 1일]
이용약관
제 1 장 총칙
제 1 조 (목적)
이 이용약관은 KoreaScience 홈페이지(이하 “당 사이트”)에서 제공하는 인터넷 서비스(이하 '서비스')의 가입조건 및 이용에 관한 제반 사항과 기타 필요한 사항을 구체적으로 규정함을 목적으로 합니다.
제 2 조 (용어의 정의)
① "이용자"라 함은 당 사이트에 접속하여 이 약관에 따라 당 사이트가 제공하는 서비스를 받는 회원 및 비회원을
말합니다.
② "회원"이라 함은 서비스를 이용하기 위하여 당 사이트에 개인정보를 제공하여 아이디(ID)와 비밀번호를 부여
받은 자를 말합니다.
③ "회원 아이디(ID)"라 함은 회원의 식별 및 서비스 이용을 위하여 자신이 선정한 문자 및 숫자의 조합을
말합니다.
④ "비밀번호(패스워드)"라 함은 회원이 자신의 비밀보호를 위하여 선정한 문자 및 숫자의 조합을 말합니다.
제 3 조 (이용약관의 효력 및 변경)
① 이 약관은 당 사이트에 게시하거나 기타의 방법으로 회원에게 공지함으로써 효력이 발생합니다.
② 당 사이트는 이 약관을 개정할 경우에 적용일자 및 개정사유를 명시하여 현행 약관과 함께 당 사이트의
초기화면에 그 적용일자 7일 이전부터 적용일자 전일까지 공지합니다. 다만, 회원에게 불리하게 약관내용을
변경하는 경우에는 최소한 30일 이상의 사전 유예기간을 두고 공지합니다. 이 경우 당 사이트는 개정 전
내용과 개정 후 내용을 명확하게 비교하여 이용자가 알기 쉽도록 표시합니다.
제 4 조(약관 외 준칙)
① 이 약관은 당 사이트가 제공하는 서비스에 관한 이용안내와 함께 적용됩니다.
② 이 약관에 명시되지 아니한 사항은 관계법령의 규정이 적용됩니다.
제 2 장 이용계약의 체결
제 5 조 (이용계약의 성립 등)
① 이용계약은 이용고객이 당 사이트가 정한 약관에 「동의합니다」를 선택하고, 당 사이트가 정한
온라인신청양식을 작성하여 서비스 이용을 신청한 후, 당 사이트가 이를 승낙함으로써 성립합니다.
② 제1항의 승낙은 당 사이트가 제공하는 과학기술정보검색, 맞춤정보, 서지정보 등 다른 서비스의 이용승낙을
포함합니다.
제 6 조 (회원가입)
서비스를 이용하고자 하는 고객은 당 사이트에서 정한 회원가입양식에 개인정보를 기재하여 가입을 하여야 합니다.
제 7 조 (개인정보의 보호 및 사용)
당 사이트는 관계법령이 정하는 바에 따라 회원 등록정보를 포함한 회원의 개인정보를 보호하기 위해 노력합니다. 회원 개인정보의 보호 및 사용에 대해서는 관련법령 및 당 사이트의 개인정보 보호정책이 적용됩니다.
제 8 조 (이용 신청의 승낙과 제한)
① 당 사이트는 제6조의 규정에 의한 이용신청고객에 대하여 서비스 이용을 승낙합니다.
② 당 사이트는 아래사항에 해당하는 경우에 대해서 승낙하지 아니 합니다.
- 이용계약 신청서의 내용을 허위로 기재한 경우
- 기타 규정한 제반사항을 위반하며 신청하는 경우
제 9 조 (회원 ID 부여 및 변경 등)
① 당 사이트는 이용고객에 대하여 약관에 정하는 바에 따라 자신이 선정한 회원 ID를 부여합니다.
② 회원 ID는 원칙적으로 변경이 불가하며 부득이한 사유로 인하여 변경 하고자 하는 경우에는 해당 ID를
해지하고 재가입해야 합니다.
③ 기타 회원 개인정보 관리 및 변경 등에 관한 사항은 서비스별 안내에 정하는 바에 의합니다.
제 3 장 계약 당사자의 의무
제 10 조 (KISTI의 의무)
① 당 사이트는 이용고객이 희망한 서비스 제공 개시일에 특별한 사정이 없는 한 서비스를 이용할 수 있도록
하여야 합니다.
② 당 사이트는 개인정보 보호를 위해 보안시스템을 구축하며 개인정보 보호정책을 공시하고 준수합니다.
③ 당 사이트는 회원으로부터 제기되는 의견이나 불만이 정당하다고 객관적으로 인정될 경우에는 적절한 절차를
거쳐 즉시 처리하여야 합니다. 다만, 즉시 처리가 곤란한 경우는 회원에게 그 사유와 처리일정을 통보하여야
합니다.
제 11 조 (회원의 의무)
① 이용자는 회원가입 신청 또는 회원정보 변경 시 실명으로 모든 사항을 사실에 근거하여 작성하여야 하며,
허위 또는 타인의 정보를 등록할 경우 일체의 권리를 주장할 수 없습니다.
② 당 사이트가 관계법령 및 개인정보 보호정책에 의거하여 그 책임을 지는 경우를 제외하고 회원에게 부여된
ID의 비밀번호 관리소홀, 부정사용에 의하여 발생하는 모든 결과에 대한 책임은 회원에게 있습니다.
③ 회원은 당 사이트 및 제 3자의 지적 재산권을 침해해서는 안 됩니다.
제 4 장 서비스의 이용
제 12 조 (서비스 이용 시간)
① 서비스 이용은 당 사이트의 업무상 또는 기술상 특별한 지장이 없는 한 연중무휴, 1일 24시간 운영을
원칙으로 합니다. 단, 당 사이트는 시스템 정기점검, 증설 및 교체를 위해 당 사이트가 정한 날이나 시간에
서비스를 일시 중단할 수 있으며, 예정되어 있는 작업으로 인한 서비스 일시중단은 당 사이트 홈페이지를
통해 사전에 공지합니다.
② 당 사이트는 서비스를 특정범위로 분할하여 각 범위별로 이용가능시간을 별도로 지정할 수 있습니다. 다만
이 경우 그 내용을 공지합니다.
제 13 조 (홈페이지 저작권)
① NDSL에서 제공하는 모든 저작물의 저작권은 원저작자에게 있으며, KISTI는 복제/배포/전송권을 확보하고
있습니다.
② NDSL에서 제공하는 콘텐츠를 상업적 및 기타 영리목적으로 복제/배포/전송할 경우 사전에 KISTI의 허락을
받아야 합니다.
③ NDSL에서 제공하는 콘텐츠를 보도, 비평, 교육, 연구 등을 위하여 정당한 범위 안에서 공정한 관행에
합치되게 인용할 수 있습니다.
④ NDSL에서 제공하는 콘텐츠를 무단 복제, 전송, 배포 기타 저작권법에 위반되는 방법으로 이용할 경우
저작권법 제136조에 따라 5년 이하의 징역 또는 5천만 원 이하의 벌금에 처해질 수 있습니다.
제 14 조 (유료서비스)
① 당 사이트 및 협력기관이 정한 유료서비스(원문복사 등)는 별도로 정해진 바에 따르며, 변경사항은 시행 전에
당 사이트 홈페이지를 통하여 회원에게 공지합니다.
② 유료서비스를 이용하려는 회원은 정해진 요금체계에 따라 요금을 납부해야 합니다.
제 5 장 계약 해지 및 이용 제한
제 15 조 (계약 해지)
회원이 이용계약을 해지하고자 하는 때에는 [가입해지] 메뉴를 이용해 직접 해지해야 합니다.
제 16 조 (서비스 이용제한)
① 당 사이트는 회원이 서비스 이용내용에 있어서 본 약관 제 11조 내용을 위반하거나, 다음 각 호에 해당하는
경우 서비스 이용을 제한할 수 있습니다.
- 2년 이상 서비스를 이용한 적이 없는 경우
- 기타 정상적인 서비스 운영에 방해가 될 경우
② 상기 이용제한 규정에 따라 서비스를 이용하는 회원에게 서비스 이용에 대하여 별도 공지 없이 서비스 이용의
일시정지, 이용계약 해지 할 수 있습니다.
제 17 조 (전자우편주소 수집 금지)
회원은 전자우편주소 추출기 등을 이용하여 전자우편주소를 수집 또는 제3자에게 제공할 수 없습니다.
제 6 장 손해배상 및 기타사항
제 18 조 (손해배상)
당 사이트는 무료로 제공되는 서비스와 관련하여 회원에게 어떠한 손해가 발생하더라도 당 사이트가 고의 또는 과실로 인한 손해발생을 제외하고는 이에 대하여 책임을 부담하지 아니합니다.
제 19 조 (관할 법원)
서비스 이용으로 발생한 분쟁에 대해 소송이 제기되는 경우 민사 소송법상의 관할 법원에 제기합니다.
[부 칙]
1. (시행일) 이 약관은 2016년 9월 5일부터 적용되며, 종전 약관은 본 약관으로 대체되며, 개정된 약관의 적용일 이전 가입자도 개정된 약관의 적용을 받습니다.