• Proceedings of the Acoustical Society of Korea Conference
• /
• spring
• /
• pp.409-416
• /
• 1999

액체/고체 경계면에 레일레이각으로 초음파 pulse를 입사시키면 입사된 에너지의 상당 부분이 고체쪽으로 침투여 표면으로부터 약 1.5 파장 깊이 정도까지 에너지 분포를 가지고 고체 표면을 따라 전파하는 레일레 이파로 전환되며, 이러한 입사각에서는 기하학적인 거울 반사가 일어나지 않고 반사파의 중심이 Schoch 변위만큼 전방으로 이동되고, 또 입사 방향으로 후반 산란되는 초음파의 신호가 급격히 증가하는 현상이 관찰된다. 만일 고체에서 초음파의 감쇠가 산란에 의해 크게 영향을 받고, 레일레이각에서 고체 쪽으로 침투한 에너지의크기를 $E_0$라고 하면, 고체 표면과 표면 근처를 전파하는 레일레이파의 산란파 에너지, $E_S$는 Schoch 변위, ${\Delta}_S$와 산란에 의한 감쇠계수 ${\alpha}_S$에 비례하는 관계가 있음을 이론적으로 구하였다. 입사 방향으로 후방산란되는 초음파는 산란파의 일부이므로 후방산란 초음파 에너지, E_{Bs}도 이와 같은 관계를 가진다. 그러므로, 레일레이각으로 입사된 초음파의 후방산란 에너지, $E_{B_S}$ 산란체(e.g. grain)의 평균 크기, D와 주파수 f와는 레일레이 산란 영역과 Stochastic 산란 영역에 대해 각각 $E_{B_S}\;\propto\;D^{3}f^{3}$와 $E_{B_S}\;\propto\;D\;f$인 관계를 가지는 것으로 얻어졌다. 이것은 액체/고체 경계면에서 레일레이각으로 입사되어 레일레이파로 전환된 초음파가 다시 액체로 그 에너지를 누설하여 그 산란 영역이 Schoch 변위 내에서 일어나기 때문이며, 이러한 영향에 의해서일반적인 산란에서의 주파수 의존성과는 달리 각 산란 영역에서 그 지수는 1씩 작은 값을 갖는다.향에 따라 음장변화가 크게 다를 것이 예상되므로 이를 규명하기 위해서는 궁극적으로 3차원적인 음장분포 연구가 필요하다. 음향센서를 해저면에 매설할 경우 수충의 수온변화와 센서 주변의 수온변화 사이에는 어느 정도의 시간지연이 존재하게 되므로 이에 대한 영향을 규명하는 것도 센서의 성능예측을 위해서 필요하리라 사료된다.가지는 심부 가스의 개발 성공률을 증가시키기 위하여 심부 가스가 존재하는 지역의 지질학적 부존 환경 및 조성상의 특성과 생산시 소요되는 생산비용을 심도에 따라 분석하고 생산에 수반되는 기술적 문제점들을 정리하였으며 마지막으로 향후 요구되는 연구 분야들을 제시하였다. 또한 참고로 현재 심부 가스의 경우 미국이 연구 개발 측면에서 가장 활발한 활동을 전개하고 있으며 그 결과 다수의 신뢰성 있는 자료들을 확보하고 있으므로 본 논문은 USGS와 Gas Research Institute(GRI)에서 제시한 자료에 근거하였다.ऀĀ耀Ā삱?⨀؀Ā Ā?⨀ጀĀ耀Ā?돀ꢘ?⨀硩?⨀ႎ?⨀?⨀넆돐쁖잖⨀쁖잖⨀／ࠐ?⨀焆덐瀆倆Āⶇ퍟ⶇ퍟ĀĀĀĀ磀鲕좗?⨀肤?⨀⁅Ⴅ?⨀쀃잖⨀䣙熸ጁ↏?⨀

• Journal of the Earthquake Engineering Society of Korea
• /
• v.11 no.2 s.54
• /
• pp.81-94
• /
• 2007

In most experimental researches on the liquefaction phenomenon, an earthquake as a random vibration has been regraded as a sinusoidal wave or a triangular wave with an equivalent amplitude. Together with the development in the part of signal control and data acquisition, dynamic experimental equipments in the soil dynamics have also developed rapidly and further more, several real earthquakes have been simulated in the large model test such as shaking table tests and centrifuge tests. In Korea, several elementary laboratory tests to simulate the real earthquake load were performed. From these test results, it was reported that the sinusoidal wave cannot reliably reflect the soil dynamic behavior under the real earthquake motion. In this study, 4 types of dynamic motions such as the sinusoidal wave, the triangular wave, the incremental triangular wave and several real earthquake motions which were classified with shock-type and vibration-type were loaded to find something new to explain the change of the excess pore water pressure under the real earthquake load. Through the detailed investigation and comparison on all test results, it is found that the dynamic flow is generated by the soil plastic deformation and the velocity head of dynamic flow is changed the pressure head in the un-drained condition. It can be concluded that the change of the excess pore water pressure is related to the pressure head of dynamic flow. Lastly, a new hypothesis to explain such a liquefaction initiation phenomenon under the real earthquake load is also proposed and verified.

• Communications of Mathematical Education
• /
• v.20 no.3 s.27
• /
• pp.407-423
• /
• 2006

The reason why creativity becomes the important subject in 21th century is that it does an important role which solves many problems surrounding our whole life in this internationalization, globalization, knowledge-information age. But scholars who formerly researched the creativity-field explain the necessity of creativity with the internal and fundamental reasons. That is, scholars say that creative activities produce originative products and originality itself. And it is the root of which will be able to discover meaning of life and it -creativity - is successive activities that is demanded when individual life want to obtain important value by expressing one's inner world to the outside using creative resource. Recently, with the trends of present age and the educational needs, research about creativity is actively carried out and it draws out the results that creativity can be developed and enhanced through education and training. So, now many researches have focused on how to develop the creativity. Investigating those researches, we found that the recent issues of researches on creativity were changing and now they focused on creative instruction methods and behavioral factors. Especially, they were selected as the subject related to the creative education - creative instructional method and program, atmosphere in classroom, and factors of teacher. It means that the past researches which were a little bit conceptive have been changing to material ones which will be able to enhance creativity and its effect. So, in this research, we have developed the program for CPS(Creativity Problem Solving) and verified its effect.

• Journal of the Korea Institute of Building Construction
• /
• v.13 no.2
• /
• pp.181-192
• /
• 2013

Given both structural safety and economic benefits of aging facilities, remodelling of the existing facilities is preferable to reconstruction. This recognition provides an opportunity to reduce the commitment of resources and national budget. However, when a subordinate troop asks for remodeling or reconstruction of a deteriorated facility, it is difficult to ensure the consistency and objectivity in the process of decision making for the alternatives due to the absence of systematic and quantitative rating methodology. Their economic evaluation methodology only exists in a manual format. Thus, further research is required for converting the methodology into an automated system in view of practicality such as rapid and accurate data processing. The contributions of this study are as follows: 1) Literature review found out a representative economic evaluation model focused on military facilities, and comparative analysis with a similar study identified the strength and weakness. 2) this study presented how to convert the theoretical framework which enables to solve a specific subject matter into an automated system. 3) it developed a user friendly interfaces which consist of four functional modules by considering the usability and accessibility of the system user. 4) the developed system was verified by a case study in terms of four kinds of performance indicators.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.32 no.6
• /
• pp.890-901
• /
• 2008

This study explores an initial framework for online product categorization by examining the relationships among Internet motivations, buying tendencies, and online purchase intentions for product categories. A total of 217 usable questionnaires were obtained from respondents in a southwestern state in the United States. A path model using a correlation matrix with maximum likelihood was estimated using LISREL 8.53. Findings indicated that Internet motivations consisted of four factors: Diversion, Economic, Information, and Social motivations. In addition, online products were classified into three categories based on purchase intentions: Sensory, Cognitive, and Search products. Estimated path model showed that diversion and economic motivations affected impulse buying tendency, whereas economic, information and social motivations influenced planned buying tendency in the online context. Also, the buying tendencies were significantly related to online purchase intentions for the product categories. Purchase intentions for sensory products were more strongly affected by impulse buying tendency, whereas purchase intentions for cognitive and search products were more strongly affected by planned buying tendency. Theoretical and managerial implications were discussed for devising an appropriate e-market strategy for specific product categories.

• Journal of Science and Technology Studies
• /
• v.19 no.3
• /
• pp.167-200
• /
• 2019

In recent years, the material has mattered to the humanities and social sciences in the West and feminism is no exception. It is a notable change that feminist analyses, which had previously shown critiques against science and technology, attempted to build new engagements with matter. STS (science and technology studies) has also accumulated scholarships and developed conceptual tools on the thing or the existence itself through "the ontological turn." The objective of this paper is not to introduce new materialism or new material feminism in full, but to reveal the possibility and potential of doing science, technology and women studies by selectively relying on the achievement of new materialism feminism. This article shows a way to study women's practice of science and technology by analyzing the case of plastic surgery practices through the ontological concepts of STS, particularly those of Annemarie Mol, Karen Barad, and Charis Thompson, and proposes a new engagement among new materialism, feminism, and STS. This article is organized as follows. First of all, after briefly discussing main issues in new material feminism, I will show the limitations of previous feminist studies of plastic surgery under the light of new material feminism. The rest of the article introduces the conceptual tools of ontological STS, describes plastic surgery practices with those tools, and finally provides their feminist implications.

• The Korean Journal of Archival Studies
• /
• no.74
• /
• pp.5-43
• /
• 2022

This study aims to explore the 'affective value' of records. Traditionally, records have been evaluated as having evidence value, information value, and artificial value. However, the 'affective turn' in the humanities and social sciences, which began in the 1990s, calls for discussion on the affective value of records. The overseas archive academia is in full swing discussing the emotional value of records after the 'affective turn'. However, there is no emotional discussion on records in the domestic archive academia. This study first conducts theoretical discussions to overcome these domestic limitations and explore the emotional value of archives in earnest. Following the theoretical discussion, a specific case will be dealt with next. As a representative storage of affect, which records the pain, sadness, and condolences of the domestic disaster era, this study investigates the record management case of the 4.16 Memory Storage. The Ferry Sewol disaster, which provided a dramatic opportunity to witness the unexpected ripple effect of affect in Korea, and the 4.16 Memory Storage as a recording activity, can be seen as a representative example of affective recording of the pain and sadness of survivors of the trauma incident. It will capture the differentiation of affet recording, which is different from the record management practice, and demonstrate empirically how this differentiation is implemented from collection to evaluation and service through the '4.16 Memory Storage'.

• Journal of the Korea Society of Computer and Information
• /
• v.14 no.11
• /
• pp.81-90
• /
• 2009

It is inevitable for college students to be confused when they first face university education, which requires them to be self-reliant and responsible, after finishing their course of education, which is passive under control of period and environment, in primary, middle, and high schools. Introduction to college courses, which require students to be subjective and responsible, to be taken after chronically and environmentally controlled primary and secondary education, are but confusing. In this stage, college education should provide ground for educational system so that students can escape from repetitively enforced way of studying of fixed curriculums and study creatively and subjectively while befitting each individual's aptitude. For instance, in programming classes in engineering school, students scholastic achievements are closely interrelated with the professor's educational principles. A change in method of education, from one previously focused on theoretical contents to one centered on practices and experiments, can reap good results. Also, as the need arose for introduction of practice-focused evaluation system, from recognition-centered professor evaluating system to enablement of actively developing creative and self-reliant way of learning, we applied the Rublic System. It is a feedback system that all or most students become the evaluators, of which the indicators of evaluation such as category, standard, and score are public. We have looked into whether or not there has been an improvement in GPAs of students, and if there exists an improvement then what efforts should be made to solidify the system.

• The Journal of the Convergence on Culture Technology
• /
• v.9 no.2
• /
• pp.159-169
• /
• 2023

The purpose of this study is, first, to establish a theory about the conflict between sustainable tourism development and the restoration process of modern cultural heritage. Second, a research model is established through literature research, and the difference in perception between the local government (Incheon Jung-gu Office) and the local residents is analyzed. Third, based on the results of the analysis, we will present a conflict management strategy for sustainable tourism development in the modern hotel restoration project. If a conflict management strategy is presented based on the analysis results, first, a procedure to confirm whether the goal of development for sustainable tourism development and local residents is the same before the modern cultural heritage restoration project is necessary. Second, it is necessary to coordinate opinions on priority items among sustainable tourism development indicators during the modern cultural heritage restoration project. Third, in the modern cultural heritage restoration project, priority should be given to the change of awareness of the development subject rather than the change of awareness of the local residents. Fourth, in the modern cultural heritage restoration project, the development entity should attempt continuous dialogue and compromise in an effort to find an alternative that satisfies local residents. Fifth, in the modern cultural heritage restoration project, it would be effective to pay special attention to and focus on the part of 'adjustment of opinions' where the difference of opinion between the developer and the local residents is the largest.

• The Korean Journal of Woman Psychology
• /
• v.17 no.4
• /
• pp.679-704
• /
• 2012

The purpose of this study was to have a phenomenological understanding of the experiences in the marital relationship after the first baby is born. For this purpose, thirteen couples (marriage duration of less than five years; within three years of the child birth) were recruited and semi-structured interviews were conducted. The interview data were analyzed through the open coding, axial coding, and selective coding. In the next step, we derived the marital relationship paradigm after the first baby arrived. The causal/situational conditions that caused changes in the marital relationship were the parenting burden and the marital adjustment level. The central phenomena were parenting and housework burden, which were moderated by the husbands' support. The action/interaction strategies were couple's high awareness and acceptance for their new role and pursuit of the shared meaning of the family. When the strategies were successful, a deeply satisfying feeling and shared values could be obtained. Finally, we identified the core category to integrate of other categories into a conceptual framework, and that is 'the awareness and acceptance for their new role and the pursuit of a sense of We-ness'.