• Title/Summary/Keyword: boundary-making

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Study on derivation from large-amplitude size dependent internal resonances of homogeneous and FG rod-types

  • Somaye Jamali Shakhlavi;Reza Nazemnezhad
    • Advances in nano research
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    • v.16 no.2
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    • pp.111-125
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    • 2024
  • Recently, a lot of research has been done on the analysis of axial vibrations of homogeneous and FG nanotubes (nanorods) with various aspects of vibrations that have been fully mentioned in history. However, there is a lack of investigation of the dynamic internal resonances of FG nanotubes (nanorods) between them. This is one of the essential or substantial characteristics of nonlinear vibration systems that have many applications in various fields of engineering (making actuators, sensors, etc.) and medicine (improving the course of diseases such as cancers, etc.). For this reason, in this study, for the first time, the dynamic internal resonances of FG nanorods in the simultaneous presence of large-amplitude size dependent behaviour, inertial and shear effects are investigated for general state in detail. Such theoretical patterns permit as to carry out various numerical experiments, which is the key point in the expansion of advanced nano-devices in different sciences. This research presents an AFG novel nano resonator model based on the axial vibration of the elastic nanorod system in terms of derivation from large-amplitude size dependent internal modals interactions. The Hamilton's Principle is applied to achieve the basic equations in movement and boundary conditions, and a harmonic deferential quadrature method, and a multiple scale solution technique are employed to determine a semi-analytical solution. The interest of the current solution is seen in its specific procedure that useful for deriving general relationships of internal resonances of FG nanorods. The numerical results predicted by the presented formulation are compared with results already published in the literature to indicate the precision and efficiency of the used theory and method. The influences of gradient index, aspect ratio of FG nanorod, mode number, nonlinear effects, and nonlocal effects variations on the mechanical behavior of FG nanorods are examined and discussed in detail. Also, the inertial and shear traces on the formations of internal resonances of FG nanorods are studied, simultaneously. The obtained valid results of this research can be useful and practical as input data of experimental works and construction of devices related to axial vibrations of FG nanorods.

The concept & applying of cognitive warfare, phychological warfare and information warfare (인지전, 심리전, 정보전의 개념과 적용)

  • Chang In Lee
    • The Journal of the Convergence on Culture Technology
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    • v.10 no.6
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    • pp.437-441
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    • 2024
  • This study summarizes the confusingly used concepts of cognitive warfare, psychological warfare, and information warfare, and studies how to apply them to warfare. Cognitive warfare, psychological warfare, and information warfare are aspects of war that use human mental processes, psychology, and information as targets or means of operation, respectively, and it is difficult to divide the boundary between military and non-military warfare because mental processes, psychology, and information are connected to the human five senses, and influencing the human five senses is not limited to the military field. Cognitive warfare, psychological warfare, and information warfare are not easy to distinguish because they have the common goal of influencing human decision-making, and in recent years, they have used text, pictures, and videos via the Internet as their main means. Through this study, you will learn how to distinguish between cognitive, psychological, and information warfare and how they are applied in warfare.

Dimensional Quality Assessment of Steel H-Beams Using Terrestrial Laser Scan Data

  • Mathanraj Rajendran;Sung-Han Sim;Min-Koo Kim;Yoon-Ki Choi
    • International conference on construction engineering and project management
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    • 2024.07a
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    • pp.264-270
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    • 2024
  • In the construction industry, steel structures are prominent due to their exceptional strength and high bearing capacity, making them resilient against natural calamities. However, the stability and overall structural integrity of these steel structures depend significantly on the precision of the individual steel members used. Presently, the dimensions of these steel members are typically measured manually using mechanical instruments such as steel tape and vernier calipers. This conventional approach is not only time-consuming but also highly vulnerable to human error. Consequently, there is a growing need for more accurate and reliable methods for assessing the dimensions of steel members. This paper aims to measure the dimensions of key checklists of the cross-section surface of the steel H-beams using Terrestrial Laser Scan (TLS) data. This study involves the automatic extraction of scan points associated with the cross-section surface of the H-beam members using RANSAC. By the end, an algorithm was developed to predict the actual edge points belonging to the boundary of the extracted surface and introduced an edge loss compensation model to compensate the losses occurred due to uncertainties. Experimental evaluations were conducted using various scan data collected from steel H-beam and the measured dimensions were subsequently compared with manual measurements and dimensions obtained through the previously proposed method, demonstrating that the measurements meet 1mm accuracy and are within the allowable tolerance range followed in industry. This research underscores the efficiency and reliability of the introduced approach, offering a promising solution to enhance the dimensional quality assessment of steel H-beams in the construction industry.

60 Years since the Armistice Treaty, the NLL and the North-Western Islands (정전협정 60년, NLL과 서북 도서)

  • Jhe, Seong-Ho
    • Strategy21
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    • s.31
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    • pp.27-56
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    • 2013
  • The United Nations Command (UNC) and the communist North failed to reach an agreement on where the maritime demarcation line should be drawn in the process of signing a truce after the Korean War because of the starkly different positions on the boundary of their territorial waters. As a result, the Armistice Treaty was signed on July 1953 without clarification about the maritime border. In the following month, Commander of the UNC unilaterally declared the Northern Limit Line (NLL) as a complementing measure to the Armistice. Referring to this, North Korea and its followers in South Korea wrongfully argue that the NLL is a "ghost line" that was established not based on the international law. However, one should note that the waters south of the NLL has always been under South Korea's jurisdiction since Korea's independence from Japan on August 15, 1945. There is no need to ask North Korea's approval for declaring the territorial waters that had already been under our sovereign jurisdiction. We do not need North Korea's approval just as we do not need Japan's approval with regard to our sovereign right over Dokdo. The legal status of the NLL may be explained with the following three characteristics. First, the NLL is a de facto maritime borderline that defines the territorial waters under the respective jurisdiction of the two divided countries. Second, the NLL in the West Sea also serves as a de facto military demarcation line at sea that can be likened to the border on the ground. Third, as a contacting line where the sea areas controlled by the two Koreas meet, the NLL is a maritime non-aggression line that was established on the legal basis of the 'acquiescence' element stipulated by the Inter-Korea Basic Agreement (article 11) and the Supplement on the Non-aggression principle (article 10). Particularly from the perspective of the domestic law, the NLL should be understood as a boundary defining areas controlled by temporarily divided states (not two different states) because the problem exists between a legitimate central government (South Korea) and an anti-government group (North Korea). In this sense, the NLL problem should be viewed not in terms of territorial preservation or expansion. Rather, it should be understood as a matter of national identity related to territorial sovereignty and national pride. North Korea's continuous efforts to problematize the NLL may be part of its strategy to nullify the Armistice Treaty. In other words, North Korea tries to take away the basis of the NLL by abrogating the Armistice Treaty and creating a condition in which the United Nations Command can be dissolved. By doing so, North Korea may be able to start the process for the peace treaty with the United States and reestablish a maritime line of its interest. So, North Korea's rationale behind making the NLL a disputed line is to deny the effectiveness of the NLL and ask for the establishment of a new legal boundary. Such an effort should be understood as part of a strategy to make the NLL question a political and military dispute (the similar motivation can be found in Japan's effort to make Dokdo a disputed Island). Therefore, the South Korean government should not accommodate such hidden intentions and strategy of North Korea. The NLL has been the de facto maritime border (that defines our territorial waters) and military demarcation line at sea that we have defended with a lot of sacrifice for the last sixty years. This is the line that our government and the military must defend in the future as we have done so far. Our commitment to the defense of the NLL is not only a matter of national policy protecting territorial sovereignty and jurisdiction; it is also our responsibility for those who were fallen while defending the North-Western Islands and the NLL.

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Application of the LISFLOOD-FP model for flood stage prediction on the lower mankyung river (만경강 하류 홍수위 예측을 위한 LISFLOOD-FP 모형의 적용성 검토)

  • Jeon, Ho-Seong;Kim, Ji-sung;Kim, Kyu-ho;Hong, il
    • Journal of Korea Water Resources Association
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    • v.49 no.6
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    • pp.459-467
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    • 2016
  • LISFLOOD-FP model in which channel flows are resolved separately from the floodplain flows using either a kinematic or diffusive wave approximation has been used to analyze flooding behavior on the lower Mankyung River influenced by backwater. A calibration and validation process was applied using the previous flood events to assess the model performance. Sensitivity analysis was conducted for main calibrated parameters, such as Manning roughness coefficient and downstream boundary condition. Also, we examined the effect of warm-up for the initial conditions. The results show that the computed hydrograph is in good agreement with measured data on the study reach, even though it was a hydrologic kinematic wave model. The sensitive analysis show that the difference between the computed results may be greater depending on the used calibrated parameters and that the sufficient calibration/validation process against various flood events is necessary. If the flood inundation simulation is performed using the validated model, it is expected to be able to contribute about river planning and policy decision-making for flood damage reduction.

On the Determination of Slope Stability to Landslide by Quantification(II) (수량화(數量化)(II)에 의한 산사태사면(山沙汰斜面)의 위험도(危險度) 판별(判別))

  • Kang, Wee Pyeong;Murai, Hiroshi;Omura, Hiroshi;Ma, Ho Seop
    • Journal of Korean Society of Forest Science
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    • v.75 no.1
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    • pp.32-37
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    • 1986
  • In order to get the fundamental information that could be useful to judge the potentiality of occurrence of rapid shallow landslide in the objective slope, factors selected on Jinhae regions in Korea, where many landslides were caused by heavy rainfall of daily 465 mm and hourly 52mm in August 1979, was carried out through the multiple statistics of quantification method (II) by the electronic computer. The net system with $2{\times}2cm$ unit mesh was overlayed with the contour map of scale 1:5000. 74 meshes of landslides and 119 meshes of non-landslide were sampled out to survey the state of vegetative cover and geomorphological conditions, those were divided into 6 items arid 27 categories. As a result, main factors that would lead to landslide were shown in order of vegetation, slope type, slope position, slope, aspect and numbers of stream. Particularly, coniferous forest of 10 years old, concave slope and foot of mountain were main factors making slope instability. On the contrary, coniferous forest of 20-30 years old, deciduous forest, convex slope and summit contributed to the stable against Landslide. The boundary value between two groups of existence and none of landslides was -0.123, and its prediction was 72%. It was well predicted to divide into two groups of them.

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Resistive Switching Characteristic of Direct-patternable Amorphous TiOx Film by Photochemical Metal-organic Deposition (광화학증착법에 의한 직접패턴 비정질 TiOx 박막의 제조 및 저항변화 특성)

  • Hwang, Yun-Kyeong;Lee, Woo-Young;Lee, Se-Jin;Lee, Hong-Sub
    • Journal of the Microelectronics and Packaging Society
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    • v.27 no.1
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    • pp.25-29
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    • 2020
  • This study demonstrates direct-patternable amorphous TiOx resistive switching (RS) device and the fabrication method using photochemical metal-organic deposition (PMOD). For making photosensitive stock solutions, Ti(IV) 2-ethylhexanoate was used as starting precursor. Photochemical reaction by UV exposure was observed and analyzed by Fourier transform infrared spectroscopy and the reaction was completed within 10 minutes. Uniformly formed 20 nm thick amorphous TiOx film was confirmed by atomic force microscopy. Amorphous TiOx RS device, formed as 6 × 6 ㎛ square on 4 ㎛ width electrode, showed forming-less RS behavior in ±4 V and on/off ratio ≈ 20 at 0.1 V. This result shows PMOD process could be applied for low temperature processed ReRAM device and/or low cost, flexible memory device.

Development of BIM Templates for Vest-Pocket Park Landscape Design (소공원의 조경설계를 위한 BIM 템플릿 개발)

  • Seo, Young-hoon;Kim, Dong-pil;Moon, Ho-Gyeong
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.1
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    • pp.40-50
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    • 2016
  • A BIM, which is being applied actively to the construction and civil construction industries, is a technology that can maximize efficiency of various sectors from initial planning and design, construction, and maintenance, to demolition; however, it is in the introductory phase in the field of domestic landscaping. In order to introduce and promote BIM in the field of landscape design, this study developed a prototype of a library and template and analyzed the performance of trial application. For the development of a prototype, annotations and types were analyzed from floor plans of existing small parks, and components of landscape template were deduced. Based on this, play facilities, pergola, and benches were madeintofamily and templates, making automatic design possible. In addition, annotations and tags that are often used in landscape design were made, and a 3D view was materialized through visibility/graphic reassignment. As for tables and quantities, boundary stone table, mounding table, summary sheet of quantities, table of contents, and summary sheet of packaging quantities were grouped and connected with floor plans; regarding landscaping trees, classification criteria and name of trees that are suitable for domestic situations were applied. A landscape template was created to enable the library file format(rfa) that can be mounted on a building with BIM programs. As for problems that arose after the trial application of the prepared template, some CAD files could not be imported; also, while writing tables, the basis of calculation could not be made automatically. Regarding this, it is thought that functions of a BIM program and template need improvement.

Assessment of the Potential Carbon Credits from Reducing Emissions from Deforestation and Enhancement of Forest Carbon Stock Activities in Developing Countries (개도국의 산림전용으로 인한 온실가스 배출량 감축 및 산림탄소축적 증진 활동의 탄소배출권 잠재력 평가)

  • Bae, Jae Soo;Bae, Ki Kang
    • Journal of Korean Society of Forest Science
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    • v.98 no.3
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    • pp.263-271
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    • 2009
  • This study aims to identify negotiation alternatives related to Post-2012 reducing emissions from deforestation (RED) and enhancement of forest carbon stock (EFCS) activities. It also aims to recommend a negotiation strategy considering environmental integrity and national interest on the basis of estimating reduction potentials of each alternative on the assumption that tradable carbon credits play an important role as positive incentives. In order to estimate greenhouse gas (GHG) reduction potentials and income potential from RED and EFCS activities, 99 countries were selected by the Global Forest Resources Assessment of the Food and Agriculture Organization of the United Nations. A 'baseline and credit' method was applied to estimate RED activities. Gross-net and net-net methods were applied for EFCS activities. According to the results, Brazil, Indonesia, and the Democratic Republic of Congo have more potential to get positive incentives through RED, while China, Chile, and the Republic of Korea have more potential to get positive incentives through EFCS. This study suggests including both RED and EFCS activities in the boundary of policy approaches and endowment of positive incentives to consider GHG reduction potentials in the global scale and equity among developing countries. Making a discount rate application of forest management activities can be also recommended to factor out the effects of human-induced activities by EFCS activities.

Development of Work Stress Measurement Tool for Academic Librarians (대학도서관 사서의 직무스트레스 측정 도구 개발)

  • Lee, Jong Yoon;Cho, Hyun Yang
    • Journal of the Korean Society for Library and Information Science
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    • v.47 no.3
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    • pp.181-205
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    • 2013
  • The purpose of this study is to develop a job-stress scale for librarians who work in university libraries. The study was first conducted by analyzing existing representative job-stress scales that are used domestically and internationally. To understand the characteristic of particular job stress that academic librarians have, the in-depth interview among qualitative research methods was selected, and 15 librarians who work at a 4-year system university libraries participated in this study. Based on the results of the questionnaire survey, the reliability and validity were verified. To analyze the validity, exploratory factor analysis was carried out. To extract factors, principal component analysis was used. To extract factors, principal component analysis was used. For the rotation method, a varimax rotation was applied. A tertiary measurement tool with a total of 46 questions for 11 factors was developed after removing measurement questions that were rejected as a result of the analysis. As a result of factor analysis on the tertiary measurement tool, 11 factors were extracted. Those 11 factors include 'peer relation conflict factor(factor 1)', 'superior-subordinate relation conflict factor (factor 2)', 'work compensation evaluation factor(factor 3)', 'emotional labor factor(factor 4)', 'physical environmental factor(factor 5)', 'employment stability(factor 6)', 'job demand factor(psychological) (factor 7)', 'decision-making and responsibility factor(factor 8)', 'work complexity factor(factor 9)', 'work boundary conflict factor(factor 10)', and 'job demand factor(physical)(factor 11)'.