Earticle

The purpose of this study is to investigate how individual students' heuristics and control actions contribute to the formation of group-level control during collaborative mathematical problem solving. To achieve this, the researcher observed two ninth-grade students solving an unstructured quadratic function task involving a drone’s trajectory using a "think-aloud" method. The analysis, based on Schoenfeld’s framework, revealed that while individual students actively utilized metacognitive control—such as questioning the use of conditions and setting strategic goals—these actions were not stably organized into effective group-level control, often leading to repetitive interruptions or regressive discussions. The findings provide two key pedagogical implications: (a) effective group-level control requires a pre-established collective consensus on fundamental problem premises, such as coordinate settings and variable interpretations; (b) individual self-questioning does not automatically scale to group-level control without specific social interaction mechanisms to bridge the two. Finally, this study suggests further research to explore the specific instructional conditions and discourse structures that facilitate the transition of individual metacognitive questions into stable group-level control actions.

차세대 3차원 건축설계 기법으로 각광받고 있는 BIM(Building Information Modeling)기술을 기반으로 하는 건축 설계 프로그램 중 대표적인 프로그램으로 Revit 프로그램이 있다. Revit은 정보 입력 측면을 강화시켜 설계 단계에서부터 구성요소의 정보 패밀리라는 오브젝트로 만들어 알기 쉽게 구성 요소를 파악 할 수 있는 프로그램이나, 이 프로그램에서 추출된 도면 출력파일들을 쉽게 비교하는 프로그램이 전무하고, 이로 인하여 협업 시에 수정된 동일 도면들에 대한 변경 내용의 분석이나 도면 정보의 손쉬운 공유가 어려운 점이 문제로 대두되고 있다. 이에 본 논문에서는 Revit을 통한 출력 도면 파일들의 병렬적 협력 작업이 효율적으로 이루어지도록 하기 위하여 동일 도면에 출력 파일들에 대한 버전 관리 시스템의 제안 및 구현을 하였으며 다른 버전 도면 파일들 간의 수정 부분을 검출하기 위한 개선된 KMP알고리듬을 제안한다.

Revit program is one of the architectural design programs based on the BIM (Building Information Modeling) technology, which is attracting attention as a next-generation three-dimensional architectural design technique. Revit is a program that enhances the information input side and makes it easy to understand components by making it an object called an information family of components from the design stage, but there is no program that easily compares the drawing output files extracted from this program. It is difficult to analyze the changes to the same drawings modified at the time of collaboration and easily share the drawing information. In this paper, we propose and implement a version management system for the output files on the same drawing, so that the parallel collaboration work of output drawing files through Revit can be efficiently performed. We propose an improved KMP algorithm.

This paper proposes a fixed-time event-triggered anti-windup collaborative controller for a towing system consisting of an unactuated offshore platform and multiple tugs. Firstly, a fixed-time virtual controller is proposed to acquire required towing force for the platform to track expected trajectory. Subsequently, the required towing force is allocated as desired towline tensions by quadratic programming algorithm, and corresponding desired length of each towline is calculated through towline catenary model. Based on desired towline tensions and lengths, a fixed-time collaborative controller is constructed for tugs with following key components: the input saturation of tugs is approximated by a Gaussian error function; a fixed-time extended state observer is employed to rapidly estimate compound disturbances including saturation approximation errors; a novel dynamic threshold event-triggered mechanism is designed to decrease the control input update frequency while maintaining the convergence performance of entire control system. Finally, simulation results demonstrate the effectiveness of proposed control method.

Impact of business process re-engineering requires the fundamental rethinking of how information systems are analyzed and designed. It is no longer sufficient to establish a monolithic system for fixed business environments. Information systems must be adaptive in nature. This demand is also applied in production domain. Enabling concept for the adaptive information system is reusability. This paper presents a new object-oriented analysis process for creating such reusable software components in production domain, especially for production planning and scheduling. Our process called MeCOMA is based on three meta-models: physical object meta-model, data object meta-model, and activity object meta-model. After the three meta-models are extended independently for a given production system, they are collaboratively integrated on the basis of integration pattern. The main advantages of MeCOMA are (1) to reduce software development time and (2) to consistently build reusable production software components.

Purpose: In the context of COVID-19, studies evaluating the adherence of dentists and dental students to infection control are relevant due to their high occupational exposure and risk, as well as their responsibility for disseminating information and good practices. This study evaluated the adherence of dentists and dental students to infection control in the oral radiology field in the setting of the COVID-19 pandemic on different continents. Materials and Methods: This cross-sectional observational study involved individuals who performed intraoral radiographic examinations during the COVID-19 pandemic. The Questionnaire on Infection Control in Oral Radiology was administered virtually using a Google Form. Participants from different continents(the Americas, Africa, Europe, Asia, and Oceania) were recruited. Data were subjected to descriptive analysis and simple and multiple binary regression (5%). Results: There were 582 valid answers, and 68.73% of the participants were from the Americas, 18.90% from Europe, and 12.37% from Asia. The median score for infection control protocols was 94 points for dental students and 104 points for dentists, and participants below the median were considered to have low adherence to infection control in oral radiology. Low access to infection control was found for 53.0% of dentists in the Americas, 34.0% from Europe, and 26.9% from Asia. Conclusion: The adherence to infection control protocols in oral radiology was low even in the face of the COVID-19 pandemic. The results may help improve the awareness of students and professionals, since oral radiology routines have the potential for transmitting COVID-19.

This paper deals with the modeling and control of a microgripper devoted to micromanipulation and microassembly applications and tasks. Based on two collaborative piezoelectric actuators, the microgripper is typified by a high sensitivity to the environment, in particular a high sensitivity to the properties of the manipulated objects. This sensitivity makes the behavior of the microgripper variable and uncertain versus the environment and consequently makes the tasks lose performances. A possible way to overstep that problem is to model the microgripper behavior and its dependency with the environment as perfect as possible and then calculate a controller from this. However, such model is complex to handle and the yielded controllers are often very complex for implementation. In this paper, we propose to use interval models to describe the behavior of the piezoelectric actuators that compose the microgripper. Then a controllers synthesis consisting in combining interval techniques and classical control theory is proposed. Both the position and the force raised in the microgripper are considered. The main advantages of the proposed technique are: 1) ease and natural way to model the uncertainties, 2) the robustness of the synthesized controllers, 3) and the derivation of low order controllers that are easier for implementation relative to those of classical robust control techniques. Finally, the paper presents the application of the controlled microgripper to an automated pick-transport-and-place task of micro-objects. This automated task demonstrates the efficiency of the control technique in micromanipulation and microassembly applications.

It is difficult to observe the potential risks of lifting or turn-over operations in the early stages before a real operation. Therefore, many dynamic simulations have been designed to predict the risks and to reduce the possibility of accidents. These simulations, however, have usually been performed for predetermined and fixed scenarios, so they do not reflect the real-time control of an operator that is one of the most important influential factors in an operation; additionally, lifting or turn-over operations should be a collaboration involving more than two operators. Therefore, this study presents an integrated method for a collaborative simulation that allows multiple workers to operate together in the virtual world. The proposed method is composed of four components. The first component is a dynamic analysis that is based on multibody-system dynamics. The second component is VR (virtual reality) for the generation of realistic views for the operators. The third component comprises the control devices and the scenario generator to handle the crane in the virtual environment. Lastly, the fourth component is the HLA (high-level architecture)-based integrated simulation interface for the convenient and efficient exchange of the data through the middleware. To show the applicability of the proposed method, it has been applied to a block turn-over simulation for which one floating crane and two crawler cranes were used, and an offshore module installation for which a DCR (dual-crane rig) was used. In conclusion, the execution of the proposed method of this study is successful regarding the above two applications for which multiple workers were involved.

Recently, the needs for the development and application of marine robots are increasing as marine accidents occur frequently. However, it is very difficult to acquire the information by utilizing marine robots in the marine environment. Therefore, the needs for the researches of sensor networks which are composed of underwater, surface and aerial robots are increasing in order to acquire the information effectively as the information from heterogeneous robots has less limitation in terms of coverage and connectivity. Although various researches of the sensor network which is based on marine robots have been executed, all of the underwater, surface and aerial robots have not yet been considered in the sensor network. To solve this problem, a collaborative control method based on the acoustic information and image by the sonars of the underwater robot, the acoustic information by the sonar of the surface robot and the optical image by the camera of the static-floating aerial robot is proposed. To verify the performance of the proposed method, the collaborative control of a MUR(Micro Underwater Robot) with an OAS(Obstacle Avoidance Sonar) and a SSS(Side Scan Sonar), a MSR(Micro Surface Robot) with an OAS and a BMAR(Balloon-based Micro Aerial Robot) with a camera are executed. The test results show the possibility of real applications and the need for additional studies.

This paper suggests the target tracking method improved for the collaboration of the quad rotor type UAV (Unmanned Aerial Vehicle) and omnidirectional Unmanned Ground Vehicle. If UAV shakes or UGV moves rapidly, the existing method generates a phenomenon that the tracking object loses the tracking target. To solve the problems, we propose an algorithm that can track continually when they lose the target. The proposed algorithm stores the vector of the landmark. And if the target was lost, the control signal was inputted so that the landmark could move continuously to the direction running out. Prior to the experiment, Proportional and integral control were used in 4 motors in order to calibrate the Heading value of the omnidirectional mobile robot. The landmark of UGV was recognized as the camera adhered to UAV and the target was traced through the proportional-integral-derivative control. Finally, the performance of the target tracking controller and proposed algorithm was evaluated through the experiment.

현재 많은 사용자들이 정보 교육과 전달을 위하여 CD-ROM 이나 인터넷 환경과 그것의 응용을 이용 한다. 하지만, 현재 상황에서의 정보는 한 방향으로만 전달되며 사용자간 정보 공유와 공유된 정보에 대한 설명 수단은 극히 제한되어 있다. 본 논문에서 제안하는 시스템은 공유된 미디어 객체에 대하여 Mouse Recording 및 Player를 통하여 공동작업에 참여한 사용자들이 동일 View를 통해 참조하고 고가의 어플리케이션을 직접 실습 및 참조할 수 있도록 설계, 구현되었다. 또 피교육자들의 컴퓨터를 제어함으로 분산 시스템 환경 하에서 원격교육 등에서 정보 교환 및 학습 수단으로 사용될 수 있다.

협동로봇은 4차 산업혁명에서 제시하고 있는 생산시스템 중 하나로 작업자의 정교한 손기술과 로봇의 단순 반복작업 능력을 조합하여 효율성을 극대화할 수 있는 시스템이다. 또한, 작업자와 로봇 간의 작업공간 공유에서 발생하는 안전문제의 해결과 함께 효율적인 인터페이스 방법 개발에 대한 연구가 지속적으로 진행되고 있다. 본 연구에서는 이를 위하여 작업자의 편리성과 집중도를 강화하기 위해 작업자의 수신호를 인식하여 로봇을 제어하는 방법을 제시하였으며 안전공간의 개념을 도입하여 작업자의 안전을 확보하였다. 이를 구현하기 위하여 로봇제어, PLC, 영상처리, 기계학습, ROS 등 다양한 기술을 사용하였다. 또한 이를 교육매체로 활용하기 위하여 제시된 기술들의 역할과 인터페이스 방법을 정의하여 제시하였다. 학습자들은 소개된 여러 기술들을 연계하여 시스템을 구축하고 조정하는 일을 수행한다. 따라서 현장에서 필요한 기술의 필요성을 인식시키고 이에 대한 심화 학습을 유도할 수 있는 큰 장점이 있다. 또한 문제를 제시한 뒤 스스로 문제를 해결하는 방법을 모색하는 형태로 진행해 자기 주도적으로 학습할 수 있도록 유도할 수 있다. 이를 통해 4차 산업혁명의 주요 기술들을 학습하고 다양한 문제에 대한 해결 능력을 향상시킬 수 있다.

A collaborative robot(Cobot) is one of the production systems presented in the 4th industrial revolution and are systems that can maximize efficiency by combining the exquisite hand skills of workers and the ability of simple repetitive tasks of robots. Also, research on the development of an efficient interface method between the worker and the robot is continuously progressing along with the solution to the safety problem arising from the sharing of the workspace. In this study, a method for controlling the robot by recognizing the worker's hand signal was presented to enhance the convenience and concentration of the worker, and the safety of the worker was secured by introducing the concept of a safety zone. Various technologies such as robot control, PLC, image processing, machine learning, and ROS were used to implement this. In addition, the roles and interface methods of the proposed technologies were defined and presented for using educational media. Students can build and adjust the educational media system by linking the introduced various technologies. Therefore, there is an excellent advantage in recognizing the necessity of the technology required in the field and inducing in-depth learning about it. In addition, presenting a problem and then seeking a way to solve it on their own can lead to self-directed learning. Through this, students can learn key technologies of the 4th industrial revolution and improve their ability to solve various problems.

대규모 분산 협동 환경에서 다수의 참여자에게 상호 작용 성능을 지원해 주기 위한 확장성 있는 예측 기반 동시성 제어 방법을 제안한다. 예측 기반 동시성 제어는 낙관적 (optimistic) 방법과 같이 참여자들에게 실시간 상호 작용 성능을 제공하고, 비관적 pessimistic) 방법과 같이 잠금(lock)이 부인될 경우가 복구가 필요없다. 본 논문에서는 소유자 예측을 위하여 객체 기반 다중 전송 그룹을 개발했다. 관심있는 객체 주변에 있는 사용자들만 그 객체 다중전송 그룹에 할당된 주소에 참여함으로써 소유권 예측을 위한 소유권 요청을 할 수 있다. 이 방식에서는 소유자는 가상 영역내의 모든 사용자 대신 이 다중 전송 그룹에 참여하고 있는 사용자로부터만 메시지를 받으므로 소유자가 받는 메시지 수는 현저히 감소되어 소유자는 요청 처리 시간이 줄어들고 따라서 보다 더 정확한 예측을 할 수 있다. 분석을 통하여 제안된 동시성 제어 방식이 대규모 가상 환경에서 갖는 효율성과 확장성을 증명한다.

협력 시스템은 컴퓨터의 성능 향상과 네트워크 기술의 발전으로 인하여 분산 환경에서 다수의 사람들이 프로젝트나 어떤 작업을 동시에 수행이 가능하도록 하는 기술이다. 분산 환경과 개방형 정보 통신망을 이용하는 협력 시스템은 정보의 신뢰성이 보장되고 안전한 서비스를 제공해야 한다. 또한, 협력 시스템은 공유 객체 기술을 기반으로 함에 따라 공유 객체에 대한 보안 기술의 개발은 절대적으로 필요하다. 특히, 협력 시스템의 보안은 기존의 보안 정책을 그대로 적용하기보다는 각각의 협력 시스템의 특성에 맞게 새롭게 구성되어져야 한다. 본 논문은 실시간 산업 디자인 협력 시스템에서의 보안 프레임워크 중 접근 제어 프레임워크 부분에 대하여 논하고자 한다. 접근 제어는 사용자 정보, 세션 정보, 공유 객체 정보에 대한 접근 제어로 구성되며 사용자 정보 접근제어와 세션의 접근제어는 접근자의 접근 정보에 의해 정의된 규칙에 따른 정보에 접근을 제어하며 공유 객체 접근 제어는 공동 작업을 원활히 하기 위해 주체와 객체사이의 정보를 이용하여 제어하는 특징이 있다.

WebDAV(Web-based Distributed Authoring and Versioning)는 웹 통신 프로토콜로서 인터넷을 통하여 다양한 콘텐츠의 비동기적인 협업 저작을 지원한다. 따라서 WebDAV를 지원하는 다양한 종류의 서버들은 상호간의 협업 작업이 가능하다. 특히 WebDAV의 접근 제어 프로토콜은 특정 자원에 대한 접근 제어 권한을 정의하기 위하여 표준 Privilege들을 정의하고 있다. 본 논문에서는 웹기반 협업시스템의 핵심 기능인 팀 작업장과 공개 작업장의 자원에 접근할 때, 사용자의 권한과 작업장의 특성 그리고 자원의 특징에 따라 접근 제어 관리를 할 수 있도록 접근 제어 기법을 설계하였다. 특히 공개 작업장은 파일 올리기만 가능한 작업장, 내려받기만 가능한 작업장, 올리기/내려받기 가능한 작업장과 같이 성격이 다양하다. 이를 지원하기 위하여 작업장내 파일에 대한 접근 권한을 구체적으로 설계함으로써 협업작업을 체계적이고 안정적으로 지원할 수 있다.

본 연구는 한국 언론 환경에서 협업 저널리즘이 인식론적 성찰의 기회를 어떻게 제공하는지를 탐구한다. 다섯 언론사가 참여한 ‘언론장악 카르텔’ 공동취재 사례를 심층적으로 분석한 본 연구는 협업 과정에서 기자들의 인식론적 관행이 어떻게 조정되고 변화하는지를 밝힌다. 분석 결과, 협업 저널리즘은 인식론적 위기를 해결하는 대안적 실천일 뿐만 아니라, 참여 기자들의 인식론적 성찰을 촉진하여 저널리즘적 지식과 진실에 대한 이해를 재구성하도록 유도한다. 참여 기자들은 자율성과 공유의 규범을 확립하여 유연하고 지속 가능한 협업 모델을 구축했으며, 이는 각 언론사의 강점을 융합하는 시너지를 발휘했다. ‘신속’하면서도 ‘깊이’있는 보도를 통해 효능감을 느낀 기자들은 협업을 지식 생산 방식으로 내재화하고, 공익을 우선하는 ‘온전한 저널리즘’을 실천할 수 있다고 주장하였다. 이러한 분석을 바탕으로, 본 연구는 협업 저널리즘이 현대적 맥락에서 언론의 제도적 정체성을 재구성하고 규범적 역할을 지속하기 위한 대안적 실천임을 강조하며, 지식 제공자로서의 기자 역할을 재정의할 잠재력을 지닌다고 주장한다.

This study investigates the role of collaborative journalism in facilitating epistemic reflection within the Korean media landscape. An in-depth examination of the “Media Control Cartel” joint reveals how collaboration modifies and transforms journalists’ epistemic practices. The findings demonstrate that collaborative journalism not only provides an alternative practice in response to an epistemic crisis but also promotes epistemic reflexivity, prompting journalists to re-evaluate their understanding of journalistic knowledge and truth. By establishing norms of autonomy and sharing, they developed a flexible and sustainable collaborative model that capitalized on the unique strengths of each participating news organization. Internalizing collaboration as a mode of knowledge production, these journalists, experiencing a sense of efficacy, argued that collaborative journalism transcends merely being an alternative practice, representing a form of ‘better’ journalism that overcomes the persistent competition in the Korean media landscape and prioritizes public interest. Consequently, this study emphasizes collaborative journalism as a strategic choice by journalistic actors to reconstruct institutional identities and uphold the normative role of the press in a contemporary context, ultimately asserting its potential to redefine the journalist’s role as a knowledge provider.

This paper proposes a multi-core cooperative computing structure considering the heterogeneous features of automotive embedded on-chip software. The automotive embedded software has the heterogeneous execution flow properties for various hardware drives. Software developed with a homogeneous execution flow without considering these properties will incur inefficient overhead due to core latency and load. The proposed method was evaluated on an target board on which a automotive MCU (micro-controller unit) with built-in multi-cores was mounted. We demonstrate an overhead reduction when software including common embedded system tasks, such as ADC sampling, DSP operations, and communication interfaces, are implemented in a heterogeneous execution flow. When we used the proposed method, embedded software was able to take advantage of idle states that occur between heterogeneous tasks to make efficient use of the resources on the board. As a result of the experiments, the power consumption of the board decreased by 42.11% compared to the baseline. Furthermore, the time required to process the same amount of sampling data was reduced by 27.09%. Experimental results validate the efficiency of the proposed multi-core cooperative heterogeneous embedded software execution technique.

많은 저작자들이 협력하여 작업을 수행할 수 있는 공동저작 시스템에서는 저작을 위해 객체들을 공유하는 일들이 참여 저작자들 간에 빈번히 발생한다. 따라서 객체 액세스를 위한 경쟁을 최소화하고 객체들의 배타적 사용을 보장해 주는 플로어 제어가 필요하다. 플로어(floor)란 공동저작 참여자에게 부여되는 한 공유자원에 대한 임시 사용 권한이다. 단일세션 환경을 위한 플로어 제어 기법들은 여러 문헌에서 찾아 볼 수 있으나 다중세션 환경을 위한 기법들은 거의 찾아 볼 수가 없다. 다중 세션 환경에서는 한 객체가 여러 세션에서 동시에 공유될 수 있다. 본 논문은 다중 세션 환경에서의 객체 공유로 인한 문제들의 해결을 위해 대표의장(chair-of-chair) 방식의 플로어 제어 기법을 제안한다. 기존의 의장형 방식을 확장한 이 방식에는 세션 의장들 중에서 선출된 대표의장이 존재한다.

The sharing of objects for authoring frequently occurs among participating users in a cooperative authoring system where many users can collaborate. Floor control is therefore needed not only for minimizing the race condition during object accesses but also for ensuring the exclusive use of objects. A floor is a temporary access right that is given to a participating user who wants to use a shared object. Although the floor control methods for a single session environment can be found in various literature, those methods for a multi-session environment can hardly be found. In a multi-session environment, an object can be shared by multiple sessions. As a solution to the problems due to object sharing in such an environment, this paper presents a floor control method based on the chair-of-chair guidance. This method is an extension of those based on traditional chair guidance; the chair-of-chair elected among session chairs exists in this method.