• 한국멀티미디어학회논문지
• /
• 제8권9호
• /
• pp.1163-1176
• /
• 2005

웹은 가장 커다란 분산 정보저장소로서 빠른 속도로 성장했으나, 웹의 정보를 읽고 이해하는 데는 본질적으로 한계가 있다. 웹의 이러한 환경에서 사용자의 순회패턴(traversal Patterns)을 탐사하는 것은 시스템 설계나 정보서비스 제공 측면에서 중요한 문제이다. 본 논문에서는 세션에 나타나는 페이지들간의 연관성 정보를 활용하여 빈발 k-페이지집합을 탐사하여 추천 페이지집합을 생성함으로써 효율적인 웹 정보서비스를 제공할 수 있는 Web Page Recommend(WebPR) 알고리즘[11]을 화장한다. 화장된 내용은 WebPRl(A) 알고리즘을 추가하였으며, WebPR(T)에서 윈도우 개념을 도입한 새로운 winWebPR(T) 알고리즘을 제안하고 있다. 두개의 화장된 알고리즘을 포함하여 두개의 실제 웹로그(Weblog) 데이터에 대해 실험 결과에서 알 수 있듯이 윈도우 개념을 도입한 winWebPR(T) 알고리즘이 세션에 나타나는 페이지들간의 모든 연관성 정보를 활용함으로써 가장 우수한 성능을 보였다.

• 한국콘텐츠학회논문지
• /
• 제11권5호
• /
• pp.75-83
• /
• 2011

어스팩트 지향 프로그래밍은 시스템에서 크로스커팅 개념을 추출하고 소프트웨어 모듈화를 통하여 기능의 분산과 코드의 혼란을 해결하기 위한 패러다임이다. 현존하는 어스팩트 개발 방법은 크로스커팅 대상 영역을 추출에 어려움이 있기 때문에, 어스팩트 마이닝을 적용하기가 쉽지 않다. 어스팩트 마이닝에서는 기존 프로그램의 리팩토링 요소를 크로스커팅 영역으로 변환하는 기술이 필수적이다. 본 논문에서는 리팩토링에 적합한 크로스커팅 영역 자동 추출을 위한 시스템에서 크로스커팅 개념을 추출하기 위한 어스팩트 마이닝 방법을 제안한다. 소스 모듈의 추상 구문구조 명세를 이용하여, 모듈의 구조적 중복 관계 요소를 추출한다. Apriori 알고리즘을 통하여 중복 구문트리를 생성하고, 크로스커팅 영역 대상인 중복된 소스 모듈을 자동 생성, 최적화 할 수 있다. Berkeley Yacc의 berbose.c 모듈을 제안하는 마이닝 프로세스에 적용해 본 결과, 원본 대비 9.47%의 길이와 부피의 감소하였고, CCFinder 대비 4.92%의 길이 감소, 5.11%의 부피 감소 효과를 확인하였다.

• 한국정보시스템학회지:정보시스템연구
• /
• 제29권2호
• /
• pp.221-242
• /
• 2020

Purpose This study collects data of the recently activated online black market and analyzes it to present a specific method for preparing for a hacking attack. This study aims to make safe from the cyber attacks, including hacking, from the perspective of individuals and businesses by closely analyzing hacking methods and tools in a situation where they are easily shared. Design/methodology/approach To prepare for the hacking attack through the online black market, this study uses the routine activity theory to identify the opportunity factors of the hacking attack. Based on this, text mining and social network techniques are applied to reveal the most dangerous areas of security. It finds out suitable targets in routine activity theory through text mining techniques and motivated offenders through social network analysis. Lastly, the absence of guardians and the parts required by guardians are extracted using both analysis techniques simultaneously. Findings As a result of text mining, there was a large supply of hacking gift cards, and the demand to attack sites such as Amazon and Netflix was very high. In addition, interest in accounts and combos was in high demand and supply. As a result of social network analysis, users who actively share hacking information and tools can be identified. When these two analyzes were synthesized, it was found that specialized managers are required in the areas of proxy, maker and many managers are required for the buyer network, and skilled managers are required for the seller network.

• Safety and Health at Work
• /
• 제7권1호
• /
• pp.12-17
• /
• 2016

Background: The mining industry is considered as one of the most dangerous and hazardous industries and the need for effective and efficient occupational health and safety management is critical to safeguard workers and the industry. Despite the dangers and hazards present in the mining industry, only few studies have focused on how occupational health and safety and turnover intentions in the mines. Method: The study suing a cross-sectional survey design collected quantitative data from the 255 mine workers that were conveniently sampled from the Ghanaian mining industry. The data collection tools were standardized questionnaires that measured occupational health and safety management and turnover intentions. These scales were also pretested before their usage in actual data collection. Results: The correlation coefficient showed that a negative relationship existed between dimensions of occupational health and safety management and turnover intention; safety leadership (r = -0.33, p < 0.01); supervision (r = -0.26, p < 0.01); safety facilities and equipment (r = -0.32, p < 0.01); safety procedure (r = -0.27, p < 0.01). Among these dimensions, safety leadership and safety facility were significant predictors of turnover intention, (${\beta}=-0.28$, p < 0.01) and (${\beta}=-0.24$, p < 0.01) respectively. The study also found that turnover intention of employees is heavily influenced by the commitment of safety leadership in ensuring the effective formulation of policies and supervision of occupational health and safety at the workplace. Conclusion: The present study demonstrates that safety leadership is crucial in the administration of occupational health and safety and reducing turnover intention in organizations.

• Geomechanics and Engineering
• /
• 제29권6호
• /
• pp.697-706
• /
• 2022

In order to explore the stable anchoring conditions of coal side under the mining disturbance of soft section coal pillar in Wangcun Coal Mine of Chenghe Mining Area, the distribution model of the anchoring support pressure at the coal pillar side was established, using the strain-softening characteristics of the coal to study the distribution law of anchoring coal side support pressure. The analytical solution for the reinforcement anchorage stress in the coal pillar side was derived with the inelastic state mechanical model. The results show that the deformation angle of the roadway side and roof increases with the roof subsidence due to the mining influence at the adjacent working face, the plastic deformation zone extends to the depth of the coal side, and the increase of anchorage stress can effectively control the roof subsidence and further deterioration of plastic zone. The roadway height and the peak support pressure have a certain influence on the anchorage stress, the required anchorage stress of the coal side rises with the roadway height and the peak support pressure. The required anchorage stress of the coal pillar side decreases as the cohesion between the coal seam and the roof and floor and the anchor length increases. Then, applied the research result to Wangcun coal mine in Chenghe mining area, the design of anchor cable reinforcement support was proposed for the section of coal pillars side that has been anchored and deformed, which achieved great results and effectively controlled the convergence and deformation of the side, providing a safety guarantee for the roadway excavation and mining.

• Structural Engineering and Mechanics
• /
• 제81권2호
• /
• pp.205-217
• /
• 2022

The thermodynamic properties of shaft lining concrete (SLC) are important evidence for the design and construction, and the spatial variability of concrete materials can directly affect the stochastic thermal analysis of the concrete structures. In this work, an array of field experiments of the concrete materials are carried out, and the statistical characteristics of thermophysical parameters of SLC are obtained. The coefficient of variation (COV) and scale of fluctuation (SOF) of uncertain thermophysical parameters are estimated. A three-dimensional (3-D) stochastic thermal model of concrete materials with heat conduction and hydration heat is proposed, and the uncertain thermodynamic properties of SLC are computed by the self-compiled program. Model validation with the experimental and numerical temperatures is also presented. According to the relationship between autocorrelation functions distance (ACD) and SOF for the five theoretical autocorrelation functions (ACFs), the effects of the ACF, COV and ACD of concrete materials on the uncertain thermodynamic properties of SLC are analyzed. The results show that the spatial variability of concrete materials is subsistent. The average temperatures and standard deviation (SD) of inner SLC are the lowest while the outer SLC is the highest. The effects of five 3-D ACFs of concrete materials on uncertain thermodynamic properties of SLC are insignificant. The larger the COV of concrete materials is, the larger the SD of SLC will be. On the contrary, the longer the ACD of concrete materials is, the smaller the SD of SLC will be. The SD of temperature of SLC increases first and then decreases. This study can provide a reliable reference for the thermodynamic properties of SLC considering spatial variability of concrete materials.

• 인터넷정보학회논문지
• /
• 제24권5호
• /
• pp.51-66
• /
• 2023

본 논문에서는 비즈니스 프로세스 모델의 생명주기관리를 지원하는 대표적인 지식발견기술인 프로세스 마이닝과 지식개선기술인 프로세스 리엔지니어링 접근방법을 기반으로 하는 새로운 유형의 프로세스 발견 프레임워크를 제안한다. 또한, 제안된 프레임워크를 기반으로 하는 프로세스 마이닝 시스템을 개발하고, 이를 통한 실험적 검증을 수행한다. 실험적 효과검증에 적용된 프로세스 실행 이벤트 로그를 특별히 프로세스 빅-로그(Process BIG-Logs)라고 정의하고, 분산 비즈니스 프로세스 관리 시스템의 로깅메커니즘과 연계된 조각-실행로그이력들을 클러스터링하는 전처리과정을 거친 마이닝의 입력데이터세트로 활용한다. 결과적으로, 본 논문에서는 구조적 정보제어넷기반 프로세스 마이닝 알고리즘인 ρ-알고리즘을 개선한 제어경로기반 프로세스 그룹 발견 알고리즘과 프레임워크를 설계 및 구현하고, 구현된 시스템을 이용하여 제안한 알고리즘과 프레임워크의 정확성을 실험적으로 검증한다.

• 한국의류산업학회지
• /
• 제25권5호
• /
• pp.549-559
• /
• 2023

Along with the transition to the fourth industrial revolution, the possibility of metaverse-based innovation in the fashion field has been confirmed, and various applications are being sought. Therefore, this study performs meaning structure analysis and discusses the prospects of meta fashion using big data. From 2020 to 2022, data including the keyword "metaverse + fashion design" were collected from portal sites (Naver, Daum, and Google), and the results of keyword frequency, N-gram, and TF-IDF analyses were derived using text mining. Furthermore, network visualization and CONCOR analysis were performed using Ucinet 6 to understand the interconnected structure between keywords and their essential meanings. The results were as follows: The main keywords appeared in the following order: fashion, metaverse, design, 3D, platform, apparel, and virtual. In the N-gram analysis, the density between fashion and metaverse words was high, and in the TF-IDF analysis results, the importance of content- and technology-related words such as 3D, apparel, platform, NFT, education, AI, avatar, MCM, and meta-fashion was confirmed. Through network visualization and CONCOR analysis using Ucinet 6, three cluster results were derived from the top emerging words: "metaverse fashion design and industry," "metaverse fashion design and education," and "metaverse fashion design platform." CONCOR analysis was also used to derive differentiated analysis results for middle and lower words. The results of this study provide useful information to strengthen competitiveness in the field of metaverse fashion design.

• Journal of Power Electronics
• /
• 제16권4호
• /
• pp.1598-1611
• /
• 2016

In some special occasions with strict size requirements, such as mine hoists, improving the design accuracy of the forced-air cooling systems of NPC three-level inverters is a key technology for improving the power density and decreasing the volume. First, a fast power-loss calculation method was brought. Its calculation principle introduced in detail, and the computation formulas were deduced. Secondly, the average and dynamic power losses of a 1MW mine hoist acting as the research target were analyzed, and a forced-air cooling system model based on a series of theoretical analyses was designed with the average power loss as a heat source. The simulation analyses proves the accuracy and effectiveness of this cooling system during the unit lifting period. Finally, according to an analysis of the periodic working condition, the maximum power-loss range of a NPC three-level inverter under multi cycle operation was obtained and its dynamic power loss was taken into the optimized cooling system model as a heat source to solve the power device damage caused by instantaneous heat accumulation. The effectiveness and feasibility of the optimization design based on the dynamic power loss calculation of the maximum power-loss range was proved by simulation and experimental results.

• Coupled systems mechanics
• /
• 제2권1호
• /
• pp.23-51
• /
• 2013

An analytical algorithm for the estimation of the resistance forces exerted on the dipper of a cable shovel and the specific energy consumed in the cutting-loading process is presented. Forces due to payload and to cutting of geomaterials under given initial conditions, cutting trajectory of the bucket, bucket's design, and geomaterial properties are analytically computed. The excavation process has been modeled by means of a kinematical shovel model, as well as of dynamic payload and cutting resistance models. For the calculation of the cutting forces, a logsandwich passive failure mechanism of the geomaterial is considered, as has been found by considering that a slip surface propagates like a mixed mode crack. Subsequently, the Upper-Bound theorem of Limit Analysis Theory is applied for the approximate calculation of the maximum reacting forces exerted on the dipper of the cable shovel. This algorithm has been implemented into an Excel$^{TM}$ spreadsheet to facilitate user-friendly, "transparent" calculations and built-in data analysis techniques. Its use is demonstrated with a realistic application of a medium-sized shovel. It was found, among others, that the specific energy of cutting exhibits a size effect, such that it decreases as the (-1)-power of the cutting depth for the considered example application.