Development of a Forensic Analyzing Tool based on Cluster Information of HFS+ filesystem

Cho, Gyu-Sang The Institute of Internet 2021 International Journal of Internet, Broadcasting an Vol.13 No.3

File system forensics typically focus on the contents or timestamps of a file, and it is common to work around file/directory centers. But to recover a deleted file on the disk or use a carving technique to find and connect partial missing content, the evidence must be analyzed using cluster-centered analysis. Forensics tools such as EnCase, TSK, and X-ways, provide a basic ability to get information about disk clusters, but these are not the core functions of the tools. Alternatively, Sysinternals' DiskView tool provides a more intuitive visualization function, which makes it easier to obtain information around disk clusters. In addition, most current tools are for Windows. There are very few forensic analysis tools for MacOS, and furthermore, cluster analysis tools are very rare. In this paper, we developed a tool named FACT (Forensic Analyzer based Cluster Information Tool) for analyzing the state of clusters in a HFS+ file system, for digital forensics. The FACT consists of three features, a Cluster based analysis, B-tree based analysis, and Directory based analysis. The Cluster based analysis is the main feature, and was basically developed for cluster analysis. The FACT tool's cluster visualization feature plays a central role. The FACT tool was programmed in two programming languages, C/C++ and Python. The core part for analyzing the HFS+ filesystem was programmed in C/C++ and the visualization part is implemented using the Python Tkinter library. The features in this study will evolve into key forensics tools for use in MacOS, and by providing additional GUI capabilities can be very important for cluster-centric forensics analysis.

유아 동기 유형 평가도구 적용 군집화 및 사례분석

유구종 ( Yoo Ku Jong ),최승연 ( Choi Seung Yeon ),조희정 ( Cho Hee Jung ),성은영 ( Sung Eun Young ) 한국어린이문학교육학회 2017 어린이문학교육연구 Vol.18 No.1

본 연구는 유아 동기 유형 평가도구에 의해 평가가 실시되었을 때 유아의 동기 유형이 어떠한 하위 군집의 유형으로 분류 되는지 살펴보고 구체적인 사례를 통해 하위군집의 특성을 살펴봄으로써 현장 적용성을 비롯한 생태학적 타당도를 제고하는데 그 목적이 있다. 이를 위해 본 연구에서는 614명의 유아를 대상으로 유아 동기 유형 평가도구를 적용하여 군집분석을 실시하여 군집화 된 군집유형을 명명하고, 성별과 연령에 따라 군집 유형 차이를 검증하였다. 또한 만 5세 유아 20명으로 구성된 1개 학급을 대상으로 군집화를 통해 도출한 군집 유형으로 연구대상을 유형별로 나누어 군집유형에 따른 행동 특성을 파악하고자 사례분석을 실시하였다. 이를 위해 계층적 군집분석, K-means 군집분석의 총 2회에 걸친 군집분석을 통해 3개의 군집으로 유아의 동기 유형을 군집화 하였다. 군집 1은 동기 유형에 있어 내적 동기가 월등히 높고 외적 동기와 무동기는 매우 낮은 것으로 나타나 고(高)내적 동기형으로 명명되었고, 군집 2는 내적 동기가 군집 1과 군집 3에 비하여 절반수준에 머물렀고, 외적 동기와 무동기의 경우에도 군집 3에 비해 저조한 수준으로 나타나 저(低)동기형으로 명명하였다. 군집 3의 경우는 내적 동기는 군집 1과 비슷한 수준으로 나타났으나 무동기 유형이 가장 높게 나타나 복합동기형으로 명명하였다. 성별과 연령에 따른 차이분석은 모두 차이가 없는 것으로 나타나 동기는 연령과 성별에 관계없는 개인의 일반적인 특성인 것으로 나타났다. 사례분석에서는 군집분석을 통해 군집화 된 군집별 특징이 사례에 부합되어 발현되는 것으로 나타났다. For clustering of infant motivation types, hierarchical cluster analysis and K-means cluster analysis were conducted. As a result, infant motivation types were classified into 3 clusters. As for the motivation types of cluster 1, internal motivation was significantly outstanding while external motivation and internal motivation were quite insignificant. Internal motivation of cluster 2 was as low as a half of those of cluster 1 and cluster 3. External motivation and no-motivation as well were lower than those of cluster 3. Internal motivation of cluster 3 was similar to that of cluster 1, but the level of no-motivation was the highest. Accordingly, in this study, cluster 1 is called the high internal motivation type, cluster 2 the low motivation type, and cluster 3 the complex motivation type, respectively, to represent the attributes of the clusters. As a result of analyzing the differences among the cluster types depending on the sex and age, it was determined that there was no significant difference depending on the sex and age of the infant. As a case study on the clusters of motivation types, anecdote recordings were conducted for 12 weeks and analyzed systematically. As a result, it was determined that young children in the high internal motivation type cluster were seeking self-satisfaction and satisfying their internal curiosity while young children in the low motivation type were following the instruction of others and expected extrinsic rewards. Young children in the complex motivation type cluster were sensitive to external stimuli and would act at a moderate level.

Enhancing Clustering Algorithm with Initial Centroids in Tool Wear Region Recognition

Nur Adilla kasim,M. Z. Nuawi,J. A. Ghani,Muhammad Rizal,N. A. Ngatiman,C. H. C. Haron 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.22 No.5

Autonomous manufacturing allows the system to distinguish between a mild, normal and total failure in tool condition. K-means clustering has become the most applied algorithm in discovering classes in an unsupervised scenario. Nevertheless, the algorithm is sensitive to the initial centroids giving various solution every time the system updating. Regular unsupervised K-means is refocused as semi-supervised Fixum K-means. It is embedded with a new tactic to recapture the K value and new initial seedings computation to kick off the system until it converges. Force components of cutting force F c , thrust force F t and perpendicular cutting force F cn were extracted from Neo-MoMac cutting force measurement device. The analysis threshold represents a natural-sorted input vector as Z -rot coefficient ( R Z ) corresponds to the number of cutting accomplish a strong correlation ( R 2 = 0.8511) over wear evolution. The clustering system adopted a new calculation of initial centroids has successfully determined the three regions for only a single assignment and achieving the optimal distance squared through eight given data sets. It is conflicting with the standard K-means that return different clustering structure in each run, while K-means + + replicates several times to achieve minimum objective function. During the course, F-Km delivered robust and consistence clustering results of 85% accuracy over standard K-means and four times converges faster than K-means + + . The silhouette value average score is 0.8504 (highest score is 0.9207) of how well-distributed the resulting clusters. The clustering system has identified the tool to stop cutting at approximate VB = 0.213 mm before the tool condition enters the failure region of abnormal phase ( VB < 0.250 mm ).s The proposed system functioned effectively in clustering the data obtained from cutting tests performed within a reasonable range of wear stages. Precision and robustness analysis have proved F-km to score 100% attainment for clustering assignment output and replicability. In contrast, K-means scored 76.3% for precision and ranging from 5 to 33% for robustness. Whereas, K-means + + scored 33% for robustness and a higher chance of time complexity compared to F-km. F-Km is found to be more accurate, time savvy and robust than standard K-means and K-means + + . Therefore, the method can be reliably used for observing tool wear state recognition without training and equivocate traditional direct tool wear.

Scheduling In-Line Multiple Cluster Tools

Hyun-Jung Kim,Jun-Ho Lee,Sunhee Baik,Tae-Eog Lee Institute of Electrical and Electronics Engineers 2015 IEEE transactions on semiconductor manufacturing Vol.28 No.2

<P>A cluster tool which is widely used for wafer fabrication processes consists of several processing modules (PMs), a transport robot, loadlocks, and an equipment front-end module (EFEM) in which a wafer cassette is loaded and unloaded. A wafer cassette with 25 identical wafers is transported by an overhead hoist transfer (OHT) between cluster tools and stored in a stocker when the corresponding tool is not available. Due to a large number of tools and wafer cassettes in a fab, it is extremely complicated to operate OHTs so as to minimize the idle times of the tools. Therefore, fabs tend to reduce the transportation tasks by arranging tools in a line with a buffer. In this paper, we introduce a new system called in-line multiple cluster tools which have many challenging operation issues for researchers and propose simple and practical methods to operate the system. We first develop mixed integer programming models to assign wafers to parallel PMs and derive a priority rule-based scheduling policy for the EFEM operation while minimizing the makespan of producing 25 wafers. We also propose multimode operation in which a component tool in the system processes multiple wafer types at the same time to improve the utilization rate of the tool.</P>

클러스터 설비제어 애플리케이션의 아키텍처 및 구현

한용희 ( Yong Hee Han ) 대한설비관리학회 2012 대한설비관리학회지 Vol.17 No.2

A cluster tool consists of several single-wafer processing modules (PMs) and a transfer module (TM) based on a wafer-handling robot. This paper presents a systematic object-oriented architecture for designing and implementing cluster tool control applications. This architecture incorporates management functions for process, log, alarm, file, and I/O which are critical in cluster tool control applications but have not been discussed in other papers. This paper also discusses implementation issues as well as the real control application which has been implemented and tested on a real cluster tool.

On 5-Axis Freeform Surface Machining Optimization: Vector Field Clustering Approach

My Chu A,Bohez Erik L J,Makhanov Stanlislav S,Munlin M,Phien Huynh N,Tabucanon Mario T Society for Computational Design and Engineering 2005 International Journal of CAD/CAM Vol.5 No.1

A new approach based on vector field clustering for tool path optimization of 5-axis CNC machining is presented in this paper. The strategy of the approach is to produce an efficient tool path with respect to the optimal cutting direction vector field. The optimal cutting direction maximizes the machining strip width. We use the normalized cut clustering technique to partition the vector field into clusters. The spiral and the zigzag patterns are then applied to generate tool path on the clusters. The iso-scallop method is used for calculating the tool path. Finally, our numerical examples and real cutting experiment show that the tool path generated by the proposed method is more efficient than the tool path generated by the traditional iso-parametric method.

Bonded-cluster simulation of tool-rock interaction using advanced discrete element method

Weiji Liu,Xiaohua Zhu,Yun-Lai Zhou,Tao Li,Xiangning Zhang 국제구조공학회 2019 Structural Engineering and Mechanics, An Int'l Jou Vol.72 No.4

The understanding of tool-rock interaction mechanism is of high essence for improving the rock breaking efficiency and optimizing the drilling parameters in mechanical rock breaking. In this study, the tool-rock interaction models of indentation and cutting are carried out by employing the discrete element method (DEM) to examine the rock failure modes of various brittleness rocks and critical indentation and cutting depths of the ductile to brittle failure mode transition. The results show that the cluster size and inter-cluster to intra-cluster bond strength ratio are the key factors which influence the UCS magnitude and the UCS to BTS ratio. The UCS to BTS strength ratio can be increased to a more realistic value using clustered rock model so that the characteristics of real rocks can be better represented. The critical indentation and cutting depth decrease with the brittleness of rock increases and the decreasing rate reduces dramatically against the brittleness value. This effort may lead to a better understanding of rock breaking mechanisms in mechanical excavation, and may contribute to the improvement in the design of rock excavation machines and the related parameters determination.

영어 학술논문 코퍼스의 키클러스터 구조와 기능

이성민,김신호,장세은 한국중앙영어영문학회 2015 영어영문학연구 Vol.57 No.1

This study aims to investigate structural and functional distributions of English key clusters used in the biomedical academic journals written by English native scholars and Korean scholars through a quantitative method used in corpus linguistics. We focused on key clusters in order to find more genre specific lexical bundles than common lexical bundles shared with a general corpus. In order to explore the distributions of the key clusters used by English native scholars and Korean scholars, we conducted the structural and functional classification by using Wordsmith tools 6.0. We also used the Chi-square test to find out whether or not there are any significant differences between grammatical structures and discourse functions of key clusters. In addition, we visualized residuals of the statistical results by using an R program. The results showed that the proportions of structures between English native scholars and Korean scholars showed no statistical differences. However, Korean scientists used more reference key clusters and less stance key clusters.

클러스터 툴의 예방유지보수 스케줄링 모형

이현,박유진,허선 대한산업공학회 2012 산업공학 Vol.25 No.1

This paper considers the preventive maintenance scheduling problem of the cluster tool which is one of the most important manufacturing equipments in the next-generation semiconductor production environment. We define a random process that expresses the successive amount of chemicals accumulating inside the tool. Based on the renewal theory, we find the expected value and probability distribution of the time that the amount of accumulated chemicals exceeds a predetermined level. For a given probability that the accumulated chemicals exceeds the predetermined level we present a method to obtain the number of chamber operations to perform the preventive maintenance of that chamber. In addition, a method to get the preventive maintenance schedule for the whole cluster tool is presented. A numerical example is provided to illustrate our method.

국어과 교육과정 성취기준 구현 패러다임의 점검과 전망

정은아(Chung, Eun-ah) 국어교육학회 2017 국어교육연구 Vol.63 No.-

The purpose of this paper is to check the paradigm of the Korean language curriculum implementation and the expected improvement direction. During the 10 revisions, major changes in the curriculum of recent years are introduction of the grade cluster to improve the irrationality of one year grade system hierarchy and repeated attempt of a quantitative reduction of 20% with the aim of optimizing the amount of learning. Also, textbooks in the Korean language education have the status of the curriculum. Therefore, this study divides the way in which the curriculum is implemented in the textbook before and after introduction of the grade cluster. And the fact that the language teaching of Korean education in the past has been evaluated as ‘a view of language tool’, meanwhile the fact that the purpose of teaching and learning is aiming at ‘whole language’ is examined. Now it is necessary to change the paradigm to the ‘a view of whole language’. It is time to escape from the implementation method of achieving one achievement criterion directly in a single unit based on the language tool paradigm. Now, the textbooks should be able to materialize the integration between the areas or between the achievement criteria within the framework of good works. When implementing the achievement standards as learning objectives, it is necessary to have a flexible attitude according to importance by means of the implementation of the time and the level of the attention matter.