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A Study on the Retrieval Algorithms for Atmospheric Parameters from FORMOSAT-3/COSMIC Occultation Data

  • Yeh, Wen-Hao;Chiu, Tsen-Chieh;Huang, Cheng-Yung;Liou, Yuei-An
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.312-315
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    • 2006
  • Radio occultation technique has been used in planetary science to obtain reliable and accurate temperature profiles of the other planets' atmosphere for decades. It relies on the fact that radio waves are bent and delayed due to the gradient of atmospheric refractivity along-ray-path. With the advent of Global Positioning System (GPS), it becomes possible to retrieve the refractivity and temperature profiles of the Earth's atmosphere from the occultation data. We have developed a retrieval algorithm and compared the results of our algorithm with the data of CHAMP to verify the accuracy of our algorithm is good enough. In our algorithm, there are some smoothing steps when retrieving. We analysis the data of FORMOSAT-3 and compare the results with and without smoothing and the results of TACC to see is there any phenomenon deleted after smoothing.

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Development of real-time database handling system for turning operation (선삭공정용 데이터베이스의 실시간 운용 시스템의 개발)

  • 이형국;이석희
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10a
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    • pp.170-174
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    • 1990
  • The information with regard to the working range of lathe, cutting tool, cutting condition is managed as Database system for turning operation as one part of CAM system. Data with regard to the working range of lathe, cutting tool, cutting condition are stored by the DBMS(Data Base Management System) and can be added, modified, deleted and retrieved for realtime usages. Data stored in Database system are searched to select the most proper cutting tool and cutting condition with the input data fed from the design stage. Codes in regards to tool shape are displayed on graphic mode for easy selection for user and thus presents a good decision support for tool selection. The system developed in this work is operated by the pull down menu on the IBM PC/AT personal computer, or compatible series.

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Verifiable Could-Based Personal Health Record with Recovery Functionality Using Zero-Knowledge Proof (영지식 증명을 활용한 복원 기능을 가진 검증 가능한 클라우드 기반의 개인 건강기록)

  • Kim, Hunki;Kim, Jonghyun;Lee, Dong Hoon
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.30 no.6
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    • pp.999-1012
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    • 2020
  • As the utilize of personal health records increases in recent years, research on cryptographic protocol for protecting personal information of personal health records has been actively conducted. Currently, personal health records are commonly encrypted and outsourced to the cloud. However, this method is limited in verifying the integrity of personal health records, and there is a problem with poor data availability because it is essential to use it in decryption. To solve this problem, this paper proposes a verifiable cloud-based personal health record management scheme using Redactable signature scheme and zero-knowledge proof. Verifiable cloud-based personal health record management scheme can be used to verify the integrity of the original document while preserving privacy by deleting sensitive information by using Redactable signature scheme, and to verify that the redacted document has not been deleted or modified except for the deleted part of the original document by using the zero-knowledge proof. In addition, it is designed to increase the availability of data than the existing management schemes by designing to recover deleted parts only when necessary through the Redact Recovery Authority. And we propose a verifiable cloud-based personal health record management model using the proposed scheme, and analysed its efficiency by implementing the proposed scheme.

The Method of Recovery for Deleted Record of Realm Database (Realm 데이터베이스의 삭제된 레코드 복구 기법)

  • Kim, Junki;Han, Jaehyeok;Choi, Jong-Hyun;Lee, Sangjin
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.28 no.3
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    • pp.625-633
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    • 2018
  • Realm is an open source database developed to replace SQLite, which is commonly used in mobile devices. The data stored in the database must be checked during the digital forensic analysis process for mobile devices because it can help to understand the behavior of the user and whether the mobile device is operating or not. In addition, since the user can intentionally use anti-forensic techniques such as deleting data stored in the database, research on how to recover deleted records is needed. In this paper, we propose a method to recover records that have not been overwritten after deletion based on the analysis of the structure and record and deletion process of the Realm database file.

Effects of the Genetic Polymorphisms on Urinary Excretion of 1-Hydroxypyrene and 2-Naphthol (일반인구에서 유전자 다형성이 요중 1-hydroxypyrene 및 2-naphthol의 배설량에 미치는 영향)

  • Hwang Moon-Young;Cho Byung-Mann;Moon Seong-Bae
    • Journal of Environmental Science International
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    • v.14 no.5
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    • pp.499-511
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    • 2005
  • This study was performed to determine the effects of genetic polymorphisms, such as glutathione S-transferase ${\mu}1(GSTM1)$, glutathione S-transferase ${\Theta}1\;(GSTM1)$, glutathione S-transferase ${\pi}l (GSTP1)$, aryl hydrocarbon N-acetyltransferase 2 (NAT2), cytochrome P450 2E1 (CYP2E1), cytochrome P450 1A1 (CYP1A1) on the concentrations of urinary 1-hydroxypyrene (1-OHP) and 2-naphthol in general population with no occupational exposure to polycyclic aromatic hydrocarbons (PAHs). Study subjects were 257 men who visited a health promotion center in Susan. A questionnaire was used to obtain detailed data about age, smoking, drinking, body fat mass, intake of fat etc. Urinary l-OHP and 2-naphthol concentration were analyzed by HPLC system with a fluorescence detector. A multiplex PCR method was used to identify the genotypes for GSTM1 and GSTT1. The polymorphisms of GSTP1, NAT2, CYP1A1 and CYP2E1 were determined by the polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method. Urinary 1-OHP concentration was higher in deleted genotype of GSTM1, increased as smoking and alcohol drinking increased. Urinary 2-naphthol concentration was also rely on the age and smoking. Neither genetic polymorphism nor drinking-related factors were significantly related to urinary 2-naphthol concentration. No significant relation was found between physical characteristics and concentrations of urinary PAHs metabolites in the subjects, but the geometric mean of urinary 1-OHP and 2-naphthol was higher in the group with higher value compared to median value. These data suggest that in general population occupationally not exposed to PAHs, urinary concentration of PAHs metabolites is influenced by smoking, alcohol drinking and deleted genotype of GSTM1 in 1-OHP and smoking in 2-naphthol.

Sanitization of Open-Source Based Deduplicated Filesystem (오픈 소스 중복 제거 파일시스템에서의 완전 삭제)

  • Cho, Hyeonwoong;Kim, SeulGi;Kwon, Taekyoung
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.26 no.5
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    • pp.1141-1149
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    • 2016
  • Deduplicated filesystem can reduce usage of storage. However, it be able to recover deleted block. We studied sanitization of deduplicated filesystem, LessFS which is based on FUSE(Filesystem in USErspace). First, we show a vulnerability recover deleted data in the deduplicated filesystem. We implement sanitization of deduplicated filesystem considering the part of fingerprint DB with data blocks. It takes 60~70 times compared to without sanitization. Which means access time to fingerprint DB and overhead derived from increase of number of chunk have a critical impact on sanitization time. But in case of more than 65,536 Byte of chunksize, it is faster than normal filesystem without deduplication.

Validity and Reliability for the Use of Program Outcome Indirect Measurement Tool in Korean Nursing Baccalaureate Education (간호교육 프로그램 학습성과 간접측정도구의 활용을 위한 신뢰도 및 타당도 검증)

  • Song, Mi Ok;Kim, Heeyoung
    • The Journal of the Korea Contents Association
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    • v.21 no.8
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    • pp.608-618
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    • 2021
  • The aim of this study was to verify the feasibility and reliability of the program outcome indirect measurement tool developed for nursing college students in Korean. 396 nursing students from 5 nursing colleges participated in this study, data were collected from November 22 to December 10, 2019. Data analysis was conducted using the IBM Statistics SPSS 21.0 and AMOS 21.0 programs to analyze item analysis, exploratory and confirmatory factor analysis. As a result of the item analysis, all 79 items were selected for factor analysis. In the exploratory factor analysis, five items that were loaded with other factors were deleted. The final factor loading range was from .37 to .86, and the cumulative explanatory variance for 12 factors was 71.71%. No items were deleted as a result of the confirmatory factor analysis, and the final scale was consisted of 74 items. The average score for scale was 3.78 and Cronbach' α was .98. The feasibility and reliability of the program outcome indirect measurement tool have been verified through this study. Therefore it can be used as a more standardized indirect measurement tool for nursing college students.

Schm Constructions within Optimality Theory

  • Yu, Sihyeon
    • Korean Journal of English Language and Linguistics
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    • v.2 no.3
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    • pp.431-469
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    • 2002
  • The main purpose of this paper is to present data about schm constructions in English and to examine them within the framework of Optimality Theory. American people sometimes reduplicate a word in deprecation using a prefix schm- or shm-, as in fancy-shmancy, and old-shmold. In these data, reduplicants surface as a copy of the whole word except the onset of the first syllable, which is replaced with schm. My data include some examples where the onset of the second syllable, not the first syllable, within the word reduplication is deleted and replaced with fixed segmentism schm, which seems to be infix rather than prefix. Above all, this study presents concrete evidence for the existence and function of ‘syllable’ and ‘foot’ known as prosodic categories by examining schm reduplication. Such extensions of schm-reduplcation also make predictions about types of outputs corresponding to their inputs.

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Development of Finite Element Tire Model for Vehicle Dynamics Analysis (차량동역학 해석용 타이어 유한요소 모델 개발)

  • Jung, Sung Pil;Lee, Tae Hee;Kim, Gi Whan;Yun, So Joong
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2014.10a
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    • pp.858-861
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    • 2014
  • This paper presents a simplified finite element tire model for vehicle dynamics analysis. The classical finite element tire model was too big to simulate dynamic properties of the tire. In the simplified model, number of nodes of the tire model was dramatically reduced, and thus its simulation time was several times less than the classical model. Bead, carcass, belt which have an important role to the dynamic characteristics of tire were replaced by simple axis symmetric membrane elements. Also the rebar element was deleted. The tire model has been verified by comparing vertical stiffness data of the simulation model to the test data.

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A Security-Enhanced Identity-Based Batch Provable Data Possession Scheme for Big Data Storage

  • Zhao, Jining;Xu, Chunxiang;Chen, Kefei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.9
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    • pp.4576-4598
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    • 2018
  • In big data age, flexible and affordable cloud storage service greatly enhances productivity for enterprises and individuals, but spontaneously has their outsourced data susceptible to integrity breaches. Provable Data Possession (PDP) as a critical technology, could enable data owners to efficiently verify cloud data integrity, without downloading entire copy. To address challenging integrity problem on multiple clouds for multiple owners, an identity-based batch PDP scheme was presented in ProvSec 2016, which attempted to eliminate public key certificate management issue and reduce computation overheads in a secure and batch method. In this paper, we firstly demonstrate this scheme is insecure so that any clouds who have outsourced data deleted or modified, could efficiently pass integrity verification, simply by utilizing two arbitrary block-tag pairs of one data owner. Specifically, malicious clouds are able to fabricate integrity proofs by 1) universally forging valid tags and 2) recovering data owners' private keys. Secondly, to enhance the security, we propose an improved scheme to withstand these attacks, and prove its security with CDH assumption under random oracle model. Finally, based on simulations and overheads analysis, our batch scheme demonstrates better efficiency compared to an identity based multi-cloud PDP with single owner effort.