• Title/Summary/Keyword: key recovery

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Temporary Metadata Journaling Scheme to Improve Performance and Stability of a FAT Compatible File System (FAT 파일 시스템의 호환성을 유지하며 성능과 안정성을 향상시키는 메타데이터 저널링 기법의 설계)

  • Hyun, Choul-Seung;Choi, Jong-Moo;Lee, Dong-Hee;Noh, Sam-H.
    • Journal of KIISE:Computer Systems and Theory
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    • v.36 no.3
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    • pp.191-198
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    • 2009
  • The FAT (File Allocation Table) compatible file system has been widely used in mobile devices and memory cards because of its data exchangeability among numerous platforms recognizing the FAT file system. By the way. modern embedded systems have tough demands for instant power failure recovery and superior performance for multimedia applications. The key issue is how to achieve the goals of superior write performance and instant booting capability while controlling compatibility issues. To achieve the goals while controlling compatibility issues. we devised a temporary meta-data journaling scheme for a FAT compatible file system. Benchmark results of the scheme implemented in a FAT compatible file system shows that it really improves write performance of the FAT file system by converting small random write for meta-data update to a large sequential write in journaling area. Also, it provides natural way to implement the instant booting capability. Nevertheless, the file system compatibility is temporarily compromised by the scheme because it stores updated meta-data in the temporary journaling area rather than to their original locations. However, the compatibility can be fully recovered at any time by journal-flushing that copies meta-data in journaling area to their original locations. Generally, the journal-flushing is done before un-mounting a memory card so that it can be used in other mobile devices which recognized FAT file system but not the temporary meta-data journaling scheme.

A study on the Introduction Plans of Forest Land Bank System (산지은행제도의 도입방안에 관한 연구)

  • Kim, Jong-ho;Kim, Won Kyung;Kwon, Soon-duk
    • Journal of Korean Society of Forest Science
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    • v.104 no.3
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    • pp.503-511
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    • 2015
  • The purpose of this study is to suggest the introduction plans of forest land bank system for effective forestry management as well as the livelihood stability support of aged forest landowners. It is expected that forest land bank system can contribute to solve forestry management problems caused by small and scattered forest lands, aging forest landowners, and the increase of absentee forest landowners. This study examined an existing related case of Farmland Bank system, and suggested basic directions, main functions, priority, and agency for forest land bank system. The goals of forest land bank system include activating private forest land management, improving forest management scale, and supporting stable forestry income. Based on the examination of this study, main projects of forest land bank involve forest land sale and lease consignment, forest land reverse mortgage, forest land scale improvement project, and forest business recovery support program. In addition, this study discussed potential problems and their solutions in introducing and operating the forest land bank system. This study can play a key role to determine a basic direction and to establish policies of the forest land management.

Environmental Impact Assessment on Dismantling·Crushing·Sorting Process for Recycling of Used Small Household Appliances (폐소형가전 재활용을 위한 해체·파쇄·선별 공정의 환경영향 분석)

  • Park, Eun Kyu;Park, Ki Hak;Choi, Woo Zin;Kim, Soo Kyung
    • Resources Recycling
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    • v.25 no.2
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    • pp.17-24
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    • 2016
  • This study aims at evaluating environmental impacts on recycling process of used small household appliances. The recycling process mainly consists of manual dismantling, crushing and various sorting processes to effectively recover valuable resources and to minimize environmental impact. In this study, life-cycle assessment (LCA) methodology is applied to analyze major environmental parameters such as GWP, ADP, POCP, EP, etc. One of the major impact categories on the weight basis in the recycling process is global warming (GWP) 57.1%, next to ADP 35.4% and POCP 4.8%, respectively. As a result of environmental impact on recovery of valuable resources/ton, the GWP of plastics for ABS is highest (33.7%) compared to ferrous metals (9.4%). The effects of environmental and economical benefit are also analyzed to compare with the amount of virgin materials to be recycled by recycled materials. In addition, recycled materials are also more economical in comparison to virgin materials due to the environmental avoiding effect by recycling. In conclusion, the key environmental issues related to the recycling of e-wastes are analyzed and therefore, the effective recycling process will contribute to mitigate global warming potential in the near future.

Effectiveness of Stretching Exercise in The Treatment of The Iliotibial Band Friction Syndrome (장경대 마찰 증후군의 치료에서 스트레칭 운동의 유용성)

  • Suh, Jeung-Tak;Hong, Seong-Hwak;Lee, Choon-Key
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.5 no.2
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    • pp.147-154
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    • 2006
  • Purpose: To analyze the effectiveness of the treatment with the stretching exercise in the patients with iliotibial band (ITB) friction syndrome. Materials and Methods: 22 patients with ITB friction syndrome were treated with the stretching exercise of the ITB. The criterion for determining the good result is more than 75% recovery according to the classification of success of treatment. We analyzed the differences of the duration of treatment at which the good result it achieved according to sincerity of the stretching exercise. The sincerity of the exercise is defined at performing more than 50% of the exercise that we prescribed. Results: Of 22 patients, there were good results in 19 cases (87%) within 8 weeks after the treatment. Except for 3 cases who did not achieved good results, the average duration of the treatment is 28.1 days. In patients with good results there was no statistical significance for the relationship between the duration of symptoms before diagnosis (average 25.6 days) and the duration of the treatment (average 28.1 days). In comparison with the group who performed the exercise sincerely and the group who did not, the average duration of the treatment if 23 days and 32.7 days respectively and there was significant difference between the two groups. Conclusion: The stretching exercise in ITB friction syndrome was helpful in reducing the duration of treatment.

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A Reliable Group Key Re-transmission Mechanism in Ad-hoc Environment (Ad-hoc 환경에서 신뢰적인 그룹 키 재전송 기법)

  • Hong, Suk-Hyung;Kim, Kyung-Min;Lee, Kwang-Kyum;Sin, Young-Tae
    • Proceedings of the Korean Information Science Society Conference
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    • 2006.10d
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    • pp.370-374
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    • 2006
  • Ad-hoc 환경의 응용은 재난구조나 회의실 또는 강의실에서의 정보 교환과 같은 그룹 통에서 이용된다. Ad-hoc 환경은 무선 채널을 이용하므로 상대적인 낮은 대역폭과 높은 오류 발생률을 가지게 된다. 따라서 Ad-hoc 네트워크에서는 신뢰적인 전송이 요구된다. 이동 노드는 상대적으로 낮은 성능과 에너지의 제한으로 인해 유선 환경과 같은 신뢰적인 전송 기법을 Ad-hoc 환경에 적용하기에는 문제가 발생한다. Ad-hoc 환경의 무선 채널이 가지는 보안적인 취약성과 높은 에러율을 극복하는 신뢰적인 그룹 키 전송을 위한 재전송 기법을 제안한다. 신뢰적인 트리 형성하기 위해 n차 트리 구조를 이용한다. 손실 감지를 위한 ACK 메시지를 이용하고 손실 복구를 위한 재전송 기법에 대해 연구를 한다. 제안한 신뢰적인 그룹 키 전송을 위한 재전송 기법은 트리의 깊이의 차수가 루트 관리 노드, 서브 관리 노드와 로컬 멤버 노드로 구성되기 때문에 손실 감지와 손실 복구에 대한 연산의 오버헤드가 적다. 루트 관리 노드는 멤버 노드로부터 받은 개인키 정보를 이용하여 그룹 키를 생성하고 그룹 키 부분 정보를 서브 관리 노드에게 전송하고 서브 관리 노드에 대한 신뢰성을 책임진다. 서브 관리 노드는 루트 관리 노드로부터 받은 그룹 키 부분 정보를 로컬 멤버 노드에게 전송하고 로컬 멤버 노드에 대한 신뢰성을 책임진다. 루트 관리 노드와 서브 관리 노드를 관리 노드라 한다. 관리 노드가 신뢰적인 전송을 위해 관리하는 멤버 노드는 전체 그룹에 독립적으로 유지 가능하므로 확장성 및 효율성이 좋다. 관리 노드는 동적인 그룹에 따른 타이머를 설정함으로써 손실 감지에 대한 시간을 줄임으로써 효율적인 손실 감지 및 손실 복구를 한다. 임계값 설정으로 인한 중복 수신에 대한 오버헤드를 줄일 수 있다.신뢰성을 향상 시킬 수 있는 Load Balancing System을 제안한다.할 때 가장 효과적인 라우팅 프로토콜이라고 할 수 있다.iRNA 상의 의존관계를 분석할 수 있었다.수안보 등 지역에서 나타난다 이러한 이상대 주변에는 대개 온천이 발달되어 있었거나 새로 개발되어 있는 곳이다. 온천에 이용하고 있는 시추공의 자료는 배제하였으나 온천이응으로 직접적으로 영향을 받지 않은 시추공의 자료는 사용하였다 이러한 온천 주변 지역이라 하더라도 실제는 온천의 pumping 으로 인한 대류현상으로 주변 일대의 온도를 올려놓았기 때문에 비교적 높은 지열류량 값을 보인다. 한편 한반도 남동부 일대는 이번 추가된 자료에 의해 새로운 지열류량 분포 변화가 나타났다 강원 북부 오색온천지역 부근에서 높은 지열류량 분포를 보이며 또한 우리나라 대단층 중의 하나인 양산단층과 같은 방향으로 발달한 밀양단층, 모량단층, 동래단층 등 주변부로 NNE-SSW 방향의 지열류량 이상대가 발달한다. 이것으로 볼 때 지열류량은 지질구조와 무관하지 않음을 파악할 수 있다. 특히 이러한 단층대 주변은 지열수의 순환이 깊은 심도까지 가능하므로 이러한 대류현상으로 지표부근까지 높은 지온 전달이 되어 나타나는 것으로 판단된다.의 안정된 방사성표지효율을 보였다. $^{99m}Tc$-transferrin을 이용한 감염영상을 성공적으로 얻을 수 있었으며, $^{67}Ga$-citrate 영상과 비교하여 더 빠른 시간 안에 우수한 영상을 얻을 수 있었다. 그러므로 $^{99m}Tc$-transierrin이 감염 병소의 영상진단에 사용될 수 있을 것으로 기대된다.리를 정량화 하였다. 특히 선조체에서의 도파민 유리에 의한 수용체 결합능의 감소는 흡연에 의한 혈중 니코틴의 축

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Descriptive Study on the Development of Educational Program for Mothers with Children who have had Open Heart Surgery in Congenital Heart Disease (개심술을 받은 심기형 환아모의 교육프로그램 개발을 위한 조사연구)

  • Lee, Kun-Ja;Jo, Hyun-Sook
    • The Korean Journal of Rehabilitation Nursing
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    • v.4 no.1
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    • pp.73-83
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    • 2001
  • The aims of this study were to identify the mothers educational needs when they have children who have had open heart surgery in congenital heart disease, to identify the children's characteristics with this problem, and also to provide the basic information on the development of the educational program for the mothers. The subjects of the study were 101 mothers of children and their children hospitalized with congenital heart disease in pediatric wards of G. University Hospital in Inchon and S. Hospital in Puch on from June to November 2000. The study used a Likert-type questionnaire with 39 questions which was based on a previous questionnaire developed by Lee Mi-ryun(1989) for adult open heart surgery patients. The reliability of the questionnaire was Cronbach' ${\alpha}$=.9375. The data were collected directly from mothers of the patients in wards. The t-test, ANOVA was adopted for the data analysis. The key results of the study are as follows : 1) The average age of the children was 32.90 months. The majority of the children are male and weighted 3.0-3.5Kg at birth. Most of the children had VSD(29.7%), and 10.9% of children had a family history of heart disease. 2) An average score of 4.62 out of a maximum of 5.00 was recorded for the educational needs of the children's mother. The highest score of 4.69 was for home care after discharge followed by a score of 4.67 for diagnosis and prognosis on congenital heart disease. And pre-post operation care scored 4.51. The mean scores of single-question items of educational need were, in order, 4.81 for immunization after operation, 4.80 for recovery process, and 4.77 for prognosis of the disease. The score of 4.18 for measurement of intake and output was the lowest. 3) The analysis on the children's mothers educational needs by social-demographic characteristics such as sex, age of patient and mother, economical status, educational status, number of child, hospitalization times, and hospitalization cause showed no significant difference statistically, but there was a significant difference between mothers with jobs and with out jobs.

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Optimization and characterization of biodiesel produced from vegetable oil

  • Mustapha, Amina T.;Abdulkareem, Saka A.;Jimoh, Abdulfatai;Agbajelola, David O.;Okafor, Joseph O.
    • Advances in Energy Research
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    • v.1 no.2
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    • pp.147-163
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    • 2013
  • The world faces several issues of energy crisis and environmental deterioration due to over-dependence on single source of which is fossil fuel. Though, fuel is needed as ingredients for industrial development and growth of any country, however the fossil fuel which is a major source of energy for this purpose has always been terrifying thus the need for alternative and renewable energy sources. The search for alternative energy sources resulted into the acceptance of a biofuel as a reliable alternative energy source. This work presents the study of optimization of process of transesterification of vegetable oil to biodiesel using NaOH as catalyst. A $2^4$ factorial design method was employed to investigate the influence of ratio of oil to methanol, temperature, NaOH concentration, and transesterification time on the yield of biodiesel from vegetable oil. Low and high levels of the key factors considered were 4:1 and 6:1 mole ratio, 30 and $60^{\circ}C$ temperatures, 0.5 and 1.0 wt% catalyst concentration, and 30 and 60 min reaction time. Results obtained revealed that oil to methanol molar ratio of 6:1, tranesetrification temperature of $60^{\circ}C$, catalyst concentration of 1.0wt % and reaction time of 30 min are the best operating conditions for the optimum yield of biofuel from vegetable oil, with optimum yield of 95.8%. Results obtained on the characterizzation of the produced biodiesel indicate that the specific gravity, cloud point, flash point, sulphur content, viscosity, diesel index, centane number, acid value, free glycerine, total glycerine and total recovery are 0.8899, 4, 13, 0.0087%, 4.83, 25, 54.6. 0.228mgKOH/g, 0.018, 0.23% and 96% respectively. Results also indicate that the qualities of the biodiesel tested for are in conformity with the set standard. A model equation was developed based on the results obtained using a statistical tool. Analysis of variance (ANOVA) of data shows that mole ratio of ground nut oil to methanol and transesterification time have the most pronounced effect on the biodiesel yield with contributions of 55.06% and 9.22% respectively. It can be inferred from the results various conducted that vegetable oil locally produced from groundnut oil can be utilized as a feedstock for biodiesel production.

A Study on Cryptography Scheme and Secure Protocol for Safety Secure Scheme Construction in 13.56Mhz RFID (13.56Mhz RFID 환경에서 안전한 보안 스킴 구축을 위한 암호 스킴 및 보안 프로토콜 연구)

  • Kang, Jung-Ho;Kim, Hyung-Joo;Lee, Jae-Sik;Park, Jae-Pyo;Jun, Moon-Seog
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.3
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    • pp.1393-1401
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    • 2013
  • What is RFID Microchip tag attached to an object, the reader recognizes technology collectively, through communication with the server to authenticate the object. A variety of RFID tags, 13.56Mhz bandwidth RFID card, ISO/IEC 14443 standards based on NXP's Mifare tag occupies 72.5% of the world market. Of the Mifare tags, low cost tag Mifare Classic tag provided in accordance with the limited hardware-based security operations, protocol leaked by a variety of attacks and key recovery vulnerability exists. Therefore, in this paper, Cryptography Scheme and Secure Protocol for Safety Secure Scheme Construction in 13.56Mhz RFID have been designed. The proposed security scheme that KS generated by various fixed values and non-fixed value, S-Box operated, values crossed between LFSR and S-Box is fully satisfied spoofing, replay attacks, such as vulnerability of existing security and general RFID secure requirement. Also, It is designed by considering the limited hardware computational capabilities and existing security schemes, so it could be suit to Mifare Classic now.

An Efficient Congestion Control Mechanism for Tree-based Many-to-many Reliable Multicast (트리 기반의 다대다 신뢰적 멀티캐스트를 위한 효율적인 혼잡 제어 기법)

  • 유제영;강경란;이동만
    • Journal of KIISE:Information Networking
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    • v.30 no.5
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    • pp.656-667
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    • 2003
  • Congestion control is a key task in reliable multicast along with error control. However, existing tree-based congestion control schemes such as MTCP and TRAMCC are designed for one-to-many reliable multicast and have some drawbacks when they are used for many-to-many reliable multicast. We propose an efficient congestion control mechanism, TMRCC, for tree-based many-to-many reliable multicast protocols. The proposed scheme is based on the congestion windowing mechanism and a rate controller is used in addition. The feedback for error recovery is exploited for congestion control as well to minimize the overhead at the receivers. The ACK timer and the NACK timers are set dynamically reflecting the network condition changes. The rate regulation algorithm in the proposed scheme is designed to help the flows sharing the same link to achieve the fair share quickly The performance of the proposed scheme is evaluated using ns-2. The simulation results show that the proposed scheme outperforms TRAMCC in terms of intra- session fairness and shows good level of responsiveness, TCP-friendliness, and scalability. In addition, we implemented the proposed scheme by integrating with GAM that is one of many-to-many reliable multicast protocols and evaluated the performance in a laboratory-wide testbed.

Inhibition of endoplasmic reticulum stress in high-fat-diet-induced obese C57BL/6 mice: Efficacy of a novel extract from mulberry (Morus alba) leaves fermented with Cordyceps militaris

  • Lee, Mi Rim;Bae, Su Ji;Kim, Ji Eun;Song, Bo Ram;Choi, Jun Young;Park, Jin Ju;Park, Ji Won;Kang, Mi Ju;Choi, Hyeon Jun;Choi, Young Whan;Kim, Kyung Mi;Hwang, Dae Youn
    • Laboraroty Animal Research
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    • v.34 no.4
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    • pp.288-294
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    • 2018
  • A few clues about correlation between endoplasmic reticulum (ER) stress and mulberry (Morus alba) leaves were investigated in only the experimental autoimmune myocarditis and streptozotocin-induced diabetes. To investigate whether a novel extract of mulberry leaves fermented with Cordyceps militaris (EMfC) could suppress ER in fatty liver, alterations in the key parameters for ER stress response were measured in high fat diet (HFD)-induced obese C57L/6 mice treated with EMfC for 12 weeks. The area of adipocytes in the liver section were significantly decreased in the HFD+EMfC treated group as compared to the HFD+Vehicle treated group, while their level was higher in HFD+Vehicle treated group than No treated group. The level of the eukaryotic initiation factor 2 alpha ($eIF2{\alpha}$) and inositol-requiring enzyme 1 beta ($IRE1{\alpha}$) phosphorylation and CCAAT-enhancer-binding protein homologous protein (CHOP) expression were remarkably enhanced in the HFD+Vehicle treated group. However, their levels were restored in the HFD+EMfC treated group, although some differences were detected in the decrease rate. Similar recovery was observed on the ER stress-induced apoptosis. The level of Caspase-3, Bcl-2 and Bax were decreased in the HFD+EMfC and HFD+orlistat (OT) treated group compared to the HFD+Vehicle treated group. The results of the present study therefore provide first evidence that EMfC with the anti-obesity effects can be suppressed ER stress and ER stress-induced apoptosis in the hepatic steatosis of HFD-induced obesity model.