• 제목/요약/키워드: Free Block Management

검색결과 21건 처리시간 0.026초

실시간 재생 서비스를 위한 비트맵 방식의 연속 블록 할당 기법 (A Bitmap-based Continuous Block Allocation Scheme for Realtime Retrieval Service)

  • 박기현
    • 한국멀티미디어학회논문지
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    • 제5권3호
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    • pp.316-322
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    • 2002
  • 본 논문에서는 파일 데이터의 실시간 재생 서비스를 제공하기 위한 UNIX파일 시스템의 연속 블록 할당에 대하여 다루고 있다. 설계된 블록 할당 방식은 사용자가 저장 데이터와 함께 지정한 소비 전송율을 지원할 수 있도록 적절한 디스크 위치에 데이터를 배치하여 실시간 재생 서비스를 지원할 수 있도록 하고 있다. 이를 위하여 데이터 전송율에 영향을 미치는 요소 중에서 가변적인 특성인 연속 블록 수와 저장 데이터들의 실린더 간격과의 관계를 분석하여 특정 실린더 간격 별로 연속 블록을 저장하는 방식을 채택하였다. UNIX시스템의 블록 할당 방식은 임의의 실린더 위치에서 연속 블록을 찾는 것이 비효율적 이기 때문에 새로운 형태의 비트맵 방식의 유휴 블록 기법을 사용하였다. 비트맵 방식의 블록 관리 기법은 파일 시스템 블록들을 비트 단위로 사용/비사용 여부를 표시하여 임의의 실린더 위치에 존재하는 블록이 사용 가능한지를 효율적으로 검색할 수 있도록 하였다.

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어머니-영아간 전통놀이, 자유놀이, 블록놀이의 언어적 상호작용 비교 (Mother-Toddler Verbal Interaction Comparative Study in Traditional, Free and Block Play)

  • 이행숙;한유진
    • 가정과삶의질연구
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    • 제27권1호
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    • pp.181-196
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    • 2009
  • This study compared mother-toddler verbal interaction by play type (traditional play, free play, block play), and child's sex and age. Subjects were 10 boys and 10 girls ranging in age from 25- to 36-months and their mothers. An observer videotaped the children and their mothers at play in their homes. Results showed that (1) Mothers attempted more positive verbal interaction in traditional than in block play. (2) Mothers expressed more positive emotion in free than in traditional and block play. (3) Mothers more answer 'reflection' in traditional than in free play (4) Toddlers attempted more positive verbal interaction in block than in traditional and free play. (5) Toddler's positive emotion express was not distinguished by play type or by child's sex or age. (6) From 31- to 36-months's boys expressed more play situation than from 25- to 30-months' girls. This study provides groundwork for mother-toddler traditional play programs with potential for improving positive expression of emotion and language development.

Comparison of Pain Management Strategies to Reduce Opioid Use Postoperatively in Free Flap Breast Reconstruction: Pain Catheter versus Nerve Block in Addition to Refinements in the Oral Pain Management Regime

  • Andrea B. Stefansdottir;Luis Vieira;Arni Johnsen;Daniel Isacson;Andres Rodriguez;Maria Mani
    • Archives of Plastic Surgery
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    • 제51권2호
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    • pp.156-162
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    • 2024
  • Background Perioperative management in autologous breast reconstruction has gained focus in recent years. This study compares two pain management protocols in patients undergoing abdominal-based free flap breast reconstruction: a past protocol (PP) and a current protocol (CP)-both intended to reduce opioid consumption postoperatively. The PP entails use of a pain catheter in the abdominal wound and the CP consists of an intraoperative nerve block in addition to refinements in the oral pain management. We hypothesize that the CP reduces opioid consumption compared to PP. Methods From December 2017 to January 2020, 102 patients underwent breast reconstruction with an abdominal-based free flap. Two postoperative pain management strategies were used during the period; from December 2017 to September 2018, the PP was used which entailed the use of a pain catheter with ropivacaine applied in the abdominal wound with continuous distribution postoperatively in addition to paracetamol orally and oxycodone orally pro re nata (PRN). From October 2018 to January 2020, the CP was used. This protocol included a combination of intraoperative subfascial nerve block and a postoperative oral pain management regime that consisted of paracetamol, celecoxib, and gabapentin as well as oxycodone PRN. Results The CP group (n = 63) had lower opioid consumption compared to the PP group (n = 39) when examining all aspects of opioid consumption, including daily opioid usage in morphine milligram equivalents and total opioid usage during the stay (p < 0.001). The CP group had shorter length of hospital stay (LOS). Conclusion Introduction of the CP reduced opioid use and LOS was shorter.

블록 반복측정을 이용한 품질통계 모형의 유형화 (Model Classification of Quality Statistics Using Block Repeated Measures)

  • 최성운
    • 대한안전경영과학회지
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    • 제9권3호
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    • pp.165-171
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    • 2007
  • Dependent models in quality statistics are classified as serially autocorrelated model, multivariate model and dependent sample model. Dependent sample model is most efficient in time and cost to obtain samples among the above models. This paper proposes to implement parametric and nonparametric models into production system depended on demand pattern. Nonparametric models have distribution free and asymptotic distribution free techniques. Quality statistical models are classified into two categories ; the number of dependent sample and the type of data. The type of data consists of nominal, ordinal, interval and ratio data. The number of dependent sample divides into 2 samples and more than 3 samples.

후두신경통 환자에서 시행한 경피적 제2경추신경절 절제술 -증례 보고- (Percutaneous C2 Ganglionotomy in the Management of Occipital Neuralgia -A case report-)

  • 임소영;김수관;신근만;홍순용;최영룡
    • The Korean Journal of Pain
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    • 제9권1호
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    • pp.200-205
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    • 1996
  • Radiofrequency thermocoagulation(RF) techniques are safe and effective methods as compared to neurodestructive procedure. Other advantages are: ability to perform RF lesions under local or sedative anesthesia, rapid recovery period, low incidence of morbidity and mortality, ability to repeat RF lesions, and leaves no significant scarring. We performed C2 ganglionotomy by RF lesion generator on a patient, suffering post-traumatic occipital neuralgia, as the patient did not respond to conservative therapies such as: trigger point injection, TENS, cryotherapy and stretch, occipital nerve block, C2 ganglion block. Prognostic nerve block was performed usng local anesthetics. Excellent effect was conformed before C2 ganglionotomy. This procedure was performed under fluoroscopy. Type RCK-2A Rosomoff Cordotomy kit was used to stabilize the head and neck. Postoperatively, the patient was free of occipital pain and head motions no longer triggered pain. To date, the patient remains symptom free except for some cervical discomfort.

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A File System for Large-scale NAND Flash Memory Based Storage System

  • Son, Sunghoon
    • 한국컴퓨터정보학회논문지
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    • 제22권9호
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    • pp.1-8
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    • 2017
  • In this paper, we propose a file system for flash memory which remedies shortcomings of existing flash memory file systems. Besides supporting large block size, the proposed file system reduces time in initializing file system significantly by adopting logical address comprised of erase block number and bitmap for pages in the block to find a page. The file system is suitable for embedded systems with limited main memory since it has small in-memory data structures. It also provides efficient management of obsolete blocks and free blocks, which contribute to the reduction of file update time. Finally the proposed file system can easily configure the maximum file size and file system size limits, which results in portability to emerging larger flash memories. By conducting performance evaluation studies, we show that the proposed file system can contribute to the performance improvement of embedded systems.

항문 이급후중의 치료에 있어 외톨이 신경절 차단 (Ganglion Impar Block in the Management of Rectal Tenesmoid Pain)

  • 김수관;안철수;조용노;임소영;신근만;홍순용;최영룡
    • The Korean Journal of Pain
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    • 제9권1호
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    • pp.226-228
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    • 1996
  • Rectal tenesmus is a persistent, painful and ineffectual sensation of straining at stool or opening of the bowels. The pain is usually spasmodic in nature and most commonly encountered in patients with carcinoma of the rectum or other pelvic organs. In 1988, Bristowand Foster reported that patients with severe spasmodic painful tenesmus were relieved with chemical sympathectomy. In 1990, Plancarte introduced block of Ganglion impar. This technique is proposed as an alternative means of managing localized perineal pain of sympathetic origin. Ganglion impar block was performed on a 54-year-old female patient when analgesic or psychotropic drugs failed to control the symptoms of post-traumatic severe spasmodic painful tenesmus. Postoperatively, patient was free of tenesmoid pain for only 7 days. We then performed neurotomy by RF lesion generator which provided complete pain relief.

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다양한 할당 정책을 지원하는 실시간 동적 메모리 할당 알고리즘 (A Real-time Dynamic Storage Allocation Algorithm Supporting Various Allocation Policies)

  • 정성무
    • 한국통신학회논문지
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    • 제25권10B호
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    • pp.1648-1664
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    • 2000
  • This paper proposes a real-time dynamic storage allocation algorithm QSHF(quick-segregated-half-fit) that provides various memory allocation policies. that manages a free block list per each word size for memory requests of small size good(segregated)-fit policy that manages a free list per proper range size for medium size requests and half-fit policy that manages a free list per proper range size for medium size requests and half-fit policy that manages a free list per each power of 2 size for large size requests. The proposed algorithm has the time complexit O(1) and makes us able to easily estimate the worst case execution time(WCET). This paper also suggests two algorithm that finds the proper free list for the requested memory size in predictable time and if the found list is empty then finds next available non-empty free list in fixed time. In order to confirm efficiency of the proposed algorithm we simulated the memory utilization of each memory allocation policy. The simulation result showed that each policy guarantees the constant WCET regardless of memory size but they have trade-off between memory utilization and list management overhead.

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MacOS에서 파일확장자 관리를 통한 랜섬웨어 탐지 및 차단 방법 (How to Detect and Block Ransomware with File Extension Management in MacOS)

  • 윤정무;류재철
    • 정보보호학회논문지
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    • 제27권2호
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    • pp.251-258
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    • 2017
  • 랜섬웨어를 비롯한 대부분의 악성코드들은 Windows 운영체제를 대상으로 제작된다. 점유율이 높은 운영체제를 목표로 삼아야 그만큼 피해가 더 커지기 때문이다. 하지만 최근 몇 년 전부터 MacOS의 운영체제의 점유율이 꾸준히 증가하고 있다. 사람들에게 점점 많이 사용되기 시작하면서 MacOS운영체제에서 동작하는 악성코드의 수도 점점 늘어나고 있는 상황이다. 랜섬웨어는 2015년부터 우리나라에 많이 알려지기 시작했으며 점차 피해사례도 증가하고 있다. 2016년 3월에 MacOS용 랜섬웨어가 발견되는 등 더 이상 MacOS도 랜섬웨어로부터 자유롭지 않은 상황이다. 앞으로 계속 발생 할 랜섬웨어에 대처하기 위해서 본 논문은 랜섬웨어를 탐지하기 위한 방법으로 랜섬웨어가 암호화 한 파일의 확장자를 변경하는 것을 이용하였다. 사용자에 의해 확장자가 변경되는 것과 랜섬웨어 프로세스에 의해 확장자가 변경되는 것을 구분함으로써 랜섬웨어 프로세스를 탐지하고 차단하는 방법을 연구했다.

플래시 메모리를 위한 페이지 비율 분석 기반의 적응적 가비지 컬렉션 정책 (Adaptive Garbage Collection Policy based on Analysis of Page Ratio for Flash Memory)

  • 이승환;이태훈;정기동
    • 한국정보과학회논문지:시스템및이론
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    • 제36권5호
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    • pp.422-428
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    • 2009
  • 플래시 메모리는 부피가 작고, 가볍고, 소비전력이 낮으며 입출력이 빨라 최근 소형기기의 저장 장치로 널리 사용이 되고 있다. 그러나 플래시 메모리는 지움 연산을 수반하는 가비지 컬렉션을 수행해야 한다. 지움 연산은 속도가 느리고, 각 블록마다 지움 연산 횟수가 제한이 있다. 따라서 본 논문에서는 지움 연산 횟수와 각 블록의 지움 횟수 편차를 줄이는데 초점을 맞춘 균등화 정책을 제안한다. 따라서 플래시 메모리의 페이지 사용률에 기반을 둔 두 가지 가비지 컬렉션 수행 모드를 정의하고 그리고 각 모드에 대해 다른 지움 비용을 계산하여 전체 지움 연산 횟수와 각 블록의 지움 횟수 편차를 최소화하는 가비지 컬렉션 기법을 제안한다. 추가로 가비지 컬렉션 연산 시간을 최소화하기 위해 그룹 관리 기법을 제안해 보다 빠른 수행 시간을 가질 수 있도록 한다. 실험 결과 제안하는 정책은 기존의 Greedy 와 CAT 기법의 장점들을 동시에 나타내었고, 지움 횟수 편차를 평균 85% 감소 시켰고 가비지 컬렉션 수행 시간을 최대 6% 단축 시켰다