• 제목/요약/키워드: Compress

검색결과 474건 처리시간 0.031초

PoW-BC: A PoW Consensus Protocol Based on Block Compression

  • Yu, Bin;Li, Xiaofeng;Zhao, He
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제15권4호
    • /
    • pp.1389-1408
    • /
    • 2021
  • Proof-of-Work (PoW) is the first and still most common consensus protocol in blockchain. But it is costly and energy intensive, aiming at addressing these problems, we propose a consensus algorithm named Proof-of-Work-and-Block-Compression (PoW-BC). PoW-BC is an improvement of PoW to compress blocks and adjust consensus parameters. The algorithm is designed to encourage the reduction of block size, which improves transmission efficiency and reduces disk space for storing blocks. The transaction optimization model and block compression model are proposed to compress block data with a smaller compression ratio and less compression/ decompression duration. Block compression ratio is used to adjust mining difficulty and transaction count of PoW-BC consensus protocol according to the consensus parameters adjustment model. Through experiment and analysis, it shows that PoW-BC improves transaction throughput, and reduces block interval and energy consumption.

유사 비디오 시퀀스 기반의 라이트필드 영상 부호화를 위한 움직임 탐색 영역 제한 (Limiting Motion Search Range for the Pseudo Video Sequence-based Light Field Image Coding)

  • 임종훈;;;전병우
    • 한국방송∙미디어공학회:학술대회논문집
    • /
    • 한국방송∙미디어공학회 2022년도 하계학술대회
    • /
    • pp.182-183
    • /
    • 2022
  • The large data volume of light field (LF) image has motivated much research on how to compress the data volume more efficiently. One of the approaches is to compress LF images after representing them in the form of pseudo video sequence. In this way, the pseudo temporal redundancy between views can be exploited by motion estimation and compensation. Based on our observation that images obtained by LF cameras have small range of disparity values between adjacent views, we propose to limit the motion search range to reduce the time complexity of motion estimation. Our experimental results show that a smaller motion search range reduces the encoding time while not affecting the bitrate of H.266/VVC much.

  • PDF

반도체 공정의 생산성 향상을 위한 실시간 대용량 데이터의 효율적인 저장 기법 (An Efficient Storing Scheme of Real-time Large Data to improve Semiconductor Process Productivities)

  • 정원일;김환구
    • 한국산학기술학회논문지
    • /
    • 제10권11호
    • /
    • pp.3207-3212
    • /
    • 2009
  • 반도체 산업이 발전함에 따라 생산 효율을 높이기 위해 무인 자동 생산 공정이 요구되고 있다. 이러한 무인자동화 생산 관리 시스템은 생산성 향상을 위해 생산 공정에서 발생하는 대량의 실시간 데이터 분석 및 관리를 필요로 한다. 따라서 실시간으로 발생하는 대용량 데이터를 저장하기 위한 저장 관리 시스템이 요구된다. 기존의 저장 관리 시스템으로 오라클, MY-SQL, MS-SQL 등의 디스크 기반 DBMS가 있다. 하지만 기존의 디스크 기반 DBMS는 반도체 장비로부터 실시간으로 발생하는 대용량 데이터 처리에 한계가 있다. 본 논문에서는 대용량 데이터를 저비용으로 실시간 저장하기 위해 블록 단위 삽입 트랜잭션을 이용한 압축-합병 저장 기법을 제안한다. 제안 기법은 블록 단위 트랜잭션을 이용하여 실시간 데이터를 빠르게 저장하며 데이터를 압축하고 압축된 데이터를 합병하여 저장하기 때문에 보다 적은 디스크 공간을 사용하여 저장할 수 있다. 따라서 반도체 공정에서 빠르게 발생하는 대용량 데이터를 기존 DBMS보다 빠르게 저장이 가능하고 저장 공간 비용을 감소시킨다.

패치 영상의 효율적 압축을 위한 전처리 방법 (Preprocessing Method for Efficient Compression of Patch-based Image)

  • 이신욱;이선영;장은영;허남호;장의선
    • 방송공학회논문지
    • /
    • 제13권1호
    • /
    • pp.109-118
    • /
    • 2008
  • 텍스처 영상 압축은 JPEG과 같은 영상 압축 표준을 사용한다. 일반 텍스처 영상에는 JPEG으로도 좋은 압축 성능을 내지만 패치 텍스처 영상은 이러한 영상 압축 기술로 압축했을 때 좋은 압축 성능을 보이지 못하였다. 이를 보완하고 압축 성능을 높이기 위해 기존의 패치 텍스처 영상에 주변 화소간에 색차를 줄이기 위한 전처리 기술을 소개하고, 제안된 기술과 JPEG 압축을 순서대로 적용하였을 때 압축 성능이 23%에서 45%까지 향상됨을 보이고자 한다.

냉적용 방법에 따른 심부 및 피부온도변화 (Differences in Body Temperatures according to Three Methods of cold Application)

  • 임난영;김진경
    • 대한간호학회지
    • /
    • 제23권2호
    • /
    • pp.157-169
    • /
    • 1993
  • The most effective modality for cold application and the length of the application have not been determined despite many studies about the use of cold. A quasi-experimental study was conducted to examine the most effective modality among three methods of cold application, the most effective length of time for the application and the continuing effect after each type of cold application. Thirty adult patients admitted to medical and neurosurgical unit and with high fever (above 38.2 ℃) were assigned randomly to each of three cold ap-plication methods : (a) ice bag: (b) cold compress; and (c) tepid water sponge bath. Each method was applied to the whole anterior surface except the face and neck with the patient in the supine pos-ition. Rectal temperatures and skin temperatures (mid chest, upper arm, thigh and leg) were measured be-fore each application and every 10 minutes during ,each application for a period of 60 minutes. They were also measured every 10 minutes for 30 minutes after each cold application was finished. The experiments were carried out from Dec. 22. 1992 through Feb. 26, 1993. The data were analysed using means, ANCOVA Sheffe test and Pearson's Correlation Coefficient. The results of this study are as follows : 1. There were no significant differences among the three cold application methods in the reduction of body temperature, 2. Among the ice bag, cold compress and tepid water sponge bath groups, the ice bag proved to be the most effective method for lowering skin temperature while the cold compress was least effective. 3. Both rectal and skin temperature continued to decrease during the 60 minutes of cold application, but the hunting phenomena was not observed at any of the cold application sites. 4. There were no significant correlations between mean rectal and skin temperatures. 5. Skin temperatures according to the cold application sites decreased to a range of 3.46℃ to 5.20℃ (mid chest), a range of 4.48℃ 4.96℃ (upper arm), a range of 3.86℃ to 5.05℃ (thigh), and a range of 5.42℃ -7.12℃ (leg ). 6. In continuing effect after the cold applications were finished, rectal temperatures according to ice bag, cold compress and tepid sponge bath decreased to 0.29℃, 0.23℃ and 0.09℃ respectively, while the mean skin temperatures increased to 2.39℃ , 2.04℃ and 2.22℃ respectively. In this experiment the ice bag was the most effective modality for lowering skin temperature. when-ever cold is applied for systemic effect, the continuing effect of cold should be considered. The determination of the most effective length of time for cold application needs further study.

  • PDF

Lossless VQ Indices Compression Based on the High Correlation of Adjacent Image Blocks

  • Wang, Zhi-Hui;Yang, Hai-Rui;Chang, Chin-Chen;Horng, Gwoboa;Huang, Ying-Hsuan
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제8권8호
    • /
    • pp.2913-2929
    • /
    • 2014
  • Traditional vector quantization (VQ) schemes encode image blocks as VQ indices, in which there is significant similarity between the image block and the codeword of the VQ index. Thus, the method can compress an image and maintain good image quality. This paper proposes a novel lossless VQ indices compression algorithm to further compress the VQ index table. Our scheme exploits the high correlation of adjacent image blocks to search for the same VQ index with the current encoding index from the neighboring indices. To increase compression efficiency, codewords in the codebook are sorted according to the degree of similarity of adjacent VQ indices to generate a state codebook to find the same index with the current encoding index. Note that the repetition indices both on the search path and in the state codebooks are excluded to increase the possibility for matching the current encoding index. Experimental results illustrated the superiority of our scheme over other compression schemes in the index domain.

황토 콘크리트의 배합조건에 따른 강도성상 및 내구성 (Characteristics of Strength and Durability of Hwangto-Concrete according to its Mixing Condition)

  • 황혜주;노태학;김진일
    • KIEAE Journal
    • /
    • 제8권5호
    • /
    • pp.55-60
    • /
    • 2008
  • The purpose of this study is to increase the use of Hwangto and examine the strength according to what it is compounded with. Hwangto-concrete containing Hwanto without cement nor organic chemical products were compared to the traditional cement concrete through some durability experiments. We expect to gain more knowledge on the potentials of Hwangto-concrete as an architectural source. 1) As Hwangto binder amount rises, the value of slump increases too. The reason is that the increase of the quantity of cement causes the increase of the amount of material and the decrease of the amount of aggregate. 2) When the mixed component into Hwangto-concrete remains at 2%, the compress strength is generally dispersed high along the per unit fission, in case the amount of which is at $400(g/m^3)$. The highest compress strength is 39MPa. It means that it can be applied to common structures and we need to conduct a basic property test to ensure the strength and fluidness. 3) Hwangto-concrete is expected to be highly used in the ocean structure and chemical industry because it has better resistance to sulfuric acid and to hydrochloric acid than the cement-concrete has. The result of this study is as follows. It is expected that Hwangto-concrete will be widely applied and further research on its durability and tests for its basic substantial characteristics based on future component added to it.

위진시대(魏晋時代)의 외치요법(外治療法)에 관한 연구 (A Study of External Treatment History in Wei(魏) Dynasty and Jin(晋) Dynasty)

  • 문우상;김은하;이병욱
    • 대한한의학원전학회지
    • /
    • 제18권3호통권30호
    • /
    • pp.70-80
    • /
    • 2005
  • 1) Objective External treatments have various curative effects. So it had been used to cure various patients. But, it has a limited sphere of application in the present South Korea. Therefore we would like to bring out its sphere of application and detailed method in the oriental medicine classics. 2) Conclusions From long time ago people have used external treatment to cure various disease. According to the ${\lceil}Nei-Jing{\rfloor}$, hot compress therapy, fumigation therapy and bathing therapy had been used to cure blockage syndrome, muscle disease, carbuncle and cellulitis. Thereafter, a sphere of external treatment had gradually enlarged. (1) After all its sphere had included dermatologic, psychologic, internal, ophthalmic, otolaryngologic, obstetrics, gynecologic, pediatric and surgical diseases. (2) External treatment methods have contained hot compress therapy, fumigation therapy, bathing therapy, application therapy, medication bag therapy, medication plug therapy, medication massotherapy, aroma therapy and so on. (3) Medication types of external treatment have contained ointment, juice, infusion, powder, suppository and so on.

  • PDF

Bag-Valve-Mask의 사용방법에 따른 일회호흡량과 평균기도압의 변화 연구 (Differentiation of tidal volume & mean airway pressure with different Bag-Valve-Mask compression depth and compression rate)

  • 조승묵;정형근
    • 한국응급구조학회지
    • /
    • 제16권2호
    • /
    • pp.67-74
    • /
    • 2012
  • Purpose : The purpose of this study is to get basal user guidelines of safer bag-valve-mask application on patient with normal pulmonary patho-physiologic condition. Methods : This study was accomplished by pre-qualified 25 EMS junior grade students. Participants were instructed randomly compress bag to one-third, half and total and also with differesnt compression speed. Resultant tidal volumes and mean airway pressures obtained in RespiTrainer were analysed in relation to the each compression depth and rate. Results : Demographic difference does not affect tidal volume with any compression depth and rate change. Increasing compression depth is correlated with tidal volume increasement at any compression rate and also with mean airway pressure. If the compression depth is same, compression rate change did not affect significantly the resultant tidal volume or mean airway pressure. Conclusion : Hand size, Experience, BMI dose not affect tidal volume. Compress the 1600 ml bag half to total amount is safe way to offer sufficient tidal volume without risky high airway pressure delivery to patient airway who with normal lung patho-physiologic condition.