• 제목/요약/키워드: Bloom

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Efficient Hybrid Transactional Memory Scheme using Near-optimal Retry Computation and Sophisticated Memory Management in Multi-core Environment

  • Jang, Yeon-Woo;Kang, Moon-Hwan;Chang, Jae-Woo
    • Journal of Information Processing Systems
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    • 제14권2호
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    • pp.499-509
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    • 2018
  • Recently, hybrid transactional memory (HyTM) has gained much interest from researchers because it combines the advantages of hardware transactional memory (HTM) and software transactional memory (STM). To provide the concurrency control of transactions, the existing HyTM-based studies use a bloom filter. However, they fail to overcome the typical false positive errors of a bloom filter. Though the existing studies use a global lock, the efficiency of global lock-based memory allocation is significantly low in multi-core environment. In this paper, we propose an efficient hybrid transactional memory scheme using near-optimal retry computation and sophisticated memory management in order to efficiently process transactions in multi-core environment. First, we propose a near-optimal retry computation algorithm that provides an efficient HTM configuration using machine learning algorithms, according to the characteristic of a given workload. Second, we provide an efficient concurrency control for transactions in different environments by using a sophisticated bloom filter. Third, we propose a memory management scheme being optimized for the CPU cache line, in order to provide a fast transaction processing. Finally, it is shown from our performance evaluation that our HyTM scheme achieves up to 2.5 times better performance by using the Stanford transactional applications for multi-processing (STAMP) benchmarks than the state-of-the-art algorithms.

OCEANOGRAPHIC EVENTS AT NORTHERN BORNEO AND THEIR RELATIONSHIP TO HARMFUL ALGAL BLOOMS

  • Knee, Tan Chun;Ishizaka, Joji;Ransi, Varis;Son, Tong Phuoc Hoang;Tripathy, Sarat Chandra;Siswanto, Eko
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.491-494
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    • 2006
  • The west coast of Northern Borneo is strongly influenced by Asian monsoon. Present research using the satellite ocean color (OC) remote sensing has identified some interesting oceanographic phenomena in this area that could be related to the harmful algal blooms (HAB). Occurrence of seasonal upwelling event was noticed off the northern tip of Borneo Island that could be related to the northeast monsoon wind. Harmful algal blooms by Pyrodinium bahamense var. compressum occurred since 1976. Subsequently, during December 2003, there was a report of new HAB by Cochlodinium polykrikoides in Northern Borneo. Analysis of OC images revealed that the Cochlodinium bloom had very high chlorophyll a signal and strong absorption characteristics. Results showed that the Baram River plume and upwelling at Northern Borneo were the source of nutrient for the Cochlodinium bloom in the offshore region. Ocean color images of 2004 showed that the bloom from Northern Borneo had crossed the Balabac Straits, reaching Palawan Island in Philippine. Due to the possibility of transboundary HAB problem, we propose a regional HAB monitoring network for an effective HAB management.

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부안 상록해수욕장의 사상 녹조류 금발대마디말(Cladophora vadorum) 대량발생과 영양염 농도 (Bloom of a Filamentous Green Alga Cladophora vadorum (Areschoug) Kützing and Nutrient Levels at Shangrok Beach, Buan, Korea)

  • 하동수;유현일;장수정;황은경
    • 한국수산과학회지
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    • 제49권2호
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    • pp.241-246
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    • 2016
  • A filamentous green alga Cladophora vadorum (Areschoug) Kützing, bloomed at Shangrok Beach, Buan, Republic of Korea, in September 2015. This alga is currently distributed worldwide. Concentrations of total nitrogen (TN), total phosphorus (TP), dissolved inorganic nitrogen (DIN), and dissolved inorganic phosphorus (DIP) were analyzed in the bloom area and compared to those of other areas in the vicinity. DIN and DIP concentrations were similar to those of other areas. However, TN and TP were as much as six and ten times higher than in other areas, respectively. As in other Cladophora species, the bloom of C. vadorum at Shangrok Beach in 2015 appears to have depended on the TP concentration in the seawater. This suggests that blooms in the area can be controlled by reducing TP.

댐 방류조건에 따른 저수지 유속과 수온 영향 (The Effect of Current and Temperature of a Reservoir by the Simulation of Dam Outflow)

  • 유순주;하성룡;정동일
    • 한국물환경학회지
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    • 제22권6호
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    • pp.1060-1067
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    • 2006
  • Water quality in the Daecheong reservoir has been deteriorated by algal bloom due to nutrient supply from the upstream of the Daecheong reservoir after heavy rainfall. Algal bloom is propagated from eutrophicated tributary into the main body of the reservoir according to the hydrological conditions. This study is aimed to estimate the water current and temperature effect by the simulation of dam spill flow control using water quality model, CE-QUAL-W2 in 2003. Water current was resulted in nutrient transport from upstream of main reservoir and nutrients were delivered up to downstream by fast water velocity. Algal blooms occurred in stagnate zone of reservoir downstream as the current of downstream was retarded according to dam outflow control. Consequently water balance in stagnate zone triggered a rise of water temperature in summer. It affected algal bloom in the embayment of the reservoir. The simulation result by outflow control scenarios showed that spill flow augmentation induced in water body instability of stagnate zone so that water temperature declined. It could be suggested that outflow control minimize algal bloom in the downstream in the flooding season as long as water elevation level is maintained properly.

A study on the algal growth-related water quality of the Sangsa lake

  • Kim, Jong-Min;Lee, Jong-Chun;Chang, Nam-Ik;Ryu, Seong-Ho;Shin, Dae-Yoon
    • 한국환경생물학회:학술대회논문집
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    • 한국환경생물학회 2004년도 학술대회
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    • pp.27-27
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    • 2004
  • We studied algal growth-related water quality of the Sangsa lake which is the drinking water reservoir for the south-eastern region of Jeonnam province. Peridinium cinctum and several diatomic algal species frequently caused water bloom throughout the lake from early spring to late autumn. With the heaviest predominance of Peridinium cintum in May 2003, COD was 22.7 mg/l in the surface layer. Highly turbid surface water of 15 NTU was also caused by Perdinium bloom. Cyanobacterial growth was effectively prohibited by dominant growth of Peridinium in the Sangsa lake, otherwise confronted with cyanobacterial bloom. Dense algal layer was confined in the upper several meters of the water column above the thermocline, which gives relatively algae-free water in deeper layer suitable for drinking source water supply. Upon collapse of thermocline, water quality of the surface layer was improved while deeper layer was deteriorated. This paper deals with some details of water quality changes with algal growth in the Sangsa lake past two years.

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대청호 유속에 따른 조류이동 영향 (The Relationship between Algae Transport and Current in the Daecheong Reservoir)

  • 유순주;황종연;채민희;김상용
    • 한국물환경학회지
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    • 제22권5호
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    • pp.887-894
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    • 2006
  • Water quality in the Daecheong reservoir has been deteriorated by algal bloom every year. Algal bloom is propagated from eutrophicated tributary into the main body of the reservoir during the wet season. Nutrients from diffuse sources trigger the propagation of the algal bloom. This study is aimed to analyze relationship between the water current by the simulation and algae transport from the main body in the Daecheong reservoir including tributary where algal bloom has occurred seriously every year. Water quality model CE-QUAL-W2 was applied to analyze water movement in draught season (2001) and flooding season (2003). The result of simulation corresponded with the observed water elevation level, 63~80 m and showed stratification of the Daecheong reservoir. In the draught season, as velocity and direction off low in the reservoir was estimated to affect algae transport including nutrient supply from small tributary, algal blooms occurred in the stagnate zone of middle stream of the reservoir. On the other hand, in the flooding season, it was resulted in nutrient transport from upstream of main reservoir and nutrients were delivered up to downstream by fast water velocity. In result, algal blooms occurred in stagnate zone of reservoir downstream as the current of downstream was retarded according to dam outflow control.

VANET에서 카운팅 블룸 필터를 사용한 효율적인 그룹 키 관리 기법 (An Efficient Group Key Management Scheme using Counting Bloom Filter in VANET)

  • 이수연;안효범
    • 융합보안논문지
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    • 제13권4호
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    • pp.47-52
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    • 2013
  • VANET(Vehicular Ad-hoc Network)은 원활한 교통 소통, 사고 방지 등 여러 가지 편리한 기능들을 제공하지만 그 기반을 애드혹 네트워크에 두고 있기 때문에 애드혹 망에서 발생하는 보안 문제를 가지고 있다. VANET에서 사용자의 프라이버시를 보호하기 위해 그룹 서명방식 등이 연구되어졌다. 그러나 그룹 간에 그룹 키 생성 단계 및 그룹 키 갱신단계에서 RSU(Road-Side Unit) 및 차량의 계산상 오버헤드가 발생한다. 본 논문에서는 효율적인 그룹 키 관리 기술을 제안한다. 즉, 그룹 키 생성 및 갱신 단계에서 CBF(Counting Bloom Filter)를 사용하므로 RSU 및 차량의 계산상 오버헤드를 감소시킨다. 또한, RSU와 차량에서 그룹 키를 자체적으로 갱신하여 관리하는 기법이다.

Bloom의 교육목표 분류에 기반한 치위생학 학습목표 분석 (Analysis of dental hygiene learning objectives based on Bloom's taxanomy)

  • 기지윤;장종화
    • 한국치위생학회지
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    • 제21권2호
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    • pp.193-201
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    • 2021
  • Objectives: We evaluated the learning objectives of dental hygiene courses based on Bloom's learning objectives, and analyze the degree of match with the dental hygienist's job for each detailed subject. Methods: The 5th edition of 'Dental hygiene and learning objectives' was analyzed by subject based on Bloom's cognitive domain classification from March 10 to April. In addition, the degree of match between the contents of the secondary job analysis of the dental hygienist and the learning objectives for each detailed subject were analyzed. Results: The total number of dental hygiene learning objectives was 2,975 (2,762 theory, 52 practice). Among the cognitive domains, the comprehension domain was the most common (79.8%), and the skill domain was very low (4.9%). In the job for each detailed subject of dental hygiene, the most frequently performed was 'dental prophylaxis and practice' with 103 subjects. Conclusions: Overall, dental hygiene learning objectives are mostly theory-oriented, so it is necessary to expand and improve in the direction related to the jobs that clinical dental hygienists perform in the field. In addition, it is necessary to continuously develop timely learning goals, and prepare active strategies for developing high-quality items.

An Efficient PSI-CA Protocol Under the Malicious Model

  • Jingjie Liu;Suzhen Cao;Caifen Wang;Chenxu Liu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제18권3호
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    • pp.720-737
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    • 2024
  • Private set intersection cardinality (PSI-CA) is a typical problem in the field of secure multi-party computation, which enables two parties calculate the cardinality of intersection securely without revealing any information about their sets. And it is suitable for private data protection scenarios where only the cardinality of the set intersection needs to be calculated. However, most of the currently available PSI-CA protocols only meet the security under the semi-honest model and can't resist the malicious behaviors of participants. To solve the problems above, by the application of the variant of Elgamal cryptography and Bloom filter, we propose an efficient PSI-CA protocol with high security. We also present two new operations on Bloom filter called IBF and BIBF, which could further enhance the safety of private data. Using zero-knowledge proof to ensure the safety under malicious adversary model. Moreover, in order to minimize the error in the results caused by the false positive problem, we use Garbled Bloom Filter and key-value pair packing creatively and present an improved PSI-CA protocol. Through experimental comparison with several existing representative protocols, our protocol runs with linear time complexity and more excellent characters, which is more suitable for practical application scenarios.

Bloom의 신교육 목표 분류학에 기초한 초등학교 3, 4학년 과학과 7차 교육과정과 2007 개정 과학과 교육과정의 목표체계 비교 (Comparison of Instructional Objectives of the 2007 Revised Elementary Science Curriculum with 7th Elementary Curriculum based on Bloom's Revised Taxonomy)

  • 위수민;김보경;조현준;손정주;오창호
    • 한국초등과학교육학회지:초등과학교육
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    • 제30권1호
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    • pp.10-21
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    • 2011
  • The purposes of this study were to classify the objectives in elementary science for the 2007 revised national curriculum in accordance with Bloom's Revised Taxonomy of Educational Objectives, and to compare the classified data of 2007 revised curriculum with 7th national curriculum from a view of creative objectives. For the purpose, the frame and manuel was developed to classify the objectives. In this study, elementary science instructional objectives of third- to forth-grade level were classified through the frame. The finding of this study revealed that the objectives, stated in elementary science for the 2007 revised national curriculum, are biased to the 'conceptional knowledge', 'factual knowledge' and the 'understand' cognitive process dimension. And the remaining dimension of the Bloom's revised taxonomy is very scanty. Comparing with 7th national curriculum, the 2007 revised national curriculum's objectives system has not conspicuous improvement in creativity area. It was suggested to improve present objectives system, because of give learners more experience to opportunity about creativity.