• Title/Summary/Keyword: Bloom

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On Message Length Efficiency of Two Security Schemes using Bloom Filter (블룸필터를 사용하는 두 보안기법에 대한 메시지 길이의 효율성에 대하여)

  • Maeng, Young-Jae;Kang, Jeon-Il;Nyang, Dae-Hun;Lee, Kyung-Hee
    • The KIPS Transactions:PartC
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    • v.19C no.3
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    • pp.173-178
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    • 2012
  • Recent two security schemes showed that a bloom filter can reduce a message length required for representing multiple MACs. The schemes, however, made message length comparison without considering security level. Since the MAC is intended for security, it is important to let multiple MACs and the bloom filter have the same level of security for making message length comparison. In this paper, we analyze the message length efficiency of bloom filter, compressed bloom filter and multiple MACs, letting them have the same security level.

Characteristics of Photosynthetic Pigments during the Outbreak of Harmful Algal Bloom at the South Coastal Area in the Korean Sea Waters

  • Kim, Sook-Yang;Lim, Woel-Ae;Kang, Young-Sil
    • Korean Journal of Environmental Biology
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    • v.28 no.1
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    • pp.20-29
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    • 2010
  • Cochlodinium polykrikoides has occurs regularly during the summer in the South Sea of Korea. To investigate photosynthetic pigments concerned with phytoplankton community structure as bloom of Cochlodinium polykrikoides, the experiment was sampled at 20 stations three times between July and September 2002 in the Southern Sea of Korea. The distribution of peridinin, the biomarker of dinoflagellate, was higher at the blooming time than it was before and it disappeared after bloom. The correlative coefficients between Chl. a and peridinin at the blooming time and out of bloom were 0.9253 and 0.1613, respectively. This result indicated that the bloom was caused by dinoflagellate. The correlative coefficients between Chl. a and fucoxanthin were 0.3282 and 0.9759, respectively, and the correlative coefficients showed the succession from dinoflagellate to diatom. This result means that the bloom of Cochlodinium polykrikoides can be detected by Chl. a information from satellite remote sensing. Therefore, if the algorithm to detect peridinin in addition to Chl. a were to be developed, dinoflagellate red tide could be monitored more effectively.

An Analysis of Bloom's Cognitive Domain Questions in the Home Economics area of the "Technology.Home Economics" Textbooks (중학교 "기술.가정" 교과서의 가정영역에 나타난 Bloom의 인지적 영역 질문 분석)

  • Kim, Hyun-Hee;Park, Mi-Jeong;Chae, Jung-Hyun
    • Journal of Korean Home Economics Education Association
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    • v.22 no.1
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    • pp.97-115
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    • 2010
  • The purpose of this study was to analyze the frequency, level, and location of Bloom's cognitive domain questions in the middle school home economics(HE) text books applied to the 7th curriculum. Analyzed textbooks were selected 15 textbooks per a grade produced from 5 publishing firms. The result of this study followed: First, the biggest number of questions belonged to Bloom's cognitive domain in HE: text was in 1st grade (36.9%), following 2nd(33.6%) and 3th(29.5%). Most questions the HE textbooks according to Bloom's cognitive domain consisted of those about the understanding(28.9%), application(28.3%) and knowledge(21.8%). Second, in case of the location of questions, the subcategory of Questions after Reading occupied 49.2% of all in Bloom's cognitive questions, the case of Questions During Reading was 36.7%, and the subcategory of Questions Before Reading was 14.1%. The rate of understanding questions was the highest as 43.2% in the Bloom's cognitive domain, and the application questions' rate were 28.4%. Analyzed the questions located in questions, the result showed that application-level questions in textbooks were the highest with 36.7%, Regarding to the questions located after Reading, the knowledge question occupied the highest with 33.4%, and next was the understanding questions(26.8%), following the application questions(21,7%).

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Characterization of Blooming on Cucumber Fruits (오이 과실 표면의 과분 발생 특성)

  • Choi, Eung Kyu;Kim, Byung-Soo;Hwang, Un Sun;Do, Han Woo;Suh, Dong Hwan
    • Horticultural Science & Technology
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    • v.31 no.2
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    • pp.159-164
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    • 2013
  • A white powder-like substance, so called 'bloom', is formed on the surface of fruits of many varieties of cucumber. Although it is a natural phenomenon, bloomed fruits are accepted lower in quality compared to bloomless fruits by consumers. The experiments were conducted to obtain basic informations for breeding rootstocks, and to develop promising bloomless rootstocks from basic source materials collected and selected by seed company. The surfaces of bloomless fruits were appeared on the bladder cell of glandular trichome and the epicuticular waxes. Those of bloom fruits appeared with an injured bladder cell and many particles, which were not seen on those of bloomless fruits. The chromaticity was investigated on the surface of the bloom and the bloomless fruits. The 'a' and 'b' value of the bloom and the bloomless fruits did not show any significant difference. The 'L' value was significantly different and that of bloom fruits was higher than that of bloomless fruits. Fruit Si content was conspicuously lower in the fruits of cucumber plants grafted on the bloomless rootstock than in the fruits of those grafted on general bloom rootstocks.

Developmental Characteristic of Cyanobacterial Bloom in Lake Daecheong (대청호의 남조세균 수화 발달 특성)

  • Park Jong-Geun
    • Korean Journal of Environmental Biology
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    • v.23 no.3 s.59
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    • pp.304-314
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    • 2005
  • The occurrence of cyanobacterial bloom in Korean lakes of the summer is generalized. The characteristic of cyanobacterial community was explored. And the developmental stage of cyanobacterial bloom was divided into three phases, 'preparatory phase', 'bloom phase' and 'extinction phase' Cyanobacterial bloom started during the end of June at site 1, transition Bone of Lake Daecheong. The period of water bloom in normal year was about 60~70 days at site 4, lacustrine Bone, but it was unusually 11 days from July 19 in 1999. M. aerugilnosa first occurred in June, had a peak of standing crop curve from the end of August to the beginning of September in 1998 and 2002 and the end of July in 1999 and 2001. The standing crop of M. aeruginosa occupied $68.1\%$ of phytoplankton, $74.2\%$ of cyanobacteria and $88.8\%$ of genus Microcystis, Anabaena spp. first occurred in April, was above 10,000 cells $mL^{-1}$ from the end of August to about the middle of September in 1998. The effect of rainfalls on cyanobacterial bloom was different according to the phases. The rainfalls of preparatory phase assist the growth of cyanobacteria, but accelerate the decrease of cyanobacteria in extinction phase. In bloom phase, the heavy rainfalls reduce the development of the bloom, while the slight ones display only a little effects.

Utilization of Unmanned Aerial Vehicle(UAV) Image for Detection of Algal Bloom in Nakdong River (무인항공영상을 활용한 낙동강 녹조 탐지)

  • Kim, Heung-Min;Jang, Seon-Woong;Yoon, Hong-Joo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.12 no.3
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    • pp.457-464
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    • 2017
  • The large breeding of algae in rivers has caused the algal bloom and has becoming a serious national problem for the safety of water sources. Therefore, in order to supply stable water resources through securing clean water, it is necessary to develop technology for prevention of water pollution caused by algal bloom. The purpose of this study is to improve the water quality management ability of river by applying the algal bloom detection technique using UAV. Unmanned aerial images were acquired for the Dodong in the middle region of the Nakdong River where algal bloom are frequent. In addition, the phytoplankton concentration was acquired through the sampling of algal bloom and the examination of water quality. Correlation between phytoplankton concentrations and the results of applying the algal bloom index to the Unmanned aerial images showed a strong positive correlation. The remote sensing method suggested in this study is expected to improve the initial response capability of river water pollution.

A Hybrid In-network Join Strategy using Bloom Filter in Sensor Network (센서 네트워크에서 블룸 필터를 이용한 하이브리드 인-네트워크 조인 기법)

  • Song, Im-Young;Kim, Kyung-Chang
    • Journal of KIISE:Databases
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    • v.37 no.3
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    • pp.165-170
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    • 2010
  • This paper proposes an in-network join strategy SBJ(Semi & Bloom Join), an efficient join strategy for sensor networks, that minimizes communication cost. SBJ is a hybrid join strategy that can reduce energy consumption by using a bloom filter to reduce the size of data that needs to be sent or received in sensor network. The key to reducing the communication cost in SBJ is to eliminate data not involved in the join result in the early stages of join processing. Through simulation, the paper shows that compared to other join strategies in sensor network, SBJ join strategy is more efficient in reducing the communication cost resulting in a significant reduction in battery consumption.

Influence of Delaying Winter Pruning on Shoot Growth and Fruit Quality of 'Fuji'/M.9 Apple Tree (동계전정 지연이 '후지'/M.9 사과나무의 신초생장 및 과실품질에 미치는 영향)

  • Kweon, Hun-Joong;Sagong, Dong-Hoon
    • Korean Journal of Environmental Agriculture
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    • v.41 no.3
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    • pp.199-205
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    • 2022
  • BACKGROUND: The freezing injury by pruning can be reduced by suspending pruning work when severe cold weather (-23 to -49℃) is forecast. Minimum air temperature of the study area, Gunwi region at February 3, 2012 was -21.9℃, and the subzero temperature continued until April 8, 2012. This study was conducted in two years to investigate the effect of delaying winter pruning until full bloom on shoot growth and fruit quality of 'Fuji'/M.9 apple trees. METHODS AND RESULTS: The time of pruning were March 26 for dormant, April 3 for bud break, and May 2 for full bloom. The winter pruning at full bloom significantly reduced fruit weight for two years compared with the control (winter pruning at dormant), and shoot growth was reduced only in the following year. There was no significant effect of delaying winter pruning at bud break on soluble solid content, fruit red color, return bloom, and pruning weight for two years compared with the control. CONCLUSION(S): These results indicated the delaying winter pruning at bud break of 'Fuji'/M.9 apple tree did not offer any disadvantage over comparable dormant pruning, since the fruit quality was not affected. The delayed pruning at full bloom resulted in decreased fruit weight, though shoot growth, fruit quality, and return bloom were not affected by the delayed pruning. So, the delayed pruning should be considered carefully only for the fruit tree orchards in diseases.

Cloud Storage Security Deduplication Scheme Based on Dynamic Bloom Filter

  • Yan, Xi-ai;Shi, Wei-qi;Tian, Hua
    • Journal of Information Processing Systems
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    • v.15 no.6
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    • pp.1265-1276
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    • 2019
  • Data deduplication is a common method to improve cloud storage efficiency and save network communication bandwidth, but it also brings a series of problems such as privacy disclosure and dictionary attacks. This paper proposes a secure deduplication scheme for cloud storage based on Bloom filter, and dynamically extends the standard Bloom filter. A public dynamic Bloom filter array (PDBFA) is constructed, which improves the efficiency of ownership proof, realizes the fast detection of duplicate data blocks and reduces the false positive rate of the system. In addition, in the process of file encryption and upload, the convergent key is encrypted twice, which can effectively prevent violent dictionary attacks. The experimental results show that the PDBFA scheme has the characteristics of low computational overhead and low false positive rate.