• Title/Summary/Keyword: 망 생존성

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Improvement of Energy Efficiency of LEACH Protocol for Wireless Sensor Networks (무선센서 네트워크를 위한 LEACH 프로토콜의 에너지 효율 향상 방안)

  • Lee, Sang-Hoon;Suk, Jung-Bong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.2B
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    • pp.76-81
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    • 2008
  • LEACH (Low Energy Adaptive Clustering Hierarchy) has been proposed as a routing protocol with a hierarchical structure, in order to achieve the energy efficiency that is of primary importance in the wireless sensor networks. A wireless sensor network adopting LEACH is composed of a few clusters, each of which consists of member nodes that sense the data, and head nodes that deliver the collected data from member nodes to a sink node that is connected to a backbone network. A head node in a cluster allocates TDMA slots to its member nodes without taking into account whether they have data to transmit or not, thus resulting in inefficiency of energy usage of head node that remains in active mode during the entire round time. This motivates us to propose a scheme to improve the energy efficiency of LEACH, by assigning TDMA slots only to those member nodes who have data to send. As a result, the head node can remain sleep during the period of no data transmission from member nodes, leading to the substantial energy saving. By using the ns-2 simulator, we evaluate the performance of the proposed scheme in comparison with the original LEACH. Experimental results validate our scheme, showing a better performance than original LEACH in terms of the number of outliving nodes and the quantity of energy consumption as time evolves.

Classification of the Diagnosis of Diabetes based on Mixture of Expert Model (Mixture of Expert 모형에 기반한 당뇨병 진단 분류)

  • Lee, Hong-Ki;Myoung, Sung-Min
    • Journal of the Korea Society of Computer and Information
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    • v.19 no.11
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    • pp.149-157
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    • 2014
  • Diabetes is a chronic disease that requires continuous medical care and patient-self management education to prevent acute complications and reduce the risk of long-term complications. The worldwide prevalence and incidence of diabetes mellitus are reached epidemic proportions in most populations. Early detection of diabetes could help to prevent its onset by taking appropriate preventive measures and managing lifestyle. The major objective of this research is to develop an automated decision support system for detection of diabetes using mixture of experts model. The performance of the classification algorithms was compared on the Pima Indians diabetes dataset. The result of this study demonstrated that the mixture of expert model achieved diagnostic accuracies were higher than the other automated diagnostic systems.

A study on Survive and Acquisition for YouTube Partnership of Entry YouTubers using Machine Learning Classification Technique (머신러닝 분류기법을 활용한 신생 유튜버의 생존 및 수익창출에 관한 연구)

  • Hoik Kim;Han-Min Kim
    • Information Systems Review
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    • v.25 no.2
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    • pp.57-76
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    • 2023
  • This study classifies the success of creators and YouTubers who have created channels on YouTube recently, which is the most influential digital platform. Based on the actual information disclosure of YouTubers who are in the field of science and technology category, video upload cycle, video length, number of selectable multilingual subtitles, and information from other social network channels that are being operated, the success of YouTubers using machine learning was classified and analyzed, which is the closest to the YouTube revenue structure. Our findings showed that neural network algorithm provided the best performance to predict the success or failure of YouTubers. In addition, our five factors contributed to improve the performance of the classification. This study has implications in suggesting various approaches to new individual entrepreneurs who want to start YouTube, influencers who are currently operating YouTube, and companies who want to utilize these digital platforms. We discuss the future direction of utilizing digital platforms.

Morphological Characteristics of Tricholoma matsutake Ectomycorrhiza (송이 외생균근(外生菌根)의 형태적(形態的) 특징(特徵))

  • Koo, Chang-Duck
    • Journal of Korean Society of Forest Science
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    • v.94 no.1 s.158
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    • pp.16-20
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    • 2005
  • Tricholoma matsutake ectomycorrhizas are unique in their morphology: not bifurcated broom shaped roots with not easily wettable brilliant and profuse white hyphae. To understand these characteristics the ectomycorrhizas were investigated with electron microscopy. T. matsutake ectomycorrhiza have thin mantle and typical Hartig net development in the epidermis and cortex, but no fungal mantle on the root apex. There were no penetrating hyphae inside of the cells of either epidermis, cortex or stele. Inside of the walls of epidermis and cortex cells are lined with ca. $2{\mu}m$ hemispherical amyloplasts. The brilliant hyphal surface was covered with various fine amorphous granules. The hyphal cell wall was thin membrane less than $0.3{\mu}m$ thick. There is no clamp connection on the hyphae. This thin membraneous cell wall with high elasticity can be related to survival strategy of the species without plasmolysis under frequent soil water stress environment. And the coarse hyphal surface with some water repellency can control sudden inrush of water of the hyphae with an extremely low osmotic potential. It is concluded that no mantle on the tip can induce mycorrhizas not bifurcated and that finely coarse surface of T. matsutake hyphae can make the hyphae brilliantly white but less wetted.

Exploratory Study on the Application of Blockchain for ESG Management in the Distribution Industry (유통업계 ESG 경영을 위한 블록체인 도입 탐색적 연구)

  • Yeji Choi;Jaewook Byun;Jiwon Moon;Hangbae Chang
    • Knowledge Management Research
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    • v.24 no.3
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    • pp.217-237
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    • 2023
  • Recently, in the face of successive and unexpected global economic risks, ESG(Environmental, Social, and Governance) management has risen as an essential survival strategy for businesses. Particularly, the supply chain disruptions due to the COVID-19 pandemic have added to the uncertainty of risks, heightening the importance of ESG management in the distribution industry. In this context, the role of blockchain technology in strengthening and managing the connection between the distribution industry and ESG management has become increasingly significant. While there have been extensive proposals for business models that integrate blockchain technology into distribution, few studies have specifically focused on the feasibility and effectiveness of applying blockchain to ESG management in this field. Therefore, this study analyzed the relationship between blockchain and ESG management in the distribution industry by employing association analysis, a text mining technique, on Korean academic research. Through this, the study confirmed the possibility of implementing blockchain in the distribution industry's ESG management and presented keywords to guide future research directions. The findings obtained from this study are expected to be utilized as foundational research for future studies in constructing blockchain-based business models for ESG management in the distribution industry.

A Study on Religious Tendency shown in 「Gyeongseol」 by Jinam Lee Byeong-hun (진암(眞庵) 이병헌(李炳憲)의 「경설(經說)」에 나타난 종교적 성향)

  • Lee, Sang-Ha
    • (The)Study of the Eastern Classic
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    • no.41
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    • pp.385-406
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    • 2010
  • Lee Byeong-hun was introduced to Hanjuhak when he was taught by Myeonwoo Gwak Jong-seok. It is assumed that Hanjuhak circles had a certain influence on formation of his ideas in that they had liberal tendency at that time. Lee Byeong-hun accepted Geummungyonghak developed by Gang Yu-wee of China and participated in Confucian Science Movement while excluding Confucianism. After he accepted western civilization and the ideas of Gang Yu-wee, no traces of Hanjuhak was found in his writing, but it is assumed that Hanjuhak might work as a nutritious element for his ideas. He thought that religious nature of Confucianism could be revived only when he left Neo-confucianism which changed Confucianism into a philosophy by insisting reason instead of God. So, he respected Confucius as a religious founder and left such concepts as reason and respect which were considered important in Neo-confucianism and valued disposition and faith in "Jungyong", a doctrine of the Mean. He considered Confucianism as religious and joined in religious practices such as praying and reciting scriptures. He insisted that filial piety indicates a filial son of the Heaven when interpreting the following passage: Shun (Chinese leader) is a filial duty, which is assumed that he was influenced by Christianity. He respected Confucius as the only religious founder and God as the God to make Confucianism a religion. It is believed that he considered only Confucius as a founder instead of traditional Confucian sages as religion such as Buddhism and Christianity has one founder. God he thought is related with the God in Christianity and furthermore accepted reincarnation of Buddhism which is contrary to Confucian ideas. According to "Gyeongseol" by Lee Byeong-hun, it was believed that he was engaged in religion based on a faith that Confucianism is a religion rather than he pursued Confucianism as a religion to find out a way of its survival.

Cultivation of Ginseng in Baengnyeongdo, the Northernmost Island of the Yellow Sea in South Korea (서해 최북단 섬 백령도의 인삼 재배 현황)

  • Cho, Dae-Hui
    • Journal of Ginseng Culture
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    • v.4
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    • pp.128-141
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    • 2022
  • Baengnyeongdo Island, which belongs to Ongjin-gun, Incheon, is an island in the northernmost part of the West Sea in South Korea. Baengnyeong Island is the 15th largest island in Korea and covers an area of 51 km2. The Korea Ginseng Corporation (KGC) investigated the possibility of growing ginseng on Baengnyeong Island in 1996. In 1997, thanks to the support of cultivation costs from Ongjin-gun, the first ginseng seedbed was built on Baengnyeong Island. In 1999, the seedlings were transplanted to a permanent field under a contract with KGC. In 2003, the first six-year-old ginseng harvest was performed, and KGC purchased all production according to the contract. Since then, KGC has signed on to grow ginseng until 2012 and purchased six-year-old ginseng until the fall of 2016. Since 2014, the GimpoPaju Ginseng Agricultural Cooperative Association has signed a ginseng production contract. According to a survey of nine 6-year-old ginseng fields (total 5,961 units) on Baengnyeong Island, the top five with good growth had a survival rate of 42.6 to 68%, and the bottom four with poor growth had an extremely low survival rate of 11.1 to 21.3%. The four fields with low survival rates were where hot peppers were planted before ginseng cultivation. It is believed that the excess nitrogen remaining in the soil due to the treatment of compost or manure during pepper cultivation causes ginseng roots to rot. The average incidence of Alternaria blight was 8.6%. Six six-year-old ginseng gardens were low at 1.1 to 4.7%, while the other three were high at 16.7 to 20.9%. It is assumed that the reason for the low survival rate and high incidence of Alternaria blight is a rain-leaking shield. Farmers used rain-leaking shields because the precipitation on Baengnyeong Island was smaller than on land. One field showed 3% of leaves with yellowish brown spots, a symptom of physiological disturbance of the leaf, which is presumed to be due to the excessive presence of iron in the soil. To increase the production of ginseng on Baengnyeong Island, it is necessary to develop a suitable ginseng cultivation method for the island, such as strengthening the field management based on the results of a scientific study of soil, using rain-resistant shading, and installing drip irrigation facilities. I hope that ginseng will become a new driving force for the development of Baengnyeong Island, allowing ginseng products and food to thrive in the beautiful natural environment of the island.

Understanding the Effects of Accelerators on Startups: A Network-Based Approach (액셀러레이터가 스타트업에 미치는 영향 고찰: 네트워크 관점을 중심으로)

  • Ra, Keehyuk;Yang, Daegyu;Battulga, Altantsetseg
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.14 no.1
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    • pp.85-99
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    • 2019
  • Startups need proper external supports to survive and build strong foundations for growth in their early stage. Accelerators help such startups by providing tangible and intangible resources. Accordingly, accelerators are creating a social environment that can effectively support the startups in the early stage, distinct from other institutions that fund or help the startups. However, the actual impact of accelerators on startups has not been yet fully scrutinized thoroughly, especially with the lack of theoretical lenses to comprehend accelerators. This paper aims to build a theoretical foundation to understand the role of accelerator, focusing on the network-based perspective. We briefly overview the concept of accelerator and the current status of the accelerator industry. Subsequently, focusing on the network that accelerators and startups create, this paper examines how the characteristics of the network relationships affect the growth and survival of the early-stage startups. Thus, by offering systematic analysis of the underlying mechanisms of the effects of the accelerators under network-based approach, this paper suggests a direction for the future empirical research on the topic of startup accelerator.

대구 수정란의 질병 제어에 의한 부화율 향상 연구

  • 박상언;권문경;이채성;김완기;이정용
    • Proceedings of the Korean Aquaculture Society Conference
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    • 2003.10a
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    • pp.64-64
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    • 2003
  • 대구 인공종묘 생산 기술 개발의 일환으로 수정란에 기생하여 폐사를 유발하는 세균 및 세균 감염 경로를 파악함으로써 수정란의 생존율과 부화율 향상을 위하여 본 실험을 실시하였다. 세균 감염 경로를 파악하기 위하여 난소와 정소 자체 세균 감염 여부를 조사하였다. 일반배지 (BHIA)와 비브리오 선택배지 (TCBS)를 사용하여 세균검사를 실시하였다. 난소의 세균 검사는 생식소 내부를 일부 절개한 후 멸균 roop를 찔러 세균을 검사하였고, 정소는 채정하기 전 복부를 절개하여 멸균 roop로서 적출하여 배지에 도말한 후 배양하였다. 수정란 내 세균 수는 수정란을 각각 20개씩 샘플하여 난 외부에 기생하는 세균을 제거하기 위하여 난소독제로 이용되고 있는 benzalkonium 0.1%로 1분간 소독한 후 멸균 생리식염수로 3회 세척하여 호모게나이즈하여 검사하였다. 호모게나이즈한 액 중 100${\mu}\ell$를 pipetting하여 일반배지(BHIA)에 도말하여 인큐베이터에서 배양하였다. 난소와 정소 내에서 세균이 검출됨에 따라 수정 시 세균 감염을 억제하기 위하여 자외선 살균해수와 일반해수를 수정액으로 사용하여 발생율을 비교 시험하였다. 수정 시간은 1분으로 동일하게 적용하였으며, 수정 용기는 멸균 처리된 일회용 100$m\ell$ 플라스틱 용기를 사용하였다. 수정 후 과다한 정자를 제거하기 위한 세란은 1$\ell$ 멸균 비이커에서 5회 30분 가량 실시하여 정자를 제거하였고 멸균 봉으로 저어주면서 수정란의 점착력을 제거하였다. 수정란은 100$\mu\textrm{m}$ 그물망으로 수정란 유실을 방지한 플라스틱 용기에 수용하여 유효수량 270$\ell$ FRP 수조에 수용하여 3$\ell$/min 환수하였고, 수온은 자연수온 1$^{\circ}C$로 유지하였다. 발생율은 만능투영기로 3회 측정하였다. 수정 후 세균과 기생충에 의한 수정란의 폐사를 억제하기 위하여 수정 직후, 수정 후 1일, 2일째 oxytetracycline과 iodine 처리에 따른 발생율 변화를 조사하였다. 발생율은 만능투영기로 조사하였고, 시험구별로 3회 측정하였다. 경과 일수별로 약제 처리는 약제 미처리 수정란 중 정상적인 발생이 이루어지고 있는 것을 선별하여 조사하였다. 약제 처리에 따른 배체 발생 단계는 수정 후 1일째는 상실기, 2일째는 포배기였다. 수정란 및 대구 자어에서 분리된 V. splendidus 에 의한 폐사를 예방하기 위해 in vivo에서 oxytetracycline 외 5종의 항생제를 대상으로 96well plate에서 최고 농도 250ppm부터 2 fold로 단계 희석하여 $25^{\circ}C$에서 48시간 배양하여 MIC를 조사하였다. 세균 감염경로 파악을 위하여 난소, 정소 및 정자에서 세균을 분리한 결과 일반배지 및 비브리오 선택배지에서 모두 균이 검출되었고, 균 동정 결과 터봇 자어에서 검출된 것으로 보고된(Gatesoupe et al., 1999) V. splendidus로 나타났다. 수정액과 정자 및 미수정란의 세균 분리 결과 일반배지에서 3$\times$10/ml ~ 7$\times$10/ml로 균이 검출되었다. 수정액을 일반해수와 자외선 살균 해수를 사용하여 발생율을 비교한 결과 수정 후 3일째 발생율은 자외선 살균해수 72.3%, 일반해수 52.7%였으며, 수정 후 7일째 40.9%와 25.1%로 자외선 살균해수가 유의적으로 높게 나타났다. 수정 후 경과 일수별로 oxytetracycline과 Iodine을 처리한 결과 수정 직후 처리한 시험구는 7일째 19.8%와 18.9%로 대조구 23.1%와 유의적인 차이가 없는 것으로 나타났다. 수정 후 1일째 처리한 시험구는 54.5%와 56.8%, 수정후 2일째 처리구는 47.9%와 50.6%로 두 시험구 모두 대조구와 수정 직후 처리구보다 유의적으로 높게 나타났다. 수정란 및 대구 자어에서 분리된 V. splendidus 에 의한 폐사를 예방하기 위해 in vivo에서 항생제 종류별 MIC 조사 결과 oxytetracycline이 0.48ppm으로 가장 효과가 높은 것으로 나타났다.

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Effects of Suspended Solid and Cadmium on the Shallow-sea Ecosystem II. Acute and Chronic Toxicity of Cadmium to a Herbivorous Copepod, Tigriopus japonicus (천해역 먹이망 생태계에 대한 무기부유입자와 카드뮴의 영향 II. Tigriopus japonicus에 대한 카드뮴의 급성 및 만성독성)

  • CHUNG Ee-Yung;SHIN Yun Kyung;YIH Wonho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.29 no.1
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    • pp.124-133
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    • 1996
  • A herbivorous copepod, Tigriopus japonicus, was tested to study its acute and chronic responses to Cd tonicity. Under $20^{\circ}C,\;96hr-LC_{50}$ of T. japonicus in medium with $32\%_{\circ},\;26\%_{\circ},\;and\;18\%_{\circ}$ salinity were 11.1 ppm, 13.7 ppm, and 9.7 ppm, respectively. The $96hr-LC_{50}$ in medium with $32\%_{\circ},\;26\%_{\circ},\;and\;18\%_{\circ}$ salinity increased to 21.6 ppm, 15.0 ppm, and 11,0 ppm, respectively under $10^{\circ}C$ condition. Oxygen consumption rates during 96hrs exposure to Cd toxicity decreased more sharply at $20^{\circ}C$ than those at $10^{\circ}C$. Survival rate and $250dys-LC_{50}$ of T. japonicus in medium with $32\%_{\circ}$ salinity, in concentration of Cd 4 ppm were $5\%$ and 0.05 ppm, respectively under $10^{\circ}C$, and $0\%$ and 0.20 ppm under $20^{\circ}C$. It was that the copepod selectively feed on Skeletonema costatum, Nitzschia pungens, N. seriata, and Rhizosolenia hebetata f. semispina.

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