• Title/Summary/Keyword: perfect number

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International R&D Contest with IPR Coordination and Cost Externality

  • Lee, Sanghack;Nam, Bo-Ra
    • Journal of Korea Trade
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    • v.23 no.5
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    • pp.118-128
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    • 2019
  • Purpose - This paper examines the international R&D contest in which the extent of intellectual property right (IPR) affects both the size of prize for the winning firm and the extent of positive spillover through cost of firms. Recognizing the possibility of incomplete protection of IPR, the present paper analyzes the effect of changes in the extent of IPR on payoffs to firms and social welfare. Design/methodology - This paper examines coordination of IPRs by countries in economic integration. The paper then develops a general model of international R&D contest with incomplete protection of IPR. An increase in the extent of IPR augments the share of the prize the winning firm can appropriate, while decreasing the positive cost externality. To derive sharper results, the paper considers the cases of linear and fixed spillovers. Findings - Under plausible assumptions, an increase in the IPR augments the payoff to each firm and the aggregate payoffs as well. The paper also shows that the number of firms participating in the R&D contest can be endogenously determined in the two-stage R&D contest. The higher the extent of cost spillover, and the larger the effective prize, the more firms participate in the international R&D contest. Originality/value - Existing studies assume that firms winning the R&D contest enjoy perfect IPR to the output of their R&D activities. This is a very restrictive assumption in that other firms can copy the new products or processes. By allowing for the incompleteness of the IPR, the present paper develops a more realistic model of R&D contest. The novelty of the present paper is to allow for the possibility that the higher extent of IPR increases the prize and decreases positive cost externality at the same time. The findings of the present paper can serve as a basis for government policy toward R&D activities of firms and protection of IPRs.

Deobfuscation Processing and Deep Learning-Based Detection Method for PowerShell-Based Malware (파워쉘 기반 악성코드에 대한 역난독화 처리와 딥러닝 기반 탐지 방법)

  • Jung, Ho-jin;Ryu, Hyo-gon;Jo, Kyu-whan;Lee, Sangkyun
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.32 no.3
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    • pp.501-511
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    • 2022
  • In 2021, ransomware attacks became popular, and the number is rapidly increasing every year. Since PowerShell is used as the primary ransomware technique, the need for PowerShell-based malware detection is ever increasing. However, the existing detection techniques have limits in that they cannot detect obfuscated scripts or require a long processing time for deobfuscation. This paper proposes a simple and fast deobfuscation method and a deep learning-based classification model that can detect PowerShell-based malware. Our technique is composed of Word2Vec and a convolutional neural network to learn the meaning of a script extracting important features. We tested the proposed model using 1400 malicious codes and 8600 normal scripts provided by the AI-based PowerShell malicious script detection track of the 2021 Cybersecurity AI/Big Data Utilization Contest. Our method achieved 5.04 times faster deobfuscation than the existing methods with a perfect success rate and high detection performance with FPR of 0.01 and TPR of 0.965.

New records of two alien plants, Juncus torreyi (Juncaceae) and Egeria densa (Hydrocharitaceae) in Korea

  • Jongduk JUNG;Hye Ryun NA;Kyu Song LEE;Yeongmin CHOI;Woongrae CHO;Jin-Oh HYUN
    • Korean Journal of Plant Taxonomy
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    • v.53 no.1
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    • pp.54-59
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    • 2023
  • Naturalized populations of two alien plants were newly found, and we describe their morphological characteristics and habitats with photographs. One is a member of Juncaceae, Juncus torreyi Coville, and was newly found at a pool of a beach in Gangwon-do. This rush is native to North America and belongs to the sect. Ozophyllum (subgen. Juncus) according to certain morphological characteristics, such as its racemose inflorescence, the absence of floral bracteole, and unitubular leaves with perfect septa. J. torreyi is easily distinguishable from Korean rushes by its long rhizomes with swollen nodes and globular head with 25-100 flowers. Its introduction into Japan and Europe was reported, but the ecological risk associated with its over-dispersal is not known. The other alien plant is a submerged plant, Egeria densa Planch. (Hydrocharitaceae), which was found in streams in Gyeongsangbuk-do and ditches in the Busan-si area, both of which being in the watershed of the Nakdong River. Egeria densa is similar to Hydrilla verticillata (L.f.) Royle, which is native to Korea. However, it is distinguished from H. verticillata by its larger flowers and lack of overwintering organs. This alien plant is native to South America and was introduced for aquarium gardening and naturalized around the world. Egeria densa is treated as a malignant weed due to its asexual reproduction and rapid growth. Size changes and the number of populations of E. densa must be investigated.

Problems and suggested improvement plans for occupational health service in Korea

  • Dongmug Kang
    • Annals of Occupational and Environmental Medicine
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    • v.35
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    • pp.10.1-10.10
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    • 2023
  • The purpose of this paper was to review the problems relating to Korea's occupational health services and suggest ways to improve them. Korea can be classified as a welfare state type of conservative corporatism partially interwoven with liberalism. While experiencing compressed economic growth, the economic sectors of developed (excess areas) and developing (deficient areas) countries are interwoven. Therefore, it is necessary to perfect conservative corporatism along with a complementary reinforcement of liberal contents and to apply a multilayered approach focusing on complementing the deficient areas. It is essential to form a national representative indicator related to occupational health, and a strategy for selection and concentration is needed. The proposed central indicator is the occupational health coverage rate (OHCR), which is the number of workers who have applied for mandatory occupational health services under the Occupational Safety and Health Act in the numerator with the total working population in the denominator. This paper proposes ways to raise the OHCR, which is currently at the level of 25%-40%, to 70%-80%, which is the level of Japan, Germany, and France. To achieve this target, it is necessary to focus on small businesses and vulnerable workers. This is an area of market failure and requires the active input of community-oriented public resources. For access to larger workplaces, the marketability of services should be strengthened and personal intervention using digital health resources should be actively attempted. Taking a national perspective, work environment improvement committees with tripartite (labor, management, and government) participation for improvement of the working environment need to be established at the center and in the regions. Through this, prevention funds linked to industrial accident compensation and prevention could be used efficiently. A national chemical substance management system must be established to monitor the health of workers and the general public.

Effects of Different Nitrogen Levels and Planting Densities on the Quality and Yield of the Black Rice Cultivar 'Shinnongheugchal' (재식밀도 및 시비량 차이가 신농흑찰 품질 및 수량에 미치는 영향)

  • Lee, In-Sok;Lee, Deok-Ryeol;Cho, Seung-Hyun;Lee, Song-Yi;Kim, Kab-Cheol;Lee, Ki-Kwon;Song, Young-Ju
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.61 no.2
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    • pp.79-86
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    • 2016
  • The late-maturing black rice cultivar Shinnongheugchal from Jeollabuk-do Agricultural Research and Extension Service was used as the plant material for estimating growth characters, quality and yield from the vegetation period to harvest age. This study was performed to select an optimum combination of nitrogen level and planting density for the maximum yield of Shinnongheugchal. The plant height, number of tillers, and SPAD index were higher when the combination of 70 hills per $3.3m^2$ and 13 kg/10 a nitrogen level was used at 30 days after transplanting. The heading date for the combination of 70 hills per $3.3m^2$ and 15 kg/10 a nitrogen level, and 80 hills per $3.3m^2$ and 15 kg/10 a nitrogen level was August 22. The heading date for the other combinations was August 21. The combination of 70 hills per $3.3m^2$ and 13 kg/10 a nitrogen level yielded the highest number of tillers at 40 days after flowering. Even though the lodging index was increased with increasing nitrogen levels, field lodging did not occur until harvest time. Seed nitrogen concentration in the combination of 70 hills per $3.3m^2$ and 13 kg/10 a nitrogen level showed a significant difference when compared with the other combinations. The black rice yield varied significantly, and the highest yield was observed in the combination of 70 hills per $3.3m^2$ and 13 kg/10 a nitrogen level. The yield was significantly correlated with seed nitrogen concentration. The maximum yield was estimated to be 14.67 kg/10 a nitrogen level by using the regression equation. On average, the coloring degree of the black rice was higher at planting density of 70 hills per $3.3m^2$ than at 80 hills per $3.3m^2$. The highest yield of perfect black rice was obtained using the combination of 70 hills per $3.3m^2$ and 13 kg/10 a nitrogen level. Our findings demonstrate that a nitrogen level of 13-14 kg/10 a can be used to obtain the maximum yield from Shinnongheugchal with yield, cyanidin 3-glucoside content, and perfect black rice yield as the standard.

Learning from the USA's Single Emergency Number 911: Policy Implications for Korea (미국 긴급번호 911 운영시스템에 관한 연구: 긴급번호 실질적 통합을 위한 정책 시사점 제시 중심으로)

  • Kim, Hak-Kyong;Lee, Sung-Yong
    • Korean Security Journal
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    • no.43
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    • pp.67-97
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    • 2015
  • In Korea, a single emergency number, such as 911 of the USA and 999 of the UK, does not exist. This issue became highly controversial, when the Sewol Ferry Sinking disaster occurred last year. So, the Korean government has planned to adopt a single emergency number, integrating 112 of the Police, 119 of the Fire and Ambulance, 122 of the Korean Coast Guard, and many other emergency numbers. However, the integration plan recently proposed by the Ministry of Public Safety Security seems to be, what is called, a "partial integration model" which repeals the 122 number, but still maintains 112, 119, and 110 respectively. In this context, the study looks into USA's (diverse) 911 operating system, and subsequently tries to draw general features or characteristics. Further, the research attempts to derive policy implication from the general features. If the proposed partial integration model reflects the policy implications, the model can virtually operate like the 911 system -i.e. a single emergency number system - creating inter-operability between responding agencies such as police, fire, and ambulance, even though it is not a perfect integration model. The features drawn are (1) integration of emergency call-taking, (2) functional separation of call-taking and dispatching, (3) integration of physical facilities for call-taking and dispatching, and (4) professional call-takers and dispatchers. Moreover, the policy implications derived from the characteristics are (1) a user-friendly system - fast but accurate responses, (2) integrated responses to accidents, (3) professional call-taking and dispatching & objective and comprehensive risk assessment, and finally (4) active organizational learning in emergency call centers. Considering the policy implications, the following suggestions need to be applied to the current proposed plan: 1. Emergency services' systems should be tightly linked and connected in a systemic way so that they can communicate and exchange intelligence with one another. 2. Public safety answering points (call centers) of each emergency service should share their education and training modules, manuals, etc. Common training and manuals are also needed for inter-operability. 3. Personal management to enable-long term service in public safety answering points (call centers) should be established as one of the ways to promote professionalism.

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Capacity of Opportunistic Incremental Relaying System Controlled by Truncated Power in Rayleigh Fading Channels (Rayleigh 페이딩 채널에서 Truncated 전력 제어된 기회전송 추가 릴레이 시스템의 전송용량)

  • Kim, Nam-Soo
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.1
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    • pp.117-124
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    • 2015
  • Recently an opportunistic incremental relaying (OIR) system has been studied for improving the performance degradation in fading channel. However there are few studies on power control in the system, and the studies are assumed perfect knowledge of the all channels at transmitters. The assumption that the source know all channel information is difficult in practical channels. Therefore, in this paper we assume that the source knows partial channel information and propose a modified truncated channel inversion (TCI) power control scheme for the OIR system. We derive the channel capacity of the proposed system and perform Monte Carlo simulation. It is noticed that the proposed OIR system has better capacity than that of the power controlled system with direct path only, and the capacity increases with the number of relays. The power controlled OIR system gained more capacity of 29.7%, 32.7%, and 33.5% than that of the system with direct path only for the number of relays of 1, 3, and 5, respectively. The results from this paper can be applied to the estimation of a theoretical capacity for the currently operating cellular systems when they adopt the IOR system.

Effects of Damage by Brown Planthopper at Ripening Stage on Yield and Quality of Rice (벼 등숙기 벼멸구 피해가 수량 및 품질에 미치는 영향)

  • Lee, Jong-Hee;Yeo, Un-Sang;Kwak, Do-Yeon;Kim, Joon-Hwan;Song, Yu-Cheon;Kim, Choon-Song;Shin, Moon-Sik
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.51 no.spc1
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    • pp.73-76
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    • 2006
  • This study was carried out to investigate the change yield and grain quality in rice caused by damages of brown planthopper (Bph) on major agronomic traits at the ripening stage. A major agronomic traits such as culm length, panicle length, number of panicle and number of grain per panicles was no-significant difference compared hopperburn area (HBA) and moderately damaged area (MDA) by brown planthopper with non-damaged area (NDA). but, the ripeing ratio and yield in HBA and MDA was significantly decreased. The perfect rice of brown rice in HBA and MDA was also lowered than the NDA and the immatured grain among imperfect rice in damaged area by BPH was significantly increased than in the NDA. Among the traits related with palatability of cooked rice, the amylose content was not affected by damage of brown planthopper, whereas, the protein content was significantly increased in the HBA and MDA. additionally, Peak viscosity in HBA and MDA is lower than the NDA, and setback was increased. In most cases, there was negative on yield and grain quality by the damage of brown planthopper at the ripening stage. Thus, the rice product harvested in damaged area should be separated with that in non damaged area for grain market quality of milled rice.

Enrollment Elevation to the Chinese International Students in Local Universities in Korea (한국 지방대학의 중국유학생 유치·관리방안)

  • Chung, Kyoun-Sup;Lei, Song-Lin;Sim, Moon-Bo
    • The Journal of the Korea Contents Association
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    • v.10 no.8
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    • pp.327-340
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    • 2010
  • Since South Korea has problems existing in the respects of educational resources, environment, policies, etc., local universities of South Korea have been in an inferior position in the competition of overseas student enrollment. With increasingly deepening of cultural exchange between China and South Korea, due to geographic close relationship between the two countries, a great number of South Korean students go to China for study; also, Chinese students have increasingly become the important target of recruitment by all local universities in South Korea. In recent years, with rapid increase in the number of Chinese students in South Korea, the overseas student education system of South Korea has been progressed continuously. Compared with educational advantages of universities in European, American developed countries, and the capital region of South Korea, however there still exists a lot of problems in Chinese student recruitment by local universities. The major findings of the study can be summarized as follows. There exist not only some advantages but also some problems to be addressed urgently in Chinese student enrollment by South Korean local universities. How to build a distinctive recruitment environment suitable for Chinese students; and, how to develop a complete "one-stop" educational system suitable for study; and, how to make a strategy of development for Chinese students; and, how to perfect set up the overseas students' education management system; which are the remaining tasks to be solved for. To achieve a win-win for both overseas students and South Korean local universities, it is very important and urgent works to do for administrators of Chinese students in all local universities of South Korea.

The Degree of Female Undergraduates' Perceived Risk of Smoking (여대생의 흡연에 대한 위험지각도)

  • Kang, Hyun-Sook
    • The Journal of the Korea Contents Association
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    • v.9 no.9
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    • pp.259-267
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    • 2009
  • This study intends to figure out the variables affecting the degree of female undergraduates' perceived risk of smoking and utilize them as foundational data for educating them to quit smoking. Thereupon, it conducted a self-administered survey from May 18 till 25 of 2009 to 231 female undergraduates attending S University located in Gyeonggi-do. The study tool contains 19 items of general characteristics and 8 of the degree of perceived risk of smoking. The data collected were analyzed by SPSS program, and the following results were gained. 1. According to the result on the degree of female undergraduates' perceived risk of smoking, the degree was shown high as the average was 4.32 among the perfect score of 5; thus, the degree of perceived risk of smoking was high. 2. In terms of the household economic level, female undergraduates with the lower economic level indicated the higher degree of perceived risk of smoking. There existed significant difference by their economic level (F=7.14, p<.01). 3. In regard of whether the female undergraduate smokes or not, the non-smoker perceives the degree of risk of smoking more highly than the smoker does; there is significant difference by whether they smoke or not (t=-2.43, p<.05). 4. About the number of friends who smoke, female undergraduates with one smoking friend show the highest degree of perceived risk of smoking. Those haying three or more smoking friends indicate the low degree of perceived risk of smoking. There exists significant difference by the number of smoking friends they have (F=3.14, p<.05). 5. According to the degree of perceived risk of smoking by their school life satisfaction, the female undergraduates expressing 'dissatisfaction' show the highest degree of perceived risk of smoking while 'satisfaction' indicates the average level. This was statistically significant difference (F=4.81, p<.01). Therefore, it is thought that it will be necessary to develop programs based on this research which can allow female undergraduates to team the importance of quitting smoking and actively participate in the education for it.