• Title/Summary/Keyword: Link Stability

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A Performance Analysis and Evaluation of Congestion Avoidance Algorithm for ABR service over ATM Networks (ATM망에서 ABR 서비스를 위한 혼잡회피 알고리즘의 성능 분석 및 평가)

  • 하창승;조익성
    • Journal of the Korea Society of Computer and Information
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    • v.7 no.3
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    • pp.80-91
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    • 2002
  • A general goal of the AT%(Asynchronous Transfer Mode) network is to support connect across various network. On ATM networks, ABR services are provided using the remained ban after allocation CBR and VBR traffic. Realtime services such as transmitting audio or video data may be provided using CBR ado VBR which have a constrained transmission delay, but in these cases, the communications bandwidth may be wasted. In this paper a simulation has been performed to compare and evaluate the performance between the ERICA(Explicit Rate Indicate Avoidance) and EPRCA(Enhanced Proportional Rate Control Algorithm) switches which use Explicit Rate switch algorithm for ABR switch. The variation of the ACR at the source end system, the queue length, the utilization rate of the link bandwidth and the share fairness at the transient and steady states are used as the evaluation criteria for the simulation. As a result of simulation, ERICA algorithm switch was ten times long compared to ERPCA switch to achieve assigned fair share. so EPRCA switch is superior to ERICA about load response. For Fair share and stability, ERICA switch is excellent to EPRCA switch.

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Development of Small Farms in the Agro-Industrial Complex

  • Petrunenko, Iaroslav;Pohrishchuk, Oleg;Plotnikova, Mariia;Zolotnytska, Yuliia;Dligach, Andrii
    • International Journal of Computer Science & Network Security
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    • v.21 no.3
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    • pp.287-294
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    • 2021
  • Modern small farms are important link components in the structure of the world agro-industrial complex. It ensures the food and nutritional sustainability of the country exclusively at the local regional level. The purpose of the research is to examine the role of farming in ensuring nutritional security and food stability based on the analysis of the Food Sustainability Index (FSI). Research methods: modeling, abstraction, analogy, analysis, synthesis, formalization, logical abstraction, theoretical cognition, systematization and classification, abstract-logical, etc. Results. Having analyzed the Food Sustainability Index for 2018, it has been established that there is a lack of a clear relationship between the pace of economic development and the level of food and nutritional sustainability. In addition, this study has identified the countries with the largest number of small farms, as well as the number of farms within the region. The correlation between the size of the farm and the area of agricultural land that it cultivates has been determined. The problems faced by small farms in the process of their activity have been analyzed. The programs implemented in the field of agro-industrial complex development by international profile institutions have been systematized. Particularly, the regional structure of agricultural development programs under the guidance of IFAD is defined, as well as the areas to which they are directed. Specific measures taken by governments to stimulate the development of small farms have been outlined. Reasonable conclusions have been formed based on the study. The direction of future research is seen in the assessment of the export potential of small farms in terms of range, volume of export deliveries and geographical direction of movement of their products.

Advantages and disadvantages of renewable energy-oil-environmental pollution-from the point of view of nanoscience

  • Shunzheng Jia;Xiuhong Niu;Fangting Jia;Tayebeh Mahmoudi
    • Advances in concrete construction
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    • v.16 no.1
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    • pp.69-78
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    • 2023
  • This investigation delves into the adverse repercussions stemming from the impact of arsenic on steel pipes concealed within soil designated for rice cultivation. Simultaneously, the study aims to ascertain effective techniques for detecting arsenic in the soil and to provide strategies for mitigating the corrosion of steel pipes. The realm of nanotechnology presents promising avenues for addressing the intricate intersection of renewable energy, oil, and environmental pollution from a novel perspective. Nanostructured materials, characterized by distinct chemical and physical attributes, unveil novel pathways for pioneering materials that exert a substantial impact across diverse realms of food production, storage, packaging, and quality control. Within the scope of the food industry, the scope of nanotechnology encompasses processes, storage methodologies, packaging paradigms, and safeguards to ensure the safety of consumables. Of particular note, silver nanoparticles, in addition to their commendable antibacterial efficacy, boast anti-fungal and anti-inflammatory prowess, environmental compatibility, minimal irritability and allergenicity, resilience to microbial antagonism, thermal stability, and robustness. Confronting the pressing issue of arsenic contamination within both environmental settings and the food supply is of paramount importance to preserve public health and ecological equilibrium. In response, this study introduces detection kits predicated upon silver nanoparticles, providing an expeditious and economically feasible avenue for identifying arsenic concentrations ranging from 0.5 to 3 ppm within rice. Subsequent quantification employs Hydride Atomic Absorption Spectroscopy (HG-AAS), which features a detection threshold of 0.05 ㎍/l. A salient advantage inherent in the HG-AAS methodology lies in its capacity to segregate analytes from the sample matrix, thereby significantly reducing instances of spectral interference. Importantly, the presence of arsenic in the soil beneath rice cultivation establishes a causative link to steel pipe corrosion, with potential consequences extending to food contamination-an intricate facet embedded within the broader tapestry of renewable energy, oil, and environmental pollution.

Causes and implications of increased export of frozen dumplings

  • Hye-Jung Kang;Seyoon Oh;Chanho Sohn;Hanpil Moon
    • Korean Journal of Agricultural Science
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    • v.50 no.3
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    • pp.539-549
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    • 2023
  • Domestic processed food exports might increase due to the free trade agreement (FTA) and spread of the Korean Wave, Hallyu. However, the share of the domestic raw materials in the domestic processed food industry is very low at 31.4%, which limits the spillover effect on domestic agriculture. Therefore, we selected frozen dumplings as a representative processed food whose exports are growing rapidly and conducted a multiple regression analysis to examine the effects of Hallyu and FTA variables on the frozen dumpling exports. We tried to link them to an increase in agricultural income through the expansion of demand for the domestic raw materials. This study analyzed tariff indicator as the FTA variable, cosmetics export value indicator as the Hallyu Wave variable, and other variables expected to change the trade environment such as gross domestic product (GDP) and the relative exchange rate by country as the key explanatory variables that affect changes in the trade environment. The analysis showed that the core hypothesis, the Hallyu variable and the FTA variable, have a positive impact on frozen dumpling exports. Frozen dumpling exports are expected to increase as the FTAs and the spread of Hallyu are expected to continue for the foreseeable future. Therefore, we should seek ways to increase the proportion of domestically produced ingredients in the frozen dumplings to spread the economic impact to domestic agriculture. We reviewed previous studies and determined, the price-related factors play a major role in the use of imported ingredients, and that price stability and competitiveness are essential to increase the share of the domestically produced ingredients. Based on these conclusions, we reviewed the current status of food industry-related policies and determined measures needed to expand the use of domestically produced ingredients.

A Study on the standardization of ETCS (Focused on RF) (자동요금징수시스템(ETCS) 표준화 연구(주파수방식을 중심으로))

  • Kwon, Han-Joon;Lee, Ki-Hyun;Kim, Yong-Deak
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.7 no.3
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    • pp.62-73
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    • 2008
  • In this paper, domestic standard revision plan of dynamic frequency method which is used both in unmanned automatic toll collection system and manned collection system of the express highway is presented. For such ETCS, the infrared rays (870 nm) of active frequency method and the frequency integrated method (5.8 GHz) are adopted and extended to be operated to the all around the Toll Gate. This standardization plan is based on inter connection reference model between OSI (Open System Interconnection) in process of ITS short range radio communication standardization of 5.8 GHz bandwidth to support traffic information and control system service, and the derived revision plan by starting from physical layer which support interoperability for multiple access between RSE (Road Side Equipment) and OBE (On Board Equipment), in which is categorized into physical layer, data link layer, and application layer. In case of radiation power, existing standard is divided by class1 (within 10 m) and Class2 (within 100 m) according to transmission lengthwhile it is operated with just single standard 'Class1' because of notification of Ministry of Information and Communication in 2004. In the case of the limitation value of incident power in communication area, considering operation plan of ETCS that is on actuality operation the measurements are reflected to the standard. In other wort this paper proposed the improvement standard of incident power, pseudo response in the communication area and radiated power in order to secure stability and compatibility among operator systems about the needed part on ETCS operation.

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The Quartile Deviation and the Control Chart Model of Improvement Confidence for Link Travel Speed from GPS Probe Data (사분위편차 및 관리도 모형에 의한 GPS 수집기반 구간통행속도 데이터 이상치 제거방안 연구)

  • Han, Won-Sub;Kim, Dong-Hyo;Hyun, Cheol-Seung;Lee, Ho-Won;Oh, Yong-Tae;Lee, Choul-Ki
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.7 no.6
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    • pp.21-30
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    • 2008
  • The travel speed collected by the prove-car equipped with the GPS has the problems, which are the data's stability and finding out the representative travel speed, by the influence of the traffic signal and etc. at the interrupted traffic. This study was conducted to develop the method of filtering the outlier data from the data collected by the prove-car. The method to remove the outlier data from the serial data which were collected by the prove-car was adapted to each of the quartile deviation statistics model and the management graphic statistics model. The rate of removing the outlier data by the quartile deviation method was $0{\sim}3.7%$ while the rate by the management graphic statistic methods was $0.3{\sim}7.2%$. Both methods show the low removal rate at the dawn time when the traffic is inactivity, on the other hand the remove rate is high during the daytime. However, both methods have the problem such that the threshold level for removing the outlier data was established at the low bound in the case as good as the statistics model. Therefore, it is required for the experience calibration.

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Designing and Realizing the Ground Station Receiver Low Noise Amplifier of the Next-Generation Aeronautical Surveillance System (차세대 항공 감시시스템(ADS-BES) 지상국 수신기 저잡음 증폭기 설계 및 구현)

  • Cho, Ju-Yong;Yoon, Jun-Chul;Park, Chan-Sub;Park, Hyo-Dal;Kang, Suk-Youb
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.10
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    • pp.2273-2280
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    • 2013
  • This article introduces the next-generation air surveillance system and investigates how to design of front-end low noise amplifier of the ground station receiver. In consideration of the international standard documentation and the performance of existing products, the study conducts the link budget on the entire system so that it can be competitive in terms of receive sensitivity or reliability. To obtain a proper low noise amplifier, standards of design are decided so that such factors as gain, gain flatness, and reflective loss can be optimal. In its design, the bias circuit appropriate for the characteristics of low power, low noise, or high gain was built, and according to the results of the simulation conducted after the optimal design, its gain was 16.24dB, noise factor was 0.36dB, input-output reflective loss was -18dB and -28dB each, and frequency stability was 1.11. According to the results measured after the design, its gain was 17dB, noise factor was 0.51dB, gain flatness was 0.23dB, and input-output reflective loss was -18.28dB and -24.50dB each, so the results gained were suitable for building the overall system.

A Novel Rate Control for Improving the QoE of Multimedia Streaming Service in the Internet Congestion (인터넷 혼잡상황에서 멀티미디어 스트리밍 서비스의 QoE 향상을 위한 전송률 제어기법)

  • Koo, Ja-Hon;Chung, Kwang-Sue
    • Journal of KIISE:Information Networking
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    • v.36 no.6
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    • pp.492-504
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    • 2009
  • The delivery of multimedia that efficiently adapts its bit-rate to changing network characteristics and conditions is one of the important challenging tasks in the design of today's real-time multimedia streaming systems such as IPTV, Mobile IPTV and so on. In these work, the primary focus is on network congestion, to improve network stability and inter-protocol fairness. However, these existing works have problems which do not support QoE (Quality of Experience), because they did not consider essential characteristics of contents playback such as the media continuity. In this paper, we propose a novel rate control scheme for improving the QoE of multimedia streaming service in the Internet congestion, called NCAR (Network and Client-Aware Rate control), which is based on network-aware congestion control and client-aware flow control scheme. Network-aware congestion control of the NCAR offers an improving reliability and fairness of multimedia streaming, and reduces the rate oscillation as well as keeping high link utilization. Client-aware flow control of NCAR offers a removing the media discontinuity and a suitable receiver buffer allocation, and provides a good combination of low playback delay. Simulation results demonstrate the effectiveness of our proposed schemes.

A Study on Environmental Assessment of Bikeway based on ANP Model for Sustainable Green Road (지속가능 녹색 도로 조성을 위한 ANP 모델 기반 자전거도로 환경 평가 방안)

  • Lee, Ji Hwan;Joo, Yong Jin;Park, Soo Hong
    • Spatial Information Research
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    • v.20 no.6
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    • pp.33-43
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    • 2012
  • As part of recent sustainable transport, bike has come into the spotlight as a green transport at close range to link between walking and public transit and also alterative to solve problems of existing vehicle travel. Some arguments on promotion of using bicycles have already been made in Europe, the U.S and other developed countries. To be sure, much has been written extensively in description of utilization of bike oriented by supplier, for examples, Level of Service with bike path, infrastructure such as bicycle racks and lounge etc. Therefore, our study has been differentiated in development of new evaluation model focused on level of bike user's satisfaction, comprehensively considering suitability for bikeway installation, connectivity of the public transportation system and stability in Incheon City. ANP(Analytic Network Process) analysis which is able to allow consideration of the interdependence of criteria has been hired due to multi-collinearity instead of AHP used in multi-criteria decision analysis. Last but not least, we drew bike route on a case-by-case for maintenance and improvement of its facility in Namdong-gu and Bupyeong-gu. To conclude, suggested finding has dem onstrated the validity of evaluation scheme for bikeways which is appropriate for type and purpose and ultimately this can be used to establish policy decision making for improvement of bikeway.

The DNA Repair Gene ERCC6 rs1917799 Polymorphism is Associated with Gastric Cancer Risk in Chinese

  • Liu, Jing-Wei;He, Cai-Yun;Sun, Li-Ping;Xu, Qian;Xing, Cheng-Zhong;Yuan, Yuan
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.10
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    • pp.6103-6108
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    • 2013
  • Objective: Excision repair cross-complementing group 6 (ERCC6) is a major component of the nucleotide excision repair pathway that plays an important role in maintaining genomic stability and integrity. Several recent studies suggested a link of ERCC6 polymorphisms with susceptibility to various cancers. However, the relation of ERCC6 polymorphism with gastric cancer (GC) risk remains elusive. In this sex- and age-matched case-control study including 402 GC cases and 804 cancer-free controls, we aimed to investigate the association between a potentially functional polymorphism (rs1917799 T>G) in the ERCC6 regulatory region and GC risk. Methods: The genotypes of rs1917799 were determined by Sequenom MassARRAY platform and the status of Helicobacter pylori infection was detected by enzyme-linked immunosorbent assay. Odd ratios (ORs) and 95% confidential interval (CI) were calculated by logistic regression analysis. Results: Compared with the common TT genotype, the ERCC6 rs1917799 GG genotype was associated with increased GC risk (adjusted OR=1.46, 95%CI: 1.03-2.08, P=0.035). When compared with (GT+TT) genotypes, the GG genotype also demonstrated a statistical association with increased GC risk (adjusted OR=1.38, 95%CI: 1.01-1.89, P=0.044). This was also observed for the male subpopulation (GG vs. TT: adjusted OR=1.71, 95%CI: 1.12-2.62, P=0.013; G allele vs. T allele: adjusted OR=1.32, 95%CI: 1.07-1.62, P=0.009). Genetic effects on increased GC risk tended to be enhanced by H. pylori infection, smoking and drinking, but their interaction effects on GC risk did not reach statistical significance. Conclusions: ERCC6 rs1917799 GG genotype might be associated with increased GC risk in Chinese, especially in males.