• Title/Summary/Keyword: jam

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CASPER: Congestion Aware Selection of Path with Efficient Routing in Multimedia Networks

  • Obaidat, Mohammad S.;Dhurandher, Sanjay K.;Diwakar, Khushboo
    • Journal of Information Processing Systems
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    • v.7 no.2
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    • pp.241-260
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    • 2011
  • In earlier days, most of the data carried on communication networks was textual data requiring limited bandwidth. With the rise of multimedia and network technologies, the bandwidth requirements of data have increased considerably. If a network link at any time is not able to meet the minimum bandwidth requirement of data, data transmission at that path becomes difficult, which leads to network congestion. This causes delay in data transmission and might also lead to packet drops in the network. The retransmission of these lost packets would aggravate the situation and jam the network. In this paper, we aim at providing a solution to the problem of network congestion in mobile ad hoc networks [1, 2] by designing a protocol that performs routing intelligently and minimizes the delay in data transmission. Our Objective is to move the traffic away from the shortest path obtained by a suitable shortest path calculation algorithm to a less congested path so as to minimize the number of packet drops during data transmission and to avoid unnecessary delay. For this we have proposed a protocol named as Congestion Aware Selection Of Path With Efficient Routing (CASPER). Here, a router runs the shortest path algorithm after pruning those links that violate a given set of constraints. The proposed protocol has been compared with two link state protocols namely, OSPF [3, 4] and OLSR [5, 6, 7, 8].The results achieved show that our protocol performs better in terms of network throughput and transmission delay in case of bulky data transmission.

A Study for Control of Thermal Cracking by Heat of Hydration in Subway Concrete Box Structure (지하철 콘크리트 BOX 구조물의 수화열에 의한 온도균열 제어 방안 연구)

  • Song, Suk-Jun;Yoo, Sang-Geon;Park, Ji-Woong;Kim, Eun-Kyum
    • Journal of the Korean Society for Railway
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    • v.12 no.6
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    • pp.1024-1029
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    • 2009
  • According to increase of massive concrete structures, Thermal crack done by heat of hydration have been increased in a process of the execution. In case of a subway concrete box structure, thickness of structures are almost over 1 meter, and penetrating crack by external restraint takes a bad effect on the durability with a water leakage and deterioration in especially concrete wall. A try of shortening a constructing period often occurs as subway is generally constructed according to a road to decrease a traffic jam. The research proposes executing method by skipping one block as a plan of shortening a constructing period and investigate an influence on thermal cracking control. Additionally, sensitivity analysis is accomplished by changing a height of a concrete wall, and concrete placing and air temperature met with a field condition.

Improvement of ALINEA Model Using Speed (속도를 이용한 ALINEA 모델 보완에 관한 연구)

  • Cho, Han-Seon;Lee, Jun;Lee, Ho-Won;Kim, Eun-Mi
    • Journal of Korean Society of Transportation
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    • v.26 no.5
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    • pp.73-80
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    • 2008
  • ALINEA algorithm, which is one of the best on-ramp metering algorithms, was designed to control the traffic volume from on-ramp in order to maintain the optimal occupancy rate of the detectors installed downstream of the merge area. But, the reliability of occupancy rate estimated from the loop detectors, which are used most commonly in Korea, is relatively lower than other parameters such as speed and volume. Moreover, because occupancy rate depends on the length of loop detectors and site, lots of calibration work is required whenever they are installed in order to estimate the occupancy rate. Therefore, there exists room for improvement of ALINEA algorithm because only occupancy rate having some problems is considered as a control parameter in ALINEA algorithm. Practically it is difficult to measure or perceive the occupancy rate for traffic engineers and drivers. On the other hand, speed can be good alternative which can overcome the defect induced by using occupancy. In this study, occupancy based ALINEA algorithm is converted to speed based ALINEA assuming the linear relationship between density and speed.

Inhibitory Effect of Scutellaria baicalensis Root Extract on Chemical Mediator Release and Immune Response

  • Choi, Se-Young;Choi, Dong-Kug;Park, Pyo-Jam;Choi, Wahn-Soo;Kim, Jong-Dai;Shin, Heung-Mook;Lim, Beong-Ou
    • Korean Journal of Medicinal Crop Science
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    • v.15 no.2
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    • pp.132-137
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    • 2007
  • Inhibitory effect of Scutellaria baicalensis ethanol extracts (SR) on chemical mediator release and immunoglobulin (Ig) production from Sprague-Dawley rats originated cells as type I allergic reaction was examined. SR showed concentration-dependent inhibition on basal and concanavalin A (ConA)-stimulated Ig production. In the mesenteric lymph node lymphocytes, the inhibitory effect of SR on the IgE production in the presence of Con A was stronger than these on IgA and IgG production. Moreover, tumor necrosis factor-alpha $(TNF-{\alpha})$ production-inhibiting effect of SR in the presence ConA was observed. However, SR did not affect the production of $interferon-{\gamma}$. SR also inhibited histamine release from the peritoneal exudate cells stimulated with a calcium ionophore A23187. In the case of leukotriene B4, SR markedly inhibited it at the concentration of 100 mg/ml. From these results, ethanol extracts obtained from Scutellaria baicalensis may have an anti-allergic effect on the intestinal system of rats.

The Influence of Long-term Aloe Supplement on Anti-oxidative Defenses and Cholesterol Content in Brain and Kidney of Aged Rats

  • Lim, Beong-Ou;Park, Pyo-Jam;Park, Dong-Ki;Choi, Wahn-Soo;Kim, Jong-Dai;Yu, Byung-Pal
    • Korean Journal of Medicinal Crop Science
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    • v.15 no.5
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    • pp.352-356
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    • 2007
  • The present study was investigated the anti-oxidative effects of aloe vera ingestion on brain and kidney in aged rats by monitoring several oxidative-related parameters. Male specific pathogen-free Fischer 344 rats were randomly divided into four groups of five rat each: Group A was fed test chow without aloe supplementation; Group B was fed a diet containing a 1% freeze-dried aloe filet; Group C was fed a diet containing a 1% charcoal-processed, freeze-dried aloe filet; and Group D was fed a diet containing a charcoal-processed, freeze-dried, whole leaf aloe in drinking water. Analyses of tissues were done at 4 months and 16 months of age. Results showed that a long-term intake of aloe, regardless of the preparation used, enhanced antioxidant defenses against lipid peroxidation, as indicated by reduced phosphatidylcholine hydroperoxide levels in both brain and kidney. The additional benefit of aloe intake on the anti-oxidative action was evidenced by enhanced superoxide dismutase and catalase activity in all aloe-ingested groups. Another beneficial effect of aloe shown in this study, although not an anti-oxidative parameter, was its cholesterol-lowering effect as detected in brain and kidney with significant decreases at age16 months of aloe-fed rats. Based on these findings, we conclude that a long-term dietary aloe supplementation modulated the anti-oxidative defense systems and cholesterol level.

Extracts of Artemisia princeps Pampanini Inhibit Lipopolysaccharide-induced Nitric Oxide, Cyclooxygenase-2, Prostaglandin $E_2$, and Tumor Necrosis Factor-$\alpha$ Production from Murine Macrophage RAW 264.7 Cells (강화사자발쑥의 마크로파지 RAW 264.7세포에 대한 Tumor Necrosis Factor-$\alpha$, Prostaglandin $E_2$, Cyclooxygenase-2 및 LPS 유도 Nitric Oxide 생성 저해)

  • Yun, Jun-Yong;Choi, Se-Yong;Park, Pyo-Jam;Chung, Hae-Gon;Shin, Heung-Mook;Suk, Kyoung-Ho;Lim, Beong-Ou
    • Korean Journal of Medicinal Crop Science
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    • v.16 no.5
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    • pp.326-331
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    • 2008
  • To search for immunoactive natural products exerting anti-inflammatory activity, we have evaluated the effects on the water extracts of Artemisia princeps Pampanini (APP) on lipopolysaccharide-induced nitric oxide (NO), tumor necrosis factor-$\alpha$ (TNF-$\alpha$), and prostaglandin $E_2$ ($PGE_2$) production by RAW 264.7 macrophage cell line. Our data indicate that this extract is a potent inhibitor of NO production and it also significantly decreased PGE2 and TNF-$\alpha$ production. Consistent with these results, the protein and mRNA expression level of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) was inhibited by water extracts of APP in a dose-dependent manner. These results suggest that APP may exert anti-inflammatory and analgesic effects possibly by suppressing the inducible NO synthase and COX-2 expressions.

Promoter Methylation Status of Two Novel Human Genes, UBE2Q1 and UBE2Q2, in Colorectal Cancer: a New Finding in Iranian Patients

  • Mokarram, Pooneh;Shakiba-Jam, Fatemeh;Kavousipour, Soudabeh;Sarabi, Mostafa Moradi;Seghatoleslam, Atefeh
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.18
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    • pp.8247-8252
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    • 2016
  • Background: The ubiquitin-proteasome system (UPS) degrades a variety of proteins which attach to specific signals. The ubiquitination pathway facilitates degradation of damaged proteins and regulates growth and stress responses. This pathway is altered in various cancers, including acute lymphoblastic leukemia, head and neck squamous cell carcinoma and breast cancer. Recently it has been reported that expression of newly characterized human genes, UBE2Q1 and UBE2Q2, putative members of ubiquitin-conjugating enzyme family (E2), has been also changed in colorectal cancer. Epigenetics is one of the fastest-growing areas of science and nowadays has become a central issue in biological studies of diseases. According to the lack of information about the role of epigenetic changes on gene expression profiling of UBE2Q1 and UBE2Q2, and the presence of CpG islands in the promoter of these two human genes, we decided to evaluate the promoter methylation status of these genes as a first step. Materials and Methods: The promoter methylation status of UBE2Q1 and UBE2Q2 was studied by methylation-specific PCR (MSP) in tumor samples of 60 colorectal cancer patients compared to adjacent normal tissues and 20 non-malignant controls. The frequency of the methylation for each gene was analyzed by chi-square method. Results: MSP results revealed that UBE2Q2 gene promoter were more unmethylated, while a higher level of methylated allele was observed for UBE2Q1 in tumor tissues compared to the adjacent normal tissues and the non malignant controls. Conclusions: UBE2Q1 and UBE2Q2 genes show different methylation profiles in CRC cases.

LoRa Network based Parking Dispatching System : Queuing Theory and Q-learning Approach (LoRa 망 기반의 주차 지명 시스템 : 큐잉 이론과 큐러닝 접근)

  • Cho, Youngho;Seo, Yeong Geon;Jeong, Dae-Yul
    • Journal of Digital Contents Society
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    • v.18 no.7
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    • pp.1443-1450
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    • 2017
  • The purpose of this study is to develop an intelligent parking dispatching system based on LoRa network technology. During the local festival, many tourists come into the festival site simultaneously after sunset. To handle the traffic jam and parking dispatching, many traffic management staffs are engaged in the main road to guide the cars to available parking lots. Nevertheless, the traffic problems are more serious at the peak time of festival. Such parking dispatching problems are complex and real-time traffic information dependent. We used Queuing theory to predict inbound traffics and to measure parking service performance. Q-learning algorithm is used to find fastest routes and dispatch the vehicles efficiently to the available parking lots.

Performance Analysis of Link-16 Waveform considering Frequency Remapping under PBNJ (부분대역 잡음 재밍 환경에서의 주파수 재할당을 고려한 Link-16 성능 분석)

  • Lee, Kyuman;Noh, Hongjun;Lee, Jongkwan;Lim, Jaesung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38C no.11
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    • pp.955-965
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    • 2013
  • The joint tactical information distribution system (JTIDS) is used as the communication terminal of Link-16 by the United States armed forces, north atlantic treaty organization (NATO), and other allied forces. A portion of Link-16 frequencies may be shortly remapped to other systems owing to the growing demand for frequencies, especially in civil aviation, which is witnessing a constant increase in air traffic. This will affect the performance of Link-16. Therefore, in this paper, we analyze the effect of frequency band reduction on the performance of Link-16 waveform under partial-band noise jamming with Nakagami fading, via simulation and numerical analysis. The multi-net and anti-jamming performance of Link-16 with frequency remapping is compared with that of conventional Link-16 systems. The results show that the performance of Link-16 waveform is degraded with the reduction in frequencies. Nonetheless, Link-16 retains its jam resistance, and it can support multiple users in the same time slots.

A Suggestion on the Traffic Flagger System in Japan (일본 교통유도 경비제도의 시사점)

  • Kim, Il-Gon
    • Proceedings of the Korea Contents Association Conference
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    • 2010.05a
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    • pp.200-203
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    • 2010
  • The obstructive factors of the smoothly running traffic are street improvement, major commercial buildings like department stores, the large markets, the stadiums, the concert buildings, a lot of steady cars for using parking lot. The accident of cost many lives and traffic congestion from these factors cause the result that it enables to pay the enormous expenditure socially and financially. For solving these problems, Japan adopts the Traffic Flagger System in 1972. This task has the effects of improving traffic flow in the traffic jam and mitigating risk of car accidents as leading pedestrians and vehicles thereby the task carries into effect in the area where the accident took place. Moreover, this security task is rapid growth after adopting and 59.6%(5,317) of the whole security company 8,924 in Japan based on December 2009 registered as the traffic leading security business. While South Korea is demanded of the measures about obstructive factors of the smoothly running traffic, it represents the limitation of the system and the safety management. Thus the current study suggests the we will analyze South Korea's actual condition and then discuss the law and education system for a realizable plan reached the public-Private cooperation for adopting Japan's Traffic Leading Security System.

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