• Title/Summary/Keyword: time-delay effect

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Design and Implementation of A Multi-Point Multimedia Conference System Using IP Grouping (IP 그룹화를 이용한 다자간 멀티미디어 회의시스템의 설계 및 구현)

  • Sung Baek-Kyon;Seong Dong-Su;Lee Keon-Bae;Hyun Don-Whan
    • Journal of Korea Multimedia Society
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    • v.8 no.7
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    • pp.1012-1021
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    • 2005
  • This paper describes the design and implementation of an efficient multi-point multimedia conference system using IP grouping. Existing multi-point multimedia conference systems are difficult for multi-user to perform efficient cooperation due to bandwidth limitation for data transmission of video, audio and documentation. In the case that multi-user uses limited bandwidth, smooth cooperation does not accomplish due to transmission delay for the real-time transmission of image and speech data. A hybrid transfer method which is mixed with distributed and centralized methods is used for smooth cooperation, and the network bandwidth is reduced by forming multi-user conference systems of IP grouping in this paper. Also, adaptive image frame variations are used to solve bottleneck effect according to the number of users. An efficient multi-user conference system is designed to support audio quality.

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The Improvement Plans for Material Flow and Productivity Improvement of Low-e Double Glazing on Site (Low-e 복층유리의 현장 내 물류흐름 파악 및 생산성 향상을 위한 개선안 방향)

  • Lee Sang-Hyuk;Lim Myung-Bok;Lee Jae-Sung;Kim Chang-Duk
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.341-344
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    • 2003
  • There are many problems in management of high-rise building construction performed in downtown area due to limited spaces and equipments for increasing kinds and quantities of material. By these restrictions, problems such as increase of construction cost. delay of construction period, decrease of productivity, occurrence of accident are caused. Recently, studies on JIT concept have focused on construction materials as a solution for the problems. But, studies about finishing material are insufficient yet. Accordingly, this study suggests flowing of current material management, JIT management effect, and development direction of lifting-up and procurement system with Low-emissivity double Glazing, among of main finishing materials.

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The Performance Improvement using Rate Control in End-to-End Network Systems (종단간 네트워크 시스템에서 승인 압축 비율 제어를 이용한 TCP 성능 개선)

  • Kim, Gwang-Jun;Yoon, Chan-Ho;Kim, Chun-Suk
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.1
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    • pp.45-57
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    • 2005
  • In this paper, we extend the performance of bidirectional TCP connection over end-to-end network that uses transfer rate-based flow and congestion control. The sharing of a common buffer by TCP packets and acknowledgement has been known to result in an effect called ack compression, where acks of a connection arrive at the source bunched together, resulting in unfairness and degraded throughput. The degradation in throughput due to bidirectional traffic can be significant. Even in the simple case of symmetrical connections with adequate window size, the connection efficiency is improved about 20% for three levels of background traffic 2.5Mbps, 5.0Mbps and 7.5Mbps. Otherwise, the throughput of jitter is reduced about 50% because round trip delay time is smaller between source node and destination node. Also, we show that throughput curve is improved with connection rate algorithm which is proposed for TCP congetion avoidance as a function of aggressiveness threshold for three levels of background traffic 2.5Mbps, 5Mbps and 7.5Mbps. By analyzing the periodic bursty behavior of the source IP queue, we derive estimated for the maximum queue size and arrive at a simple predictor for the degraded throughput, applicable for relatively general situations.

Effects of the ROM Dance on Cognitive Function, Behavioral and Psychological Symptoms of Dementia(BPSD) in Using Wheelchair Senior in Nursing Home (요양원에서 휠체어를 이용하고 있는 노인에게 ROM Dance가 인지기능과 신경정신행동에 미치는 효과)

  • Song, Byung-Nam
    • The Journal of Korean society of community based occupational therapy
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    • v.2 no.1
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    • pp.37-47
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    • 2012
  • Objective : The purpose of this study was to identify Effects of the ROM dance on cognitive function, neuropsychiatric in using wheelchair senior in nursing home. Methods : The subjects of the experimental group were 15 seniors using wheelchair who attended an ROM dance program in a nursing home. It was carried out for 18 weeks from Mar. 2010. to August. 2010. The evaluation tools used for the presented study were the Mini-Mental Status Exam-Korean(MMSE-K) and Neuropsychiatric Inventory-Questionaire (NPI-Q). Results : In the terms of cognitive function there was no significant defference between the mean pre/post test. but the factor(orientation of time) of MMSE-K and the factors 2 (sleep/nighttime behavios, apathy/indefference) of NPI-Q was significant improvement. Conclusion : In this study, the ROM dance program was effective in improving cognitive function and neuropsychiatric in seniors using wheelchair. also ROM dance program was decreasing and regression delay effect in cognitive and neuropsychiatric.

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TCP Congestion Control of Transfer Rate-based in End-to-End Network Systems (종단간 네트워크 시스템에서 전송율 기반 TCP 혼잡제어)

  • Bae, Young-Geun;Yoon, Chan-Ho;Kim, Gwang-Jun
    • The Journal of the Korea institute of electronic communication sciences
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    • v.1 no.2
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    • pp.102-109
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    • 2006
  • In this paper, we improve the performance of bidirectional TCP connection over end-to-end network that uses transfer rate-based flow and congestion control. The sharing of a common buffer by TCP packets and acknowledgement has been known to result in an effect called ack compression, where acks of a connection arrive at the source bunched together, resulting in unfairness and degraded throughput. The degradation in throughput due to bidirectional traffic can be significant. For example, even in the simple case of symmetrical connections with adequate window size, the connection efficiency is improved about 20% for three levels of background traffic 2.5Mbps, 5.0Mbps and 7.5Mbps. Otherwise, the throughput of jitter is reduced about 50% because round trip delay time is smaller between source node and destination node. Also, we show that throughput curve is improved with connection rate algorithm which is proposed for TCP congestion avoidance as a function of aggressiveness threshold for three levels of background traffic 2.5Mbps, 5Mbps and 7.5Mbps.

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STC2 is upregulated in hepatocellular carcinoma and promotes cell proliferation and migration in vitro

  • Wang, Haixiao;Wu, Kuangjie;Sun, Yuan;Li, Yandong;Wu, Mingyu;Qiao, Qian;Wei, Yuanjiang;Han, Ze-Guang;Cai, Bing
    • BMB Reports
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    • v.45 no.11
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    • pp.629-634
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    • 2012
  • The human glycoprotein, stanniocalcin 2 (STC2) plays multiple roles in several tumor types, however, its function and clinical significance in hepatocellular carcinoma (HCC) remain unclear. In this study, we detected STC2 expression by quantitative real-time PCR and found STC2 was upregulated in HCC tissues, correlated with tumor size and multiplicity of HCC. Ectopic expression of STC2 markedly promoted HCC cell proliferation and colony formation, while silencing of endogenous STC2 resulted in a reduced cell growth by cell cycle delay in G0/G1 phase. Western blot analysis demonstrated that STC2 could regulate the expression of cyclin D1 and activate extracellular signal-regulated kinase 1/2 (ERK1/2) in a dominant-positive manner. Transwell chamber assay also indicated altered patterns of STC2 expression had an important effect on cell migration. Our findings suggest that STC2 functions as a potential oncoprotein in the development and progression of HCC as well as a promising molecular target for HCC therapy.

Application of artificial neural networks to predict total dissolved solids in the river Zayanderud, Iran

  • Gholamreza, Asadollahfardi;Afshin, Meshkat-Dini;Shiva, Homayoun Aria;Nasrin, Roohani
    • Environmental Engineering Research
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    • v.21 no.4
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    • pp.333-340
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    • 2016
  • An Artificial Neural Network including a Radial Basis Function (RBF) and a Time Delay Neural Network (TDNN) was used to predict total dissolved solid (TDS) in the river Zayanderud. Water quality parameters in the river for ten years, 2001-2010, were prepared from data monitored by the Isfahan Regional Water Authority. A factor analysis was applied to select the inputs of water quality parameters, which obtained total hardness, bicarbonate, chloride and calcium. Input data to the neural networks were pH, $Na^+$, $Mg^{2+}$, Carbonate ($CO{_3}^{-2}$), $HCO{_3}^{-1}$, $Cl^-$, $Ca^{2+}$ and Total hardness. For learning process 5-fold cross validation were applied. In the best situation, the TDNN contained 2 hidden layers of 15 neurons in each of the layers and the RBF had one hidden layer with 100 neurons. The Mean Squared Error and the Mean Bias Error for the TDNN during the training process were 0.0006 and 0.0603 and for the RBF neural network the mentioned errors were 0.0001 and 0.0006, respectively. In the RBF, the coefficient of determination ($R^2$) and the index of agreement (IA) between the observed data and predicted data were 0.997 and 0.999, respectively. In the TDNN, the $R^2$ and the IA between the actual and predicted data were 0.957 and 0.985, respectively. The results of sensitivity illustrated that $Ca^{2+}$ and $SO{_4}^{2-}$ parameters had the highest effect on the TDS prediction.

The Effect of Intraperitoneal Instillation and Trocar Site Infiltration of 0.25% Levobupivacaine on the Postoperative Pain after Performing Laparoscopic Cholecystectomy under Remifentanil Based Anesthesia (Remifentanil을 이용한 전신마취하에 시행된 복강경 담낭절제술에서 0.25% Levobupivacaine의 트로카 부위침윤과 복강 내 점적주입이 수술 후 진통에 미치는 효과)

  • Lee, Cheol;Song, Yoon Kang
    • The Korean Journal of Pain
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    • v.21 no.1
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    • pp.44-50
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    • 2008
  • Background: The use of regional local anesthetics or opioids during laparoscopic cholecystectomy (LC), in combination with general anesthesia, has been investigated in several interventional studies. Methods: We studied a total of 240 (n = 60, each) patients who were undergoing LC, and they received local infiltration and intraperitoneal instillation with normal saline or 0.25% levobupivacaine 60 ml. Group R (S) received infiltration of normal saline 20 ml before incision and at the end of surgery and then 40 ml intraperitoneal instillation after removal of the gall bladder under remifentanil-based anesthesia. Group R (L) received 0.25% levobupivacaine instead of normal saline in the same method like group R (S). Group S (S) received the same method as group R (S) under sevoflurane based anesthesia in place of remifentanil. Group S (L) received 0.25% levobupivacaine instead of normal saline with the same method as group S (S). Pain was assessed on a visual analog scale at 1, 6, 12 and 24 hours after operation. Results: The pain intensity of Group R (L) was significantly lower than that of group R (S), and the the incisional pain of group S (L) was significantly lower than that of group S (S) in the first six hours. The time delay to first operative analgesics in group R (S) and group S (S) was significantly shorter than that of group R (L) and group S (L). Conclusions: Infiltration and instillation of levobupivacaine reduced the postoperative pain and remifentanil did not increase the pain severity and opioid requirement when performing the LC.

A new approach to quantify paraquat intoxication from postmortem blood sample by using 1H qNMR method

  • Hong, Ran Seon;Cho, Hwang Eui;Kim, Dong Woo;Woo, Sang Hee;Choe, Sanggil;Kim, Suncheun;Hong, Jin Tae;Moon, Dong Cheul
    • Journal of the Korean Magnetic Resonance Society
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    • v.17 no.1
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    • pp.40-46
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    • 2013
  • For a case study of suspected paraquat intoxication, we developed a simple and rapid method of $^1H$ qNMR to determine the mili-molar amount of paraquat in postmortem blood samples. There were no interfering signals from endogenous compounds in the chemical shift of paraquat and diquat (internal standard). The amount of sample used ranged from 0.25 mM to 10.0 mM. Diquat, which has similar physicochemical properties with paraquat, was chosen as an internal standard. The NMR experimental conditions, relaxation delay time and CPMG spin-echo pulse sequence were optimized. The developed method was validated in terms of specificity, accuracy, precision, matrix effect, recovery, limit of detection (LOD), and low limit of quantification (LLOQ). The proposed qNMR method provided a simple and rapid assay for the identification and quantification of the quaternary ammonium herbicide, "paraquat" in postmortem blood samples. This method was tested by using the blood from the heart of a man who was intoxicated with paraquat. In this particular case, the level of paraquat was 1.07 mM in the blood. For the determination of quaternary ammonium herbicides, qNMR could also be used to provide a better understanding of the currently available techniques.

Analysis of the GPS Signal Generator for the Live GPS Signal Synchronization (Live GPS L1과 동기된 항법신호 생성 분석)

  • Kim, Taehee;Sin, Cheonsig;Kim, Jaehoon
    • Journal of Satellite, Information and Communications
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    • v.10 no.1
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    • pp.71-76
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    • 2015
  • In this paper, we developed the hardware GPS signal generator for generating a satellite navigation signal synchronized with Live GPS signal signals and analyzed the performance of signal genterator thorough the experiment For a hardware implementation of the GPS navigation signal synchronous generator, the GPS module may receive a GPS signal in order to generate the same signal as the operation that is transmitted from the current GPS satellite and the synchronized time information and the GPS satellites using the Novatel Inc. OEMStar.In. For generating the GPS synchronization signal, the GPS navigation signal generator was adjusted to a reference clock using the GPS clock synchronous information provided by the GPS receiving module and GPS signals also generated in consideration of the delay of the internal hardware of the generator. In this paper, we analyzed the effect of the receiver via the signal switching between Live GPS signal and generates a signal to measure the performance of the GPS navigation synchronization signal generator. It was confirmed that by the seamless operation of the signal even the moment that the switching of the generated signal from Live GPS signal has occurred through experimentation.