• Title/Summary/Keyword: low-order control

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Uncertainty Management on Human Intrusion Scenario Assessment of the Near Surface Disposal Facility for Low and Intermediate-Level Radioactive Waste: Comparative Analysis of RESRAD and GENII (중저준위방사성폐기물 표층처분시설의 인간침입 시나리오 평가에 대한 불확실성 관리: RESRAD와 GENII의 비교분석)

  • Kim, Minseong;Hong, Sung-Wook;Park, Jin Beak
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.15 no.4
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    • pp.369-380
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    • 2017
  • In order to manage the uncertainty about the evaluation and analysis of the human intrusion scenario of the Gyeongju Low and Intermediate Level Radioactive Waste(LILW) disposal facility, the calculation result by the GENII code was assessed using the RESRAD code, which was developed to evaluate the radiation effects of contaminated soil. The post-drilling scenario was selected as a human intrusion scenario into the near-surface disposal facility to analyze the uncertainty of the modeling by identifying any limitations in the simulation of each code and comparing the evaluation results under the same input data conditions. The results revealed a difference in the migration of some nuclides between the codes, but confirmed that the dose trends at the end of the post-closure control period were similar for all exposure pathways. Based on the results of the dose evaluation predicted by RESRAD, sensitivity analysis on the input factors was performed and major input factors were derived. The uncertainty of the modeling results and the input factors were analyzed and the reliability of the safety evaluation results was confirmed. The results of this study can be applied to the implementation 'Safety Case Program' for the Gyeongju LILW disposal facility.

The Water Circulation Improvement of Apartment Complex by applying LID Technologies - Focused on the Application of Infiltration Facilities - (LID 기술 적용을 통한 공동주택단지 물순환 개선 연구 - 침투시설 적용을 중심으로 -)

  • Suh, Joo-Hwan;Lee, In-Kyu
    • Journal of the Korean Institute of Landscape Architecture
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    • v.41 no.5
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    • pp.68-77
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    • 2013
  • Change in the Global Climate causes flood, drought, heavy snow, and rainfall patterns in the Korean Peninsula. A variety of alternatives related to climate change are considered. The foreign researchers are interested in Low Impact Development(LID); the utilization of water resources and eco friendly development, over 10 years ago. The research and development of related technology has been advanced to apply LID techniques in order to develop several projects in the country. However, sharing of technology or system that can be used easily in the private sector is insufficient. The performance of the elements of LID Technology has not been fully agreed. LID elements of this technology are easy to apply to Apartment complex. The elements are classified technology. The infiltration of elements performs the functions of apartment complex landscaping space technology applied to the target. The water cycle simulation(SWMM 5.0) and technology the implementation of the effectiveness is also verified. For this purpose, three different places in apartment complex to target by SWMM5.0 U.S. EPA conducted utilizing simulated rainfall and applying LID techniques before and after the simulated water cycle (infiltration, surface evaporation, and surface runoff) were conducted. The importance of green space in the LID techniques of quantitative and qualitative storm water control as well as the role of Apartment Housing is to promote Amenity. Remember that the physical limitations of apartment complex and smooth water circulation system for the application of LID integrated management techniques should be applied. To this end, landscapes, architecture, civil engineering, environmental experts for technical consilience between the Low Impact Development efforts are required.

MAC Scheduling Algorithm for Efficient Management of Wireless Resources in Bluetooth Systems (블루투스 시스템에서의 효율적 무선자원관리를 위한 MAC 스케쥴링 기법)

  • 주양익;권오석;오종수;김용석;이태진;엄두섭;차균현
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.9A
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    • pp.702-709
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    • 2003
  • In this paper, we propose an efficient and QoS-aware MAC scheduling algorithm for Bluetooth, which considers both throughput and delay performance of each Master-Slave pair in scheduling decisions, and thus, attempts to maximize overall performance. The proposed algorithm, MTDPP (Modified Throughput-Delay Priority Policy), makes up for the drawbacks of T-D PP (Throughput-Delay Priority Policy) proposed in [6] and improves the performance. Since Bluetooth employs a master-driven TDD based scheduling algorithm, which is basically operated with the Round Robin policy, many slots may be wasted by POLL or NULL packets when there is no data waiting for transmission in queues. To overcome this link wastage problem, several algorithms have been proposed. Among them, queue state-based priority policy and low power mode-based algorithm can perform with high throughput and reasonable fairness. However, their performances may depend on traffic characteristics, i.e., static or dynamic, and they require additional computational and signaling overheads. In order to tackle such problems, we propose a new scheduling algorithm. Performance of our proposed algorithm is evaluated with respect to throughput and delay. Simulation results show that overall performances can be improved by selecting suitable parameters of our algorithm.

A Study on the Behavior Characteristics of Soft Clay Ground by C.G.S Method (C.G.S공법을 적용한 연약점토지반에서의 거동특성에 관한 연구)

  • 천병식;여유현
    • Journal of the Korean Geotechnical Society
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    • v.19 no.6
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    • pp.307-323
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    • 2003
  • In this study the pilot test of C.G.S (Compaction Grouting System) as injection method by low slump mortar was performed and the results were analyzed in order to find out the application of this method to the soft ground and the effect of settlement restraint. The site for pilot test is adjacent to apartments supported by pile foundations. Sand drain method was performed previously as countermeasures against settlement, but settlement occurs continuously because this ground is very soft. Site investigations such as SPT, CPT and vane shear test were performed to determine the characteristics of ground improvement after the installation of C.G.S. Field measurements were performed on purpose to find out the displacement of ground during the installation of C.G.S. From the results of this study, C.G.S method can be optimized by the control of radius, space, depth, injection material and injection pressure. C.G.S improves soft ground with radial consolidation of adjacent soft ground. Considering that increase of N value to about 3, C.G.S can be considered as an effective method to increase the bearing capacity as well as constrain the settlement of soft ground. It is also expected to be economic and effective in the improvement of ground when it is used in applicable sites.

A Medium Power Single-Pole-Double-Throw MMIC Switch for IEEE 802.11a WLAN Applications (IEEE 802.11a 무선랜용 중간전력 SPDT 초고주차단일집적회로 스위치 제작 및 특성)

  • Mun JaeKyoung;Kim Haecheon;Park Chong-Ook
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.10A
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    • pp.965-970
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    • 2005
  • In this paper, SPDT Tx/Rx MMIC switch applicable to IEEE 802.11a WLAN systems is designed and fabricated using a specific designed epitaxial layered pHEMT wafer and ETRI's $0.5{\mu}m$ pHEMT switch process. The SPDT switch exhibits a low insertion loss of 0.68dB, high isolation of 35.64dB, return loss of 13.4dB, power transfer capability of 25dBm, and 3rd order intercept point of 42dBm at frequency of 5.8GHz and control voltage of 0/-3V. The comparison of the measured performances with commercial products based on the GaAs pHEMT technology for low voltage operating at ${\pm}$ 3V/0V shows that the return loss is somewhat inferior to the commercial products and insertion loss is compatible with each other however, isolation characteristics are much better than in conventional chips. Based on these performances, we can conclude that the developed SPDT switch MMIC has an enough potential for IEEE802.11a standard 5 GHz-band wireless LAN applications.

Plasma Etching Characteristics of Sapphire Substrate using $BCl_3$-based Inductively Coupled Plasma ($BCl_3$ 계열 유도결합 플라즈마를 이용한 사파이어 기판의 식각 특성)

  • Kim, Dong-Pyo;Woo, Jong-Chang;Um, Doo-Seng;Yang, Xue;Kim, Chang-Il
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.363-363
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    • 2008
  • The development of dry etching process for sapphire wafer with plasma has been key issues for the opto-electric devices. The challenges are increasing control and obtaining low plasma induced-damage because an unwanted scattering of radiation is caused by the spatial disorder of pattern and variation of surface roughness. The plasma-induced damages during plasma etching process can be classified as impurity contamination of residual etch products or bonding disruption in lattice due to charged particle bombardment. Therefor, fine pattern technology with low damaged etching process and high etch rate are urgently needed. Until now, there are a lot of reports on the etching of sapphire wafer with using $Cl_2$/Ar, $BCl_3$/Ar, HBr/Ar and so on [1]. However, the etch behavior of sapphire wafer have investigated with variation of only one parameter while other parameters are fixed. In this study, we investigated the effect of pressure and other parameters on the etch rate and the selectivity. We selected $BCl_3$ as an etch ant because $BCl_3$ plasmas are widely used in etching process of oxide materials. In plasma, the $BCl_3$ molecule can be dissociated into B radical, $B^+$ ion, Cl radical and $Cl^+$ ion. However, the $BCl_3$ molecule can be dissociated into B radical or $B^+$ ion easier than Cl radical or $Cl^+$ ion. First, we evaluated the etch behaviors of sapphire wafer in $BCl_3$/additive gases (Ar, $N_2,Cl_2$) gases. The behavior of etch rate of sapphire substrate was monitored as a function of additive gas ratio to $BCl_3$ based plasma, total flow rate, r.f. power, d.c. bias under different pressures of 5 mTorr, 10 mTorr, 20 mTorr and 30 mTorr. The etch rates of sapphire wafer, $SiO_2$ and PR were measured with using alpha step surface profiler. In order to understand the changes of radicals, volume density of Cl, B radical and BCl molecule were investigated with optical emission spectroscopy (OES). The chemical states of $Al_2O_3$ thin films were studied with energy dispersive X-ray (EDX) and depth profile anlysis of auger electron spectroscopy (AES). The enhancement of sapphire substrate can be explained by the reactive ion etching mechanism with the competition of the formation of volatile $AlCl_3$, $Al_2Cl_6$ or $BOCl_3$ and the sputter effect by energetic ions.

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Performance Evaluation and Offset Time Decision for Supporting Differential Multiple Services in Optical Burst Switched Networks (광 버스트 교환 망에서 차등적 다중 서비스 제공을 위한 offset 시간 결정 및 성능 평가)

  • So W.H.;im Y.C.K
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.41 no.1
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    • pp.1-12
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    • 2004
  • In this paper, we take advantage of the characteristics of optical burst switching (OBS) to support service-differentiation in optical networks. With the offset time between control packet and burst data, the proposed scheme uses different offset time of each service class. As contrasted with the Previous method, in which the high Priority service use only long offset time, it derives the burst loss rate as a QoS parameter in consideration of conservation law and given service-differential ratios and decides a reasonable offset time for this QoS finally Firstly proposed method classifies services into one of high or low class and is an algorithm deciding the offset time for supporting the required QoS of high class. In order to consider the multi-classes environment, we expand the analysis method of first algorithm and propose the second algorithm. It divides services into one of high or low group according to their burst loss rate and decides the offset time for high group, and lastly cumulates the offset time of each class. The proposed algorithms are evaluated through simulation. The result of simulation is compared with that of analysis to verify the proposed scheme.

Lack of Association of the NPAS2 Gene Ala394Thr Polymorphism (rs2305160:G>A) with Risk of Chronic Lymphocytic Leukemia

  • Rana, Sobia;Shahid, Adeela;Ullah, Hafeez;Mahmood, Saqib
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.17
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    • pp.7169-7174
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    • 2014
  • Background: NPAS2 is a product of the circadian clock gene. It acts as a putative tumor suppressor by playing an important role in DNA damage responses, cell cycle control and apoptosis. Chronic lymphocytic leukemia (CLL) appears to be an apoptosis related disorder and alteration in the NPAS2 gene might therefore be directly involved in the etiology of CLL. Here, the Ala394Thr polymorphism (rs2305160:G>A) in the NPAS2 gene was genotyped and melatonin concentrations were measured in a total of seventy-four individuals, including thirty-seven CLL cases and an equal number of age- and sex-matched healthy controls in order to examine the effect of NPAS2 polymorphism and melatonin concentrations on CLL risk in a Pakistani population. Materials and Methods: Genotyping of rs2305160:G>A polymorphism at NPAS2 locus was carried out by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). Melatonin concentrations were determined by enzyme linked immunosorbent assay (ELISA). Statistical analysis was performed using Statistical Package for Social Sciences software. Results: Our results demonstrated no association of the variant Thr genotypes (Ala/Thr and Thr/Thr) with risk of CLL. Similarly, no association of rs2305160 with CLL was observed in either females or males after stratification of study population on a gender basis. Moreover, when the subjects with CLL were further stratified into shift-workers and non-shift-workers, no association of rs2305160 with CLL was seen in either case. However, significantly low serum melatonin levels were observed in CLL patients as compared to healthy subjects (p<0.05). Also, lower melatonin levels were seen in shift-workers as compared to non-shift-workers (p<0.05). There was no significant difference (p>0.05) in the melatonin levels across NPAS2 genotypes in all subjects, subjects with CLL who were either shift workers or non-shift-workers. General Linear Model (GLM) univariate analysis revealed no significant association (p>0.05) of the rs2305160 polymorphism of the NPAS2 gene with melatonin levels in any of the groups. Conclusions: While low melatonin levels and shift-work can be considered as one of the risk factors for CLL, the NPAS2 rs2305160 polymorphism does not appear to have any association with risk of CLL in our Pakistani population.

Heart Rate Variability in Patients with Coronary Artery Disease (관상동맥질환 환자의 심박동변이도)

  • Kim Wuon-Shik;Bae Jang-Ho;Choi Hyoung-Min;Lee Sang-Tae
    • Science of Emotion and Sensibility
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    • v.8 no.2
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    • pp.95-101
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    • 2005
  • This study is based on previous information regarding reduced cardiac vagal activity in patients with coronary artery disease(CAD), on reduced variance(SDNN : standard deviation of all normal RR intervals), low-frequency power(LF), and the complexity of heart rate variability(HRV) in patients with chronic heart failure(CHF), and on the normalized high-frequency power of HRV is the highest in the right lateral decubitus position among 3 recumbent postures in patients with CAD, However, nothing is known about the nonlinear dynamics of HRV for the 3 recumbent postures in patients with CAD. To investigate the linear and non-linear characteristics of HRV in patients with CAD, 29 patients as CAD group and 23 patients as control group were studied. Electrocardiogram(ECG) with lead II channel was measured on these patients for 3 recumbent postures in random order. The HRV from ECG was analyzed with linear method(for time and frequency domains) and nonlinear method. The lower the high-frequency power in normalized unit(nHF) in the supine or left lateral decubitous position, the higher the increase in nHF when the position was changed from supine or left lateral decubitous to right lateral decubitous. Among the 3 recumbent postures in patients with severe CAD, the right lateral decubitus position was observed to induce the highest vagal modulation, the lowest sympathetic modulation, and the highest complexity of human physiology system.

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Feasibility of Cheonghju Brewing with Wild Type Yeast Strains from Nuruks (누룩으로부터 분리한 Wild Type 효모의 청주(淸酒)제조 가능성에 관한 연구)

  • Kim Hye-Ryun;Baek Seung-Hee;Seo Min-Jae;Ahn Byung-Hak
    • Microbiology and Biotechnology Letters
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    • v.34 no.3
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    • pp.244-249
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    • 2006
  • In order to select the best strains to have the feasibility of Cheonghju brewing, 10 wild type yeast strains from 300 different types of Nuruk were investigated on their ethanol resistance, resistance to glucose and flocculation. The amounts of alcohol, organic acids, and volatile compounds, Brix, pH were also examined for the alcoholic beverages made with the 10 selected strains. Almost all strains showed alcohol production activities in the medium containing 18%(v/v) ethanol and 29%(w/v) glucose. The strains 90-2 showed a higher flocculation activity than other strains. Strains 54-3, 90-2 and 91-5 produced more alcohol than control strain (7.42%(w/w)) when fermented with wild type yeast strains. In addition, alcoholic beverages containing low acetic acid also showed low levels of total acidity. GC/MS analysis of the product showed 4 alcohols, 11 esters and 1 acid as volatile compounds. Selected strains were tentatively identified as Phichia sydowiorum (91-5), Zygosaccharomyces cidri (192-2 and 271-4), and as Saccharomyces cerevisiae (18-2, 54-3, 90-2, 91-2, 98-2, 99-5 and 272-7) by BIIOLOG method.