• Title/Summary/Keyword: duplex

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Application Scenarios of Nautical Ad-hoc Network in Wireless Mobile Communication under Maritime Environment (해상 환경에서의 무선 이동 통신을 위한 선박용 Ad-hoc 네트워크 운용 시나리오)

  • Kim, Young-Bum;Chang, Kyung-Hi;Yun, Chang-Ho;Park, Jong-Won;Lim, Yong-Kon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.10
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    • pp.2097-2104
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    • 2009
  • In terrestrial communications, high data rate transmission can be achieved by splitting the coverage area into small cells through base stations and reusing the resource efficiently. However, the geographical features of maritime communications require the long transmission range, and it is not practical to install base station on the sea to set up the similar deployment as the terrestrial communications, so MF/HF band modem with low data rate are currently utilized for maritime communications. And the expensive satellite communication via Inmarsat is the conventional solution for the high data rate transmission on the sea. To reduce the cost, Ad-hoc network is proposed to apply on the sea, which requires no base station for the peer-to-peer communications. In this paper, we denominate this maritime environment specific Ad-hoc network as Nautical Ad-hoc Network (NANET). Furthermore, the deployment scenario for the NANET, and the analysis on multiple access and duplexing schemes for the NANET are discussed in this paper, which serves as the cornerstone for the further NANET research and development.

Traumatic Pseudoaneurysm of the Superficial Temporal Artery: Two Cases Report (수상 후 천측두동맥에 발생한 가성동맥류의 치료 2례)

  • Kim, Youn Hwan;Hwang, Won Jung;Song, Soon-Young
    • Archives of Plastic Surgery
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    • v.34 no.1
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    • pp.115-118
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    • 2007
  • Purpose: It is even less common traumatic pseudoaneurysm of the superficial temporal artery and rare with fewer than 200 cases reported in the recent literature. Most common causes of traumatic pseudoaneurysm is sequelae of blunt, penetrating, or iatrogenic surgical trauma. The diagnosis is based on physical findings and can be confirmed by duplex ultrasonogram, computed tomography, and angiography. Surgical resection, percutaneous embolization and conservative treatment have all been used to treat pseudoaneurysm. However recently, non invasive technique like percutaneous thrombin injection under ultrasonographic guidance has been done rather than surgical ligation. In this report, we proposed the several treatment options such as conservative treatment, thrombin injection, and surgical ligation according to the multifarous conditions of pseudoaneurysm, patient, and causes. Methods: We describe two cases of traumatic pseudoaneurysm of superficial temporal artery in which CT angiography was effective in diagnosis and characterization. One is chronic pseudoaneurysm after traffic accident, which is fusiform shape and small size. Since the patient prefered it, we proposed percutaneous thrombin injection first. But we recognize that this method failed, we used surgical ligation according to information of CT angiographic findings. The other is acute pseudoaneurysm after blunt trauma, which is large size accompanying large hematoma. So we proposed compressive dressing and aspiration of hematoma. Results: Two cases were well treated with no recurrence or complication. Conclusion: In conclusion, when selecting a treatment options, followings should be considered: pseudoaneurysm in CT angiography, chronicity, cause, and patient's preference.

Internal Amplification Control for a Cryptosporidium Diagnostic PCR: Construction and Clinical Evaluation

  • Hawash, Yousry;Ghonaim, M.M.;Al-Hazmi, Ayman S.
    • Parasites, Hosts and Diseases
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    • v.53 no.2
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    • pp.147-154
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    • 2015
  • Various constituents in clinical specimens, particularly feces, can inhibit the PCR assay and lead to false-negative results. To ensure that negative results of a diagnostic PCR assay are true, it should be properly monitored by an inhibition control. In this study, a cloning vector harboring a modified target DNA sequence (${\approx}375bp$) was constructed to be used as a competitive internal amplification control (IAC) for a conventional PCR assay that detects ${\approx}550bp$ of the Cryptosporidium oocyst wall protein (COWP) gene sequence in human feces. Modification of the native PCR target was carried out using a new approach comprising inverse PCR and restriction digestion techniques. IAC was included in the assay, with the estimated optimum concentration of 1 fg per reaction, as duplex PCR. When applied on fecal samples spiked with variable oocysts counts, ${\approx}2$ oocysts were theoretically enough for detection. When applied on 25 Cryptosporidium-positive fecal samples of various infection intensities, both targets were clearly detected with minimal competition noticed in 2-3 samples. Importantly, both the analytical and the diagnostic sensitivities of the PCR assay were not altered with integration of IAC into the reactions. When tried on 180 randomly collected fecal samples, 159 were Cryptosporidium-negatives. Although the native target DNA was absent, the IAC amplicon was obviously detected on gel of all the Cryptosporidium-negative samples. These results imply that running of the diagnostic PCR, inspired with the previously developed DNA extraction protocol and the constructed IAC, represents a useful tool for Cryptosporidium detection in human feces.

A study on cross sectional characteristics and available area for using the lower space in TBM road tunnels (TBM 도로터널의 단면특성 및 하부공간 활용을 위한 유효면적 검토)

  • Kim, Hyun-Soo;Kim, Hong-Moon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.14 no.2
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    • pp.141-157
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    • 2012
  • For the application TBM tunneling method, Both tunnel design standard and case study designed & constructed in domestic and foreign have been conducted. According to the study, the number of lane and inner shape (single or duplex) vary depending on the volume of traffic. Also extra space located in the top and bottom of tunnel is used for a multipurpose such as ventilation, disaster prevention, maintenance and administration. To find area ratio according to the components of road TBM tunnel, a standard section was considered as a two-lane road. Then, the analysis of area ratio of this section which consists of components for clearance, extra space in upper and lower tunnel was carried on two widths of shoulder. In addition, after a structural analysis, a thickness requirement of lower slab which is essential for road tunnel was derived on a few supporting types. Through correlation analysis, the ranges of available cross-sectional area between slab thickness and lower extra space of the tunnel was presented.

Effect of Roughness and Densification of Precalendered Sheet on Surface Roughening

  • Youn, Hye-Jung;Lee, Hak-Lae;Chin, Seong-Min;Lee, Sang-Gil;Choi, Ik-Sun
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.38 no.5 s.118
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    • pp.47-53
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    • 2006
  • To meet the ever increasing quality demand of coated papers and duplex boards, the local gloss variation and print unevenness must be avoid. To do this, surface roughening phenomenon which affects local gloss and print unevenness was investigated. In this study, the effect of roughness and densification of sheet obtained at various calendering conditions on surface roughening was examined. To evaluate the calendering effect properly we introduced a new value of roughening index by moisture for evaluation of surface roughening. Caliper and roughness of sheet decreased with increasing of calendering temperature and pressure, and the remarkable reduction of those properties occurred at the temperature around Tg. Roughening index increased when the amount of water increased and calendaring temperature and pressure increased. And as the sheet became denser by calendering, the roughening index increased to some extent. But roughening index by moisture is the lowest for sheet precalendered at higher temperature condition. When the surface of calendered sheet is rougher, there is more roughening of surface. The severe condition of calendering made the roughening index by moisture small.

A Deadlock Free Router Design for Network-on-Chip Architecture (NOC 구조용 교착상태 없는 라우터 설계)

  • Agarwal, Ankur;Mustafa, Mehmet;Shiuku, Ravi;Pandya, A.S.;Lho, Young-Ugh
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.4
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    • pp.696-706
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    • 2007
  • Multiprocessor system on chip (MPSoC) platform has set a new innovative trend for the System on Chip (SoC) design. With the rapidly approaching billion transistors era, some of the main problem in deep sub-micron technologies characterized by gate lengths in the range of 60-90 nm will arise from non scalable wire delays, errors in signal integrity and un-synchronized communication. These problems may be addressed by the use of Network on Chip (NOC) architecture for future SoC. Most future SoCs will use network architecture and a packet based communication protocol for on chip communication. This paper presents an adaptive wormhole routing with proactive turn prohibition to guarantee deadlock free on chip communication for NOC architecture. It shows a simple muting architecture with five full-duplex, flit-wide communication channels. We provide simulation results for message latency and compare results with those of dimension ordered techniques operating at the same link rates.

Design and Implementation of Wireless Asynchronous UWB System for low-rate low power PAN applications (저속도 저전력 PAN 응용을 위한 무선 비동기식 UWB 시스템 설계 및 구현)

  • Choi, Sung-Soo;Koo, In-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.11
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    • pp.2021-2026
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    • 2007
  • In the parer, we design a non-coherent UWB system by adopting the architecture of a simplified asynchronous transmission and the edge-triggered pulse transmission, which makes e system performance independent of the share of the transmitted waveform, robust to multipath channels. The designed non-coherent UWB transceiver architecture has an advantage of the simple realization since any mixer, high-speed correlator, and high-sampling A/D converter are not necessary at the cost of performance degradation of about 3dB. Further, the designed non-coherent UWB transceiver is actually implemented with the wireless CANVAS prototype testbed in short range indoor application environments such as a lecture room. The implemented prototype testbed is proven to offer the data rate of 115kbps on the conditions of Peer-to-Peer(P-to-P) in the indoor channel within the range of about 10m.

The Design of U-Slot Stack Structure Antenna for 800MHz Band Coastal Sea Base Station Applications (800MHz 대역 연안해역기지국용 U-Slot 적층구조 안테나 설계)

  • Kim, Kab-Ki
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.6
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    • pp.984-989
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    • 2008
  • In this paper, we will design a 800MHz broadband antenna after a problem of the narrow bandwidth is improved. This multiple band antenna unifies the CDMA(Code Division Multiple Access), GSM(Global System for Mobile Telecommunication) and TRS(Trunked Radio System) band in the UHF band, and then it is possible at the shore base station or repeater as the commercial use. It used the duplex resonance effect it had the L-shared feeding structure which adds the U-slot. And it improved profit using stack structure. It was measured that the frequency bandwidth of the designed antenna which is planed $792{\sim}1040MHz$ with 248MHz(33%). And the antenna gain is 9.4dBi, 3dB beam width $60^{\circ}$ in radiation pattern.

Comparison of Photophysical and Photochemical Properties of Khellin and 8-Methoxypsoralen

  • Ho Kwon Kang;Eun Ju Shin;Sang Chul Shim
    • Bulletin of the Korean Chemical Society
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    • v.12 no.5
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    • pp.554-559
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    • 1991
  • The photophysical and photochemical properties of khellin were compared with those of 8-methoxypsoralen (8-MOP). Quantum yields of fluorescence and triplet formation decreases as solvent polarity increases, which is opposite to 8-MOP, and photocycloadditivity of khellin to olefins is much lower than that of 8-MOP. Electron ejection from khellin by laser flash was not observed, but observed from 8-MOP. As models of 4',5'-monoadducts of khellin or 8-MOP with thymine base, khellin<>dimethylfumarate 4',5'-monoadduct (KDF) was also compared with 8-MOP<>thymidine 4',5'-monoadduct (F-2) in those properties to give some insight on the second-step biadduct formation resulting in cross-links of DNA duplex. KDF and F-2 were very similar to khellin and 8-MOP in photophysical properties, respectively. However, KDF did not form adducts with various olefins, and thus it is thought that 2,3-double bond of chromone moiety in khellin is hardly reactive in contrast with 3,4-double bond of coumarin moiety in 8-MOP. These results indicate that khellin is fairly photostable compound, a poor type Ⅰ photodynamic sensitizer and producer of ${O_2}^{-}$ which is some cause of phototoxic erythemal reactions and undesirable side effects. Therefore khellin is safer to use than 8-MOP in photochemotherapy of some skin diseases. Although khellin is much less reactive than 8-MOP, khellin must be also a monofunctional drug. Since khellin is, however, as effective as 8-MOP in photochemotherapy of some skin diseases, it is suggested that khellin may be different from 8-MOP in the action mechanism.

Finite element modelling of back-to-back built-up cold-formed stainless-steel lipped channels under axial compression

  • Roy, Krishanu;Lau, Hieng Ho;Lim, James B.P.
    • Steel and Composite Structures
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    • v.33 no.1
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    • pp.37-66
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    • 2019
  • In cold-formed steel structures, such as trusses, wall frames and portal frames, the use of back-to-back built-up cold-formed stainless-steel lipped channels as compression members are becoming increasingly popular. The advantages of using stainless-steel as structural members are corrosion resistance and durability, compared with carbon steel. The AISI/ASCE Standard, SEI/ASCE-8-02 and AS/NZS do not include the design of stainless-steel built-up channels and very few experimental tests or finite element analyses have been reported in the literature for such back-to back cold-formed stainless-steel channels. Current guidance by the American Iron and Steel Institute (AISI) and the Australian and New Zealand (gAS/NZS) standards for built-up carbon steel sections only describe a modified slenderness approach, to consider the spacing of the intermediate fasteners. Thus, this paper presents a numerical investigation on the behavior of back-to-back cold-formed stainless-steel built-up lipped channels. Three different grades of stainless steel i.e., duplex EN1.4462, ferritic EN1.4003 and austenitic EN1.4404 have been considered. Effect of screw spacing on the axial strength of such built-up channels was investigated. As expected, most of the short and intermediate columns failed by either local-global or local-distortional buckling interactions, whereas the long columns, failed by global buckling. All three grades of stainless-steel stub columns failed by local buckling. A comprehensive parametric study was then carried out covering a wide range of slenderness and different cross-sectional geometries to assess the performance of the current design guidelines by AISI and AS/NZS. In total, 647 finite element models were analyzed. From the results of the parametric study, it was found that the AISI & AS/NZS are conservative by around 10 to 20% for cold-formed stainless-steel built-up lipped channels failed through overall buckling, irrespective of the stainless-steel grades. However, the AISI and AS/NZS can be un-conservative by around 6% for all three grades of stainless-steel built-up channels, which failed by local buckling.