• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.7
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• pp.3431-3445
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• 2017

Due to the advantages of low transmit power consumption, high spectral efficiency and extended system coverage, Device-to-Device (D2D) communication has drawn explosive attention in wireless communication field. Considering that intra-cell interference caused between cellular signals and D2D signals, in this paper, a network coding-based D2D relay cooperative transmission algorithm is proposed. Under D2D single-hop relay transmission mode, cellular interfering signals can be regarded as useful signals to code with D2D signals at D2D relay node. Using cellular interfering signals and network coded signals, D2D receiver restores the D2D signals to achieve the effect of interference suppression. Theoretical analysis shows that, compared with Amplify-and-forward (AF) mode and Decode-and-forward (DF) mode, the proposed algorithm can dramatically increase the link achievable rate. Furthermore, simulation experiment verifies that by employing the proposed algorithm, the interference signals in D2D communication can be eliminated effectively, and meanwhile the symbol error rate (SER) performance can be improved.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.5989-5993
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• 2013

Background: Radiation therapy is the mainstay of treatment for nasopharyngeal carcinoma. Importance of tumor coverage and challenges posed by its unique and critical location are well evident. Therefore we aimed to evaluate our radiation treatment plan through dose volume histograms (DVHs) to find planning target volume (PTV) dose coverage and factors affecting it. Materials and Methods: This retrospective study covered 45 histologically proven nasopharyngeal cancer patients who were treated with definitive 3D-CRT and chemotherapy between Feb 2006 to March 2013 at the Department of Oncology, Section Radiation Oncology, Aga Khan University Hospital, Karachi, Pakistan. DVH was evaluated to find numbers of shrinking field (phases), PTV volume in different phases and its coverage by the 95% isodose lines, along with influencing factors. Results: There were 36 males (80%) and 9 females (20%) in the age range of 12-84 years. Stage IVA (46.7%) was the most common stage followed by stage III (31.1). Eighty six point six-percent received induction, 95.5% received concurrent and 22.2% received adjuvant chemotherapy. The prescribed median radiation dose was 70Gy to primary, 60Gy to clinically positive neck nodes and 50Gy to clinically negative neck regions. Mean dose to spinal cord was 44.2Gy and to optic chiasma was 52Gy. Thirty seven point eight-percent patients completed their treatment in three phases while 62.2% required four to five phases. Mean volume for PTV3 was $247.8cm^3$ (50-644.3), PTV4 $173.8cm^3$ (26.5-345.1) and PTV5 $119.6cm^3$ (18.9-246.1) and PTV volume coverage by 95% isodose lines were 74.4%, 85.7% and 100% respectively. Advanced T stage, intracranial extension and tumor volume > $200cm^3$ were found to be important factors associated with decreased PTV coverage by 95% isodose line. Conclusions: 3D CRT results in adequate PTV dose coverage by 95% isodose line. However advanced T stage, intracranial extension and large target volume require more advanced techniques like IMRT for appropriate PTV coverage.

• International Journal of Computer Science & Network Security
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• v.21 no.1
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• pp.152-161
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• 2021

The paper focuses on Device-to-device (D2D) Architectures evaluation frameworks. D2D communication and discovery can improve spectrum usage efficiency and optimize the tradeoffs between throughput and energy consumption. The target operation modes involve both indirect communication between two nodes via a base station or the direct communication among proximal nodes, enabling use cases that can support communications out of cellular coverage, as well as low end-end delay requirements. The paper will present the architectural evolution of D2D networks within 3GPP standardization and will highlight key network functionalities and signaling protocols. It will also identify key analytical and simulation models that can be used to assess the performance and energy efficiency of resource allocation strategies, and it will present a suitable cross-layer integrated framework.

• The KIPS Transactions:PartA
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• v.9A no.4
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• pp.519-524
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• 2002

In this paper we study the qualify of sequential coverage analysis under a scenario of distributed stochastic simulation known as MRIP(Multiple Replications In Parallel) in terms of the confidence intervals of coverage and the speedup. The estimator based in the F-distribution was applied to the sequential coverage analysis of steady-state means. in simulations of the $M/M/1/{\infty},\;M/D/I/{\infty}\;and\;M/H_{2}/1/{\infty}$ queueing systems on a single processor and multiple processors. By using multiple processors under the MRIP scenario, the time for collecting many replications needed in sequential coverage analysis is reduced. One can also easily collect more replications by executing it in distributed computers or clusters linked by a local area network.

• Journal of Periodontal and Implant Science
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• v.51 no.2
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• pp.77-87
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• 2021

Purpose: The aim of this study was to compare the efficacy of the tunnel technique for root coverage using a new xenogeneic acellular dermal matrix vs. connective tissue grafting (CTG) for the treatment of multiple maxillary adjacent recessions (recession type 1) at 12 months postoperatively. Methods: This study enrolled 12 patients with at least 3 contiguous, bilateral, symmetrical maxillary gingival recessions (i.e., at least 6 recessions per patient). In total, 74 recessions were treated using the modified coronally advanced tunnel (MCAT) technique combined with a novel porcine-derived acellular dermal matrix (PADM) at 37 test sites or CTG at 37 control sites. The following clinical parameters were measured: recession height, clinical attachment level, width of keratinized tissue, probing depth, recession width, gingival thickness, mean root coverage (MRC), and complete root coverage (CRC). Comparisons between test and control groups were made for pain visual analog scale scores at 14 days. Results: At 12 months, the MCAT with PADM (test) yielded a statistically significant improvement in all clinical parameters studied. MRC was significantly higher on the control sides (80.6%±23.7%) than on the test sides (68.8%±23.4%). Similarly, CRC was 48.7%±6.8% on the control sides (CTG), in contrast to 24.3%±8.2% on the test sides (PADM). Statistically significant differences were observed in favor of the control sides for all clinical parameters studied. Nevertheless, the MCAT in adjunction with PADM was clearly superior at reducing mean and maximum patient-reported postoperative pain intensity and pain duration in the first week after surgery. Conclusions: The use of PADM to treat multiple recessions improved clinical parameters at 12 months, but these outcomes were nevertheless poorer than those observed for CTG. However, PADM reduced morbidity, particularly the pain experienced by patients.

• STI Policy Review
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• v.2 no.1
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• pp.35-53
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• 2011

This paper originates from the questions concerning why Korea has had difficulties in boosting R&D service industries regardless of government efforts over a decade. We first review the intrinsic nature of the R&D services and set up four criteria such as establishment type, diversification of business models, coverage of client firms, and role of R&D service firms as innovation drivers and IP strategies, that will be used in interviewing and analyzing R&D service firms. Second, we carry out in-depth interviews of eighteen R&D service firms to understand business behaviors and relevant characteristics. Finally, we identify five groups of R&D service firms and conclude that differentiated polices have to be implemented according to the groups for promoting the industry effectively.

• The Journal of the Korean dental association
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• v.58 no.1
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• pp.8-18
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• 2019

This case report presents results for gingival recession coverage following gingival grafting and for gingival biotype enhancements by visualizing soft tissue volume changes using intraoral three-dimensional scanning. A 28 year old female patient with multiple gingival recessions and a 19 year old female patient with a single gingival recession on mandibular anterior area were treated. Root coverage was performed in both cases using autogenous subepithelial connective tissue harvested from palate. Intraoral 3D scan data were obatained presurgery and at 3 months, 1 year, and 2 years postsurgery. The recession areas were recovered successfully by subepithelial connective tissue graft combined with pedicle flap repositioning, and the patients showed neither further recurrence nor post-operative complication. Soft tissue biotype changes were identified by superimposing and analyzing scan data, revealing that gingival biotype was enhanced in both cases. These cases suggest that SCTG could be advantageous in terms of the gingival biotype enhancement, as well as gingival recession coverage, and intraoral 3D scanning might be suitable for assessing post-surgical gingival biotype change.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.265-265
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• 2012

The adsorption of molecular $NH_3$ on rutile $TiO_2(110)-1{\times}1$ surfaces was investigated using a temperature-programmed desorption (TPD) technique combined with a molecular beam apparatus. A quantitative investigation into the TPD spectra of $NH_3$ was made for $NH_3$ adsorbed on two kinds of rutile $TiO_2(110)-1{\times}1$ surfaces with the oxygen vacancy ($V_O$) concentration of ~0% (p-$TiO_2(110)$) and ~5% (r-$TiO_2(110)$), respectively. On both surfaces, non-dissociative adsorption of $NH_3$ was inferred from a quantitative analysis on the amount of adsorbed $NH_3$ and those desorbed. With increasing coverage, the monolayer desorption feature shifted from 400 K toward lower temperatures until it saturates at 160 K, suggesting a repulsive nature in the interaction between $NH_3$ molecules. At the very low coverage regime, the desorption features were found to extend up to 430 K and 400 K on p-$TiO_2(110)$ and p-TiO(110), respectively. As a result, the saturation coverage of monolayer of $NH_3$ was higher on the p-$TiO_2(110)$ surface than on the p-TiO(110) by about 10%. The desorption energy ($E_d$) of $NH_3$ obtained by inversion of the Polanyi-Wigner equation indicated that the difference between the $E_d$'s of $NH_3$ (that is, $E_d(on\;p-TiO_2(110)$) - $E_d$(on p-TiO(110)) was 14 kJ/mol at ${\theta}(NH_3)=0$ and decreased to 0 as the coverage approached to a monolayer. The observed adsorption behavior of $NH_3$ was interpreted using an interaction model between $NH_3$ and surface defects on $TiO_2$ such as VO's and $Ti^{3+}$ interstitials.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.2D
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• pp.155-162
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• 2008

This study shows how to estimate the design hour factor when the counting stations don't have all of the hourly volumes such as in a coverage survey. A coverage survey records traffic volume from 1 to 5 times in a year so it lacks the detailed information to calculate the design hour factor. This study used the traffic volumes of permanent surveys to estimate the design hour factor in coverage surveys using correlation and regression analysis. A total 7 independent variables are used : the coefficient of variance of hourly volume, standard deviation of hourly volume, peak hour volume, AADT, heavy traffic volume proprotion, day time traffic volume proportion and D factor. All of variables are plotted on a curve, so it must use non-linear regression to analyze the data. As a result the coefficient of determination and MAE are good at logarith model using AADT.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.12
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• pp.4946-4960
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• 2020

In a device-to-device (D2D) underlaid cellular network, there exist two types of co-channel interference. One type is inter-layer interference caused by spectrum reuse between D2D transmitters and cellular users (CUEs). Another type is intra-layer interference caused by spectrum sharing among D2D pairs. To mitigate the inter-layer interference, we first derive the interference limited area (ILA) to protect the coverage probability of cellular users by modeling D2D users' location as a Poisson point process, where a D2D transmitter is allowed to reuse the spectrum of the CUE only if the D2D transmitter is outside the ILA of the CUE. To coordinate the intra-layer interference, the spectrum sharing criterion of D2D pairs is derived based on the (signal-to-interference ratio) SIR requirement of D2D communication. Based on this criterion, D2D pairs are allowed to share the spectrum when one D2D pair is far from another sufficiently. Furthermore, to maximize the energy efficiency of the system, a resource allocation scheme is proposed according to weighted graph coloring theory and the proposed ILA restriction. Simulation results show that our proposed scheme provides significant performance gains over the conventional scheme and the random allocation scheme.