• Advances in pediatric surgery
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• 제1권1호
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• pp.27-32
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• 1995

Jejunal and ileal atresias are the most common cause of congenital intestinal obstruction and accounts for about 1/3 of all cases of intestinal obstruction in newborns. Despite the relative frequency of this anomaly, its survival rate was less than 10% up to 1950, more recently the survival rate has risen rapidly to 90% with the introduction of modern surgical techniques and the use of total parenteral nutrition. In 1969 Thomas described a tapering jejunoplasty to manage the discrepancy in the size of the proximal dilated lumen & contracted distal lumen, and to preserve absorptive surface when the dilated jejunum involved a long length, and Grosfeld et al.(1979) facilitated this method by using GIA staplers. Author have also used GIA stapler to resect the antimesenteric portion of the dilated proximal bowel in 8 cases of jejunoileal atresias with good results. The following results were obtained ; 1. There we 3 jejunal atresias & 5 ileal atresias, and male to female sex ratio was 5 : 3. 2. The type of atresia was as follows ; type IIIa was 3 cases, type IIIb was 4 cases, type IIIb+IV was 1 case. 3. In non-complication cases(5 cases), the mean hospital day was 16 days, and oral feeding was feasible from 6.2 days after operation. 4. The complications(anastomotic leakage, pneumonia) were frequently occurred in type IIIb cases and in low birth weight cases(75%). 5. Mortality rate was 25% including DAMA(discharge against medical advice) discharge case.

• Asian Pacific Journal of Cancer Prevention
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• 제13권12호
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• pp.6087-6091
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• 2012

Context: Patients diagnosed with a cancer have a life time risk of developing another de novo malignancy depending on various inherited, environmental and iatrogenic risk factors. Of late the detection of new primary has increased mainly due to refinement in both diagnostic and treatment modalities. Cancer victims are surviving longer and thus are more likely to develop a new metachronous malignancy. Aims: To report our observed trend of increase in prevalence of both synchronous and metachronous second malignant neoplasms among cancer victims and to review the relevant literature. Settings and Design: A hospital based retrospective collection of prospective data of patients diagnosed with second denovo malignancy. Materials and Method: The study was conducted over a 5 year period from July 2008 to June 2012. All patients diagnosed with a histologically proven second malignancy as per Warren Gate's criteria were included. Various details regarding sex, age at presentation, synchronous or metachronous, treatment and outcome were recorded. Conclusions: The occurrence of multiple primary malignancies is not rare. Awareness of the possibility alerts the clinician in evaluation of patients with a known malignancy presenting with unusual sites of metastasis. Individualizing the treatment according to the stages of the primaries will result in durable cancer control particularly in synchronous double malignancy.

• Journal of Positioning, Navigation, and Timing
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• 제9권2호
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• pp.43-50
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• 2020

In this paper a low power Spreading Code Authentication (SCA) sequence with a BPSK(1) modulation at a frequency offset of +7.161 MHz is tested for authentication purposes, the Galileo E1OS is used as base signal. The tested signals comprise a Galileo constellation with 5 satellites including the Galileo OS Navigation Message Authentication (OSNMA) and a low power offset BPSK (OBPSK(7,1)) as SCA component. The signals are generated with the software based MuSNAT-Signal-Generator. The generated signals were transmitted Over-The-Air (OTA) using a Software-Defined-Radio (SDR) as pseudolite. With a real-environment-testbed the performance of the SCA in real channel conditions (fading and multipath) was tested. A new SCA evaluation scheme is proposed and was implemented. Under real channel conditions we derive experimental threshold values for the new SCA evaluation scheme which allow a robust authentication. A Security Code Estimation and Replay (SCER) spoofing attack was mimicked on the real-environment-testbed and analyzed with the SCA evaluation scheme. It was shown that the usage of an OBPSK is feasible as an authentication method and can be used in combination with the OSNMA to improve the authentication robustness against Security SCER attacks.

• Advances in concrete construction
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• 제8권4호
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• pp.311-320
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• 2019

In this study, the effect of cellulose nanocrystals (CNCs) on the fire resistance properties of fiber-reinforced cement composites was investigated. The main variables were CNCs content (0.4, 0.8 and 1.2vol.% compared with cement), steel fiber ratio, and exposure temperature (100, 200, 400, 600 and 800℃). The fire resistance properties, i.e., residual compressive strength, flexural strength, and porosity, were evaluated in relation with the exposure temperature of the specimens. The CNCs suspensions were prepared to composited dispersion method of magnetic stirring and ultra-sonication. CNCs are effective for increasing the compressive strength at high temperatures but CNCs do not seem to have a significant effect on flexural reinforcement. Porosity test result showed CNCs reduce the non-hydration area inside the cement and promote hydration.

• International Journal of Fluid Machinery and Systems
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• 제2권4호
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• pp.303-314
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• 2009

The present paper shows the results of numerical and experimental modal analyses of Francis runners, which were executed in air and in still water. In its first part this paper is focused on the numerical prediction of the model parameters by means of FEM and the validation of the FEM method. Influences of different geometries on modal parameters and frequency reduction ratio (FRR), which is the ratio of the natural frequencies in water and the corresponding natural frequencies in air, are investigated for two different runners, one prototype and one model runner. The results of the analyses indicate very good agreement between experiment and simulation. Particularly the frequency reduction ratios derived from simulation are found to agree very well with the values derived from experiment. In order to identify sensitivity of the structural properties several parameters such as material properties, different model scale and different hub geometries are numerically investigated. In its second part, a harmonic response analysis is shown for a Francis runner by applying the time dependent pressure distribution resulting from an unsteady CFD simulation to the mechanical structure. Thus, the data gained by modern CFD simulation are being fully utilized for the structural design based on life time analysis. With this new approach a more precise prediction of turbine loading and its effect on turbine life cycle is possible allowing better turbine designs to be developed.

• Archives of Plastic Surgery
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• 제42권5호
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• pp.559-566
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• 2015

Background Citation analysis is a recognized scientometric method of classifying cited articles according to the frequency of which they have been referenced. The total number of citations an article receives is considered to reflect it's significance among it's peers. Methods Until now, a bibliometric analysis has never been performed in the specialty of craniofacial anomalies and craniofacial surgery. This citation analysis generates an extensive list of the 50 most influential papers in this developing field. Journals specializing in craniofacial surgery, maxillofacial surgery, plastic surgery, neurosurgery, genetics and pediatrics were searched to demonstrate which articles have cultivated the specialty within the past 55 years. Results The results show an intriguing compilation of papers which outline the fundamental knowledge of craniofacial anomalies and the developments of surgical techniques to manage these patients. Conclusions This citation analysis provides a summation of the current most popular trends in craniofacial literature. These esteemed papers aid to direct our decision making today within this specialty.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 추계학술대회 논문집
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• pp.63-66
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• 2005

Nanoimprint lithography (NIL) process at room temperature has been newly proposed in recent years to overcome the shape accuracy and sticking problem induced in a conventional NIL process. Success of the room temperature NIL relies on the accurate understand of the mechanical behavior of the polymer. Since a conventional NIL process has to heat a polymer above the glass transition temperature to deform the physical shape of the polymer with a mold pattern, viscoelastic property of polymer have major effect on the NIL process. However, rate dependent behavior of polymer is important in the room temperature NIL process because a mold with engraved patterns is rapidly pressed onto a substrate coated with the polymer by the hydraulic equipment. In this paper, finite element analysis of the room temperature NIL process is performed with considering the strain rate dependent behavior of the polymer. The analyses with the variation of imprinting speed and imprinting pattern are carried out in order to investigate the effect of such process parameters on the room temperature NIL process. The analyses results show that the deformed shape and imprint force is quite different with the variation of punch speed because the dynamic behavior of the polymer is considered with the rate dependent plasticity model. The results provide a guideline for the determination of process conditions in the room temperature NIL process.

• 한국수산과학회지
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• 제24권5호
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• pp.356-361
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• 1991

This study was conducted to determine the decomposition rate constants of organic matter and to evaluate the process of regeneration of inorganic nutrients in coastal and open seawater. The mixture solution of glucose and glutamic acid, and night soil were used as the test organic matter. Oxygen uptake of test solution was observed every day for 5 days for evaluation of decomposition rate constants, and nutrient contents were analyzed every day for 40 days. The decomposition rate constants have been determined by Thomas slope method and compared with the values of each waters. The values of rate constants for open seawater and coastal water containing the mixture of glucose and glutamic acid were 0.23/day and 0.21/day, and those containing night soil 0.23/day and 0.20/day, respectively. The difference of decomposition rate constants between test materials was not found and the valus for each seawater was equal to each other. The nitrification process took place after 22 days for open seawater when night soil was added to the waters.

• 한국디지털건축인테리어학회논문집
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• 제12권4호
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• pp.97-105
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• 2012

This study aims to evaluate Rietveld's creative design style and concepts. To this end, I looked into the evaluation of major researchers on Rietveld, classified all his works into four groups according to the design types and analyzed them. As follows: based on the results of the analysis of works I concluded. First, Rietveld created the concept of the spatial extension to the ingenious joint which had the structural node formed of three listels with quadrangular section. It is the design innovation that led to liberate the closed construction. Second, Rietveld had opened up the possibility to neutralize the gravitational three-dimensional works. He subtracted the weight in the direction of gravity from the three-dimensional structure of the works and painted the three primary colors on them partially to get rid of the original material color. Therefore they looked like the forms liberated from gravity. Third, Rietveld ripped off the surfaces of cube through several formative experiments and decomposed the volume into the tesseract. Through this method of realizing the new plastic concepts, he completed the architectural models of weightlessness. Fourth, Rietveld opened the possibility of the realization of the three-dimensional works integrated all space and time in the one-pieced works and the folded works. Fifth, Rietveld steadily experimented and realized the internal and external integration of time and space in his later works.

• Journal of Power Electronics
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• 제5권3호
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• pp.198-205
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• 2005

The mechanical system of a drive can often be modeled as a two- or three-mass-system. The load is coupled to the driving motor by a shaft able to perform torsion oscillations. For the automatic tuning of the control, it is necessary to know the mathematical description of the system and the corresponding parameters. As the manpower and setup-time necessary during the commissioning of electrical drives are major cost factors, the development of self-operating identification strategies is a task worth pursuing. This paper presents an identification method which can be utilized for the assisted commissioning of electrical drives. The shaft assembly can be approximated as a two-mass non-rigid mechanical system with four parameters that have to be identified. The mathematical background for an identification procedure is developed and some important implementation issues are addressed. In order to avoid the excitation of the system with its natural resonance frequency, the frequency response can be obtained by exciting the system with a Pseudo Random Binary Signal (PRBS) and using the cross correlation function (CCF) and the auto correlation function (ACF). The reference torque is used as stimulation and the response is the mechanical speed. To determine the parameters, especially in advanced control schemes, a numerical algorithm with excellent convergence characteristics has also been used that can be implemented together with the proposed measurement procedure in order to assist the drive commissioning or to achieve an automatic setting of the control parameters. Simulations and experiments validate the efficiency and reliability of the identification procedure.