• Journal of electromagnetic engineering and science
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• v.14 no.2
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• pp.47-53
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• 2014

This paper presents a high gain and high harmonic rejection low-noise amplifier (LNA) for software-defined radio receiver. This LNA exploits the high quality factor (Q) series resonance technique. High Q series resonance can amplify the in-band signal voltage and attenuate the out-band signals. This is achieved by a source impedance transformation. This technique does not consume power and can easily support multiband operation. The chip is fabricated in a $0.13-{\mu}m$ CMOS. It supports four bands (640, 710, 830, and 1,070MHz). The measured forward gain ($S_{21}$) is between 12.1 and 17.4 dB and the noise figure is between 2.7 and 3.3 dB. The IIP3 measures between -5.7 and -10.8 dBm, and the third harmonic rejection ratios are more than 30 dB. The LNA consumes 9.6 mW from a 1.2-V supply.

• Archives of Plastic Surgery
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• v.50 no.2
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• pp.194-199
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• 2023

Moderate soft-tissue defects need stable coverage, ideally with tissue of similar characteristics and low donor site morbidity. We propose a simple technique for the coverage of moderate skin defects in the limbs. It allows intraoperative transformation of a propeller perforator flap (PPF) into a keystone design perforator flap (KDPF) in cases of unsatisfying perforator vessel or in cases of unpredictable intraoperative events. Between March 2013 and July 2019, nine patients with moderate soft-tissue defects (mean defect size 4.5 × 7.6 cm) in the limbs (two on the upper limbs and seven on the lower limbs) were covered using this technique. We performed four PPFs and five KDPFs. The mean follow-up was 5 months. There was one complication, partial distal tip necrosis in a PPF located in the leg, which healed by secondary intention within 3 weeks. The donor site was closed directly in all cases. No functional impairments were noted regardless of the perforator flap utilized. This technique enables us to employ flexible surgical strategies and allows us to make adjustments based on the patient's vascular anatomy.

• Journal of the Korea Society of Computer and Information
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• v.17 no.6
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• pp.131-144
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• 2012

MDD is suitable to satisfy constraints of development of mobile applications. So, there are various studies about applying MDD to the developments of mobile application but systematic development methods about UML profile for PIM/PSM of mobile applications and model transformation techniques are needed. This paper suggests that a development technique about UML profile for PIM/PSM of mobile applications and a model transformation techniques with the profiles. We classify stereotypes by the characteristics of mobile application to compose profiles and suggest development guidelines of profiles for PIM/PSM. On the suggested model transformation process, the PIM with the profiles is transformed to the intial PSM with the mapping rules and the PSM is transformed to the refined PSM with templates which reflected detailed information of a mobile platform. We developed a location based service mobile application with the suggested techniques on the Android platform and compared with other techniques to validate usefulness of the suggested techniques.

• Journal of the Korea Society of Computer and Information
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• v.16 no.3
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• pp.53-63
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• 2011

Many techniques have been proposed to store and query XML data efficiently. One way achieving this goal is using relational database by transforming XML data into relational format. It is important to transform schema to preserve the content, the structure and the constraints of the semantics information of the XML document. Especially, key constraints are an important part of database theory. Therefore, the proposal technique has considered the semantics of XML as expressed by primary keys and foreign keys. And, the proposal technique can preserve not only XML data constraints but also the content and the structure and the semantics of XML data thru transformation process. Transforming information is the content and the structure of the document(the parent-child relationship), the functional dependencies, semantics of the document as captured by XML key and keyref constraints. Because of XML schema transformation ensures that preserving semantic constraints, the advantages of these transformation techniques do not need to use the stored procedure or trigger which these data ensures data integrity in the relational database. In this paper, there is not chosen the ID/IDREF key which supported in DTD, the inheritance relationship, the implicit referential integrity.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.1
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• pp.42-48
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• 2006

In this study, a repetitive response surface enhancement technique (RRSET) is proposed as a new system approximation method for the efficient multidisciplinary design and optimization (MDO). In order to represent the highly nonlinear behavior of the response with second order polynomials, RRSET introduces a design space transformation using stretching functions and repetitive response surface improvement. The tentative optimal point is repetitively included to the set of experimental points to better approximate the response surface of the system especially near the optimal point, hence a response surface with significantly improved accuracy can be generated with very small experimental points and system iterations. As a system optimizer, the simulated annealing, which generates a global design solution is utilized. The proposed technique is applied to several numerical examples, and demonstrates the validity and efficiency of the method. With its improved approximation accuracy, the RRSET can contribute to resolve large and complex system design problems under MDO environment.

• Journal of Korean Society of Steel Construction
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• v.18 no.1
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• pp.1-10
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• 2006

paper presents the results of the use of the differential transformation technique in analyzing the free vibration of circular plates.calculations were carried out and were compared with previously published results. The results that were obtained when this method was used coincide with the results of The present analysis shows the usefulness and validity of differential transformation in solving a solid-circular and annular-plate problem in terms of free-vibration responses.

• Journal of the Korean Society for Heat Treatment
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• v.7 no.4
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• pp.233-243
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• 1994

Constitutive relation of thermoelasto-plastic material undergoing phase transformation during quenching process were developed on the basic of continuum thermodynamics. The metallic structure, temperature and residual stresses distributions were numerically calculated by the finite element technique. The metallic structure were defined by transformation from austenite to pearlite and characterized as a fuction of thermal history and mixture rule of phase. On the distribution of thermal stress along the radial direction, axial and tangential stresses are compressive in the surface, and tential in the inner part. Radial stress is tensile in the whole body. The reversion of residual stress takes plase at 11.5~15.5mm from the center.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.11a
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• pp.809-814
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• 2006

In this paper, the modified direct method employing beam transformation technique is proposed in order to efficiently calculate hydroelastic responses of floating structure. Since the proposed method expresses the displacements of three-dimensional structure with those of transformed beam which leads to small number of equations of motion, the method is numerically efficient compared to the conventional direct method. To verify the efficiency of the proposed method a 500 m-long floating structure under wave loads is considered in numerical example. Displacements, bending moments, torsion moments and shear forces are calculated and computing tine is examined. The results are also compared with those of the conventional direct method.

• YAKHAK HOEJI
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• v.40 no.2
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• pp.212-217
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• 1996

Streptomyces cattleya is a producer of carbapenem antibiotics, thienamycin and N-acetylthienamycin, which have potent and broad-spectrum antibacterial activities. We stud ied on strain improvement for antibiotic productivity of S. cattleya by transformation technique which employed S.cattleya protoplasts and chromosomal DNAs of glutamic acid producers: Corynebacterium glutamicum and Arthrobacter simplex. 150 Transformant strains were cultured and bioassayed using Bacillus subtilis and Staphylococcus aureus as test organisms. 8.7% of transformants tested showed 1.4~2.6 fold higher productivities than wild type which produced $1.61{\pm}0.67{\mu}g/ml$. The best transformant produced $8.36{\pm}2.84{\mu}g/ml$ carbapenems.

• ETRI Journal
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• v.27 no.2
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• pp.223-226
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• 2005

This paper presents the application of a turbo coding technique combined with a bandwidth efficient method known as trellis-coded modulation. A transformation applied to the incoming I-channel and Q-channel symbols allows the use of an off-the-shelf binary/quadrature phase shift keying (B/QPSK) turbo decoder without any modifications. A conventional turbo decoder then operates on transformed symbols to estimate the coded bits. The uncoded bits are decoded based on the estimated coded bits and locations of the received symbols.