• Journal of Power Electronics
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• 제17권1호
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• pp.262-271
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• 2017

This paper studies the performances of five typical Phase-locked Loops (PLLs) for distorted and unbalanced grid, which are the Decoupled Double Synchronous Reference Frame PLL (DDSRF-PLL), Double Second-Order Generalized Integrator PLL (DSOGI-PLL), Double Second-Order Generalized Integrator Frequency-Lock Loop (DSOGI-FLL), Double Inverse Park Transformation PLL (DIPT-PLL) and Complex Coefficient Filter based PLL (CCF-PLL). Firstly, the principles of each method are meticulously analyzed and their unified small-signal models are proposed to reveal their interior relations and design control parameters. Then the performances are compared by simulations and experiments to investigate their dynamic and steady-state performances under the conditions of a grid voltage with a negative sequence component, a voltage drop and a frequency step. Finally, the merits and drawbacks of each PLL are given. The compared results provide a guide for the application of current control, low voltage ride through (LVRT), and unintentional islanding detection.

• Advances in pediatric surgery
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• 제14권1호
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• pp.88-93
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• 2008

Esophageal atresia with double tracheoesophageal fistula is a very rare anomaly and is difficulty to diagnose preoperatively. We treated a full term baby with esophageal atresia with double tracheoesophageal fistula. At the first operation, only the distal tracheoesophageal fistula was identified and ligated. When the upper esophageal pouch was opened, intermittent air leakages in sequence with positive bagging were noticed. However, intraoperative bronchoscopy did not identify a fistula in the proximal pouch, and the operation was completed with end to end anastomosis of the esophagus. On the $7^{th}$ postoperative day, esophagography showed another tracheoesophageal fistula proximal to the esophageal anastomosis. A wire was placed in the fistula preoperatively under bronchoscopy. At the 2nd operation through the same thoracotomy incision the proximal fistula was identified and ligated. On the $12^{th}$ postoperative day, esophagography showed neither stricture nor leakage.

• Composites Research
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• 제31권6호
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• pp.340-346
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• 2018

본 연구에서는 20mm 범용탄약적재장비의 운행 시 탄약의 운동에 관여하는 이중리드나선의 설계를 위해 이중리드나선에 발생하는 응력과 변형에 대하여 ABAQUS 프로그램을 이용해서 해석한다. 해석을 위해 복합재를 적용한 나선형 물체의 회전 시 발생하는 응력 해석의 타당성을 확인한다. 이중리드나선의 재료를 일반 금속과 복합재로 적용하여 해석하고 모델을 복합재료로 대체 하였을 때 이점을 제시한다. 또한 복합재료의 적층각과 적층순서, 회전속도의 변경 시에 발생하는 응력과 변형을 예측하고, Tsai-Wu failure 이론에 해석결과를 적용하여 파손을 확인하며. 탄약적재시 스텝의 개발을 위한 복합재 이중나선구조의 설계결과를 제시한다.

• 한국약용작물학회지
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• 제24권1호
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• pp.55-61
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• 2016

Background : Plant breeding requires the collection of genetically diverse genetic resources. Studies on the characteristics of Platycodon grandiflorum resources have not been carried out so far. The present study was carried out to discriminate P. grandiflorum based on morphological characteristics and genetic diversity using simple sequence repeat (SSR) markers. Methods and Results :We collected 11 P. grandiflorum cultivars: Maries II, Hakone double white, Hakone double blue, Fuji white, Fuji pink, Fuji blue, Astra white, Astra pink, Astra blue, Astra semi-double blue and Jangbaek. Analyses of the morphological characteristics of the collection were conducted for aerial parts (flower, stem and leaf) and underground parts (root). Next, the genetic diversity of all P. grandiflorum resources was analyzed using SSR markers employing the DNA fragment analysis method. We determined that the 11 P. grandiflorum cultivars analyzed could be classified by plant length, leaf number and root characteristic. Based on the genetic diversity analysis, these cultivars were classified into four distinct groups. Conclusions : These findings could be used for further research on cultivar development using molecular breeding techniques and for conservation of the genetic diversity of P. grandiflorum. Moreover, the markers could be used for genetic mapping of the plant and marker-assisted selection for crop breeding.

• Journal of Yeungnam Medical Science
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• 제34권2호
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• pp.270-274
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• 2017

A nodular density was detected on a chest radiograph taken from a 57-year-old Korean woman who was visiting a hospital for a routine check. Chest computed tomography revealed a 4.8 cm lobulated mass in the right lung and another focal nodular lesion in the left lung; biopsies of both lungs revealed adenocarcinoma. We conducted DNA sequencing and peptide nucleic acid clamping to investigate the potential double primary lung cancer. The results verified that the mass in the right lung had a mutation in the epidermal growth factor receptor, whereas the nodule in the left lung had a wild-type sequence, showing that these two were genetically different cancers from one another. Thus, we demonstrate that genetic testing is useful in determining double primary lung cancer, and we herein report on this case.

• 한국정보과학회논문지:소프트웨어및응용
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• 제28권12호
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• pp.947-954
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• 2001

본 논문에서는 인식된 얼굴의 포즈 상태 열에 오토마타 기법을 적용하여 다양한 헤드 제스처 를 인식하는 방법을 제안한다. 얼굴 영역의 추출에는 Yl7외 I성분인 최적의 얼굴색 정보와 적응적인 차영상 정보를 이용하며. 눈 영역 추출에는 소벨 연산자와 투영 기법. 그리고 눈의 기하학적 위치 정보를 이용 한다 얼굴의 상태 인식에는 계층적인 특징분석 방법을 사용하며, 인식된 얼굴 상태 열에 오토마타 기법을 적용하여 13가지 제스처; 준비, 상측, 하측, 좌측, 우측, 전진, 후퇴, 좌 윙크, 우 윙크, 좌 더블 윙크 우 더블 윙크, 긍정, 부정제스처를 인식한다. 총 8명으로부터 1,488 프레임의 영상을 취득하여 실험한 결과, 99.3%의 얼굴 영역 추출률 95.3%, 의 눈 영역 추출률, 94.1% 의 얼굴 상태 인식률. 그리고 93.3%의 헤드제 스처 인식률을 얻었다

• Parasites, Hosts and Diseases
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• 제45권2호
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• pp.87-94
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• 2007

In this study, we describe Korean isolates of Trichomonas vaginalis infected with double-stranded (ds) RNA virus (TVV). One T. vaginalis isolate infected with TVV IH-2 evidenced weak pathogenicity in the mouse assay coupled with the persistent presence of a dsRNA, thereby indicating a hypovirulence effect of dsRNA in T. vaginalis. Cloning and sequence analysis results revealed that the genomic dsRNA of TVV IH-2 was 4,647 bp in length and evidenced a sequence identity of 80% with the previously-described TVV 1-1 and 1-5, but only a 42% identity with TVV 2-1 and 3 isolates. It harbored 2 overlapping open reading frames of the putative capsid protein and dsRNA-dependent RNA polymerase (RdRp). As previously observed in the TVV isolates 1-1 and 1-5, a conserved ribosomal slip-page heptamer (CCUUUUU) and its surrounding sequence context within the consensus 14-nt overlap implied the gene expression of a capsid protein-RdRp fusion protein, occurring as the result of a potential ribosomal frameshift event. The phylogenetic analysis of RdRp showed that the Korean TVV If-2 isolate formed a compact group with TVV 1-1 and 1-5 isolates, which was divergent from TVV 2-1, 3 and other viral isolates classified as members of the Giardiavirus genus.

• 한국환경농학회지
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• 제29권1호
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• pp.77-85
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• 2010

Reactive oxygen species (ROS) are very harmful to living organisms due to the potential oxidation of membrane lipids, DNA, proteins, and carbohydrates. transformed E.coli strain QC 871, superoxide dismutase (SOD) double-mutant, with three sequence variant MnSOD1, MnSOD2, and MnSOD3 manganese superoxide dismutase (MnSOD) gene isolated from wheat. Although all QC 871 transformants grown at $37^{\circ}C$ expressed mRNA of MnSOD variants, only MnSOD2 transformant had functional SOD activity. MnSOD3 expressed active protein when grown at $22^{\circ}C$, however, MnSOD1 did not express functional protein at any growing and induction conditions. The sequence comparison of the wheat MnSOD variants revealed that the only amino acid difference between the sequence MnSOD2 and sequences MnSOD1 and 3 is phenylalanine/serine at position 58 amino acid. We made MnSOD2S58F gene, which was made by altering the phenylalaine to serine at position 58 in MnSOD2. The expressed MnSOD2S58F protein had functional SOD activity, even at higher levels than the original MnSOD2 at all observed temperatures. These data suggest that amino acid variation can result in highly active forms of MnSOD and the MnSOD2S58F gene can be an ideal target used for transforming crops to increase tolerance to environmental stresses.

• Journal of Electrical Engineering and Technology
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• 제8권3호
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• pp.499-506
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• 2013

The accurate estimation of a fault location is desired in distance protection schemes for transmission lines in order to selectively deactivate a faulted line. However, a typical method to estimate a fault location by calculating impedances with voltages and currents at relaying points may have errors due to various factors such as the mutual impedances of lines, fault impedances, or effects of parallel circuits. The proposed algorithm in this paper begins by extracting the fundamental phasor of the positive sequence currents from the three phase currents. The second-order difference of the phasor is then calculated based on the fundamental phasor of positive sequence currents. The traveling times of the waves generated by a fault are derived from the second-order difference of the phasor. Finally, the distance from the relaying point to the fault is estimated using the traveling times. To analyze the performance of the algorithm, a power system with EHV(Extra High Voltage) untransposed double-circuit transmission lines is modeled and simulated under various fault conditions, such as several fault types, fault locations, and fault inception angles. The results of the simulations show that the proposed algorithm has the capability to estimate the fault locations with high speed and accuracy.

• Structural Engineering and Mechanics
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• 제55권3호
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• pp.555-581
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• 2015

Triangular pyramid and Quadrangular pyramid elements for partial double-layer spherical reticulated shells of pyramidal system are investigated in the present study. Macro programs for six typical partial double-layer spherical reticulated shells of pyramidal system are compiled by using the ANSYS Parametric Design Language (APDL). Internal force analysis of six spherical reticulated shells is carried out. Distribution regularity of the stress and displacement are studied. A shape optimization program is proposed by adopting the sequence two-stage algorithm (RDQA) in FORTRAN environment based on the characteristics of partial double-layer spherical reticulated shells of pyramidal system and the ideas of discrete variable optimization design. Shape optimization is achieved by considering the objective function of the minimum total steel consumption, global and locality constraints. The shape optimization of six spherical reticulated shells is calculated with the span of 30m~120m and rise to span ratio of 1/7~1/3. The variations of the total steel consumption along with the span and rise to span ratio are discussed with contrast to the results of shape optimization. The optimal combination of main design parameters for six spherical reticulated shells is investigated, i.e., the number of the optimal grids. The results show that: (1) The Kiewitt and Geodesic partial double-layer spherical reticulated shells of triangular pyramidal system should be preferentially adopted in large and medium-span structures. The range of rise to span ratio is from 1/6 to 1/5. (2) The Ribbed and Schwedler partial double-layer spherical reticulated shells of quadrangular pyramidal system should be preferentially adopted in small-span structures. The rise to span ratio should be 1/4. (3) Grids of the six spherical reticulated shells can be optimized after shape optimization and the total steel consumption is optimized to be the least.