• Journal of Welding and Joining
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• v.34 no.5
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• pp.33-40
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• 2016

The microstructures and the creep rupture properties of dissimilar welds between the Ni-based superalloy Inconel 740H and the non-stabilized austenitic stainless steel TP316H have been characterized. The welds were produced by shielded metal arc (SMA) welding process with the AWS A5.11 Class ENiCrFe-3 filler metal, commonly known as Inconel 182 superalloy. Postweld heat treatment at $760^{\circ}C$ for 4 hours was conducted to form ${\gamma}^{\prime}$ strengthener in Inconel 740H. The austenitic weld metal produced by Inconel 182 had a dendritic microstructure, and grew epitaxially from the both sides of Inconel 740H and TP316H base metals. Since both Inconel 740H and TP316H did not undergo any solid-state transformation during welding process, there were no heat-affected-zone (HAZ) sub-regions and the coarsoned grains near the weld interface were limited to a narrow region. The hardness of Inconel 182 weld metal was ~220 Hv. The gradual hardness decrease was detected at HAZ of TP316H, and the TP316H base metal displayed the lowest hardness value (~180 Hv) whilst the Inconel 740H showed the highest hardness value (~400 Hv). Fracture after creep occurred at the center of weld metal, regardless of creep condition. It was found that during creep the cracks initiated and propagated along interdendritic regions and grain boundaries at which Laves particles enriched in Nb, Si and Cr were present. The appropriate design of weld metal was discussed to suppress the creep-induced cracking of the present dissimilar weld.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.2
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• pp.83-94
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• 2020

Busan Metropolitan City, a research site of this study, was promoted to a metropolitan city in 1995 with the implementation of the local autonomy system, and the overall change was made as it absorbed the surrounding areas to address the shortage of population and space. Twenty-five years after the introduction of the local autonomy system, it is necessary to diagnose whether balanced development of the entire city is being made in accordance with the reorganization of the metropolitan city in terms of spatial structure. In this study, changes in spatial structure and regional characteristics were analyzed by applying population potential, which means potential for future spatial interaction, in time and space. According to the analysis, the development was taking place around the center area and the sub-center established by the urban master plan, but Gangseo-gu and Gijang-gun, which were incorporated in the past, remained stagnant. In addition, it was shown that the spatial expansion of the city was suppressed by the green belt surrounding the city. However, in other regions where the green belt is located, the city has been expanded, which is different from Gijang-gun or Gangseo-gu, which was incorporated into the metropolitan city. Therefore, the cause of the decline in incorporated areas should not be limited to the institutional dimension of land use regulation. Growth management and balanced development plans will be necessary for the development of declining old downtowns and underdeveloped incorporated areas.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.1
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• pp.79-84
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• 2004

Pilomatricoma is a benign soft tissue tumor of hair follicle origin. They occur most commonly in the head and neck region and are usually found in girls during the first two decades of life. Although malignant transformation has been described, it is exceedingly rare. The clinical presentation is typically that of an asymptomatic, superfical, solitary, firm mass that is often accompanied by a reddish-blue discoloration of the overlying skin. Histopathologically pilomatricoma are seen as epithelial islands embedded in a cellular stroma. The epithelial component consist of two main cell types : basaloid cells and ghost cells. Intracellular and stromal calcification is reported in many cases. Diagnosis is usually suspected based on palpation of a superficial, rock-hard mass and confirmed by histopathologic examination. Surgical excision is both curative and the treatment of choice. Recurrence is rare. In this case, the radiographs showed a dense calcification, measuring about 1cm diameter. So simple excision was peformed intraorally, and resultantly the lesion was proved to be a pilomatricoma by histological examination.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.3
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• pp.262-269
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• 2011

Ameloblastic fibroma is rare true benign mixed odontogenic tumor. Most of these tumors occur in the posterior region of the mandible under 20 years of age. It develops generally associated with unerupted tooth and grows slowly on the surface of alveolar bone, therefore interferes normal tooth eruption. These lesions rarely showing a little bony expansion, are usually asymptomatic and are discovered incidentally on routine dental exam. It is similar to amleoblastic fibroodontoma and ameloblastic fibrodentinoma clinically and roentgenographically but represents no dental hard tissue formation histologically. Enucleation and curettage of surrounding bone are generally recommended options for treatment. Even though there are some reports of recurrence and malignant transformation and more aggressive treatment options like block resection are suggested sometimes, but in most cases, recurrence is unusual because it is well encapsulated and easily separated from adjucent bony socket. In these cases, we did conservative treatment such as enucleation and curettage to the patients who were visited for ameloblastic fibroma associated with delayed eruption of lower first molar. After regular check-ups, we found relatively natural eruption process of combined teeth.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.4_1
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• pp.129-136
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• 1992

A precedure for recovering surface displacement from a time series of pressure measured by a pressure gage in a shallow water (that is, FFTM, LCM. IWM) is investigated with respect to a proper cut-off-frequency of a frequency response function for the accurate recovery of wave height and period. The authors examined the applicability of above mentioned three transformation procedures through field observations and laboratory experiments and the following results are obtained. i) The cut-off-frequency of the frequency response function used in FFTM is deeply depend on both the frequency response of the pressure sensor and the water depth at the sensor. In this study, a relatively accurate surface displacement can be recovered when the frequency response function is cut off at the frequency corresponding to kh=3.0 where k is a wave number at the depth of h. The frequency response function in the region higher than the cut-off-frequency is set constant to be the value at the cut-off-frequency. ii) The transformed surface displacements by LCM are affected by the small waves of short periods included in the measured pressure. It is found that pressure variation whose local frequency is higher than kh=1.5 has to be neglected to recover surface displacement sufficiently. iii) In IWM, the linear pressure response function is usually utilized by multiplying a coefficient N which is a function of the frequency (or kh) and takes a value around unity. However, in this study, a constant value of N(=1.0) gives a relatively accurate recovery of surface displacements.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3101-3103
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• 2016

Background: According to the most recent estimation of GLOBOCAN, Cambodia has the highest incidence and mortality rate of cervical cancer in Southeast Asia. A screen-and-treat strategy using visual inspection with acetic acid (VIA test) and cryotherapy has been implemented in Cambodia's national cervical cancer screening program since 2013. However, where resources are available, cervical cytology with or without high-risk HPV DNA testing is the preferred screening method used in this country. Aim: This study aims to calculate the prevalence of abnormal cervical cytology and explain the possible factors contributing to a reduced quality of cervical cytology among women participating in a hospital-based cervical cancer screening program in Cambodia. Materials and Methods: A descriptive study was conducted using information from the cytology and pathology database in the Department of Pathology of Calmette Hospital between January 2012 and December 2015. Prevalence of abnormal cervical cytology, based on the Bethesda 2001 classification, was calculated. Data on the adequacy of cytological specimens were analyzed in order to explain the factors contributing to a reduced quality of cervical cytology interpretation. Results: Among 6,207 women who participated in the cervical cancer screening program at Calmette Hospital during 2012 and 2015, 388 (6.25%) had abnormal cytology, which could be classified into Atypical Squamous Cells of Undetermined Significance (92 cases; 1.48%), Atypical Squamous Cells - Cannot Exclude High-Grade Intraepithelial Lesion (13 cases; 0.21%), Atypical Glandular Cells (11 cases; 0.18%), Low-Grade Squamous Intraepithelial Lesion (221 cases; 3.56%), High-Grade Squamous Intraepithelial Lesion (26 cases; 0.42%), and Squamous Cell Carcinoma (25 cases; 0.40%). Unsatisfactory smears made up 12.2% of the total cases. The most frequently identified factor leading to unsatisfactory smears was the absence of cells from the transformation zone. Conclusions: The present study showed an overall prevalence of abnormal cervical cytology of 6.25%, which is comparable to that in many large population-based studies in the Asia Pacific region. Nevertheless, the remarkably high rate of unsatisfactory smears in this study justifies further improvement in specimen sampling among Cambodian gynecologists.

• The Korean Journal of Mycology
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• v.23 no.2 s.73
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• pp.129-138
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• 1995

DNA fragment being able to restore in vitro activity of ${\beta}-1,3-glucan$ synthase was cloned by transformation of the Saccharomyces cerevisiae LP353 mutant strain with genomic library constructed in the YCp50. For the selection of transformants which showed no detectable phenotype linked to recovery of the defect in ${\beta}-1,3-glucan$ synthase activity, the colony autoradiography was succesfully applied. The restriction map of the cloned DNA fragment, which is 8.5-kb in length, was constructed. Both the YEplac195 and the YCp50 carrying the 8.5-kb fragment increased ${\beta}-1,3-glucan$ synthase activity of LP353 by two fold. Neither the YEplac195 nor the YCp50 carrying the 8.5-kb DNA fragment, however, complemented the temperature-dependent osmotic sensitivity which is another distinctive phenotype of LP353. Subcloning experiments indicated that a functional region was located in 4.8-kb BglII-KpnI fragment. The 4.8-kb fragment was also able to increase the level of ${\beta}-1,3-glucan$ content in cell wall as well as the resistance of cells to cell wall lytic enzyme, ${\beta}-1,3-glucanase$. The growth rate of the LP353 with 4.8-kb fragment was almost same as that of wild type strain in liquid medium with 1.2 M sorbitol at nonpermissive temperature. Taken these results together, the 4.8-kb fragment seemed to contain the BGS2 gene for ${\beta}-1,3-glucan$ synthase activity in yeast S. cerevisiae.

• The KIPS Transactions:PartB
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• v.14B no.4
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• pp.249-254
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• 2007

A mobile robot with various types of sensors and wireless camera is introduced. We show this mobile robot can detect objects well by combining the results of active sensors and image processing algorithm. First, to detect objects, active sensors such as infrared rays sensors and supersonic waves sensors are employed together and calculates the distance in real time between the object and the robot using sensor's output. The difference between the measured value and calculated value is less than 5%. We focus on how to detect a object region well using image processing algorithm because it gives robots the ability of working for human. This paper suggests effective visual detecting system for moving objects with specified color and motion information. The proposed method includes the object extraction and definition process which uses color transformation and AWUPC computation to decide the existence of moving object. Shape information and signature algorithm are used to segment the objects from background regardless of shape changes. We add weighing values to each results from sensors and the camera. Final results are combined to only one value which represents the probability of an object in the limited distance. Sensor fusion technique improves the detection rate at least 7% higher than the technique using individual sensor.

• Journal of Plant Biotechnology
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• v.34 no.4
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• pp.347-354
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• 2007

Commercialization of genetically modified (GM) plants will be required the assessment of risks associated with the release of GM plants that should include a detailed risk assessment of their impacts in human health and the environment. Prior to GM plant release, applicants should provide the information on GM crops for approval. We carried out this study to provide the molecular data for risk assessment of the GM Chinese cabbage plants with insect-resistance gene, modified CryIAc, which we obtained by Agrobacterium-transformation. From the molecular analysis with GM Chinese cabbage, we confirmed the transgene copy number and stability, the expression of the transgene, and integration region sequences between the transgene and the Chinese cabbage genome. Based on the unique integration DNA sequences, we designed specific primer set to detect GM Chinese cabbage and set up the GM cabbage detection method by qualitative PCR analysis. Qualitative analysis with GM Chinese cabbage progenies analysis was revealed the same as the result of herbicide treatment. Our results provided the molecular data for risk assessment analysis of GM Chinese cabbage and demonstrated that the primer set proposed could be useful to detect GM Chinese cabbage.

• Journal of Plant Biotechnology
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• v.37 no.1
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• pp.102-109
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• 2010

Fructan has been found to accumulate in various tissues during periods when light levels increased carbon fixation where low temperatures reduced growth rates while photosynthesis continued. In this study, we have cloned 1-sucrose:sucrose fructosyl transferase(1-sst) and 1-fructan: fructan fructosyl transferase (1-fft, a key enzyme for the synthesis of fuctan) from Jerusalem Artichoke (Helianthus tuberosus L.). The recombinant vector with 1-sst and 1-fft has been constructed under the control of 35S promoter of KJGV-B2 vector and transgenic plants obtained by Agrobacterium tumefaciens LBA4404. PCR analysis carried out on the putative transgenic plants for amplification of the coding region of specific gene (1-sst, 1-fft), and HPT genes. Transgenic lines carrying of 1-sst and 1-fft were confirmed for integration into the rice genome using Southern blot hybridization and RT-PCR. The transgenic plants in $T_2$ generation were selected and expression pattern analysis revealed that 1-sst and 1-fft were stable. This analysis confirmed the presence of low-molecular-weight fructan in the seedling of the transgenic rices. Therefore, cold tolerance and carbohydrate metabolism will be possible to develop resistant plants using the transgenic rice.