• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.09a
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• pp.368-375
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• 2003

The objectives of this study were to provide experimental data on the behavior of interlocking spiral columns under cyclic loading, to compare the performance of columns with interlocking spirals to columns with U-type hoops with hook, to study the flexural detailing of interlocking spirals and other transverse steel configurations as the transverse reinforcement The oblong columns with interlocking spirals and with hooked U-type hoops and cross-ties better seismic performance than the rectangular columns with rectangular hoops and cross-ties. The oblong columns with hooked U-type hoops and cross-ties showed better seismic performance than the rectangular columns with rectangular hoops and cross-ties. And this research were to make recommendations for the design of bridge columns incorporating interlocking spirals and U-type hoops with hook as the transverse reinforcement.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.10 s.241
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• pp.1075-1082
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• 2005

The characteristics of longitudinal dispersion enhancement by the flow oscillation are numerically studied according to various groove geometries in a 2-D channel in the present study. The length of expanded section l$_{1}$/h$_{1}$ is varied from 0 to 8.75. The oscillating flow condition is given at both side ends, i.e., u = Asin ($2{\pi}ft$) The non-dimensional temperatures at both side ends are set to zero. The bottom and top walls are adiabatic. The local heat sources are located at the middle of the groove wall. In order to solve the governing equations, the SIMPIER algorithm is employed. The present results indicate that maximum longitudinal thermal dispersion can be achieved when the area ratio of the expanded section to the contracted section in the grooved channel becomes 1.

• Applied Science and Convergence Technology
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• v.23 no.3
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• pp.103-112
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• 2014

The Korea Research Institute of Standards and Science (KRISS) has three major vacuum systems: an ultrasonic interferometer manometer (UIM; Section II, Figs. 1 and 2) for a low vacuum, a static expansion system (SES; Section III, Figs. 3 and 4) for a medium vacuum, and an orifice-type dynamic expansion system (DES, Section IV, Figs. 5 and 6) for high and ultra-high vacuum systems. For each system, explicit measurement model equations with multiple variables are given. According to ISO standards, all of these system variable errors were used to calculate the expanded uncertainty (U). For each system, the expanded uncertainties (k = 1, confidence level = 95%) and relative expanded uncertainty (expanded uncertainty/generated pressure) levels are summarized in Table 4. Within the uncertainty limits, our bilateral and key comparisons [CCM.P-K4 (10 Pa to 1 kPa)] are extensive and in good agreement with those of other nations (Fig. 8 and Table 5).

• Membrane Journal
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• v.2 no.2
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• pp.104-111
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• 1992

A curved channel duct is designed, built and used specifically to produce Dean vortices as a result of flow around a $180^{\circ}C$ curve. We present evidence using optical reflection of the existmace of the vortices in the curved section and following flat section. Also, three different feed soludons(DI water, a monodispersed styrene-divinyl-benzene latex particle suspension and a yeast suspension) were used to determine the effectiveness of Dean instabilities to destabilize polarization layers. For each suspension, the flux data were compared as a function of time for flow conditions with and without Dean vortices, for a $0.2{\mu}m$ microfiltration membrane. Any permeation flux improvement was not sustained for $2.0De_c$ due to the vortex-decay in the flat section after the curved channel, but a 15~30% permeation improvement was obtained for $3.8De_c$.

• Geosystem Engineering
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• v.21 no.5
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• pp.262-272
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• 2018

The U-statistic method is one of the most important structural methods to separate the anomaly from background. It considers the location of samples and carries out the statistical analysis of the data without judging from a geochemical point of view and tries to separate subpopulations and determine anomalous areas. In the present study, 3D U-statistic method has been applied for the first time through the three-dimensional (3D) modeling of an ore deposit. In order to achieve this purpose, 3D U-statistic is applied on the data (Fe grade) resulted from the drilling network in Baghak mine, central part of the Sangan iron mines (in Khorassan Razavi Province, Iran). Afterward, results from applying 3D U-statistic method are used for 3D modeling of the iron mineralization. Results show that the anomalous values are well separated from background so that the determined samples as anomalous are not dispersed and according to their positioning, denser areas of anomalous samples could be considered as anomaly areas. And also, final results (3D model of iron mineralization) show that output model using this method is compatible with designed model for mining operation. Moreover, seen that U-statistic method in addition for separating anomaly from background, could be very efficient for the 3D modeling of different ore type.

• Korean Journal of Head & Neck Oncology
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• v.13 no.2
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• pp.206-212
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• 1997

H$\"{u}$rthle cell neoplasm of the thyroid gland is an uncommon, but potentially malignant lesion. However, in many instances, the malignant potential of the H$\"{u}$rthle cell neoplasm is very difficult to judge histologically. For this reason, the biologic behavior of this tumor and its optimal treatment have come under considerable debate in recent years. In order to review the clinicopathologic features of the H$\"{u}$rthle cell neoplasm and to determine its optimal treatment modalities, we studied 26 patients with path logical proof of H$\"{u}$rthle cell tumor from January 1987 to September 1997. We also performed an immunohistochemical study using the monoclonal antibodies against antigen CD34 for the angiogenic activity of this tumor and evaluated the differences of microvessel density(MVD) between benign and malignant tumors. The age of the patients ranged from 1 to 71 years with a mean of 44.2 years. There were 6 males and 20 females(M : F= 1 : 3.3). The accuracies of fine needle aspiration biopsy and frozen section were very low; 6.3% and 34.8%, respectively. There were 20 benign tumors and 6 malignant tumors(23.1%). All the malignant tumors were microinvasive(intermediate) type which had minimal capsular invasion and most of them(5 cases) were diagnosed postoperatively. Any specific clinicopathologic differences were not seen between benign and intermediate groups. Most of the cases had conservative surgeries(15 ipsilateral lobectomy-isthmusectomy, 7 subtotal thyroidectomy) while total thyroidectomy was performed in 4 cases. Of the cases with malignant tumor, 2 had ipsilateral lobectomy-isthmusectomy, 3 had subtotal thyroidectomy and the remaining 1 had total thyroidectomy. Mean size of the tumors was 3.0 cm(0.1- 8.5 cm) in the greatest diameter and multiple tumors were seen in 6 cases(23.1 %). During the follow-up period, only one recurrence(3.8%) of benign tumor occurred but distant metastasis or cause-specific death was seen in the benign or intermediate groups. Mean MVDs of the benign(n=13) and intermediate(n=6) groups were $121.7{\pm}35.3$ and $114.3{\pm}31.7$, respectively and there was no statistical significance between them. In conclusion, because of the low accuracies of fine needle aspiration biopsy and frozen section for the H$\"{u}$rthle cell neoplasm, the extent of surgery could be individualized based on permanent pathologic examination; Conservative surgery would be adequate for patients with benign or intermediate H$\"{u}$rthle cell neoplasm and total or near-total thyroidectomy for those with definite malignancy.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.82-82
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• 2003

Offspring have been produced from somatic cells in a number of species. This biotechnology introduced a new phenomenon in reprogramming and differentiation of somatic cell, namely totipotency. However, birth of oversized calves and perinatal abnormalities such as increased gestation length, lack of spontaneous parturition, higher incidence of dystocia, and reduced perinatal viability of offspring are frequently observed in pregnancies of cloned bovine fetuses. Disturbance of feto-placenta has been proposed as likely causes for abnomal growth. However. Little is known the mechanism responsible for the perinatal problems. Therefore, we focused on gestation length in somatic cell nuclear recipient cows. To solve this issues, placental tissues of control and cloned bovine were obtained by a cesarean section (C-section) before 5 days of paturition. Total RNA from control and cloned bovine placenta was extractd by TRIzol reagent. GeneFishing DEG kits (Seegene) were used to identify differentially expression genes. Total RNA (3 ug) were synthesized by M-MLV reverse transcriptase (200 u/ul) with 10 uM dT-annealing control primer (ACP1) at 42C for 90 min. Then, first-strand cDNA (50 ng) was amplified using the 5 uM arbitary ACP (1-20) and 10 uM dT-ACP2 primers. Some specific expression genes were amplified, Now, we are cloning and sequencing. These finding strongly can be support to solve the problems for parturition delay in nuclear transfer cows, suggest that placenta specific proteins are key indicators for the aberration of gestation and placental function in cows.

• Journal of Advanced Navigation Technology
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• v.27 no.6
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• pp.815-820
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• 2023

In this paper, the design method of a miniaturized chipless RFID tag using a modified bent H-shaped slot was proposed. The proposed modified bent H-shaped slot was appended on the rectangular conductor plate printed on one side of a 20 mm × 50 mm FR4 substrate with a thickness of 0.8 mm. The resonant dip frequency of the bistatic RCS for the proposed modified bent H-shaped slot was compared with the cases when the H-shaped, U-shaped slot, and bent H-shaped slots were added, respectively, on the conductor plate. The simulated resonant dip frequencies for H-shaped, U-shaped, and bent H-shaped slots were 5.907 GHz, 4.918 GHz, and 4.364 GHz, respectively. When the proposed modified bent H-shaped slot was added, the resonant dip frequency was decreased to 3.741 GHz, and, therefore, the slot length was reduced by 36.7% compared to the H-shaped slot case. Experiment results show that the resonant dip frequency of the fabricated modified bent H-shaped slot was 3.9 GHz.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2006.04a
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• pp.373-373
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• 2006

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2010.05a
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• pp.670-671
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• 2010