• Journal of the Earthquake Engineering Society of Korea
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• v.24 no.5
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• pp.197-209
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• 2020

Evidence of liquefaction during the 2017 Pohang earthquake has highlighted the urgent need to evaluate the current seismic design standard for liquefaction in Korea, particularly the liquefaction triggering standard. With the simplified method, which is the most popular method for evaluating liquefaction triggering, the factor of safety for liquefaction triggering is calculated via the cyclic stress ratio (CSR) and the cyclic resistance ratio (CRR). The parameters in the CSR and CRR have undergone changes over time based on new research findings and lessons learned from liquefaction case-histories. Hence, the current design standard for liquefaction triggering evaluation in Korea should also reflect these changes to achieve seismic safety during future earthquakes. In this study, liquefaction susceptibility criteria were discussed initially and this was followed by a review of the current liquefaction triggering codes/guidelines in other countries and Korea. Next, the parameters associated with the CSR such as the maximum ground acceleration, stress reduction factor, magnitude scaling factor, and overburden correction factor were discussed in detail. Then, the evaluation of the CRR using the SPT N-value and CPT qc-value was elaborated along with overburden and clean-sand correction factors. Based on this review of liquefaction triggering evaluation standards, recommendations are made for improving the current seismic design standard related to liquefaction triggering in Korea.

• Clinical and Experimental Reproductive Medicine
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• v.42 no.2
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• pp.67-71
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• 2015

Objective: Elevated serum progesterone (P) levels on triggering day have been known to affect the pregnancy rate of in vitro fertilization (IVF). This study aimed to identify the possible factors influencing serum P levels on triggering day in stimulated IVF cycles. Methods: Three hundred and thirty consecutive fresh IVF cycles were included in the study. All cycles were first attempts and were performed in a single infertility center. The indications for IVF were male factor infertility (n=114), ovulatory infertility (n=84), endometriosis (n=61), tubal infertility (n=59), unexplained infertility (n=41), and uterine factor infertility (n=39). A luteal long protocol of a gonadotropin-releasing hormone (GnRH) agonist (n=184) or a GnRH antagonist protocol (n=146) was used for pituitary suppression. Ovarian sensitivity was defined as the serum estradiol level on triggering day per 500 IU of administered gonadotropins (OS[a]) or the retrieved oocyte number per 500 IU of administered gonadotropins (OS[b]). Results: Univariate analysis revealed that the serum P level on triggering day was associated with the serum estradiol level on triggering day (r=0.379, p<0.001), the number of follicles ${\geq}14mm$ (r=0.247, p<0.001), the number of retrieved oocytes (r=0.384, p<0.001), and ovarian sensitivity (OS[a]: r=0.245, p<0.001; OS[b]: r=0.170, p=0.002). The woman's age, body mass index, antral follicle count, and basal serum follicle stimulating hormone and estradiol levels were not associated with serum P level on triggering day. The serum P level on triggering day did not show significant variation depending on the type or cause of infertility, pituitary suppression protocol, or the type of gonadotropins used. Conclusion: The serum P level on triggering day was closely related to the response to ovarian stimulation.

• Clinical and Experimental Reproductive Medicine
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• v.43 no.4
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• pp.240-246
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• 2016

Objective: The study aimed to investigate the efficacy of intrauterine instillation of granulocyte colony-stimulating factor (G-CSF) on the day of ovulation triggering or oocyte retrieval in infertile women with a thin endometrium. Methods: Fifty women whose endometrial thickness (EMT) was ${\leq}8mm$ at the time of triggering during at least one previous in vitro fertilization (IVF) cycle and an index IVF cycle were selected. On the day of triggering (n = 12) or oocyte retrieval (n = 38), $300{\mu}g$ of G-CSF was instilled into the uterine cavity. Results: In the 50 index IVF cycles, the mean EMT was $7.2{\pm}0.6mm$ on the triggering day and increased to $8.5{\pm}1.5mm$ on the embryo transfer day (p< 0.001). The overall clinical pregnancy rate was 22.0%, the implantation rate was 15.9%, and the ongoing pregnancy rate was 20%. The clinical pregnancy rate (41.7% vs. 15.8%), the implantation rate (26.7% vs. 11.7%), and the ongoing pregnancy rate (41.7% vs. 13.2%) were higher when G-CSF was instilled on the triggering day than when it was instilled on the retrieval day, although this tendency was likewise not statistically significant. Aspects of the stimulation process and mean changes in EMT were similar in women who became pregnant and women who did not. Conclusion: Intrauterine instillation of G-CSF enhanced endometrial development and resulted in an acceptable pregnancy rate. Instillation of G-CSF on the triggering day showed better outcomes. G-CSF instillation should be considered as a strategy for inducing endometrial growth and good pregnancy results in infertile women with a thin endometrium.

• Geomechanics and Engineering
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• v.22 no.4
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• pp.319-328
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• 2020

This paper investigates the effect of the width of failure and tension crack (TC) on the stability of cohesive-frictional soil slopes in three dimensions. Working analytically, the slip surface and the tension crack are considered to have spheroid and cylindrical shape respectively, although the case of tension crack having planar, vertical surface is also discussed; the latter was found to return higher safety factor values. Because at the initiation of a purely rotational slide along a spheroid surface no shear forces develop inside the failure mass, the rigid body concept is conveniently used; in this respect, the validity of the rigid body concept is discussed, whilst it is supported by comparison examples. Stability tables are given for fully drained and fully saturated slopes without TC, with non-filled TC as well as with fully-filled TC. Among the main findings is that, the width of failure corresponding to the minimum safety factor value is not always infinite, but it is affected by the triggering factor for failure (e.g., water acting as pore pressures and/or as hydrostatic force in the TC). More specifically, it was found that, when a slope is near its limit equilibrium and under the influence of a triggering factor, the minimum safety factor value corresponds to a near spherical failure mechanism, even if the triggering factor (e.g., pore-water pressures) acts uniformly along the third dimension. Moreover, it was found that, the effect of tension crack is much greater when the stability of slopes is studied in three dimensions; indeed, safety factor values comparable to the 2D case are obtained.

• The KIPS Transactions:PartD
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• v.8D no.1
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• pp.10-23
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• 2001

Transactions in real-time active databases have the notion of activeness where transactions are generated by external effects and another transaction. In this paper, we propose the multi version concurrency control algorithm for real-time active transactions. A real-time active transaction has a timing constraint in the form of a deadline until which the user wants to complete the transaction, and is characterized by triggering relationships which mean that association between a transaction that triggers the execution of another transaction and the triggered transaction. The triggering relationship is an important factor to resolve data conflicts among real-time active transactions. The proposed concurrency control mechanism resolves data conflicts by considering triggering relationships between conflicting transactions as well as priorities and precedence relationships. The conflict resolution mechanism considers association types of the triggering relationship such as abort and commit dependency, and then resolves data conflicts in favor of higher priority transactions. We also present the experimental results of our algorithm comparing other real-time active concurrency control algorithms.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.600-608
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• 2013

Amide analogs of tridecapeptide ${\alpha}$-factor (WHWLQLKPGQPMYCONH$_2$) of Saccharomyces cerevisiae, in which Trp at position 1 and 3 were replaced with other residues, were synthesized to ascertain whether cooperative interactions between two Trp residues occurred upon binding with its receptor. Analogs containing Ala or Aib at position 3 of the peptide $[Ala_3]{\alpha}$-factor amide (2) and $[Aib_3]{\alpha}$-factor amide (5) exhibited greater decreases in bioactivity than analogs with same residue at position one $[Ala^1]{\alpha}$-factor amide (1) and $[Aib^1]{\alpha}$-factor amide (4), reflecting that $Trp^3$ may plays more important role than $Trp^1$ for agonist activity. Analogs containing Ala or Aib in both position one and three 3, 6 exhibited complete loss of bioactivity, emphasizing both the essential role and the combined role of two indole rings for triggering cell signaling. In contrast, double substituted analog with D-Trp in both positions 9 exhibited greater activity than single substituted analog with D-Trp 8 or deleted analog 7, reflecting the combined contribution of two tryptophane residues of ${\alpha}$-factor ligand to activation of Ste2p through interaction with residue $Tyr^{266}$ and importance of the proper parallel orientation of two indole rings for efficient triggering of signal G protein coupled activation. Among ten amide analogs, $[Ala^{1,3}]{\alpha}$-factor amide (3), $[Aib^{1,3}]{\alpha}$-factor amide (6), [D-$Trp^3]{\alpha}$-factor amide (8) and [des-$Trp^1,Phe^3]{\alpha}$-factor amide (10) were found to have antagonistic activity. Analogs 3 and 6 showed greater antagonistic activity than analogs 8 and 10.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1704-1706
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• 2002

With increasement of use in electricity energy, quality of electric apparatus has been recognized as important factor in distribution and transmission line. Especially In laboratories, lightning and switching impulse performances of electric apparatus have been carrying out by impulse voltage generator (IVG), simulated into lightning and switching surge circuit. In this paper, we describe triggering system of impulse voltage generator(IVG) for extra high voltage, which has been newly designed.

• The Korean Journal of Pain
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• v.20 no.2
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• pp.174-180
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• 2007

Background: The diagnosis of trigeminal neuralgia (TN) is based on only clinical criteria. The purpose of this study was to estimate the clinical manifestations of TN patients treated at our pain clinic. Methods: A total of 341 patients with TN from Jan. 2004 to Dec. 2006 was evaluated the intensity, site, and onset of pain, facial sensation, duration of pain attack, pain free interval, triggering factors, and effects of the previous treatments with TN specific questionnaire and interview at the first visit of our pain clinic. Results: About 80% of the patients were over 50 years of age and 256 (75%) patients were women. Average durations from first attack of their pain and from current pain attack were 7 years and 16 weeks, respectively. The two most frequently involved trigeminal nerve branches were maxillary (40%) and mandibular (39%) branches. Three quarters of the total patients experienced only paroxysmal pain that lasted less than one minute. About 90% of patients had pain free period at least one time. Most common triggering factors were chewing (88%), brushing teeth (82%), washing face (79%), and talking (70%). Only 16 patients (5%) had no previous treatment and the others had more than one treatment, such as medication (68%) and interventional procedures (35%). The most common reasons for early discontinuation of carbamazepine were dizziness, ataxia, and vomiting. Conclusions: TN has specific clinical features of pain, which should be considered at diagnosis.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.185-190
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• 2005

In this study, a probabilistic prediction model for debris flow occurrence was developed using a logistic regression analysis. The model can be applicable to metamorphic rocks and granite area. In order to develop the prediction model, detailed field survey and laboratory soil tests were conducted both in the northern and the southern Gyeonggi province and in Sangju, Gyeongbuk province, Korea. The six landslide triggering factors were selected by a logistic regression analysis as well as several basic statistical analyses. The six factors consist of two topographic factors and four geological and geotechnical factors. The model assigns a weight value to each selected factor. The verification results reveal that the model has 86.5% of prediction accuracy. Therefore, it is possible to predict landslide occurrence in a probabilistic and quantitative manner.

• Proceedings of the Botanical Society of Korea Conference
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• 1996.07a
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• pp.10-18
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• 1996

Recently, we have reported a rice MADS-box gene, OsMADS1, as a molecular factor triggering flower formation; this has been well studied in a heterologous system (Chung et al., 1994). In order to study whether the OsMADS1 homolog exists in other plant species, the OsMADS1 cDNA was used as a probe to screen a tobacco cDNA library, and a potential homolog, NtMADS3, was isolated. Sequence analysis revealed that the gene shares 56.1% identity in whole amino acids with OsMADS1. Like OsMADS1, the NtMADS3 gene starts to express at a very early stage of flower development, and the expression continues up to flower maturation. In the tobacco flower, the gene is expressed in whorl 2,3 and 4, corresponding to the petal, stamen, and carpel, respectively. Upon ectopic expression in the homologous system, NtMADS3 caused a trasition from inflorescence shoot meristem into floral meristem, reducing flowering time dramatically. These phenotypes strongly suggest the NtMADS3 gene is the OsMADS1 homolog of tobacco. Hybrids between the OsMADS1 and the NtMADS3 plants were also generated. The hybrids flowered even earlier than these two transgenic plants. The detailed studies are discussed here.