• Clinical and Experimental Reproductive Medicine
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• v.24 no.3
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• pp.361-368
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• 1997

A total of 55 patients with various etiologies of infertility particitated in a study comparing two regimens of controlled ovarian hyperstimulation (COH) with GnRH agonists and gonadotropins. Nineteen patients were given an ultra-short stimulation protocol when the agonist was administered for 3 day from Day 2 of the cycle. The remaining 36 patients were given a long stimulation protocol when the agonist was administered from the mid-luteal phase of the cycle preceding the stimulation cycle. The mean number of gonadotropins used per patient was not different between two groups. No significant differences were found in the mean number of oocytes recovered, fertilization rate and embryo cleavage rate between two groups. Pregnancy and delivery rates were higher in ultra-short protocol than in long protocol, but these were not significant. These results suggest that an ultra-short protocol is as effective as a long protocol in in-vitro fertilization and embryo transfer.

• Clinical and Experimental Reproductive Medicine
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• v.30 no.1
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• pp.95-103
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• 2003

Objective : To assess and compare the clinical outcomes between GnRH agonist long protocol and GnRH antagonist short protocol in oocyte donation program. Materials and Methods: Of total 18 oocyte donation cycles, controlled ovarian hyperstimulation (COH) were performed with GnRH agonist long protocol and GnRH antagonist short protocol in initial 9 cycles and later 9 cycles, respectively. Oral estradiol valerate and progesterone in oil we re administrated to all recipients for endometrial preparation. Oral estradiol administration was started from donor cycle day 1 after full shut down of gonadal axis with GnRH agonist in patients with ovarian function. Progesterone was injected from oocyte retrieval day of donor initially, then continuously till pregnancy 12 weeks if pregnancy was ongoing. We compared the parameters of clinical outcomes, such as number of the retrieved oocytes, fertilization rate, high grade embryo production rate, clinical pregnancy rate, implantation rate, ongoing pregnancy rate, COH duration, total gonadotropin dose for COH between GnRH agonist long protocol group and GnRH antagonist group. Statistical analysis was performed using Mann-Whitney test, p<0.05 was considered as statistically significant. Results: The number of retrieved oocytes, fertilization rate, high grade embryo production rate, clinical pregnancy rate, implantation rate, ongoing pregnancy rate were $14.89{\pm}7.83$, 81%, 64%, 78%, 31%, 78%, respectively in GnRHa long protocol group and $11.22{\pm}8.50$, 79%, 64%, 67%, 34%, 56%, respectively in GnRH antagonist group. There was no significant differences in parameters of clinical outcomes between 2 groups (all p value >0.05). Duration and total gonadotropin dose for COH were $10.94{\pm}1.70$ days and $43.78{\pm}6.8$ vials in 18 cycles, $12.00{\pm}1.73$ days and $48.00{\pm}6.93$ vials in agonist group, $9.88{\pm}0.78$ days and $39.55{\pm}3.13$ vials in antagonist group, respectively. In GnRH agonist long protocol group, significantly longer duration and higher gonadotropin dose for COH were needed (p=0.012). Conclusion: In oocyte donation program, clinical outcomes from controlled ovarian hyperstimulation with GnRH antagonist were comparable to those from GnRH agonist long protocol group, so controlled ovarian hyperstimulation with GnRH antagonist may be effective as GnRH agonist long protocol. At least there may not be harmful effects of GnRH antagonist on oocyte development and quality.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.3
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• pp.239-244
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• 2010

Objective: The objective of this retrospective study was to compare the in vitro fertilization (IVF) outcomes of gonadotropinreleasing hormone (GnRH) agonist and GnRH antagonist protocols in poor responders. Methods: A total of 172 cycles in subjects with less than 5 oocytes retrieved treated with either GnRH agonist long protocols or antagonist protocols were included. The outcome variables such as numbers of growing follicles and retrieved oocytes, and the fertilization rate were evaluated as the main outcome measures. Results: There was no difference in regard to the numbers of growing follicles and oocytes, and fertilization rate between the two groups. $E_2$ level on Day 7/8, mean gonadotropin dose, and the days of stimulation were shown to be statistically different (p<0.01, respectively). Conclusion: Considering that similar results were observed with less time and gonadotropin dose, GnRH antagonist protocol may be considered as a preferable choice over GnRH agonist protocols in poor responders.

• Journal of the Institute of Convergence Signal Processing
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• v.12 no.1
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• pp.44-49
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• 2011

The need of data transmission in oceans and other underwater mediums are increasing day by day, so as the research. The underwater medium is very different from that of air. Propagation of electromagnetic wave in water or underground is very difficult because of the conductivity of the propagation materials. In this case, we usually use acoustic signals as ultrasonic but, they are not easy to transfer long distance with coherent method because of time varying multipaths, Doppler effects and attenuations. So, we use non-coherent methods such as FSK or ASK to communicate between long distances. But, as the propagation speed of acoustic wave is very slow, BW of the channel is narrow. It is very hard to guaranty the enough speed for the transmission of digital image data. In previous studies, we proposed this data communication protocol theoretically. In this paper, an underwater channel is modeled and this protocol is tested in this channel condition. The results show that the protocol is 4-6 times faster than ASK. Some relations and results are shown depending on the data length, channel length, bit rate etc.

• Journal of information and communication convergence engineering
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• v.2 no.4
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• pp.214-218
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• 2004

In this paper, we have analyzed TCP performance over wireless correlated fading links with and without Snoop protocol. For a given value of the packet error rate, TCP performance without Snoop protocol is degraded as the fading is getting fast (i.e. the user moves fast). When Snoop protocol is introduced in the base station, TCP performance is enhanced in most wireless environments. Especially the performance enhancement derived from using Snoop protocol is large in fast fading channel. This is because packet errors become random and sporadic in fast fading channel and these random packet errors (mostly single packet errors) can be compensated efficiently by Snoop protocol's local packet retransmissions. But Snoop protocol can't give a large performance improvement in slow fading environments where long bursts of packet errors occur. Concerning to packet error rate, Snoop protocol results in the highest performance enhancement in the channel with mid-high values of packet error rate. This means Snoop protocol cannot fully fulfill its ability under too low or too high packet error rate environments.

• Clinical and Experimental Reproductive Medicine
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• v.18 no.2
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• pp.201-208
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• 1991

Recently the application of gonadotropin-releasing hormone (GnRH) agonist to superovulation in previous poor responders has resulted in the improved outcomes after in vitro fertilization (IVF) outcome. However, poor responders with poor estradiol $(E_2)$ rise or single dominant follicle are a particularly challenging group. Recent reports have also shown that patients with higher basal serum follicle stimulating hormone (FSH) level, result in poorer ovarian response and lower pregnancy rate. Analysis of the differences of superovulation outcomes according to the different protocols of GnRH agonist, long (L, n = 18) and short (S, n = 16) protocols, in patients with high basal FSH levels (>20mIU/ml) were undertaken at Seoul National University Hospital from June to October 1990. The administration of GnRH agonist was begun on day 21 of the cycle in long protocol, and on day 2 in short protocol. Ages of patients and husbands, basal FSH and luteinizing hormone (LH) levels and FSH/LH ratio did not differ significantly. Types and causes of infertility were evenly distributed. Whereas the duration of stimulation and the amounts of gonadotropins administered were significantly reduced in short protocol, the numbers of oocytes retrieved and cleaved, the cleavage rate and the number of embryos transferred were higher in long protocol without statistical signifieance. The pregnancy rate per ET was 16.7% (2/12) in short protocol, and 17.6% (3/17) in long protocol. These data suggest that both protocols result in the similar superovulation outcomes in patients with higher basal serum FSH levels.

• Clinical and Experimental Reproductive Medicine
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• v.29 no.4
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• pp.251-258
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• 2002

Objective : The aim of this study was to evaluate the outcomes of the GnRH antagonist (Cetrotide) minimal stimulation protocol comparing with GnRH agonist combined long step down stimulation protocol in PCOS patients. Materials and Method: From Apr 2001 to May 2002, 22 patients (22 cycles) were performed in controlled ovarian hyperstimulation using by GnRH antagonist and GnRH agonist for PCOS patients. GnRH antagonist (Cetrotide) combined minimal stimulation protocol was administered in 10 patients (10 cycles, Study Group) and GnRH agonist long step down stimulation protocol was administered in 12 patients (12 cycles, Control Group). We compared the pregnancy rate/cycle, total FSH (A)/cycle, Retrieved oocyte/cycle, the incidence of ovarian hyperstimulation syndrome, multiple pregnancy rate between the two groups. Student-t test were used to determine statistical significance. Statistical significance was defined as p<0.05. Results: Group of GnRH antagonist (Cetrorelix) minimal stimulation protocol produced fewer oocytes (6.4 versus 16.3 oocytes/cycle) using a lower dose of FSH (22.2 versus 36.1 Ample/cycle) and none developed OHSS and multiple pregnancy. Although the trends were in favour of the GnRH antagonist (Cetrorelix) protocol, the differences did not reach statistical significance. This was probably due to small sample size. Conclusion: The use of GnRH antagonist reduce the risk of ovarian hyperstimulation and multiple pregnancy. We suggest that GnRH antagonist might be alternative controlled ovarian hyperstimulation method, especially in PCOS patients who will be ovarian high response.

• International journal of advanced smart convergence
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• v.6 no.3
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• pp.53-58
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• 2017

A WSN (Wireless Sensor Network) is a network that is composed of wireless sensor nodes. There is no restriction on the place where it can be installed because it is composed wirelessly. Instead, sensor nodes have limited energy. Therefore, to use the network for a long time, energy consumption should be minimized. Several protocols have been proposed to minimize energy consumption, and the typical protocol is the LEACH protocol. The LEACH protocol is a cluster-based protocol that minimizes energy consumption by dividing the sensor field into clusters. Depending on how you organize the clusters of sensor field, network lifetimes may increase or decrease. In this paper, we will improve the network lifetime by improving the cluster head selection method in LEACH Protocol.

• Journal of Korea Society of Digital Industry and Information Management
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• v.8 no.1
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• pp.47-53
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• 2012

Sensor networks and car networks that have different structure from that of conventional TCP/IP network require extreme network environment due to frequent change of connectivity. Because such extreme network environment has characteristics like unreliable link connectivity, long delay time, asymmetrical data transfer rate, and high error rate, etc., it is difficult to perform normally with the conventional TCP/P-based routing. DTNs (delay and disruption tolerant network) was designed to support data transfer in extreme network environment with long delay time and no guarantee for continuous connectivity between terminals. This study suggests an algorithm that limits the maximum number of copying transferred message to L by improving the spray and wait routing protocol, which is one of the conventional DTNs routing protocols, and using the azimuth and density data of the mobile nods. The suggested algorithm was examined by using ONE, a DTNs simulator. As a result, it could reduce the delay time and overhead of unnecessary packets compared to the conventional spray and wait routing protocol.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.621-624
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• 2017

In this paper, we propose a protocol synchronizing to packet trains in a underwater acoustic networks with limitations such as long propagation delay, low data rate, high packet loss. The proposed protocol employs an one-way communication scheme to calculate packet arrival time differences of consecutively transferred packets and minimizes uncertain variation effect of long propagation delay. Simulation results shows the superiority of our protocol, compared with a previously proposed one under the given network conditions.