• Journal of Aquaculture
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• v.17 no.2
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• pp.128-132
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• 2004

Reproductive cycle of the brown sole, Limanda herzensteini was investigated by means of histological methods. The testis showed the presence of seminiferous tubule. The tubule consisted of many testicular cysts, each of which contained numerous germ cells - all at the same developmental stage. The ovary consisted of several ovarian lamellae and the oogonia originated from the inner surface of the ovarian lamella. Oocyte development was group-synchronous. Gonadosomatic index (GSI) of the male and female was the highest in January and March, respectively. Reproductive cycle could be classified into the growing (June-September), maturation (October-December), ripe and spent (January-March), and recovery and resting (April-May).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.3
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• pp.141-146
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• 2007

We investigated the reproductive cycle of the striped eel catfish Plotosus lineatus. Specimens were sampled in the coastal waters of Sungsan and Jocheon, east of Jeju, Korea, from September 2001 to August 2002. The gonadosomatic index (GSI) in females and males were reached a maximum in June $(14.18{\pm}10.38)$ and July $(0.35{\pm}0.12)$, respectively. Based on histological observations and GSI variation, the reproductive cycle was classified into the following successive stages: in females, growing (September-April), mature (April-June), spawning (June-July), and degenerative and recovery (July-September) and in males, growing (August-December), mature (September-May), spent (April-July), and degenerative and recovery (June-August). The total length at 100% maturity exceeded 15 cm and the fecundity ranged from 525 to 1176 eggs. The fecundity was correlated positively with total length and body weight. Histological observations of the gonads suggest that this species is a spring-summer spawner with group-synchronous type oocyte development.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.6
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• pp.554-558
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• 2000

Reproductive biology of the female red tongue sole, Cynoglossus joyneri was investigated by means of histological methods. Gonadosomatic index (GSI) was the highest in June. Developmental pattern of oocytes was group-synchronous. Egg stalk and yolk nucleus were observed in the early growing oocytes. Reproductive cycle could be classified into the growing ($February{\~}May$), maturation ($May{\~}June$), ripe and spent ($June{\~}August$), and recovery and resting ($August{\~}February$). The absolute fecundity per individual ($TL 28.1{\~}30.8 cm$) was 2,197 and relative fecundity per g body weight was 18.0.

• Journal of Korean Neurosurgical Society
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• v.46 no.4
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• pp.351-354
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• 2009

Objective : Combined hyperative dysfunction syndrome (HDS) defined as the combination of HDSs such as trigeminal neuralgia (TN). hemifacial spasm (HFS) and glossopharyngeal neuralgia (GPN), which mayor may not occur simultaneously on one or both sides. We reviewed patients with combined HDS and demonstrated their demographic characteristics by comparing them with those of patients with a single HDS. Methods : Between October 1994 and February 2006, we retrospectively studied a series of 1,720 patients who suffered from HDS and found 51 patients with combined HDSs. We analyzed several independent variables in order to evaluate the prevalence and etiologic factors of combined HDS. Results : The combined HDS group accounted for 51 of 1,720 (2.97%) patients with HDS; 27 cases of bilateral HFS, 10 cases of bilateral TN and 14 cases of HFS with TN. Their mean age was 52.1 years (range, 26-79 years). There were 5 men and 46 women. Seven patients had synchronous and 44 patients metachronous onset of HDSs. By comparison of combined and single HDS groups, we found that age and hypertension were closely associated with the prevalence of combined HDS (p<0.05). Conclusion : This study revealed that combined HDS was very rare. Hypertension and age might be the most important causative factors to evoke combined HDS.

• Environmental Analysis Health and Toxicology
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• v.19 no.1
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• pp.73-80
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• 2004

숭어의 생식주기를 밝히기 위해 2002년 2월부터 2003년 3월까지 제주도 동남부 연안에서 채집하였고, 난모세포의 발달과정을 조직학적 방법으로 관찰하였다. 난모세포의 발달과정은 GSI변화와 밀접하였다. GSI는 9월에 급격히 증가하여 12월에 최고 값을 나타내었다. 난소의 조직학적 관찰결과, 염색인기와 주변인기의 난모세포는 연중 관찰되었으며,8월에는 일부에서 난황을 포함하는 난모세포가 관찰되었다. 대부분의 난모세포가 10월과 12월에는 난황구기 단계의 난모세포로 발달했다. 10월과 12월에 난황구기 난모세포들을 가진 개체의 출현이 가장 높았으며, 잔존여포와 퇴화 난모세포는 2월부터 관찰되었다. 숭어의 주 산란기는 11월에서 1월이고, 난군동기발달형의 난소를 가지며 외양으로 이동하여 산란하는 어류에 속한다.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.4
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• pp.349-355
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• 2019

Reproductive ecology of rabbit fish, Siganus fuscescens were investigated from samples collected monthly in the coastal waters off Jeju Island of Korea from February to December 2014. In male and female of S. fuscescens, the values of GSI were reached high values between July to August in which the water temperature was high, and then decreased until December. The occurrence of individuals which have mature eggs in ovary were higher from July to August. Therefore, a main spawning season was estimated from July to August, with the highest peak in July. Throughout histological observation of the ovary in the spawning period, S. fuscescens belong to an group-synchronous and has a one spawning season a year. Fecundity of ovary ranged from 380,000 to 2,600,000 during the spawning period. Size at 50% sexual maturity, determined from logistic equation, were 25.1 cm TL which is over two years.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.385-388
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• 2001

In this paper, the gearless traction machine drive system using a permanent-maget motor for high-speed elevators is addressed. This application of permanent-magnet motor to the elevator traction machine enables several improvements including higher efficiency, better ride comfort, smaller size and weight, and so on. PWM boost converter is also adopted so that DC-link voltage regulation, hi-directional power flow, and controllable power factor with reduced input current harmonics are possible. To increase reliability and performance, the control board, which can include the car and group controller as well as PWM converter and inverter controller, is designed based on TMS320VC33 DSP The simulator system for high-speed elevators has been developed so that the drive system of high-speed elevator can be tested without my limitation on ride distance and the load condition. Some experimental results are given to verify the effectiveness of the developed system.

• Bulletin of the Korean Chemical Society
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• v.11 no.1
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• pp.49-54
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• 1990

The gas-phase thermolysis reactions of ${\alpha}$- and ${\beta}$-methylated ethyl formates, Y = $CH-X-CHR_1CH_2R_2$ where X = Y = O or S and $R_1\;=\;R_2$ = H or $CH_3$, are investigated theoretically using the AM1 method. The experimental reactivity order is reproduced correctly by AM1 in all cases. The thermolysis proceeds through a six-membered cyclic transition state conforming to a retro-ene reaction, which can be conveniently interpreted using the frontier orbital theory of three-species interactions. The methyl group substituted at $C_{\alpha}\;or\;C_{\beta}$ is shown to elevate the ${\pi}$-HOMO of the donor fragment (Y = C) and depress the ${\sigma}^{\ast}$-LUMO of the acceptor fragment ($C_{\beta}$-H), increasing the nucleophilicity of Y toward ${\beta}$-hydrogen which in turn increases the reactivity. The two bond breaking processes of the $C_{\alpha}$-X and $C_{\beta}$-H bonds are concerted but not synchronous so that the reaction takes place in two stages as Taylor suggested. The initial cleavage of $C_{\alpha}$-X is of little importance but the subsequent scission of $C_{\beta}$-H occurs in a rate determining stage.

• Development and Reproduction
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• v.25 no.3
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• pp.157-171
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• 2021

To determine whether the reproductive processes of sea bass, Lateolabrax japonicus, proceed normally after transportation from an outdoor net-cage into indoor tanks, we examined changes in the gonadosomatic index (GSI), histological gonadal tissue, and plasma levels of sex hormones (testosterone and estradiol-17ß) during their annual reproductive cycle. We also measured maturation and spawning across two sea water salinity levels (full and low salinity). Fecundity was estimated by the relationship between egg number and body size in female sea bass. Monthly changes in the GSI, histological gonadal tissues, and oocyte size showed both male and female sea bass reach final maturation in January and February, respectively, indicating that the spermiation of males occurs earlier than the spawning of females. The histological results indicated that the sea bass is a multiple spawner, similar to many marine teleosts, exhibiting group-synchronous oocyte development. Female maturation and spawning were enhanced in lower salinity seawater (29.6-31.0 psu) compared to that of normal salinity (34.5-35.1 psu). These results confirm that sea bass reproduction can occur successfully in captivity and imply that fertilized eggs can be collected from February to March. Additionally, our results show that lower salinity enhances oocyte maturation and spawning of female sea bass.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.11
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• pp.4372-4394
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• 2020

The distribution of popular videos incurs a large amount of traffic at the base stations (BS) of networks. Device-to-multi-device (D2MD) communication has emerged an efficient radio access technology for offloading BS traffic in recent years. However, traditional studies have focused on synchronous user requests whereas asynchronous user requests are more common. Hence, offloading BS traffic in case of asynchronous user requests while considering their time-varying characteristics and the quality of experience (QoE) of video request users (VRUs) is a pressing problem. This paper uses social stability (SS) and video loading duration (VLD)-tolerant property to group VRUs and seed users (SUs) to offload BS traffic. We define the average amount of data transmission (AADT) to measure the network's capacity for offloading BS traffic. Based on this, we formulate a time-varying bipartite graph matching optimization problem. We decouple the problem into two subproblems which can be solved separately in terms of time and space. Then, we propose the socially aware D2MD user selection (SA-D2MD-S) algorithm based on finite horizon optimal stopping theory, and propose the SA-D2MD user matching (SA-D2MD-M) algorithm to solve the two subproblems. The results of simulations show that our algorithms outperform prevalent algorithms.