• The Korean Journal of Zoology
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• v.3 no.2
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• pp.13-18
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• 1960

For the study on the sex ratio in natural populations of the different localities, the amphibian species were collected as the materials at the seven localities in Korea, and were obtained the following results. The sex ratios of each amphibian species suggest that each has it's own specific sex rations the following list. Rana nigromaculata H. : 109-39, Rana rugosa SCH. : 67.44, Rana temporaria coreana O. : 158.45, Hyla arborea japonica G. : 137.70. In Rana nigromaculata H. the average sex ratio was 109.39 as the above list, and its was reached statistically significant level according to the different localiies. The sex ratio was generally higher in the eastern area than that in the western area in this country. The sex ratio of the adult frogs of Rana nigromaculata H. was 135.18 , and it has a statistically significant level by each locality but the sex ratio of the younger frogs of the same species was 100.97 which was a little lower than that in the adult, and it was not laid at a significant level according to the localities. There is no doubt that the difference of sex ratios according to the localities was mainly due to the different ratios of the adult frogs which were effected on the constitution of sex by environmental factors in each locality.

• Proceedings of the Optical Society of Korea Conference
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• 2000.02a
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• pp.10-11
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• 2000

광통신을 이용한 근거리 전송과 장거리 전송에서 1.3 및 1.55 $mu extrm{m}$ 파장 영역의 빛이 사용되고 있다. 향후, 각 가정마다 광선로를 연결하는 Fiber-to-the-home (FTTH)의 개념과 광CATV가 발전함에 따라 1.3 및 1.55 $\mu\textrm{m}$ 빛을 검출하는 소자와 송신하는 소자가 필요하게 된다. 본 논문에서는 이러한 다중파장을 검출할 수 있는 집적소자를 제작 및 측정하였다. 본 논문에서 사용된 epitaxial layer의 구조는 N-InP 기판 위에 1 $\mu\textrm{m}$의 n-InP buffer층, 5층의InGaAs/InGaAsP 다중양자우물과 0.2 $\mu\textrm{m}$ InGaAsP separate confinement heterostructure (SCH) 층, 0.5$\mu\textrm{m}$ InP clad층과 0.1 $\mu\textrm{m}$ InGaAs cap 층으로 구성되어있다. 모든 epi 층은 InP 기판에 격자 정합이 되어있다. 다중양자우물구조는 84 $\AA$의 InGaAs 우물층과 100 $\AA$의 InGaAsP 장벽층으로 구성되며, 상온에서 0.787 eV (1.575 $\mu\textrm{m}$)의 bandgap energy를 갖도록 설계하였다. (중략)

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.7
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• pp.2246-2260
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• 2014

In this paper, a secure multilevel quadrature amplitude modulation (MQAM) scheme is proposed for the physical layer security (PLS) of the wireless communications. In the proposed scheme, each transmitted symbol's signal constellation (SC) is hopping with the control of two unique factors: amplitude distortion (AD) factor and phase hopping (PH) factor. With unknown the two factors, the eavesdropper cannot extract effective information from the received signal. We first introduce a security metric, referred to as secrecy gain, and drive a lower bound on the gain that the secrecy capacity can be improved. Then, we investigate the relationship among the secrecy gain, the signal to noise power ratios (SNRs) of the main and wiretap channels, and the secrecy capacity. Next, we analyze the security of the proposed scheme, and the results indicate that the secrecy capacity is improved by our scheme. Specifically, a positive secrecy capacity is always obtained, whether the quality of the main channel is better than that of the wiretap channel or not. Finally, the numerical results are provided to prove the analytical work, which further suggests the security of the proposed scheme.

• Journal of Photoscience
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• v.9 no.1
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• pp.17-22
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• 2002

Studies have been conducted to explore photoaddition reactions of N-methylthiophthalimide with $\alpha$-silyl-n-electron donors Et$_2$NCH$_2$SiMe$_3$, n-PrSCH$_2$SiMe$_3$ and EtOCH$_2$SiMe$_3$. Photoaddition of $\alpha$-silyl amine Et$_2$NCH$_2$SiMe$_3$ to N-methylthiophthalimide occurs in $CH_3$CN and benzene to produce non-silicon containing adduct in which thiophthalimide thione carbon is bonded to $\alpha$-carbon of $\alpha$-silyl amine in place of the trimethylsilyl group. In contrast, photoaddition of EtOCH$_2$SiMe$_3$ to N-methylthiophthalimide generates two diastereomeric adducts in which thiophthalimide thione carbon is connected to $\alpha$-carbon of $\alpha$-silyl ether in place of u-hydrogen. Based on a consideration of the oxidation potentials of u-silyl-n-electron donors and the nature of photoadducts, mechanism for these photoadditions involving single electron transfer(SET) -desilylation and H atom abstraction pathways are proposed.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.11 no.2
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• pp.61-66
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• 1989

Osteopetrosis (Albers-Schonberg disease) is a rare disease characterized by generaized sclerosis of bones, hepatoslenomegaly, pancytopenia, multiple fracture, blindness. The disease shows characteristic radiographic feature and two rather well-defined pattern have been recognized. We experienced a case of osteopetrosis in a 31 year old man, who has had pus discharge and fetid odor after extraction of upper maxillary molar. We made a brief review of literature.

• Biomolecules & Therapeutics
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• v.20 no.5
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• pp.487-491
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• 2012

The aim of this study was to investigate the inhibitory effects of rutaecarpine on DNA strand breaks and apoptosis induced by hydrogen peroxide ($H_2O_2$) in murine Hepa-1c1c7 cells. Oxidative DNA damage was estimated by nuclear condensation assessment, fluorescence-activated cell sorting analysis, and Comet assay. Rutaecarpine inhibited cell death induced by $500{\mu}M$ $H_2O_2$, as assessed by 4',6-diamidino-2-phenylindole (DAPI) staining. Treatment with rutaecarpine reduced the number of DNA strand breaks induced by $H_2O_2$, as assessed by DAPI staining and Comet assay, and increased quinone reductase, phosphatidylinositol 3-kinase, and pAkt protein levels, as assessed by western blotting.

• Journal of Information Management
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• v.29 no.2
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• pp.54-62
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• 1998

Catalogers have been reporting the ways they use the Internet for several years, but as yet there has been little evaluation done to determine for which areas of cataloging the Internet is a valuable tool and for which areas it is not as useful. A survey was conducted in an effort to elicit this information. The responses indicated four areas in which catalogers use the Internet : searching the OPACs of other libraries, communicating with colleagues, accessing online cataloging documentation and publications, and authority work. Some catalogers also related processes for which they have found the Internet to not be efficient.

• Elastomers and Composites
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• v.44 no.4
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• pp.366-372
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• 2009

The present study covers the optimal design for a lens module in a mobile phone camera by using the design of experiments (DOE) and finite element (FE) analysis. FE analyses are performed to investigate the effect of design parameters on the amount of torque required to assemble a barrel and a housing part. The DOE approach is then performed to optimize the design parameters in order to maintain an appropriate torque with less variations.

• Advances in pediatric surgery
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• v.6 no.1
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• pp.50-55
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• 2000

Pathologic lead points are found in a few intussusception patients. To evaluate the pathologic lead points in childhood intussusception, a retrospective review of 227 operated cases of intussusception treated at the Yeungnam University Hospital from January 1986 to April 1999. The patients were divided into 2 groups; idiopathic group 209 cases, (92.1 % and lead points group 18 cases, 7.9 %). Intussusception developed between age two months and six months in both groups. Enteroenteric type of intussusception was relatively more frequent in the lead point group than in idiopathic group. The lead points were veil (10 cases, 52.6 %), Meckel's diverticulum(3 cases, 15.8 %), lymphoma(3 cases, 15.8 %), ectopic pancreas(2 cases, 10.5 %), Henoch-Sch$\ddot{o}$nlein purpura(1 cases, 5.3 %). The bowel resection rate was 44.4 % in the lead point group and 8.6% in idiopathic group. The recurrence rate was 5.56 % in lead points group and 1.44 % in idiopathic group.

• Proceedings of the KIEE Conference
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• 2007.10a
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• pp.293-294
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• 2007

This paper addresses the adaptive controller for efficiency optimization of induction motors. The paper describes an adaptive controller based on-line efficiency optimization control of a drive that uses a direct vector controlled induction motors. To improve the efficiency of the induction motors, it is important to find the optimal flux reference that minimize power loss. The proposed optimal flux reference is derived using a power loss function that is constructed with stator resistance losses, rotor resistance losses and core losses. The proposed sliding mode flux observer generates estimates the unmeasured rotor fluxes. An optimal efficiency controller has goal of maximizing the efficiency for a given speed and load torque. A simulation shows the effectiveness of the proposed technique.